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1

Николаевна, Агеева Галина, Агєєва Галина Миколаївна, Agieieva Galyna, Леонид Иванович Кривелев, Леонід Іванович Крівєльов та Leonid Krivjelov. "Маркетинговые исследования применения продукции Концерна "Стирол" в качестве утеплителя ограждающих конструкций зданий и теплоизоляции оснований аэродромных и дорожных покрытий". Thesis, Національний авіаційний університет, 2002. https://er.nau.edu.ua/handle/NAU/52478.

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Анотація:
1. Разработка конструктивно-технологической и нормативно-методологической документации по использованию утеплителей Концерна "СТИРОЛ": Отчет о НИР (промежут.) / Рук. НИР Л. И. Кривелев / Гос.науч.-исслед. и проектно-изыскат. ин-т "НИИпроеконструкция"; №ДР 0101U 007707. № ДО 0302U001154. - К., 2001. - 114 с. 2. СНиП 11-3-79*. Строительная теплотехника // Минстрой России. 1995. 3. Опыт института "НИИПРОЕКТРЕКОНСТРУКЦИЯ" в проектирования реконструкции пятиэтажных жилых зданий первых массовых серий/ Гос.науч.-исслед. и проектно-изыскат. ин-т "НИИпроектреконструкция". - К.. 1999. - 43 с.
Приведены результаты маркетинговых исследований, выполненных с целью совершенствования технической и рыночной политики Горловского Концерна "СТИРОЛ" в производстве утеплителя пенополистирол. Разработаны рекомендации по изменению качеств и технологии выпускаемой продукции.
Концентр "Стирол"
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Даценко, Ольга Олександрівна. "Підвищення енергоефективності дитячого садочку та моделювання енергоспоживання з використанням сучасного програмного забезпечення". Master's thesis, КПІ ім. Ігоря Сікорського, 2020. https://ela.kpi.ua/handle/123456789/39531.

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Анотація:
Магістерська дисертація «Підвищення енергоефективності дитячого садочку та моделювання енергоспоживання з використанням сучасного програмного забезпечення» складається з 99 сторінок, 28 рисунків, 49 таблиць, а також містить 42 джерел в переліку посилань. Актуальність теми полягає у використанні сучасних методів моніторингу споживання енергоресурсів для прийняття найбільш ефективних управлінських рішень з точки зору енергоефективності. Метою роботи є дослідження енергоспоживання будівлі на прикладі дитячого садка та впровадження заходів з енергозбереження. Завдання дослідження – провести енергоаудит дитячого садку, розрахувати навантаження на систему опалення та електропостачання, визначити шляхи підвищення енергоефективності будівлі та провести розрахунок доцільності проведення заходів з енергозбереження, розробити систему автоматизованого обліку енергоносіїв. Об'єкт дослідження – дитячий садочок у м. Києві серійних часів забудови. В ході роботи виконано детальне енергетичне обстеження, що включало: - збір вихідних даних щодо характеристик будівлі, її огороджувальних конструкцій та внутрішньобудинкових інженерних систем; - збір даних щодо енергоспоживання об’єкту; - вивчення режимів експлуатації; - уточнення геометричних характеристик будівлі; - розрахунки теплотехнічних показників огороджень, - дослідження умов мікроклімату будівель, - виконання необхідних інструментальних вимірювань і розрахунків; - визначення питомих енергетичних характеристик; - розробка економічно обґрунтованих заходів з енергозберження з доведенням характеристик огороджень до нормативних вимог; - моделювання енергоспоживання будівлі в спеціалізованому програмному продукті з визначенням енергетичних характеристик; - розробка пропозицій щодо розвитку системи енергетичного менеджменту. Предмет дослідження – аналіз доцільності проведення заходів з енергозбереження в сферах тепло- та електропостачання в дитячому садку в місті Київ з використанням сучасного програмного забезпечення. Наукова новизна магістерської дисертації полягає у розробці системи автоматизованого обліку енергоносіїв у дитячому садку. Отримані результати, запропоновані методики та підходи можуть використовуватись для аналізу енергоспоживання інших будівель.
The master's dissertation "Improving the energy efficiency of kindergarten and modeling energy consumption using modern software" consists of 99 pages, 28 figures, 49 tables, and also contains 42 sources in the list of references. The relevance of the topic is to use modern methods of monitoring the consumption of energy resources to make the most effective management decisions in terms of energy efficiency. The purpose of the work is to study the energy consumption of the building on the example of a kindergarten and the implementation of energy saving measures. The task of the research is to conduct an energy audit of the kindergarten, calculate the load on the heating and electricity supply system, determine ways to increase the energy efficiency of the building and calculate the feasibility of energy saving measures, develop an automated energy metering system. The object of research is a kindergarten in Kyiv of serial times of construction. In the course of the work a detailed energy audit was performed, which included: - collection of initial data on the characteristics of the building, its enclosing structures and indoor engineering systems; - collection of data on energy consumption of the facility; - study of operating modes; - specification of geometrical characteristics of the building; - calculations of thermal indicators of protections, - study of the microclimate of buildings, - performance of necessary instrumental measurements and calculations; - determination of specific energy characteristics; - development of economically justified measures for energy saving with bringing the characteristics of fences to regulatory requirements; - modeling of energy consumption of the building in a specialized software product with the definition of energy characteristics; - development of proposals for the development of the energy management system. The subject of the research is the analysis of the expediency of carrying out energy saving measures in the spheres of heat and electricity supply in a kindergarten in the city of Kyiv with the use of modern software. The scientific novelty of the master's dissertation is to develop a system of automated energy accounting in kindergarten. The obtained results, proposed methods and approaches can be used to analyze the energy consumption of other buildings.
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Зіменко, Сергій Вікторович. "Моделювання теплових втрат через огороджувальні конструкції складної форми". Master's thesis, Київ, 2018. https://ela.kpi.ua/handle/123456789/24683.

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Анотація:
Обсяг магістерської роботи 113 – аркушів, кількість рисунків – 51, таблиць – 48, додатків – 2. Мета магістерської дисертації – оцінка теплозахисних властивостей огороджувальних конструкцій житлових будівель з урахуванням теплопровідних включень. Під час виконання магістерської дисертації було розглянуто наявні програмні та приладові інструменти, методики оцінки на прикладі об’єкту житлового фонду, підходи до зниження рівня теплопередачі огороджувальних конструкцій, економічний ефект від впровадження енергоефективних проектів з врахуванням результатів моделювання та його вплив на загальний енергетичний баланс будівлі. На основі розділу аналізу програмного забезпечення складено передумови та визначено потребу у впровадженні стартап проекту, для якого визначено потенційну стратегію виходу на ринок. Результати даної дисертації активно впроваджувалися у практичний процес енергетичного обстеження та можуть бути використані у сферах інжинірингу та проектування.
The volume master's thesis equals 113 pages, quantity of figures – 51, tables – 48, applications – 2. The purpose of the master's dissertation is the assessment of the heat-protective properties of the enclosing structures of residential buildings of non-standard constructions. During the implementation of the master's thesis, existing software and instrumental tools, valuation techniques on an example of a housing stock, approaches to reducing the level of heat transfer of fencing structures, the economic effect of implementing energy efficient projects taking into account the results of modeling and their impact on the overall energy balance of the building were considered. Based on the software analysis section, the preconditions have been created and the need for implementation of the project startup has been determined, for which a potential market entry strategy has been identified. The results of this dissertation have been actively implemented in the practical process of energy survey and can be used in the fields of engineering and design.
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Лукашенко, Євгеній Олексійович. "Енергоефективність системи «Джерело теплоти – людина – огороджувальні конструкції» на прикладі житлової будівлі". Master's thesis, КПІ ім. Ігоря Сікорського, 2021. https://ela.kpi.ua/handle/123456789/46529.

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Анотація:
Обсяг магістерської роботи – 92 аркушів, кількість рисунків – 32, таблиць – 34 . Актуальність теми дослідження пов’язана з постійним підвищенням тарифів на комунальні послуги, заохоченням людей до заощадження, а отже, потребою в нових способах зниження енергоспоживання. Основними засобами зниження енергоспоживання є більш раціональне та ефективне використання ресурсів та термомодернізація. Житловий фонд в Україні є однією з найбільш енергоємних галузей, тому зрозуміло, що впровадженню заходів у цій сфері слід віддавати пріоритет. Мета дослідження – визначення показників енергоефективнсті та рівня теплового комфорту гуртожитку. Об’єкт дослідження – 10-поверхова житлова будівля за адресою вул. Борщагівська, 173/187 , м. Київ. Предмет дослідження – енергоспоживання будівлі, теплотехнічні характеристики огороджувальних конструкцій будівлі, характеристики інженерних мереж. Наукова новизна досягнутих результатів полягає у розробці методичних аспектів і методів аналізу, оцінки та моніторингу показників енергоефективності житлових будинків. Розроблено моделювання з 3D-візуалізацією та детальним аналізом для розрахунку фотоелектричних систем у поєднанні з електроприладами, акумуляторними системами. Матеріали магістерської дисертації можуть бути використані при підготовці і викладанні дисциплін «Енергозбереження будівель і споруд» та «Методи енергомоніторингу та енергоаудиту будівель» для студентів спеціальності 141 «Електроенергетика, електротехніка та електромеханіка», 144 «Теплоенергетика». Тематика досліджень, проведених у магістерській дисертації, представляє практичний інтерес і рекомендується ПрАТ «Вімм-Білль-Данн Україна» до впровадження на реальному об’єкті – житловій 10-поверховій будівлі за адресою вул. Борщагівська, 173/187 , м. Київ. Апробація результатів дослідження:: Основні результати за тематикою роботи обговорювалися та доповідалися на науково- технічних конференціях. Опубліковані тези: 1. IІ науково-технічна конференція магістрантів ІЕЕ (17 листопада 2021 р.).
The volume of master's work - 92 sheets, the number of drawings - 32, tables - 34. The relevance of the research topic is related to the constant increase in utility tariffs, encouraging people to save, and hence the need for new ways to reduce energy consumption. The main means of reducing energy consumption are more rational and efficient use of resources and thermal modernization. Housing in Ukraine is one of the most energy-intensive industries, so it is clear that the implementation of measures in this area should be given priority.The purpose of the study is to determine the indicators of energy efficiency and the level of thermal comfort of the dormitory. The object of study - a 10-storey residential building at vul. Borshchahivska, 173/187, Kyiv. The subject of research - energy consumption of the building, thermal characteristics of the enclosing structures of the building, the characteristics of engineering networks. The scientific novelty of the achieved results is the development of methodological aspects and methods of analysis, evaluation and monitoring of energy efficiency indicators of residential buildings. A model of dynamic modeling with 3D-visualization and detailed shading analysis for the calculation of photovoltaic systems in combination with electrical appliances, battery systems has been developed. Materials of the master's dissertation can be used at preparation and teaching of disciplines "Energy saving of buildings and constructions" and "Methods of energy monitoring and energy audit of buildings" for students of a specialty 141 "Electric power, electrical engineering and electromechanics", 144 "Heat energy". The subject of research conducted in the master's dissertation is of practical interest and is recommended by LLC "ESCO Ukraine" for implementation on real objects - a 10-storey residential building at vul. Borshchahivska, 173/187, Kyiv. Approbation of research results: The main results on the topic of the work were discussed and reported at scientific and technical conferences. Published theses: 1. II scientific and technical conference of IEE undergraduates (November 17, 2021).
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Shahrestani, Mehdi. "Multiple attribute decision making for HVAC&R systems selection." Thesis, University of Reading, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.603550.

Повний текст джерела
Анотація:
Buildings account for 40% of total energy consumption in the UK and more than 55% of this energy is used by heating, ventilation, air-conditioning and refrigeration (HVAC&R) systems. This significant energy demand and the ascending trend in utilising HVAC&R systems together with the global need to impose energy-efficiency measures underline the importance of selecting the most appropriate HVAC&R system in a design process. In the early stages of the design and construction of a building, the design engineer is responsible for considering various systems in the process of HVAC&R systems selection. Although a broad range of simulation tools is developed for performance evaluation of HVAC&R systems, none of them is capable of performing a decision making process for HVAC&R systems selection. Therefore, the contribution of this study to knowledge has been the development of a multiple attribute decision making tool for HVAC&R systems selection for office buildings in the UK. Firstly, a set of reference office buildings was developed as representative of the UK office building stock and one of them was selected for further study. Then, a set of common alternative HVAC&R systems was identified. The reference office building, assumed to be located in London, together with the alternative HVAC&R systems were simulated in the TRNSVS and their technical performance, economic aspects and environmental impacts were assessed. Finally, to choose the most appropriate system among the alternatives a fuzzy multiple attribute decision making method was used to formulate the process of decision making. The scope of this study was further extended by considering 18 climate regions in the UK together with the effect of climate change in the decision making process using the degree-days theory. In addition, the UK Government's electricity decarbonisation plans were integrated to the developed decision making model. Finally, the model was transferred into a computational tool with a user-friendly interface developed in Matlab.
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Ealiwa, Mansour Ali. "Designing for thermal comfort in a naturally ventilated and air conditioned buildings in summer season of Ghadames, Libya." Thesis, De Montfort University, 2000. http://hdl.handle.net/2086/4758.

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Анотація:
The outdoor climate of an area has a significant impact on housing and urban fabric as a whole, and the more extreme a climate, the more necessary it becomes to respond to it. Thus the climate should be regarded as a significant modifier of the built environment; thermal discomfort within building environments is a prevalent and significant issue throughout the developed and developing countries. There is considerable disagreement in the research community concerning whether comfort standards developed in the climate of North America and Europe are appropriate for use in other countries with more extreme climatic conditions. This research focuses on designing for the conditions of thermal comfort in hot dry climate regions. The research reports field surveys in both naturally ventilated (NV) buildings and air-conditioned (AC) buildings in summer season, with reference to Ghadames in Libya. This involves objective measurements and subjective questionnaire study with a view to testing the validity of the established thermal comfort models: Fanger's PMV model and the Adaptive model. It reviews the results from the field survey within those two types of buildings in the summer seasons of 1997 and 1998, which experiences the hot-dry climate of North Africa. It shows how the residents responded to the environmental conditions, social needs, and architectural character such as building design and thermal mass. The method of study and analysis are critically described. The subjective data was collected and tabulated by using questionnaires, which have been widely used and shown to be effective, to determine people's votes through scales modified especially for this purpose. Questionnaires were collected from households of 60 buildings: 30 old NV buildings and 30 new AC buildings involving a total of 270 participants from both types of buildings. The questionnaires compare the significance of the thermal sensation, the thermal comfort, and the preference scales of each type of building. The objective survey consisted of 19 observations of empirical data (in the 9 old NV buildings, and in the 10 AC new buildings) to validate the performance of the current thermal comfort indices. The results show that the PMV model is not valid, unless modified, for predicting the thermal comfort in old buildings, in Ghadames oasis, Libya. Thus a modification is proposed. However, the results from modem air-conditioned buildings have shown that there is good agreement between Fanger's model and the actual mean vote (AMV) values reported by the occupants in these buildings. The results from the present study show also that the neutral temperatures in old and new buildings are 31.6°C and 29.4°C respectively. The adaptive model, which is developed by Auliciems (1983), is shown to be valid, without modification, for predicting the thermal comfort of sedentary occupants in such environments. The results indicate that the construction of residential dwellings using traditional methods is more conducive to the climatic conditions of hot-dry climates and suitable for the cultural requirements and life style of the occupants. Human thermal comfort was assessed using the adaptive model, to show that the climate and personal behaviour have a significant impact on human comfort perception and building design.
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Lam, Hoi Yan. "Thermal performance of deciduous climbing plants on glazed building façades." Thesis, University of Brighton, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.439205.

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8

Carey, P. S. "Direct wind tunnel modelling of natural ventilation for design purposes." Thesis, University of Nottingham, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.422325.

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9

Ji, Yingchun. "Computational fluid dynamics modelling of displacement natural ventilation." Thesis, De Montfort University, 2005. http://hdl.handle.net/2086/4951.

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Анотація:
Natural ventilation is widely recognised as contributing towards low-energy building design. The requirement to reduce energy usage in new buildings has rejuvenated interest in natural ventilation. This thesis deals with computer modelling of natural displacement ventilation driven either by buoyancy or buoyancy combined with wind forces. Two benchmarks have been developed using computational fluid dynamics (CFD) in order to evaluate the accuracy with which CFD is able to model natural displacement ventilation flow. The first benchmark considers the natural ventilation of a single ventilated space with high and low level openings connected to the exterior driven by combined forces of wind and buoyancy. The second benchmark considers natural ventilation flow in a single space connected to an atrium driven by pure buoyancy. Simulation results of key ventilation parameters (stratification depth, temperature gradient and ventilation flow rate) have been compared with analytical and experimental models and close agreements have been achieved. The two benchmarks are defined using the RNG k-epsilon turbulence model. A pressure boundary is applied onto the ventilation openings directly and a porous medium boundary is used to assist the development of the thermal plume. This method has proved to be robust and the close agreement between the three modelling techniques indicates that CFD is able to model natural ventilation flows in simple geometries with acceptable accuracy and reliability. Using the benchmarks the influences of key CFD modelling parameters and building design issues have been investigated. For example, representing openings, heat source representation, stack height, and air inlet strategies. Natural displacement ventilation of a multi-storey building comprising an atrium is also addressed. Simple analytical models have been developed to describe the key air flow features within the ventilation system.
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Gough, Hannah. "Effects of meteorological conditions on building natural ventilation in idealised urban settings." Thesis, University of Reading, 2017. http://centaur.reading.ac.uk/71951/.

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Анотація:
With 50 % of the worlds population dwelling in urban environments and over 70 % of people’s time is spent indoors (at home, work or in vehicles). It is important to understand how the urban area effects the internal-external air exchange for buildings and how this may impact on the occupants, though this will differ depending on location. The urban area is complex, requiring multidisciplinary expertise in order to understand the driving features. Urban areas may be simplified down for study to reduce some of the complexity. The study undertaken at Silsoe, UK, used a full-scale staggered array of nine 6 m3 cubes to gain an understanding of the effects of meteorological variables on the natural ventilation rate and pressure coefficient. After 6 months 8 cubes were removed, leaving the instrumented cube isolated for 2 months. All equipment logged constantly, creating a dataset which covers a wide range of wind directions, wind speeds, temperature differences and atmospheric stabilities making the dataset unique from previous work. Changes in wind direction cause changes in the pressure coefficient for both isolated and array cases. However defining wind direction is difficult for the array due to the complex interaction of obstacle wakes. The relation between reference and local wind directions is non-linear. The flow within the array was dominated by mechanical turbulence generated by the wakes of the array elements, with the local turbulence intensity being 7 to 10 times greater than for an isolated cube. The presence of an opening had no effect on the pressure coefficient when acting as an inlet. Stability was found to have no effect due to the building being low-rise and the effects of turbulence could not be discerned from 30 minute averages for both pressure coefficient and ventilation measurements. The full-scale data were compared to a wind tunnel model of the site. This allowed for increased array sizes to be used. It was found that the length and size of the rows have a non-linear effect on the pressure coefficient of a cube within the array, with a limited array reducing the pressure coefficient by 10 to 50 % ± 5 % depending on measurement location. Pre-existing models predict the pressure coefficient for an isolated cube well, but do not accurately predict the pressure coefficient for a limited array due to the lack of wind direction and shielding terms. This is also true for the full-scale data. The three methods used to predict ventilation rate (tracer gas decay, pressure difference and the volumetric method) were all affected by different variables such as the presence of thermally driven ventilation, wind direction, location of the wind speed measurement and amount of turbulence within the flow. The difference in the volumetric flow methods depended on the wind speed measurement used, highlighting the difficulty in gaining an accurate representation of ventilation rate using wind speed alone, especially in an urban area. All three methods show more agreement for the array cases than for the isolated cube cases. Pre-existing empirical models of urban wind speed (CIBSE), pressure coefficient (ASHRAE and AIVC) and ventilation rate do not capture the dual behaviour of the ratio of local and reference wind speeds found for the array. This dual behaviour is demonstrated for 1, 5, 10, 30 and 60 minute averaging periods. This behaviour is not correlated to changes in wind direction, the turbulence or speed of the oncoming flow or internal-external temperature differences. A combination of frontal area density, sheltering factor, wind speed, wind direction, opening location and temperature differences within a ventilation model is required to accurately predict ventilation rate.
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11

Todd, Stephen P. "Water bath modelling of transient and time dependent natural ventilation flows." Thesis, Loughborough University, 2016. https://dspace.lboro.ac.uk/2134/23245.

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Since electricity was first harnessed, humanity has developed a lifestyle which can not exist without it. Traditionally, electricity has been created by burning fossil fuels which produces waste gases including carbon dioxide. These waste gases have accumulated in our atmosphere and are theorised to have contributed to a warming of the earth, causing a 0.4°C rise in average surface temperature since the 1970's (DECC 2013). A warming of the earth is thought to lead to increased frequency of catastrophic weather events such as droughts and heat waves, leading to many deaths (Met Office 2015). In recent years, there has been a drive to reduce our dependence on the burning of fossil fuels by making technologies more efficient, developing methods of electricity generation which do not involve the burning of fossil fuels as well as replacing techniques requiring high energy demands with low energy techniques. Natural ventilation is one such low energy technique which can replace more electricity intensive strategies such as mechanical ventilation and air conditioning whilst still ensuring a room which is neither too cold nor too warm and removes pollutants.
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12

Sykes, Joshua S. "Control of naturally ventilated buildings : a model predictive control approach." Thesis, University of Sheffield, 2017. http://etheses.whiterose.ac.uk/16487/.

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During operation, buildings consume a large amount of energy, around 40\% of global final energy use. A major challenge is to reduce the amount of energy used while still providing a comfortable environment for building occupants. The use of passive techniques, such as natural ventilation, is promoted in certain climates to provide low energy cooling and ventilation. However, controlling natural ventilation in an effective manner to maintain occupant comfort can be a difficult task, particularly during warm periods. One area which has been identified as having the potential for reducing energy consumption while maintaining occupant comfort is the use of more advanced control techniques. A technique which has been much explored in recent years for application in mechanically ventilated buildings is Model Predictive Control (MPC). MPC is a control technique which uses a model of the system dynamics and by solving an optimisation problem is able to determine the optimal control inputs. In this thesis the application of MPC to naturally-ventilated buildings is investigated. The essential component of an MPC strategy is the predictive model of the building's thermal dynamics. An empirical approach to modelling was taken using multilayer perceptron (MLP) neural network models. To use empirical data from a building to create a predictive model it is essential to ensure the quality of the data is appropriate. In order to assess the data available from buildings during normal operation four studies were carried out in different buildings. The data collected from these studies represent a range of natural ventilation scenarios and building types in different locations in the UK. To test the impact of identification procedures upon the resulting neural network models, an identification experiment was carried out using dynamic thermal simulation. Neural network models were trained using both the data from real buildings and the simulation data. Results showed that neural network models trained using data from real buildings were capable of good predictions. However, the lack of input excitation during normal operation resulted in models which did not capture the effect of the window opening control. The identification experiment demonstrated that by exciting the control input the resulting neural network models captured the effect of the control, making them suitable for MPC. The main focus of this thesis is the investigation of techniques to develop predictive models which can be utilised as part of an MPC strategy. However, to demonstrate the potential benefits of MPC a controller designed to maintain a suitable internal temperature is demonstrated. The controller utilised the neural network models developed using the data from the system identification experiment and a non-linear optimiser. The MPC method showed the potential to reduce overheating and improve upon the typical control used in the majority of buildings. Findings in this thesis demonstrate that empirical models capable of good predictions can be trained and could be successfully applied to the control of natural ventilation systems. Furthermore, the potential advantages of adopting an MPC approach to natural ventilation control are shown.
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13

Nigi, Hasn. "Air-conditioning systems monitoring for maintenance optimization." Thesis, University of Manchester, 2010. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.515169.

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14

Spentzou, Eftychia. "Refurbishment of apartment buildings in the Mediterranean Region for natural ventilation : implications for building design." Thesis, Loughborough University, 2015. https://dspace.lboro.ac.uk/2134/18592.

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With the emergence of climate change, the increasing figure of energy consumption for cooling in buildings expresses an urgent need for energy conscious design of new and existing buildings, and there is a significant opportunity for implementation of natural ventilation strategies. The high-energy consumption of the Greek domestic sector, the number of existing multi-storey apartment buildings, the small rate of building retrofitting in Greece and the warm, dry climate of Greece, indicate the potential to achieve significant energy reductions for cooling via natural ventilation. The aim of this research was to evaluate the energy saving potential of natural ventilation solutions for domestic buildings in the Mediterranean climate to deliver summer comfort, and to propose a low-energy refurbishment design guide. The natural ventilation efficiency of an urban multi-storey apartment building in Athens and the potential implementation of advanced natural ventilation strategies, were evaluated using modelling tools. This would provide the knowledge for future energy refurbishments. The building was a representative example of over 4 million buildings in Greece. Several ventilation strategies were implemented in a single apartment (51.4m2) and evaluated in order to enhance the existing single-sided ventilation strategy of the building, including: daytime and nighttime ventilation; cross ventilation strategies; use of a wind-catcher; lightweight dynamic façade with shading system; new internal openings; and passive downdraught evaporative cooling strategies. The ventilation performance of the strategies was investigated over the full cooling period using DTM simulations. Controlled natural ventilation strategies, in response to internal and external air properties, delivered: occupants comfort; ventilation rates increase; and reductions in air temperatures and in CO2 levels. Natural day and night ventilation contributed to significant temperature reductions (up to 7°C) relative to the base-case ventilation strategy. The proposed strategies marginally reduced the hours during the cooling period for which the CO2 levels exceeded the upper acceptable limit for comfort. The strategies also achieved air change rates above the minimum acceptable values for comfort were provided; and therefore occupants comfort was achieved. De-coupled internal-external steady state CFD airflow simulations were performed to predict wind pressures across the building openings, and to predict detailed ventilation rates for a number of climate scenarios. Using CFD it was possible to overcome the limitation of DTM and predict average pressures at the location of the openings, considering the location of the building within its surroundings (both external and internal flow simulations were performed), leading to accurate results. It was predicted that the ventilation performance of the wind catcher was significant relative to the simple single or cross-ventilation strategies. The downdraft evaporative cooling performed best at low ventilation rates providing up to 4°C further temperature reductions. Indoor comfort was provided during windless hours for specific strategies (buoyancy driven); this is significant considering that low wind speeds (below 1m/s) were predicted for 14% of the cooling period. The performance of the strategies varies considerably with regard to both wind speed and direction; these should be considered when retrofitting natural ventilation strategies in existing buildings. The proposed strategies delivered natural cooling and adequate ventilation rates, relative the base-case strategy. The combined wind catcher and dynamic façade strategy performed the best; this combined strategy would be recommended for the Mediterranean sub-climate, and for buildings comparable to the type studied. This should be combined with evaporative cooling strategies particularly during windless hours, and mechanical cooling only when these strategies do not provide sufficient performance. For both the CFD and DTM results, empirical relationships were established with statistical methods between indoor air properties and climate characteristics, which can be used to predict behaviours under conditions that have not been examined using simulations. This assists extrapolation of patterns in ventilation performance, to facilitate design guidance of the natural ventilation strategies for implementation in similar buildings. The established performance of the natural ventilation strategies in the case study building assisted the development of a prototype scenario for similar building designs with comparable climatic context. A low-energy refurbishment design guide for natural ventilation was proposed that provides guidelines and design recommendations. Retrofitting such natural ventilation strategies in existing apartment buildings in similar climates presents a significant opportunity to achieve significant energy consumption reductions.
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15

Mohammed, Mohammed Alhaji. "Natural ventilation : an evaluation of strategies for improving indoor air quality in hospitals located in semi-arid climates." Thesis, University of Newcastle upon Tyne, 2015. http://hdl.handle.net/10443/2837.

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This thesis is an investigation into improving natural ventilation in low rise hospital wards in Northern Nigeria. The climate of this region is semi-arid, during the dry season, sub-Saharan fine dust (Harmattan dust) is blown into the region from the North East and during the wet season, Mosquitos are prevalent. The energy infrastructure in the whole of Nigeria is under resourced; hence ventilation strategies’ based on mechanical extraction are not possible. Five wards within low rise hospital buildings were studied; these were purpose designed hospital buildings, not converted buildings. Questionnaire surveys of health care workers in the hospitals was conducted and revealed dissatisfaction with the buildings’ ventilation and Indoor Air Quality. The questionnaires were then followed up by Tracer Gas measurements and during the period of measurement there was only one occasion when a ward achieved an air change rate of 6-ach-1, the ASHREA Standard requirement for hospital buildings. To investigate methods of improving natural ventilation in these wards, a CFD model was developed of a representative ward, the model was validated against the Tracer Gas measurements; with an acceptable agreement of ≤ 15%. Using the CFD model, achievable ventilation strategies within the context of the location, were investigated, and a combination of cross ventilation utilizing windows on the windward and leeward sides of the ward together with a roof ventilator on the leeward side proved the most successful. All openings were screened to prevent the entry of mosquitos. This best case was further investigated with the wind direction at an oblique angle to the ward side. The oblique angle of wind attack reduced the air change rates but improved air circulation/mixing within the ward. With the exception when the wind direction was parallel to the ward side. To reduce the ingress of Harmattan Dust, was problematic given the energy restrictions, a low energy solution of introducing screened plenums on both the windward and leeward sides of the building proved successful. Larger dust particles were detained within the windward plenum and the smaller dust particles were exhausted into the leeward plenum. With the mosquito screens located on the large surface area of the plenum, the window screens were removed resulting in higher air change rates. Thus, it is recommended that, openings should be provided on the windward and leeward walls and on the roof toward the leeward side for efficient ventilation and airflow circulation at the occupancy level. The longer sides of the wards should be oriented toward the North-South to capture the North-East trade winds and South-West monsoon winds with oblique angle of attack. Plenums should be incorporated to the windward and leeward facades and Insect screen should be installed on the plenums instead of the wards’ openings to increase ventilation rates while excluding mosquitoes and decreasing dust particle concentration in the hospital wards. Openings should be at the middle of the windward and leeward walls and on the roof toward the leeward to avoid airflow short-circuiting. It is recommended to use insect screen with the porosity of 0.2 and when the outdoor local wind speed is ≤ 1.26 m/s (2 m/s: airport value), the ventilation should be supplemented with fan.
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16

Stewart, Gerald William. "Development of intelligent control strategies for the control of air temperature and airflow for dynamic processes operating within air conditioned environments." Thesis, Glasgow Caledonian University, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.688261.

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17

Acred, Andrew. "Natural ventilation in multi-storey buildings : a preliminary design approach." Thesis, Imperial College London, 2014. http://hdl.handle.net/10044/1/34322.

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Natural ventilation is a low-energy design strategy that has the potential both to significantly reduce energy usage in buildings and to provide a healthy and comfortable indoor environment. It has particular potential for use in tall, multi-storey buildings. However, the integration of natural ventilation into these large building designs has seen mixed success. Furthermore, there is a gap between simple 'rule-of-thumb' design guidance and detailed, computational design tools. This research attempts to bridge the gap between the simple and detailed with the broad aim of providing rapid and intuitive guidance for use in preliminary design. We use a simple mathematical approach to develop a coherent and easy-to-use framework for modelling ventilating flows, which quantifies the interactions between a core set of design variables. We focus in particular on buoyancy-driven ventilation in buildings with atria, ventilation stacks and/or similar vertical spaces that span multiple floors. Simple methods centred around hand calculations and design charts are developed to inform the sizing of vents in an 'ideal design' scenario, in which the desired ventilation flow rates and air temperatures are delivered to all occupants within a building. We define a measure of the ventilation performance of an atrium and use this to provide an indication of when an atrium is beneficial to a ventilation system design and when it is detrimental. We also use a transient flow analysis to consider 'off-design' scenarios, in which undesirable flow regimes may occur, and to place design tolerances on the building envelope. It is hoped that this work will form a point of reference for further research and for future revisions of design guidance literature.
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18

Lynch, Paul Michael. "Aspects of the fluid mechanics of night-purging multi-storey atrium buildings." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/39134.

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This research concerns the mathematical and physical modelling of the buoyancy-driven flow of warm air at night from a multi-storey atrium building by displacement ventilation. The process of clearing warm air from a building at night is known as 'night-purging'. The primary aim of this research was to enhance understanding of these flows to thereby facilitate efficient design of passively night-purged buildings. The thesis begins with a review of research on natural ventilation and night-purging. Particular focus is given to the conditions for achieving classical displacement flow, in which there is an absence of mixing between warm and cool air, as this has been shown to be the most efficient means of removing warm air from a space. We identify that the dynamics of the plumes of warm air discharged from the storeys into the atrium play a crucial role in the development of the thermal stratification in the atrium. The majority of research on turbulent plumes has concerned plumes from horizontal sources, while ventilation openings are often oriented at some angle off-horizontal. We therefore investigate how varying the angle of orientation of the plume source (or ventilation opening) affects the dynamics of the plume to determine the implications for buildings ventilated via wall-mounted windows. This modelling reveals that, for a significant proportion of a typical night-purge in a single storey, a plume from a vertically oriented opening will not project away from the opening. Thus the simple plume model we have developed will not apply during the late stages of a night-purge. In order to develop a model of plumes which do not project away from the source, we investigate the limiting case of a plume from a vertically distributed source (such as a vent) with zero source momentum flux, such that the motion is entirely parallel to the source. To investigate the overall flow in the building, guided by the results of the plume modelling, we develop a simplified mathematical model to predict the purging of warm air in a generic two-storey atrium building. The pre-dictions of the model enable the classification of night-purging behaviours into three distinct classes of flow, based on the chronology of a number of key events in the progression of a night-purge. Interrogation of the predictions suggests that two transitional behaviours which fall between the three classes of flow provide 'optimal' purging behaviour: one for purging just the storeys in a minimum time and the other for purging the entire building in a minimum time. Adaptation of the mathematical model facilitates the development of design curves for building designers to appropriately size ventilation openings in order to achieve the optimal night-purges. Complementary physical modelling in water-filled visualisation tanks enabled testing of the mathematical model predictions and optimal nightpurging behaviours. Whilst demonstrating the suitability of a simplified mathematical approach to predicting what are complex patterns of airflow, the physical modelling highlighted the complexity of the developing stratification in the atrium and raises a number of new questions for future research.
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19

Alrazni, W. "Improving Indoor Air Quality (IAQ) in Kuwaiti housing developments at design, construction, and occupancy stages." Thesis, University of Salford, 2016. http://usir.salford.ac.uk/39210/.

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There are many sources of outdoor pollution in Kuwait which then makes natural ventilation a poor mechanism for good Indoor Air Quality (IAQ). Therefore, a mechanical or hybrid ventilation system is necessary. First of all, Kuwait is situated in the northeast of the Arabian Peninsula in Western Asia with a desert weather climate. The prevailing wind is north and northeast and that causes sand storms. Also most of the towns and cities are situated and constructed within the vicinity of many industrial sites, petroleum downstream/upstream facilities (including Kuwait's three refineries, petrochemical complexes, crude oil production points etcetera) and many small industries. Most housing construction projects, as well as schools, commercial and governmental buildings are built in the downwind of the polluted air emitted from such plants, therefore, there is the potential for consequential health effects related to the ambient air. As a result, there is a prevalence of asthma and rhinitis among the schoolchildren in Kuwait. The estimated prevalence of asthma among school children was 22.4% and that of rhinitis was 23% (Abal et al., 2010). It was evident from a preliminary study that indoor air quality (IAQ) in Kuwait housing is under-researched and there is a clear lack of awareness amongst building stakeholders (Architects and Designers, M&E Engineers, User, etc.) of the harmful effects of chemicals that exist inside buildings. The risk of poor Indoor Air Quality (IAQ) is increased by a lack of proficient knowledge of how numerous factors can contribute to poor IAQ, both during design, construction and after occupancy. As a result, the study set out to: research previous related research studies in the field of IAQ, identify the current status quo of IAQ in Kuwait, conduct a survey (questionnaires and interviews) with Kuwait construction professionals regarding IAQ issues and to find the barriers to implementing IAQ best practice in all stages of the project, and then finally, to develop a framework for achieving good IAQ in Kuwait housing projects. The findings revealed no documents written for Kuwait, that encompasses codes, standards, regulations and guidance for the implementation of good IAQ in Kuwait housing developments, or a framework for government enforcement of such. It was also revealed that there was a significant lack of awareness of indoor air pollutants and good IAQ both amongst occupants and construction professionals. The analysis also revealed that the status quo in the housing development process did not enable integration amongst the project team and stakeholders at the design stage, hence team member’s valuable input on achieving good IAQ at design stage is lost. Furthermore, the process did not emphasize the following at every stage of the project to ensure good IAQ: commissioning of the ventilation design and installation, which includes value engineering, proper sequencing and scheduling of activities to avoid dust or debris from contaminating the ventilation system, proper documentation and reporting to ensure the owner’s project objectives are documented, achieved, checked, and carried over to the next stage. The findings show that the barriers to achieving good IAQ in Kuwait housing developments are; cost and budget, government enthusiasm, lack of awareness, lack of enforceable codes and standards, lack of design integration, distrust of the competence level of local IAQ companies, habit and age, low level of IAQ education, and lack of training. While, the drivers of good IAQ in Kuwait housing are; the client/end-user, the government, architects, designers, IAQ consultants, construction professional societies, contractors and manufacturers. The developed and validated framework achieves the aim and objectives of the study by proposing strategies and actions for improving indoor air quality (IAQ) in Kuwaiti housing developments through increased integration, commissioning, proper and adequate sequencing and scheduling, and documentation at design, construction, and occupancy stages. Kuwait Environmental Protection Agency (KEPA), Kuwait Institute of Environmental Management (KIEM), Kuwait Municipality, and Kuwait Institute of Science and Research (KISR) were also suggested as the main bodies to drive the education, awareness, and training, of not only the construction industry but also the general population on good IAQ practices.
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20

Connick, Owen. "The fluid mechanics of hybrid ventilation." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/39347.

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A low-energy ventilation system is often incorporated as one of the major energy saving measures in sustainable building design. These systems often employ a hybrid strategy in which mechanical equipment, governed by a computer controlled building management system, is used to assist or manage a naturally-driven airflow - the latter occurring due to the density difference between warm air inside and cooler air outside the room. Hybrid ventilation flows are poorly understood and the principal aim of the research was to enhance our understanding of the fluid mechanics through complementary theoretical and experimental modelling. The research begins by comparing solely natural and solely mechanical ventilation of a room. The hybrid ventilation of a room is then considered under the combined effect of naturally occurring and mechanically imposed pressure differences, in which a mechanical fan imposes a fixed airflow rate through one vent, thereby altering the natural pressure distribution. Simplified theoretical models, to describe the ventilation airflow rate through a room and the resulting mean air temperature, were developed for solely natural ventila- tion, solely mechanical ventilation and, finally, hybrid ventilation. At each stage the theoretical model was compared with results from small-scale experiments, and good agreement was demonstrated. From the theoretical investigation, the neutral pressure level emerged as a key pa- rameter in determining the characteristics of the ventilation airflow. Moreover, it was found that the airflow rate through an open vent can be controlled remotely by managing the position of the neutral pressure level, and that this can be achieved by varying the magnitude of the mechanically imposed airflow rate. Experimental investigations revealed that, as the neutral pressure level approached the plane of a vent, quasi-steady pulsing flows and bi-directional or exchange flows were observed. The complicated fluid dynamics involved in these flows provides inspiration for significant future work.
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21

Mohd, Aris Mohd Shukri. "An assessment of indoor air quality at two contrasting location and building ventilation types in London." Thesis, King's College London (University of London), 2013. https://kclpure.kcl.ac.uk/portal/en/theses/an-assessment-of-indoor-air-quality-at-two-contrasting-location-and-building-ventilation-types-in-london(09e18aa4-683a-4a8b-baa7-a3dbb9b6e66e).html.

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Background: People spend most of their time indoors, in buildings such as schools and offices, as well as their homes. Recent interest in Indoor Air Quality (IAQ) suggests that the contribution of outdoor pollutants and indoor airborne particulate and gaseous pollutants may be responsible for the aggregation of a number of respiratory illnesses. Because of these possible health implications, it is important to understand the characteristics of each air pollutant inside/outside (I/O) the building and the variables affecting the degree of exposure to them. Objectives: This was achieved by long-term monitoring of a range of pollutants at two contrasting building types and locations within London. The transfer of pollutants(NOX, NO2, O3 and PMs) and particulate toxicity (PMTSP) within I/O sources over a wide range of meteorological condition, occupancy and seasonality was then characterised. Results 1 (Case 1): At naturally ventilated school building (urban background), paired long term monitoring revealed that the indoor gaseous pollutant concentration reacted differently according to occupancy and seasonality. Due to the fact that indoor NO concentration in the classroom was possibly dominated by indoor source, its presence was also believed to play an important role of reducing O3 in the classroom which mainly came attributed from outdoors during summer time. The increment of indoor larger (PM10) and coarse particle (PM2.5 – 10) was attributed when the building was actively used and identified to be linked from the certain type of classroom activity. However, a greater proportion of indoor PM2.5 was contributed from outdoors. Results 2 (Case 2): In contrast, a different pattern of diurnal variation profiles was observed in the mechanically ventilated office building (roadside site). An extreme indoor concentration of indoor NOX and NO2 monitored during rush hour on working-days were explained by the outdoor penetration. An extension study (building improvement) showed a clear reduction pattern in PM concentration; however it did not solve the high NO2 problem. Results 3: The novel time series of oxidative potential (OP) dataset established in this study highlightedaclear difference between the two sites. Indoor OP metrics in the roadside building recorded higher depletion rates compared to the urban background site. At urban background site, when indoor OP dataset were categorised and group as building occupancy and seasonal dependent, the indoor PM OP antioxidants metrics was found to have a higher depletion rate during occupied period and was observed during winter time, which particularly in particulate mass metric. At roadside site, interestingly, a significant decrease in PM-induced antioxidant depletion indoors, observed after the door upgrade. This study demonstrated that PM OP analysis from both internal and external sources is a useful tool for illustrating any changes in sources in the transfer of pollutants into a building. Conclusion: These monitoring results reveal the complexity of internal-external air quality relationship within building envelopes referring to ventilation type and location specificity. The ingress of outdoor pollution contribution in poor IAQ were also driven by other factors such as urban building orientation, the wide range of building occupancy and different set of ventilation types.
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22

Spasis, G. "Heating, ventilation and air conditioning system optimization : a study of the effect of climate, building design, system selection and control strategy on the energy consumption of a typical office building in London and Athens." Thesis, University College London (University of London), 2007. http://discovery.ucl.ac.uk/1445105/.

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Анотація:
The increasing demand for air conditioning in commercial buildings imposes a serious threat to Europe's CO2 reduction targets. Architects and engineers are therefore in a key position to help reduce the impact of buildings on the environment by taking appropriate decisions concerning the design of the building and the associated heating, ventilation and air conditioning (HVAC) system. The thesis studies the effect of a number of building and HVAC system related design factors on the energy performance of a notional air-conditioned office building employing either a variable air volume (VAV) system with terminal re-heaters, or a four-pipe fan coil unit (FCU) system with fresh air supply from a central plant, using mainly a dynamic simulation tool and the response surface methodology. The evaluation of the energy performance of the HVAC systems is for two types of climate, using typical weather data for London (UK) and Athens (Greece). It has been found that the design variables associated with the solar radiation through the transparent building elements and the internal heat gains should be the main concern of the building designer. On the other hand, the HVAC system engineer should give emphasis to the parameters associated with the plant performance and operation, as well as the temperature control set-points. It has been shown that it is possible to reduce the carbon emissions of the base case scenario by up to 88% depending on the HVAC system and the climate for which it is simulated. The carbon savings, however, are reduced by up to 22% where humidification is provided. This reduction differs depending on the HVAC system and the climatic conditions. The VAV system is more energy efficient than the FCU system, mainly due to the exploitation of the free cooling capacity of the outdoor air. The difference in carbon emissions between the two systems drops when both of them are simulated for the Athens as opposed to the London typical weather conditions. It has been found that it is possible to turn the carbon scales in favour of the FCU system when humidification to a high RH set-point is provided throughout the year, since the adjustment of the RH of the air is particularly energy wasteful for the VAV system.
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23

Collins, Andrew. "Evaluating reinforcement learning for game theory application learning to price airline seats under competition." Thesis, University of Southampton, 2009. https://eprints.soton.ac.uk/69751/.

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Applied Game Theory has been criticised for not being able to model real decision making situations. A game's sensitive nature and the difficultly in determining the utility payoff functions make it hard for a decision maker to rely upon any game theoretic results. Therefore the models tend to be simple due to the complexity of solving them (i.e. finding the equilibrium). In recent years, due to the increases of computing power, different computer modelling techniques have been applied in Game Theory. A major example is Artificial Intelligence methods e.g. Genetic Algorithms, Neural Networks and Reinforcement Learning (RL). These techniques allow the modeller to incorporate Game Theory within their models (or simulation) without necessarily knowing the optimal solution. After a warm up period of repeated episodes is run, the model learns to play the game well (though not necessarily optimally). This is a form of simulation-optimization. The objective of the research is to investigate the practical usage of RL within a simple sequential stochastic airline seat pricing game. Different forms of RL are considered and compared to the optimal policy, which is found using standard dynamic programming techniques. The airline game and RL methods displays various interesting phenomena, which are also discussed. For completeness, convergence proofs for the RL algorithms were constructed.
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24

Simon, Margit Hildegard. "Ocean and land climate dynamics off southeast Africa during the late Pleistocene : a multi-proxy approach." Thesis, Cardiff University, 2014. http://orca.cf.ac.uk/69701/.

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The Agulhas Current transport of heat and salt from the Indian Ocean into the South Atlantic around South Africa (Agulhas leakage), can affect the Atlantic Meridional Overturning Circulation (AMOC) and, thus, influence global climate. Upper water column reconstructions in the southwest Indian Ocean over the past 100 kyr based on marine sediments from the core region of the Agulhas Current suggest that surface ocean temperature, salinity and planktonic foraminiferal assemblage records from the Agulhas Current exhibit high variability on orbital to millennial timescales. A high degree of similarity in this variability could also be identified in the Agulhas leakage records in the South Atlantic which suggests that changes in the Agulhas leakage can be partly explained by upstream variability in the Current itself. The results of a benthic stable isotope record from the southwest Indian Ocean over the past 270 kyr gives evidence that during glacial periods as well as during Northern Hemisphere Cold Stadials Southern Component Waters substituted for North Atlantic Deep Waters. The recorded hydrographic variability in the deep southwest Indian Ocean is explained in terms of a less vigorous AMOC exporting a reduced amount of NADW into the Southern Hemisphere and/or at shallower depth causing the observed changes in the deep water inventory. A multiproxy data and model integration approach reveals that phases of more humid southeast Africa climate were driven by southward oscillations of the Intertropical Convergence Zone and its associated rain belt over the past two glacial-interglacial cycles. Low-latitude summer insolation changes paced by orbital precession explain the long-term climate variability whereas abrupt climate oscillations in the northern high latitudes are the main driver for the observed millennial-scale wet phases. Southeast African climate variability seems to have been coupled, and anti-phased, with the East Asian Summer Monsoon during the late Pleistocene. Agulhas Current sea surface temperatures changes did not exert a primary control on southeast African hydrology.
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25

Irfan, Muhammad. "An integrated, multicriteria, Spatial Decision Support System, incorporating environmental, social and public health perspectives, for use in geoenergy and geoenvironmental applications." Thesis, Cardiff University, 2014. http://orca.cf.ac.uk/69771/.

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A new Spatial Decision Support System (SDSS) has been designed and developed to address a wide spectrum of semi-structured spatial decision problems. These problems are related to site selection, site ranking and impact assessment. The proposed SDSS is conceptualised as a holistic, informed and impact-based multicriteria decision framework. The system has been developed using the .NET C# programming language and open source geoinformatics technologies such as DotSpatial and SpatiaLite. A combination of existing Multi Criteria Decision Analysis (MCDA) and Artificial Intelligence (AI) techniques, with a few novel variations have been developed and incorporated into the SDSS. The site selection module utilises a theme-based Analytical Hierarchy Process (AHP) and Weighted Linear Combination (WLC). Two site ranking techniques have been introduced in this research. The first technique is based on the systematic neighbourhood comparison of sites with respect to key indicators. The second technique utilises multivariate ordering capability of the one-dimensional Self-Organizing Maps (SOM) to rank the sites. The site impact assessment module utilises a theme-based Rapid Impact Assessment Matrix (RIAM). A spatial variant of the General Regression Neural Networks (GRNN) with a genetic algorithm for optimisation has been developed for the prediction and regression analysis. A number of other spatial knowledge discovery and geovisual-analytics tools have been provided in the system to facilitate spatial decision making process. An application of the SDSS has been presented to investigate the potential of Coalbed Methane (CBM) development in Wales, UK. Most potential sites have been identified by utilising the site selection and site ranking tools of the developed SDSS. An impact assessment has been carried out on the best sites by using Rapid Impact Assessment Matrix. Further analysis has uncovered the spatial variability expected in the potential impacts of the sites, considering key indicators. The application has demonstrated that the developed system can help the decision makers in providing a balanced regime of social, environmental, public health and economic aspects into the decision making process for engineering interventions. The generic nature of the developed system has extended the concept of Spatial Decision Support System to address a range of spatial decision problems, thereby enhancing the effectiveness of the decision making process. The developed system can be considered as a useful modern governance tool, incorporating the key factors into decision making and providing optimal solutions for the critical questions related to energy security and economic future of the region.
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26

Євсеєнко, Олег Миколайович. "Моделі та методи енергозберігаючого керування розподіленими тепловими об'єктами з використанням систем з прогнозуючим фільтром". Thesis, НТУ "ХПІ", 2018. http://repository.kpi.kharkov.ua/handle/KhPI-Press/33815.

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Дисертація на здобуття наукового ступеня кандидата технічних наук (доктора філософії) за спеціальністю 05.13.03 «Системи та процеси керування» (151 – Автоматизація та комп’ютерно інтегровані технології) – Національний технічний університет «Харківський політехнічний інститут» Міністерства освіти і науки України, Харків, 2018 р. Дисертацію присвячено аналізу систем керування розподіленими тепловими об’єктами, визначенню їх недоліків для розробки нових енергоефективних методів керування теплопостачанням адміністративних та офісних будівель з використанням систем з прогнозуванням. Розглянуто проблеми розробки енергозберігаючого керування тепловими об’єктами. Проаналізовано розподілені теплові об’єкти. Проведено класифікацію теплових об’єктів керування залежно від кількості використовуваних видів енергоносіїв, структури, режиму роботи опалювального обладнання. Досліджено існуючі методи синтезу систем керування розподіленими тепловими об’єктами та систем керування тепловою енергією. Розглянуто основні чинники, які впливають на температуру в приміщенні. Проаналізовано регулятори з прогнозуванням. Досліджено існуючі тенденції розвитку методів енергозберігаючого керування, які застосовуються у системах теплопостачання. Встановлено, що існуючі регулятори температури з прогнозуванням підтримують температуру в приміщенні в діапазоні від +19 °C до +22 °C з точністю ± 1 °C. Також встановлено, що регулятори, основані на погодозалежному, ПІД- та двопозиційному законах керування, скорочують витрати на енергоспоживання на 15%, а використання регуляторів з прогнозуванням зменшує енергоспоживання на 25–35%. Обґрунтовано перспективність розробки енергозберігаючих методів керування розподіленими тепловими об’єктами з прогнозуванням. Проведено аналіз поведінки розподілених теплових об’єктів керування, їх властивостей. Сформульовано вимоги до синтезу енергозберігаючих законів керування тепловими об’єктами. Визначено область досяжності, початкові і граничні умови при початковій стадії дослідження і моделювання об’єкта для знаходження ефективного рішення. Теоретично обґрунтовані передумови і обмеження для розробки методів енергозберігаючого керування. Проведено класифікацію регуляторів для керування розподіленими тепловими об’єктами в залежності від величини відношення часу транспортного запізнення до часу перехідних процесів. Розроблено алгоритм розв’язання задачі розрахунку розподілення тепла всередині офісного приміщення за допомогою моделі в середовищі ANSYS. Розроблено методику поділу структури приміщення на n об’єктів з зосередженими параметрами з однаковими властивостями простору. Розглянуті основні проблеми керування розподіленими тепловими об’єктами. Набув подальшого розвитку метод керування тепловим об’єктом з розподіленими параметрами за допомогою ступінчастої функції. Розроблено формули, які дозволяють перейти від керування об’єктом з зосередженими параметрами до керування об’єктом з розподіленими параметрами. Розроблено спосіб програмного керування тепловим об’єктом з розподіленими параметрами за допомогою широтно-імпульсної модуляції та прогнозуючого фільтра, де вектор цільової функції формується з помилки керування в поточний момент часу і прогнозованої помилки неузгодженості, що визначається як різниця між заданою температурою і температурою моделі регулятора. Розроблено мікроконтролерну систему керування теплопостачанням, яка складається з підсистеми збору інформації, підсистеми видачі керуючого впливу, центрального обчислювача та пульту керування. Встановлено, що для діагностування несправностей підсистеми збору інформації та видачі керуючого впливу повинні бути замкнуті в кільце. Розроблено алгоритми діагностики справності ліній даних, керування температурою об’єкта та реєстрації перехідних характеристик об'єкта керування. Встановлено, що реалізацію керуючого впливу у вигляді ступінчастої функції можна здійснювати за допомогою паралельного з’єднання нагрівачів різних потужностей. Запропоновано перейти до керування тепловим об’єктом за допомогою широтно-імпульсної модуляції, при якому регулюючий елемент працює в ключовому режимі через наявність недоліків у реалізації керуючого впливу у вигляді ступінчастої функції. На основі вимірів на реальному об’єкті побудована повна тривимірна модель приміщення з урахуванням зовнішніх обводів і точної внутрішньої геометрії. Побудована об’ємна розрахункова сітка з гексаедрів. Задані граничні умови з урахуванням системи опалення, системи вентиляції повітря, теплопровідності стін, температури зовнішнього повітря. Отримано перехідні криві впливу зовнішньої температури, вентиляції з температурою повітря, що дорівнює 20 °C, нагрівача потужністю 1.75 кВт на температуру в приміщенні. Створено програму-макрос (udf файл) на мові С у середовищі ANSYS для проведення експерименту. Задані умови для проведення моделювання: зовнішня температура змінюється від мінус 7 °С до + 5 °С, залежно від часу доби, початкова температура повітря в приміщенні + 18 °С, швидкість приточної та витяжної вентиляції 0.018 кг / с, температура приточної вентиляції + 20 °С. Проведено експеримент з підтримання заданого добового температурного режиму в приміщенні: з 00:00 до 08:00 + 10 °С, з 09:00 до 17:00 + 18 °С, з 18:00 до 00:00 + 15 °С. Порівняно розроблений метод ШІМ-регулювання з прогнозуванням з найбільш поширеними: двопозиційним регулюванням з гістерезисом ± 2 ° C, двопозиційним регулюванням без гістерезису і ПІД-регулюванням. За результатами моделювання встановлено, що найвищу точність показав метод ШІМ-регулювання з прогнозуванням. Найменш ефективним виявився метод двопозиційного регулювання з гістерезисом, рівним ± 2 ° C, який завдяки наявності інерції теплового об’єкта перевищив задану температуру в приміщенні. Отримано сумарний час роботи нагрівача протягом доби. Методи регулювання температурою за допомогою ПІД регулятора і регулятора з прогнозуванням показали приблизно однаковий час роботи нагрівача (39.89% проти 39.24%). Відповідно до місячної вартості за 1 кВт електроенергії, загального часу роботи нагрівача, потужності обчислено витрати на опалення для приміщень з однозмінним режимом роботи без вихідних для добового та місячного режимів. Встановлено, що відмова від безперервної роботи нагрівача і застосування регулятора з прогнозуванням дозволить зменшити час роботи опалювального обладнання на 56%: з 24-х до 10.5 год. За результатами моделювання побудовано температурні зони приміщення, які дають вихідну інформацію, в яких точках приміщення необхідно розташовувати датчики температури. Для експериментальних досліджень об’єктами керування обрано порожнистий сталевий стержень з розмірами: довжина 35.5 см, зовнішній діаметр 3.2 см, внутрішній діаметр 2.8 см, з намотаним на одному кінці нагрівачем довжиною 8.2 см від початку труби опором 19 Ом, і стерилізатор ГП-80. Для здійснення натурного експерименту зібрано експериментальну установку на базі мікроконтролера ATMega16, використано датчики DS18B20, мікросхему пам’яті AT24C256B-PU. Написано програму керування температурою об’єкта для мікроконтролера ATMega16. Для кожного з обраних об’єктів керування отримані перехідні криві та проведено експерименти з підтримання заданих температурних умов. Результати досліджень підтвердили правильність теоретичних передумов, покладених в основу розробки апаратно-програмного комплексу, і перспективність цього напрямку. Вирішено задачу пошуку оптимального співвідношення параметрів потужності нагрівача й інтервалу прогнозування за допомогою методу найменших квадратів. Встановлено, що для зменшення помилки регулювання імпульс керуючого впливу слід виробляти на початку інтервалу програмного регулювання з урахуванням величини перерегулювання. Результати наукових досліджень впроваджені в практику проектування систем автоматичного керування тепловими об’єктами, технологічними процесами підприємства ТОВ «ВО ОВЕН» (м. Харків). Матеріали дисертації використовуються в лекційних курсах «Теорія автоматичного керування» і «Програмні засоби систем керування» на кафедрі «АіУТС» НТУ «ХПІ».
Thesis for granting the Degree of Candidate of Technical sciences (PhD degree) in specialty 05.13.03 «Management systems and processes» (151 – Automation and computer-integrated technologies) National Technical University «Kharkiv Polytechnic Institute» of Ministry of Education and Science of Ukraine, Kharkiv, 2018. The thesis is devoted to the analysis of distributed thermal objects control using prediction systems to determine their disadvantages and development of new energy-efficient heat control methods for administrative and office buildings. The problems of thermal objects energy-saving control development are considered. Distributed thermal objects are analyzed. The author suggests a classification of thermal objects according to the number of used energy sources, structure, working mode of the heating equipment. Existing synthesis methods of control systems for distributed thermal objects and thermal energy control systems are investigated. The main factors affecting temperature in premises are considered. The regulators with prediction are analyzed. The existing tendencies in the development of energy saving control methods applied in heat supply systems are explored. It has been found that existing temperature controllers with prediction maintain temperature in the premises in the range from +19 °C to +22 °C with accuracy ± 1 °C. It has also been demonstrated that regulators based on weather-dependent, PID-, on–off control laws reduce energy consumption by 15%, using regulators with prediction reduces power consumption by 25-35%. Perspective of energy-saving methods control of distributed thermal objects with prediction is substantiated. The author has carried out an analysis of the behavior and properties of distributed thermal control objects. The requirements for the synthesis of energy-saving thermal objects control laws are formulated. Feasible region, initial and boundary conditions at the initial stage of research, modeling of the object for finding an effective solution have been determined. Prerequisites and constraints for the development of methods of energy saving management are theoretically justified. A classification of distributed thermal objects regulators, depending on the ratio of the transport delay time to the time of transient processes, has been carried out. The author developed an algorithm for solving the problem of calculation the heat distribution inside an office premises. A model of the room in the ANSYS environment is created. The method of dividing the structure of the premises into n objects with lumped parameters with the same properties of space is developed. The basic problems of distributed thermal objects control are considered. The control method of thermal object with distributed parameters using a step function have been further developed. Formulas that allow to refuse from an object with lumped parameters control to an object with distributed parameters control has been developed. The author developed a method of thermal object with distributed parameters control using pulse-width modulation with prediction filter, where the target function vector is formed from the control error at the current time and the predicted mismatch error, that is defined as the difference between the given temperature and the temperature of the regulator model. A microcontroller system of heat supply control, that consists of a subsystem of getting information, a subsystem of issuing control influence, central controller and control panel have been developed. It has been established that in order to identify the refusal of the subsystem of information gathering and the issuance of controlling influence, they must be closed in the circle. The algorithms of diagnosing the data linesї efficiency, controlling the temperature of the object and recording the transient characteristics of the control object are developed. It is established that the implementation of control influence in the form of a stepped function can be carried out with the help of a parallel connection of heaters of various power. It is suggested to control the temperature of a thermal object with pulse-width modulation, in which the control element operates in key mode due to the disadvantages of implementing a control effect in the form of a stepped function. On the basis of measurements on a real object, a complete three-dimensional model of the room taking into account external contours and exact internal geometry was constructed. Volumetric netting of hexahedrons was built. Boundary conditions taking into account the heating system, ventilation system, heat conductivity of walls, the temperature of the outside air were specified. Transient curves of influence on the room of external temperature, ventilation with air temperature equal to 20 °C, a 1.75 kW power heater temperature were obtained. A program macro (udf file) on C language in the ANSYS environment for the experiment was created. The conditions for the simulation: the external temperature varies from minus 7 °C to plus 5 °C, depending on the time of day, the initial air temperature in the room +18 °C, the speed of intake and exhaust ventilation 0.018 kg/s, the temperature of the intake ventilation + 20 °C were specified. An experiment to maintain a setting daily temperature mode in the room: from 00:00 to 08:00 + 10 °С, from 9:00 to 17:00 + 18 °С, from 18:00 to 00:00 + 15 ° С was conducted. Method of PWM regulation with prediction to the most common: twoposition regulation with hysteresis ± 2 ° C, two-position regulation without hysteresis and PID-regulation were compared. According to the simulation results, the PWM control with prediction the highest accuracy was exhibited. The least effective method was two-position regulation with hysteresis equal to ± 2 °C, which due to the inertia of the thermal object exceeded the given temperature in the room. The total time of the heater operation during the day is obtained. The methods of temperature control with the PID regulation and PWM with prediction control roughly the same time of operation of the heater (39.89% vs. 39.24%) were showed. According to the monthly cost of 1 kW of electricity, the total operating time of t he heater, heater power for the heating costs for rooms with one-shift operating mode without a weekend for day and month modes were calculated. It has been established that the refusal of continuous operation of the heater and using regulator with prediction will reduce the operating time of the heating equipment by 56%: from 24 to 10.5 h. According to the simulation results, the temperature modes of the premises that give the source information in which points of the room it is necessary to place the temperature sensors are obtained. For experimental studies, a hollow steel rod with dimensions: length 35.5 cm, outer diameter 3.2 cm, internal diameter 2.8 cm, wound on one end with a heater length of 8.2 cm from the beginning of the tube with a resistance of 19 Ohms, and sterilizer GP-80 were selected. For a real experiment, an experimental installation based on the ATMega16 microcontroller, sensors DS18B20, microchip memory AT24C256B-PU was used. A program of the object temperature control on the ATMega16 microcontroller is written. For each of the selected control objects transition curves were obtained and experiments of maintaining the specified temperature conditions were carried out. The correctness of the theoretical prerequisites for the development of the hardware and software complex was confirmed by the results of the research. The problem of finding the optimal ratio of heater power parameters and forecasting interval using the least squares method is solved. It was found that to reduce the control error, the control impulse pulse should be made at the beginning of the program control interval, taking into account the amount of overshoot. The results of scientific research were introduced into the practice of designing systems for automatic control of thermal objects, technological processes of the enterprise VO OWEN (Kharkiv). The materials of the dissertation are used in lecture courses "Theory of automatic control" and "Software tools of control systems" at the department automation and control systems NTU "KhPI".
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27

Євсеєнко, Олег Миколайович. "Моделі та методи енергозберігаючого керування розподіленими тепловими об'єктами з використанням систем з прогнозуючим фільтром". Thesis, НТУ "ХПІ", 2018. http://repository.kpi.kharkov.ua/handle/KhPI-Press/33812.

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Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.13.03 – системи та процеси керування.  Національний технічний університет «Харківський політехнічний інститут», Харків, 2018. Дисертація присвячена розробці й удосконаленню методів енергозберігаючого керування розподіленими тепловими об’єктами для застосування в існуючих і нових системах теплопостачання. Запропоновано спосіб керування тепловими об’єктами з розподіленими параметрами з прогнозуванням, де як керуючий вплив використовується ШІМ-сигнал. Набув подальшого розвитку спосіб керування тепловими об’єктами з розподіленими параметрами з прогнозуванням, з керуючим впливом типу ступінчастої функції. Запропоновано формули, які дозволяють перейти від керування об’єктом із зосередженими параметрами до керування об’єктом з розподіленими параметрами в n точках простору, з використанням p нагрівачів. У середовищі ANSYS на основі вимірів на реальному об’єкті з використанням методу скінченних елементів побудована імітаційна модель приміщення. На цій моделі застосовано алгоритми керування температурним полем з використанням ШІМ-керування з прогнозуванням, ПІД-регулятора, двопозиційного керування та промодельована безперервна робота нагрівача. За допомогою розробленого програмно-апаратного комплексу на базі мікроконтролера AtMega 16 для обраних об’єктів керування – сталевого порожнистого стержня і камери стерилізатора – здійснено експериментальні дослідження для підтримання заданої температури за допомогою ШІМ-керування з прогнозуванням. Результати досліджень засвідчили високу ефективність роботи методу з урахуванням зовнішніх збурень і підтриманням температури з точністю не більше ± 1 % від заданого значення температури.
The thesis on Candidate Degree in Technical Sciences: Specialty 05.13.03 – management systems and processes. – National Technical University «Kharkov Polytechnic Institute», Kharkov, 2018. The thesis is devoted to the development and improvement of energy-efficient control methods of distributed thermal objects for using in heat supply systems. The thesis proposes a control method of thermal objects with distributed parameters with prediction filter, where the PWM signal is used as the control action. The method of controlling thermal objects with distributed parameters with prediction using the step function as control effect has been further developed. The paper presents a formalized description of predictive control methods that allow to control temperature of an object with distributed parameters instead of object with lumped parameters temperature control at n points with p heaters. A simulation room model based on measurements of the room and the finite element method in the ANSYS environment was constructed. Using developed predictive controller, experiments of maintaining the assigned daily temperature mode were carried out. The developed method of PWM predictive control with continuous control, two-position, PID-control was compared. Experiments of maintaining the set temperature of the steel hollow rod and the sterilizer chamber using the developed software and hardware complex, based on the microcontroller AtMega 16 and PWM with prediction control method, were carried out.
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28

Liu, Pei-Chun. "A modelling study of segmentation of naturally ventilated tall office buildings in a hot and humid climate." Thesis, University of Nottingham, 2012. http://eprints.nottingham.ac.uk/13262/.

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The prevailing paradigm in indoor environment control of office buildings often excludes natural ventilation, due to the fact that its dynamic nature may not be compatible with the close control of mechanical conditioning systems. The challenges will be greater in terms of the potential high magnitudes of wind and buoyancy forces at high levels of tall buildings. This research is concerned with the prospect of tall office buildings that are purely naturally ventilated. It is proposed that “segmentation” might offer the least risky approach for natural ventilation design of non-domestic tall buildings. Accordingly, the generic design procedure are proposed for investigating the influence of segmentation on ventilation air flows: firstly, the single-cell envelope flow model is adopted to evaluate the steady-state bulk flows through openings under a specified design condition; secondly, dynamic thermal modelling with an air flow network module is used, because of the particular importance of the coupling between the airflow and thermal process for evaluating the year-round ventilated cooling potential of targeted spaces. The chosen thermal model utilizes a multi-cell airflow network model (AFN) since the targeted buildings can no longer be described by a single-cell model; thirdly, computational fluid dynamics (CFD) simulation is suggested in the later design stage to cope with insufficient resolution of local airflow distribution in previous modelling stages; finally, the overall performance of comfort ventilation is then interpreted in relation to adaptive thermal comfort theory by the use of Building Bioclimatic Charts, which offers a way of rapidly testing whether or not natural ventilation is likely to produce comfortable conditions. The novelty of this work lies not in the methodology, which uses available modelling tools, but in the evaluation of naturally ventilated tall buildings with reference to segmentation in the climatic context of Taiwan. The effect of segmentation is evaluated by comparing the overall ventilation performance under three different building configurations, namely the isolated, segmented and non-segmented tall buildings. The overall objectives are to determine whether the magnitudes of air flow rates and the resultant flow velocity can achieve the desired comfort ventilation over a range of specified conditions. Potential scenarios where the design goals may not be ensured are identified. The feasibility for naturally ventilated tall office buildings in hot and humid climates is clarified accordingly.
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29

Bol, Bullen A. D. "A pervaporation membrane absorption cooling heating system." Thesis, University of Nottingham, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.289081.

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30

Nardoni, Chiara. "Diffusion maps in the Subriemannian motion group and perceptual grouping." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amslaurea.unibo.it/6971/.

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Il presente lavoro è motivato dal problema della constituzione di unità percettive a livello della corteccia visiva primaria V1. Si studia dettagliatamente il modello geometrico di Citti-Sarti con particolare attenzione alla modellazione di fenomeni di associazione visiva. Viene studiato nel dettaglio un modello di connettività. Il contributo originale risiede nell'adattamento del metodo delle diffusion maps, recentemente introdotto da Coifman e Lafon, alla geometria subriemanniana della corteccia visiva. Vengono utilizzati strumenti di teoria del potenziale, teoria spettrale, analisi armonica in gruppi di Lie per l'approssimazione delle autofunzioni dell'operatore del calore sul gruppo dei moti rigidi del piano. Le autofunzioni sono utilizzate per l'estrazione di unità percettive nello stimolo visivo. Sono presentate prove sperimentali e originali delle capacità performanti del metodo.
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31

Fyfe, Cameron D. "Structural and biophysical characterisation of Escherichia coli alpha-2-macroglobulin and its interaction with penicillin binding protein 1C." Thesis, University of Glasgow, 2015. http://theses.gla.ac.uk/6971/.

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The alpha-2-macroglobulin superfamily consists of large multi-domain proteins that are activated by protease cleavage. One arm of this family consists of protease inhibitors that undergo a large conformational change upon protease cleavage, simultaneously physically trapping the cleaving protease and covalently linking to it via a thioester bond. However, there is little mechanistic understanding of how protease cleavage activates the conformational changes that lead to protease inactivation. These protease inhibitors are found in tetrameric, dimeric and monomer forms within eukaryotic blood/lymph fluid. The recently described Escherichia coli alpha-2-macroglobulin (ECAM) is a periplasmic, inner membrane anchored protease inhibitor. The gene encoding ECAM, yfhM, is found within an operon alongside pbpC, which encodes penicillin binding protein 1C. These two proteins have been proposed to function in defence and repair against host proteases with ECAM acting to inhibit proteases that have breached the outer membrane and Pbp1C repairing damage to the peptide linkages within the peptidoglycan layer. This thesis describes the structural and biophysical characterisation of ECAM and an investigation into the role of Pbp1C in ECAM function. In order to gain insight into the mechanism through which protease cleavage activates ECAM we used a combination of X-ray crystallography, small angle X-ray scattering and analytical ultracentrifugation to characterise the conformational changes that occur on protease cleavage. The X-ray structure of protease cleaved ECAM revealed a putative mechanism of activation and conformational change essential for protease inhibition. In this competitive mechanism, protease cleavage of the bait-region domain results in the untethering of an intrinsically disordered region of this domain which disrupts native inter-domain interactions that maintain ECAM in the inactivated form. Owing to the similarity in structure and domain architecture of ECAM and human α-2-macroglobulin, this protease-activation mechanism is likely to operate across the diverse members of this group. Further to this, it was shown that ECAM is processed in vivo, existing largely as truncated forms in growing E. coli cells. Interestingly, Pbp1C plays a key role in ECAM processing, with cell lacking pbpC showing an accumulation of full-length and dimeric forms of ECAM.
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32

Sullivan, W. G. "Exploring the importance of links between health behaviours for economic evaluations of behaviour-change strategies : a case study considering the link between smoking cigarettes and drinking alcohol." Thesis, University of Sheffield, 2014. http://etheses.whiterose.ac.uk/6971/.

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Links between health behaviours are potentially of great importance for cost-effectiveness estimates in economic evaluations of behaviour change strategies. This thesis investigates bias in economic evaluations due to the omission of links between health behaviours. A framework to evaluate the health costs and consequences of behaviour change strategies while accounting for links to other health-related behaviours is proposed, and tested using a case study of the link between tobacco and alcohol use. There is strong evidence of correlation between alcohol use and tobacco use. Nevertheless, while many economic evaluations of interventions for alcohol and tobacco behaviour change have been conducted and used to inform resource allocation decisions, none have considered implications of links between the two behaviours. Assumptions about behaviour beyond typical trial endpoints in historical economic evaluations have in general been based on limited follow-up data. Analysis of the joint dynamics of tobacco and alcohol use employing large-scale longitudinal survey data is used in this thesis as an alternative to inform assumptions about long-run smoking behaviour and its link to alcohol use, in a de novo individual-level simulation to appraise the cost-effectiveness of smoking cessation interventions. Smoking behaviour is found to be persistent and dynamically linked to alcohol use, but also influenced by numerous other factors, including unobserved time-invariant person-specific characteristics which determine the propensity to smoke. The ability of smoking cessation interventions to permanently reduce the propensity to smoke is important for their long-run cost-effectiveness. In the absence of data on this effect, historical economic evaluations may have misinformed decision makers. There is a need for robust and tested assumptions about long-term behaviour and case by case consideration of the importance of inter-behavioural links in future economic evaluations of behaviour change strategies, and for further investigation into the dynamics and interrelation of health-related behaviours.
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33

Vannelli, Uva Michele <1981&gt. "I tre libri di salmi vespertini a otto voci (opp. I, VII e XI) di Giovanni Paolo Colonna." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/6971/.

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Le tre raccolte di salmi da vespro a otto voci nello stile pieno di Giovanni Paolo Colonna (Bologna 1637-1695), pubblicate rispettivamente nel 1681, nel 1686 e nel 1694 (opp.I, VII e XI), costituiscono un oggetto di studio privilegiato nell’ambito della ricca produzione a stampa dell’autore: in primo luogo, esse ebbero ampia e favorevole recezione, come testimoniano la diffusione degli esemplari, le ristampe, le copie manoscritte ricavate dalle edizioni; in secondo luogo, la fortuna postuma del compositore fu legata in buona parte alla sua musica sacra a doppio coro e, in particolare, al favore riscosso dai suoi libri di salmi; infine, l’analisi delle tre raccolte consente di confrontare le risorse tecniche e stilistiche messe in opera da Colonna in composizioni afferenti a uno stesso genere ma risalenti a periodi diversi. La dissertazione è articolata in tre parti: nella prima sono presi in esame gli ordinamenti liturgici secenteschi relativi alla celebrazione dei vespri, onde illustrare la cornice rituale alla quale i salmi di Colonna erano destinati, e si passano in rassegna alcune definizioni di stile pieno e di contrappunto a otto voci desunte dalla trattatistica coeva. La seconda parte è dedicata alla lettura storico-critica delle opp. I, VII e XI nel contesto generale della produzione dell’autore. La terza parte contiene l’edizione integrale dell’opera VII e XI, nonché una scelta di brani tratti dall’op. I.
The three collections of psalms for vespers for eight voices in the stile pieno by Giovanni Paolo Colonna (Bologna 1637-1695), published in 1681, in 1686 and in 1694 (op. nos. I, VII and XI) respectively, are a favourite topic of study within the vast printed output of the composer. First, they were well received everywhere, as shown by the circulation of the copies, the reprints and the handwritten copies taken from the editions. Secondly, the composer's posthumous fame was linked for the most part to his sacred music for double choir and, in particular, to the success of his books of psalms. Finally, the analysis of the three collections allows the comparison of the technical and stylistic resources used by Colonna in compositions belonging to the same genre but dating back to different periods. The dissertation is divided into three parts: the first considers the seventeenth century liturgical regulations concerning the celebration of vespers, in order to illustrate the liturgical context for which Colonna’s psalms were intended, and some definitions of stile pieno and counterpoint for eight voices taken from contemporary treatises are reviewed. The second part is devoted to the historical-critical examination of op. nos. I, VII and XI in the general context of the composer’s output. The third part contains the complete edition of op. nos. VII and XI, as well as a selection of pieces from op. I.
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34

Juárez, Aníbal Damián. "Gestión ambiental en Mendoza y responsabilidad social empresaria." Bachelor's thesis, Universidad Nacional de Cuyo. Facultad de Ciencias Económicas, 2014. http://bdigital.uncu.edu.ar/6971.

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Las organizaciones de cualquier tipo, ya sea con fines de lucro o sin él, siempre persiguen un fin o un conjunto de metas, un conjunto de propósitos que hacen al existir de las mismas, esto equivale a una intencionalidad en su actuar. Estos objetivos pueden ser agrupados en una serie ordenada dependiendo de su naturaleza; ordenamiento a su vez jerárquico y con diferentes periodos de tiempo para alcanzarlos. A lo largo de la existencia de la Ciencia Administrativa, diversos autores han definido a las organizaciones dependiendo de sus circunstancias particulares, nacionalidades o marcos temporales, existiendo por lo tanto sutiles diferencias; no obstante el concepto de ambiente siempre ha sido incluido en las mismas.
Fil: Juárez, Aníbal Damián. Universidad Nacional de Cuyo. Facultad de Ciencias Económicas.
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35

Marshall, Edwin Kenneth. "Ontstaan en ontwikkeling van het Surinaams nationalisme natievorming als opgave /." [Delft : Amsterdam : Eburon] ; Universiteit van Amsterdam [Host], 2003. http://dare.uva.nl/document/69731.

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36

Kruger, Johannes Jacob. "State provision of social security : some theoretical, comparative and historical perspectives with reference to South Africa." Thesis, Stellenbosch : Stellenbosch University, 1992. http://hdl.handle.net/10019.1/69771.

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Анотація:
Thesis (MComm)--Stellenbosch University, 1992.
ENGLISH ABSTRACT: Societies are imaginative when setting up non-marl\et responses to deal v1ith insecurity and deprivation. The result is that there are many different services (such as income support, personal welfare services, education, health care and housing) catering for the very general objective of providing security. In addition, a variety of institutions can, and do, provide these services. While the traditional theory of public goods and e::...1ernalities does not provide clear justification for increased state provision of these services (in contrast to market, family, community and employer provision), increased state provision and coordination do seem to be a clear trend both from historical and comparative perspectives. Furthermore, this increased role of the state can be interpreted as representing a reassignment of the traditional roles of other institutions (noted above) to the state. The above trend can be rationalized on economic grounds as being the result of the changing nature of societies which affects the viability of different institutions In the provision of social services. Economic devt~lopment affects the cost of production of social services by different institutions differently. Taking a more in depth view of the costs of production, there are grounds to believe that the comparative advantage of the state in the provision of these_ services grows- a-s economic development takes place. "Nationalization" of the provision of services providing social security as economic development takes place can thus be seen as a stylized fact of economic development, and as representing an adjustment which can be efficiency enhancing. lt is from this perspective that the issue of the affordabiiity of increased social provision in developing countries should be approached. The South African experience provides further evidence of the increasing pressures, over time, for greater state provision of social security. The experience also, how . .:wer, furnishes examples of how in a specific situation these forces can be obstructed by speciric political institutions and how social policy can fail to adjust to changing circumstances. This resulted in the current unequal access to social services, the inequality of benefit levels and the incomplete coverage of risks faced by people in the South African economy. In spite of the incompleteness of the South African social safety net and the inequality which it reflects, fiscal and macroeconomic constraints seem to limit the possibilities for eAtending the safety net and for making it more just These constraints imply, and have resultoo in, the lowering of benefits to the previously privileged _;-( and an adjustment in the nature of benefits, leading to a focus on lower cost services which offer high rates of return. Current demands and envisaged changes in the spht?re of social policy, especially those surrounding a national pension system with universal coverage and G:·.tensive speci31 employm.3nt programmes, however, indicate the strength of the forces making for increase:d "nationali:ation" of income support and other social services. How the perceived fiscal constraints can be reconciled with the alleged rationality of a growing role for the South African state in social provision remains a question. The very general response of this study needs to be evaluated by looking in more d.:.tail at specific programmes and specific aspects of insecurity.
AFRIKAANSE OPSOMMING: Samelewings is verbeeldingryk met die daarstelling van nie-markgeorienteerde installings om armoede en 'n gebrek aan bestaanssekerheid die hoof te bied. Daarom is daar 'n verskeidenheid dienste (soos inkomsteversekering, persoonlih:e welsynsdienste, gesondheid, onderwys en behuising) om die baie algemene behoefte aan bestaanssekerheid aan te spreek. Daar is dan ook 'n hele verskeidenheid instellings wat hierdie dienste voorsien, en kan voorsien. Alhoewel die tradisionele teorie van publieke goedere en ekstemaliteite nie voldoende regverdiging vir groeiende staatsvoorsiening van hierdia dlenste (in teenstelllng met verskafflng deur markte, families, gemeenskappe en werkgewers) daarstel nie, blyk dit dat toenemende staatsvoorslening uit 'n historiese sowel as vergelykende perspektief 'n duid&like tendens verteenwoordlg. Verder kan die groeiende rol van die staat in hierdle steer oak gesit:m word .:ts die gevolg van die hertoewysing van tradisionele rolle van ander instellings (soos hierbo genoem) aan die staat. Hierdie tend ens kan op ekonomiese gronde gerasionaliseer word as die gevolg van die veranderende aard van samelewlngs wat die ekonomiese lewensvatbaarheid van instellings in die voorsiening van sosiale dienste beinvloed. Ekonomiese ontwikkeling affekteer verskillende instellings, en daarom die produksiekoste van sosiale dienste deur die instellings voorsien, op uiteenlopende maniere. lndien 'n bree konsep van produksiekoste gebruik word is dit moontlik am te argumenteer dat die ataat se vergelykende voordeel in die voorsiening van hierdie dienste toeneem soos 'n land ekonomies ontwikkel. "Nasionalisering" van die dienste wat sosiale sekuriteit daarstel kan dan gesien word as een van die basiese neigings wat met ekonomiese ontwikkeling geassosieer kan word. sowel as 'n aanpassing wat ekonomiese doeltreffendheid verbeter. Hierdle perspektief Is die gewensde een wanneer die kwessie van die bekostigbaarheid van toenemende sosiale voorsiening in ontwikkelende lande aangespreek word. Die Suid-Afrih:aanse ondervlnding in hierdie verband verskaf verdere getuienis van toenemende kragte, oar tyd, wat groeiende staatsvoorsiening van sosiale sekuriteit (sekerheid) In die hand werk. Die ondervinding voorsien egter oak voorbeelde van hoe hierdie kragte deur spesifleke politieke instellings omvorm kan word en hoe sosiale beleid 1\an agterbly by veranderende omstandighode. Hierdie faktore het aanleiding gegee tot die huidige ongelyke toegang tot sosiale dienste, ongelyke voordele en onvoldoende dekking teen die rlsiko's wat die Suid-Afrikaanse ekonomie inhou. Ten spyte van die tekortkominge van die Suid-Afrik3.anse stelsel van bestaansbeveiliging en die ongelyh:heid daarin gereflehteer, kom dit voor asof fiskale en makro-ekonomiese beperkinge die moontlikhede am die stelsel te omvorm streng beperk: Hierdie beperkinge impliseer, en het aanleiding gegee tot, 'n verlaging van die voordele van die bevoorregte groepe en 'n aanpassing van die aard van voordele, veral in die rigting van goedkoper dienste met steeds hoe opbrengskoerse. Huidige eise en voorsit3ne veranderinge in die sfeer van sosiale beleid. veral ten opsigte van 'n univo3rsele sto::l3o:.l van 3osiale pensioene en spesiale werkskeppingsprogramme, dui egter op die sterkte van die kragte wat to8n8m-:mde "nasionalisering" van sosiale dienste in die hand werk. Hoe die klaarblyklike fish:ale bepalings ta versoen is met die beweerde rasionaliteit van 'n grater rol vir die Suid-Afrikaanse staat in sosiale voorsiening bly 'n vraag. Dit is nodig am die bree perspektief van hierdie studie te evalueer deur in meer detail te kyh: na spesifiek programme en spesifleke oorsah:e van 'n gebrek aan bestaanssekerheid.
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37

Adsuar, García María Dolores. "Catalizadores bifuncionales para la hidrogenación hidrolítica de la celulosa." Doctoral thesis, Universidad de Alicante, 2017. http://hdl.handle.net/10045/69751.

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Анотація:
La presente tesis abarca estudios fundamentales basados en la catálisis heterogénea. El objetivo que se ha planteado en esta tesis doctoral es desarrollar catalizadores heterogéneos bifuncionales activos y selectivos en la reacción de hidrogenación hidrolítica de celulosa. De esta manera se podría contribuir al ambicioso objetivo de reducir las emisiones netas de dióxido de carbono a la atmosfera a través de la utilización de biomasa como fuente de combustibles líquidos. En particular, se han preparado catalizadores de rutenio soportados en materiales carbonosos con centros ácidos para combinar de este modo la actividad hidrogenante del rutenio con la actividad hidrolítica de los centros ácidos. Para ello, se han realizado diversos tratamientos de oxidación a los materiales carbonosos empleados con el fin de mejorar las propiedades ácidas de los soportes. Por otra parte, se ha estudiado el efecto de la adición de ácidos al medio de reacción. Para ello, se han empleado ácido clorhídrico y ácidos silicowolfrámicos (H4SiW12O40 = HPA) en distintas concentraciones. Seguidamente, se preparan catalizadores con heteropoliácidos y nanopartículas de rutenio soportadas en nanotubos de carbono. Tanto de forma conjunta, como independiente. Finalmente, se han estudiado los diversos catalizadores preparados en experimentos en los que se ha empleado el CO2 en estado supercrítico como disolvente.
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38

Greenlee, Alison S. "Development of a melting and directional solidification process for improving the grain structure and electronic properties of a silicon wafer." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/69781.

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Анотація:
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2011.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 57).
A manufacturing process that produces high quality, inexpensive kerfless silicon wafers for photovoltaic cells is highly desirable. The process herein described was developed to melt and directionally solidify fine-grained silicon wafers at accelerated feed rates for improved electronic properties. The proposed process encapsulates a fine grained silicon wafer which is then sandwiched between two substrates with a specialized release layer. This stack is then zonemelted and recrystallized in a novel zone-melting furnace. The innovations herein described pertain to the design of a novel radiation furnace, the substrate selection, and the process parameters required to repeatedly yields planar wafers, with several centimeter sized grains, and a low dislocation density of10⁴4 cm -² . Specifically, the phenomena that govern the thickness profile of the wafer were examined, and process modifications were made to yield a planar wafer with a +/- 15 tm thickness range over 85% of a 6" wafer. Furthermore, a relationship between the thermal characteristics of the zonemelting furnace, the process feed rate, and the relative grain size were derived. This relationship was used to design and characterize a novel, zone-melting radiation furnace that can solidify a silicon wafer with ~10 solidification angle at 60 mm/min. Additionally, preferential nucleation sites that reduce the likelihood of large grains were identified and experimentally minimized by biasing the wafer to cool preferentially from one side. Finally, mechanisms to create dislocations were identified and minimized. This included minimizing the number of stress concentrations in the wafer and reducing the thermal resistance between the wafer and its supporting conductive substrate.
by Alison S. Greenlee.
S.M.
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39

Riley, James Preston. "A paradigm for Kemetic architectural design : the beginnings of a Kemetic architectural design language." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/69741.

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Анотація:
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1996.
Includes bibliographical references (p. 59-60).
Kemetic [Egyptian] architecture is highly recognizable. In particular, there was a distinct monumentality to its religious architecture. As well, familiar design characteristics permeated many of them. These edifices continue to be a source of discussion and debate. Opposing interpretations range in opinion; from traditional and conservative to embedded with scientific and mathematical knowledge. In this thesis, I investigate one facet of the Kemetic architectural tradition. I will first define tradition and architectural tradition. Second, I will identify the main themes. They include the Kemetic architectural continuity; the Kemetic architectural design principle; and, the determinants of the architectural design principle. The themes assist in further understanding underlying components of Kemetic architecture. To demonstrate these points, the Kemetic temple plan is used as a reference point for discussion. In the conclusion, it is my intention to bridge opposing areas of discussion to enhance them and advance the comprehension of Kemetic architecture.
by James Preston Riley, Jr.
M.S.
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40

Rohrbacher, Gary P. (Gary Pickard) 1964. "The architectural details of Alvaro Siza : a chorology." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/69751.

Повний текст джерела
Анотація:
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1998.
Includes bibliographical references (leaves 121-123).
A chorology is an analysis of the relationships between the constituent parts of a system or assemblage. Architecture is not only the result of the connection between a vast set of components and their manifold interactions, it is implanted into still broader, working fields of complex affiliations and relations. Essential to understanding the importance of Alvaro Siza's' buildings is to see his architecture as assemblages comprised of many composite, active subsystems. These assemblages engage still larger systems, dynamic and effects producing. In short, the architecture goes beyond the visual, and generates effects in time and space - engaging animate operations that pre-exist the architecture while inciting multiple new dynamic relations. The architecture must be seen as a machine, testing the line between natural and manmade. Not necessarily organic, but self organized, exhibiting the characteristics of self generating systems, or in other words, life. While a conventional architectural analysis might exhaustively diagram geometric relations, or try to find historical models or precedents to situate the work, this thesis seeks to be critical of the deterministic, historical practice of naming. Instead, opting for a perhaps discursive methodology, which endeavors to understand operative modes that compose the abstract machinic-architectural assemblages of Alvaro Siza. As a beginning to understanding the complex assemblages of Siza, this thesis will specifically examine architectural details, their interrelationships, and affiliations to materials and techniques of construction. Details will be considered as constituent parts of a larger assemblage, and as engaging dynamic criteria (forces, light, program, weather, time, etc.) as a means of conditioning space. By considering the effects which conspire to compose a detail, in conjunction with the effects that are generated, a new understanding of the immeasurable complexity of an architectural assemblage and its' relations to space might be understood. Affording criteria for testing performance, inciting possibilities for new terms of responsiveness in architectural assemblages, and offering new, germane modes of making. this chorology will examine the affiliative assemblages of the Boa Nova Tea House at Leca da Palmeira, Portugal from 1958 and the teachers training college at Setubal, Portugal from 1994. The thesis will carefully examine conditioning agents and effects of detail assemblages, their relationships to operative criteria, other details, and space. instrumental texts include those by Deleuze and Guattari, Fernando Pessoa, and Peter Testa.
by Gary P. Rohrbacher.
M.S.
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41

Roberts, Mark G. (Mark Gerard). "Supply-side analysis of the commercial office market and a replacement cost index." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/69731.

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42

Costello, David Andrew. "Design for automation of the baby teether." Thesis, Massachusetts Institute of Technology, 1989. http://hdl.handle.net/1721.1/69701.

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43

Koh, Cheong Yang (Cheong Yang Henry). "Generalized phononic networks : of length scales, symmetry breaking and (non) locality : "controlling complexity through simplicity"." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/69791.

Повний текст джерела
Анотація:
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2011.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 214-217).
The manipulation and control of phonons is extremely important from both a fundamental scientific and applied technological standpoint, providing applications ranging from sound insulation to heat management. Phononic crystals and metamaterials are artificially structured materials (at certain length scales) that provide promise in controlling the propagation of phonons in solids. However, the vector nature of the phonon makes the development of a governing framework with which to guide the design of these phononic metamaterials complicated and no coherent framework exists for the design of phononic structures. In this thesis, we utilize a combination of global symmetry principles, adopted from group theory and the theory of representations, together with conservation principles and broken symmetry concepts to formulate our generalized design framework. This framework allows us to exactly treat the vector nature of phonons and control their propagation, unifying the design of phononic crystals, metamaterials, waveguides and numerous other structures, both infinite and finite. In particular, utilizing only this general framework which we develop, we are able to explain the choice of a particular physical topography for a desired phononic propagation behavior in a coherent fashion. In addition, we show how we may explicitly control the dispersion relations of a phononic metamaterial in order to obtain a desired final band structure. Some of our demonstrations include a new polychromatic phononic metamaterial which possesses multiple complete in-plane spectral gaps totaling over 100% in normalized gap size to a phononic metamaterial which exhibits a single complete in-plane spectral gap of 102% and a complete spectral gap of 88%, both significant advancements over the state of the art. This thesis also removes the artificial distinction between the phononic crystal and metamaterial classifications by unifying their behavior within the same generalized framework. As a result, we show that only a few governing principles are required to design the complex band dispersion relations of phononic metamaterials. The generality of our framework allows extension to other vector and scalar waves, such as photonic, plasmonic and magnonic structures and provides a promising route forward to the development of integrated structured material platforms that allow for the rational manipulation and interactions of phonons with other waves, such as phonons and spin waves.
by Cheong Yang (Henry) Koh.
Ph.D.
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44

Guo, Huili. "A study of mammalian microRNA-mediated repression of gene expression by ribosome profiling." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/69771.

Повний текст джерела
Анотація:
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Biology, 2011.
Cataloged from PDF version of thesis. Vita.
Includes bibliographical references.
All cells in a multicellular organism carry the same genes, yet these same genes direct the differentiation of many different cell types. This is facilitated by differential gene expression, the control of which can be exerted at the transcriptional, as well as post-transcriptional, level. MicroRNAs (miRNAs) are -22- nucleotide small RNAs that mediate post-transcriptional regulation of gene expression by base pairing to their target mRNAs to direct repression. In animals, this repression is usually mediated through translational repression and/or mRNA destabilization. In studies that investigate miRNA-mediated repression with reporter constructs or individual endogenous genes, translational repression and mRNA destabilization have been observed to contribute variably to the overall level of repression. This led to the question of whether the same was true for endogenous targets at a genome-wide level. While changes in mRNA levels can be easily captured by microarray measurements, it is harder to measure translational repression on a genome-wide scale. To address this gap, we used ribosome profiling to measure effects on protein production and compared these to simultaneously measured effects on mRNA levels. The latter were also quantified by a deep-sequencing approach (mRNA-Seq). This enabled us to obtain a snapshot of changes in translational efficiency at the genome-wide level. For both ectopic and endogenous miRNA regulatory interactions, we observed that lowered mRNA levels account for most (>84%) of the decreased protein production. These results show that changes in mRNA levels closely reflect the impact of miRNAs on gene expression and indicate that destabilization of target mRNAs is the predominant reason for reduced protein output. The slight reduction in translational efficiency is likely mediated by an inhibition of translation initiation. For studying miRNA repression in an endogenous system, we had initially used in vitro differentiated neutrophils from mir-223 knockout mice and compared these to cells from wild-type mice. Because neutrophils have a shorter lifespan than most differentiated cell types, we selected another endogenous system, antigen-stimulated B cells from mir-155 knockout mice, and similarly compared these to cells from wild-type mice. In addition to mRNA-Seq and ribosome profiling, we made parallel proteomics measurements. Our results show that miR- 155 in antigen-stimulated B cells primarily mediates mRNAlevel changes, though the contribution from changes in translational efficiency was larger than previously observed. In addition, we observed widespread translation of upstream open reading frames initiated from canonical and non-canonical start codons. These upstream open reading frames are also translationally repressed by miR-155.
by Huili Guo.
Ph.D.
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45

Saheba, Asheshh (Asheshh Mohit) 1972. "Variable volume architecture : expanding the boundary." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/69761.

Повний текст джерела
Анотація:
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2001.
Includes bibliographical references (p. [88]-89).
Research into the creation of a Variable Volume Architecture is explored through a series of proposals and projects. An argument is established to develop the means and methods of achieving an architecture of transformation. The basis for developing such a stance is substantiated and clarified with the act of probing into constructs of various scales. The design and manufacturing of a full scale prototype is explored to bring bearing on the physical resolution of the proposal. The device is an acknowledgment of potential applications and uses. The material, spatial, and structural nature of the propositions are articulated and examined throughout the investigation. The morphology of the concepts presented is derived to bring clarity to issues towards an endeavor for creating a responsive architectural landscape.
by Asheshh Saheba.
S.M.
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46

Roberts, Christine L. "Conflict and cooperation in watershed management : case study of metropolitan Boston's water supplies." Thesis, Massachusetts Institute of Technology, 1990. http://hdl.handle.net/1721.1/69711.

Повний текст джерела
Анотація:
Thesis (M.C.P.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 1990.
Title as it appears in the M.I.T. Graduate List, June 1990: Cooperation and conflict in watershed management.
Includes bibliographical references (leaves 144-151).
by Christine L. Roberts.
M.C.P.
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47

Oliveira, Nilza Duarte Aleixo de. "Desenvolvimento sustentável, inovação, tecnologia social e empreendedorismo coletivo em relacionamentos intercooperativos : Sistema CREDITAG e cooperativas de produção agrícola de Rondônia." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2013. http://hdl.handle.net/10183/69721.

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Анотація:
As iniciativas econômicas locais de caráter coletivo representam para os segmentos sociais de baixa renda, uma importante opção estratégica, capaz de transformar ou modificar determinada realidade, um caminho viável e promotor de desenvolvimento econômico e social. O surgimento desses empreendimentos tem como principal estímulo, a emergência de combater o desemprego, baixa renda e as privações decorrentes. O CREDITAG - Sistema de Cooperativas de Crédito Rural da Agricultura Familiar e Economia Solidária, no Estado de Rondônia é uma dessas iniciativas, formada por agricultores familiares, para que possam ter acesso a crédito, financiamentos dos meios de produção e insumos, já que, nem o Estado e nem as empresas, oferecem soluções às suas necessidades, pelo menos no médio prazo. E, como estratégia de fortalecimento, as cooperativas de crédito do Sistema CREDITAG em Rondônia, incorporam em seu quadro de cooperados, quatro cooperativas de produção, com o propósito de fortalecer os dois ramos cooperativistas, por meio da intercooperação, o que pode favorecer os cooperados, no tocante a tecnologia, novos produtos e serviços, redução de custos, mais canais de comercialização, dentre outros. Essa relação de intercooperação constituiu-se no objeto de análise da presente tese, cuja proposição central exposta é que para a perspectiva de Desenvolvimento Sustentável, os benefícios gerados por esses modelos organizacionais, devem superar o assistencialismo e promover a inclusão social e produtiva, fortalecendo os indivíduos para a autonomia. Neste sentido, a questão de pesquisa apresentada foi a seguinte: a relação de intercooperação, entre sistema CREDITAG e suas associadas, cooperativas de produção agrícola, está promovendo, de forma sustentável, empreendedorismo coletivo, inovação social e tecnologia social? A partir da definição da questão de pesquisa, definiu-se o objetivo geral, que consiste em: elaborar um framework que permita verificar a existência de desenvolvimento sustentável, empreendedorismo coletivo, inovação social e tecnologias sociais, na relação de intercooperação entre sistema CREDITAG e suas associadas, cooperativas de produção agrícola, de Rondônia. Trata-se de um estudo exploratório-descritivo-explicativo, utilizando-se o método de estudo de campo. A questão de pesquisa e os objetivos foram abordados, sob um enfoque qualitativo e quantitativo. A coleta de dados, na etapa qualitativa deu-se por meio de entrevista informal e em profundidade e, na etapa quantitativa, procedeu-se a aplicação de questionários. Participaram da pesquisa: 95 cooperados, 6 parceiros e 11 gestores das cooperativas de crédito e de produção e do Sistema CREDITAG/base/RO. Os resultados demostram que a relação de intercooperação, se faz acompanhar de boas médias de concordância para a presença do empreendedorismo, tecnologias sociais e inovação, com destaque para a inovação social. A relação de intercooperação pode ser tratada como uma inovação social que contribui para melhoria da qualidade de vida dos produtores, para o fortalecimento das organizações integrantes e para o Desenvolvimento Sustentável. Apesar das fragilidades identificadas, limites históricos e estrutrais, a relação de intercooperação apresenta potencial para proporcionar a inclusão social, produtiva e bancária, contribuir para o equacionamento de problemas de ordem econômica, financeira e social dos cooperados, geração de empregos e renda e para o desenvolvimento das comunidades locais.
The local economic initiatives of collective character are to represent the low-income segments of society, an important strategic option that can transform or modify certain realities, it´s a viable path and promoter of economic and social development. The emergence of these enterprises has as its main stimulus, the emergency to combat unemployment, low income and deprivation arising. The CREDITAG – The System of Rural Credit Cooperatives of the Agriculture Family and Economic Solidarity in the State of Rondônia, is one such initiative, formed by Agriculture families, so they can have access to credit, financing by means of production and inputs, since neither the state nor the companies offer solutions to their needs, at least in the medium term. And, as a strategy for strengthening the cooperative credit system CREDITAG in Rondônia, they incorporate in its framework for cooperative members, four production cooperatives, in order to strengthen the two cooperative branches, through inter-cooperation, which can promote the cooperative with regard to technology, new products and services, cost savings, more marketing channels, among others. This intercooperation relationship constituted the object of analysis of this thesis, whose central proposition is exposed to the prospect of sustainable development; the benefits generated by these organizational models must overcome welfare and promote social inclusion and production, strengthening individuals for independence. In this regard, the research question presented was as follows: Is the intercooperation relationship between the CREDITAG system and its associated agricultural cooperatives promoting a sustainable, collective entrepreneurship, social innovation and social technology? From the definition of the research question, we defined the overall goal, which is: to develop a framework to verify the existence of sustainable development, collective entrepreneurship, social innovation and social technologies, the intercooperation relationship between the CREDITAG system and its agricultural cooperative associates, Rondônia. This is an exploratory, descriptive, explicative study, using the method of field study. The research question and objectives were covered under a qualitative and quantitative approach. The data collection in the qualitative stage took place through an in depth informal interview, and in the quantitative stage, it proceeded with questionnaires. The participants were: 95 members, 6 partners and 11 managers of the credit unions and Production System CREDITAG / base / RO. The results show that the ratio of inter-cooperation is accompanied by good means of agreement for the presence of entrepreneurship, technology and social innovation, highlighting social innovation. The intercooperation relationship can be treated as a social innovation that contributes to improving the quality of life of the farmers, to strengthen organizations and members for Sustainable Development. Despite the weaknesses identified, structure and historical boundaries, the inter-cooperation relationship has potential to provide social inclusion, production and banking contribute to the solving of problems of the economic, financial and social members, generating jobs and income for the development of local communities.
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48

Botton, Mariana Rodrigues. "Farmacogenética da varfarina : proposta de um algoritmo para a predição de dose." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2010. http://hdl.handle.net/10183/69701.

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Анотація:
A varfarina é um medicamento da classe dos anticoagulantes orais cumarínicos muito utilizada na profilaxia de doenças tromboembólicas. Existe uma grande variação interindividual na resposta aos cumarínicos, uma vez que a farmacocinética e a farmacodinâmica do medicamento variam de acordo com fatores ambientais e genéticos. As enzimas CYP2C9, responsável pela maior parte da metabolização do fármaco, e VKORC1, alvo dos cumarínicos, estão diretamente envolvidas na farmacocinética e farmacodinâmica da varfarina, respectivamente. A enzima CYP4F2, envolvida na metabolização de vitamina K, atua de forma indireta na farmacodinâmica do medicamento. O fator II é um fator de coagulação dependente de carboxilação, sendo sua funcionalidade dependente da atuação da varfarina. Polimorfismos nestes genes estão relacionados com variação na resposta ao medicamento. Neste trabalho foi investigada a influência dos polimorfismos CYP2C9*2 e CYP2C9*3 no gene CYP2C9, -1639G>A, 1173C>T e 3730G>A no gene VKORC1, 1347C>T no gene CYP4F2 e 494C>T no gene F2 na dose/resposta de varfarina de forma independente, assim como foi elaborado um modelo incluindo fatores genéticos e não-genéticos capazes de predizer a dose de varfarina necessária a cada paciente. Para a realização das análises foram estudados 279 pacientes usuários de varfarina provenientes do Hospital de Clínicas de Porto Alegre com ascendência européia. Todos os SNPs dos genes CYP2C9, VKORC1, CYP4F2 e F2 foram identificados pelo sistema TaqMan de discriminação alélica através de PCR em tempo real. Os alelos CYP2C9*2 (P<0,001) e CYP2C9*3 (P<0,001) do gene CYP2C9, -1639A (P<0,001) e 1173T (P<0,001) do gene VKORC1 e 494T do gene F2 são responsáveis pela necessidade de uma dose menor do anticoagulante. Em contrapartida, os alelos 1347T do gene CYP4F2 e 3730A (P<0,001) do gene VKORC1 são responsáveis pela necessidade de uma dose maior de varfarina. Os valores de P referentes aos polimorfismos nos genes CYP4F2 e F2 referem-se à análise multivariada, após controlar por confundidores, pois na análise univariada estes polimorfismos não apresentaram associação com a dose de varfarina. A partir destes polimorfismos e de algumas variáveis clínicas foi elaborado um algoritmo que consegue explicar 63,3% da variação de dose de varfarina. Este algoritmo incluiu os seguintes fatores: peso, idade, uso de anlodipino, amiodarona, carbamazepina, -bloqueadores, diuréticos de alça e polimorfismos nos genes CYP2C9, VKORC1, CYP4F2 e F2. A média da diferença absoluta entre a dose predita e a dose observada foi de 6,9 mg/semana e a correlação entre as doses predita e observada foi rs=0,77. O modelo sugerido é um dos que apresenta maior coeficiente de determinação entre os descritos na literatura, porém, para que seja possível um futuro uso clínico é necessário que seja validado em uma amostra independente. Mais estudos também são necessários para que se consiga determinar os outros fatores que expliquem os 40% da variação de dose não explicada até o momento.
Warfarin is a drug from coumarin anticoagulant class widely used for thromboembolic disease prophylaxis. There is a wide interindividual variation in response to coumarins, since the pharmacokinetics and pharmacodynamics of this drug vary with environmental and genetic factors. The CYP2C9 enzyme, responsible for drug metabolism, and VKORC1, the coumarin target, are directly involved in the pharmacokinetics and pharmacodynamics of warfarin, respectively. The CYP4F2 enzyme, involved in the metabolism of vitamin K, acts indirectly on the pharmacodynamics of the drug. Factor II is a coagulation factor dependent on carboxylation, and its function depends on warfarin action. Polymorphisms in these genes are related to drug variation response. In this study we investigated the influence of the CYP2C9*2 and CYP2C9*3 polymorphisms in CYP2C9 gene, -1639G>A, 1173C>T and 3730G>A in the VKORC1 gene, 1347C>T in the CYP4F2 gene and 494C>T in the F2 gene with warfarin dose/response independently. In addition, a model including genetic and nongenetic factors able to predict warfarin dose needed for each patient was developed. The analysis was performed with 279 patients of European ancestry from the Hospital de Clínicas de Porto Alegre taking warfarin. All SNPs from CYP2C9, VKORC1, CYP4F2 and F2 genes were identified by TaqMan system of allelic discrimination by real-time PCR. The CYP2C9*2 (P <0.001) and CYP2C9*3 (P <0.001) polymorphisms in the CYP2C9 gene, -1639G>A (P <0.001) and 1173C>T (P <0.001) in VKORC1 gene and 494C>T in F2 gene are responsible for lower doses of anticoagulant. In contrast, the SNPs 1347C>T in the CYP4F2 gene and 3730G>A (P <0.001) in VKORC1 gene are responsible for higher doses of warfarin. P values regarding CYP4F2 and F2 polymorphisms refer to multivariate analysis after controlling for confounders, since in the univariate analysis these polymorphisms were not associated with warfarin dose. An algorithm considering these polymorphisms and some clinical variables was developed that explains 63.3% of the variation in warfarin dose. This algorithm included the following factors: body weight, age, use of anlodipine, amiodarone, carbamazepine, -blockers, loop diuretics and polymorphisms in CYP2C9, VKORC1, CYP4F2 and F2 genes. The average absolute difference between the predicted dose and observed dose was 6.9 mg/week and the correlation between the observed and predicted doses was rs=0.77. The model suggested is one with the higher coefficient of determination among those described in the literature, however, for a possible future clinical use it must be validated in an independent sample. More studies are warranted to find other factors that explain the 40% dose variation not explained so far.
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49

Cardin, Léo. "La charge de travail perçue des cadres du réseau collégial québécois." Master's thesis, Université Laval, 2021. http://hdl.handle.net/20.500.11794/69701.

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Анотація:
Depuis le début des années 1990, le réseau collégial québécois a subi plusieurs changements de nature sociale et politique. À titre illustratif, nommons notamment la transformation de la population étudiante, l'introduction des TIC, l'implantation de la réforme Robillard en 1993, la ratification de la Loi sur l'administration publique en 2000, etc. Ces changements n'ont pas épargné le personnel d'encadrement de ce réseau. Dans ce contexte, nous nous sommes intéressés à la charge de travail perçue des gestionnaires des 48 établissements collégiaux répartis à travers le territoire québécois. Plus précisément, nous cherchons à connaître les composantes du travail des cadres qui augmentent ou réduisent leur charge de travail perçue. Suite à la réalisation d'une dizaine d'entrevues exploratoires et à l'administration d'un questionnaire par voie électronique à l'ensemble des gestionnaires de cégep, nous arrivons à la conclusion que quatre principaux éléments semblent augmenter la charge de travail des cadres. Il s'agit de la hausse des demandes de reddition de compte, l'utilisation des nouvelles technologies, l'urgence de l'exécution des tâches et la hausse du rythme de travail ainsi que l'augmentation du niveau de responsabilité.
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50

Zarié, Alexandre. "Les écoles polyvalentes au Québec : historique, finalités éducatives, architecture scolaire et usages pédagogiques." Master's thesis, Université Laval, 2021. http://hdl.handle.net/20.500.11794/69711.

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Анотація:
Les pratiques enseignantes actuelles s'inscrivent souvent dans des cadres spatiaux définis par des générations précédentes. Au secondaire, les situations d'enseignement-apprentissage se déroulent régulièrement au sein d'institutions anciennement nommées polyvalentes et établies durant les décennies 1960/70. Ce mémoire s'inscrit dans le cadre du projet Schola.ca portant sur les caractéristiques du parc scolaire primaire et secondaire québécois afin d'offrir des outils pour sa rénovation et son optimisation. Dans ce contexte, notre recherche étudie les espaces scolaires au secondaire et les usages des enseignants au sein de ces lieux. Pour ce faire, dans un premier temps, divers documents officiels, plans architecturaux et numéros de revues d'architecture ont été analysés afin de comprendre comment les facteurs socioéconomiques, politiques, architecturaux et surtout éducatifs ont influencé la conception et la définition de ces écoles. Dans un second temps, une entrevue avec deux enseignants a été menée afin de documenter les pratiques spatiales au sein d'une école secondaire de la région de Québec. L'analyse de ce corpus a été faite en se basant sur diverses théories provenant de sociologues des espaces et de l'éducation. Celles permettent une compréhension accrue des polyvalentes définies à la suite du rapport Parent (les polyvalentes) et des usages actuels des enseignants. À travers cette étude de cas, cette recherche a pour but d'éclairer le projet Schola.ca sur la façon dont les enseignants s'approprient les espaces ou les adaptent en fonction de leurs besoins.
Today's teaching practices are often held in space settings defined by past generations. Teaching-learning situations in high schools, often take place in institutions formerly known as comprehensive schools built during the 1960s/'70s. This M.A. thesis is linked to the Schola.ca project which studies the characteristics of Quebec's elementary and high schools, in order to provide tools for their renovation and optimization. In this context, our research studies the school spaces in high schools, as well as teacher's practices within them. Numerous official documents, architectural plans and journals were analyzed, in order to understand how socio-economic, political, architectural and mainly educational factors have influenced the design and definition of these schools. Moreover, a discussion with two teachers from a high school in the City of Quebec area has allowed a better understanding of how teachers adapt the scholastic spaces to fit their needs. Thanks to the various theoretical tools developed by space sociologists and sociologists of education, we were able to better understand the links between the design of school spaces following the Parent Report (comprehensive schools) and the current use of these same spaces by teachers. Focusing on space practices through a case study in a high school located in the City of Quebec area, our research aims to inform the Schola.ca project on how teachers take over space or adapt it to their needs.
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