Дисертації з теми "Objective investigation"
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1
Maashi, Mashael. "An investigation of multi-objective hyper-heuristics for multi-objective optimisation." Thesis, University of Nottingham, 2014. http://eprints.nottingham.ac.uk/14171/.
Повний текст джерелаАнотація:
In this thesis, we investigate and develop a number of online learning selection choice function based hyper-heuristic methodologies that attempt to solve multi-objective unconstrained optimisation problems. For the first time, we introduce an online learning selection choice function based hyperheuristic framework for multi-objective optimisation. Our multi-objective hyper-heuristic controls and combines the strengths of three well-known multi-objective evolutionary algorithms (NSGAII, SPEA2, and MOGA), which are utilised as the low level heuristics. A choice function selection heuristic acts as a high level strategy which adaptively ranks the performance of those low-level heuristics according to feedback received during the search process, deciding which one to call at each decision point. Four performance measurements are integrated into a ranking scheme which acts as a feedback learning mechanism to provide knowledge of the problem domain to the high level strategy. To the best of our knowledge, for the first time, this thesis investigates the influence of the move acceptance component of selection hyper-heuristics for multi-objective optimisation. Three multi-objective choice function based hyper-heuristics, combined with different move acceptance strategies including All-Moves as a deterministic move acceptance and the Great Deluge Algorithm (GDA) and Late Acceptance (LA) as a nondeterministic move acceptance function. GDA and LA require a change in the value of a single objective at each step and so a well-known hypervolume metric, referred to as D metric, is proposed for their applicability to the multi-objective optimisation problems. D metric is used as a way of comparing two non-dominated sets with respect to the objective space. The performance of the proposed multi-objective selection choice function based hyper-heuristics is evaluated on the Walking Fish Group (WFG) test suite which is a common benchmark for multi-objective optimisation. Additionally, the proposed approaches are applied to the vehicle crashworthiness design problem, in order to test its effectiveness on a realworld multi-objective problem. The results of both benchmark test problems demonstrate the capability and potential of the multi-objective hyper-heuristic approaches in solving continuous multi-objective optimisation problems. The multi-objective choice function Great Deluge Hyper-Heuristic (HHMO_CF_GDA) turns out to be the best choice for solving these types of problems.
2
Davies, Ceri Wyn. "A theoretical and experimental investigation into objective olfactometry." Thesis, University of the West of England, Bristol, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387407.
Повний текст джерела
3
Pathi, Soumya Sundar. "Investigation of genetic algorithm design representation for multi-objective truss optimization." Texas A&M University, 2006. http://hdl.handle.net/1969.1/4430.
Повний текст джерелаАнотація:
The objective of this research is to develop a flexible design grammar and
genetic algorithm representation to be used in a multi-objective optimization method to
design efficient steel roof trusses given space dimensions and loading requirements by
the user. The goal of implementing the method as a multi-objective problem is to obtain
a set of near-optimal trusses for the defined unstructured problem domain, not just a
single near-optimal design. The method developed was required to support the
exploration of a broad range of conceptual designs before making design decisions.
Therefore, a method was developed that could define numerous design variables, support
techniques to locate global or near-global optimal designs, and improve the efficiency of
the computational procedures implemented. This research effort was motivated by the
need to consider structural designs that may be beyond the established conventions of
designers in the search for cost-efficient, structurally-sound designs.
An effective design grammar that is capable of generating stable trusses is
defined in this research. The design grammar supports the optimization of member size,
in addition to truss geometry and topology. Multi-objective genetic algorithms were used
to evolve sets of Pareto-optimal trusses that had varying topology, geometry, and
member sizes. The Pareto-optimal curves provided design engineers with a range of
near-optimal design alternatives that showed the tradeoffs that occur in meeting the
stated objectives. Designers can select their final design from this set based on their own
individual weighting of the design objectives. Trials are performed using a multiobjective
genetic algorithm that works with the design grammar to evolve trusses for different span lengths. In addition to evaluate the performance of the developed
optimization method further, trials were performed on a benchmark truss problem
domain and the results obtained were compared with results obtained by other
researchers.
The results of the performance evaluation trials for the proposed method, in
which the sizing, shape and topology were simultaneously performed, indicated that the
method was effective in evolving a variety of truss topologies compared to previous
published results, which evolved from a ground structure. The diverse topologies,
however, were obtained over several trials instead of being found in a Pareto-optimal set
found by a single trial. In addition, the proposed method was not able to locally
optimize the member section sizes. Additional trials were performed to determine the
benefit of applying local optimization to the member section sizes for a given truss
topology or geometry provided by the method. The results indicate that significant
weight reduction could be achieved by performing local optimization to the truss designs
obtained by the proposed multi-objective optimization method.
4
Kerrigan, Judith. "An investigation into the engineering of fabric properties using fabric objective measurement techniques." Thesis, Nottingham Trent University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.393745.
Повний текст джерелаАнотація:
Objective measurement techniques have been used since the 1930's to provide a more accurate method of gauging fabric quality than subjective hand evaluations. In addition to predicting subjective hand preferences, they also provide data on fabric development and ease of garment manufacture. The main techniques researched are the Kawabata Evaluation System and the Fabric Assurance by Simple Testing. The KES has been used to evaluate suiting, women's dresses, knitted fabrics and nonwoven fabrics. Research with the FAST has been limited to mainly suiting with some shirting. This has left a large area of work to be explored; whether the FAST can be used to assess fabrics for a wider range of end-uses. In this thesis, the investigation focuses on women's dress fabrics, specifically weight reduced polyester fabrics. The FAST system was modified in order to accurately differentiate between these fabrics. The Cusick drape tester was also used and further investigations focussed on other methods of testing drape, including the Aldrich method and one developed by the author. Although early indications were that this new test was repeatable, reproducible and correlated well with the Cusick method, it required more engineering work than was possible in the scope of this thesis and therefore was not used for the empirical work. The KES equipment for tensile and shear was also used and comparison made between the results of previous studies and with results found from the FAST. Statistical analysis was used throughout to establish both the effect of the weight reduction process on the fabric and its relationship to the problems of ease of manufacture, distortion of garment measurements and garment appearance. The modifications made to the FAST procedure and apparatus proved valid during the analysis. The effect of the weight reduction process was to soften the fabric, reducing the drape coefficient and bending and shear rigidity results and increasing the weft extension results. The appearance data could not be statistically analysed but it seemed that for the garment silhouette chosen, low or no weight reduction was required. Equations were established that predicted ease of manufacture and correlation factors were found between actual and predicted grades ranging from 0.71- 0.87. Interestingly, one of the most powerful combinations was the basis data of weight and number of warp ends. High correlation between predicted and actual grades was also found for the distortion problem (0.86).
5
López, De La Cova Trujillo Miguel Angel, and Niklas Bertilsson. "Investigation of the workforce effect of an assembly line using multi-objective optimization." Thesis, Högskolan i Skövde, Institutionen för ingenjörsvetenskap, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-13134.
Повний текст джерелаАнотація:
ABSTRACT The aim of industrial production changed from mass production at the beginning of the 20th century. Today, production flexibility determines manufacturing companies' course of action. In this sense, Volvo Group Trucks Operations is interested in meeting customer demand in their assembly lines by adjusting manpower. Thus, this investigation attempts to analyze the effect of manning on the main final assembly line for thirteen-liter heavy-duty diesel engines at Volvo Group Trucks Operations in Skövde by means of discrete-event simulation. This project presents a simulation model that simulates the assembly line. With the purpose of building the model data were required. One the one hand, qualitative data were collected to improve the knowledge in the fields related to the project topic, as well as to solve the lack of information in certain points of the project. On the other hand, simulation model programming requires quantitative data. Once the model was completed, simulation results were obtained through simulation-based optimization. This optimization process tested 50,000 different workforce scenarios to find the most efficient solutions for three different sequences. Among all results, the most interesting one for Volvo is the one which render 80% of today’s throughput with the minimum number of workers. Consequently, as a case study, a bottleneck analysis and worker performance analysis was performed for this scenario. Finally, a flexible and fully functional model that delivers the desired results was developed. These results provide a comparison among different manning scenarios considering throughput as main measurement of the main final assembly line performance. After analyzing the results, system output behavior was revealed. This behavior allows predicting optimal system output for a given number of operators.
6
Munroe, George. "Investigation of objective assessment of human sperm motility : laser light scattering and computer techniques." Thesis, Queen's University Belfast, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317134.
Повний текст джерела
7
Watkins, Gregory Douglas. "Speech Intelligibility Prediction for Cochlear Implant Recipients: An investigation of the Output Signal to Noise Ratio." Thesis, University of Sydney, 2020. https://hdl.handle.net/2123/22909.
Повний текст джерелаАнотація:
Cochlear implants (CI) can achieve excellent hearing outcomes for people with severe or profound hearing loss. However, outcomes vary significantly, and hearing in noise is challenging. Evaluation of new sound processing ideas with recipient testing is a lengthy process. A metric which reliably predicted CI speech intelligibility would allow more sound processing ideas and parameter sets to be evaluated. Prediction for normal hearing people has been extensively investigated but CIs have received little attention. In this thesis, it was hypothesised that an extended Output Signal to Noise Ratio (OSNR) metric would be a reliable predictor of individual CI speech intelligibility. A series of retrospective CI experiments found i. OSNR was sensitive to changes in a range of test parameters, including Input Signal to Noise Ratio (ISNR), presentation level, noise type, and processing algorithms. ii. OSNR predicted mean speech scores for a group of recipients at least as accurately as other tested metrics. Being calculated at the sound processor output OSNR predicted scores in scenarios where other metrics could not. iii. A novel method, combining OSNR and test scores from a reference condition, predicted psychometric functions for individual CI recipients relatively accurately in many other conditions. Small differences in performance between test and reference conditions were accurately predicted. OSNR was not accurate in the presence of aggressive spectral masking. The feasibility of combining OSNR and Output Speech Power as an accurate predictor in this scenario was demonstrated. The author is not aware of any published works which predict psychometric functions for individual CI recipients listening to speech processed by novel algorithms, using scores from a separate, reference condition. Overall, there was considerable support for the hypothesis that OSNR was an accurate predictor. OSNR shows promise as a metric with research and clinical applications.
8
Jin, Lei. "The impact of co-operation policies on participation in online learning objective exchange a preliminary investigation /." Waterloo, Ont. : University of Waterloo, [Dept. of Management Sciences], 2002. http://etd.uwaterloo.ca/etd/ljin2002.pdf.
Повний текст джерелаАнотація:
Thesis (M.A.Sc.) - University of Waterloo, 2002."A thesis presented to the University of Waterloo in fulfilment of the thesis requirement for the degree of Master of Applied Science in Management Sciences". Includes bibliographical references.
9
Fischer, Robert. "Investigation into sustainable energy systems in Nordic municipalities." Licentiate thesis, Luleå tekniska universitet, Energivetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-78091.
Повний текст джерелаАнотація:
Municipal energy systems in Nordic environments face multiple challenges: the cold climate, large-scale industries, a high share of electric heating and long distances drive energy consumption. While actions on the demand side minimize energy use, decarbonization efforts in mining, industries, the heating and the transport sector can increase the consumption of electricity and biofuels. Continued growth of intermittent wind and solar power increases supply, but the planned phase out of Swedish nuclear power will pose challenges to the reliability of the electricity system in the Nordic countries. Bottlenecks in the transmission and distribution grids may restrict a potential growth of electricity use in urban areas, limit new intermittent supply, peak electricity import and export. Environmental concerns may limit growth of biomass use. Local authorities are committed in contributing to national goals on mitigating climate change, while considering their own objectives for economic development, increased energy self-sufficiency and affordable energy costs. Given these circumstances, this thesis investigates existing technical and economic potentials of renewable energy (RE) resources in the Nordic countries with a focus on the northern counties of Finland, Norway and Sweden. The research further aims to provide sets of optimal solutions for sustainable Nordic municipal energy systems, where the interaction between major energy sectors are studied, considering multiple objectives of minimizing annual energy system costs and reducing carbon emissions as well as analyzing impacts on peak electricity import and export. This research formulates an integrated municipal energy system as a multi-objective optimization problem (MOOP), which is solved by interfacing the energy system simulation tool EnergyPLAN with a multi-objective evolutionary algorithm (MOEA) implemented in Matlab. In a first step, the integration or coupling of electricity and heating sectors is studied, and in a second step, the study inquires the impacts of an increasingly decarbonized transport sector on the energy system. Sensitivity analysis on key economic parameters and on different grid emission factors is performed. Piteå (Norrbotten County, Sweden) is a typical Nordic municipality, which serves as a case study for this research. The research concludes that significant techno-economic potentials exist for the investigated resources. Optimization results show that CO2 emissions of a Nordic municipal energy system can be reduced by about 60% without a considerable increase in total energy system costs and that peak electricity import can be reduced by up to 38%. The outlook onto 2030 shows that the transport sector could be composed of high electrification shares and biofuels. Technology choices for optimal solutions are highly sensitive to electricity prices, discount rates and grid emission factors. The inquiries of this research provide important insights about carbon mitigation strategies for integrated energy sectors within a perspective on Nordic municipalities. Future work will refine the transport model, develop and apply a framework for multi-criteria decision analysis (MCDA) enabling local decision makers to determine a technically and economically sound pathway based on the optimal alternatives provided, and analyze the existing policy framework affecting energy planning of local authorities.Kommunala energisystem i nordiska miljöer möter flera utmaningar: det kalla klimatet, storskaliga industrier, en stor andel elvärme och långa distanser driver energiförbrukningen. Medan åtgärder vidtas på efterfrågesidan för att minimera energianvändningen, kan utsläppsminskande åtgärder inom gruvdrift, industrier, uppvärmningen och transportsektorn öka förbrukningen av el och biobränslen. Fortsatt tillväxt av intermittent vind- och solkraft ökar elproduktion, men den planerade avvecklingen av svensk kärnkraft kommer att utmana tillförlitligheten i elsystemet i de nordiska länderna. Flaskhalsar i överförings- och distributionsnäten kan begränsa en potentiell tillväxt av elanvändningen i stadsområden, begränsa ny intermittent utbud, och påverka elutbyte mellan länderna. Miljöhänsyn kan begränsa ökad användning av biomassa. Lokala myndigheter är engagerade i att bidra till nationella klimatmål, samtidigt som de följer sina egna mål för ekonomisk utveckling, ökad självförsörjning av energi och överkomliga energikostnader. Mot bakgrund av dessa omständigheter undersöker denna avhandling befintliga tekniska och ekonomiska potentialer för förnybar energi i Norden med fokus på de nordliga länen i Finland, Norge och Sverige. Forskningen syftar vidare till att utveckla optimala lösningar för hållbara nordiska kommunala energisystem, där samspelet mellan stora energisektorer studeras, med tanke på att minimera årliga energisystemkostnader och samtidigt minska koldioxidutsläppen samt analysera påverkan på elimport till och export från kommunen. Denna forskning formulerar ett integrerad kommunalt energisystem som multimåloptimeringsproblem (multi-objective optimisation problem - MOOP), som löses genom att kombinera simuleringsverktyget EnergyPLAN med en evolutionär algoritm implementerad i Matlab. I ett första steg studeras kopplingen av el- och värmesektorerna, och i ett andra steg effekterna av en integrerad och alltmer förnybar transportsektor på energisystemet. Känslighetsanalys på viktiga ekonomiska parametrar och på olika utsläppsfaktorer utförs. Piteå (Norrbottens län, Sverige) är en typisk nordisk kommun som fungerar som en fallstudie för detta arbete. Forskningens slutsatser innebär att det finns betydande teknisk-ekonomiska potentialer för de undersökta förnybara resurserna. Optimeringsresultaten visar att koldioxidutsläppen från ett nordiskt kommunalt energisystem kan minskas med cirka 60% utan en avsevärd ökning av de totala energisystemkostnaderna och att den högsta elimporten kan minskas med upp till 38%. Resultat för år 2030 visar att transportsektorn kan ha en mycket hög elektrifieringsgrad och samtidigt används biobränslen i tunga fordon. Optimala lösningar är mycket känsliga för elpriser, räntor och utsläppsfaktorer. Detta arbete ger viktiga insikter om strategier för koldioxidminskning för integrerade energisektorer i ett perspektiv på nordiska kommuner. Min framtida forskning kommer att förfina transportmodellen, utveckla och tillämpa ett ramverk för beslutsanalys med flera kriterier (multi-criteria decision analysis - MCDA) som ska stödja lokala myndigheter att fastställa tekniskt och ekonomiskt hållbara lösningar i deras energiplanering.
10
Watson, John Lawrence, and not supplied. "An investigation into the identification of objective parameters correlating with the subjective functional performance of critical listening rooms." RMIT University. Applied Sciences, 2006. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20080218.092220.
Повний текст джерелаАнотація:
The link to subjective parameters and objective parameters in the field of room acoustics has been the source of much research. This thesis surveys some of the available objective room acoustical analysis methods, quantify their advantages and disadvantages with respect to the measurement of acoustical qualities of professionally operated critical listing rooms, and implements these methods in a range of critical listening rooms. In conjunction with the objective room analysis, a subjective component of research was also performed. A series of anechoically recorded standard instrument sounds were presented to professional listeners in their critical listening spaces with the listeners asked to alter the sounds to taste: to
11
Basoudan, Nasreen S. "A neuropsychological investigation of non-clinical anxiety levels and information processing speed in ageing, subjective and objective cognitive functions." Thesis, Swansea University, 2018. https://cronfa.swan.ac.uk/Record/cronfa48729.
Повний текст джерелаАнотація:
The speed at which an individual processes information, also referred to as reaction time (RT), is associated with attentional function and is commonly used as a measurement in the diagnosis of age related neurodegenerative disorders and commonly employed in ageing studies. In spite of the common use of information processing speed (RT) in ageing studies and as a diagnostic tool in neurodegenerative disorders, there is a lack of consensus regarding the most appropriate tests to use in the measurement of RT and a lack of consideration when it comes to both methodological and person-related factors that could influence test results. Still further, there is a marked lack of consideration of the idea that these tests may return different results between young adults and older adults, decreasing the overall reliability of the tests themselves. The purpose of the study was to complete an analysis of the test results of multiple RT tests in order to identify whether the study outcome of reaction time and its variability (intra-individual variability or IIV) in young adults and older adults was associated with the methodological factors of the type of test used to measure RT (and thus attentional function measured), the number of trials used and the participant hesitancy in responding; or whether variation occurred within test results due to non-clinical levels of anxiety experienced by the participant, and in relation to the possible/potential related factors, such as non-clinical depression levels, objectively measured general cognitive function, subjective memory function and educational level, sleep and sex. In the completion of the different phases of testing, analysis of the results showed that, in general, RT was slower, and IIV was greater, among older adults, as compared to the results obtained from the young adult group (in all tasks used). Levels of non-clinical anxiety were significantly higher in younger adults as compared to older adults. Although non-clinical anxiety levels could be linked with RT and IIV measures, the results varied concerning the task used, suggesting that this variability in result had to do with task type. Non-clinical levels of anxiety were correlated to sleep quality in specific areas for both younger and older adults, and that relationship was associated with RT, IIV, and attentional-related function in the completion of certain tasks or test types. These Ph.D. research findings may assist in improving clinical practice through the creation and integration of future evidence-based research practices.
12
Sauze, Martin J. "An investigation using empirical orthogonal functions and objective analysis to analyze the vertical temperature structure of a Gulf Stream meander." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1993. http://handle.dtic.mil/100.2/ADA265116.
Повний текст джерела
13
Macphee, Lauren Margaret. "An investigation of the identification of subjective and objective daytime cognitive failures in people with psychophysiological insomnia and good sleeper controls." Thesis, University of Glasgow, 2009. http://theses.gla.ac.uk/1658/.
Повний текст джерелаАнотація:
Individuals suffering from psychophysiological insomnia (PI) commonly report the experience of daytime cognitive deficits, such as poor concentration and an inability to complete daily tasks. The published nomenclature is consistent and reflective of these subjective accounts. However, to date there is little, or idiosyncratic, evidence of both subjective and objective daytime deficits in people with PI. This current study aims to assess whether daytime deficits can be detected in a PI population, through the inclusion of The Cognitive Failures Questionnaire (CFQ), a novel subjective report measure assessing everyday cognitive slips in functioning, and the Switching Attention Task (SAT), an objective psychomotor assessment. This current study has demonstrated that both the CFQ and the SATcomplex differentiate a group of PI from good sleeper controls (GS). The study concludes that the CFQ is a useful inclusion to PI research and provides more detailed evidence relating to the occurrence of daytime cognitive deficits in PI, however a measure with a stable multifactor may be more beneficial in future research. In addition, the significantly poorer performance of PI on the SATcomplex is discussed in relation to high cognitive load rather than gross cognitive deficit, and results from a SATsimple task and Digit Span Task aid this discussion and support the conclusion that deficits in PI are observed in relation to tasks that require the simultaneous activation of multiple cognitive resources.
14
Cornett, J. Yvette Farmer-Dougan Valeri. "An investigation of the reliability and validity of two transdisciplinary play-based assessment methods the open-ended and objective-based observation coding procedures /." Normal, Ill. Illinois State University, 1998. http://wwwlib.umi.com/cr/ilstu/fullcit?p9924345.
Повний текст джерелаАнотація:
Thesis (Ph. D.)--Illinois State University, 1998.Title from title page screen, viewed July 13, 2006. Dissertation Committee: Valeri Farmer-Dougan (chair), Mark E. Swerdlik, Jayne Bucy, Matthew Hesson-McInnis, Ming-Gon John Lian. Includes bibliographical references (leaves 108-112) and abstract. Also available in print.
15
Pako, Morongoa Rosina. "An investigation into reasons why Mogabane Community Garden Project did not reach its objective of poverty reduction and recommendations for reviving the project." Thesis, Nelson Mandela Metropolitan University, 2011. http://hdl.handle.net/10948/d1012023.
Повний текст джерелаАнотація:
There are three lines of poverty in South Africa, the first line is that of people living at less than R271 per month and constitute one third of the population (about 33 percent), second being those people living at less than R422 per month (50 percent of the population) and the last group being people living at less than R1 230 per month, constituting 79.1 percent of the population (Oosthuizen. 2008: 7 – 9). The poorest provinces are Eastern Cape and Limpopo with a poverty rate of 68.3 percent and 60.7 percent respectively, Western Cape and Gauteng the poverty rates are 20 percent and 28.8 percent respectively (United Nations Development Programme. 2003) To respond to the poverty challenges the government has come up with poverty alleviation strategies which were later translated into anti-poverty programmes. The Anti-poverty programmes undertaken by Government since 1994 can be grouped into various categories of public expenditure such as (Friedman and Bhengu, 2008:14), Social assistance and grants, Employment generating programmes, enterprise development and income support, Basic household security, Social services, Disaster relief and Employment related social insurance. This study assessed Mogabane Community Project to find out reasons why the project did not reach its objective of poverty reduction in the community. Qualitative Research methodology was used to arrive at the findings.
16
Wilcox, Michael Schnebly. "Trajectory Generation and Optimization for Experimental Investigation of Flapping Flight." BYU ScholarsArchive, 2013. https://scholarsarchive.byu.edu/etd/3953.
Повний текст джерелаАнотація:
Though still in relative infancy, the field of flapping flight has potential to have a far-reaching impact on human life. Nature presents a myriad of examples of successful uses of this locomotion. Human efforts in flapping flight have seen substantial improvement in recent times. Wing kinematics are a key aspect of this study. This study summarizes previous wing trajectory generators and presents a new trajectory generation method built upon previous methods. This includes a novel means of commanding unequal half-stroke durations subject to robotic trajectory continuity requirements. Additionally, previous optimization methods are improved upon. Experimental optimization is performed using the new trajectory generation method and a more traditional means. Methods for quantifying and compensating for sensor time-dependence are also discussed. Results show that the Polar Fourier Series trajectory generator advanced rapidly through the optimization process, especially during the initial phase of experimentation. The Modified Berman and Wang trajectory generator moved through the design space more slowly due to the increased number of kinematic parameters. When optimizing lift only, the trajectory generators produced similar results and kinematic forms. The findings suggest that the objective statement should be modified to reward efficiency while maintaining a certain amount of lift. It is expected that the difference between the capabilities of the two trajectory generators will become more apparent under such conditions.
17
Garcia, Alessandra Dias. "O juiz das garantias e a investigação criminal." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/2/2137/tde-23092015-092831/.
Повний текст джерелаАнотація:
A imprescindibilidade da atuação do magistrado na fase preliminar da persecução penal como garantidor dos direitos fundamentais do investigado é inegável. A consecução desse mister acarreta, porém, o comprometimento da imparcialidade objetiva do juiz para o julgamento do mérito. A atribuição das funções de atuar na fase de investigação preliminar e durante o processo a julgadores distintos foi o caminho que muitos ordenamentos trilharam para lidar com essa problemática. A mesma solução foi adotada pelo Projeto de Código de Processo Penal brasileiro PLS nº 156/2009, ao prever a figura do juiz das garantias, responsável pelo controle da legalidade da investigação criminal e pela salvaguarda dos direitos individuais. Essa figura, consentânea ao principio acusatório consagrado pela Constituição Federal de 1988, assegura a imparcialidade de forma muito mais efetiva, preservando o distanciamento do julgador dos elementos colhidos durante a investigação criminal.The indispensability of the judges involvement in the preliminary stage of criminal prosecution as a guarantor of the inquired person fundamentals rights is undeniable. However, this intervention compromises the impartiality of the judge on the judgment of the merits. The allocation of duties to act to different judges in the preliminary investigation phase and during the case was the way that many law systems have fallowed to handle this problem. The same solution was adopted by the Bill of the Brazilian Code of Criminal Procedure PLS nº 156/2009. The Bill provides the figure of the guarantee judge, which controls the legality of the criminal investigation and ensures the protection of individual rights. The guarantee judde, in accordance to the accusatory principle settleed in the Federal Constitution, assures a more effective impartiality preserving the distance of the judge from elements collected during criminal investigation.
18
Behrendorff, Carl David. "Social implications of radical technology adoption within the livestock industry - a design investigation: Innovating disruptive technologies in traditional marketplaces." Thesis, Queensland University of Technology, 2011. https://eprints.qut.edu.au/48127/1/Carl_Behrendorff_Thesis.pdf.
Повний текст джерелаАнотація:
This thesis presents a design investigation into how traditional technology-orientated markets can use design led innovation (DLI) strategies in order to achieve better market penetration of disruptive products. In a review of the Australian livestock industry, considering historical information and present-day trends, a lack of socio-cultural consideration was identified in the design and implementation of products and systems, previously been taken to market. Hence the adoption of these novel products has been documented as extremely slow. Classical diffusion models have typically been used in order to implement these products. However, this thesis poses that it is through the strategic intent of design led innovation, where heavily technology-orientated markets (such as the Australian livestock industry), can achieve better final adoption rates. By considering a range of external factors (business models, technology and user needs), rather than focusing design efforts solely on the technology, it is argued that using DLI approach will lead to disruptive innovations being made easier to adopt in the Australian livestock industry.
This thesis therefore explored two research questions:
1. What are the social inhibitors to the adoption of a new technology in the Australian livestock industry?
2. Can design be used to gain a significant feedback response to the proposed innovation?
In order to answer these questions, this thesis used a design led innovation approach to investigate the livestock industry, centring on how design can be used early on in the development of disruptive products being taken to market. This thesis used a three stage data collection programme, combining methods of design thinking, co-design and participatory design.
The first study found four key themes to the social barriers of technology adoption; Social attitudes to innovation, Market monitoring, Attitude to 3D imaging and Online processes. These themes were built upon through a design thinking/co-design approach to create three ‘future scenarios’ to be tested in participant workshops. The analysis of the data collection found four key socio-cultural barriers that inhibited the adoption of a disruptive innovation in the Australian livestock industry. These were found to be a lack of Education, a Culture of Innovation, a Lack of Engagement and Communication barriers. This thesis recommends five key areas to be focused upon in the subsequent design of a new product in the Australian livestock industry. These recommendations are made to business and design managers looking to introduce disruptive innovations in this industry. Moreover, the thesis presents three design implications relating to stakeholder attitudes, practical constraints and technological restrictions of innovations within the industry.
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Engen, Vegard. "Machine learning for network based intrusion detection : an investigation into discrepancies in findings with the KDD cup '99 data set and multi-objective evolution of neural network classifier ensembles from imbalanced data." Thesis, Bournemouth University, 2010. http://eprints.bournemouth.ac.uk/15899/.
Повний текст джерелаАнотація:
For the last decade it has become commonplace to evaluate machine learning techniques for network based intrusion detection on the KDD Cup '99 data set. This data set has served well to demonstrate that machine learning can be useful in intrusion detection. However, it has undergone some criticism in the literature, and it is out of date. Therefore, some researchers question the validity of the findings reported based on this data set. Furthermore, as identified in this thesis, there are also discrepancies in the findings reported in the literature. In some cases the results are contradictory. Consequently, it is difficult to analyse the current body of research to determine the value in the findings. This thesis reports on an empirical investigation to determine the underlying causes of the discrepancies. Several methodological factors, such as choice of data subset, validation method and data preprocessing, are identified and are found to affect the results significantly. These findings have also enabled a better interpretation of the current body of research. Furthermore, the criticisms in the literature are addressed and future use of the data set is discussed, which is important since researchers continue to use it due to a lack of better publicly available alternatives. Due to the nature of the intrusion detection domain, there is an extreme imbalance among the classes in the KDD Cup '99 data set, which poses a significant challenge to machine learning. In other domains, researchers have demonstrated that well known techniques such as Artificial Neural Networks (ANNs) and Decision Trees (DTs) often fail to learn the minor class(es) due to class imbalance. However, this has not been recognized as an issue in intrusion detection previously. This thesis reports on an empirical investigation that demonstrates that it is the class imbalance that causes the poor detection of some classes of intrusion reported in the literature. An alternative approach to training ANNs is proposed in this thesis, using Genetic Algorithms (GAs) to evolve the weights of the ANNs, referred to as an Evolutionary Neural Network (ENN). When employing evaluation functions that calculate the fitness proportionally to the instances of each class, thereby avoiding a bias towards the major class(es) in the data set, significantly improved true positive rates are obtained whilst maintaining a low false positive rate. These findings demonstrate that the issues of learning from imbalanced data are not due to limitations of the ANNs; rather the training algorithm. Moreover, the ENN is capable of detecting a class of intrusion that has been reported in the literature to be undetectable by ANNs. One limitation of the ENN is a lack of control of the classification trade-off the ANNs obtain. This is identified as a general issue with current approaches to creating classifiers. Striving to create a single best classifier that obtains the highest accuracy may give an unfruitful classification trade-off, which is demonstrated clearly in this thesis. Therefore, an extension of the ENN is proposed, using a Multi-Objective GA (MOGA), which treats the classification rate on each class as a separate objective. This approach produces a Pareto front of non-dominated solutions that exhibit different classification trade-offs, from which the user can select one with the desired properties. The multi-objective approach is also utilised to evolve classifier ensembles, which yields an improved Pareto front of solutions. Furthermore, the selection of classifier members for the ensembles is investigated, demonstrating how this affects the performance of the resultant ensembles. This is a key to explaining why some classifier combinations fail to give fruitful solutions.
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Dammerud, Jens Jørgen. "Stage acoustics for symphony orchestras in concert halls." Thesis, University of Bath, 2009. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.518296.
Повний текст джерела
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Pupeikienė, Lina. "Investigation and Applikation of Profilled Schools Schedulling Tasks Optimimization Methods." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2009. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2009~D_20090608_173743-06877.
Повний текст джерелаАнотація:
The problem of profiled school scheduling is important for Lithuanian schools and for similar schools in many other countries. No polynomial time methods are known for this problem.
The objective of this PhD thesis is to investigate heuristic methods for optimization of profiled school schedules. The convenience of application in real-life situations is provided by the vector optimization approach using platform-independent software implementation.
The task of experimental investigation is to select such parameters of heuristic methods that minimize expected deviation from the optimum.
Four optimization methods were regarded: Local Deterministic (LD), Local Randomized (LR), Simulated Annealing (SA), and SA with parameters optimized using the Bayesian approach (BA). The composite method of AM and BA provided the best results.
In Chapter 1 of the dissertation, various aspects of work of optimization methods as well as popular program languages suitable for school schedule optimization are analyzed. Literature about school scheduling is analysed.
In Chapter 2, conclusions are drawn how the optimization of heuristic parameters influences the speed and accuracy of finding the optimal solution. A technical rating analysis of popular schedule programs is made and technical disadvantages are listed. Criteria for evaluating the quality of results are proposed that include heuristic parameters in search of optimal schedules. Recommendations are states how to assess the choice and... [to full text]Profiliuotos mokyklos tvarkaraščio kūrimas yra aktualus uždavinys tiek Lietuvoje, tiek kitose šalyse. Nėra žinoma polinominių būdų šiai problemai spręsti. Pagrindinis šios daktaro disertacijos objektas yra ištirti euristinius metodus, skirtus profiliuotos mokyklos tvarkaraščio optimizavimui. Tvarkaraščio formavimo kriterijai, kurie yra reikalingi realiame gyvenime, nustatomi vektorinio optimizavimo metodais bei realizuojami nuo operacinės sistemos nepriklausoma programine įranga. Eksperimentinių tyrimų uždavinys – surasti tokius euristinių metodų parametrus, kurie minimizuotų numatytą nuokrypį. Disertacijoje aprašomi keturi optimizavimo metodai: lokalus determinuotas (LD), lokalus atsitiktinis (LA), atkaitinimo modeliavimo (AM) ir AM parametrų optimizavimas naudojant Bayes (BA) metodą. Kombinuotas AM ir Bayes metodas duoda geriausius rezultatus. Pirmajame apžvelgiama su mokyklos tvarkaraščių formavimu susijusi literatūra. Analizuojami tinkamiausi optimizavimo metodų darbo aspektai. Analizuojamos populiariausios programavimo kalbos, tinkančios kurti mokyklų tvarkaraščių optimizavimo programą. Antrajame skyriuje formuluojamas profiliuotų mokyklų tvarkaraščio kūrimo matematinis modelis. Analizuojami profiliuotose mokyklose naudojami euristiniai parametrai. Atlikti populiarių tvarkaraščių programų vertinimai ir analizės. Įvardijami šių programų trūkumai. Trečiajame skyriuje, remiantis 2 skyriaus analize ir išvadomis, pateiktas profiliuotos mokyklos lanksčios tvarkaraščio... [toliau žr. visą tekstą]
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Swilling, Benjamin John. "Human walking adaptations to distant limb mass disturbances : investigating biomimetic performance objectives." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/33911.
Повний текст джерелаАнотація:
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2005.Includes bibliographical references (leaves 101-103).
Online optimal trajectory planning is required in the control of humanoid robots, advanced prostheses, and impaired human limbs via functional neuromuscular stimulation . Optimization problems that involve complex, high degree of freedom simulations of the musculoskeletal system require extensive computational effort to solve. A methodology for generating optimal gait patterns in an online and computationally efficient manner is needed. It is the goal of this thesis to work towards the development of biologic performance criteria that can be utilized in finding solutions to reduced order walking optimization problems. Toward the development of biologically realistic performance criteria, human subjects were inertially-perturbed and the reorganization of gait quantitatively measured. Ten subjects walked at a self-selected speed with and without a 5 kg mass attached to the right ankle. Kinetic and kinematic data were collected for the weighted and unweighted conditions using ground force platforms and a multi-camera infrared tracking system, respectively. A 16 segment model of the body was built for each subject and a variety of kinematic, kinetic, and total system parameters calculated throughout the gait cycle.
(cont.) Additionally, the normal kinematic dataset was analyzed with a 5 kg mass virtually placed on the right ankle. The virtual mass dataset served as a known suboptimal solution as a basis for comparison. A Wilcoxon rank sign test was performed, and the ankle-weighted dataset was compared to normal. There were no significant changes in stride frequency, step length, stride length, or self-selected walking speed between the weighted and unweighted walking conditions. There were significant deviations in the kinematics of the right leg, but most were generally small with the exception of a decrease in maximum flexion angle of the affected leg during swing. In comparison to the virtual mass case to the true weighted case, it was determined that the reorganization of gait yields an increase in gait efficiency, a decrease in work to move the body center of mass, and a general reduction in reaction torque of the affected leg. It is suggested that the biologic performance objective consists of some function comprising of the energetic costs to move the body center of mass, gait efficiency, and joint reaction torques.
by Benjamin John Swilling.
S.M.
23
Jean-Louis, Odile. "Developing learners and learning in teacher education in the Seychelles: A critical investigation." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2005. https://ro.ecu.edu.au/theses/669.
Повний текст джерелаАнотація:
The development of education, and specifically, 'lifelong learners', 'professional-learning communities’ and a 'learning society' is one of the priorities of the Seychelles Government. This study focused on an issue fundamental to such development: the type of teacher education required to develop future citizens of the Seychelles into lifelong learners and to lead the country into a learning society. In the Seychelles a new National Curriculum was established in 1997, but to date little research has been undertaken in teacher education and existing programmes have remained intact.
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Soundararajan, Shvetha. "Assessing Agile Methods: Investigating Adequacy, Capability, and Effectiveness (An Objectives, Principles, Strategies Approach)." Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/23195.
Повний текст джерелаАнотація:
Agile methods provide an organization or a team with the flexibility to adopt a selected subset of principles and practices based on their culture, their values, and the types of systems that they develop. More specifically, every organization or team implements a customized agile method, tailored to better accommodate its needs. However, the extent to which a customized method supports the organizational objectives, i.e. the 'goodness' of that method, should be demonstrable. Existing agile assessment approaches focus on comparative analyses, or are limited in scope and application. In this research, we propose a systematic, comprehensive approach to assessing the 'goodness' of agile methods. We examine an agile method based on (1) its adequacy, (2) the capability of the organization to support the adopted principles and strategies specified by the method, and (3) the method's effectiveness. We propose the Objectives, Principles and Strategies (OPS) Framework to guide our assessment process. The Framework identifies (a) objectives of the agile philosophy, (b) principles that support the objectives and (c) strategies that implement the principles. It also defines (d) linkages that relate objectives to principles, and principles to strategies, and finally, (e) indicators for assessing the extent to which an organization supports the implementation and effectiveness of those strategies. The propagation of indicator values along the linkages provides a multi-level assessment view of the agile method. In this dissertation, we present our assessment methodology, guiding Framework, validation approach, results and findings, and future directions.Ph. D.
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Birkby, Josefin. "What was the purpose of this task? : An investigative study of students' perceptions of explicit task objectives." Thesis, Linnéuniversitetet, Institutionen för utbildningsvetenskap (UV), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-39411.
Повний текст джерелаАнотація:
Taking its starting point in the often debated subject of Swedish compulsory school students’ performance scores in surveys such as PISA and a lack of motivation towards schoolwork that transfers to low performance and does not facilitate a good learning climate, this study aims to investigate how teaching practice can affect this. The study is partly connected to formative assessment in that it focuses on one of the key strategies of the process; making the objectives and goals of schoolwork transparent to students and sharing these with them. Grounded in research both on formative assessment but also on motivation in connection to foreign language learning, it is hypothesised that sharing the objectives of a task with students will improve not only their performance on it, but also their motivation level and their perceptions of the task being of value to them and of benefit for their learning.The study employed a quasi-experimental approach where a group of 50 students were given five pairs of tasks out of which five were given without any explanation of the objectives (the A version) and five were given with an explanation of the objectives (the B version). Accompanying each task was a questionnaire and the answers to the questionnaires together with performance scores on the tasks served as the raw data for analysis. The study can be said to have strong ecological validity since it investigates teaching practice that commonly occurs in classrooms as teachers on an everyday basis choose to either share the objectives of schoolwork with their students, or do not.The analysis of the data gathered showed that there was no general improvement in performance scores on the B-version tasks where students were given an explanation of the objectives beforehand. Neither were they more motivated, nor felt that the tasks were more valuable or perceived they had learnt more. The findings thus pointed to the opposite of the hypothesised outcome. However, there proved to be a correlation between performance scores and motivation which in turn could encourage further research on the motivation of students in foreign language learning. A discussion of the manner in which the objectives and goals of tasks are communicated to students further opened up for a possible research angle to pursue where the focus would be not only on sharing the objectives with students but on discussing these and making them meaningful to students on a personal level.
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Kalmykova, Elena. "Dissolving Dualism : A Tripartite Model of Cognition for Religious Truth." Doctoral thesis, Uppsala universitet, Religionsfilosofi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-150622.
Повний текст джерелаАнотація:
This investigation can be described as a long journey to a final destination: a truth in religion. We start by considering dualism of the subjective and the objective, the classical model of cognition that underlies notions of truth. Dualistic notions of cognition lead to serious problems, especially for religious truth. Religions claim to state truths about the nature of the universe and human destiny, but these truths are incompatible. With a dualistic model this problem of diversity of religious truths leads to fundamentalism or relativism. Thus, this research aims to turn to the roots of the cognitive situation and investigate the way we cognize and relate to the world to provide a better model. As we consider the philosophical theories and empirical investigations of cognition, we come to the conclusion that dualism of the subjective and objective is not tenable. As the findings of contemporary mind sciences and phenomenologically oriented research indicate, human cognition is embodied, embedded, enacted, extended, and shaped by language. Thus, I propose to re-conceptualize the cognitive situation to provide a better philosophical account. I put forward a tripartite model of cognition, which unites language, action, and environment. The consequent application of this model to the issues of truth and religion shows that we can avoid the problem of diversity of truth claims. A tripartite model allows us to explain how we can maintain religion as true, despite the diversity of religious truth claims. Additionally, as this model is fundamental, its application leads to various new findings and inferences, which render anew the world and the way humans relate to it. Thus, our journey brings us to new frontiers of investigation.
27
Perkin, P. "An investigation into the relationship between farm and farmer characteristics and objectives among a sample of farmers in Berkshire." Thesis, University of Reading, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.332224.
Повний текст джерела
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Galant, Raashied. "The coalface of journalism: A qualitative research investigation into development communication objectives amongst rural newspapers in the Overberg District." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/4190.
Повний текст джерелаАнотація:
Thesis (MPhil (Journalism))--University of Stellenbosch, 2010.131 p.
This thesis explores how six commercial local newspapers based in the towns of Swellendam, Bredasdorp, Caledon and Gansbaai are reporting on gender and HIV/AIDS in ways that may help to shift specific attitudes as well as to generate appropriate community responses. The overall aim of the study is to advance theories around the location of commercial news media in the development context. It also aims to inform and empower development workers and activists on the opportunities or pitfalls in engaging with rural local media to advance their development goals. In most prior studies into the nature of gender or HIV/AIDS reporting in the media in South Africa, the focus has been exclusively on mainstream corporate and/or urbanbased media titles and very little investigation has been done into the performance of small ruralbased media. The study employs two methods of data collection namely, a quantitative content analysis of newspapers and structured interviews with the editors of the papers, and a sample group of government employees and community activists in the respective towns. The structured interviews provide a qualitative dimension to the content analysis, bearing in mind the dangers of quantifying media content and making isolated judgements on the actual context of journalistic practice. Through the interviews, the researcher has been able to explore the extent to which the perceptions of the media editors visavis a public interest role with respect to gender and HIV/AIDS actually differs from the quantitative evidence of their performance and the perceptions of key informants in their communities. The findings of the study suggest that local rural media hold out great hope with respect to the advancement of development communication goals through commercial media platforms. The editors in the four towns have established organic connections with their community, albeit tenuous, but which extend into the ranks of development workers in their towns. The data from the content analysis suggests that women enjoy high visibility in the pages of their local papers, and they are most likely to be portrayed as positive achievers than as women encountering violence. The tenuous nature of the connections between editor and community are most starkly evident around the issue of HIV/AIDS, with coverage of this being very low despite much work being undertaken in the community to deal with the pandemic. With respect to the issue of gender, there was demonstrable evidence from actual examples of content, that showed on the one hand the capacity to motivate for change in women's lives, but also on the other hand a danger of reinforcing attitudes that compound women's oppression. The study offers recommendations to a range of roleplayers to ensure, firstly, the continued survival of local rural newspapers, and also support in building capacity to see these papers mature into journalism products that are integrative and transformative.
Ford Foundation and the Media Development and Diversity Agency
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Magagula, Bonginkosi Wilfred. "The independence and objectives of the accident investigation functions of the Swaziland Civil Aviation Authority in light of the ICAO guidelines." Diss., University of Pretoria, 2015. http://hdl.handle.net/2263/53149.
Повний текст джерелаАнотація:
The need for any aviation authority to have an alert and more so, efficient accident or incident
investigation mechanism cannot be over emphasized particularly in present day aviation practice. It
is thus, in the best interest of any state, not only to be on the high alert in the event of an accident
occurring. As well as also having sufficient resources and expertise, to engage in the investigative
process. A significant factor to the carrying out of such investigations is off course, the manner in
which such process is regulated. More so because investigations of this nature can only be carried out
and addressed in a manner stipulated as a matter of law.
It would therefore follow, that the legislation which directly regulates the process in which the
investigations are carried out should be both succinct and clear. Further, it should also adhere
strictly to internationally established guidelines of due conduct in the occurrence of accidents.
Aircraft accident and incident investigations are central to the observance of safety in aviation as a
sector. Thus, the realization of aircraft safety in aviation is a central function of any aviation
authority. It is a role so central, that it is one that is internationally recognised and harmonised.
Though not a matter of enforced International law, international best practice in this field is
established in a convention, in particular the International Convention on Civil Aviation of 1944,
which is more commonly referred to as the Chicago convention. As all treaties and/or conventions
this is an opt?in regulatory mechanism, in which only member states bind themselves. Therefore,
where a state becomes a signatory to same and has bound itself, it is of crucial importance that it
observes the laws or regulations to which it has bound itself.
As a matter of course, individual state compliance at times even for mere ratification purposes has
proved over time to be a tricky process for numerous states. This is particularly prevalent in
developing countries. Some texts have attributed this to various aspects, such as lack of necessary expertise and resources amongst other factors. Whatever the reason however, it is important that
states eventually comply with regulations laid out in conventions, so as to achieve harmonisation in
processes of International applicability.
This research paper seeks to take an in depth look into to the extent to which Swaziland as a member
state of the Chicago convention, has achieved compliance with the set guidelines of the Chicago
Convention. However, the report will confine itself to aircraft safety as the focal point, and in
particular, focus on the specific regulatory mechanisms that relate to aircraft accident and incidents.Mini Dissertation (LLM)--University of Pretoria, 2015.
Public Law
LLM
Unrestricted
30
Liljekvist, Erika, and Oscar Hedlund. "Uncovering Signal : Simplifying Forensic Investigations of the Signal Application." Thesis, Högskolan i Halmstad, Akademin för informationsteknologi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-44835.
Повний текст джерелаАнотація:
The increasing availability of easy-to-use end-to-end encrypted messaging applications has made it possible for more people to conduct their conversations privately. This is something that criminals have taken advantage of and it has proven to make digital forensic investigations more difficult as methods of decrypting the data are needed. In this thesis, data from iOS and Windows devices is extracted and analysed, with focus on the application Signal. Even though other operating systems are compatible with the Signal application, such as Android, it is outside the scope of this thesis. The results of this thesis provide access to data stored in the encrypted application Signalwithout the need for expensive analysis tools. This is done by developing and publishing the first open-source script for decryption and parsing of the Signal database. The script is available for anyone at https://github.com/decryptSignal/decryptSignal.
31
Periannan, Vijayanand. "Investigation of the Effects of Various Energy and Exergy-Based Objectives/Figures of Merit on the Optimal Design of High Performance Aircraft System." Thesis, Virginia Tech, 2005. http://hdl.handle.net/10919/31405.
Повний текст джерелаАнотація:
This thesis work shows the advantages of applying exergy-based analysis and optimization methods to the synthesis/design and operation an Advanced Aircraft Fighter (AAF) with three subsystems: a Propulsion Subsystem (PS), an Environmental Control Subsystem (ECS), and an Airframe Subsys-tem - Aerodyanmics (AFS-A) is used to illustrate these advantages. Thermodynamic (both energy and exergy), aerodynamic, geometric, and physical models of the components comprising the subsystems are developed and their interactions defined. An exergy-based parametric study of the PS and its components is first performed in order to show the type of detailed information on internal system losses. This is followed by a series of constrained, system synthesis/design optimizations based on five different objective functions, which define energy-based and exergy-based measures of performance.
A first set of optimizations involving four of the objectives (two energy-based and two exergy-based) are performed with only PS and ECS degrees of freedom. Losses for the AFS-A are not incorporated into the two exergy-based objectives. The results show that as expected all four objectives globally produce the same optimum vehicle.A second set of optimizations is then performed with AFS-A degrees of freedom and again with two energy- and exergy-based objectives. However, this time one of the exergy-based objectives incorporates AFS-A losses directly into the objective. The results are that this latter objective produces a significantly better optimum vehicle. Thus, an exergy-based approach is not only able to pinpoint where the greatest inefficiencies in the system occur but produces a superior optimum vehicle as well by accounting for irreversibility losses in subsystems (e.g., the AFS-A) only indirectly tied to fuel usage.Master of Science
32
Jackson, Thomas Edwin. "Youth work in Northern Ireland : an investigation of current trends and objectives and their effectiveness, with special reference to the practice of cross-community intervention." Thesis, University of Ulster, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357789.
Повний текст джерела
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Kita, Lauren Elizabeth. "Investigating the relationship between sleep and postpartum depression : a longitudinal study examining the relationships between subjective and objective sleep during the perinatal period and postpartum depression." Thesis, Bournemouth University, 2013. http://eprints.bournemouth.ac.uk/21200/.
Повний текст джерелаАнотація:
Research has suggested that a bi-directional relationship exists between sleep disruption and depression. Not only is poor sleep a commonly reported symptom in those with depression, some aspects of sleep have also been shown to predict the onset of depression. Despite sleep problems being a commonly reported occurrence throughout the perinatal period, the field of perinatal sleep research remains in its relative infancy. However, recent studies suggest that sleep disturbances during this time may increase the risk of developing postpartum depression. Currently, research in this area is limited by studies that have failed to control for depressive symptoms at baseline, relied upon subjective, often retrospective, measures of sleep, and have only measured symptoms of postpartum depression in the early postpartum period. Few studies have used polysomnography, considered the ‘gold standard’ of sleep, and no studies to date have specifically compared the relationship between subjective and objective sleep. Therefore, the major aim of this thesis was to gain a better understanding of the specific aspects of sleep that were most relevant to postpartum depression. In order to address this aim, studies were carried out to: explore the aspects of sleep most relevant to major depressive disorder; examine differences in sleep between pregnant and non-pregnant women; investigate the relationships between subjective and objective measures of sleep; explore longitudinal changes in sleep, fatigue and depression throughout the perinatal period, and finally; examine which aspects of sleep at which time-point were most relevant to the development of postpartum depression. Overall this thesis found that women experience significant changes to their sleep throughout the perinatal period. While the sleep of third trimester women is considerably poorer than that of non-pregnant women (both objectively and subjectively), the most significant changes occur in the transition between late pregnancy and the early postpartum period. Furthermore, increased amounts of sleep and reports of difficulty falling asleep during late pregnancy predicted the development of postpartum depressive symptoms. This suggests that certain aspects of sleep during late pregnancy may serve as markers for women at risk of developing postpartum depression.
34
Smith, P. M. "An investigation into the nature of, and relationships between, educational objectives as stated and those inherent in related examination questions for auditing courses at South African universities." Master's thesis, University of Cape Town, 1987. http://hdl.handle.net/11427/17346.
Повний текст джерелаАнотація:
This study sets out to investigate the relationship between the stated and inherent auditing course objectives of selected South African universities. The need for congruence between the two is assumed. Stated auditing course objectives were established by means of a survey questionnaire to 17 South African universities. A panel of judges was used to perform an inferential analysis of 3 of these universities' related examination papers to determine their inherent course objectives. In addition, auditing practitioners were surveyed to establish what they considered desirable auditing course objectives at South African universities.
35
Al-Faidi, Al-Juhani Mohammed H. "Strategic Information Systems Planning (SISP) in the banking sector: An Investigation of Strategic Information Systems Planning (SISP) in the Saudi Banking Sector." Thesis, University of Bradford, 2011. http://hdl.handle.net/10454/17372.
Повний текст джерелаАнотація:
The improvement of SISP practices has rapidly become one of the most critical issues facing many organisations, including banks. Globally, the banking sectors, including the Saudi one, have developed and implemented many IS strategies. Several systems have been executed to support the countries’ economies which have benefited from the increased trading resulting from the greater flexibility in time and costs associated with banking transactions. To continue these achievements and to improve SISP processes, several factors require careful investigation based on their relationship to SISP success; which include SISP objectives, SISP internal factors, external consultant functions, SISP external factors, measurements of SISP success, key stakeholders’ roles, and triggers. Therefore this study investigates the impact of these factors on SISP success. Data were collected in three phases. Phase 1 was an initial study with one or two interviews with the IT directors of each bank in the Saudi banking sector comprising the central bank and 11 commercial banks. The outcomes informed the development of a survey that was used in Phase 2; to investigate a sample containing a central bank, a domestic commercial bank and a domestic-foreign commercial bank to determine their SISP processes. 157 completed questionnaires were returned from the bank executives, business and IT directors and consultants. In Phase 3, 57 interviews confirmed and explained the quantitative results from Phase 2. Therefore, an in-depth case study was made in the three banks during Phases 2 and 3. The research results support previous findings on the SISP’s seventeen objectives collected by several researchers across different industries and in various countries. Furthermore, the research condenses these seventeen objectives into five more practical and achievable objectives for the banking sector. These are: 1) planning and deployment of information systems; 2) leading organisation changes; 3) improving stakeholders’ involvement and communication; 4) achieving the strategic priorities; and 5) alignment of organisational policies and architecture for business and IS. In addition, the findings identify the factors according to their relationship with SISP success and therefore explore several elements with positive, negative or no impact on SISP success in the banking sector. The thesis presents conclusions and suggests areas for further research.
36
Mnene, Mthetheleli. "Investigating teaching and learning within three Eastern Cape reception year classrooms." Thesis, Rhodes University, 2012. http://hdl.handle.net/10962/d1003471.
Повний текст джерелаАнотація:
The purpose of this study is to explore the extent to which young children in three Grade R classes in the Eastern Cape Province were exposed to developmentally appropriate opportunities to achieve the Critical Outcomes as outlined in the South African National Curriculum Statement. The research took the form of a case study. Semi-structured interviews and observations were used to collect data. Respondents included children, their parents, Grade R practitioners and the school leadership. The findings tentatively showed that this set of parents perceived their role in providing for their children’s developmental needs as separate to that of the GR practitioners. They seemed to see their roles as helping their children to develop social and emotional competence only, and that the GR practitioners provided, in addition to this, literacy and numeracy teaching to their children. In contrast, the three GR practitioners believed that parents were responsible also for promoting literacy, numeracy and life skills. There seemed therefore to be a lack of clarity of specific teacher and parent views of their roles. The researcher found, however, that the children seemed to be given few developmentally appropriate opportunities for planned and structured activities which enabled them to explore the Critical Outcomes, for example, working together, solving problems, using technology. The teaching methodology used by the GR practitioners during the observation periods, seemed to a large extent, to be based in 'talk and chalk' in the plenary grouping. It did not seem to enable the implementation of the curriculum and especially of the Critical Outcomes in a developmentally appropriate way. In addition, the environment in which children learned was not observed to be developmentally appropriate for relevant education to take place. Too many children were crowded into the available space, while learning equipment and materials were lacking. Any competences that young children in these three GR programmes achieved were therefore possibly learned incidentally, rather than deliberately through planned activities. In addition, GR classes in this study were not observed to be supported within the schools to deliver competent curriculum activities to the children. The study makes suggestions to meet some of these challenges. These include improving the understanding of curriculum guidelines of all role players in the three schools, enabling the management teams and especially parents to take a stronger support and monitoring role, and providing and using materials and equipment to promote the use of the Critical Out comes as methods for teaching and for learning.
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Jimenez, Bree A., Pamela J. Mims, and Joshua N. Baker. "The Effects of an Online Data-Based Decisions Professional Development for In-service Teachers of Students with Significant Disability." Digital Commons @ East Tennessee State University, 2016. https://dc.etsu.edu/etsu-works/308.
Повний текст джерелаАнотація:
With the increase in the use of online professional development resources, especially for rural educators, this study evaluated the effects of online training modules on in-service teachers' ability to collect and use instructional progress monitoring data to make instructional decisions for students with significant disability (i.e., moderate to severe intellectual disability, autism). In this randomized control study, 29 teachers across three states participated in online data collection or data collection plus data-based decision making training. In addition, the generalization of teachers' ability to use data-based decisions with their own student outcome data were measured. Results indicated that while the modules did support teachers' acquisition of new information, they were not sufficient to carry over to applied use on their own students' data. Further discussion on the use of module-based professional development will be presented as well as how teachers in rural areas can access this information.
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Dang, Vinh Q. "Evolutionary approaches for feature selection in biological data." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2014. https://ro.ecu.edu.au/theses/1276.
Повний текст джерелаАнотація:
Data mining techniques have been used widely in many areas such as business, science, engineering and medicine. The techniques allow a vast amount of data to be explored in order to extract useful information from the data. One of the foci in the health area is finding interesting biomarkers from biomedical data. Mass throughput data generated from microarrays and mass spectrometry from biological samples are high dimensional and is small in sample size. Examples include DNA microarray datasets with up to 500,000 genes and mass spectrometry data with 300,000 m/z values. While the availability of such datasets can aid in the development of techniques/drugs to improve diagnosis and treatment of diseases, a major challenge involves its analysis to extract useful and meaningful information. The aims of this project are: 1) to investigate and develop feature selection algorithms that incorporate various evolutionary strategies, 2) using the developed algorithms to find the “most relevant” biomarkers contained in biological datasets and 3) and evaluate the goodness of extracted feature subsets for relevance (examined in terms of existing biomedical domain knowledge and from classification accuracy obtained using different classifiers). The project aims to generate good predictive models for classifying diseased samples from control.
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Piercy, Craig Allan. "An investigation of Multiple Objective Network Flows." 2001. http://purl.galileo.usg.edu/uga%5Fetd/piercy%5Fcraig%5Fa%5F200112%5Fphd.
Повний текст джерела
40
Bacquet, Carlos. "An Investigation of a Multi-Objective Genetic Algorithm applied to Encrypted Traffic Identification." Thesis, 2010. http://hdl.handle.net/10222/13016.
Повний текст джерелаАнотація:
This work explores the use of a Multi-Objective Genetic Algorithm (MOGA) for both, feature selection and cluster count optimization, for an unsupervised machine learning technique, K-Means, applied to encrypted traffic identification (SSH). The performance of the proposed model is benchmarked against other unsupervised learning techniques existing in the literature: Basic K-Means, semi-supervised K-Means, DBSCAN, and EM. Results show that the proposed MOGA, not only outperforms the other models, but also provides a good trade off in terms of detection rate, false positive rate, and time to build and run the model. A hierarchical version of the proposed model is also implemented, to observe the gains, if any, obtained by increasing cluster purity by means of a second layer of clusters. Results show that with the hierarchical MOGA, significant gains are observed in terms of the classification performances of the system.
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Wang, Chih-Ying, and 汪志穎. "Investigation of tool wear and multi-objective optimization in drilling of woven CFRP composite." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/16360745832181290568.
Повний текст джерелаАнотація:
碩士國立臺灣科技大學
機械工程系
105
This work examines cutting force, tool wear and hole quality with novel geometric designs, such as double-point and multi-facet drills with diamond coatings. Experiments were conducted with the variable of cutting speeds (50-180 m/min) and feed rates (0.05- 0.15 mm/rev) under dry conditions and use ANOVA to examine the signification of variables. To achieve the multi-objective optimization, we used Decision maker’s equation to build up the multi-objective optimization model. And use superposition process map to require the optimal range of parameters. The double-point drill presented various tool wear patterns, including chipping, delamination and fracture on the cutting lips. The tool wear patterns on the multi-facet drill included progressive abrasion wear, scoring and chipping along the cutting lips on the first, second and the third facets respectively. From the multi-objective optimization results under equal weighting of each objective, it suggested that the best combination for multi-facet drill is under the cutting speed of 50 m/min coupling with the feed rate of 0.05 mm/rev. In contrast, double-point drill was suggested to be used under the cutting speed of 110 m/min coupling with the feed rate of 0.05 mm/rev. When the threshold was set to be 25% of the range form experimental results, the superposition process map shows the preferable parameters of multi-facet drill are in the cutting speed of 50-55.46 m/min and the feed rate of 0.052-0.082 mm/rev. Double-point drill’s preferable parameters for out of roundness are distributed in the cutting speed of 110-137.37 m/min and the feed rate of 0.05-0.069 mm/rev. For first flank wear are distributed in the cutting speed of 158-180 m/min and the feed rate of 0.05-0.062 mm/rev.
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Tang, Yung-Hsu, and 湯詠旭. "Investigation of an Objective Function to Optimize a Micro-Peristaltic Pump with Slanted Membranes." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/71718314841733273808.
Повний текст джерелаАнотація:
碩士國立臺灣海洋大學
機械與機電工程學系
99
Most of micro-peristaltic pumps use three plane membranes as actuating membranes. Through sequential control of deflections of three membranes, a periodic peristaltic pumping motion is generated. We design a bi-directional micro pneumatic peristaltic pump driven by slanted membranes. Our micro-peristaltic pump has two opposite slanted membranes tandem along the fluid channel. It will produce continuous and asymmetric deflections under increasing pneumatic pressure. Experimental results show that our peristaltic pump achieves much higher maximum flow rate than that of a micro peristaltic pump with three flat membranes of similar size. Since the pumping performance of the peristaltic pump with slanted membranes depends highly on the thickness distribution of the membranes, the objective of this study is to find the optimal thickness distribution of membranes. We use the multi-physics feature of the simulation software CFD-RC to analyze the membrane deformation and fluid volume expelled downstream. The volume discharged downstream is used as the objective function to optimize the thickness distribution of a micro-peristaltic pump. The effect of the actuating pneumatic pressure is also investigated. Under the condition of 7000 N/m2 actuating pressure, the optimal volume discharged downstream for the rectangle membrane is increased by about 17.3% compared to a slanted membranes with linear thickness distribution.
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Wang, Peng. "A Systematic Investigation of Multi-Objective Evolutionary Algorithms Applied to the Water Distribution System Problem." Thesis, 2021. https://hdl.handle.net/2440/133074.
Повний текст джерелаАнотація:
Water distribution systems (WDSs) are one of society’s most important infrastructure assets. They consist of a great number of pumps, valves, junctions and a tremendous number of pipes that connect these nodes within the system, all of which induce a significant capital cost at the time of construction. However, there is no singular option for designing a WDS, and each potential design affects the cost and performance of the system differently (i.e., the pressure at each node and flow rates for each pipe). To identify solutions with a better trade-off between the cost and performance, multi-objective evolutionary algorithms (MOEAs) provide a robust optimisation tool to solve this type of problem. This PhD thesis focuses on improving and developing a more effective MOEA for WDS problems, and optimisation problems in general. The first stage of the research is to study the impact of select critical processes in MOEAs on algorithm performance and understand the reasons behind the performance observations. There are two chapters related to the first stage. The second stage is to develop a proposed General Multi-Objective Evolutionary Algorithm (GMOEA) and compare this with existing MOEAs for WDS problems. This is associated with the third content chapter.
In the first paper, the impact of the operators on an algorithm’s performance has been studied. The operators are the key component for exchange of information between solutions in populations to produce offspring solutions, thereby exploring alternative regions of the search space. These have a significant impact on an algorithm’s search behaviour. However, the composition and number of operators that should be included in an MOEA is generally fixed, based on choices made by the developers of these algorithms. To explore this issue, an assessment was conducted via comprehensive numerical experiments that isolate the influence of the size of the operator set, as well as its composition. In addition, the relative influence of other search processes affecting search behaviour (e.g., the selection strategy and hyperheuristic) have been studied. It has been found that operator set size is a dominant factor affecting algorithm performance, having a greater influence than operator set composition and other search processes affecting algorithm search behaviour. Moreover, it was also found that an existing MOEAs’ performance can be improved by simply increasing the number of operators used within the algorithm. This finding can be applied to justify the usage of operators for designing a new MOEA in the future.
In the second paper, a new convex hull contribution selection strategy for population-based MOEAs (termed CHCGen) has been proposed and compared with existing MOEAs in order to study the impact of the selection strategy on MOEA performance. It has been found that the CHCGen selection strategy is able to emphasise selection of the population of solutions on the convex hull of the non-dominated set of solutions. The CHCGen selection strategy has demonstrated that it can also improve an existing MOEAs’ performance. The finding suggests different selection strategies have an impact on MOEA performance. In addition, CHCGen can be used for developing a new MOEA in the future.
In the third paper, a new multi-objective evolutionary algorithm, called GMOEA(CHCGen,12,T,A)1 has been proposed by conducting comprehensive numerical experiments to determine the optimised component configuration for each MOEA process. The components considered within the algorithm construction include: the selection strategy, hyperheuristic, and operator set size. The numerical experiments not only explore the impact of each process’s component on algorithm performance comprehensively, but also investigate the correlation of each pairwise combination of the process’s components. In addition, the optimal form of the algorithm GMOEA(CHCGen,12,T,A) was compared with seven other existing MOEAs with an extended computational budget for a range of WDS problems. From the results, GMOEA(CHCGen,12,T,A) was shown not only to have outperformed all other MOEAs considered, but also to find a greater number of new Pareto front solutions for intermediate and large scale problems.Thesis (Ph.D.) -- University of Adelaide, School of Civil, Environmental and Mining Engineering, 2020
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CHER, TSANG SHAN, and 車參聖. "The Investigation Of The Criminal Responsibility Of Esthetic Medical Malpractice From The View Of Objective Imputation." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/12647465719140384661.
Повний текст джерелаАнотація:
碩士東吳大學
法律學系
101
Taiwan's current medical status encountered unprecedented difficulties, such as the so-called five major empty phenomenon, namely medicine ,surgery, gynecology, pediatrics, and emergency the five major medical departments gradually lose their members, as well as an increasing number of doctors adopt a more defensive healthcare. Such development trend is unhealthy for society, so that we can expect that the health care in the future is bound to suffer. The increasing frequency of medical malpractice, the patient suing the doctors more frequently by criminal litigation means ,and the increasing amount of compensation are the causes behind. Also the rising of the esthetic medicine market help the occurrence of these phenomenon. Esthetic medicine are different from general medicine , which is life-saving and health maintaining. The purpose of the general medicine rather correspond with the purpose of protection of legal interest by the criminal law . Esthetic medicine is purely for psychological satisfaction personally,and rather does not have a value in social welfare. Subsequently the esthetic medical practice should be evaluated more strictly than the general medical practice by criminal law. From the view of the theory of objective imputation, because the general medical practice have more value in social welfare, the general medical practice should be held criminally responsible only limited to gross negligence. On the other hand, the purpose of esthetic medical practice behavior is not for the protection of legal interest in the life-saving and health maintenance, the tolerance of esthetic medical practice behavior for crimical negligence should be lower than the general medical practice behavior. Based on increased frequency of medical disputes and avoiding being criminally sued , many non-cosmetic medical divisions physicians have joined into the esthetic medicine market. While these actions accelerate the hollowing of the medical industry and generate esthetic medicine chaos. So that in order to reduce the chaos and to protect consumer , but also to reduce the so-called five major empty phenomenon, the author proposed the limited decriminalization should be excluded from the application to the esthetic medicine.
45
Mahmoud, El Sayed. "An investigation of a novel analytic model for the fitness of a multiple classifier system." Thesis, 2012. http://hdl.handle.net/10214/4620.
Повний текст джерелаАнотація:
The growth in the use of machine learning in different areas has revealed challenging classification problems that require robust systems. Multiple Classier Systems (MCSs) have attracted interest from researchers as a method that could address such problems. Optimizing the fitness of an MCS improves its, robustness. The lack of an analysis for MCSs from a fitness perspective is identified.
To fill this gap, an analytic model from this perspective is derived mathematically by extending the error analysis introduced by Brown and Kuncheva in 2010. The model relates the fitness of an MCS to the average accuracy, positive-diversity, and negative-diversity of the classifiers that constitute the MCS. The model is verified using a statistical analysis of a Monte-Carlo based simulation. This shows the significance of the indicated relationships by the model. This model provides guidelines for developing robust MCSs. It enables the selection of classifiers which compose an MCS with an improved fitness while improving computational cost by avoiding local calculations.
The usefulness of the model for designing classification systems is investigated. A new measure consisting of the accuracy and positive-diversity is developed. This measure evaluates fitness while avoiding many calculations compared to the regular measures. A new system (Gadapt) is developed. Gadapt combines machine learning and genetic algorithms to define subsets of the feature space that closely match true class regions. It uses the new measure as a multi-objective criterion for a multi-objective genetic algorithm to identify the MCSs those create the subsets. The design of Gadapt is validated experimentally. The usefulness of the measure and the method of determining the subsets for the performance of Gadapt are examined based on five generated data sets that represent a wide range of problems. The robustness of Gadapt to small amounts of training data is evaluated in comparison with five existing systems on four benchmark data sets. The performance of Gadapt is evaluated in comparison with eleven existing systems on nine benchmark data sets. The analysis of the experiment results supports the validity of the Gadapt design and the outperforming of Gadapt on the existing systems in terms of robustness and performance.
46
Wu, Min Huei, and 吳敏慧. "On the Relationship between Objective, Strategy, and Effectiveness of Internet Advertising Providers - An Empirical Investigation in Taiwan." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/71652056147315219502.
Повний текст джерелаАнотація:
碩士中國文化大學
資訊管理研究所
89
This study takes stance on Internet advertising providers developing a model to ex-plore the relationship between Internet advertising objective, strategy, and effectiveness. The data of study is based on 98 effective questionnaires completed by Internet advertising providers. After using factor analysis, objective includes production mes-sage interactive, enterprise image, online sale, integrate marketing, and distinct market-ing and strategy includes theme strengthen, clerk design, database marketing, and present style and effectiveness includes sale, communication, and memory. Finally, the results of the path model show that the Internet advertising objective and strategy are positively related to effectiveness, and the Internet advertising objective is positively related to strategy. The result advises that Internet advertising enterprise should emphasize on mutual advertising communication and medium integration and make more reliable objective and strategy.
47
Mwesigye, Aggrey. "Thermal performance and heat transfer enhancement of parabolic trough receivers – numerical investigation, thermodynamic and multi-objective optimisation." Thesis, 2015. http://hdl.handle.net/2263/45963.
Повний текст джерелаАнотація:
Parabolic trough systems are one of the most commercially and technically developed
technologies for concentrated solar power. With the current research and development
efforts, the cost of electricity from these systems is approaching the cost of electricity from
medium-sized coal-fired power plants. Some of the cost-cutting options for parabolic trough
systems include: (i) increasing the sizes of the concentrators to improve the system’s
concentration ratio and to reduce the number of drives and controls and (ii) improving the
system’s optical efficiency. However, the increase in the concentration ratios of these systems
requires improved performance of receiver tubes to minimise the absorber tube
circumferential temperature difference, receiver thermal loss and entropy generation rates in
the receiver. As such, the prediction of the absorber tube’s circumferential temperature
difference, receiver thermal performance and entropy generation rates in parabolic trough
receivers therefore, becomes very important as concentration ratios increase. In this study, the thermal and thermodynamic performance of parabolic trough receivers at
different Reynolds numbers, inlet temperatures and rim angles as concentration ratios
increase are investigated. The potential for improved receiver thermal and thermodynamic
performance with heat transfer enhancement using wall-detached twisted tape inserts,
perforated plate inserts and perforated conical inserts is also evaluated.
In this work, the heat transfer, fluid flow and thermodynamic performance of a parabolic
trough receiver were analysed numerically by solving the governing equations using a
general purpose computational fluid dynamics code. SolTrace, an optical modelling tool that
uses Monte-Carlo ray tracing techniques was used to obtain the heat flux profiles on the
receiver’s absorber tube. These heat flux profiles were then coupled to the CFD code by
means of user-defined functions for the subsequent analysis of the thermal and
thermodynamic performance of the receiver. With this approach, actual non-uniform heat
flux profiles and actual non-uniform temperature distribution in the receiver different from
constant heat flux profiles and constant temperature distribution often used in other studies
were obtained.
Both thermodynamic and multi-objective optimisation approaches were used to obtain
optimal configurations of the proposed heat transfer enhancement techniques. For
thermodynamic optimisation, the entropy generation minimisation method was used.
Whereas, the multi-objective optimisation approach was implemented in ANSYS
DesignXplorer to obtain Pareto solutions for maximum heat transfer and minimum fluid
friction for each of the heat transfer enhancement techniques.
Results showed that rim angles lower than 60o gave high absorber tube circumferential
temperature differences, higher receiver thermal loss and higher entropy generation rates,
especially for flow rates lower than 43 m3/h. The entropy generation rates reduced as the inlet
temperature increased, increased as the rim angles reduced and as concentration ratios
increased. Existence of an optimal Reynolds number at which entropy generation is a
minimum for any given inlet temperature, rim angle and concentration ratio is demonstrated.
In addition, for the heat transfer enhancement techniques considered, correlations for the
Nusselt number and fluid friction were obtained and presented. With heat transfer
enhancement, the thermal efficiency of the receiver increased in the range 5% – 10%, 3% – 8% and 1.2% – 8% with twisted tape inserts, perforated conical inserts and perforated
plate inserts respectively. Results also show that with heat transfer enhancement, the absorber
tube’s circumferential temperature differences reduce in the range 4% – 68%, 3.4 – 56% and
up to 67% with twisted tape inserts, perforated conical inserts and perforated plate inserts
respectively. Furthermore, the entropy generation rates were reduced by up to 59%, 45% and
53% with twisted tape inserts, perforated conical inserts and perforated plate inserts
respectively. Moreover, using multi-objective optimisation, Pareto optimal solutions were
obtained and presented for each heat transfer enhancement technique.
In summary, results from this study demonstrate that for a parabolic trough system, rim
angles, concentration ratios, flow rates and inlet temperatures have a strong influence on the
thermal and thermodynamic performance of the parabolic trough receiver. The potential for
improved receiver thermal and thermodynamic performance with heat transfer enhancement
has also been demonstrated. Overall, this study provides useful knowledge for improved
design and efficient operation of parabolic trough systems.Thesis (PhD)--University of Pretoria, 2015.
tm2015
Mechanical and Aeronautical Engineering
PhD
Unrestricted
48
Chien, Hong-Yao, and 簡鴻耀. "Investigation of Curvature Effect on Optical Properties of the Light Guide Rod by Combined Multi-Objective Optimization Design." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/74767991606557373432.
Повний текст джерелаАнотація:
碩士國立高雄第一科技大學
工學院
101
The application of the light guide rod (LGR) has become increasingly common, but its complex and changing modeling is bringing about the light emitting uniform phenomenon. The main reason is that the spread of light is straight, and a turning point will be affected by the reflection or refraction. This paper aims to investigate the curvature effect on the LGR optical properties. The real-coded genetic algorithm (RGA) and grey relational analysis (GRA) in conjunction with Excel VBA combined with Solidworks and Lighttools softwares are employed together to find the best parameters from the limit specifications or the random values. In this paper, the total power (TP) rather than average power, average difference (AD) and contrast ratio (CR) are combined into a single parameter. Moreover, the area of light pattern is not fixed to avoid the incorrect mesh data in the “dark zone”. Finally it is validated by comparing with the previous results that the proposed design method can quickly and efficiently complete the LGR design when considering curvature effect on optical properties by changing the scattered particles in the LGR.
49
Galante, Rosa. "An investigation of subjective and objective sleepiness, performance and mood in patients with obstructive sleep apnoea and shift-workers." Thesis, 2011. https://vuir.vu.edu.au/19410/.
Повний текст джерелаАнотація:
Regardless of aetiology, constant sleep disruption results in wide-ranging negative consequences in sleepiness, psychomotor and driving performance, and mood. Individuals with obstructive sleep apnoea (OSA) and those engaged in the tumultuous routine of shift-work experience reduced sleep and poorer sleep quality which is likely to render these consequences more pronounced.
This study aimed to compare subjective and objective sleepiness, psychomotor performance, simulated driving performance and mood disturbances in OSA patients, shift-workers and control participants. This study also aimed to determine what relationships exist between subjective and objective sleepiness, performance and mood for the three groups and to obtain the correlates of accident risk based on a history of reported accidents in the preceding three years.
50
Yeh, Jih-Shan, and 葉濟賢. "An investigation of the policy objective of mobile communications spectrum planning/technical standards setting in Taiwan from the perspective of the development of mobile industry." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/90893286318949029933.
Повний текст джерелаАнотація:
碩士國立交通大學
經營管理研究所
87
This thesis investigates the development of Taiwan''s mobile communication industry and how the goal of the ''National Telecommunication Program'' for its local mobile communication industryon succeed the booming of the information and semiconductor industries as the new star industry can be achieved. To reach this goal, Taiwan''s mobile communication service sector and manufacturing sector must develop simultaneously toward becoming a balanced and complete industrial system. For establishing a sound mobile communications industrial development, this thesis studies feasible formations of Taiwan''s mobile communication industrial development from the direction of its mobile communication spectrum planning and technical standards setting. The methodology of this research first analyzes the development styles of advanced countries'' mobile communication industries while using them as the "ideal type" of industrial development. It comes out to four fundamental elements of analyzing mobile communication industries (spectrum planning, technical standards setting, manufacturing technology, and service offering). When using these four elements to compare the current development of Taiwan''s mobile communication industry with that of advanced countries, three problem gaps are discovered: Gap I - no conjunction between technical standards setting and manufacturing technology, Gap II - no conjunction between spectrum planning and manufacturing technology, and Gap III - no conjunction between service industry and manufacturing technology. The main cause of fractured development of Taiwan''s mobile communication industry is due to the three gaps from insufficient conjunction between service offering and the other three elements. This research, according to the three problem gaps and combining this industry''s spectrum planning and standards setting, develops the short-term and long-term strategy to fill the gaps and promote the full development of Taiwan mobile communication industry.