Dissertations / Theses: 'Slow management'

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Livingston, Peter Arthur. "Management of the Schmutzdecke layer of a slow sand filter." Thesis, The University of Arizona, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=3560794.

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Slow sand filters (SSF) have been used to treat surface water to drinking water standards for over a century. Today many cities, including London still treat surface waters to drinking water standards, however because there are viruses that are not efficiently removed by a slow sand filter and are not killed by chlorine, communities have turned to the use of micro filtration and/or reverse osmosis to provide safe drinking water. These technologies are much more efficient if organics are removed and turbidity reduced to less than 1 Nephelometric Turbidity Units (NTU). The greenhouse industry is another potential user of slow sand filters. They are not able to recycle irrigation drainage water without it being treated to reduce bacteria, virus, and fungi.

The objective of this research was to develop management strategies for SSF that specifically meet the needs of entities using SSF for pretreatment of potable water or use in a greenhouse. This data was used to test a scour system that resulted in scouring 80 percent of the organic layer in the filter and suspending the solids for 40 minutes. A conceptual design was done for a full scale SSF that took advantage of the scour and suspension data to clean the SSF at the end of a run cycle. SSF were able to consistently produce water with a turbidity less than 1 (NTU) and with the infiltration capacity of 0.27 m³m^-2. For greenhouse effluent a 1,000 square meter greenhouse that is discharging 3,600 L d^-1 of drainage water would require a 12.6 m² SSF, and the SSF for the community requiring treatment of 4.7 million liters per day of raw water was 730 m². The innovative cleaning system based on an air/water jet was developed to clean the SSF. Experiments were run to determine the amount of time that the solids were suspended and a scour system developed to exceed these times. The entire time for cleaning and recovery of the SSF was an average of 118 minutes for the greenhouse system and 170 minutes for the SSF serving a small community.

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Livingston, Peter. "Management of the Schmutzdecke Layer of a Slow Sand Filter." Diss., The University of Arizona, 2013. http://hdl.handle.net/10150/293439.

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Slow sand filters (SSF) have been used to treat surface water to drinking water standards for over a century. Today many cities, including London still treat surface waters to drinking water standards, however because there are viruses that are not efficiently removed by a slow sand filter and are not killed by chlorine, communities have turned to the use of micro filtration and/or reverse osmosis to provide safe drinking water. These technologies are much more efficient if organics are removed and turbidity reduced to less than 1 Nephelometric Turbidity Units (NTU). The greenhouse industry is another potential user of slow sand filters. They are not able to recycle irrigation drainage water without it being treated to reduce bacteria, virus, and fungi. The objective of this research was to develop management strategies for SSF that specifically meet the needs of entities using SSF for pretreatment of potable water or use in a greenhouse. This data was used to test a scour system that resulted in scouring 80 percent of the organic layer in the filter and suspending the solids for 40 minutes. A conceptual design was done for a full scale SSF that took advantage of the scour and suspension data to clean the SSF at the end of a run cycle. SSF were able to consistently produce water with a turbidity less than 1 (NTU) and with the infiltration capacity of 0.27 m³m⁻². For greenhouse effluent a 1,000 square meter greenhouse that is discharging 3,600 L d⁻¹ of drainage water would require a 12.6 m² SSF, and the SSF for the community requiring treatment of 4.7 million liters per day of raw water was 730 m². The innovative cleaning system based on an air/water jet was developed to clean the SSF. Experiments were run to determine the amount of time that the solids were suspended and a scour system developed to exceed these times. The entire time for cleaning and recovery of the SSF was an average of 118 minutes for the greenhouse system and 170 minutes for the SSF serving a small community.

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Mehrman, John M. "Centralized execution, decentralized control : why we go slow in defense acquisition." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/118538.

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Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, System Design and Management Program, 2018.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 121-125).
The slow pace to field new defense weapon systems is allowing potential adversaries to catch up to the technological advantage the U.S. has maintained since World War 11. Despite hundreds of studies, and a near constant state of "acquisition reform", the problem continues. This research analyzed the defense acquisition process as a socio-technical system, focusing on the source selection process as subset of the Defense Acquisition System (DAS) for modeling purposes to investigate the value of the separation of contracting and program management authorities. Network graphs showed how Conway's law predicted the effect of the separation of authorities on the topographic structure of the source selection process and a high network distance between the separate authorities. An agent-based model was built that showed a 26% cost (112 days) in terms of schedule because of the separation of authorities. The benefit of the separation was investigated by scoring the comments received by the Multi-Functional Independent Review Team (MIRT) for five different source selections and found that less than 1 % of comments had a likely impact on the decision and less than 4% had a likely or highly likely impact on protestability. The results showed that while there is a small benefit to the separation of authorities currently implemented in the source selection process, the cost is very high. Enough data and evidence were generated to recommend taking steps to better structurally combine the two authorities and better integrate source selection expertise into the process.
by John M. Mehrman.
S.M. in Engineering and Management

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Wiese, Jonas Verfasser], and Eric [Akademischer Betreuer] [Sucky. "Slow Logistics – eine simulationsgestützte Analyse der ökonomischen und ökologischen Potentiale der Sendungsbündelung / Jonas Wiese ; Betreuer: Eric Sucky." Bamberg : University of Bamberg Press, 2017. http://d-nb.info/1127042610/34.

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Gilbert, David E. "Deep change or slow death? a practical road guide for the highway of change /." Theological Research Exchange Network (TREN) Access this title online, 2004. http://www.tren.com.

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Laborde, Sylvain. "Slow-paced breathing and cardiac vagal activity : influence on stress regulation, sleep, and cognitive executive performance The effect of slow-paced breathing on stress management in adolescents with intellectual disability Influence of a 30-day slow paced breathing intervention compared to social media use on subjective sleep quality and cardiac vagal activity The influence of slow-paced breathing on executive function Influence of slow-paced breathing on inhibition after physical exertion." Thesis, Normandie, 2019. http://www.theses.fr/2019NORMC044.

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Cette thèse de doctorat a pour but d'étudier l’influence de la respiration lente contrôlée sans biofeedback sur l'activité vagale cardiaque ainsi que son action sur plusieurs processus d'autorégulation, en se basant sur le modèle d'intégration neuroviscérale (Smith et al., 2017 ; Thayer et al., 2009) et sur le modèle de résonance (Lehrer & Gevirtz, 2014). Quatre études ont été menées, auprès d'adolescents ayant un handicap mental (étude 1) et de jeunes adultes sains (études 2, 3 et 4). Les effets d’interventions courtes et longues basées sur la respiration lente contrôlée ont été étudiés, et des effets positifs ont été constatés sur la gestion du stress (intervention courte, étude 1), le sommeil (intervention longue, étude 2) et les fonctions exécutives (intervention courte, études 3 et 4), mais les effets sur les fonctions exécutives n'ont pas été médiés par l’activité vagale cardiaque. Ces résultats sont encourageants en ce qui concerne l'utilisation de la respiration lente contrôlée en tant qu’intervention à court et long terme, en tant que "solution rapide" ou routine quotidienne, mais les recherches futures doivent clarifier les mécanismes sous-jacents, en particulier en utilisant des méthodes d'imagerie cérébrale. En conclusion, la respiration lente contrôlée est une technique gratuite, non invasive, simple à mettre en œuvre, et avec peu d'effets secondaires, ce qui en fait une intervention appropriée pour traiter un éventail varié de phénomènes liés à l’autorégulation
This PhD thesis was aimed to investigate the influence of slow-paced breathing (SPB) without biofeedback on CVA, as well as its action on several self-regulation processes, based on the neurovisceral integration model (Smith et al., 2017; Thayer et al., 2009) and on the resonance model (Lehrer & Gevirtz, 2014). Four studies were conducted, adolescents with individual disabilities (Study 1) and healthy young adults (Study 2, 3, & 4). Both short-term and long-term SPB interventions have been investigated, and positive effects have been found on stress management (short-term, Study 1), sleep (long-term, Study 2), and executive functions (short-term, Studies 3 and 4), however results related to executive functions were not mediated by CVA. These results are encouraging regarding the use of SPB in acute and chronic interventions, as a “quick-fix” or daily routine, however future research has to clarify the underlying mechanisms, in particular with brain imaging methods. To conclude, SPB is a technique that is free, non-invasive, easy to implement, and with little side effects, which makes it an appropriate intervention to recommend to address a large range of self-regulation phenomena

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Hudson, Mark. "The slow co-production of disaster : wildfire, timber capital, and the United States Forest Service /." view abstract or download file of text, 2007. http://proquest.umi.com/pqdweb?did=1335359621&sid=1&Fmt=2&clientId=11238&RQT=309&VName=PQD.

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Thesis (Ph. D.)--University of Oregon, 2007.
Typescript. Includes vita and abstract. Includes bibliographical references (leaves 183-205). Also available for download via the World Wide Web; free to University of Oregon users.

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Vinson, Stan Wayne. "Leadership Development in Financial Institutions in South Dakota: A Slow Growth State." Antioch University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=antioch1317259766.

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Badenhorst, Leon. "A study into the slow rate of energy conservation in the base metal refinery of Anglo American Platinum (Amplats)." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/21385.

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Thesis (MBA)--Stellenbosch University, 2012.
The consumption of energy results in environmental costs, which include resource shortages, air pollution and radioactive wastes. Due to the economic cost associated, more and more Western industrial organisations are investing in innovative technologies to reduce energy consumption through improved thermal insulation of buildings, modifying equipment and by using energy-saving devices. The organisations are, however, not assured of any savings unless employees handle apparatus and equipment in a manner that conserves energy. Therefore, the important question to answer is how organisational behaviour can be changed to improve and enhance energy conservation efforts. Anglo American Platinum (Amplats) has identified that it needs to change its operations to conserve energy, thus ultimately conserving the planet. The company has identified an internal goal of reducing its energy consumption by fifteen percent, without sacrificing output, over a period of ten years from 2004. Current (2011) energy consumption at the Rustenburg Base Metals Refinery (RBMR) facility indicates that the mentioned goal does not seem achievable in 2014 as anticipated. The proposition to this phenomenon is that the prevailing culture at RBMR is not conducive to a conservation culture as required to conserve energy. Organisational culture is the pattern of values, norms, beliefs, attitudes and assumptions that shape the ways in which people behave and things get done. This hypothesis was tested with a culture survey in the form of an environmental questionnaire. The findings from the questionnaire confirm cultural barriers to achieving centralised targets and goals. Responses to the questionnaire indicated that the organisation does not measure energy conservation efforts accurately and that the information on how to attain the required conservation is not sufficient. The respondents further indicated that they have very limited input into energy conservation efforts and that trust issues present themselves as barriers to achieving set goals and targets. The prevailing perception by the respondents is that inadequate recognition systems are in place to drive the required savings. A surprising finding of the research is that the level of education of the respondents showed no significance with regard to energy conservation and the environment in general. A second interesting finding was that most respondents felt that they could do something to conserve energy and thereby conserve the environment. The challenge facing Amplats is to transform this awareness into a vehicle that will produce significant and sustainable results. Clear and decisive action will be required to bring about cultural change.

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Cosgrove, Rex M. "Optimization and Analysis of the Effects of Temperature, pH, and Injection Techniques on a Slow-Release Permanganate Gel for DNAPL Remediation." Ohio University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1595851093961511.

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Bouhafs, Ilana. "La fabrique de la transition : construire, diffuser et négocier le sens de la soutenabilité au sein des chaînes d'approvisionnement textile." Thesis, Université de Lille (2022-....), 2022. http://www.theses.fr/2022ULILD007.

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Alors que le dernier rapport du GIEC (2022) tire une nouvelle fois la sonnette d'alarme, il apparaît crucial pour les chercheurs en sciences de gestion de s'intéresser aux processus susceptibles de transformer nos modes de production et de consommation pour les rendre plus soutenables. En s'inscrivant dans les transition studies, et en mobilisant conjointement la perspective multi-niveaux et les travaux de Karl Weick relatifs aux processus de construction et de diffusion du sens (Weick, 1989, 1995, 2005), notre travail de thèse vise à identifier les micro-fondations de la transition et ce en vue de comprendre comment les individus influencent celle-ci et le management des chaînes d'approvisionnement textile (Geels, 2020). Grâce à une étude de cas multiple et compréhensive, mobilisant des méthodes plurielles (entretiens semi-directifs, observations et données secondaires et de presse), nous reconstituons les processus de construction de sens traversés par des collaborateurs d'enseignes de distribution, des dirigeants industriels, mais également des entrepreneurs. Plusieurs interprétations de la transition et leurs répercussions sur le management de la chaîne d'approvisionnement ont pu être identifiées. Elles sont les suivantes : « produire mieux », « produire moins » et « produire avec ». Celles-ci témoignent de compréhensions de la soutenabilité plus ou moins fortes, et aboutissent à des modèles de management de la chaîne d'approvisionnement variés bien que le plus souvent complémentaires : le management circulaire, local, équitable, frugal et collaboratif. Nos travaux nous poussent à considérer la transition, mais également les modèles de management des chaînes d'approvisionnement qui en sont issus comme des concepts éminemment interprétatifs. Résultats de processus sociaux, ils sont influencés par l'interaction et les dispositifs intermédiaires
The latest IPCC report (2022) sounds the alarm bell on the acceleration and intensification of climate change. More than ever, researchers should focus their attention on processes likely to transform our production and consumption patterns to make them more sustainable. Rooted in the field of transition studies, and more especially on the multilevel perspective, and by jointly mobilizing Karl Weick's work on sensemaking and sensegiving (Weick, 1989, 1995, 2005), our reseach aims to bring a new understanding of transition by identifying its micro-foundations and more specifically by understanding how individuals influence both transition and supply chain management (Geels, 2020).Thanks to a multiple and comprehensive case study, mobilizing several methods (semi-structured interviews, observations, and secondary data and press archives), we retrace sensemaking processes of retailers' employees, industrial leaders, and entrepreneurs, and identify both their action and their justifications. Several interpretations of transition, with specific repercussions on supply chain management had been identified. According to our findings, both transition and supply chain management models should be considered as eminently interpretative concepts. Resulting of social processes, they are influenced by interaction and which can also be influenced by intermediary devices

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Nencková, Lucie. "Současný stav a nakládání s textilním odpadem z domácností v ČR." Doctoral thesis, Vysoká škola ekonomická v Praze, 2017. http://www.nusl.cz/ntk/nusl-264704.

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Proper consumer attitude towards textile products and optimal post-consumer waste management of textile waste is connected with many benefits. Despite this fact, little research has been conducted on these topics. Textile waste represented mainly by donated textile from households and its material flow in waste streams mirrors the behaviour of our consumer society as well as new technologies in textile and fashion industry. More information about consumer attitude and behaviour toward textile and textile waste is needed to provide suitable waste management processes according to the hierarchy of waste management, such as re-use and energy recovery, and to ensure sustainable development and minimal impact on the worlds wellbeing. This study takes into account not only waste management of textile waste, but also tries to understand all textile issues in a wider perspective. Particularly fashion industry is connected with many negative ethical aspects (e.g. sweatshops), and many environmental issues are connected with overproduction of lower-quality textile products. Proper handling of post-consumer textile products is only one of the product life cycle stages to be solved. The main goal of this study is to discuss the results of a consumer attitude and behaviour questionnaire toward textile and textile waste from households in the Czech Republic. The study also includes partial hypotheses and an analysis of interest groups as other possible sources of information to form proper textile waste management policy tools and strategies.

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Martinsson, Erik, Emil Martinsson, and Sören Säf. "IWESS, an integrated water, energy and sanitation solution : A holistic approach to reach sustainability trough organic waste management for the Lake Victoria Basin, Kenya." Thesis, University of Skövde, School of Technology and Society, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-566.

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The process of allocating necessary resources like clean water, fuel/energy and food have resulted in an unsustainable use of natural resources causing problems with Soil erosion, soil fertility, desertification, deforestation, eutrophication and global warming. The purpose of this study was to gain information on the functional design of a waste management system enabling the organic components of domestic waste to be processed as useful resources while at the same time allow them to be re-circulated. The main part of this study was carried out at the Kendu SDA Hospital in the Rachyonyo district in western Kenya. For the case of this study two main objectives where chosen. The first was to develop a principal technological solution using three classed “appropriate technologies” found suitable for the purpose namely biogas, ecological water treatment systems and slow sand filtration. The second was to further analyse each included technology to further develop their potential to fit the concept. Results from the pilot facilities where then to be retrieved from the actual component selection and construction process itself, with performance analysis left for future studies.

The main purpose of the biogas system study has been to evaluate the original ideas of overall concept, details, materials and construction methods. The 1 m3 biogas system has improved significantly during the development process and is today not far from an implementation, i.e. construction on a slightly larger scale. The biogas system developed during the project has proven to have potential for digestion of both latrine and kitchen waste. Using the two as fuel for the process does not only remove a problem – it grants several benefits.

The ecological waste water treatment system main objective was to design and construct a pilot SSF-wetland. Results show that the construction process for smaller scaled SSF systems is simple and does not require trained personnel or specialized equipment and that significant cost reduction can be made by using locally available materials.

The slow sand filtration sub system concept is called PT SCX and though still in the stage of development proved to have great potential concerning both efficiency and sustainability. The PT SCX comprises the advantages of slow sand filtration with further development of individual system solutions. It was adapted to enable both integration to the IWESS solution and stand alone installations purifying even highly turbid surface water sources to drinking water quality.

The result from the study confirms the suitability of the three included technologies, ecological waste water treatment, biogas and slow sand filtration to work in an integrated system called IWESS- Integrated Water Energy and Sanitation Solution. The combined subsystems can together with source separated sewage offer full resource recovery enabling recirculation of both nutrients and water. In addition the system can be designed as a net producer of renewable and emission free energy.

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Goldsmith, David. "Local Fashionalities : Växbo Lin and WomenWeave." Licentiate thesis, Högskolan i Borås, Institutionen Textilhögskolan, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-3713.

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Global Fashion, via the logic of high-speed, large-scale industrial production and anachronistic high-volume consumption habits, causes significant social and environmental damage. Local Fashion isunderstood as part of the Slow Fashion movement that aims to change the functions of fashion so that they support or lead the quest to flourish within known human and planetary boundaries.This Licentiate thesis examines, through an exploratory narrative based on new and existing research, two Local Fashionalities. Växbo Lin is a small linen manufacturer/brand in Hälsingland, Sweden, producing new heritage home textiles. WomenWeave is a handloom social enterprise inMadhya Pradesh, India, making naya khadi. Their approaches and practices are presented and discussed vis-à-vis notions of “globality”, “locality”, design management, and the quest for sustainability.The narrative aims to improve understandings of what Local Fashion is, and contribute to the effort to design new fashion systems grounded in logic relevant to contemporary human needs and aspirations.

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Sjöström, Charlotte, and Emma Ungerman. "Europas framtida konfektionsmarknad : dess förutsättningar för att återfå en stark position." Thesis, Högskolan i Borås, Institutionen Textilhögskolan, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-16821.

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Textil- och konfektionsindustrin blir alltmer globaliserad och ställs inför hårdare krav då konsumenterna efterfrågar allt billigare varor i snabb förändring. Sedan flera decennier har europeiska konfektionsföretag flyttat sin tillverkning till länder med lägre arbetskostnader för att uppfylla kraven om låga priser som europiska tillverkare har svårt att uppfylla. En stor del har flyttats till Kina men även till andra länder i Asien. Nu håller marknadsförhållandena på att förändras igen genom tillväxt- och utvecklingsländernas starka utveckling. Förändringarna syns tydligast på Kinas marknad genom stigande priser och mindre kapacitet för europeisk produktion. Detta skapar nya förutsättningar för hur företagen väljer att planera sina verksamheter och resulterar i att detaljhandelsföretagen ser sig om efter alternativa produktionsländer.Syftet med studien är att ta reda på om konfektionstillverkningens tyngdpunkt kommer att fortsätta att ske i Asien eller om det finns förutsättningar för europeisk konfektionsindustri att återhämta sig och bli konkurrenskraftig i förhållande till tillverkningen i Asien eller om konfektionsindustrin istället kommer att etableras i andra globala regioner. För att uppnå detta syfte utformades en kvalitativ studie i form av semistrukturerade djupintervjuer med nio svenska konfektionsföretag samt en stiftelse verksam inom textil- och konfektionsindustrin. Studien har kompletterats med dokument utformade av organisationer kopplade till EU samt vetenskapliga artiklar.Undersökningen påvisar att Kinas förändrade situation inte leder till en större återväxt för Europas textil- och konfektionsproduktion. Tyngdpunkten av konfektionsproduktion inom den närmsta framtiden kommer att ligga kvar i Asien men flyttas från Kina till nya lågkostnadsländer i regionen. Europa kommer med sannolikhet inte att bedriva någon massproduktion i framtiden och de förlorar alltmer produktion inom låg- och mellanprissegmentet till övriga regioner. Delar av europeiska företags produktion kommer inom den närmsta tiden att fortsätta ske inom Europa, då ingen annan region i dagsläget kan uppfylla behoven av korta ledtider, effektiv logistik, små serier, stabilitet och hög kvalitet lika bra. Med tiden kommer troligtvis en allt större del att produceras i Nordafrika som i framtiden kan komma att ta över en betydande del av både Asiens och Europas produktion.The textile- and clothing industry is becoming increasingly globalized and face even tougher requirements as consumers demand for cheaper goods in rapid change. For several decades the European apparel companies have moved their manufacturing to countries with lower labour costs to meet the requirements of low prices. A major part has been moved to China, but also to other countries in Asia. Now the market conditions are changing again because of the strong growth of emerging and developing countries. The changes are most evident in China's market where prices are rising and capacity is decreasing for European production. This creates new conditions for how the retail companies choose to plan their activities and results in that they look for alternative production countries.The purpose of this study is to determine if the emphasis of clothing manufacturing will continue to occur in Asia or whether there are grounds for European clothing industry to recover and become competitive in relation to production in Asia or if production instead will be established in other global regions. To achieve this purpose we executed a qualitative study in the form of semi-structured interviews with nine Swedish clothing companies and a foundation working in the textile- and clothing industry. The study has been supplemented with documents written by organizations linked to the EU and scientific articles.The survey shows that China's changing situation does not lead to a major regeneration of European textile- and clothing production. The emphasis of clothing production will in the near future remain in Asia, although move from China to the new low-cost countries in the region. Europe will probably not mass produce clothing in the future and they lose more and more production in low-and mid-range market to other regions. Parts of the European company's production will in the near future continue to take place in Europe, as no other region currently can meet the needs of short lead times, efficient logistics, small batches, stability and quality as well. Over time, probably more production will occur in North Africa which in the future may take over a significant part of both Asian and European production.
Program: Textilekonomutbildningen

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Milner, Joseph M. (Joseph Micah). "Dynamic slot allocation with airline participation." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/11882.

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Sankararaman, Ravi. "Impact assessment of dynamic slot exchange in air traffic management." College Park, Md. : University of Maryland, 2004. http://hdl.handle.net/1903/2320.

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Thesis (M.B.A.) -- University of Maryland, College Park, 2004.
Thesis research directed by: Robert H. Smith School of Business. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.

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Abdulgadir, Adil, and Imad Abdulgadir. "Strategic Proposals for Sustainable Supply Chains in the Fast Fashion Industry : Exploring ways to incorporate concepts and methods to confront the damaging effects of the industry." Thesis, KTH, Industriell ekonomi och organisation (Inst.), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-285949.

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Accounted as the second largest cause of pollution, the fashion industry is only behind the petroleum industry worldwide. In recent decades, the supply chains of retail companies have become international with the growth of a global economy. As a result, fashion companies have increasingly shifted their supply chains into developing countries with cheaper labour. The shift is made possible due to their lower environmental awareness and looser environmental regulatory systems. This dominant business model within the clothing industry has gained enormous traction within recent decades and has been coined with the term fast fashion. However, due to the negative economic, social and environmental impact, mainly in developing countries, fast fashion companies increasingly focus on sustainability efforts within their supply chains to ensure the same quality and standards in production and working conditions. The thesis seeks to investigate what efforts have to be done within the supply chains of fast fashion companies in order to become more sustainable. A case study is conducted with a fashion retailer based in Sweden, referred to as Company X, through several semi-structured interviews in order to explore how Company X manages to keep a competitive advantage through its extensive sustainability efforts within its supply chain. The findings and analysis of this study show that there are numerous supply chain strategies for improvements, including sustainable manufacturing, eco-material preparations, green distribution, ethical consumers and reshoring vs. offshoring strategies. The major competitive advantages that are achieved according to the company itself come from; a shift from labour-intensive suppliers to capital-intensive, strong brand image, credibility, increase in ethical consumers, partnerships, transparency and traceability. Conclusively, purchasing from capital-intensive suppliers rather than labour-intensive suppliers will yield new innovative solutions for technologically advanced eco-material as well as efficiency in the production process. Furthermore, it was found that for a reshoring strategy to become the norm in the near future, extensive work and research is required. Lastly, as consumers' behaviour shifts towards a more ethical mindset, traditional fast fashion companies will continue to lose an important customer segment if no changes are made.
Modebranschen är den näst största orsaken till föroreningar världen över bakom oljeindustrin. Under de senaste decennierna har försörjningskedjor för detaljhandelsföretag blivit internationella med tillväxten av en global ekonomi. Som ett resultat har modeföretag i allt högre grad flyttat sina försörjningskedjor till utvecklingsländer med billigare arbetskraft. Förändringen möjliggörs på grund av deras lägre miljömedvetenhet och lösare miljörätt. Denna dominerande affärsmodell har fått ett enormt fäste inom klädindustrin under de senaste decennierna och har myntats med termen fast fashion. Men på grund av den negativa ekonomiska, sociala och miljömässiga påverkan, främst i utvecklingsländer, fokuserar snabbmodeföretag alltmer på hållbarhetsinsatser inom sina försörjningskedjor. Detta görs för att säkerställa samma kvalitet och standarder i produktions- och arbetsförhållanden. Arbetet har i syfte att undersöka vilka insatser som måste göras inom fast fashion-industrins försörjningskedjor för att bli mer hållbara. En fallstudie genomförs med ett modeföretag baserad i Sverige, kallad Company X, genom flera semistrukturerade intervjuer för att utforska hur de lyckas behålla konkurrensfördelar genom sitt omfattande hållbarhetsarbete inom sin försörjningskedja. Resultaten och analyserna av denna studie visar att det finns många strategier för förbättringar inom försörjningskedjan, inklusive hållbar tillverkning, miljövänliga preparat, grön distribution, etiska konsumenter och reshoring kontra offshoring-strategier. De stora konkurrensfördelarna som uppnås enligt företaget själva kommer från; en övergång från arbetsintensiva leverantörer till kapitalintensiva, stark varumärkesimage, trovärdighet, ökade etiska konsumenter, partnerskap, transparens och spårbarhet. Avslutningsvis så kommer köp från kapitalintensiva leverantörer, snarare än arbetskraftsintensiva leverantörer, leda till nya innovativa lösningar för tekniskt avancerade miljömaterial såväl som effektiviseringar i produktionsprocessen. Dessutom konstateras det att för att en reshoring-strategi ska bli normen inom en snar framtid krävs omfattande arbete och forskning. När konsumenternas beteende skiftar mot en mer etisk inställning, kommer traditionella fast fashion-företag att fortsätta att förlora ett viktigt kundsegment om inga förändringar görs.

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19

Malik, Zeeshan. "Towards on-line domain-independent big data learning : novel theories and applications." Thesis, University of Stirling, 2015. http://hdl.handle.net/1893/22591.

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Feature extraction is an extremely important pre-processing step to pattern recognition, and machine learning problems. This thesis highlights how one can best extract features from the data in an exhaustively online and purely adaptive manner. The solution to this problem is given for both labeled and unlabeled datasets, by presenting a number of novel on-line learning approaches. Specifically, the differential equation method for solving the generalized eigenvalue problem is used to derive a number of novel machine learning and feature extraction algorithms. The incremental eigen-solution method is used to derive a novel incremental extension of linear discriminant analysis (LDA). Further the proposed incremental version is combined with extreme learning machine (ELM) in which the ELM is used as a preprocessor before learning. In this first key contribution, the dynamic random expansion characteristic of ELM is combined with the proposed incremental LDA technique, and shown to offer a significant improvement in maximizing the discrimination between points in two different classes, while minimizing the distance within each class, in comparison with other standard state-of-the-art incremental and batch techniques. In the second contribution, the differential equation method for solving the generalized eigenvalue problem is used to derive a novel state-of-the-art purely incremental version of slow feature analysis (SLA) algorithm, termed the generalized eigenvalue based slow feature analysis (GENEIGSFA) technique. Further the time series expansion of echo state network (ESN) and radial basis functions (EBF) are used as a pre-processor before learning. In addition, the higher order derivatives are used as a smoothing constraint in the output signal. Finally, an online extension of the generalized eigenvalue problem, derived from James Stone’s criterion, is tested, evaluated and compared with the standard batch version of the slow feature analysis technique, to demonstrate its comparative effectiveness. In the third contribution, light-weight extensions of the statistical technique known as canonical correlation analysis (CCA) for both twinned and multiple data streams, are derived by using the same existing method of solving the generalized eigenvalue problem. Further the proposed method is enhanced by maximizing the covariance between data streams while simultaneously maximizing the rate of change of variances within each data stream. A recurrent set of connections used by ESN are used as a pre-processor between the inputs and the canonical projections in order to capture shared temporal information in two or more data streams. A solution to the problem of identifying a low dimensional manifold on a high dimensional dataspace is then presented in an incremental and adaptive manner. Finally, an online locally optimized extension of Laplacian Eigenmaps is derived termed the generalized incremental laplacian eigenmaps technique (GENILE). Apart from exploiting the benefit of the incremental nature of the proposed manifold based dimensionality reduction technique, most of the time the projections produced by this method are shown to produce a better classification accuracy in comparison with standard batch versions of these techniques - on both artificial and real datasets.

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20

Yuen, Siu Yu. "Routing and time-slot assignment algorithms and connection management in photonic circuit switched networks /." View abstract or full-text, 2005. http://library.ust.hk/cgi/db/thesis.pl?ELEC%202005%20YUEN.

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21

Ngan, Chiu Chung. "Is mediation an effective alternative dispute resolution method to resolve building management disputes?" access abstract and table of contents access full-text, 2007. http://libweb.cityu.edu.hk/cgi-bin/ezdb/dissert.pl?ma-slw-b22446072a.pdf.

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Thesis (M.A.)--City University of Hong Kong, 2007.
"Submitted in partial fulfillment of the requirements for Master of Arts in arbitration and dispute resolution, LW 6409 dissertation." Title from PDF t.p. (viewed on Apr. 1, 2008) Includes bibliographical references.

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22

Lam, Lysander Ping-chuen. "Efficacy of managing disputes arising from the daily management and maintenance of private buildings in Hong Kong." access abstract and table of contents access full-text, 2006. http://libweb.cityu.edu.hk/cgi-bin/ezdb/dissert.pl?ma-slw-b21847654a.pdf.

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Thesis (M.A.)--City University of Hong Kong, 2006.
"MA in arbitration and dispute resolution final year dissertation." Title from PDF t.p. (viewed on May 23, 2007) Includes bibliographical references.

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23

Watson, Eric. "Sun-Synchronous Orbit Slot Architecture Analysis and Development." DigitalCommons@CalPoly, 2012. https://digitalcommons.calpoly.edu/theses/760.

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Space debris growth and an influx in space traffic will create a need for increased space traffic management. Due to orbital population density and likely future growth, the implementation of a slot architecture to Sun-synchronous orbit is considered in order to mitigate conjunctions among active satellites. This paper furthers work done in Sun-synchronous orbit slot architecture design and focuses on two main aspects. First, an in-depth relative motion analysis of satellites with respect to their assigned slots is presented. Then, a method for developing a slot architecture from a specific set of user defined inputs is derived.

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24

Noyes, Connor David. "Characterization of the Effects of a Sun-Synchronous Orbit Slot Architecture on the Earth's Orbital Debris Environment." DigitalCommons@CalPoly, 2013. https://digitalcommons.calpoly.edu/theses/1026.

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Low Earth orbit represents a valuable limited natural resource. Of particular interest are sun-synchronous orbits; it is estimated that approximately 44% of low Earth satellites are sun-synchronous. A previously developed sun-synchronous orbit slot architecture is considered. An in-depth analysis of the relative motion between satellites and their corresponding slots is performed. The long-term evolution of Earth's orbital environment is modeled by a set of coupled ordinary differential equations. A metric for quantifying the benefit, if any, of implementing a sun-synchronous architecture is developed. The results indicate that the proposed slot architecture would reduce the frequency of collisions between satellites in sun-synchronous orbits.

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25

Lang, Magdalena Anna Katharina Verfasser], Michael [Akademischer Betreuer] [Schneider, and Eva Catherine [Akademischer Betreuer] Cleophas. "Time slot management for attended home deliveries: integrating revenue management and vehicle routing for dynamic and stochastic control / Magdalena Anna Katharina Lang ; Michael David Schneider, Eva Catherine Cleophas." Aachen : Universitätsbibliothek der RWTH Aachen, 2020. http://d-nb.info/1225401860/34.

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26

Lang, Magdalena Anna Katharina [Verfasser], Michael [Akademischer Betreuer] Schneider, and Eva Catherine [Akademischer Betreuer] Cleophas. "Time slot management for attended home deliveries: integrating revenue management and vehicle routing for dynamic and stochastic control / Magdalena Anna Katharina Lang ; Michael David Schneider, Eva Catherine Cleophas." Aachen : Universitätsbibliothek der RWTH Aachen, 2020. http://d-nb.info/1225401860/34.

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27

Rios, Ricardo Araújo. "SLOT: uma ferramenta dinâmica para escalonamento global de aplicações em grades computacionais." Universidade Federal de São Carlos, 2008. https://repositorio.ufscar.br/handle/ufscar/401.

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Made available in DSpace on 2016-06-02T19:05:34Z (GMT). No. of bitstreams: 1 2082.pdf: 3574461 bytes, checksum: e92a97c5bb512846ce12d22f63592a23 (MD5) Previous issue date: 2008-05-19
Financiadora de Estudos e Projetos
The constant improvement in performance that computers and interconnection networks present has favored the use of distributed computational resources, and given rise to Grid Computing. This new approach uses heterogeneous and geographically distributed resources to resolve problems with high computational costs. The execution of applications in this environment is generally achieved with scheduling mechanisms that manipulate the task set and its interdependences, mapping the tasks on to the resources. However, existing schedulers generate the schedule of each application individually, not evaluating the impact on the execution of previously scheduled applications. In this sense, this work presents a global scheduling tool for the tasks submitted to the Grid, and also presents a scheduling algorithm that allocates tasks between previously scheduled slots of time. The use of the proposed tool and algorithm permit a reduction in the amount of time processors remain idle and therefore a more efficient execution of the applications.
A melhoria constante de desempenho que os computadores e as redes de interconexão vêm apresentando favoreceu o uso de recursos computacionais distribuídos, dando origem à Computação em Grade. Esta nova abordagem utiliza recursos heterogêneos e geograficamente distribuídos, a fim de resolver problemas de grande custo computacional. A execução de aplicações neste ambiente geralmente é realizada por meio de mecanismos de escalonamento que manipulam os conjuntos de tarefas e suas interdependências, mapeando-as de forma eficiente nos recursos. Contudo, os escalonadores existentes atualmente realizam o escalonamento de cada aplicação individualmente, deixando de avaliar o impacto na execução de aplicações previamente escalonadas. Neste sentido, este trabalho apresenta uma ferramenta de escalonamento global das tarefas submetidas para a Grade e apresenta ainda um algoritmo de escalonamento que aloca as tarefas em fatias de tempo livre entre tarefas previamente escalonadas. A utilização da ferramenta e do algoritmo propostos permite a redução dos períodos de tempo ociosos nos processadores e a execução das aplicações de forma mais eficiente quando comparado com algoritmos tradicionais.

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28

Hafner, Florian. "IMPROVING AIRLINE SCHEDULE RELIABILITY USING A STRATEGIC MULTI-OBJECTIVE RUNWAY SLOT ASSIGNMENT SEARCH HEURISTIC." Doctoral diss., University of Central Florida, 2008. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3259.

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Improving the predictability of airline schedules in the National Airspace System (NAS) has been a constant endeavor, particularly as system delays grow with ever-increasing demand. Airline schedules need to be resistant to perturbations in the system including Ground Delay Programs (GDPs) and inclement weather. The strategic search heuristic proposed in this dissertation significantly improves airline schedule reliability by assigning airport departure and arrival slots to each flight in the schedule across a network of airports. This is performed using a multi-objective optimization approach that is primarily based on historical flight and taxi times but also includes certain airline, airport, and FAA priorities. The intent of this algorithm is to produce a more reliable, robust schedule that operates in today's environment as well as tomorrow's 4-Dimensional Trajectory Controlled system as described the FAA's Next Generation ATM system (NextGen). This novel airline schedule optimization approach is implemented using a multi-objective evolutionary algorithm which is capable of incorporating limited airport capacities. The core of the fitness function is an extensive database of historic operating times for flight and ground operations collected over a two year period based on ASDI and BTS data. Empirical distributions based on this data reflect the probability that flights encounter various flight and taxi times. The fitness function also adds the ability to define priorities for certain flights based on aircraft size, flight time, and airline usage. The algorithm is applied to airline schedules for two primary US airports: Chicago O'Hare and Atlanta Hartsfield-Jackson. The effects of this multi-objective schedule optimization are evaluated in a variety of scenarios including periods of high, medium, and low demand. The schedules generated by the optimization algorithm were evaluated using a simple queuing simulation model implemented in AnyLogic. The scenarios were simulated in AnyLogic using two basic setups: (1) using modes of flight and taxi times that reflect highly predictable 4-Dimensional Trajectory Control operations and (2) using full distributions of flight and taxi times reflecting current day operations. The simulation analysis showed significant improvements in reliability as measured by the mean square difference (MSD) of filed versus simulated flight arrival and departure times. Arrivals showed the most consistent improvements of up to 80% in on-time performance (OTP). Departures showed reduced overall improvements, particularly when the optimization was performed without the consideration of airport capacity. The 4-Dimensional Trajectory Control environment more than doubled the on-time performance of departures over the current day, more chaotic scenarios. This research shows that airline schedule reliability can be significantly improved over a network of airports using historical flight and taxi time data. It also provides for a mechanism to prioritize flights based on various airline, airport, and ATC goals. The algorithm is shown to work in today's environment as well as tomorrow's NextGen 4-Dimensional Trajectory Control setup.
Ph.D.
Department of Industrial Engineering and Management Systems
Engineering and Computer Science
Industrial Engineering PhD

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Doss, Sasha Stevely. "Managing Muskellunge in the New River, Virginia: Effective Regulations and Predation on Smallmouth Bass." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/77440.

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Potential predation between fishes of recreational interest has incited many bitter conflicts between angler groups. Large predators, such as esocids, are often at the center of these conflicts because of their capacity to alter fish populations. Such a conflict certainly exists between the Muskellunge Esox masquinongy and Smallmouth Bass Micropterus dolomieu fisheries of the New River, Virginia. Following the institution of a 42-in minimum-length limit (MLL) on Muskellunge, bass anglers feared that increased Muskellunge abundance might be negatively affecting Smallmouth Bass via increased predation. In order to ascertain the impacts of the 42-in MLL, I estimated the demographics, abundance, and food habits of Muskellunge combined with bioenergetics modeling to assess changes (i) in the quality of the Muskellunge fishery and (ii) in Muskellunge predation on Smallmouth Bass. Additionally, given the likelihood of future regulations to incite similar concerns from bass anglers, I modeled alternative length-limit regulations (iii) to assess their potential to improve fishery quality, thereby laying the groundwork for managers to address angler concerns before they arise. I found substantial increases in population size structure and in average adult density of Muskellunge since the institution of the 42-in MLL, but bioenergetics modeling did not indicate a notable increase in the consumption of Smallmouth Bass. I also found that high MLLs (e.g., 48-in) were likely to promote the largest increases in trophy production of Muskellunge compared to low MLLs or protected-slot limits (PSLs). This study suggests that the current Muskellunge population likely plays a small role in shaping Smallmouth Bass population dynamics and production in the New River; and lays the groundwork for predicting how the impact of Muskellunge on Smallmouth Bass might change under alternative regulations.
Master of Science

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30

McCrea, Michael Victor. "Slot-Exchange Mechanisms and Weather-Based Rerouting within an Airspace Planning and Collaborative Decision-Making Model." Diss., Virginia Tech, 2006. http://hdl.handle.net/10919/26874.

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We develop and evaluate two significant modeling concepts within the context of a large-scale Airspace Planning and Collaborative Decision-Making Model (APCDM) and, thereby, enhance its current functionality in support of both strategic and tactical level flight assessments. The first major concept is a new severe weather-modeling paradigm that can be used to assess existing tactical en route flight plan strategies such as the Flight Management System (FMS) as well as to provide rerouting strategies. The second major concept concerns modeling the mediated bartering of slot exchanges involving airline trade offers for arrival/departure slots at an arrival airport that is affected by the Ground Delay Program (GDP), while simultaneously considering issues related to sector workloads, airspace conflicts, as well as overall equity concerns among the airlines. This research effort is part of an $11.5B, 10-year, Federal Aviation Administration (FAA)-sponsored program to increase the U.S. National Airspace (NAS) capacity by 30 percent by the year 2010. Our innovative contributions of this research with respect to the severe weather rerouting include (a) the concept of â Probability-Netsâ and the development of discretized representations of various weather phenomena that affect aviation operations; (b) the integration of readily accessible severe weather probabilities from existing weather forecast data provided by the National Weather Service (NWS); (c) the generation of flight plans that circumvent severe weather phenomena with specified probability levels, and (d) a probabilistic delay assessment methodology for evaluating planned flight routes that might encounter potentially disruptive weather along its trajectory. Given a fixed set of reporting stations from the CONUS Model Output Statistics (MOS), we begin by constructing weather-specific probability-nets that are dynamic with respect to time and space. Essential to the construction of the probability-nets are the point-by-point forecast probabilities associated with MOS reporting sites throughout the United States. Connections between the MOS reporting sites form the strands within the probability-nets, and are constructed based upon a user-defined adjacency threshold, which is defined as the maximum allowable great circle distance between any such pair of sites. When a flight plan traverses through a probability-net, we extract probability data corresponding to the points where the flight plan and the probability-net strand(s) intersect. The ability to quickly extract this trajectory-related probability data is critical to our weather-based rerouting concepts and the derived expected delay and related cost computations in support of the decision-making process. Next, we consider the superimposition of a flight-trajectory-grid network upon the probability-nets. Using the U.S. Navigational Aids (Navaids) as the network nodes, we develop an approach to generate flight plans that can circumvent severe weather phenomena with specified probability levels based on determining restricted, time-dependent shortest paths between the origin and destination airports. By generating alternative flight plans pertaining to specified threshold strand probabilities, we prescribe a methodology for computing appropriate expected weather delays and related disruption factors for inclusion within the APCDM model. We conclude our severe weather-modeling research by conducting an economic benefit analysis using a k-means clustering mechanism in concert with our delay assessment methodology in order to evaluate delay costs and system disruptions associated with variations in probability-net refinement-based information. As a flight passes through the probability-net(s), we can generate a probability-footprint that acts as a record of the strand intersections and the associated probabilities from origin to destination. A flight planâ s probability-footprint will differ for each level of data refinement, from whence we construct route-dependent scenarios and, subsequently, compute expected weather delay costs for each scenario for comparative purposes. Our second major contribution is the development of a novel slot-exchange modeling concept within the APCDM model that incorporates various practical issues pertaining to the Ground Delay Program (GDP), a principal feature in the FAAâ s adoption of the Collaborative Decision-Making (CDM) paradigm. The key ideas introduced here include innovative model formulations and several new equity concepts that examine the impact of â at-least, at-mostâ trade offers on the entire mix of resulting flight plans from respective origins to destinations, while focusing on achieving defined measures of â fairnessâ with respect to the selected slot exchanges. The idea is to permit airlines to barter assigned slots at airports affected by the Ground Delay Program to their mutual advantage, with the FAA acting as a mediator, while being cognizant of the overall effect of the resulting mix of flight plans on air traffic control sector workloads, collision risk and safety, and equity considerations. We start by developing two separate slot-exchange approaches. The first consists of an external approach in which we formulate a model for generating a set of package-deals, where each package-deal represents a potential slot-exchange solution. These package-deals are then embedded within the APCDM model. We further tighten the model representation using maximal clique cover-based cuts that relate to the joint compatibility among the individual package-deals. The second approach significantly improves the overall model efficiency by automatically generating package-deals as required within the APCDM model itself. The model output prescribes a set of equitable flight plans based on admissible trades and exchanges of assigned slots, which are in addition conformant with sector workload capabilities and conflict risk restrictions. The net reduction in passenger-minutes of delay for each airline is the primary metric used to assess and compare model solutions. Appropriate constraints are included in the model to ensure that the generated slot exchanges induce nonnegative values of this realized net reduction for each airline. In keeping with the spirit of the FAAâ s CDM initiative, we next propose four alternative equity methods that are predicated on different specified performance ratios and related efficiency functions. These four methods respectively address equity with respect to slot-exchange-related measures such as total average delay, net delay savings, proportion of acceptable moves, and suitable value function realizations. For our computational experiments, we constructed several scenarios using real data obtained from the FAA based on the Enhanced Traffic Management System (ETMS) flight information pertaining to the Miami and Jacksonville Air Route Traffic Control Centers (ARTCC). Through our experimentation, we provide insights into the effect of the different proposed modeling concepts and study the sensitivity with respect to certain key parameters. In particular, we compare the alternative proposed equity formulations by evaluating their corresponding slot-exchange solutions with respect to the net reduction in passenger-minutes of delay for each airline. Additionally, we evaluate and compare the computational-effort performance, under both time limits and optimality thresholds, for each equity method in order to assess the efficiency of the model. The four slot-exchange-based equity formulations, in conjunction with the internal slot-exchange mechanisms, demonstrate significant net savings in computational effort ranging from 25% to 86% over the original APCDM model equity formulation. The model has been implemented using Microsoft Visual C++ and evaluated using a C++ interface with CPLEX 9.0. The overall results indicate that the proposed modeling concepts offer viable tools that can be used by the FAA in a timely fashion for both tactical purposes, as well as for exploring various strategic issues such as air traffic control policy evaluations; dynamic airspace resectorization strategies as a function of severe weather probabilities; and flight plan generation in response to various disruption scenarios.
Ph. D.

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31

Kim, Sang Hyun. "Airport control through intelligent gate assignment." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/50277.

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This dissertation aims at improving the efficiency, robustness, and flexibility of airport operations through intelligent gate assignment. Traditional research on gate assignment focuses on the accommodation of passengers' demands such as walking time of passengers, and the robustness of gate assignment. In spite of its importance on the ramp operations, there is a lack of research to account ramp congestion when gates are assigned. Therefore, this dissertation proposes a new perspective on the gate assignment that accounts for ramp congestion. For that purpose, a ramp operations model based on observations at Atlanta airport is presented to understand the characteristics of aircraft movement on the ramp. The proposed gate assignment problem minimizes passenger-time spent on ramp areas. In addition, this dissertation is conducted to satisfy the needs of passengers, aircraft, and operations from the perspectives of passengers. Using actual passenger data at a major hub airport, the proposed gate assignment is assessed by means of passengers' transit time, passengers' time spent on the ramp, and passengers' waiting time for a gate. Results show that the proposed gate assignment outperforms the current gate assignment in every metric. This dissertation also analyzes the impact of gate assignment on departure metering, which controls the number of pushbacks in order to reduce airport congestion. Then, some of departing flights are held at gates, so it increases the chance of gate conflict, which reduces the efficiency of departure metering as well as ramp operations. In order to analyze the impact of gate assignment on departure metering, this dissertation simulates departure processes at two airports. Results show that the proposed robust gate assignment reduces the occurrence of gate conflicts under departure metering and helps to utilize gate-holding times to some extent.

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Nokam, Kuaté Donald. "Cryptographie homomorphe et transcodage d’image/video dans le domaine chiffré." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS575/document.

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L'apparition de nouvelles technologies comme l'informatique en nuages (cloud computing) offre de nouvelles opportunités de traitement de l'information. Par exemple, il est désormais facile de stocker ses photos ou vidéos personnelles sur des serveurs distants. Il est également possible de partager ces contenus à travers ces mêmes serveurs, ou encore via les réseaux sociaux ou les plateformes de téléchargement. Cependant, ces données personnelles sont bien souvent accessibles par le fournisseur de service, essentiellement pour des raisons pratiques : par exemple adapter une vidéo pour qu'elle s'affiche au bon format quel que soit l'appareil utilisé pour la visionner, permettre le partage de ses contenus avec d’autres personnes, etc. Cela soulève cependant un problème de confidentialité de ces données personnelles, et de confiance dans le fournisseur du service. La cryptographie classique apporte des solutions à ce problème, mais soulève malheureusement celui de la maniabilité des données : il devient par exemple impossible d'adapter un contenu vidéo au bon format d'affichage puisque le fournisseur ne peut plus « voir » la vidéo. Une solution alternative réside toutefois dans le chiffrement homomorphe. Cet outil un peu magique de la cryptographie avancée apporte la même sécurité que les algorithmes de cryptographie classique, mais permet de plus de manipuler les données tout en conservant leur forme chiffrée. Il offre ainsi une nouvelle perspective pour les fournisseurs puisque ceux-ci peuvent continuer à traiter l'information sans être capable de la voir, et donc sans atteinte à la vie privée de leurs utilisateurs, se conformant ainsi au nouveau Règlement Général sur la Protection des Données (RGPD). Bien que le chiffrement homomorphe soit très souvent considéré comme insuffisamment mature, du fait de sa complexité algorithmique, cette thèse cherche à montrer son caractère prometteur, en s'intéressant à son usage pour le traitement d'images et de vidéos chiffrées à la source. Nous regardons ainsi les différents algorithmes qui constituent un encodeur d'image/vidéo (JPEG/H264 et HEVC) et les transformons en des circuits qui sont manipulables par des systèmes de chiffrement homomorphes. Nous proposons ainsi dans cette thèse le tout premier pipeline de compression d'images de type JPEG ("homomorphic-JPEG") sur des pixels qui sont chiffrés de bout-en-bout. Pour optimiser la gestion des données ainsi protégées, nous proposons également de nouveaux outils applicables à tous les schémas de chiffrement homomorphe sur les réseaux idéaux. Notre approche permet de maximiser le nombre de slots dans un chiffré et introduit de nouvelles fonctions pour manipuler ces différents slots de manière indépendante les uns des autres. Ces travaux de thèse ont abouti à la publication de deux articles dans des conférences internationales ainsi qu’à la soumission d'un article supplémentaire
The emergence of new technologies like cloud computing brings new opportunities in information processing. For example it is easy today to send our personal pictures or videos to a remote server (Google Drive, OneDrive …). We can also share this content among the same servers or via social networks and streaming services. However, this personal data is often also available to the service provider, mainly for practical reasons e.g. to configure a video to have the right format regardless of the displayer (smartphone or computer), to share our data with other people, etc. This raises issues of privacy and trust into the service provider. Classical cryptography brings some answers to this kind of issues, yet leaving the problem of handling the encrypted data: e.g., it becomes impossible to reconfigure a video because the provider can no longer “see” it. An alternative solution is “homomorphic encryption”. It is a powerful tool of advanced cryptography which provides the same security as classical cryptography algorithms, but it still allows us to manipulate ciphertexts such their underlying plaintexts are modified. Consequently, it offers a new perspective to service providers since they can continue to process their clients’information without knowing what it contains. This allows them to provide privacy-preserving services and comply with the new General Data Protection Regulation (GDPR). Although it is considered that homomorphic encryption does not have enough maturity due to its large algorithmic complexity, in this thesis, we are trying to show its potential by using it in the context of image and video processing over the encrypted data. In this context, we look at the different algorithms in an image/video encoder (JPEG/H264 and HEVC) and transform them to circuits which can be manipulated by homomorphic encryption schemes. Our main contribution is to propose the first pipeline for an image compression of type JPEG (homomorphic-JPEG) running on end-to-end encrypted pixels. To optimize the management of the encrypted data, we also propose new tools applicable to existing homomorphic encryption schemes over the ring version of lattices. Our approach allows us to maximize the number of slots in some ciphertext and we introduce new functions allowing to handle these slots independently in the encrypted domain. This thesis work also lead to two publications to international conferences as well as the submission of an additional article

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Robson, Eleanor Dezateux. "Improvement and environmental conflict in the northern fens, 1560-1665." Thesis, University of Cambridge, 2019. https://www.repository.cam.ac.uk/handle/1810/290033.

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This thesis examines 'improvement' of wetland commons in early modern England as a contested process of rapid environmental change. As a flagship project of agrarian improvement, drainage sought to alchemise pastoral fen commons into arable enclosed terra firma and promised manifold benefits for crown, commoners, and commonwealth alike. In practice, however, improvement schemes generated friction between the political and fiscal agendas of governors and projectors and local communities' customary ways of knowing and using wetland commons, provoking the most sustained and violent agrarian unrest of the seventeenth century. This thesis situates the first state-led drainage project in England, in the northern fens of Hatfield Level, in the context of the local politics of custom, national legal and political developments, and international movements of capital, expertise, and refugees; all of which intersected to reshape perceptions and management of English wetlands. Drawing on the analytic perspectives of environmental history, this thesis explores divergent ideas and practices generating conflict over the making of private property, reorganisation of flow, and reconfiguration of lived environments. This thesis argues that different 'environing' practices - both mental and material - distinguished what was seen as an ordered or disordered landscape, determined when and how water was understood as a resource or risk, and demarcated different scales and forms of intervention. Rival visions of the fenscape, ways of knowing land and water, and concepts of value and justice were productive of, and produced by, different practices of management, ownership, and use. Drainage disputes therefore crossed different spheres of discourse and action, spanning parliament, courtroom, and commons to bring improvement into dialogue with fen custom and generate a contentious environmental politics. In seven substantive chapters, this thesis investigates how improvement was imagined, legitimised, and enacted; how fen communities experienced and navigated rapid environmental transformation; and how political, social, and spatial boundaries were reforged in the process. By grounding improvement in the early modern fenscape, this thesis reintegrates agency into accounts of inexorable socio-economic change, illuminates ideas at work in social contexts, and deepens understandings of environmental conflict.

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Cheng, Min-Lang, and 鄭敏郎. "The impact of slow steaming on shippers' and forwarders' management strategy." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/66195641918503917428.

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碩士
國立臺灣海洋大學
航運管理學系
101
The purpose of this thesis is to study the impact of the container vessel speed reduction which helps carriers reduce bunker cost and absorb additional capacity on shippers. Average vessel size increased, enhancing alliance co-operation between global carriers, and rising bunker cost are the main issues in the container shipping industry over the past few years. During the recession in 2009, the top 40 ocean container carriers have lost about 15 billion US dollars. The main reason of the heavy lost were attributed to higher bunker cost, over capacity, global economic recession, and low ocean freight. Carriers were taking several necessary measurements to turn to black, such as slow steaming, bunker hedges, choice the most economical routing, and intensify the alliance co-operation mechanism. Slow steaming is the key cost cutting measure not only to reduce the bunker cost but also to absorb the over capacity and reduce the CO2 emission from container ships. All ocean carriers were turning to profit in 2010. On average, global container ships has been cutting speed by 13% in 2011, reducing the sailing speed from 24-25 knots to 21 knots (slow steaming), 18 knots (extra slow steaming) or even 15 knots (super slow steaming). However, slow steaming also has some negative impact to the global supply chain, such as the increase of lead time, safety stock levels, and operating cash flow demand. This study has employed PZB Gap Analysis Model and conducts a survey to know the impact of slow steaming on shippers, NVOCCs and carriers. The research finding has revealed that there is a service quality perception gap between the shippers, NVOCCs, and carriers. Finally this study has used the Importance-Performance Analysis (IPA) technique to find the factors located in the priority quadrant. From ocean carriers’ perspective, bunker cost is found to be the only factor situated in the priority quadrant. From ocean freight forwarders’ and shippers’ perspective, cash flow management, stable and punctual shipping schedule are the three factors located in the priority quadrant. Suggestions and strategies to forwarders and carriers to minimize the impact of slow steaming are finally made.

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Dias, Sílvia de Fátima Gonçalves. "Análise e proposta de alternativas à gestão de slow moving stock." Master's thesis, 2021. http://hdl.handle.net/1822/76155.

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Dissertação de mestrado em Engenharia Industrial
O presente projeto de dissertação foi desenvolvido na empresa Domingos da Silva Teixeira, s.a., que tem como principal atividade a construção civil. O principal objetivo consistiu na melhoria dos processos que dizem respeito à gestão de stocks da empresa, através do desenvolvimento de um procedimento para a redução dos slow movers (materiais de baixa rotação) armazenados. Esta dissertação é composta por duas fases. A primeira fase incide na identificação, classificação e caracterização dos slow movers da empresa através da metodologia de análise de Pareto ou ABC. A segunda fase do projeto, refere-se à identificação dos problemas que existem na empresa, em relação à discrepância entre o stock físico e o informático, rotação do stock e os artigos fora de validade. Esta segunda fase inclui ainda a implementação de um procedimento para reduzir os slow movers armazenados na empresa. Em consequência da quantidade elevada de slow movers em stock, foram criadas estratégias e ações para a redução destes materiais. Neste sentido, é implementado um procedimento que permite à empresa escoar alguns dos seus artigos e desta forma, melhorar a eficiência dos armazéns, libertando mais espaço para que outros artigos possam ser arrumados. Conclui-se que através da implementação deste procedimento, verifica-se posteriormente uma redução de 6,2% no valor total existente em stock. Esta implementação proporciona um controlo mais elevado no inventário e um acréscimo na eficiência dos armazéns.
The present dissertation project was developed at the company Domingos da Silva Teixeira, s.a., whose main activity is civil construction. The main objective is to improve the processes related to the company's stock management, through the development of a procedure for the reduction of stored slow movers (low rotation materials). This dissertation has two phases. The first phase focuses on the identification, classification and characterization of the company's slow movers through the Pareto or ABC analysis methodology. The second phase of the project refers to the identification of problems that exist in the company, in relation to the discrepancy between physical and computer stock, stock rotation and out-of-date items. However, this second phase also includes the implementation of a procedure to reduce the slow movers stored in the company. As a result of the high quantity of slow movers in stock, strategies and actions were created to reduce these materials. In this sense, a procedure was implemented that allowed the company to dispose of some of its articles and thus improve the efficiency of the warehouses, adding more space to store other articles. It is concluded that through the implementation of this procedure, there is subsequently a 6.2% reduction in the total value in stock. This implementation resulted in a higher control of the inventory and an increase in the efficiency of the warehouses.

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Wei, Yu-Hsuan, and 韋宇軒. "The Discussion on the Relationship between the Sustainable Management of Marine Resource and Slow Food : A Case Study of the Chiku Oyster." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/04613739162136785813.

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碩士
真理大學
休閒遊憩事業學系碩士班
100
Due to the excessive depletion of marine resources, the marine environment and ecosystem had been on the verge of collapse, and marine fishery resources face exhausted. Secondly, In order to boost the local fishery economy, the government promotes a series of marine diet-related events, such as the Bluefin Tuna Cultural Festival, Ocean Sunfish Festival, but it obviously lacks long-term consideration in reaching the sustainable management. Recently, the promotional activities of the Slow Food is regarded as one of the strategy of the environmental resources for sustainable development, meanwhile, oyster farming industry has certain value in maintenance of marine environment and fishery economy, so the combination of the concept of the Slow Food and local seafood ingredients is highly worth promoting. Therefore, the purpose of this research is to understand the feasibility of sustainable development on Chiku regional oyster’s resources by following two issues, 1. Explore the attraction of oyster farming industry to tourists; 2. Find out the correlation between Slow Food and sustainable development. This research used Modified Delphi Method (MDM) to construct the dimensions and items of the questionnaire, and purposive sampling to understand the reliability of the questionnaire through factor analysis, reliability analysis. Descriptive Statistics Analysis, correlation analysis, t-test and one-way ANOVA are used for measurement and comprehensive analysis of the 505 valid questionnaires. The results show that 1. The respondents don’t understand the concept of Slow Food very well for the lack of relevant information and there are no Slow Food shops distributed. 2. The oyster farming industry is attractive to the respondents. Though the majority of respondents are not willing to pay money for the interpretation during the tours of experiencing the activity of oyster farming industry, they are still like to taste the representative cuisine used local oysters.3. Slow Food activity has a significant positive correlation with environmental sustainability, and the agreements of respondents are increasing through the understanding of the Slow Food activities, then the sustainable development of oyster farming industry get enhanced. All in all, the spread of Slow Food activity will enhance the cognition of the marine environment and strengthen the importance of sustainable development, then to facilitate the development of oyster farming industry. But it is worth noting that travelers disagree with paying for the narration of the real estate industry because domestic tourists may not realize the essence of pay for the ecotourism. Therefore, how to make tourism more attractive by placing Slow Food activity in the tour plans and combining the education of interpretation is truly a topic worth exploring further.

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Chen, Tzu-yi, and 陳子逸. "A study on Leisure Motivation, Free Time Management, and Leisure Satisfaction in practicing Slow Pitch Softball participants--an example of northern Taiwan." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/68867502879284399171.

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碩士
南華大學
旅遊事業管理學系碩士班
97
The purpose of this study was to explore the discussion Slow Pitch Softball participants to Leisure Motivation, Free Time Management, and Leisure Satisfaction the difference situation. The sample was northern Taiwan Slow Pitch Softball participants. A total of 520 questionnaires were sent out and 482 effective questionnaires were returned. One-way ANOVA and Canonical Correlation were used to analyze the collected data. The findings of this study were as the follows: 1.There were different in the number of days a week in different sports in Leisure Motivation, Free Time Management, and Leisure Satisfaction, there is a difference in Slow Pitch Softball participants - an example of northern Taiwan. 2. After the analysis of IPA, the advantages of northern Taiwan Slow Pitch Softball participants are psychological and social; the disadvantages are physiological and premises equipment. 3. The Leisure Motivation and Leisure Satisfaction presents the positive tendency.4. Free Time Management and Leisure Satisfaction present the positive tendency.

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Silva, Cristiana Manuela Rodrigues da. "Soluções automatizadas para a execução dos produtos de baixa rotação num armazém de abastecimento de lojas de retalho." Master's thesis, 2018. http://hdl.handle.net/1822/56494.

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Dissertação de mestrado em Engenharia de Sistemas
Nos dias de hoje as empresas enfrentam diversos e inúmeros desafios devidos à competitividade existente. Obter melhorias nos processos requer uma regular revisão e avaliação dos mesmos. O processo da preparação de pedidos (picking), é um objetivo bastante relevante, sendo que representa tipicamente o maior custo na gestão do armazém. A presente dissertação foi realizada no âmbito do Mestrado em Engenharia de Sistemas, da Universidade do Minho, em contexto empresarial na empresa Jerónimo Martins, SGPS, S.A., sendo um grupo empresarial português de distribuição alimentar e indústria. O estudo na empresa foi realizado no centro de distribuição da zona Norte, onde pude conhecer os processos logísticos dentro da mesma. No início existiu uma observação atenta do funcionamento do sistema, para assim perceber melhor as necessidades e oportunidades de melhoria nas atividades da empresa. Assim surgiu o principal objetivo do estudo, otimizar a operação de picking para produtos não perecíveis com baixa rotação, slow-movers, sendo que estes produtos dentro da empresa eram pouco analisados. Ao longo do tempo de estudo alguns problemas foram detetados, por exemplo, o tamanho da amostra, a utilização que fazem por parte dos cais, as faltas de entregas feitas pelos fornecedores, a profundidade dos produtos, entre outros. Contudo, encontraram-se oportunidades de melhoria como: alterar o fluxo (JIT para stock, e vice-versa), diminuir o número de entregas, bem como o número de dias, estratégias de picking diferentes e automatizadas. Destas ideias, algumas com maior impacto do que outras ao nível do armazém e da cadeia de abastecimento, surgiram propostas para obter um melhor desempenho do sistema de reaprovisionamento do armazém. O projeto culminou com propostas futuras, para atingir resultados diferentes e melhores em relação aos processos existentes.
Nowadays, companies face numerous challenges due to their existing competitiveness. Getting improvements in processes requires a regular review and evaluation of the same. The process of picking is a very relevant objective, which typically represents the highest cost in warehouse management. The present dissertation was carried out within the framework of the Master of Systems Engineering, University of Minho, in a business context in the company Jerónimo Martins, SGPS, S.A., being a Portuguese business group of food distribution and industry. The study in the company was carried out in the distribution center of the North zone, where I was able to know the logistic processes within the same. At the beginning there was a close observation of system operation, to better understand the needs and opportunities for improvement in the activities of the company. As result, the main objective of the study was to optimize the picking operation for non-perishable products with low rotation, slow-movers, and these products within the company were little analysed. Throughout the study time, some problems were detected, for example, the size of the sample, the use they make of the quays, the lack of deliveries made by the suppliers, the depth of the products, among others. However, improvement opportunities such as: change flow (JIT for stock, and vice versa), decrease the number of deliveries, as well as the number of days, different and automated picking strategies were found. From these proposals, some of which have a greater impact than others at the warehouse and supply chain level, ideas have emerged for a better performance of the warehouse replenishment system. The project culminated in future proposals to achieve different and better results in relation to existing processes.

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Hung, Tseng Ching, and 曾金宏. "A research on Participative Motivation, Free Time Management, and Leisure Satisfaction in Slow Pitch Softball Participants Group of New Taipei City Elementary School Teachers." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/40070658898405342300.

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碩士
聖約翰科技大學
工業工程與管理系碩士在職專班
99
A research on Participative Motivation, Free Time Management, and Leisure Satisfaction in Slow Pitch Softball Participants Group of New Taipei City Elementary School Teachers Abstract This research refers to comprehend the present situation of New Taipei City elementary school teachers’ participative motivation of slow pitch softball, free time management, and leisure satisfaction. It also explores the relation among participative motivation, free time management, and leisure satisfaction. 261 New Taipei City elementary school teachers who participate in slow pitch softball were selected as the samples, and “The questionnaire of elementary school teachers’ participative motivation in slow pitch softball, free time management, and leisure satisfaction.” was applied as the research tool. The data gathered was analyzed by descriptive statistics, independent sample t test, One-way ANOVA and canonical correlation, and Pearson product-moment correlation. The findings are as below: I. Among the elementary school teachers who participate in sports, those who exercise with the frequency of 2~3 days a week were most common. A big portion of slow pitch softball participants were beginners and most of the beginner participants (37.5%) played slow softball for about 1~2 years. The main participative motivation in slow pitch softball is “Social Connections”. ”Skill” stands out from the free time management variables. And “Social Interaction” scores highest among the leisure satisfaction variables. II. Obvious differences exist in participative motivation, free time management and leisure satisfaction in the slow pitch softball participants group of New Taipei City elementary school teachers. (1.) The result shows no obvious difference in participative motivation with various genders, positions, and ages. However, the more frequently participating in the slow pitch softball, the more aggressive the participative motivation is. As well as the higher family monthly income; and the longer experience participating in. (2.) There is no obvious difference in free time management with various genders, positions and family monthly incomes. However, the elementary school teachers who are 30 to 41, more frequently participate in and with longer experience participating in slow softball manage their free time better. (3.) Different genders, positions and participating frequencies do not influence leisure satisfaction. Nevertheless, the teachers who are 41 to 50, have family monthly income between 40001 to 70000, and with longer experience participating in slow softball get higher degree of leisure satisfaction. III. The participative motivation shows positive correlation to free time management and leisure satisfaction. Free time management positively affects the degree of the leisure satisfaction. Besides, the result shows that the participative motivation, free time management, and leisure satisfaction relates one another. The research discovers that to manage elementary school teachers’ free time efficiently, it’s better to encourage them to participate in slow pitch softball sports. This will also help them to raise the degree of leisure satisfaction. Keywords: slow pitch softball, participative motivation, free time management , leisure satisfaction

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Brook, Jacqueline Marie. "Evaluating Innovative Nutrient Management Options and Seasonal Groundwater Recharge Dynamics in an Agricultural Source Water Protection Area." Thesis, 2012. http://hdl.handle.net/10012/7070.

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This thesis presents two interrelated studies that consider nutrient management and seasonal changes in recharge on agricultural lands within the context of source water protection. The research focuses first on the management of the risk to groundwater quality through the implementation of various nutrient management practices and secondly considers the dynamic nature of the transport pathway to the groundwater system associated with seasonal changes in climate and hydrology. The combined results provide insight into several of the key factors influencing the protection of groundwater sources within the agricultural landscape. Field work was completed between 2009 and 2010 on an agricultural field near the City of Woodstock, Ontario. The site is located within a source water protection area; the two-year travel time zone of the Thornton Well Field which represents the primary water supply for the City of Woodstock and which has experienced chronic increases in nitrate concentrations over the last few decades. The wells are completed in glacial overburden consisting of intermingling sand and gravel till aquifers which overly a limestone bedrock aquifer. Agricultural best or beneficial management practices (BMPs) field have been implemented and monitored since 2004. The BMPs were adopted in order to reduce nitrogen losses to the aquifer, and consisted of a reduction in nitrogen fertilizer application rates over a series of agricultural fields located near the well The first study is a one year experiment designed to compare alternative nutrient management practices for corn. Combinations of fertilizer treatments with or without a legume cover crop (red clover) were assessed. The fertilizer treatments studied were: a polymer coated urea (slow-release fertilizer) applied at planting, a conventional urea applied at planting, side-dress treatment of a solution of urea and ammonium nitrate in water containing 28% nitrogen with two different application rates applied in the early summer, and a control. The legume cover crop was incorporated in the soil in the previous fall, and acts as a slow release fertilizer as nitrogen is made available to the following crop as the plants decompose. Treatments were compared based on crop yield, overall economic return, and the potential for nitrate leaching. The potential for nitrate leaching was evaluated with bi-weekly shallow soil core during the growing season, and deep soil cores taken before planting, after harvest and the following spring. The deep cores allowed changes in nitrate storage below the rooting zone to be assessed. The results of this study highlight the importance of timing of fertilizer applications and rate of fertilizer applications. Treatments which provide a delay in the release or application of fertilizer, the polymer-coated urea, the calculator-rate side-dress and the clover cover crop, were found to be advantageous. The polymer-coated urea treatments and side-dress treatments were found to reduce leaching compared to the conventional urea treatment. Treatments with the clover cover crops were not found to reduce crop yields or increase leaching potential, and lower fertilizer costs associated to this practice were found to have a positive economic effect. Plots treated with the high-rate side-dress fertilizer application lost more nitrate to the subsurface compared to the other treatment options, and an economic disadvantage was observed as yields did not compensate for higher fertilizer costs. The study highlights the advantages of the different treatments under study, which may be used to inform policy makers and farmers in the selection of economically and environmentally sustainable nutrient management BMP options. Groundwater monitoring at the site over the years has indentified interesting recharge dynamics, particularly in the vicinity of an ephemeral stream which develops annually during spring and winter melt events in a low lying area of the study site. It was hypothesized that rapid recharge could occur beneath the stream allowing for surface water to quickly reach groundwater, posing a threat to municipal water wells. The current framework of source water protection does not take into account the potential risk posed by this type recharge event. At this field site, rapid infiltration associated with this type of event may pose a risk to drinking water quality due to the proximity of the stream to the pumping wells and the nature of the aquifer. The second study examines rapid groundwater recharge processes beneath the ephemeral stream during the course of a spring melt in 2010. The goals of the study were to quantify recharge at one location beneath the stream and to assess whether temperature variations above the water table can be used as a tracer to reasonably estimate recharge during a short live recharge event. A novel housing for the temperature sensors was designed in order to deploy and position them into gravelly materials within the vadose zone, which reduced the potential for the formation of preferential pathways and permitted the retrieval of the sensors at a later date. Field data were collected during the course of the spring melt period from a network of groundwater monitoring wells and subsurface temperature sensors. Spatial and temporal changes in groundwater geochemistry, hydraulic head and temperature were were used to characterize recharge dynamics at the field site. Recharge beneath a segment of the ephemeral stream was quantified through the numerical analysis of the field data using Hydrus 1-D, a one-dimensional numerical model designed to simulate soil water flow and heat transport in variably saturated porous media. Site specific data were used to create the model domain, provide estimates of physical parameters, and to define initial and time variable boundary conditions. Model parameters were first calibrated by simulating periods where it was expected that soils would be gravity drained with minimal soil water flow, and then further refined by simulating the period when the ephemeral stream was present. A final set of parameters was determined, and the initial gravity drained conditions were re-simulated. The model was able to reproduce field observations under different flow scenarios using the final set of parameters, suggesting that the conceptual model and final model domain representative of the actual field conditions. The successful simulation of the field data sets under the different flow scenarios also increases confidence in the uniqueness of the model results. The model estimated that 0.15 m of recharge occurred beneath the instrumented site during the period between March 9th and March 22nd of 2010 when the ephemeral stream was present. This represents approximately a third of the expected total annual recharge for this location. Regional changes in hydraulic head, groundwater temperature and groundwater chemistry provided additional insight into the dynamic nature of the recharge process during the spring meld period and further illustrated the spatial variability of the aquifers’ response to the stream. The study found that the use of temperature as a tracer provided useful and quantifiable insight into recharge phenomena. The results of this study suggest that high rates of rapid recharge occur beneath the ephemeral stream, and are spatially variable. This type of focused infiltration that occurs during the spring melt may represent a risk to municipal water quality if the infiltrating waters are carrying contaminants.

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Cunha, Joana Filipa da Silva. "Otimização da gestão de inventário de baixa rotação numa empresa de comércio a retalho." Master's thesis, 2021. http://hdl.handle.net/1822/72408.

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Dissertação de mestrado em Engenharia Industrial (área de especialização de Logística e Distribuição)
A presente dissertação, realizada no âmbito do Mestrado em Engenharia Industrial, do ramo de especialização em Logística e Distribuição, descreve o trabalho desenvolvido relativamente à otimização da gestão de inventário de baixa rotação na Leroy Merlin de Braga. A problemática abordada surgiu da constatação que o armazém de Braga já não possui espaço suficiente para alocar o material que recebe diariamente, necessário para responder às necessidades dos clientes. O projeto foca-se sobre a única secção da loja que, devido ao excesso de stock armazenado, possui um corredor para alocação de artigos – a secção de sanitários. Para o diagnóstico de problemas, realizou-se uma análise ao inventário total da secção de sanitários, relativamente à diversidade de artigos, às unidades e ao valor em stock. Posteriormente, a análise focou-se sobre o stock armazenado, mais concretamente sobre os artigos de baixa rotação e sem vendas. Com o propósito de solucionar os problemas encontrados e cumprir com os objetivos propostos, procedeu-se ao desenvolvimento de alguns planos de ação para o escoamento dos artigos de baixa rotação e dos artigos sem vendas. A criação de um modelo de controlo de inventário e a exposição de artigos que apenas se encontravam armazenados constituem algumas das medidas implementadas. O modelo de controlo de inventário permite a análise do inventário total da loja e apresenta os planos de ação mais adequados para o escoamento de artigos de baixa rotação. Os planos de ação foram definidos de acordo com a especificidade de cada artigo, relativamente à cobertura de stock em dias, à gama e tipologia. As medidas implementadas permitiram o escoamento de 114 unidades de stock, das quais 95 unidades não possuíam histórico de venda. Com a utilização do modelo criado, pretende-se evitar o surgimento de novos artigos de baixa rotação e, com o escoamento dos artigos de baixa rotação existentes através da aplicação do plano de ação correspondente, fazer um maior proveito do espaço de armazenamento. A prática de uma gestão de inventário rigorosa, conjuntamente com a utilização de um sistema de informação frequentemente atualizado, permitirá que empresa consiga responder às necessidades dos clientes com eficácia e, consequentemente, manter a sua competitividade no mercado.
The present dissertation, carried out in the framework of the Master’s degree in Industrial Engineering, in the field of specialization of Logistics and Distribution, describes all the work developed in the scope of the optimization of slow moving inventory management at Leroy Merlin in Braga. The problem addressed arose from the perception that Braga’s warehouse no longer has enough space to allocate the material it receives daily, necessary to meet the customer needs. The project focuses on the only section of the store that, due to excesso stock stored, has a corridor for the allocation of articles – the sanitary section. For the diagnosis of problems, an analysis was carried out on the total inventory of the sanitary section, in relation to the diversity of articles, units and value in stock. Subsequently, the analysis focused on the warehouse’s inventory, more specifically on the slow moving inventory and the articles without historical sales data. In order to solve the problems identified and meet the proposed objectives, some action plans were developed. The creation of a list of articles without historical sales data and the display in the store of articles that were only allocated in the warehouse are some of the measures implemented. Additionally, an inventory control model was created. This model allows the analysis of the store's total inventory and presents the most appropriate action plan for the slow moving inventory. The plans were defined according to the specificity of each article, regarding the stock coverage (in days), range, and typology. The measures implemented allowed the disposal of 114 stock units, of which 95 units had no historical sales data. With the use of the created model, it is intended that to avoid the appearance of new slow moving articles and, with the disposal of the existing slow moving articles through the application of the corresponding action plan, make greater use of the warehouse space. The practise of a rigorous inventory management, combined with the use of a frequently updated information system, will allow the company to respond to the needs of customers effectively and, consequently, maintain its competitiveness in the market.

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Tsyr, Wu Ching, and 吳清慈. "Developing an intelligent container slot management information system." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/38414682259506555054.

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Peixoto, Armando Silvestre Loureiro. "Delivery Time Slot Management Methods in Online Retail." Dissertação, 2019. https://hdl.handle.net/10216/121392.

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During recent years, e-commerce and the convenience that it carries has allured consumers to opt for this service. Nonetheless, retailers are concerned about the narrow profitability margins that this activity yield, leading them to try to optimize their delivery processes. For the comfort of the customer, e-grocers normally practices attended home delivery (AHD). This implies that the client has to be at home to receive their package, hence, the delivery hours are an important feature of the service provided. Time slot management is necessary to maintain a good balance between the client impression towards the service and delivery fulfillment. To optimize the distribution cost, customers are presented with time slots to choose from when making a purchase, influencing the company's delivery schedule. Thanks to the existence of this choice, we can try to influence customers to choose a certain time slot, possibly resulting in a more optimized and cost-efficient delivery process. The selection of these slots can follow a dynamic slotting and/or dynamic pricing strategy. This dissertation will focus on a dynamic slotting strategy, investigating the benefits that different assumptions could bring, for instance, that the customer can be flexible with the delivery day.

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Peixoto, Armando Silvestre Loureiro. "Delivery Time Slot Management Methods in Online Retail." Master's thesis, 2019. https://hdl.handle.net/10216/121392.

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During recent years, e-commerce and the convenience that it carries has allured consumers to opt for this service. Nonetheless, retailers are concerned about the narrow profitability margins that this activity yield, leading them to try to optimize their delivery processes. For the comfort of the customer, e-grocers normally practices attended home delivery (AHD). This implies that the client has to be at home to receive their package, hence, the delivery hours are an important feature of the service provided. Time slot management is necessary to maintain a good balance between the client impression towards the service and delivery fulfillment. To optimize the distribution cost, customers are presented with time slots to choose from when making a purchase, influencing the company's delivery schedule. Thanks to the existence of this choice, we can try to influence customers to choose a certain time slot, possibly resulting in a more optimized and cost-efficient delivery process. The selection of these slots can follow a dynamic slotting and/or dynamic pricing strategy. This dissertation will focus on a dynamic slotting strategy, investigating the benefits that different assumptions could bring, for instance, that the customer can be flexible with the delivery day.

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Carvalho, Luís Miguel Vaz de. "Tactical Time Slot Management Under Fulfillment Considerations in E-Grocery." Master's thesis, 2019. https://hdl.handle.net/10216/122282.

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Hong, Tzu-Yen, and 洪子晏. "A Simulation-based Auction Model for Attended Home Delivery Time Slot Management." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/7my24g.

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碩士
國立東華大學
運籌管理研究所
102
With the high utilization of information technology nowadays, the diversity of consumed styles are wider than before. Instead of shopping in the physical store, people are getting used to shop in the online market and receive their purchased products at home now. The home delivery logistics has already become the powerful backing force of companies because of the wide range of applications in each industry. In the investigation made by the marketing research consultant company in 2011, the most attractive policy for the home delivery companies to attract the customers is to provide the service of “the customer can choose a specific arrival time slot ”. However, the biggest obstacle for the home delivery companies is the unbalance of the peak and off peak time slots. In the peak time slot, the high demand may result in the delivering delay of the products. Conversely, the low demand in the off peak time slot may result in the idol cost. In our study, we try to investigate the management of home delivery service system integrated both the pricing and the auction mechanism. Through providing the customers to choose a specific time slot, the home delivery service providers can shift peak demand off peak time slot, enhance the utilization of the truck, decrease the redelivery cost, and decrease the average waiting time of the customers at the same time. Through the pricing model, the logistics providers can determine the posted price and the minimum acceptable price of each opening time slot. We can also assign the time slot to the bidders who will maximize the revenue through the auction model. In our study, we will also investigate the performance evaluation of different auction mechanisms. By adjusting the variables such as posted price, the minimum acceptable price, and the capacity of each time slot, we look forward to observing the reasons which will impact the value of expect revenue. On the other hand, we will also analyze the effect of reference price in customer’ behaviors on the shipping price that customers are willing to pay (anchoring effect). The relationship between the ratio of affected customer and the value of revenue is also investigated by sensitivity analysis.

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Chen, Yu-Jie, and 陳毓潔. "A Dynamic Pricing Model for Time Slot Management in Attended Home Delivery Logistics." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/64216079546088398670.

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碩士
國立東華大學
運籌管理研究所
101
Over the past decade, online shopping has grown in popularity with customers and grocers alike. Offering customers the choice of delivery time slots is an emerging business strategy in attended home delivery service since it has potential to increase service level and reduce the risk of delivery failure. Although offering this delivery service can provide customers more conveniences, maintaining the efficiency and profitability of this service has been recognized as one of the great challenges faced by system operators. In this paper, we propose dynamic pricing models, with the objective of maximizing the revenue of a provider of attended home deliveries, while also shifting peak demand toward off-peak time slots, increasing the utilization of trucks, reducing the potential redelivery costs, and improving the matches between customers’ preferred delivery time/price and carriers’ desirable time slots/charge fees through a specific bidding mechanism. The models are formulated to determine the optimal posted price, the minimum acceptable bid price for each biddable time slot and the assignment of time slots to customers. The study starts from a typical dynamic pricing model with three kinds of customers (i.e. price-taker, bidders, and leave-without-pay) and then considers heterogeneous characteristics of peak and off-peak time slots. Some sensitivity analyses are presented to demonstrate that price movement is efficient in response to changed conditions such as remaining time slots and different demand rates.

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Ribeiro, Nuno Antunes. "Airport capacity management: towards a slot allocation modelling approach compliant with IATA rules." Doctoral thesis, 2019. http://hdl.handle.net/10316/87612.

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Tese de Doutoramento em Sistemas de Transporte, apresentada ao Departamento de Engenharia Civil da Faculdade de Ciências e Tecnologia da Universidade de Coimbra
Air traffic demand has grown to exceed available capacity during extended parts of each day at many of the busiest airports in the world. Absent opportunities for capacity expansion, this may require the use of demand management measures to restore the balance between scheduled traffic and available capacity. The main demand management mechanism in use today is the administrative slot allocation process operated by the International Air Transport Association (IATA), which is in place at the great majority of the busiest airports outside the United States. At these airports, airlines need to be assigned slots by a slot coordinator to schedule their flights. Slot allocation is driven by a set of rules and priorities specified in the IATA Worldwide Slot Guidelines (WSG). These rules introduce coupling constraints across the allocation of slots at multiple times of the day and multiple days of the year, resulting in a highly complex combinatorial problem that carries enormous weight for airlines, airports and passengers. In recent years, integer programming models have been proposed to support slot allocation by minimizing deviations from the airlines’ requests. However, due to the problem’s complexity, these models have been only successfully implemented at small size airports (up to 50,000 flights per year). In this thesis, we develop an original modelling approach aimed to advance existing slot allocation tools and procedures at the largest airports in the world. For that purpose, we formulate a novel integer programing model of slot allocation fully compliant with the WSG rules. The model – named Priority-based Slot Allocation Model (PSAM) – develops an original and efficient mathematical formulation that enables its implementation using exact optimization methods at airports at least with twice the size as previously considered. In order to solve the slot allocation problem at the busiest airports in the world, we also develop an algorithmic approach based on large-scale neighborhood search heuristics. The proposed algorithm combines a constructive heuristic to provide an initial feasible solution in short computational times, and an improvement heuristic that iteratively re-optimizes slot allocation by subdividing the slot requests into smaller subsets. Experimental results show that the algorithm proposed can provide optimal, or near-optimal solutions, in a few hours of computation in instances where direct implementation of PSAM with commercial solvers does not terminate after several days of computation. The modelling approach proposed in this dissertation was implemented at three Portuguese airports, a small one (Madeira), a mid-size one (Porto) and a large one (Lisbon), using highly detailed data on airline slot requests and airport capacity constraints. Results suggest that its implementation in support of slot allocation at major slot-coordinated airports worldwide can result in flight schedules that match better airlines’ requests and passenger demand. Equally important, the modelling approach developed in this dissertation can also be used to quantify the sensitivity of slot allocation decisions to the various priorities and requirements specified in the WSG. This allowed us to evaluate the impact of potential changes in the current slot allocation rules and procedures. Results obtained from many sensitivity analyses performed using PSAM show that adding even limited flexibility to the WSG can, on its own, bring considerable benefits in the short term to the slot allocation process.
A procura pelo tráfego aéreo tem aumentado nos aeroportos mais movimentados do mundo, ao ponto de superar a capacidade neles disponível durante longos períodos do dia. Na ausência de possibilidades de expansão, é essencial recorrer a medidas de gestão de procura para restabelecer o equilíbrio entre o número de voos calendarizados e a capacidade disponível no aeroporto. A principal medida de gestão de procura utilizada consiste no processo de atribuição de slots da Associação Internacional de Transportes Aéreos (IATA). De acordo com este processo, qualquer companhia aérea que pretenda operar um voo num aeroporto coordenado terá de obter antecipadamente uma permissão para a hora em que deseja que a aterragem ou descolagem do voo tenha lugar. O processo de atribuição de slots é regido por um conjunto de regras e prioridades que estão definidas nas IATA Worldwide Slot Guidelines (WSG). Estas regras introduzem um conjunto de restrições que tornam o problema de atribuição de slots bastante complexo. Nos últimos anos, vários modelos de programação inteira foram desenvolvidos com o intuito de auxiliar os coordenadores de slots a otimizar as suas decisões. No entanto, devido à complexidade do problema, estes modelos apenas podem ser eficazmente implementados em aeroportos de pequenas dimensões (até 50,000 voos por ano). Nesta tese é desenvolvida uma abordagem de modelação destinada a melhorar os procedimentos utilizados na atribuição de slots em aeroportos de grandes dimensões. Com esse propósito, é formulado um modelo de programação inteira de atribuição de slots totalmente compatível com as regras especificadas nas WSG. O modelo, denominado Priority-based Slot Allocation Model (PSAM), utiliza uma formulação matemática eficiente que permite a respetiva implementação através de métodos exatos de otimização em aeroportos com o dobro (ou mesmo mais) das dimensões previamente consideradas na literatura. No sentido de resolver o problema da atribuição de slots em aeroportos de ainda maiores dimensões é também desenvolvido um algoritmo aproximado que se baseia em heurísticas de large-scale neighborhood search. O algoritmo proposto combina uma heurística construtiva, utilizada para gerar solução iniciais admissíveis, e uma heurística de melhoramento, utilizada para melhorar essas soluções iterativamente. Os resultados experimentais da aplicação destas heurísticas mostram que o algoritmo proposto fornece, em poucas horas de computação, soluções ótimas ou muito próximas das ótimas quando a implementação direta de PSAM utilizando software comercial de otimização não fornece a solução ótima após vários dias de computação. A abordagem de modelação proposta nesta dissertação foi implementada em três aeroportos portugueses, nomeadamente um aeroporto de pequena dimensão (Madeira), um de média dimensão (Porto) e um de grande dimensão (Lisboa). Os estudos de caso analisados foram sustentados por dados detalhados referentes aos pedidos de slots feitos pelas companhias aéreas para esses aeroportos. Os resultados obtidos sugerem que a abordagem de modelação desenvolvida nesta tese pode auxiliar o coordenador de slots a tomar melhores decisões, nomeadamente encontrando soluções que se aproximam mais dos interesses das companhias aéreas e dos passageiros. Igualmente importante, a abordagem de modelação proposta nesta dissertação pode ser utilizada com o intuito de avaliar o impacto de pequenas alterações às regras existentes de atribuição de slots especificadas nas WSG. Resultados obtidos através de várias análises de sensibilidade realizadas usando o PSAM mostram que mesmo pequenas alterações podem, por si só, trazer no curto prazo consideráveis benefícios ao processo de atribuição de slots.

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Chen, Hsiao-Yi, and 陳曉儀. "Study on Liner Carrier Revenue Management-The Integration of Slot Allocation and Container Routing Analysis." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/28288307209185136874.

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Lee, Hsu-Yao-Hua, and 李許耀華. "The Characteristic of Operation and Management for the Water Treatment Plant with an On-Slot Reservoir." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/523dz9.

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碩士
崑山科技大學
環境工程研究所
97
In Taiwan’s natural water of drinking water source frequently polluted due a rainfall, storm and human behavior. That was always caused a high turbidity of raw-water and pollutants more increases in nature water. As the result, a damage purification efficiency and dinking water quality of water treatment plant was beginning concerned. Taiwan’s government for accuracy a safety and steady nature water sources usually used new site, development and enhance as high performance increasing the purification efficiency and supplying water quality for WTP in Taiwan, but it was insufficiency and expensive. Because all purification units of WTP was impossible due to a processes deviation, the resulet of operation was not sure match function of design. The other word, this fact illustrated that we should pay attention to the cause of the variation of operation and management of water treatment plant (WTP). On this study, resulting clearly indicate that processes deviation would induce a variation of purification efficiency and effluent turbidity of WTP. In which of decreasing the purification efficiency has occurred a risk that was about variation of raw water turbidity frequency. Besides, the turbidity removal fraction ratio for purification units of WTP have been found that make the turbidity removal contribution was complementary for unsteady operation of purification units.

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Dissertations / Theses on the topic 'Slow management'

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