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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
531

Four Essays on Language Competition and Dynamic Language Policy Evaluation

Templin, Torsten 25 September 2019 (has links)
Diese Dissertation beschäftigt sich mit der Evaluation von Sprachpolitiken mit Hilfe von Sprachdynamik Modellen. Da sprachliche Diversität ein zentrales Merkmal moderner Gesellschaften darstellt, müssen Staaten und Administrationen Sprachpolitiken sorgfältig gestalten und evaluieren. Mögliche Effekte, Nutzen und Kosten von Politiken müssen bewertet und gegeneinander abgewogen werden. Eine wichtige Eigenschaft von Sprachpolitiken ist dabei, dass sich die Anzahl derer, die von ihnen profitieren, sowie deren Kosten über die Zeit stark verändern können. Um dies zu berücksichtigen, präsentiert die Dissertation eine Kombination aus klassischen Politikanalyse Werkzeugen und neuen Sprachdynamik Modellen. Im Gegensatz zu bereits existierenden Modellen, können in den neu entwickelten Modellen Parameter aus empirischen Daten geschätzt werden. Dies ist eine Voraussetzung, um langfristige Effekte von Politiken realistisch abbilden zu können. Die Dissertation besteht aus vier eigenständigen Aufsätzen. Im ersten Aufsatz wird mit einem abstrakten Modell gezeigt, dass es für einen Staat optimal sein kann die Minderheitensprache in Form von Bilingualität am Leben zu erhalten. In den folgenden beiden Aufsätzen werden realistischere Modelle entwickelt und damit zwei empirische Fälle analysiert. Im letzten Aufsatz werden Erweiterungen der vorherigen Modelle auf den Fall multipler Minderheitensprachen vorgestellt. / This thesis deals with language policy evaluation from a language dynamics modeling perspective. As linguistic diversity is an essential feature of most modern societies, states and administrations have to thoroughly design and analyze language policies. Potential effects, benefits and costs have to be assessed and weighted against one another. A pivotal characteristic of language policies is that the numbers of their beneficiaries and costs can change dramatically over time. To account for these changes, the thesis proposes a combination of traditional policy evaluation techniques with well designed language dynamics models. In contrast to previous models in the literature, the thesis proposes and analyzes models based on parameters obtainable from empirical data. It is argued that this is a prerequisite to analyze the long term effects of policies in a realistic fashion. This thesis consists of four self-contained essays. In the first essay we show with the help of an abstract model that it can be optimal for the state to keep a minority language alive in the form of bilingualism. In the next two essays more realistic models are developed and applied to the empirical cases. In the last essay extensions of the previous models to the case of several minority languages are presented.
532

Mehrebenen-Evaluation von Maßnahmen der betrieblichen Gesundheitsförderung

Fritz, Sigrun 01 December 2004 (has links)
Die Dissertation beschreibt am Beispiel einer Längsschnittstudie in der Papierindustrie, wie Effekte von Maßnahmen der betrieblichen Gesundheitsförderung in geschätzten ökonomischen Nutzen übertragen werden können. Ausgangspunkt der Untersuchung ist das Variablen-Modell nach Locke und Latham (1990). Darauf aufbauend wurden geeignete Indikatoren und Messinstrumente ausgewählt und in mehreren Voruntersuchungen überprüft. Hauptinstrument ist ein Fragebogen, der im quasiexperimentellen Design zur Ist-Analyse und nach Umsetzung der Maßnahmen eingesetzt wurde. An der ersten Befragung im Oktober 2000 nahmen 320 Gewerbliche und Angestellte des Unternehmens (Rücklauf 89%), an der zweiten drei Jahre später 402 Mitarbeiter (Rücklauf 91%) teil. Für den Längsschnitt standen die Fragebögen von 118 Mitarbeitern zur Verfügung. Neben den Fragebogendaten wurden personbezogene Daten zum Krankenstand erhoben, die auf freiwilliger Basis mit den Fragebogendaten verknüpft wurden, worauf sich 71% der im Jahr 2000 Befragten und 80% der im Jahr 2003 Befragten einlassen konnten. Zur Absicherung der Validität kamen weitere Untersuchungsmethoden zum Einsatz: für 19 Tätigkeiten wurde eine objektive arbeitspsychologische Tätigkeitsanalyse (Pohlandt, Schulze, Jordan & Richter, 2002) durchgeführt, die beteiligten Bereiche wurden in einem Rankingverfahren durch betriebliche Experten eingeschätzt, die organisationale Einbindung der betrieblichen Gesundheitsförderung wurde zu beiden Untersuchungszeitpunkten mit Hilfe des Fragebogens von Breucker (Prävention online, 2000) erfasst, es fanden 22 strukturierte Interviews mit den Beschäftigten zur Einschätzung der durchgeführten Maßnahmen statt. Die Ergebnisse der ersten Mitarbeiterbefragung wurden zurückgemeldet, diskutiert und zu 12 Maßnahmen verdichtet. Diese 12 Maßnahmen wurden in die Zweitbefragung mit aufgenommen, wobei die aktive Beteiligung an ihnen und die Zufriedenheit mit ihrer Umsetzung eingeschätzt werden sollten. Zur Ermittlung der Effizienz wurden eine erweiterte Kosten-Nutzen-Analyse (nach Schmidt, Hunter & Pearlman, 1982) und eine Kosten-Nutzwert-Analyse (nach Rinza & Schmitz, 1992) durchgeführt. Fast alle im Fragebogen erfassten Variablen hatten sich zwischen der ersten und zweiten Befragung signifikant verbessert (Arbeitsintensität, Tätigkeitsspielraum, Motivationspotenzial der Tätigkeit, soziale Unterstützung, sozialen Stressoren, Commitment, Arbeitszufriedenheit, allgemeines Befinden, psychosomatische Beschwerden). Nicht signifikant waren die Änderungen beim (multimodal beeinflussten) Krankenstand, sowie bei der Einschätzung der Führung. Bezüglich der Effektstärke konnte bei 9 der 12 Maßnahmen mindestens ein positiver Unterscheidungseffekt aufgezeigt werden. Bei der Ermittlung des (subjektiv erlebten) Nutzwertes der Maßnahmen kamen alle 12 Maßnahmen in den positiven Bereich. Mit der Kosten-Nutzen-Analyse wurde ein positives Kosten-Nutzen-Verhältnis für 6 der 9 verbleibenden Maßnahmen (zwischen 1:71 und 1:1,5) ermittelt. Diese Ergebnisse wurden kritisch hinterfragt und durch Einbeziehung von Diskontierung, spezifischen Effizienzkriterien, Sensitivitätsanalysen und Worst-Case-Berechnung relativiert (vgl. Anforderungen nach Drummond, O´Brien, Stoddart & Torrance, 1987/1997). Im Vergleich zur Kosten-Nutzen-Analyse wurden bei der Kosten-Nutzwert-Analyse deutlich andere Rangreihen ermittelt. Die kritische Gesamtschau der Ergebnisse ermöglicht spezifische Empfehlungen für fünf Maßnahmengruppen. Es zeigte sich, dass die gemeinsame Erörterung von Kosten-Nutzen-Analyse und Nutzwert zusätzliche und bisher nicht erfasste Aspekte beim Umgang mit den Maßnahmen eröffnet. / The thesis illustrates a longitudinal study in the paper industry. It shows how effects resulting from measures of occupational health promotion may be translated into an estimated economic advantage. The starting point of the study is the high performance cycle (Locke & Latham: 1990). Proceeding from that, appropriate indicators and measuring instruments were selected and tested in several pre-studies. The main instrument is a questionnaire, used in a comparative design before and after the translation of the measures into practice. 320 white- and blue-collar workers took part in the first survey in October 2000 (response rate 89%), whereas 402 workers participated in the second survey which was conducted three years later (response rate 91%). After all, complete data sets for the longitudinal analysis were available from 118 participants. Apart from that personal data concerning absenteeism were used, which were then connected to the questionnaire data on a voluntary basis. Whereas in 2000, in the first survey, 71% of the participants agreed to the connection of their personal data with the questionnaire, 80% agreed to it in the second survey, in 2003. To guarantee the questionnaire?s validity an array of additional methods was used: an objective occupational job analysis (Pohlandt, Schulze, Jordan & Richter, 2002) of 19 different occupations was carried out and the company?s experts evaluated the branches involved by ranking. Furthermore the organizational embedding of occupational health promotion measures was investigated in both surveys with the help of Breucker?s questionnaire (Prevention online, 2000) and additionally 22 structured interviews with the employees took place in order to evaluate the acceptance of the measures conducted. The results of the first employee survey were reported back, discussed and condensed into 12 measures. These 12 measures were then included in the second survey when the employees? active participation in the measures? implementation and their satisfaction with the measures? effects should be evaluated. To determine the measures? actual efficiency an extended cost-benefit-analysis (with reference to Schmidt, Hunter & Pearlman: 1982) and a cost-utility-analysis (with reference to Rinza & Schmitz: 1992) were conducted. Nearly all variables investigated in the questionnaire had significantly improved between the first and the second survey (indicators of job demands, occupational scope, motivational potential of occupation, social support, social stressors, commitment, job satisfaction, well-being, psychosomatic complaints). Changes in (multi-modally influenced) absenteeism and in the evaluation of the management?s style of leadership were not significant. Referring to the effects? impact 9 out of 12 measures proved to be positively significant in at least one criterion, whereas referring to (subjectively felt) utility all 12 measures turned out to be positively significant. In six of the remaining nine measures the cost-benefit-analysis resulted in a positive cost-benefit-relation (between 1:71 and 1:1,5). These results were critically discussed and taking into account discounting, specific result-criteria, sensitivity analyses and worst case assessment (see quality principles by Drummond, O´Brien, Stoddart & Torrance, 1987/1997) finally adjusted. Comparing the cost-benefit and cost-utility analyses resulted in significantly different rankings. The critical overall view allows for specific recommendations for five measure-groups. Finally, the joint discussion of the cost-benefit analysis and utility turned out to open up additional aspects of how to conduct the measures in future, which have not been described so far.
533

Hodnocení investičního záměru výstavby mateřské školy / Evaluation of Investment Plan of Kindergarten Construction

Janusová, Barbora Unknown Date (has links)
The diploma thesis focuses on the evaluation of investment plan for the kindergarten construction, what is a public investment project. The first part of the thesis is the theoretical part, which discusses the theoretical basis of investments, investment plan, investment and public projects, investment decision - making and strategic planning. The theory part also describes the feasibility study and methods of project evaluation. Within the methods of project evaluation, the thesis deals with the Cost – Benefit analysis. The practical part of the thesis evaluates the investment plan named “Nástavba a přístavba mateřské školy Elišky Krásnohorské 15, Brno “, where is also performed the sensitivity analysis and qualitative risk analysis. The evaluation of investment plan for the kindergarten construction is performed in the eCBA application.
534

Technicko-ekonomické posouzení projektů čistíren odpadních vod a jejich dopadu na životní prostředí / Technical and economic assessment of projects of wastewater treatment plants and their impact on the environment

Turková, Jiřina Unknown Date (has links)
The doctoral thesis deals with the issue of evaluating of technical-economic efficiency of wastewater treatment plant projects. Same as most public benefit projects, the main reason for implementation is the societal benefit of the company, not the impact on the investor. The literature review provides an overview of the most commonly used methods of environmental impact assessment, which differ in both the difficulty of processing and in the structure of input and output information. In accordance with the European legislation, the Cost Benefit Analysis (CBA) is applied to a selected sample of waste water treatment plants, in its economic part, the standardly assessed societal impacts are extended by other possible benefits associated with the implementation of the project implementation. The main output of the thesis is the quantification of the increment to the societal benefit of the project, which is set to the difference between the economic net present value of the investment and the standard and individually designed socio-economic impacts. As an alternative to the traditional approach, the thesis also simulates the Data Envelopment Analysis (DEA), method is based on multi-criteria evaluation shows the technical efficiency of the sewage treatment plant sample and thus serves as a very effective tool in managerial decision-making.
535

Valorising Organic Waste using the Black Soldier Fly (Hermetia illucens), in Ghana

Joly, Gabrielle January 2018 (has links)
Ghana as a rapidly growing and urbanizing middle-income country is facing a number of challenges, including (1) implementing a sanitary, environmental-friendly, and economically-sound waste management system; (2) increasing its agricultural productivity in a sustainable way to meet the growing domestic food demand; and (3) providing livelihood opportunities in both rural and urban areas. Using the black soldier fly (BSF), a particularly beneficial insect, to locally and cost-effectively valorise abundant, high-impacting, and nutrient rich organic waste streams, such as food waste (FW) and faecal sludge (FS), into affordable and sustainable farming inputs like organic fertilizer and animal feed products, could tackle all these challenges at the same time. Therefore, this study aimed at (1) providing a comprehensive overview of BSF technology; (2) investigating the technical feasibility of valorising food waste and faecal sludge using a low-tech BSF bioconversion system; and (3) assessing the economic viability of such system in the Ghanaian context. First, through an extensive literature review and field visits of BSF units, the different dimensions of the BSF technology were discussed, BSF waste treatment method was compared to other options for organic waste valorisation, case studies of implementation were documented, the status of the research was highlighted, and research gaps were identified. In a second step, a 10-week field work consisting of establishing a BSF colony and recording rearing performance in the one hand, and running two waste treatment trials using a low-tech BSF system on the other hand, enabled demonstrating the technical feasibility of co-digesting FW and FS with the BSF, as well as artificially rearing the BSF in Ghana using a low-tech system. However, further research is needed to characterize the bioconversion products, determine the optimal FW/FS ratio, and optimize the rearing performance of the system. Finally, a costbenefit analysis was conducted to compare three scenarios: (1) co-composting FW and FS into fertilizer; (2) co-digesting FW and FS with BSF into only animal feed; and (3) co-digesting FW and FS with BSF into both animal feed and fertilizer. By building financial models for each scenario and performing a sensitivity analysis, it was established that, in the Ghanaian context, scenario (3) was the most likely to be viable, as well as the most profitable, followed by scenario (1).  On the other hand, scenario (2) was associated with a much lower likelihood to be viable. Eventually, the choice of the optimal valorisation option for FW and FS should consider the local context and priorities. / Ghana, ett snabbväxande medelinkomstland med kraftig urbanisering, står inför ett antal utmaningar, bland annat att (1) införa ett sanitärt, miljövänligt och ekonomiskt avfallshanteringssystem; (2) öka sin jordbruksproduktivitet för att möta den växande inhemska efterfrågan på livsmedel på ett hållbart sätt, och (3) erbjuda möjligheter till försörjning både på landsbygden och i städerna. Genom att använda den svarta soldatflugan (SSF), en särskilt fördelaktig insekt, för att lokalt omvandla rikligt förekommande och näringsrika organiska avfallsströmmar, såsom matavfall (MA) och fekalslam (FS) till prisvärda och hållbara jordbruksinsatsvaror, såsom organiskt gödselmedel och djurfoder, skulle man på ett kostnadseffektivt sätt kunna ta itu med alla dessa utmaningar samtidigt. Därför syftade denna studie till (1) att ge en övergripande översikt över SSF-teknik; (2) undersöka den tekniska möjligheten att skapa värdefulla produkter av matavfall och fekalslam med hjälp av ett biotekniskt system med lågteknologisk SSF i Ghana; och (3) bedöma det ekonomiska systemets bärkraft. Först, baserat på en omfattande litteraturstudie och fältbesök, diskuterades SSF-teknikens olika dimensioner, jämfördes SSF-avfallshanteringsmetoden med andra alternativ för organiska avfallsvalorisationer, dokumenterades fallstudier, redovisades forskningsläget och identifierades kunskapsluckor. I ett andra steg genomfördes ett 10 veckors fältarbete som bestod dels av att etablera en SSF-koloni och dokumentera uppfödningsprestanda, dels att göra två avfallsbehandlingsförsök med hjälp av ett SSF-system med lågteknologi. Därigenom visades att det är tekniskt möjligt att sambehandla MA och FS med SSF, liksom att föda upp SSF i Ghana med hjälp av ett lågteknologiskt system. Det behövs dock ytterligare forskning för att karakterisera slutprodukterna, bestämma det optimala MA/FS-förhållandet och optimera systemets uppfödningsprestanda. Slutligen genomfördes en kostnadsnyttoanalys för att jämföra tre scenarier: (1) kompostering av MA och FS till gödselmedel; (2) sambehandling av MA och FS med SSF till endast djurfoder; och (3) sambehandling av MA och FS med SSF till både djurfoder och gödningsmedel. Genom att bygga modeller för varje scenario och genomföra en känslighetsanalys fastställdes att för Ghana var scenario (3) mest sannolikt livskraftigt, liksom det mest lönsamma, följt av scenario (1). Scenario (2) förknippat med en mycket lägre sannolikhet att vara genomförbart. Till sist bör valet av det optimala behandlingsalternativet för MA och FS ta hänsyn till lokala förhållanden. / Le Ghana, pays en voie de développement connaissant une forte croissance et urbanisation, est confronté à un certain nombre de défis, parmi lesquels (1) la mise en place d’un système de gestion des déchets performant du point de vue sanitaire, environnemental, et économique ; (2) l’augmentation durable de sa productivité agricole afin de répondre à la demande alimentaire croissante dans le pays ; et (3) la création d’opportunités économiques pour ses populations rurales et urbaines. Utiliser la mouche soldat noire (MSN), un insecte particulièrement bénéfique, pour valoriser localement et à moindre coût des déchets organiques abondants, riches en nutriments, et responsables d’importants dommages sanitaires et environnementaux, tels que les déchets alimentaires (DA) et boues de vidange (BV), en intrants agricoles écologiques et bon marché, comme des produits alimentaires pour animaux ou de l’engrais organique, contribuerait à relever tous ces défis à la fois. Ainsi, cette étude visait à (1) réaliser un état de l’art de la technologie liée à la MSN ; (2) étudier la faisabilité technique de valoriser les DA et BV à l’aide d’un system à faible technologie reposant sur la MSN ; (2) analyser la viabilité économique d’un tel system dans le contexte Ghanéen.  Dans un premier temps, un examen approfondi de la littérature scientifique et des visites d’unités de recyclage utilisant la MSN ont permis d’analyser les différentes dimensions de cette technologie, de la comparer à d’autres options de valorisation pour les déchets organiques, de présenter des études de cas, de donner un aperçu de l’état actuel de la recherche, ainsi que de d’identifier les principales lacunes et besoins en matière de recherche. Dans un second temps, dans le cadre d’une étude de terrain réalisée sur une période de dix semaines, un système d’élevage en captivité de MSN a été mis en place et son efficacité analysée, tandis qu’en parallèle deux séries d’expériences de traitement des déchets ont été réalisées. Ces différentes activités ont permis de démontrer que le co-traitement des DA et BA, ainsi que l’élevage en captivité de la MSN à l’aide d’un system low-tech est techniquement réalisable dans le contexte Ghanéen. Toutefois, des recherches supplémentaires sont nécessaires afin d’analyses les propriétés des produits de valorisation, d’établir le ratio DA/BV optimal, et d’optimiser les performances d’élevage. Enfin, une analyse coûts-bénéfices a été réalisée afin de comparer trois scenarios : (1) co-compostage des DA et BV afin de produire de l’engrais ; (2) co-traitement des DA et BV à l’aide de la MSN débouchant sur la production d’aliments pour animaux ; et (3) co-traitement des DA et BV à l’aide de la MSN pour produire à la fois des aliments pour animaux et de l’engrais. La construction de modèles financiers et la réalisation d’une analyse de sensibilité ont permis de démontrer que dans le contexte Ghanéen, le scenario (3) présentait la plus grande probabilité d’être viable et était le plus rentable, suivi par le scenario (1). En revanche, la probabilité que le scenario (2) soit viable s’est révélée beaucoup plus faible. Ultimement, la sélection de la meilleure méthode de valorisation devrait tenir compte du contexte et des priorités locaux.
536

Wind Power in Iowa and Ohio: Challenges and Opportunities

Ruiz, Joseph Patrick 26 October 2022 (has links)
No description available.
537

REIMAGINING BUILDING EFFICACY: AN EXPLORATORY STUDY

Domenique R Lumpkin (12639406) 17 June 2022 (has links)
<p>This dissertation focuses on the creation of a paradigm shift in building innovation. Challenges in achieving building energy-efficiency at scale highlight the complexity of the building performance problem, which is embedded with social, cultural, physical, environmental, and economic factors. Traditional approaches to building design have difficulty accounting for these multi-faceted variables and related longitudinal barriers and intangible impacts. Firstly, key stakeholders and their economic constraints change throughout time, and this variability is not traditionally considered upfront or addressed throughout a building’s operation. Secondly, buildings have social, cultural, environmental and economic implications that are difficult to quantify and evaluate against strictly functional design objectives. Therefore, current deeply technical and often system-specific building design strategies could benefit from whole-building solutions that account for this complexity and enable a paradigm shift in design toward human-centered outcomes (i.e., well-being, health, financial sustainability) and effective (i.e., equitable and sustainable) buildings. </p> <p>To drive this shift, an impact-based innovation framework was employed to pursue system-level and ecosystem-level strategies to optimize longitudinal building value assessment and distribution. First, a grounded theory study was pursued which identified gaps in current design practice that miss underlying building subsystem interactions which influence building performance. A system-level taxonomy of the building was then defined, linking identified sub-system synergies to functional, emotional and social building benefits for inhabitants. Then, an exploratory mixed-methods study was pursued, yielding a longitudinal building value framework that helps characterize key stakeholders, building design choices, and shared efficacy metrics. Building on these inputs, a multi-stakeholder, longitudinal building value assessment model was developed. The model was tested on two residential building development scenarios, highlighting its ability to capture the true impact of buildings on affected stakeholders over time in terms of tangible and intangible building costs and benefits. Finally, business model innovation concepts were employed to identify specific changes in stakeholder value delivery and capture strategies that could redistribute building costs and benefits over time, and thereby facilitate a shift in the paradigm of design and value capture in the residential building industry. </p>
538

Cost Modelling and Decision Making Model Generation for Urban Rail Transport Systems : MSc. thesis in collaboration with Trafikförvaltningen

Gökmen Dursun, Zekeriya January 2024 (has links)
Urban rail transport systems play a vital role in providing efficient and sustainable mobility solutions for growing metropolitan areas. This thesis focuses on the case of Stockholm's urban rail transport, managed by Region Stockholm, which serves nearly 900,000 daily passengers amid rapid population growth. However, the aging power supply system poses challenges to the system's efficiency and capacity expansion. To address these issues, this study develops cost modeling and decision-making tools aimed at evaluating future energy-saving business cases within the urban rail transport system. These tools, though preliminary, provide decision-makers with a techno-economic perspective to compare the cost-effectiveness of various measures and inform future interventions. The research methodology involves a system engineering approach, with continuous collaboration between the academic institution (KTH), transport authority (TF), and industrial partner (MTR). Weekly meetings facilitated the understanding of the urban rail transport system and the development of a decision-making algorithm. The study identifies stakeholders, primarily TF and passengers, and outlines a decision-making framework to assess proposed business cases. The tools generated undergo validation through expert feedback, laying the foundation for future empirical testing. Key findings highlight two main methods for energy-saving measures: technological modifications (e.g., Energy Storage Systems - ESS) and operational adjustments. Both On board and Wayside ESS installations demonstrate significant energy-saving potential, while operational adjustments such as HVAC modifications present challenges in automation. Qualitative reviews were made on these measures. The thesis proposes a preliminary Decision Making Tool to quantify Key Performance Indicators (KPIs) and facilitate informed decision making. Future work includes expanding stakeholder inclusion, refining cost models, and integrating additional business cases into the decision-making framework. In conclusion, this thesis contributes to the understanding of cost-effective measures for enhancing energy efficiency within urban rail transport systems. The developed tools offer an initial approach for decision-makers to navigate complex trade-offs and prioritize interventions, ultimately contributing to the sustainability and resilience of urban mobility infrastructure. / Järnvägstransportsystem i städerna spelar en viktig roll för att tillhandahålla effektiva och hållbara mobilitetslösningar för växande storstadsområden. Detta examensarbete fokuserar på fallet med Stockholms stadstrafik, som drivs av Region Stockholm, som servar nästan 900 000 dagliga passagerare i en snabb befolkningstillväxt. De åldrande strömförsörjningssystemen innebär dock utmaningar för systemets effektivitet och kapacitetsutbyggnad. För att ta itu med dessa frågor, utvecklar denna studiekostnadsmodellering och beslutsfattande verktyg som syftar till att utvärdera framtida energibesparande affärscases inom det urbana järnvägstransportsystemet. Dessa verktyg, även om de är preliminära, ger beslutsfattare ett tekniskt-ekonomiskt perspektiv för att jämföra kostnadseffektiviteten för olika åtgärder och informera framtida insatser. Forskningsmetodiken innebär ett systemtekniskt tillvägagångssätt, med kontinuerligt samarbete mellan den akademiska institutionen (KTH), transportmyndigheten (TF) och industriell partner (MTR). Veckomöten underlättade förståelsen av det urbana järnvägstransportsystemet och utvecklingen av en beslutsalgoritm. Studien identifierar intressenter, främst TF och passagerare, och skisserar en ram för beslutsfattande för att bedöma föreslagna affärsfall. Verktygen som genereras genomgår validering genom expertfeedback, vilket lägger grunden för framtida empiriska tester. Nyckelresultat belyser två huvudmetoder för energibesparande åtgärder: tekniska modifieringar (t.ex. Energy Storage Systems - ESS) och driftsanpassningar. Både ESS-installationer ombord och längs vägen uppvisar betydande energibesparingspotential, medan operativa justeringar som HVAC-modifieringar innebär utmaningar inom automatisering. Kvalitativa granskningar gjordes av dessa åtgärder. Avhandlingen föreslår ett preliminärt beslutsfattande verktyg för att kvantifiera Key Performance Indicators (KPI:er) och underlätta välgrundat beslutsfattande. Framtida arbete inkluderar att utöka inkluderingen av intressenter, förfina kostnadsmodeller och integrera ytterligare affärscase i beslutsfattandet. Sammanfattningsvis bidrar detta examensarbete till förståelsen av kostnadseffektiva åtgärder för att förbättra energieffektiviteten inom stadstrafiksystem. De utvecklade verktygen erbjuder ett första tillvägagångssätt för beslutsfattare att navigera i komplexa avvägningar och prioritera insatser, vilket i slutändan bidrar till hållbarheten och motståndskraften hos mobilitetsinfrastrukturen i städerna.
539

A Web-Based Respondent Driven Sampling Pilot Targeting Young People at Risk for Chlamydia Trachomatis in Social and Sexual Networks with Testing: A Use Evaluation

Theunissen, K., Hoebe, C., Kok, G., Crutzen, R., Kara-Zaitri, Chakib, de Vries, N., van Bergen, J., Hamilton, R., van der Sande, M., Dukers-Muijrers, N. January 2015 (has links)
Yes / With the aim of targeting high-risk hidden heterosexual young people for Chlamydia trachomatis (CT) testing, an innovative web-based screening strategy using Respondent Driven Sampling (RDS) and home-based CT testing, was developed, piloted and evaluated. Two STI clinic nurses encouraged 37 CT positive heterosexual young people (aged 16-25 years), called index clients, to recruit peers from their social and sexual networks using the web-based screening strategy. Eligible peers (young, living in the study area) could request a home-based CT test and recruit other peers. Twelve (40%) index clients recruited 35 peers. Two of these peers recruited other peers (n = 7). In total, 35 recruited peers were eligible for participation; ten of them (29%) requested a test and eight tested. Seven tested for the first time and one (13%) was positive. Most peers were female friends (80%). Nurses were positive about using the strategy. The screening strategy is feasible for targeting the hidden social network. However, uptake among men and recruitment of sex-partners is low and RDS stopped early. Future studies are needed to explore the sustainability, cost-effectiveness, and impact of strategies that target people at risk who are not effectively reached by regular health care.
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台電需求面管理之經濟分析--用戶計劃性減少用電措施案例 / The economic analysis of Taipower’s demand-side management--The case of incentive plan for load curtailment program

謝嘉豪 Unknown Date (has links)
過去電力事業為了滿足電力用戶之需求,對於新電源之開發不遺餘力。然而由於電力事業近年來在供給面規劃屢遭當地居民抗爭而受阻,因而晚近轉而強調用戶需求面之管理。 本文針對台電公司現行需求面管理之「用戶計劃性減少用電措施」四種方案進行研析。首先設定簡化條件,將四種方案予以模型化,利用經濟剩餘模型,進行邊際分析,探討台電公司提供優惠之折扣比例及電力的價格需求彈性如何參與用戶抑低容量以及消費者剩餘、生產者剩餘分配之效果。分析結果顯示:「計劃性(二)」抑低用戶負載容量最高,且參與用戶之消費者剩餘最多;「計劃性(一)」抑低用戶負載容量最低,且參與用戶之消費者剩餘最少。另一方面,若從電力公司之視角觀之,「計劃性(二)」之生產者剩餘最低,而「計劃性(一)」之生產者剩餘最高。 經濟剩餘模型分析中,由於未能充分考慮供需雙方之潛在成本與效益,因此實務上之解釋能力有其侷限之處。基於上述緣由,本文接著藉由成本效益分析,將方案實施之潛在成本與效益納入考量,分別從參與用戶之角度進行參與者檢定(Participant Cost Test, PCT)以及從電力公司之角度進行公用事業成本檢定(Utility Cost Test, UCT),以檢視不同方案在不同觀點下之績效表現。成本效益分析結果顯示:在PCT檢定下,「計劃性(四)」參與用戶之益本比最高,「計劃性(二)」參與用戶之益本比最低。而在UCT檢定下,「計劃性(一)」電力公司益本比最高,「計劃性(四)」電力公司益本比最低。將成本效益分析與經濟剩餘模型比較後可發現,用戶抑低容量高的方案對於電力公司而言未必最有利。 最後,為進一步探討關鍵變數變動造成不同方案間成本效益值之影響,因此進行敏感度分析。敏感度分析的結果顯示:若電力公司為吸引用戶而提高誘因,增加各方案給予用戶優惠折扣之比例,以參與用戶角度而言,「計劃性(四)」參與者檢定之益本比提高幅度最大;以電力公司角度而言,「計劃性(四)」公用事業成本檢定之益本比降低幅度最大。若電力公司提高參與用戶每次抑低用電負載之時數,以參與用戶角度而言,「計劃性(四)」參與者檢定之益本比降低幅度最大;以電力公司角度而言,「計劃性(四)」之公用事業成本檢定益本比提高幅度最大。 / In order to meet the users’ demand of electricity, the electric power utility spared no effort to develop the new power plant in the past. However, in recent years, the electric power utility have been hampered by local residents on supply-side planning, thus more emphasize is being put on users’ demand-side management(DSM). This paper aims to analyze four projects of Taipower’s existing demand-side management of “incentive plan for customers’ scheduled load curtailment program”. First, we set several simplified conditions for modeling the projects. By using the economic surplus model and conducting the marginal analysis, the impact from the discount incentive provided by the utility and the elasticity of electricity price demand is explored-on participants’ load capacity reduction and the distribution of consumer surplus and producer surplus. The results of economic surplus model showed "project 2" curtails the maximum load capacity and with the highest consumer surplus; "project 1" curtails the minimum load capacity and with the lowest consumer surplus. On the other hand, in the Taipower's point of view, "project 2" provides with the lowest producer surplus while "project 1" gives the highest producer surplus. In the economic surplus model, since the potential costs and benefit were not fully considered in both supply and demand sides, several limitations exist on this model. Based on the above reasons, we utilize the cost benefit analysis, taking the potential cost and benefit into account and conducting Participant Cost Test(PCT) from the participants’ perspective and Utility Cost Test(UCT)from the utility’s perspective to examine the performance under different 4 DSM projects in different point of view. The results of cost benefit analysis showed that in the PCT test, the "project 4" comes up with the highest benefit cost ratio while "project 2" has the lowest cost benefit ratio. In the UCT test, the "project 1" has the highest cost benefit ratio while "project 4" came with the lowest cost benefit ratio. Comparing the cost benefit analysis with the economic surplus model, we could find that the project with the most load capacity reduction may not be the most favorable project for the utility. Finally, in order to further explore the key variables affecting the cost and benefit value in different projects, we simulated several scenarios for sensitivity analysis. The results of the sensitivity analysis showed that if the utility increases incentives to increase four projects’ ratio of discount for attracting participant, in the participants’ perspective, "project 4" would have the most changed rate of cost benefit ratio(increase); in the utility's perspective, "project 4" would have the highest adjusted rate of cost benefit ratio(decrease). If the utility increases the load curtailment duration each time, in the participants’ perspective, "project4" would have the highest adjusted rate of cost benefit ratio(decrease) ; in the utility’s perspective, " project4 " would have the highest adjusted rate of cost benefit ratio(increase).

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