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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.
781

Teacher Tenure

White, W. D. 08 1900 (has links)
This study examines teacher tenure and the effect it has on education, children, and the public in order to determine whether or not legislation is needed.
782

Intressekonflikter vid användningen av besiktningsklausuler / Conflicts of Interest with the Use of Inspection Clauses

Rossander, Hugo, Kalle, Larsson January 2021 (has links)
Uppsatsen behandlar fastighetsköp med besiktningsklausuler medtagna i köpekontraktet och de intressekonflikter som kan komma att uppstå mellan köpare och säljare. Grundregeln visar på att köparens undersökningsplikt skall uppfyllas innan ett köp genomförs enligt 4:19 2 st JB. Undersökningen av fastigheteten görs efter att köpekontrakt upprättats vid användning av en besiktningsklausul. Köparen ges alltså med en besiktningsklausul rätten att utföra sin undersökningsplikt och besiktiga fastigheten efter genomförandet av köpet. Besiktningsklausuler medtagna i köpekontrakten är något som blir allt vanligare på den svenska fastighetsmarknaden till följd av att parterna vill komma till snabba avslut.    Det finns två typer av besiktningsklausuler att använda sig av, öppna och begränsade. En öppen besiktningsklausul liknas vid ett öppet köp inom den tidsfrist som står angiven i klausulen och leder sällan till tolkningsproblem även om det förekommer. Oavsett vad besiktningen påvisar kan köparen begära köpets återgång.  Vid en begränsad besiktningsklausul medtaget i köpekontraktet måste vissa villkor vara uppfyllda för att köpare skall kunna begära köpets återgång. Besiktningen måste då exempelvis påvisa specifika fel eller att fel och brister skall uppnå ett visst belopp, det vill säga en tröskel. Det är vid användning av den sistnämnda klausulen som det på senare år uppstått en rad tvister köpare och säljare emellan. Tolkningar av innehållet har skilt sig åt mellan parterna, eftersom formuleringarna inte är helt tydliga och klarlagda. Besiktningsklausulernas utformning finns inte reglerade i svensk rätt varför formuleringarna kan skilja sig åt i varje enskilt fastighetsköp vilket resulterar i olika rättsverkningar.
783

How to Create Monsters? A preliminary examination approach to the role of the social environment in relation to the origin of South African serial killers

Wehner, Jana 22 March 2022 (has links)
The phenomenon of serial killers is a fascinating topic for readers, as well as for researchers. This dissertation is going to expand the steadily growing stock of literature regarding the origin of serial killers, but with a focus on the social environment. As the social environment differs from country to country, depending on cultures, history, societies, and economic circumstances, it is important to take a South African perspective when studying the social environment of individuals in South Africa. After explaining the different approaches to define the term `serial killer´, this paper provides a solid review of previous research on the origin of serial homicide in South Africa. While presenting the most popular theories on the origin and development of serial killers in South Africa, it becomes evident that the social environment has never been considered to be a factor that might play a role. This paper criticises the fact that an examination of the social environment of serial killers has been absent in previous research on the development of serial killers. Consequently, it makes it its task to examine the social environment of South African serial killers via multiple case studies. Six South African serial killer cases are presented and the social environment of the individuals is explained. Moreover, similarities between the cases and other conspicuities are pieced together and analysed, followed by a discussion on how they might have an impact on a serial killer. Additionally, the paper gives some food for thought on why the social environment in South African townships is so fertile for serial killers to offend and what cultural and historical circumstances might play a role in developing such an environment. Providing incentives for further in-depth research here and there, this research expands the steadily growing body of literature on serial killers from a South African perspective. The paper concludes that the social environment of serial killers is a huge and interesting subject area, with many possible influencing factors that are therefore worth exploring further. Additionally, this paper proposes that the social environment should be taken into account when researching serial killers in general, and especially their origin and development. This paper takes the initiative to research the social environment as an independent factor within the phenomenon of serial killers. It proposes a preliminary examination approach to the role of the social environment in relation to the origin of South African serial killers for the purpose of drawing attention to the importance of including it when researching serial killers to generate a better understanding of the origin of serial killers and the phenomenon in general.
784

Variability in the emissions savings potential of battery electric vehicles across regions and individuals

Miotti, Marco,Ph. D.Massachusetts Institute of Technology. January 2020 (has links)
Thesis: Ph. D. in Engineering Systems, Massachusetts Institute of Technology, School of Engineering, Institute for Data, Systems, and Society, February, 2020 / Cataloged from student-submitted PDF version of thesis. / Includes bibliographical references (pages 219-232). / Personal vehicles account for almost 25% of U.S. greenhouse gas emissions, and this share is increasing. The increase is due to several factors, including a growth in transportation demand and the decarbonization of electricity by 30% since 2007. Alternative technologies for road vehicles, such as battery electric, plug-in hybrid, and fuel cell powertrains have the potential to achieve significant emission reductions. Yet questions remain about the emissions and costs of these alternative technologies. This thesis evaluates the emissions reduction potential of vehicles with electrified powertrains, focusing on battery electric vehicles (BEVs). It evaluates this potential taking into account heterogeneous regional conditions and consumer behavior. Consumers help determine vehicle fleet emissions through their purchasing and driving decisions, which are guided in part by the costs of different options. / Therefore, the costs of ownership of BEVs in comparison to conventional vehicles inform the emissions reduction potential of BEVs. Here, we measure the lifecycle greenhouse gas emissions and costs of ownership of BEVs across different vehicle models as a function of travel patterns, driving styles, and properties of the natural, built, and institutional environment. We compare these costs and emissions to gasoline combustion engine vehicles (ICEVs), and then ask whether and under which condition electric vehicle adoption can play a central role in meeting emission targets for the transportation sector. The current literature does not cover all the interdependent sources of variation in the emissions and costs of BEVs compared to ICEVs. In particular, the effects of annual travel distance and fuel efficiency related to individual travel behavior and the wide variety of available vehicle models have not been assessed. / In addition, this variation in emissions and costs of personal vehicles has only been studied across regions, but not across individual vehicles within each region due to vehicle-specific driving patterns. This work addresses these gaps by developing several interlinked models. This includes the construction of a parametrized lifecycle emissions and cost of ownership model (Chapter 2), an algorithm to measure driving style linked to a vehicle energy model (Chapter 3), and a model to quantify the variability in annual travel distance and fuel consumption of different types of vehicles across regions within the United States, encoded as zipcodes, and across individual vehicles within those zipcodes (Chapter 4). Chapter 5 then ties Chapters 2 and 4 together and complements them with additional information to assess the overall heterogeneity in the emissions reduction potential of BEVs. The central results of the thesis are threefold. / First, a rapid decarbonization of electricity in conjunction with an electrification of powertrains will likely be required to meet emission targets for the U.S. transportation sector. Measures that relate to heterogeneous consumer behavior, such as improving driving style and nudging consumers towards purchasing smaller vehicles, can help to reduce greenhouse gas emissions. Second, the electrification of powertrains can come at little to no additional expense to consumers with today's technology and prices. In most parts of the country, BEVs are substantially cheaper than comparable ICEVs. Within regions, the individuals for which BEVs offer the greatest emissions savings would also tend to experience the largest cost savings, since both emissions savings and cost savings are correlated with annual travel distance. Third, emission reductions achieved by BEVs and their costs relative to ICEVs are highly heterogeneous. / The within-region variation in emissions and costs of BEVs compared to ICEVs due to individual driving patterns is at least as large as the variation across regional averages. As a result, a 10% share of BEVs in the fleet can lead to anywhere between 1% and 10% emission reductions, depending on which types of vehicles are being replaced by electric vehicles, by whom, and where. A key application of this work is to inform tools that provide localized and personalized information about the environmental and economic performance of different vehicle models. In Chapter 6, we discuss such a tool that was built as part of this work, called Carboncounter.com. Results from a survey launched on Carboncounter add to existing evidence that providing such information to consumers can help inform a transition to a cleaner light-duty vehicle fleet. These findings further confirm the importance of understanding heterogeneous human behaviors to inform decarbonization strategies for personal transport. / by Marco Miotti. / Ph. D. in Engineering Systems / Ph.D.inEngineeringSystems Massachusetts Institute of Technology, School of Engineering, Institute for Data, Systems, and Society
785

Market design opportunities for an evolving power system

Schneider, Ian Michael. January 2020 (has links)
Thesis: Ph. D. in Social and Engineering Systems, Massachusetts Institute of Technology, School of Engineering, Institute for Data, Systems, and Society, February, 2020 / Cataloged from student-submitted PDF version of thesis. / Includes bibliographical references (pages 117-126). / The rapid growth of renewable energy is transforming the electric power sector. Wind and solar energy are non-dispatchable: their energy output is uncertain and variable from hour-to- hour. New challenges arise in electricity markets with a large share of uncertain and variable renewable energy. We investigate some of these challenges and identify economic opportunities and policy changes to mitigate them. We study electricity markets by focusing on the preferences and strategic behavior of three different groups: producers, consumers, and load-serving entities. First, we develop a game-theoretic model to investigate energy producer strategy in electricity markets with high levels of uncertain renewable energy. We show that increased geographic dispersion of renewable generators can reduce market power and increase social welfare. We also demonstrate that high-quality public forecasting of energy production can increase welfare. Second, we model and explain the effects of retail electricity competition on producer market power and forward contracting. We show that increased retail competition could decrease forward contracting and increase electricity prices; this is a downside to the general trend of increased access to retail electricity competition. Finally, we propose new methods for improving demand response programs. A demand response program operator commonly sets customer baseline thresholds to determine compensation for individual customers. The optimal way to do this remains an open question. We create a new model that casts the demand response program as a sequential decision problem; this formulation highlights the importance of learning about individual customers over time. We develop associated algorithms using tools from online learning, and we show that they outperform the current state of practice. / by Ian Michael Schneider. / Ph. D. in Social and Engineering Systems / Ph.D.inSocialandEngineeringSystems Massachusetts Institute of Technology, School of Engineering, Institute for Data, Systems, and Society
786

Effects of hardware and soft features on the performance evolution of low-carbon technologies

Klemun, Magdalena Maria. January 2020 (has links)
Thesis: Ph. D. in Engineering Systems, Massachusetts Institute of Technology, School of Engineering, Institute for Data, Systems, and Society, February, 2020 / Cataloged from student-submitted PDF version of thesis. / Includes bibliographical references (pages 295-328). / This dissertation studies how physical and non-physical features of low-carbon technologies evolve and influence performance evolution. This fundamental question about the role of hardware- and non-hardware ('soft') innovations in technological progress remains largely unanswered despite the societal importance of improved technology. Multiple low-carbon technologies exhibit rising shares of soft costs, and understanding their determinants is thus critical to support climate mitigation. However, building this understanding is challenging. Technologies evolve through multi-faceted knowledge-generating processes, in which both endogenous factors, such as a technology's design, and exogenous factors, such as policies and research, play roles. / To capture this complexity, a new conceptual and quantitative model of technology performance evolution is developed, where performance change (e.g., cost change) is the outcome of changes in physical and non-physical ('soft') features ('variables'), both of which can affect the performance of hardware and processes needed to deploy technologies. While physical variables -- material usage ratios, efficiencies -- / describe the tangible aspects of technologies, soft variables (e.g., task durations, wages) characterize the performance of intangibles, including deployment processes and services. In contrast to physical variables, soft variables can change after the factory gate due to locational differences in technology management or labor costs. By defining hardware and soft performance as functions of both hardware and soft variables, and separating their contributions to cost change when multiple variables change, this framework disentangles the effects of physical and non-physical forms of improvement at multiple conceptual levels -- / from changes in hardware or soft features, to the specific physical and non-physical innovations that drive these changes, to the higher-order improvement processes in which many innovations originate (e.g., research and development). This approach addresses shortcomings in current methods to analyze and track cost change in technologies, which often treat the performance of hardware (e.g., equipment costs) and of deployment processes (e.g., soft costs) separately. However, features of hardware not only affect the cost of equipment, but also the cost of deploying this equipment, and accounting for such interdependencies can change assessments of the sources of past and future technology improvement ... / by Magdalena Maria Klemun. / Ph. D. in Engineering Systems / Ph.D.inEngineeringSystems Massachusetts Institute of Technology, School of Engineering, Institute for Data, Systems, and Society
787

Individual and organizational Uses of Evidence-Based Practice in healthcare settings / Individual and organizational Uses of EBP in healthcare settings

Fingerhut, Henry Alan. January 2020 (has links)
Thesis: Ph. D. in Engineering Systems: Technology, Management, and Policy, Massachusetts Institute of Technology, School of Engineering, Institute for Data, Systems, and Society, February, 2020 / Cataloged from student-submitted PDF version of thesis. / Includes bibliographical references (pages 135-145). / In the three decades since its introduction, Evidence-Based Practice (EBP) has become standard clinical practice and the subject of targeted interventions at all levels of the health system. Despite its prevalence, EBP is frequently challenged on philosophical, practical, empirical, and normative grounds. And EBP is often underused in practice relative to the considerable investment in training and sophisticated organizational interventions to implement EBP. In this dissertation, I identify what the concept of EBP means to health system stakeholders as a partial explanation for this persistent gap in EBP use and implementation outcomes. Through interviews with clinicians and healthcare administrators, I identify how providers and organizations use EBP in practice to clinical ends and in inter-professional relationships. First, I find that in contrast to the theoretical model, stakeholders vary in how they operationalize EBP for individual-level clinical use. / Stakeholders endorse a range of what I call implicit mental models of EBP that imply different approaches to clinical decision-making. Respondents' implicit mental models of EBP each emphasize an incomplete aspect of the full EBP model: Resource-Based EBP emphasizes specific evidence artifacts, Decision-Making EBP emphasizes the decision-making process, and EBT-Based EBP emphasizes specific Evidence-Based Treatments. These implicit models represent the decision inputs, process, and outputs, respectively. Second, I describe how and why healthcare organizations conduct EBP interventions, despite its initial design as an individual-level clinical decision-making model. I document a range of different organizational EBP activities and interventions, including disseminating resources, training providers, and implementing local standards. These organizational EBP activities both support individual EBP use and address broader organizational ends, which may conflict. / Finally, EBP takes on social and inter-professional meanings beyond its intended scope as a clinical decision-making model, which emerge in context and affect how providers understand and use EBP. Specifically, providers may renounce their standing to evaluate evidence, demonstratively use EBP, and administrators claim standing to evaluate evidence. This dissertation therefore demonstrates the varied uses of EBP that emerge in practice, contributing to our understanding of the challenges and contradictions that arise in applying general knowledge to individual cases and systematizing strategies for the same at the organization level. / by Henry Alan Fingerhut. / Ph. D. in Engineering Systems: Technology, Management, and Policy / Ph.D.inEngineeringSystems:Technology,Management,andPolicy Massachusetts Institute of Technology, School of Engineering, Institute for Data, Systems, and Society
788

Firms, industries, and technological change : a patent-based approach to studying disruption and disruptors / Patent-based approach to studying disruption and disruptors

Metzler, Florian. January 2019 (has links)
Thesis: Ph. D. in Engineering Systems, Massachusetts Institute of Technology, School of Engineering, Institute for Data, Systems, and Society, 2019 / Cataloged from PDF version of thesis. / Includes bibliographical references. / This thesis presents a new empirical approach as well as a new patent-based dataset for studying disruption and technology transition cases. At the core of this approach lies a novel engineering systems framework of technological change. The framework focuses on the relationship between changes in technological competencies and changes in product designs, and encompasses both firm-level and industry-level dynamics. The new framework and dataset are applied to the study of three cases of technology transition during the 1993- 2012 period. The cases include (1) disruption in the mobile phone industry with a focus on Apple, BlackBerry, and Nokia; (2) disruption in the photography industry with a focus on Fujifilm, Canon, and Kodak; and (3) technology transition in the automotive industry with a focus on Toyota, Volkswagen, and GM. / The former two industries comprise widely discussed disruption cases, allowing me to demonstrate advantages of the presented approach and develop novel insights into these cases. The third case, on the automotive industry, generates complementary insights by considering an industry with products comprising more integrated product architectures. The case selection allows for cross-case comparisons to begin endogenizing industry-specific factors. The thesis' main contributions are methodological and theoretical: First, I present a new dataset - and corresponding data assembly methods - of comprehensive corporate patent portfolios. The portfolios take into account each firm's corporate family tree structure as well as acquisitions. As such, the dataset reflects the actual range of firms' codified technological activities more closely than previous efforts and enables a more accurate view on how technological change manifests in firms and industries. / To connect the data to theory, I develop a set of novel metrics to operationalize semantic concepts such as technological diversification and concentration of portfolios as well as firms' technological core and growth competencies. These metrics are based on a newly developed variance measure for hierarchically structured networks. I define growth competencies as competencies that undergo rapid year-to-year growth outside of a firm's core competencies. By identifying incumbents' growth competencies from historical data before major transitions, I am able to successfully hindcast future new entrants in the cases presented. Further, I introduce the concepts of technology space and product space as mappings of compositions of technological competencies and of technological competencies required by compositions of products. Second, the thesis makes theoretical contributions to resource-based view (RBV) and disruption literatures. / Specifically, it presents a dynamic extension to the RBV, endogenizing technological change as well as firm-industry interconnections with regard to the emergence of technology convergences and the evolution of product designs. My findings suggest that a firm's relative position and movement in technology space needs to be considered separately from its position and movement in product space, i.e. its changing composition of competencies and its changing composition of products. Specifically, whereas firms' movements in product space can appear abrupt and even surprising - such as the sudden entry into new markets - my analysis shows that changes in technology space tend to be slower, more continuous, and more predictable. / I find that in disruption cases such as with Apple's sudden "entry" into the mobile phone industry, the new framework reveals that it was in fact the mobile phone industry that gradually "entered" Apple's position in technology space - as the technological requirements of phone industry products became more and more similar to Apple's preexisting, and highly stable, competencies. Moreover, I extend the concept of technology-product connections, as put forth statically by RBV theorists, by adding a time-dependent dimension. I argue that incumbent failure - such as Nokia's and Kodak's - can be explained by incumbents' inability to diagnose and respond to the gradual weakening of their technology-product connections; in other words, by neglecting to either adjust their technological competencies or to adjust their product offerings in response to technological change. / In turn, a firm with greater awareness of its own composition of technological competencies relative to its competitors as well as the changing technological requirements of prevalent product designs can deliberately incorporate such insights into strategic decision-making. In the empirical cases, I observe the ability to sense dynamics in technology and product spaces relative to the firm, and the ability to time the firm's actions accordingly, to be more present in some firms than in others. I term the existence of such abilities timing and sensing capabilities and propose them to be a concrete and operationalizable subset of Dynamic Capabilities. / by Florian Metzler. / Ph. D. in Engineering Systems / Ph.D.inEngineeringSystems Massachusetts Institute of Technology, School of Engineering, Institute for Data, Systems, and Society
789

The civil society of Colombia

Evans, Van C. 16 May 2016 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / The Republic of Colombia, with approximately 48 million inhabitants, is the fourth largest country by population in the Americas, after the U.S., Brasil, and México. It is divided politically into 32 departments and 10 districts with 1101 municipalities. Colombia has a rich history of philanthropy and solidarity since colonial times. Together, with the political strife of the past, these shed light on present day philanthropic practices and trends toward thriving civil society formation in the country. In order to strategically address human challenges and strengthen civil society in Colombia, a vision of what the civil society landscape looked like was needed. No such system existed in Colombia, and the extent and breadth of the sector was not known. The federal government has no single database that tracks the sector. Therefore, the primary research question for this case study is—What is the size and scope of civil society in Colombia? This dissertation, in good measure, provides the answer. It provides a geographical and taxonomical map of civil society organizations (CSOs) in Colombia. This dissertation also examines how Colombia came to have a thriving civil society sector yet lack a federal registry. Findings show there are 24 federal and capital district registries of different types of civil society. Moreover, each of the 32 departments have registries for health and education and some also register CSOs related to environment, culture, sports, and recreation. Findings from 21 of the 24 federal or district registries and three of the 32 departments reveal a total of 296,467 CSOs. This constitutes an estimate of 98.60 percent of all possible records. There is approximately one CSO for every 163 inhabitants or 61.5 CSOs for every 10,000 inhabitants, giving Colombia the highest number of registered CSOs per capita in the Americas, save the United States. The National Taxonomy of Exempt Entity (NTEE) codes were applied to CSOs, where possible. Findings reveal Colombia has a balanced civil society, with no subsector greater than 33 percent of total CSOs.
790

Climatological variables associated with increased mortality rates for diseases predominant during the cold season

Sedorovich, Ashley Johanna 01 May 2010 (has links)
Previous research indicates a distinct seasonal pattern in mortality rates. Increases are prominent during the northern-hemispheric cold season. These patterns are seen in overall mortality, diabetes mellitus, circulatory, digestive, and respiratory diseases. A principal component analysis indicates that departure from normal temperature, minimum, maximum, and average daily temperature, and dew-point temperature are the primary atmospheric variables that influence mortality patterns. ANOVA and Kruskal-Wallis tests support findings of principal component analysis. Although a day-to-day relationship between mortality rates and atmospheric variables was noted in several instances, results suggest that the influence of the primary atmospheric variables on mortality rates is greatest when a three to five-day lag time is in place. Furthermore, results indicate that the combination of these variables in conjunction with frontal passage is linked to seasonal increases in mortality. A combination of atmospheric variables that influence mortality rates has been identified, however, their exact influence is still unclear.

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