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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.
111

Spatial and temporal aspects of high-latitude particle precipitation: a remote diagnostic of magnetospheric regions and processes

Boudouridis, Athanasios January 2001 (has links)
Thesis (Ph.D.)--Boston University / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / Due to the direct magnetic connection of the high-latitude ionosphere to the outer magnetosphere, a great deal of knowledge of the physics and properties of magnetospheric regions and the fundamental plasma processes operating within them can be learned from studying low-altitude particle measurements. In this thesis the temporal and spatial aspects of the low-altitude auroral particle precipitation are investigated using a unique set of particle flux observations from two Defense Meteorological Satellite Program (DMSP) spacecraft in the same orbit but with varying time separation. Three different topics are investigated in this study: auroral stability, the accuracy of the Newell-Meng criteria for region identification, and the relative importance of various magnetopause reconnection models. In the first part the prevalent timescales and spatial dimensions of low-altitude auroral formations are examined using both electron and ion data. It is found that spatial scales larger than 50-100 km are stable for up to 1.5 minutes, while smaller size features vary more rapidly. In the second topic we explore quantitative and qualitative aspects of the Newell-Meng criteria. The flexibility and limitations of the numerical values used are examined with case and statistical studies; all but one are found to be sufficiently robust. Additionally, an expansion of the criteria to include a distinction between open and closed magnetic field line geometries is considered. The last part concentrates on the evaluation of currently proposed models of magnetopause reconnection, based on a case study of ion and electron low-altitude particle reconnection signatures. We conclude that a unique combination of the multiple x-line and bursty single x-line reconnection models is required for a full interpretation of the data. This scenario also provides a comprehensive mechanism for the formation of the low-latitude boundary layer on both open and closed field lines. Finally, the common conclusion of all three studies is that two-point measurements add considerably to our understanding of the low-altitude auroral environment and thereby, the remote processes governing its dynamics. / 2031-01-01
112

Spojování podniků a soutěžitelů a ekonomická kritéria / Analysis of merger regulation and economical criteria

Gonda, Pavel January 2013 (has links)
Analysis of merger regulation and economical criteria Abstract: The United States of America has been the cradle of merger regulation. During the last century, the application of rules connected with merger assessment was evolving in connection with the then-prevalent economic schools (for example the University of Chicago, etc.) and in connection with the amount of regulation of American economy during certain periods. The Courts make decisions whether or not a merger leads or does not to a significant lessening of competition, whereas the petitioners can be persons affected by relevant merger, states or federal antitrust Agencies (FTC or DOJ). The notifications of the merging parties are being filed with the above Federal Antitrust Agencies according to the Hart-Scott-Rodino Antitrust Improvements Act. There are two possible anticompetitive effects of mergers - unilateral effects and coordinated effects. Both effects complement each other. These effects can be prevented by efficiency gains of the merged entity. The merger assessment in the European Union or the Czech Republic is relatively new in comparison with the US. In contrast to the US, the concentrations in the EU and the Czech Republic are cleared by the Antitrust Agencies (namely the European Commission or Czech Competition Office). The decisions...
113

Revisão e análise ambiental e operacional de métodos de ecodesign baseados em QFD e FMEA / Environmental and operational review and analysis of ecodesign methods based on QFD and FMEA

Puglieri, Fábio Neves 15 September 2010 (has links)
A partir da década de 1990, iniciou-se uma difusão de métodos e ferramentas direcionadas à adequação ambiental de produtos, cuja aplicação é realizada em determinadas fases do seu desenvolvimento. Porém muitos destes métodos publicados não integram questões ambientais importantes, como a perspectiva de ciclo de vida, resultando muitas vezes no desenvolvimento de produtos ineficientes do ponto de vista do ecodesign. Assim, este trabalho tem por objetivo analisar alguns destes métodos de modo que possam garantir o desenvolvimento de produtos ambientalmente mais adequados. Para isto foi realizada uma revisão sistemática sobre requisitos para métodos de ecodesign, o que permitiu identificar características que o ecodesign deve atender, tanto do ponto de vista ambiental quanto do operacional. Por meio destes requisitos foram propostos critérios utilizados na análise de 19 métodos de ecodesign baseados no FMEA e no QFD. Como resultado da análise, identificou-se que a grande maioria dos métodos analisados não estão de acordo com o que a literatura sugere. / During 1990s decade began a scattering of methods and tools aimed at the environmental suitability of products whose application is performed at certain stages of development. However, many of these published methods do not incorporate important environmental issues, the prospect of life cycle, often resulting in inefficient product development from the standpoint of ecodesign. This study aims to examine some of these methods to ensure the development of more environmentally suitable products. So it was carried out a systematic review of ecodesign requirements for methods, which allowed us to identify characteristics that these methods must meet from the environmental point of view and application. Through these requirements have been proposed criteria used in the analysis of 19 ecodesign methods based on FMEA and QFD. As a result of this analysis, it was identified that most part of the methods reviewed are not in agreement with literature suggestions.
114

Perceptions of the Principal Evaluation Process and Performance Criteria: A Qualitative Study of the Challenge of Principal Evaluation

Casavant, Christopher, Collins, William, Faginski-Stark, Erica Ann, McCandless, Jason, Tencza, Marilyn January 2012 (has links)
Thesis advisor: Robert J. Starratt / Recent federal and state mandates have tasked school systems to move beyond principal evaluation as a bureaucratic function and to re-imagine it as a critical component to improve principal performance and compel school renewal. This qualitative study investigated the district leaders' and principals' perceptions of the performance evaluation process and criteria by which the effectiveness of principals was judged in a small, urban, New England school district. In an effort to assist the New England School District to create a more authentic principal evaluation process, district document analysis, literature review, interview transcripts and survey data were used to make recommendations to district leaders regarding four major themes including fairness, feedback, process and critical aspects. The themes were discussed in the context of schools as complex systems, where trust and distributive leadership drive school renewal. Emerging from the study of principal and superintendent perceptions of the process and criteria for evaluation, recommendations include: make principal evaluation an ongoing process; schedule time in each building; clearly identify criteria and supportive evidence; standardize rubrics and evaluation instrument; use evaluation instrument and feedback mechanisms that recognizes complexity of the principalship; provide meaningful feedback; and base summative evaluation on goals for personal-professional improvement and growth. / Thesis (EdD) — Boston College, 2012. / Submitted to: Boston College. Lynch School of Education. / Discipline: Educational Administration and Higher Education.
115

Análise e avaliação dos novos critérios de adjudicação de portos e terminais sob o novo marco regulatório do setor portuário brasileiro. / Analysis and evaluation of new bidding criteria for seaport and seaport terminal concessions under the new Brazilian regulatory regime.

Barros, Tiago Maciel de 08 October 2014 (has links)
Este trabalho compreende a análise e avaliação dos critérios de adjudicação de portos e terminais introduzidos pelo novo marco regulatório do setor portuário brasileiro. O objetivo principal consiste em avaliar se a aplicação na prática desses critérios deverá levar ao alcance dos objetivos da alteração do marco regulatório, a partir da MP 595/2012, depois convertida na Lei 12.815/2013: o aumento da oferta de capacidade e a redução dos custos portuários. A metodologia empregada consiste principalmente na revisão bibliográfica e na análise documental dos instrumentos legais e infralegais que regem o tema, bem como das minutas de editais e contratos dos primeiros arrendamentos de instalações que se prevê licitar sob os novos critérios de adjudicação. Dada a previsão de adoção de regulação econômica em parte significativa dos novos arrendamentos, discutem-se também aspectos da competição portuária e formas de regulação. Aborda-se ainda, resumidamente, outros aspectos que foram alterados a partir da MP 595/2012, especialmente a flexibilização dos requisitos para a outorga de autorização a terminais de uso privado e a centralização dos processos de arrendamentos nos órgãos setoriais (SEP e ANTAQ), em detrimento das autoridades portuárias. Conclui-se que os critérios de seleção a serem utilizados na prática em novos arrendamentos, a maior capacidade efetiva de movimentação e a menor tarifa, embora alinhados com os objetivos iniciais do novo marco regulatório, apresentam riscos à efetiva consecução desses objetivos. Enxerga-se um risco maior no caso das licitações com base na menor tarifa, em que a ausência de pisos para as tarifas nos leilões torna operadores verticalizados os vencedores naturais do processo nesse caso, a menor tarifa ofertada não deverá, na prática, resultar em menores custos aos usuários, já que a redução do valor no leilão pode ser repassada a outro elo da cadeia. / This study comprises the analysis of the criteria to be used in the concession of seaports and seaport terminals under the new Brazilian ports law. The studys main objective is to analyze if the application of these criteria will lead to the objectives that governed the change in the ports law, introduced by the Provisional Measure 595/2012, after converted in Law 12.815/2013: the increase of port capacity and the reduction of port costs. The methodology applied was mainly the research of the bibliography of the subject and the documental analysis of legal and infralegal instruments that govern the issue in Brazil, as well as the drafts of the bid documents of the first seaport terminals to be conceded under the new criteria. Aspects of port competition and regulation are also discussed, given the forecasted adoption of tariff regulation in a relevant part of the new port terminals concessions. The study also approaches other aspects that the Provisional Measure 595/2012 has changed, especially the reduction of the requirements for private terminals to be authorized and the centralization of seaport terminals concession procedures, which were former responsibilities from the Port Authorities, in federal bodies (SEP and ANTAQ). The conclusion of the study is that, despite being aligned with government initial objectives, the criteria to be applied highest throughput commitment or lowest tariff offer risks to the effective achievement of these objectives. The risk is higher in the bids based on the lower tariff, in which the absence of floors for the tariffs make vertically integrated players the natural winners of the bidding process in this case, the lower tariff offered will probably not result in lower costs for port users, once the reduction in the port tariff can be passed on to other links of the chain.
116

Solutions to multiple criteria and multiple dimensional problems in marketing. / 解決多重標準和多重空間的市場問題 / CUHK electronic theses & dissertations collection / Digital dissertation consortium / ProQuest dissertations and theses / Jie jue duo zhong biao zhun he duo zhong kong jian de shi chang wen ti

January 2000 (has links)
The second marketing model addresses interpretation issues of traditional multiple dimensional scaling (MDS) model, and has three key features. First, it can provide an explicit meaning to each dimension. Second, it can directly provide a link between brand positions and brand attributes, so that marketing mix can be designed to optimize share or profit. Third, for a case of n brands and m product attributes, we only need to estimate m nonzero parameters to represent all brand positions in the reduced space of d dimensions where d < m. The model is applied to a real data set of thirty four cars and nine attributes. Empirical findings suggest that the proposed model is a viable alternative to existing methods. / This thesis proposes two marketing models. The first model is a multiple criteria ranking (MCR) model. It proposes a consensus approach to solve multiple criteria ranking problems. Marketing decisions frequently involve ranking various subjects using multiple criteria. However, it is difficult to have acceptance from all subjects. The proposed multiple criteria ranking model allows each subject to have a "say" in the evaluation process. All subjects together resolve their conflicts through voting so that consensus ranking can be derived under the majority rule principle. The new ranking procedure can be formulated as a series of mathematical programming models, and illustrated with two cases. First, ranking the research performance of thirty one marketing scholars according to their publications in four leading marketing journals. Second, ranking the performance of one hundred information technology companies. / Lam Pong Yuen. / "June 2000." / Added t.p. in Chinese. / Director: Lau Kin Nam. / Source: Dissertation Abstracts International, Volume: 61-08, Section: A, page: 3259. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2000. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest dissertations and theses, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
117

Vícekriteriální optimalizace v projektovém řízení / Multi-criteria Optimization in Project Management

Křenková, Michaela January 2011 (has links)
Multi-criteria decision making is a common issue in everyday life. If the decision doesn't have a significant impact on the future of the company, it is possible to decide intuitively. However, if they do have such an impact, it is sensible to use decision methods. A company implementing changes via projects might find itself in a situation, where it doesn't have enough resources to execute all projects at once and therefore the company has to decide which projects shall be executed, when and in which order. The choice of an appropriate method also depends on other factors. If the company has strictly defined restrictions it is possible to use multi-criteria programming methods; if the company wants to know the order in which to execute the projects, it will use one of the methods of multicriteria evaluation of options. If there are multiple decision-makers, whose decisions might vary, it is possible to use team expert choice methods. The next important task after choosing the project selection method is to prepare project plans, also based on appropriate methodology.
118

Hodnocení ředitelů základních škol a mateřských škol z pohledu obecních zřizovatelů v Plzeňském kraji a stanovení kritérií hodnocení / Evaluation of directors of elementary schools and kindergartens from the perspective of municipal founders in the Pilsen region and determination of evaluation criteria

Chottová, Miroslava January 2012 (has links)
5 TITLE: Evaluation of directors of elementary schools and kindergartens from the perspective of municipal founders in the Pilsen region and determination of evaluation criteria. AUTHOR: Miroslava Chottová DEPARTMENT: Centre for Education Management SUPERVISOR: Doc. Jaroslav Kalous, Ph.D. ABSTRACT: The main subject of this dissertation is process of evaluation of directors at elementary schools and kindergartens by municipal founders in region of Pilsen and matters related to it. The content is based on specialized literature, results of questionnaire research done with the municipal founders and also the directors of elementary schools and kindergartens, and practical experience. The partial objective of this work is to confirm or alternatively disprove hypotheses regarding the evaluation of the directors at elementary schools and kindergartens by municipal founders (evaluation according to criteria, evaluation as a motivational factor), based on mapping the methods of assessment of the directors and the criteria currently applied by the founders. The main objective of this work is to process a sample for methodical evaluating procedure including a sample set of evaluating criteria, based on findings in the specialized literature and questionnaire research, and own experience. The methodical procedure...
119

Multi-criteria preference aggregation framework for sustainable energy planning

Santos-Ramos, Raquel January 2018 (has links)
In the energy field, the decisions need to take into consideration several factors such as the needs of the population, the environment, suitability, capital cost, sustainability, political goals and the actors involved, with their interests and preferences. The lack of homogeneity in all the factors that must be consider makes it necessary to design a process that guides the analysis process of any type of decision-maker. Decision analysis methods have been developed to aid decision-makers identify a problem, determine the criteria to be consider and their importance, recognize the stakeholders that need to be involved and pose the different alternatives to resolve or to best address the problem. These techniques range from simple to more mathematically oriented ones, from single criterion evaluation to multiple criteria, and from purely qualitative or quantitative to mixed techniques. Within the field of decision analysis, multi-criteria techniques are better suited to aid in decision situations in the energy field as these decisions require several considerations beside economic ones. This thesis uses theories and notions of decision analysis to construct a framework to be used in any energy related decision situations by non-experts. The framework tackles common challenges faced by multi-criteria decision analysis methods, including the identification of stakeholders and decision-makers, the aggregation of various decision-makers, preferences and heterogeneous inputs, and the selection of suitable criteria, alternatives and methods.
120

Testemunha de emaranhamento generalizada / Generalized entanglement witness

Lima, Rafael Bruno Barbosa 19 February 2015 (has links)
Desde o surgimento da mecânica quântica no início do século XX, ela vem sendo alvo de diversos estudos e suas característcas fazem com que a mesma seja descrita de forma totalmente diferente da teoria clássica. Com o aprofundamento em suas áreas, surgiram novos conceitos e a compreensão sobre a teoria da informação e computação quântica foi radicalmente mudada devido a uma propriedade básica da mecânica quântica, o emaranhamento. Assim, a popularização da ideia do computador quântico trouxe consigo uma série de pesquisas relacionadas a informação quântica e suas aplicações no mundo real. Nesta dissertação apresentamos um estudo sobre a construção de um critério de emaranhamento geral, no qual podemos aplicá-lo a quaisquer sistemas possuindo um Hamiltoniano descrito por cadeias de spins, seja ele bipartido ou multipartido. Esse critério é baseado na covariância de um observável geral que pode ou não possuir termos de interações entre os spins. Entretanto, esse critério pode ser facilmente reduzido a variância, uma vez que esta é muito mais adequada para a aplicação em sistemas físicos. Desta maneira, podemos utilizar a susceptibilidade magnética e o calor específico como testemunhas de emaranhamento para o critério, em razão da sua facilidade de medidas experimentais. / Since the advent of quantum mechanics in the early twentieth century, it has been the subject of several studies and their features cause it to be described quite differently from classical theory. With the deepening in their fields, there were new concepts and understanding about information theory and quantum computing has been radically changed due to a basic property of quantum mechanics, the entanglement. Thus, the popularization of the idea of the quantum computer has brought a lot of research related to quantum information and its applications in the real world. In this thesis we present a study about a construction of a general criterion of entanglement, in which we can apply it to any system having a Hamiltonian described by spin chains, either bipartite or multipartite. This criterion is based on general observables covariance that may or may not possess terms of interactions between spins. However, this criterion can be easily reduced to the variance, since this is more suitable for use in physical systems. In this way, we can use the magnetic susceptibility and the specific heat as witnesses of entanglement for the criterion, because of their ease of experimental measurements.

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