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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.
1

Biomagnetic field measurements and their interpretation using the dipole in a sphere model

Janday, B. S. January 1987 (has links)
No description available.
2

Estudo da responsabilidade social do Instituto de Pesquisas Energéticas e Nucleares de São Paulo (IPEN/CNEN - SP) / Study of social responsibility of the Nuclear and Energy Research Institute of São Paulo (IPEN/CNEN-SP)

Rita de Cássia Mutarelli 22 May 2014 (has links)
Ao longo dos anos, a evolução do conceito socioambiental tem se solidificado por meio de programas, conferências e diversas atividades que ocorrem no Brasil e no mundo. A sustentabilidade e a responsabilidade social passaram a ser parte integrante do cotidiano das organizações. O Instituto de Pesquisas Energéticas e Nucleares (IPEN) 1, que é o foco desse trabalho tem como parte da sua missão o compromisso com a melhoria da qualidade de vida da população brasileira e com base na missão do IPEN e na falta de instrumentos de avaliação de ações socioambientais, este trabalho tem como objetivo propor um instrumento que avalie a responsabilidade social e sirva como uma opção metodológica fortemente comprometida com o aprimoramento do Instituto. Por meio de indicadores e dimensões, construiu-se uma metodologia que busca avaliar a responsabilidade social e identificar tanto os pontos fortes como os fracos. Essa metodologia foi aplicada ao IPEN, e os resultados apresentados nesse trabalho identificaram aspectos positivos com respeito às suas ações para com o público interno e pontos a serem melhorados com relação ao seu público externo. Os resultados foram satisfatórios, no entanto, esse trabalho poderá ter uma continuidade, pois o tema é amplo e não se esgota nesse estudo. Por meio dessa pesquisa, os gestores do IPEN poderão identificar ações socioambientais viáveis que possam ser implementadas no Instituto. / Over the years, the socio-environmental concept has grown through programs, conferences and several activities that have been held in Brazil and worldwide. Sustainability and social responsibility are now an integral part of everyday life of organizations The Instituto de Pesquisas Energéticas e Nucleares (IPEN)2, which is the focus of this research, is committed to the improvement of Brazilian quality of life. Based on IPEN´s mission, and due to the lack of tools for assessing socio-environmental actions, this research aims to propose an assessment tool for social responsibility, which may also be a methodological resource committed to the improvement of the Institute. Through indicators and dimensions, a methodology to assess social responsibility and identify both strengths and weaknesses was designed. The methodology was administered to IPEN, and the results demonstrated positive aspects regarding actions towards the internal publics and negative aspects towards the external publics that require improvement. The results obtained were satisfactory. Nevertheless, as the subject of this study is a broad theme, further studies are suggested. IPEN´s board may use the results of this research as a tool to help them identify feasible socio-environmental actions to be implemented in the institute.
3

Defining Cheating Using Multiple Models

Dowdle, Krista Joy 11 August 2022 (has links)
Extradyadic romantic behavior in committed relationships, referred to here as "cheating," is a common occurrence. For the purposes of this study, we define cheating as romantic or sexual behaviors that occur outside of a committed romantic relationship and that violate the expectations of the relationship. This definition can be broken down into two parts: the behavior that occurred and the judgment of whether that behavior constitutes cheating. Using a large sample (N = 1,020), we tested a measure that conceptualized cheating as composing explicit behaviors, categorical judgment of behaviors, and dimensional judgment of behaviors. Fit statistics were mixed and we included suggested modifications. Biological sex was a significant modifier for each factor, with men endorsing significantly more explicit behaviors and women rating more behaviors as cheating and more serious. We found no significant differences in explicit behaviors or categorical judgments based on age, but older generations rated behaviors as more serious. Having experienced cheating in a relationship (as transgressor and/or victim) resulted in rating more behaviors as cheating than those who had no experience with cheating. With modifications, our measure is promising in assisting with the understanding of cheating and expectations in relationships.
4

Measuring the complexity of teachers' enactment of practice for equity: A Rasch model and facet theory-based approach

Chang, Wen-Chia Claire January 2017 (has links)
Thesis advisor: Larry H. Ludlow / Preparing and supporting teachers to enact teaching practice that responds to diversity, challenges educational inequities, and promotes social justice is a pressing yet daunting and complex task. More research is needed to understand how and to what extent teacher education programs prepare and support teacher candidates to enhance the achievement of all learners while challenging systematic inequity (Cochran-Smith, Ell, Ludlow, Grudnoff, & Aitken, 2014). One piece of empirical evidence needed is a measure that captures the extent to which teachers enact teaching practice for equity. This study developed an instrument – the Teaching Equity Enactment Scenario Scale (TEES) - to measure the extent of equity-centered teaching practice by applying Rasch measurement theory (Rasch, 1960) and Guttman’s facet theory (Borg & Shye, 1995). The research question addressed whether the TEES scale can measure teachers’ self-reported enactment of practice for equity in a reliable, valid, and authentic manner. This study employed a three-phase design, comprising an extensive process of item development, a pilot study and a final full-scale administration. Fifteen scenario-style items were developed to capture the enactment levels of six interconnected principles of teaching practice for equity. Using the Rasch rating scale model the outcome was a 15-item TEES scale that reliably and validly measures increasing levels of teaching practice for equity progressing through low, moderate, and high levels of enactment. The distribution of the scenarios confirmed their hypothesized order and the instrument development principles of Rasch measurement - unidimensionality, variation and a hierarchical order of the items, as well as a uniform continuum defining the construct. The scale also provides meaningful interpretations of what a raw score means regarding one’s equity-centered teaching practice. The overall findings suggest that the novel approach of combining Rasch measurement and facet theory can be successful in developing a scenario-style scale that measures a complex construct. Moreover, the scale can provide the evidence needed in research on preparing and supporting teachers to teach with a commitment to equity and social justice.
5

Development of a descriptive system for patient experience

Singh, Jeshika January 2018 (has links)
Efficient allocation of public resources requires identification, measurement and quantification of costs and benefits of alternative programs. Patient reported outcomes (PROs) are routinely incorporated into economic evaluations of health technologies, but patient experience is often overlooked. This thesis aims to develop a descriptive system for patient experience that can be valued and used to inform economic evaluation. The generation and selection of items is key in the development of any PRO measure. The thesis provides a contemporary overview of recommended methods and those actually used by instrument developers. Frequently a staged approach is used to establish dimensions first, using exploratory factor analysis, followed by item selection using item response theory (IRT), Rasch or structural equation modelling (SEM). I demonstrate the use of different methods for item selection and its underlying mechanics, followed by comparison of the methods. An existing patient dataset, the Inpatient survey (2014) that collected information on nearly 70 aspects of healthcare delivery from NHS users was used. Logistic regression analyses were applied with respondents' rating of overall patient experience specified as dependent variable. Advanced statistical analyses focussed mostly on patients who had an operation or procedure. Latent construct or dimensions were derived and measurement model was confirmed using confirmatory factor analysis. IRT and factor analysis were employed in each one-factor model for item selection. Regression analyses identified many significant variables but most overlapped conceptually. An 11 and 8 factor model for patients with A&E and planned admissions respectively was determined. A generalised partial credit model and a factor analysis model identified different items to include in each dimension. Broadly the items identified by different methods related to respect, comfort and clear communication to patients. This thesis presents descriptive systems for patient experience that is amenable to valuation. It also demonstrates that different patient experience instruments are generated based on patient population used and item selection technique adopted.
6

Theory of measurement-based quantum computing

de Beaudrap, Jonathan Robert Niel January 2008 (has links)
In the study of quantum computation, data is represented in terms of linear operators which form a generalized model of probability, and computations are most commonly described as products of unitary transformations, which are the transformations which preserve the quality of the data in a precise sense. This naturally leads to unitary circuit models, which are models of computation in which unitary operators are expressed as a product of "elementary" unitary transformations. However, unitary transformations can also be effected as a composition of operations which are not all unitary themselves: the one-way measurement model is one such model of quantum computation. In this thesis, we examine the relationship between representations of unitary operators and decompositions of those operators in the one-way measurement model. In particular, we consider different circumstances under which a procedure in the one-way measurement model can be described as simulating a unitary circuit, by considering the combinatorial structures which are common to unitary circuits and two simple constructions of one-way based procedures. These structures lead to a characterization of the one-way measurement patterns which arise from these constructions, which can then be related to efficiently testable properties of graphs. We also consider how these characterizations provide automatic techniques for obtaining complete measurement-based decompositions, from unitary transformations which are specified by operator expressions bearing a formal resemblance to path integrals. These techniques are presented as a possible means to devise new algorithms in the one-way measurement model, independently of algorithms in the unitary circuit model.
7

Theory of measurement-based quantum computing

de Beaudrap, Jonathan Robert Niel January 2008 (has links)
In the study of quantum computation, data is represented in terms of linear operators which form a generalized model of probability, and computations are most commonly described as products of unitary transformations, which are the transformations which preserve the quality of the data in a precise sense. This naturally leads to unitary circuit models, which are models of computation in which unitary operators are expressed as a product of "elementary" unitary transformations. However, unitary transformations can also be effected as a composition of operations which are not all unitary themselves: the one-way measurement model is one such model of quantum computation. In this thesis, we examine the relationship between representations of unitary operators and decompositions of those operators in the one-way measurement model. In particular, we consider different circumstances under which a procedure in the one-way measurement model can be described as simulating a unitary circuit, by considering the combinatorial structures which are common to unitary circuits and two simple constructions of one-way based procedures. These structures lead to a characterization of the one-way measurement patterns which arise from these constructions, which can then be related to efficiently testable properties of graphs. We also consider how these characterizations provide automatic techniques for obtaining complete measurement-based decompositions, from unitary transformations which are specified by operator expressions bearing a formal resemblance to path integrals. These techniques are presented as a possible means to devise new algorithms in the one-way measurement model, independently of algorithms in the unitary circuit model.
8

Random or fixed testlet effects : a comparison of two multilevel testlet models

Chen, Tzu-An, 1978- 10 December 2010 (has links)
This simulation study compared the performance of two multilevel measurement testlet (MMMT) models: Beretvas and Walker’s (2008) two-level MMMT model and Jiao, Wang, and Kamata’s (2005) three-level model. Several conditions were manipulated (including testlet length, sample size, and the pattern of the testlet effects) to assess the impact on the estimation of fixed and random effect parameters. While testlets, in which items share the same stimulus, are common in educational tests, testlet item scores violate the assumption of local item independence (LID) underlying item response theory (IRT). Modeling LID has been widely discussed in previous studies (for example, Bradlow, Wainer, and Wang, 1999; Wang, Bradlow, and Wainer, 2002; Wang, Cheng, and Wilson, 2005). More recently, Jiao et al. (2005) proposed a three-level MMMT (MMMT-3r) in which items are modeled as nested within testlets (level two) and then testlets are nested with persons (level three). Testlet effects are typically modeled as random in previous studies involving LID. However, item effects (difficulties) are commonly modeled as fixed under IRT models: that is, persons with the same ability level are assumed to have the same probability of answering an item correctly. Therefore, it is also important that a testlet effects model permit modeling of item effects as fixed. Moreover, modeling testlet effect as random implies testlets are being sampled from a larger population of testlets. However, as with item effects, researchers are typically more interested in a particular set of items or testlets that are being used in an assessment. Given the interest of the researcher or psychometrician using a testlet response model, it seems more useful to use a testlet response model that permits modeling testlets effects as fixed. An alternative MMMT that permits modeling testlet effect as fixed and/or randomly varying has been proposed (Beretvas and Walker, 2008). The MMMT-2f and MMMT-2r models treat testlet effects as item-set-specific but not person-specific. However, no simulation has been conducted to assess how this proposed model performs. The current study compared the performance of the MMMT-2f, MMMT-2r with that of the MMMT-3r. Results of the present simulation study showed that the MMMT-2r yielded the best parameter bias in estimation on fixed item effects, fixed testlet effects, and random testlet effects for conditions with nonzero equal pattern of random testlet effects’ variance even when the MMMMT-2r was not the generating model. However, random effects estimation did not perform well when unequal random testlet effects’ variances were generated. Fit indices did not perform well either as other studies have found. And it should be emphasized that model differences were of very little practical significance. From a modeling perspective, MMMT-2r does allow the greatest flexibility in terms of modeling testlet effects as fixed, random, or both. / text
9

An evaluation of item difficulty and person ability estimation using the multilevel measurement model with short tests and small sample sizes

Brune, Kelly Diane 08 June 2011 (has links)
Recently, researchers have reformulated Item Response Theory (IRT) models into multilevel models to evaluate clustered data appropriately. Using a multilevel model to obtain item difficulty and person ability parameter estimates that correspond directly with IRT models’ parameters is often referred to as multilevel measurement modeling. Unlike conventional IRT models, multilevel measurement models (MMM) can handle, the addition of predictor variables, appropriate modeling of clustered data, and can be estimated using non-specialized computer software, including SAS. For example, a three-level model can model the repeated measures (level one) of individuals (level two) who are clustered within schools (level three). Limitations in terms of the minimum sample size and number of test items that permit reasonable one-parameter logistic (1-PL) IRT model’s parameters have not been examined for either the two- or three-level MMM. Researchers (Wright and Stone, 1979; Lord, 1983; Hambleton and Cook, 1983) have found that sample sizes under 200 and fewer than 20 items per test result in poor model fit and poor parameter recovery for dichotomous 1-PL IRT models with data that meet model assumptions. This simulation study tested the performance of the two-level and three-level MMM under various conditions that included three sample sizes (100, 200, and 400), three test lengths (5, 10, and 20), three level-3 cluster sizes (10, 20, and 50), and two generated intraclass correlations (.05 and .15). The study demonstrated that use of the two- and three-level MMMs lead to somewhat divergent results for item difficulty and person-level ability estimates. The mean relative item difficulty bias was lower for the three-level model than the two-level model. The opposite was true for the person-level ability estimates, with a smaller mean relative parameter bias for the two-level model than the three-level model. There was no difference between the two- and three-level MMMs in the school-level ability estimates. Modeling clustered data appropriately; having a minimum total sample size of 100 to accurately estimate level-2 residuals and a minimum total sample size of 400 to accurately estimate level-3 residuals; and having at least 20 items will help ensure valid statistical test results. / text
10

A LOGÍSTICA DE TRANSPORTE E AS CADEIAS AGROPECUÁRIAS AVÍCOLA E SUINÍCOLA, IMPACTO SOCIAL E ECONÔMICO NO DESENVOLVIMENTO LOCAL DO MUNICÍPIO DE TOLEDO - PR / Transport Logistics and Aviculture and Swine Culture Agricultural Chains, Social and Economical Impact in the Local Development in the Municipality of Toledo PR

Manfroi, Armando Staudt 24 March 2008 (has links)
The economy in the west of the State of Paraná is market by the strong participation of the agricultural activities; much from what is produced either in the State or in the country is native of this region. Particularly for the Municipality of Toledo, the aviculture and swine culture are the main agricultural. These are directly mediated by the activities of transport logistics, which play the important and directly responsible role by the appropriate development of the agricultural. Thus, this search shows the development of a model which aims to measure the impacts caused by the transport logistics in the aviculture and swine culture. Thus, it has been attempted to answer what the economical and social impacts are that the transport logistics cause on birds and swine chains, that justified by the characteristic of importance which the transport activity has for the activities, due to the fact that it is treated of an activity that provides the connection among several initial productive stages. The data collection has contemplated the search for information in local public organs and private companies which are directly connected to the activity; this information were fundamental to the is referred to the construction of indicators about the studied activities. From the collected data, it has been developed a matrix of analysis from this data which shows the direct relation among the global numbers in the Municipality (e.g., the total of employment in the Municipality in relation to the total employment from the bird and swine chains). It has been evident during the search the essential role of the transport logistics, and it can be claimed that there is a high level of dependence of the activities that involve bird and swine production in the transport logistical services, thus, any alteration in the transport configuration may bring direct consequences to aviculture and swine culture, interfering in the results and in the production. It is believed that this study has contributed to the explanation of the importance of the transport activities in the context of birds and swine production for the Municipality, and indirectly for the local economical and social development. / A economia do oeste do estado do Paraná é marcada pela forte participação das atividades agropecuárias. Muito do que se produz no estado e no país é oriundo dessa região. Em específico para o município de Toledo, a avicultura e a suinocultura são as principais atividades agropecuárias. Estas são diretamente mediadas pela logística de transporte, que assume papel indispensável e diretamente responsável pelo desenvolvimento adequado destas. Assim esta pesquisa apresenta o desenvolvimento de um modelo que objetiva mensurar os impactos causados pela logística de transportes nas atividades, avícola e suinícola. Dessa forma se buscou responder quais são os impactos econômicos e sociais que a logística de transportes causa nas cadeias de aves e suínos, isso justificado pela característica de importância que os transportes têm para estas cadeias produtivas, visto que se trata de uma atividade que proporciona a ligação entre as diversas etapas produtivas iniciais. A coleta de dados contemplou a busca de informações em órgãos públicos e empresas privadas locais com ligação direta à atividade. Essas informações foram fundamentais para a construção de indicadores sobre as atividades estudadas. A partir dos dados coletados se desenvolveu uma matriz de análise desses dados que apresentam a relação direta entre os números das atividades de avicultura e suinocultura, comparadas com números globais do município (como por exemplo, o total de empregos do município em relação com o total de empregos das cadeias de aves e suínos). Ficou claro durante a pesquisa, o papel fundamental da logística de transporte, e pode-se dizer que existe um alto grau de dependência das atividades que envolvem a produção de aves e suínos dos serviços logísticos de transporte. Dessa forma, qualquer alteração na configuração dos transportes pode trazer conseqüências diretas à avicultura e suinocultura, interferindo nos resultados e na produção. Acredita-se que este estudo contribuiu para o esclarecimento da importância das atividades de transportes no contexto da produção de aves e suínos para o município, e indiretamente para o desenvolvimento econômico e social local.

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