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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.
351

Chyby a opravy měření atmosférických srážek / Errors and corrections of atmospheric precipitations measurements

Ptáček, Tomáš January 2012 (has links)
The thesis approaches the problem of systematic errors that arise in measuring precipitation. These errors lead to underestimation of total rainfall. Size of losses can reach in our latitudes even tens of percent. The systematic errors that contribute most to the underestimation include losses caused by the rain gauge walls wetting, evaporation losses and losses due to aerodynamic effects on the rain gauge precipitation particles. A major section of the thesis is formed by background research, which deals with the issue of systematic measurement errors precipitation. The background research tackles the lack of literature on this topic in the Czech Republic. In the research section of the thesis, two existing correction methods for estimating the size of systematic errors for the Czechoslovak manual rain gauge Metra (method developed in the 80's by Slovak Hydrometeorological Institute and the method described by the dissertation thesis Radoslav Tihlárik) were applied to data of selected four stations in the Czech Republic (Milešovka, Bedřichov - Přehrada, Čáslav - Nové Město and Svratouch) . The first mentioned method was applied to all stations in the Slovak Republic in the nineties. Nevertheless, it has not been used in the Czech Republic so far. The results show that the Tihlárik method gives...
352

Incertezas e impactos de mudanças climáticas sobre o regime de vazões na Bacia Hidrográfica do Rio Uruguai

Adam, Katiúcia Nascimento January 2016 (has links)
Mudanças climáticas podem afetar a distribuição espacial e temporal das variáveis hidrológicas, tendo como consequências alterações nos regimes de precipitação e vazão dos rios. Aumentos ou reduções no volume de escoamento de uma bacia hidrográfica podem, por exemplo, produzir danos aos ecossistemas, afetar a produção de alimentos, abastecimento de água, navegação e geração de energia. Atualmente buscam-se relações que permitam entender os processos de mudanças climáticas a fim avaliar os impactos e mitigá-los, assim como avaliar as incertezas inerentes ao processo de modelagem hidrológica de tais mudanças. Neste contexto este trabalho apresenta uma metodologia de quantificação e análise de incertezas para estudos de mudanças climáticas, tomando como estudo de caso a bacia hidrográfica do Rio Uruguai (BHRU) com área aproximada de 110,000 Km². Para tanto três fontes de incerteza foram analisadas e comparadas: o modelo hidrológico, técnicas de remoção de viés e modelos climáticos. O modelo hidrológico MGB-IPH foi avaliado quanto ao processo de parametrização, utilizando diferentes períodos de simulação para calibração: (i) Período de calibração 1 – MGB/P1: representando a série completa de observações de 1960-1990 com verificação no período de 1992-1999; (ii) Período de calibração 2 - MGB/P2: calibração em período seco e verificação de período de cheias (iii) Período de calibração 3 – MGB/P3: calibração em período característico de cheias e verificação de período de estiagem. Três diferentes técnicas de remoção de viés foram aplicadas para analisar o grau de incerteza que a escolha de um determinado método de correção pode agregar ao resultado final: (i) RV1 - Técnica de Mapeamento Quantil-Quantil; (ii) RV2 - Técnica de Escalonamento Linear e (iii) RV3 - Técnica Delta change. Os modelos climáticos globais (GMC’s) foram analisados quanto a sua estrutura, comparando projeções de cinco diferentes modelos: MPEH5 (ECHAM5/MPIOM), GFCM21 (GFDL-CM2.1), MRCGCM (MRI-CGCM2.3.2), HADCM3 (UKMO-HadCM3) e NCCCSM (CCSM3). Adicionalmente, também foram analisadas as projeções climáticas de cinco diferentes versões do modelo climático regional (RCM) ETA/CPTEC: CT20, CT40, LOW, MID e HIGH. Inicialmente os resultados das simulações provenientes de cada uma destas fontes foram comparados de maneira isolada e em seguida de maneira combinada. Portanto, a metodologia foi dividida em Etapa (1) e Etapa (2). A Etapa (1) teve por objetivo responder a seguinte pergunta: Qual dentre as fontes de incerteza selecionadas agrega maior variação ao resultado final? Ou seja, qual destas fontes propaga maior incerteza em termos de impactos de mudanças climáticas na BHRU? Os resultados obtidos por cada uma das fontes de incerteza foram comparados em termos de anomalias de vazões médias de longo período (QMLP), máximas e mínimas anuais. Na Etapa (2) foi realizada a análise total de incerteza, ou seja, a análise combinada dos resultados obtidos na Etapa (1). As anomalias de vazões foram apresentadas utilizando as curvas de distribuição acumulada (CDF’s) e a incerteza total expressa pela diferença entre os percentis 5% e 95%. Considerando os resultados obtidos para as vazões médias de longo período (QMLP), as fontes podem ser ordenadas de forma decrescente, em relção ao grau de incerteza que propagam: modelos climáticos globais > modelos climáticos regionais > técnicas de remoção de viés > modelo hidrológico. Para as vazões extremas os RCM’s apresentam as maiores variações de anomalias se comparadas às dos modelos hidrológicos e técnicas de remoção de viés, inclusive para ambos os extremos, máximos e mínimos. Esta variação se dá principalmente, pelos resultados de LOW e MID. Estas informações podem ajudar os gestores e tomadores de decisão no adequado gerenciamento e planejamento dos recursos hídricos sob condições de mudanças climáticas, assim como o entendimento da incerteza associada. / Climate change can affect the spatial and temporal distribution of hydrological variables, with the consequences of changes in precipitation regimes and river flows. Increase or decrease the flow of rivers, for example, can cause damage to ecosystems, affecting food production, water supply, navigation and power generation. Currently seeking to relationships that allow understand climate change processes in order to assess the impacts and mitigate them, and assess the uncertainties inherent in hydrologic modeling process of such climate change. This thesis aimed at the development of a methodology for quantification and analysis of uncertainties for climate change studies in hydrology , taking as a case study the basin of the Uruguay River (BHRU) with a drainage area near 110,000 km². For that three sources of uncertainty were analyzed and compared: the hydrologic model, bias removal techniques and climate models. The hydrological model MGB-IPH was evaluated for parameterization, using different simulation periods for calibration: (i) MGB /P1: full range with calibration period (1960-1990) and validate (1992-1999); (ii) MGB / P2: calibrated in the period of dry and validated in the flood season (iii) MGB/P3: calibrated in the period of floods and validated in the dry season. Three different bias correction methods were applied to analyze the degree of uncertainty that the choice of a particular method of correction can add to the final result: (i) RV1 - Quantil-Quantil Mapping; (ii) RV2 - Linear Scaling, and (iii) RV3 - Delta Change Technique. Global climate models (GMC's) were analyzed for their structure, comparing projections of five different models: MPEH5 (ECHAM5/MPI-OM), GFCM21 (GFDLCM2.1), MRCGCM (MRI-CGCM2.3.2), HADCM3 (UKMO-HadCM3) e NCCCSM (CCSM3). Additionaly, climate projections from five different versions of the regional climate model (RCM) ETA / CPTEC were also analyzed: CT20, CT40, LOW, MID e HIGH. Initially the simulation results from each of the sources of uncertainty were compared individually (single propagation) and then in a combined way (multi propagation). Therefore, the methodology was divided in Step (1) and Step (2). Step (1) aimed to answer: Which of the selected sources of uncertainty adds more variation to the final result? Which of these sources propagates greater uncertainty in terms of impacts of climate change on BHRU? The results for each of the sources of uncertainty were compared in terms of long-term mean flow (QMLP), maximum and minimum annual flow. In Step (2) total uncertainty analysis was performed, therefore the combined analysis of the results obtained in Step (1). The anomalies in discharge were presented using the cumulative distribution function (CDF's) and the total uncertainty expressed by the difference between the percentiles 5% and 95%. Throughout the application of the proposed methodology it was concluded that: (i) for the extremes (maximum and minimum) annual discharges the largest source of uncertainty are the projections of the RCM's, followed by the the bias removal technique and finally the hydrological model; (ii) for the QMLP the largest source of uncertainty are followed global climate models, then the regional climate models. This information can help managers and decision makers in the proper management and planning of water resources under climate change conditions, as well as the understanding of the associated uncertainty.
353

Cálculos de (hiper)polarizabilidades dinâmicas das moléculas de ozônio, dióxido de enxofre, óxido nitroso e dióxido de carbono incluindo correções vibracionais e efeitos de correlação eletrônica

Naves, Emílio Santiago 08 November 2013 (has links)
Submitted by Jaqueline Silva (jtas29@gmail.com) on 2014-09-16T17:01:54Z No. of bitstreams: 2 Naves, Emílio Santiago-2014-tese.pdf: 587232 bytes, checksum: 384bbcad6790ecde844af07f4c8deed9 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Jaqueline Silva (jtas29@gmail.com) on 2014-09-16T17:02:18Z (GMT) No. of bitstreams: 2 Naves, Emílio Santiago-2014-tese.pdf: 587232 bytes, checksum: 384bbcad6790ecde844af07f4c8deed9 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-09-16T17:02:18Z (GMT). No. of bitstreams: 2 Naves, Emílio Santiago-2014-tese.pdf: 587232 bytes, checksum: 384bbcad6790ecde844af07f4c8deed9 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2013-11-08 / This work presents results for the dynamic (hyper)polarizabilities of ozone, sulfur dioxide, nitrous oxide and carbon dioxide molecules, with inclusion of vibrational corrections. The electronic contributions for the properties of interest were computed analytically at the single and double coupled cluster level through response theory. Ozone and sulfur dioxide were studied separately. For both systems, contributions of connected triple excitations were also estimated by the multiplicative correction scheme. The vibrational corrections were calculated by the perturbation theoretical method (PT). The zero-point vibrational average correction, calculated only for ozone and sulfur dioxide, proved to be small. Results also show that the pure vibrational correction is relevant for the following nonlinear optical processes: dc-Pockels effect, intensity dependent refractive index, and dc-Kerr effect. For the ozone molecule the dc-second harmonic generation effect also had a significant pure vibrational correction. In addition, pure vibrational correction was calculated according to a variational methodology proposed by our research group (VAR) for the four systems, and the results were compared with the corresponding PT results. A comparison between PT and VAR results shows that ozone is the system most sensitive to the method, while sulfur dioxide and carbon dioxide are the most well behaved. / Neste trabalho são apresentados resultados para as (hiper)polarizabilidades dinâmicas das moléculas de ozônio, dióxido de enxofre, óxido nitroso e dióxido de carbono, com inclusão de correções vibracionais. As contribuições eletrônicas das propriedades de interesse foram computadas analiticamente através da teoria de resposta no nível coupled cluster com substituições simples e duplas. O ozônio e o dióxido de enxofre foram estudados separadamente. Para ambos os sistemas, as contribuições das substituições triplas conexas também foram estimadas através do esquema de correção multiplicativa. As correções vibracionais foram calculadas por meio dométodo de perturbação teórica (PT). A correção da média vibracional de ponto zero, calculada apenas para o ozônio e o dióxido de enxofre, revelou-se pequena. Os resultados também mostram que a correção vibracional pura é relevante para os seguintes processos ópticos não lineares: efeito dc-Pockels, índice de refração dependente da intensidade e efeito dc-Kerr. Para a molécula de ozônio o efeito de geração de segundo harmônico dc também teve uma correção vibracional pura significativa. Em adição, a correção vibracional pura foi calculada segundo uma metologia variacional proposta pelo nosso grupo de pesquisa (VAR) para os quatro sistemas, e os resultados foram comparados com os respectivos resultados PT. Uma comparação entre os resultados PT e VAR mostra que o ozônio é o sistema mais sensível ao método, ao passo que o dióxido de enxofre e o dióxido de carbono são os mais bem comportados.
354

Policing Postsecondary Education: University Police Legitimacy and Fear of Crime on Campus

Barker, Christina N 01 December 2016 (has links)
Assessing the perceptions that students have of the university police officers charged with ensuring student safety is important to maintaining the overall safety of the campus. The current study sought to assess the relationship between student perceptions of university police and the fear of crime felt by students while on campus. Data collection was conducted through a survey methodology using a convenient sample of students in which a self-report survey was sent to the university email addresses of all students enrolled in a southeastern university (n=260). Through the employment of a scale developed to assess the perceptions of university police legitimacy and a similar scale to assess fear of crime, the results of the study demonstrate a relationship exists between the variables. The relationship strengthens when demographics are controlled for. This study was designed to add to the limited amount of research examining perceptions of university law enforcements.
355

Effective Police Supervision

More, Harry W., Miller, Larry S. 01 January 2015 (has links)
Good police officers are often promoted into supervisory positions with little or no training for what makes a good manager. Effective Police Supervision is a core text used in college-level classes on supervisory practices in criminal justice. This popular book combines behavioral theory with case studies that allow the reader to identify and resolve personal and organizational problems. It provides readers with an understanding of the group behaviors and organizational dynamics, with a focus on effectiveness as well as proficiency, and on how a supervisor can help to create an effective organization. This book is also a vital tool in the preparation of police officers for promotional exams. This revised and updated edition includes new material throughout on police accountability, police involvement with news media, dealing with social media, and avoiding scandals. Each chapter includes important key terms and opens with a case study to illustrate important concepts. / https://dc.etsu.edu/etsu_books/1013/thumbnail.jpg
356

Correctional Rehabilitation and Therapeutic Communities: Reducing Recidivism Through Behavior Change (Routledge Innovations in Corrections)

Pealer, Jennifer A 16 March 2017 (has links)
Drawing on original research on the effectiveness of a therapeutic community (TC) in reducing recidivism among juvenile male offenders, Correctional Rehabilitation and Therapeutic Communities: Reducing Recidivism Through Behavior Change provides a comprehensive review of the current state of drug treatment for the offending population, especially the link between juvenile offending and substance abuse. The book assesses the factors predicting successful completion of treatment as well as the methodological limitation of previous TC program reviews, and suggests policy implication and routes for future research. Using improvements such as multiple outcome criteria, long-term follow-up, matching groups on risk and needs, and the employment of a standardized instrument to measure program quality, Correctional Rehabilitation assesses the degree to which participation in the TC affects antisocial attitudes and reduces delinquency. Readers will explore how TCs can be designed to influence adolescent drug offenders and ultimately reduce recidivism. This book is essential reading for students, researchers, practitioners, and other stakeholders focusing on the development of treatment programs. / https://dc.etsu.edu/etsu_books/1145/thumbnail.jpg
357

MEASURING POLICE OFFICER SELF-EFFICACY FOR WORKING WITH INDIVIDUALS WITH AUTISM SPECTRUM DISORDER

Love, Abigail M. A. 01 January 2019 (has links)
Autism spectrum disorder (ASD) is currently one of the most researched of all childhood developmental disorders and is receiving attention in many domains including popular media, social sciences, education, and medicine. The purpose of this dissertation was to design and provide initial psychometric evidence for a scale that measures police officer self-efficacy for working with individuals with ASD. Psychometric properties of a scale designed to measure knowledge of ASD were also explored. Data from 620 police officers actively serving in the United States were collected in two separate phases. A 13-item scale was created to measure police officer self-efficacy for working with individuals with ASD. Results from both phases indicated that the scale represented a unidimensional construct. Police officer knowledge of ASD was significantly and positively related to self-efficacy. Knowing more about officers’ knowledge and beliefs in their own capabilities to work with individuals with ASD can help inform future police education and training efforts.
358

Radio Dispatch Cognitive Abilities and Working Memory

Buitron, David A 01 June 2017 (has links)
Public safety radio dispatchers incontrovertibly have to manage multiple tasks at any given time, from relaying lifesaving information to field units, to simultaneously overseeing several monitors and keeping up with the radio transmissions in a timely manner. Interestingly, however, the underlying cognitive abilities necessitated for performing such tasks have not been thoroughly investigated. To begin understanding the cognitive faculties that underlie dispatching tasks, we gauged cognitive ability measures relevant to dispatcher duties and introduced Working Memory Capacity (WMC) as underlying the differentiation on performance. The four general dispatcher cognitive factors identified by Peace Officer Standards and Training (POST) literature, were Reasoning, Perceptual, Memory, and Verbal. This study substantiated the relationship that higher WMC had on increased performance of the four factors; WMC was a strong predictor of overall cognitive task accuracy. This study also measured dispatcher abilities detached from any dispatcher-like duties, to better explore the cognitive underpinnings without the confound of dispatcher-like tasks within the measures. High and low WMC group comparisons also revealed accuracy differences in cognitive abilities, task switching costs, and dual-task interference. Overall, this study provides support for WMC’s executive functioning as a key underlying mechanism determining dispatcher cognitive ability level.
359

Best Practices for Controlling Tuberculosis - Training in Correctional Facilities: A Mixed Methods Evaluation

Murray, Ellen Reynolds 01 January 2016 (has links)
According to the literature, identifying and treating tuberculosis (TB) in correctional facilities have been problematic for the inmates and also for the communities into which inmates are released. The importance of training those who can identify this disease early into incarceration is vital to halt the transmission. Although some training has been done by public health authorities for corrections, there is little to no evaluation of such training. The aim of this mixed methods retrospective study was to evaluate the effectiveness of a training to control TB in correctional facilities. The Southeastern National Tuberculosis Center (SNTC) conducted 12 trainings between 2010 and 2014 with custody, medical, and public health staff working in correctional facilities, as well as with TB program staff from health departments. A total of 442 participants quantitatively and qualitatively evaluated the trainings. Gagne-Briggs and tripod models comprised the theoretical framework of the study. Quantitative data were analyzed using descriptive statistics and qualitative data were analyzed thematically. Analysis showed that the usefulness of the training was considered very good to excellent in each of the trainings. Also, many participants stated that they were going to educate others as well, in order to improve the management of TB in their facilities. The results of this study revealed that using systematic training can contribute to promote a more coordinated release of TB-infected inmates into the community, and therefore improve the quality of life of this population group, resulting in the promotion of social change.
360

Optimisation of environmental gamma spectrometry using Monte Carlo methods

Hernández Suárez, Francisco Javier January 2002 (has links)
<p>Dissertation in Environmental Physics to be publicly examined in Häggsalen (Ångström Laboratory), Uppsala University, on Friday, November 8, 2002 at 10:00 am for the degree of doctor of philosophy in Physics. The examination will be conducted in English. </p><p>Gamma spectrometry is one of the tools commonly used for the measurement of various environmental radionuclides. Simultaneous determination of the absolute activity of gamma emitting radiotracers in a wide range of environmental matrices and fractions necessitates proper and accurate evaluation of the sample-to-detector efficiency. Several radiotracers require, in addition, the use of sub-routines for self-absorption corrections. </p><p>Gamma spectrometry is an important and elegant tool for assessing environmental changes. Optimisation of ultra low-level gamma spectrometry for reliable assessment of such changes requires harmonisation of laboratory needs with sampling and site conditions.</p><p>Different aspects of the calculation of sample-to-detector efficiencies using empirical and Monte Carlo approaches are discussed here, including the uncertainties related to the simulation of the performance of different HPGe detectors and the effects of the incomplete collection of charges in Ge-crystals. Various simulation codes for the computation of peak efficiencies in planar and well Ge-detectors have been developed from scratch. The results of the simulations have been tested against experimental data and compared to other simulation results obtained with the Monte Carlo N-Particle code (MCNP). The construction of calibration sources with improved absorption and collimation characteristics have been, also, described in this work. These sources have been especially designed for the efficiency calibration of Ge-detectors at energies below 100 keV. </p><p>Flexible, fully tested and prototype approaches for the evaluation of self-absorption corrections, based on Monte Carlo simulations, are described. Special consideration is given to the problems related to the sample's variability in size, density and composition. Several examples of the absolute and simultaneous determination of environmental multitracers which benefited from self-absorption corrections and the optimised efficiency calibration algorithms are, also, presented and discussed. These examples include, among other things, a comprehensive analysis of the gamma spectrometry of <sup>234</sup>Th in a wide range of matrices and the speciation of several radionuclides in sediments from a hard-water lake.</p>

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