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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.
21

Aplicacao da metodologia fuzzy na quantificacao da probabilidade de erro humano em instalacoes nucleares / Human error probability quantification using fuzzy methodology in nuclear plants

NASCIMENTO, CLAUDIO S. do 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:27:19Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:13Z (GMT). No. of bitstreams: 0 / Neste trabalho foram obtidas estimativas das Probabilidades de Erro Humano (PEH) das ações dos operadores do Reator de Pesquisa IEA-R1 do IPEN, em resposta a uma hipótese de situação de emergência, e realizada uma avaliação dos Fatores Influenciadores do Desempenho Humano (PSF) potencialmente influentes naquelas ações. A avaliação dos PSF foi realizada com a finalidade de classificá-los de acordo com o seu nível de influência nas ações e de determinar o estado atual destes PSF na instalação. Tanto a obtenção das PEH, como também a avaliação dos PSF, foram realizadas por meio do processo de Avaliação por Especialistas, através de entrevistas e questionários. O grupo especialista foi composto a partir dos próprios operadores do Reator IEA-R1. A representação do conhecimento dos especialistas em expressões lingüísticas e a geração de valores que representam o consenso das avaliações do grupo especialista deram-se pelo emprego da Lógica Fuzzy e da Teoria dos Conjuntos Fuzzy. Os valores obtidos para as PEH foram comparados com dados utilizados pela literatura afim e se mostraram satisfatórios para ações similares, corroborando a metodologia proposta como uma boa alternativa a ser empregada em métodos de Análises de Confiabilidade Humana (ACH). / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
22

Zhodnocení kalkulací ve vybrané soukropomoprávní korporaci a návrhy na zlepšení zjjištěného stavu / Assessing the Costing and Calculations Level in the Selected Private Corporation. and Suggestions for its Improvement

Hudečková, Veronika January 2018 (has links)
The diploma thesis is focused on realizing a critical analysis of the current classification level of costs and calculations in a chosen company that deals with custom production. The aim of the work is to propose a solution based on the identified shortcomings that meets the specifics and needs of the company, both for a cost breakdown and a calculations system.
23

Zhodnocení kalkulací ve vybrané soukromoprávní korporaci a návrhy na zlepšení / Evaluation of the Calculations in the Selected Private Company

Kulíková, Andrea January 2021 (has links)
The diploma thesis deals with the analysis and evaluation of calculations in the Vedanta canteen of the company Jitřenka-Zlatá studna s.r.o. The aim of the work is to propose changes that will improve the current situation of the company. The proposals will be based on an analysis of the current state of cost classification, the method of calculation and the calculation system.
24

Kalkulace nákladů ve vybrané firmě / Costing in the Selected Firm

Zelinková, Petra January 2012 (has links)
The Master´s thesis deals with standard costing method and its implementation in service company which especially fixes and varnishes cars. This work is divided into three parts – theoretic, analytic and proposal. The theoretical part deals with the charactersics of costs and methods of calculation, especially standard costing. The analytical part describes the current status of the company in which the method should be implemented. In the design part the process of iplementation is analyzed.
25

Návrhy na zdokonalení řízení nákladů ve vybraném podniku / Proposals to Improving Cost Management in a Selected Company

Klímová, Barbora January 2013 (has links)
The subject of this thesis are the costs of a specific company, their monitoring and ma-nagement. The theoretical part summarizes the information that served as the default resources. These findings have been applied in the practical part, for the selected com-pany. In the final section are formulated suggestions, which should lead to better ma-nagement of the costs.
26

Assessment of calculation methods for Primary Energy Factors : Case Study of Swedish electricity mix

Ferrero Andrés, Javier January 2022 (has links)
The use of the concept of "primary energy" is present in all types of regulations at both European and national level, so that all aspects related to the reduction of energy use and energy efficiency measures speak in terms of primary energy and Primary Energy Factors, necessary for its conversion. The existing consensus on the use of the term is not such in terms of the methodology for calculating the Primary Energy Factors to be adopted, which is the reason for the search for a methodology that acquires the status of global and standard. Using an analytical methodology, this study will analyze and compare the main methods used by agencies and institutions: the Physical Energy Content Method and the Partial Substitution Method, together with another less widely used method, the Exergy Method. The three calculation methodologies will be applied to the case study of the Swedish electricity production mix. The main objective of this thesis is to analyze the advantages and disadvantages of those methodologies, as well as discuss the difficulties of defining some variables such as efficiencies and system boundaries. The results obtained in this study demonstrate the complexity of trying to analyze a system as complex as the energy consumption of a country based on the calculation of a single number or Primary Energy Factor. The system boundaries affect the results. At the same time, the use of the Physical Energy Content Method is discarded because it incurs thermodynamic discrepancies. On the other hand, the use of the Partial Substitution Method and Exergy Method is encouraged, since they reflect more accurately the primary energy consumption, as long as the values of efficiencies that they use are clearly defined and referenced. However, there is a more widespread use of the Physical Energy Content Method in the institutions since the other methods present the great difficulty of establishing a consensus on the energy and exergy efficiencies values adopted. The complexity of choosing a calculation methodology is not only due to the choice of efficiencies but other factors, such as system boundaries, also influence the final results and they have to be reflected in some way. Therefore, it is difficult to decide on a single solution and future studies on other indicators and variables affecting primary energy usage are needed, for instance, CO2 emissions associated with generation technologies.
27

Optimierung von Druckbehältern unterschiedlicher Geometrien und Werkstoffe

Guthmann, Thomas, Engelmann, Frank 10 December 2016 (has links) (PDF)
Einleitung Moderne Simulations- und Berechnungsmethoden, wie beispielsweise die Finite-Elemente-Methode (FEM), erlauben dem Konstrukteur bereits in einer relativ frühen Phase des Entwicklungsprozesses die wesentlichen Eigenschaften des Produktes virtuell am Computer zu analysieren. Die Ergebnisse dieser Berechnungen können anschließend zur zielgerichteten Verbesserung ausgewählter Produkteigenschaften genutzt werden. Der Aufwand für die Optimierung ist dabei in erster Linie von der Komplexität des Produktes abhängig. Produkte, bei welchen die mathematischen Zusammenhänge zwischen den Ein- und Ausgangsparametern bekannt ist, lassen sich oftmals recht einfach analytisch optimieren. Bei komplexen Produkten oder einer großen Anzahl an Einflussparametern lassen sich diese Zusammenhänge in vielen Fällen nicht herleiten, so dass die Optimierung bisher meist nach dem Trial and Error-Verfahren erfolgte. Diese heuristische Vorgehensweise führt durch eine hohe Anzahl an notwendigen Iterationsschleifen zu einem extremen Anstieg der Zeit und der Kosten, wobei die Wiederholungsrate des Entwicklungsprozessschrittes in hohem Maße von der Erfahrung und dem vorhandenen Wissen des Konstrukteurs abhängig ist. Der Einsatz von wissenschaftlichen Optimierungsverfahren, wie beispielsweise der Topologieoptimierung, ermöglicht eine zielgerichtete und weitestgehend automatisierbare Optimierung von komplexen Produkten. Die hohe Komplexität des Produktes ist dabei oftmals nicht auf den ersten Blick ersichtlich. Beispielsweise gestaltet sich die Gewichtsoptimierung von Druckbehältern mit nicht rotationsymmetrischen Querschnitten aufgrund der komplexen Spannungsverläufe schwierig. Grundsätzlich wird bei Leichtbaukonstruktionen versucht, die zur Verfügung stehende Werkstofffestigkeit in den gegebenen Sicherheitsgrenzen voll auszuschöpfen. Hierfür ist es notwendig, die Materialverteilung an dem Kraftverlauf anzupassen. Bei einem mehrachsigen Spannungszustand, wie er bei den Druckbehältern mit komplexen Geometrien vorliegt, bestehen zwischen der Materialverteilung und den Spannungsverläufen über die Geometrie komplexe Zusammenhänge, so dass für die optimale Materialverteilung keine allgemeingültige triviale Lösung existiert.
28

Análise de fluxo de carga eletrônica em modos vibracionais / Analysis of electronic charge flux in vibrational modes

Tiago Quevedo Teodoro 19 February 2013 (has links)
Diversas metodologias foram desenvolvidas nas últimas décadas para cálculo de propriedades que representassem quantitativamente a distribuição de carga eletrônica de forma mais simplista. A mais básica destas propriedades é chamada de carga atômica. Contudo, não havendo unanimidade quanto à utilização de um formalismo de cálculo de carga para situações abrangentes de estudo, há a necessidade de trabalhos voltados para uma análise comparativa entre as respostas destes formalismos em termos de carga atômica e parâmetros derivados. Assim, fez-se nesta dissertação uma investigação sobre valores de carga atômica e propriedades dinâmicas relacionadas, com importância em estudos sobre movimentos vibracionais em moléculas, como fluxo de carga e fluxo de dipolo, obtidos com os formalismos de cálculo de carga de Mulliken, NPA, CHELPG e QTAIM. Neste trabalho também se avaliou o efeito da escolha do método de cálculo, como Hartree-Fock e métodos que incluem correlação eletrônica (MP2, MP4(SDQ) e CCSD), e do conjunto de funções de base, através de funções como cc-pVDZ, cc-pVTZ e cc-pVQZ, sobre estas propriedades dinâmicas. Os sistemas analisados incluíram moléculas diatômicas e triatômicas lineares (HF, HCl, LiH, NaH, NaCl, LiF, NaF, LiCl, BF, AlF, BeO, MgO, CO, ClF, CO2, CS2, OCS, HCN e HNC) formadas por ligações de caráter variado, desde altamente iônicas até covalentes e incluindo ligações múltiplas. Também foram estudadas moléculas de clorofluorometanos (CH4, CH3Cl, CH3F, CH2Cl2, CH2F2, CH2ClF, CHCl3, CHF3, CHCl2F, CHClF2, CCl2F2, CClF3, CFCl3, CCl4, e CF4) para observação do efeito da troca de substituintes nas propriedades citadas. Pelos resultados obtidos, pode-se afirmar que apenas os formalismos NPA e QTAIM apresentam bom comportamento quanto à convergência em relação ao método de cálculo e/ou tamanho do conjunto de funções de base utilizados no estudo do fluxo de carga. Entretanto, apenas os valores QTAIM são consistentes com certas considerações químicas fundamentais, como fluxos de carga tendendo a zero durante o estiramento de ligações de predominante caráter iônico, em moléculas com estruturas próximas à geometria de equilíbrio. As cargas e seus fluxos obtidos com Mulliken apresentaram alta dependência e problemas de convergência com a escolha da função de base, além de valores incoerentes em alguns sistemas. Por sua vez, CHELPG não se mostrou adequado à aplicação da aproximação finita de dois pontos na obtenção dos valores numéricos de fluxos de carga. A análise da resposta destas propriedades à troca de substituintes em moléculas de clorofluorometanos seguiu destacando positivamente QTAIM em relação aos outros formalismos. Enquanto CHELPG demonstrou oscilações inconsistentes em gráficos destes valores em função do número de átomos de cloro e/ou flúor, NPA e Mulliken se mostraram sensíveis à troca de substituintes, entretanto, os valores de fluxo de carga observados em alguns casos estão em desacordo com a tendência esperada na troca de átomos de hidrogênio por átomos de cloro ou flúor. / Several methodologies were developed in the last few decades in order to obtain a property which could represent quantitatively electronic charge distributions in a simple way. The fundamental quantity in this treatment is called atomic charge. However, as long as there is not an agreement about the most indicated method to determine atomic charges for general systems or responses under study, it is necessary to analyze, comparatively, how these methods behave in given situations and how the values derived from them respond in each case. Hence, an investigation including charges and related quantities as charge flux and atomic dipole flux, which are of interest to vibrational analysis, was done by means of values resulting from four formalisms, that are, Mulliken, NPA, CHELPG and QTAIM. In this study were also evaluated the changes in such dynamic properties when the calculations are done by means of different methods, as Hartree-Fock and methods that include electron correlation (MP2, MP4(SDQ) and CCSD) and, with different basis sets as cc-pVDZ, cc-pVTZ and cc-pVQZ. The systems analyzed were diatomic and linear triatomic molecules (HF, HCl, LiH, NaH, NaCl, LiF, NaF, LiCl, BF, AlF, BeO, MgO, CO, FCl, CO2, CS2, OCS, HCN and HNC) including diverse bonding character, such as highly ionic or covalent bonds along with multiple bonds. Also, charge and charge flux parameters in chlorofluoromethane molecules (CH4, CH3Cl, CH3F, CH2Cl2, CH2F2, CH2ClF, CHCl3, CHF3, CHCl2F, CHClF2, CCl2F2, CClF3, CFCl3, CCl4 and CF4) were studied to analyze the effects in these properties during the exchange of substituent atoms. Considering the data obtained, one can infer that only NPA and QTAIM formalisms result in satisfactory convergence patterns with chosen methods and/or basis set sizes during the determination of charge and charge flux values. However, only QTAIM charge fluxes seem to follow certain chemical considerations, as low values for charge flux in a bond enlargement in systems with a predominant ionic character close to their equilibrium geometry. The Mulliken formalism shows high dependence and convergence issues in basis set size increments, as well as some inconsistent values. On other hand, CHELPG formalism is not suited to the finite approach for numerical derivatives in its two-point version. The study of substituent effects in chlorofluoromethanes reinforces the performance of QTAIM when compared to other formalisms. While CHELPG returned inconsistent oscillations in plots against the number of chlorine/fluorine atoms, NPA and Mulliken exhibited some sensibility with the change of substituent, though the flux values observed in a few cases are in disagreement with the tendencies expected when the hydrogen atoms are switched by chlorine or fluorine atoms.
29

Matematické a fyzikální aplikace vícerozměrného Riemannova integrálu / The multiple Riemann integral and its applications in mathematics and physics

BRDLÍK, Pavel January 2015 (has links)
The diploma thesis surveys the problematics of multidimensional Riemann integral. The goals of the thesis are, firstly, to provide a clear summary of the Multidimensional Riemann Integration Theory, secondly, to describe the basic calculation methods on carefully chosen examples, and, thirdly, to demonstrate its practical use in mathematics and natural sciences in general.
30

Estudo sobre a metodologia de apuração da taxa DI-Cetip e seus impactos no mercado

Sá, Anderson Ricardo Ubinha de 12 August 2016 (has links)
Submitted by Anderson Ricardo Ubinha de Sá (anderson.ubinha@yahoo.com.br) on 2016-09-05T21:29:18Z No. of bitstreams: 1 Dissertação Final - Anderson Ricardo Ubinha de Sá vf.pdf: 6749863 bytes, checksum: bd865f83f290dfc8a997497024fa3e32 (MD5) / Approved for entry into archive by Renata de Souza Nascimento (renata.souza@fgv.br) on 2016-09-06T17:20:49Z (GMT) No. of bitstreams: 1 Dissertação Final - Anderson Ricardo Ubinha de Sá vf.pdf: 6749863 bytes, checksum: bd865f83f290dfc8a997497024fa3e32 (MD5) / Made available in DSpace on 2016-09-06T17:23:02Z (GMT). No. of bitstreams: 1 Dissertação Final - Anderson Ricardo Ubinha de Sá vf.pdf: 6749863 bytes, checksum: bd865f83f290dfc8a997497024fa3e32 (MD5) Previous issue date: 2016-08-12 / O objetivo deste trabalho é comparar as metodologias anterior e atual da taxa DI-Cetip e indicar as suscetibilidades de cada procedimento. Por meio da geração de operações com taxas e volumes coerentes com o histórico, foi possível comparar ambas as metodologias e outras possíveis seis propostas apresentadas, além de identificar as magnitudes das diferenças dos resultados das apurações. São sugeridas melhorias a serem implementadas, como o delay na divulgação das informações, a exclusão total de outliers, a redução dos pesos das taxas extremas de forma simétrica, além de uma alternativa semelhante à taxa LIBOR, que mitigaria algumas das questões apontadas e seria mais adequada devido à redução drástica de negócios válidos para o cálculo. / The objective of this study is to compare the previous and current methodologies of DI-Cetip rate and indicate the susceptibilities of each procedure. By generating trades with rates and volumes according history, it was possible to compare both methodologies and other possible six proposals and identify the magnitudes of the differences in calculations. Improvements are suggested to be implemented, such as the delay in the disclosure of information, the total exclusion of outliers, reducing the weights of the extreme rates symmetrically, and an alternative like LIBOR, which would mitigate some of the issues raised and would be appropriate due to the drastic reduction of valid trades for the calculation.

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