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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.
71

Vyrovnanost vybraných fotbalových lig v Evropě, jejich vývoj a porovnání / Competitive Balance the of selected football leagues in Europe, their development and comparison

Mráček, Václav January 2012 (has links)
Title: Competitive Balance of the selected football leagues in Europe, their development and comparison. Goals: Determining the competitive balance in the six top European football competitions. This is a Czech Gambrinus liga, Dutch Eredivisie, German Bundesliga, Austrian Bundesliga, Ukrainian Premier liha Hungarian OTP liga, compare to competition and an outline of the development trend. Methods: The standard deviation of percentage wins, correlation coefficient, the presentation of results based on percentages, graphs, trends. Results: All results are presented in the analytical part of the work, verify predetermined hypotheses and are an important source of comparison for each event and outline trends. Keywords: Competition, equilibrium, European football league, football league, static balance, dynamic balance, season, club, reform, UEFA, sport, decreased balance, standard deviation, correlation coefficient.
72

Satisficing solutions for multiobjective stochastic linear programming problems

Adeyefa, Segun Adeyemi 06 1900 (has links)
Multiobjective Stochastic Linear Programming is a relevant topic. As a matter of fact, many real life problems ranging from portfolio selection to water resource management may be cast into this framework. There are severe limitations in objectivity in this field due to the simultaneous presence of randomness and conflicting goals. In such a turbulent environment, the mainstay of rational choice does not hold and it is virtually impossible to provide a truly scientific foundation for an optimal decision. In this thesis, we resort to the bounded rationality and chance-constrained principles to define satisficing solutions for Multiobjective Stochastic Linear Programming problems. These solutions are then characterized for the cases of normal, exponential, chi-squared and gamma distributions. Ways for singling out such solutions are discussed and numerical examples provided for the sake of illustration. Extension to the case of fuzzy random coefficients is also carried out. / Decision Sciences
73

Porovnání účinnosti návrhů experimentů pro statistickou analýzu úloh s náhodnými vstupy / Performance comparison of methods for design of experiments for analysis of tasks involving random variables

Martinásková, Magdalena January 2014 (has links)
The thesis presents methods and criteria for creation and optimization of design of computer experiments. Using the core of a program Freet the optimized designs were created by combination of these methods and criteria. Then, the suitability of the designs for statistical analysis of the tasks vith input random variables was assessed by comparison of the obtained results of six selected functions and the exact (analytically obtained) solutions. Basic theory, definitions of the evaluated functions, description of the setting of optimization and the discussion of the obtained results, including recommendations related to identified weaknesses of certain designs, are presented. The thesis also contains a description of an application that was created to display the results.
74

Určení prostorových vztahů jeřábové dráhy / Deformation Surveying of Crane Track

Molčan, Vladimír January 2014 (has links)
The main theme of this master thesis is the design of technological process measurement and processing of measured data entered crane tracks to determine the geometric parameters of these crane tracks. Diploma thesis further describes the procedure for testing and possible rectification surveying equipment and instrumentation. The thesis is divided of 7 parts, contains 31 images, 4 graphs, 44 tables and 13 attachments. The theoretical part of this thesis contains information about several types of cranes, methods of measurement and processing, as well information on legal and technical regulations related to this topic of the thesis. The fourth and fifth parts of this thesis provides information on selected crane tracks on which the measurements were taken, the choice of methods of measurement, processing technique and the results obtained. The final part of the thesis includes evaluation of the results obtained, comparing methods of measurement, processing, evaluation and design of a technique of determining the geometric parameters of crane tracks.
75

Racionalizace výroby a kontroly vřeten vodárenských armatur / Redeployment and verification spindles water supply river armours

Jelínek, Norbert January 2009 (has links)
Solving problems of production and calibration spindles water supply river armours by the help of method SPC. Analysis capability of gauge by the help of methodists MSA-Cg,Cgk. Evaluation capability of machanical abnd digital outside micrometer. Verification limiting deviation of micrometrical screw in among - calibration interval. Attestation capability of machine and of the process. Construction of regulation diagram. Project of new control instruments. Technically-economic evaluation:savings 110 560,00Kč, profitability 764,85%, economic return 0,13 year. Successful application of methodists SPC attested by document about adjustability of the process.
76

Kontroll av zinkskikt på monterat räckesmaterial / Check of zinc coating thickness on erected safety barriers

Fathi, Shida January 2014 (has links)
Kontroll av zinkskikt på monterat räckesmaterial som görs ute i fält saknar en fastställd metod. Zinktjockleken har ett minimum tjocklekskrav enligt den svenska standarden ISO 1461:2009, som bestäms av dimensionen på ståldetaljens tjocklek. Trafikverket begär att med hjälp av detta examensarbete kunna begränsa antal mätningar på plats, då kan det ta allt för mycket tid och arbetsresurser i fall det skulle behövas kontroll av väg-och bro räckesanläggningar från beställaren. Sannolikhetsläran och stickprov i statistik hjälper oss att begränsa antalet mätningarna på skyddsanordningarna som görs ute i fält. Med hjälp av normalfördelning kommer man fram till den efter strävade metoden, som med en rimlig arbetsinsats ger en rättvisbild av skikttjockleken på monterat räckesmaterial. Vid variation av varmförzinkaren på vägräckesanläggningar undersöker man varje leverantörs räckesdel för sig, alltså man mäter zinktjockleken på en varmförzikare för sig, kontrollerar zinkskiktstjockleken på de och tar slutsatser sedan går man vidare till nästa tillverkare. Om vägräckena är mindre än 30 stycken mäter man zinktjockleken på respektive anläggning. För beräkning av zinkskiktstjockleken på monterad räckesmaterial börjar man med 30 mätningar och användning av den centrala gränsvärde satsen för att approximera till normalfördelning och analysera resultatet. Det slutliga resultatet av examensarbetet är ett Excelprogram med inmatade formler. Excel programmet är ett hjälpmedel för framtagning av 95 % konfidensintervall. Med hjälp av detta intervall kan man ta slutsatser om zinkskiktet på vägräckena uppfyller kravet eller inte och kunna komma fram till ett resultat. Om kravet ligger i intervallet eller store än intervallet är materialet godkänt. / Control of zinc coating on assembled railing materials made on site lacks a common methodology. Zinc coating should have a minimum thickness requirements according to the Swedish standard ISO 1461:2009, which is determined by the dimension of the steel thickness. Trafikverket expects that with help from this thesis it could limit the number of measurements on site, otherwise it will take too much time and labor resources, in case control of road and bridge railing systems are required from the customer.  Probabilities and sampling in statistics helps us to limit the number of measurements of the protective devices that are made in the field. Using normal distribution, one arrive at the element of method that with reasonable effort gives a fair picture of the layer thickness of the assembled railing materials. Upon variation of the galvanizers on road barrier systems, each part is investigated separately by measuring zinc thickness of a galvanizers, checking the zinc coating thickness on them, take conclusions and later on investigate the next manufacturer. If a crash barrier is less than 30 pieces, the zinc coating thickness is measured at each facility by itself. For calculation of the zinc coating thickness on a mounted railing material one begins with 30 measurements and the use of the central limit theorem to approximate it to normal distribution and analyze the results. The final result of the thesis is an Excel program with input formulas. The Excel program is a tool for producing 95% confidence interval. Using this interval, one can make conclusions that if the zinc coating on a crash barrier fulfills the requirement or not and later on be able to come up with a result. If the requirement is in the interval or larger than the interval, the material is approved.
77

[pt] EFEITO DA ESTIMAÇÃO DOS PARÂMETROS SOBRE O DESEMPENHO CONJUNTO DOS GRÁFICOS DE CONTROLE DE X-BARRA E S / [en] EFFECT OF PARAMETER ESTIMATION ON THE JOINT PERFORMANCE OF THE X-BAR AND S CHARTS

LORENA DRUMOND LOUREIRO VIEIRA 09 July 2020 (has links)
[pt] A probabilidade de alarme falso, alfa, dos gráficos de controle de processos depende dos seus limites de controle, que, por sua vez, dependem de estimativas dos parâmetros do processo. Esta tese apresenta inicialmente uma revisão dos principais trabalhos sobre o efeito dos erros de estimação dos parâmetros do processo sobre alfa quando se utiliza o gráfico de X e S individualmente e em conjunto. O desempenho dos gráficos é medido através de medidas de desempenho (número médio de amostras até o sinal, taxa de alarme falso, distribuição do número de amostras até o sinal, que, em geral, são variáveis aleatórias, função dos erros de estimação. Pesquisas recentes têm focado nas propriedades da distribuição condicional do número de amostras até o sinal, ou ainda, nas propriedades da distribuição da taxa de alarme-falso condicional. Esta tese adota esta abordagem condicional e analisa o efeito da estimação dos parâmetros do processo no desempenho conjunto dos gráficos de X e S em dois casos: Caso KU (Média conhecida – Variância desconhecida) e Caso UU (Média desconhecida – Variância desconhecida). A quase totalidade dos trabalhos anteriores considerou apenas um gráfico, isoladamente; sobre efeito da estimação dos parâmetros sobre o desempenho conjunto conhecemos apenas um trabalho, sobre gráficos de X e R, mas nenhum sobre gráficos de X e S. Os resultados da análise mostram que o desempenho dos gráficos pode ser muito afetado pela estimação de parâmetros e que o número de amostras iniciais requerido para garantir um desempenho desejado é muito maior que os números tradicionalmente recomendados na literatura normativa de controle estatístico de processo (livros texto e manuais). Esse número é, porém, menor que o máximo entre os números requeridos para os gráficos de X e de S individualmente. Questões a serem investigadas como desdobramento dessa pesquisa são também indicadas nas Considerações Finais e Recomendações. / [en] The false-alarm rate of control charts, alpha, depends on the control limits calculated, which depend, in turn, on the estimated process parameters. This dissertation initially presents a review of the main research articles about the effect of the estimation errors of the process parameters upon alpha when X and S charts are used separately and together. The charts performance is evaluated through performance measures (average run-length, false-alarm rate, run-length distribution, etc), which are, in general, random variables, function of the estimation errors. Recent researches focused on the properties of the conditional run-length, or still (in the case of Shewhart charts) on the properties of the conditional false-alarm rate distribution. This dissertation adopts this conditional approach and investigates the effect of parameter estimation on the joint behavior of X and S charts in two cases: KU Case (Known mean – Unknown variance) and UU Case (Unknown mean - Unknown variance). Almost all previous works considered just only one chart separately – just only one joint performance work is known by the author, one about the effect of the estimation errors of the process parameters upon X e R joint performance. The results show that the charts performance can be severely affected by the parameter estimation and the number of initial samples required to ensure the desirable performance is greater than the numbers of initial samples recommended by traditional statistical process control reference texts (books and manuals). This number is, however, smaller than the maximum between the numbers of samples required by the X and the S charts separately. Additional issues for follow-up research are recommended in the concluding section.
78

An Empirical Analysis of Herd Behavior in Sweden's First North Growth Market on NASDAQ Nordic

Singh, Bavneet, Maslarov, Boris January 2024 (has links)
In this paper, market participants’ tendency to form investor herds in the stocks listed on Nasdaq First North Growth Market of Sweden is examined for the period from 2018 to 2023. The models used in this study to detect herd behavior in stocks consist of two measures of dispersions, Cross-Sectional Standard Deviation of returns (CSSD) and Cross-Sectional Absolute Deviation of returns (CSAD), which were proposed by Christie and Huang (1995) and Chang, et al. (2000), respectively. An equally-weighted index consisting of all of the stocks that have traded on this market during the period is created and a quantitative analysis is conducted. Evidence showed absence of herd behavior when using both models, as well as when accounting for robustness tests consisting of small, mid-and large cap portfolios. Our results also support the prediction of rational asset pricing models, which suggest that stock return dispersions around the market returns increase during periods of market stress.
79

Minimization of Noise and Vibration Related to Driveline Imbalance using Robust Design Processes

Al-Shubailat, Omar 17 August 2013 (has links)
Variation in vehicle noise, vibration and harshness (NVH) response can be caused by variability in design (e.g. tolerance), material, manufacturing, or other sources of variation. Such variation in the vehicle response causes a higher percentage of produced vehicles to have higher levels (out of specifications) of NVH leading to higher number of warranty claims and loss of customer satisfaction, which are proven costly. Measures must be taken to ensure less warranty claims and higher levels of customer satisfactions. As a result, original equipment manufacturers (OEMs) have implemented design for variation in the design process to secure an acceptable (or within specification) response. The focus here will be on aspects of design variations that should be considered in the design process of drivelines. Variations due to imbalance in rotating components can be unavoidable or costly to control. Some of the major components in the vehicle that are known to have imbalance and traditionally cause NVH issues and concerns include the crankshaft, the drivetrain components (transmission, driveline, half shafts, etc.), and wheels. The purpose is to assess NVH as a result of driveline imbalance variations and develop a tool to help design a more robust system to such variations.
80

Development of high-performance algorithms for a new generation of versatile molecular descriptors. The Pentacle software

Durán Alcaide, Ángel 04 March 2010 (has links)
The work of this thesis was focused on the development of high-performance algorithms for a new generation of molecular descriptors, with many advantages with respect to its predecessors, suitable for diverse applications in the field of drug design, as well as its implementation in commercial grade scientific software (Pentacle). As a first step, we developed a new algorithm (AMANDA) for discretizing molecular interaction fields which allows extracting from them the most interesting regions in an efficient way. This algorithm was incorporated into a new generation of alignmentindependent molecular descriptors, named GRIND-2. The computing speed and efficiency of the new algorithm allow the application of these descriptors in virtual screening. In addition, we developed a new alignment-independent encoding algorithm (CLACC) producing quantitative structure-activity relationship models which have better predictive ability and are easier to interpret than those obtained with other methods. / El trabajo que se presenta en esta tesis se ha centrado en el desarrollo de algoritmos de altas prestaciones para la obtención de una nueva generación de descriptores moleculares, con numerosas ventajas con respecto a sus predecesores, adecuados para diversas aplicaciones en el área del diseño de fármacos, y en su implementación en un programa científico de calidad comercial (Pentacle). Inicialmente se desarrolló un nuevo algoritmo de discretización de campos de interacción molecular (AMANDA) que permite extraer eficientemente las regiones de máximo interés. Este algoritmo fue incorporado en una nueva generación de descriptores moleculares independientes del alineamiento, denominados GRIND-2. La rapidez y eficiencia del nuevo algoritmo permitieron aplicar estos descriptores en cribados virtuales. Por último, se puso a punto un nuevo algoritmo de codificación independiente de alineamiento (CLACC) que permite obtener modelos cuantitativos de relación estructura-actividad con mejor capacidad predictiva y mucho más fáciles de interpretar que los obtenidos con otros métodos.

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