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Showing 481 to 490 of 493 (0.029 seconds)Spelling suggestions: "subject:"[een] DEVIATION"" "subject:"[enn] DEVIATION""
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Kontroll av zinkskikt på monterat räckesmaterial / Check of zinc coating thickness on erected safety barriersFathi, 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.
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[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 CHARTSLORENA 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.
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Styrförändringar i offentlig sektor : En praktisk tillämpning av tillitsbaserad styrningGummesson, Malin, Slaveska, Martina January 2022 (has links)
Introduction: The abundance of reforms that have characterized governance in the public sectorin recent decades has shown a discrepancy between the reforms ambition and outcome, as the results of the reform implementation rarely reach expectations. In 2016, the government appointed a delegation with the aim of developing a new way of working that was based ontrust to deal with the problems that were perceived to exist in the public sector, the working method that was developed is called trust-based governance (TBS). As TBS is a relatively new and Swedish concept, there is a lack of empirical evidence on how various public authorities have introduced trust-based governance and developed their governance. Aim: The aim of this study is to increase knowledge about governance changes in the public sector and trust-based governance (TBS). To achieve this, the change work in a selected municipality that claims to work with TBS will be studied. Method: The study is a qualitative case study in a selected municipality, Östra Göinge. The empirical collection consists of two parts; first describes TBS based on Tilitsdelegationen definition and then TBS is examined in the selected municipality. The empirical collection from the municipality is mainly based on interviews with respondents on strategic, tactical and operationa levels but has been supplemented with documents from the municipality. Conclusion: Östra Göinge's change work has been developed with inspiration from the private sector and not based on the work of Tillitsdelegationen, but the municipality's current governance can be equated with the description of TBS that the delegation emphasizes. The municipality has influenced the delegation's work regarding the design of the trust reform, which shows that the design of public governance reforms can be influenced by the public sector. Furthermore, Östra Göinge's change work is described as an ongoing and dynamic process in which successive adjustments of control have been made in order to fix the gaps that exist between ambition and outcome. The outcome of the change work is judged to have been affected by; interpretation, intra-organizational factors, organizational characteristics, sedimentation, and contradictions, and of five challenges that exist with TBS as a way of governance; culture clashes, dismissals, difficulties in maintaining TBS and that there are no exact limits to the employee's playing field. / Inledning: Den uppsjö av reformer som har präglat styrningen av den offentliga sektorn under de senaste decennierna årtioenderna har påvisat en avvikelse mellan reformers ambition och utfall, då utfallet av reforminförandet sällan når upp till förväntningarna. 2016 tillsatte regeringen en delegation vars syfte var att utveckla ett nytt arbetssätt med tillit som utgångspunkt för att hantera de problem som upplevdes finnas inom den offentliga sektorn, detta nya arbetssätt kom att kallas tillitsbaserad styrning (TBS). Då TBS är ett svenskt och relativt nytt koncept saknas det empiriska underlag på hur olika offentliga myndigheter har anammat TBS och utvecklat sin styrning. Syfte: Syftet med denna studien är att öka kunskapen om styrförändringar i offentlig sektor och tillitsbaserad styrning (TBS). För att uppnå det här kommer ett förändringsarbete i en vald kommun som uppger sig arbeta med TBS studeras. Metod: Studien är en kvalitativ fallstudie av en vald kommun, Östra Göinge. Empiriinsamlingen består av två delar; den första beskriver TBS utifrån Tilitsdelegationens definition och sedan undersöks TBS i den valda kommunen. Empiriinsamlingen från kommunen bygger främst på intervjuer med respondenter på strategisk, taktisk och operativ nivå men har kompletterats med underlag från kommunen. Slutsats: Östra Göinges förändringsarbete har tagits fram med inspiration från den privata sektorn och inte utifrån Tillitsdelegationens arbete. Kommunens nuvarande styrning kan likställas med den beskrivning av TBS som delegationen framhåller. Kommunen har påverkat delegationens arbete kring utformningen av TBS och resultatet visar att utformningen av offentliga styrreformer kan påverkas av den privata sektorn. Vidare beskrivs Östra Göinges förändringsarbete som en pågående och dynamisk process där successiva justeringar har gjorts för att åtgärda gapen mellan ambition och utfall. Utfallet av förändringsarbetet bedöms ha orsakats av; tolkning, intraorganisatoriska faktorer, organisatoriska karaktärsdrag, sedimentation och motstridigheter. Det identifierades också fem utmaningar med TBS som styrsätt; kulturkrockar, uppsägningar, svårigheter att upprätthålla styrsättet samt att det inte finnsexakta gränser för spelplanen.
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Active versus passive portfolio management : A study of risk-adjusted return and market fluctuations on short term and long termDuveskog, Ida, Halldén, Jesper January 2024 (has links)
Today fund matching is a natural part of Swedes finance and is a popular form of savings that includes a large number of investors in the Swedish fund market. This in turn generates an increased interest in how portfolio managers should locate and acquire knowledge in portfolio selection. This gives a greater interest in how different investment strategies can be affected and generate an investors wealth to an increased level within the stock market, which gives an increased focus to be able to generate as high risk-adjusted return as possible. The study partly presents traditional theory and background on modern portfolio theory and the efficient market hypothesis. Empirical studies also present within the financial market that demonstrate the differences of opinion between how actively versus passively managed funds have performed and which investment strategy is most beneficial for investment. The purpose of the study is to compare realized return on active versus passive funds during long term, short term and specific time periods that had a lot of economic fluctuations, like bear markets. Within the study 10 actively managed funds and two index measures are selected to be studied and compared based on their respective performance, both within its rise and fall in the Swedish fund market. The performance measures will then be applied to be able to produce the results of the study and to be able to answer whether the active fund’s have any statistically significant over- and underperformance. After conducting single index models and t-test on the 10 active funds, the result of the study shows that despite using two benchmarks index, ten different active funds, long time period, short time period or specific time periods defined by market imbalance , we still resulted in many P-values that was not statistically significant. Active funds failed to overperform against passive funds, but passive funds also failed to outperform our selection of active funds.
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Application of the Duality TheoryLorenz, Nicole 15 August 2012 (has links) (PDF)
The aim of this thesis is to present new results concerning duality in scalar optimization. We show how the theory can be applied to optimization problems arising in the theory of risk measures, portfolio optimization and machine learning.
First we give some notations and preliminaries we need within the thesis. After that we recall how the well-known Lagrange dual problem can be derived by using the general perturbation theory and give some generalized interior point regularity conditions used in the literature. Using these facts we consider some special scalar optimization problems having a composed objective function and geometric (and cone) constraints. We derive their duals, give strong duality results and optimality condition using some regularity conditions. Thus we complete and/or extend some results in the literature especially by using the mentioned regularity conditions, which are weaker than the classical ones. We further consider a scalar optimization problem having single chance constraints and a convex objective function. We also derive its dual, give a strong duality result and further consider a special case of this problem. Thus we show how the conjugate duality theory can be used for stochastic programming problems and extend some results given in the literature.
In the third chapter of this thesis we consider convex risk and deviation measures. We present some more general measures than the ones given in the literature and derive formulas for their conjugate functions. Using these we calculate some dual representation formulas for the risk and deviation measures and correct some formulas in the literature. Finally we proof some subdifferential formulas for measures and risk functions by using the facts above.
The generalized deviation measures we introduced in the previous chapter can be used to formulate some portfolio optimization problems we consider in the fourth chapter. Their duals, strong duality results and optimality conditions are derived by using the general theory and the conjugate functions, respectively, given in the second and third chapter. Analogous calculations are done for a portfolio optimization problem having single chance constraints using the general theory given in the second chapter. Thus we give an application of the duality theory in the well-developed field of portfolio optimization.
We close this thesis by considering a general Support Vector Machines problem and derive its dual using the conjugate duality theory. We give a strong duality result and necessary as well as sufficient optimality conditions. By considering different cost functions we get problems for Support Vector Regression and Support Vector Classification. We extend the results given in the literature by dropping the assumption of invertibility of the kernel matrix. We use a cost function that generalizes the well-known Vapnik's ε-insensitive loss and consider the optimization problems that arise by using this. We show how the general theory can be applied for a real data set, especially we predict the concrete compressive strength by using a special Support Vector Regression problem.
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Hierarchie a chování člověka. BDSM jako alternativní sexuální chování. / Hierarchy and human behavior. BDSM as an alternative sexual behaviour.Jozífková, Eva January 2016 (has links)
Preferences for sexual arousal by overstated dominance and submission in sex is categorized as F65.5, sadomasochism, according to ICD, but this behaviour is called BDSM among the general public. The ground of these preferences could be ultimately biological. These preferences reflect behavioural strategy which enables to gain higher reproductive success. Men and women who were sexually aroused by a submissive partner had more male relatives than men and women with other preferences. Contrary to the women, the dominant men reported themselves as more attractive. Women who were aroused by a higher-ranking partner considered themselves more attractive. Sons of couples in which was hierarchical disparity had more siblings than sons of "equal" couples or couples with no hierarchical disparity. Daughters of hierarchically disparate couples had more brothers than daughters of "both dominant" partners. Concurrently, number and gender of offspring as well as self- reported attractiveness are likely to be criteria of the reproductive success in humans. It is also interesting that hierarchically disparate couples, without regard to gender of higher-ranking partner, reached higher reproductive success than "equal" couples. Individuals who preferred higher- or lower-ranking partner were also aroused by...
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Application of the Duality Theory: New Possibilities within the Theory of Risk Measures, Portfolio Optimization and Machine LearningLorenz, Nicole 28 June 2012 (has links)
The aim of this thesis is to present new results concerning duality in scalar optimization. We show how the theory can be applied to optimization problems arising in the theory of risk measures, portfolio optimization and machine learning.
First we give some notations and preliminaries we need within the thesis. After that we recall how the well-known Lagrange dual problem can be derived by using the general perturbation theory and give some generalized interior point regularity conditions used in the literature. Using these facts we consider some special scalar optimization problems having a composed objective function and geometric (and cone) constraints. We derive their duals, give strong duality results and optimality condition using some regularity conditions. Thus we complete and/or extend some results in the literature especially by using the mentioned regularity conditions, which are weaker than the classical ones. We further consider a scalar optimization problem having single chance constraints and a convex objective function. We also derive its dual, give a strong duality result and further consider a special case of this problem. Thus we show how the conjugate duality theory can be used for stochastic programming problems and extend some results given in the literature.
In the third chapter of this thesis we consider convex risk and deviation measures. We present some more general measures than the ones given in the literature and derive formulas for their conjugate functions. Using these we calculate some dual representation formulas for the risk and deviation measures and correct some formulas in the literature. Finally we proof some subdifferential formulas for measures and risk functions by using the facts above.
The generalized deviation measures we introduced in the previous chapter can be used to formulate some portfolio optimization problems we consider in the fourth chapter. Their duals, strong duality results and optimality conditions are derived by using the general theory and the conjugate functions, respectively, given in the second and third chapter. Analogous calculations are done for a portfolio optimization problem having single chance constraints using the general theory given in the second chapter. Thus we give an application of the duality theory in the well-developed field of portfolio optimization.
We close this thesis by considering a general Support Vector Machines problem and derive its dual using the conjugate duality theory. We give a strong duality result and necessary as well as sufficient optimality conditions. By considering different cost functions we get problems for Support Vector Regression and Support Vector Classification. We extend the results given in the literature by dropping the assumption of invertibility of the kernel matrix. We use a cost function that generalizes the well-known Vapnik's ε-insensitive loss and consider the optimization problems that arise by using this. We show how the general theory can be applied for a real data set, especially we predict the concrete compressive strength by using a special Support Vector Regression problem.
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Hierarchie a chování člověka. BDSM jako alternativní sexuální chování. / Hierarchy and human behavior. BDSM as an alternative sexual behaviour.Jozífková, Eva January 2016 (has links)
Preferences for sexual arousal by overstated dominance and submission in sex is categorized as F65.5, sadomasochism, according to ICD, but this behaviour is called BDSM among the general public. The ground of these preferences could be ultimately biological. These preferences reflect behavioural strategy which enables to gain higher reproductive success. Men and women who were sexually aroused by a submissive partner had more male relatives than men and women with other preferences. Contrary to the women, the dominant men reported themselves as more attractive. Women who were aroused by a higher-ranking partner considered themselves more attractive. Sons of couples in which was hierarchical disparity had more siblings than sons of "equal" couples or couples with no hierarchical disparity. Daughters of hierarchically disparate couples had more brothers than daughters of "both dominant" partners. Concurrently, number and gender of offspring as well as self- reported attractiveness are likely to be criteria of the reproductive success in humans. It is also interesting that hierarchically disparate couples, without regard to gender of higher-ranking partner, reached higher reproductive success than "equal" couples. Individuals who preferred higher- or lower-ranking partner were also aroused by...
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Minimization of Noise and Vibration Related to Driveline Imbalance using Robust Design ProcessesAl-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.
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Development of high-performance algorithms for a new generation of versatile molecular descriptors. The Pentacle softwareDurán 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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