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Enhanced sampling and applications in protein foldingZhang, Cheng 24 July 2013 (has links)
We show that a single-copy tempering method is useful in protein-folding simulations of large scale and high accuracy (explicit solvent, atomic representation, and physics-based potential). The method uses a runtime estimate of the average potential energy from an integral identity to guide a random walk in the continuous temperature space. It was used for folding three mini-proteins, trpzip2 (PDB ID: 1LE1), trp-cage (1L2Y), and villin headpiece (1VII) within atomic accuracy.
Further, using a modification of the method with a dihedral bias potential added on the roof temperature, we were able to fold four larger helical proteins: α3D (2A3D), α3W (1LQ7), Fap1-NRα (2KUB) and S-836 (2JUA).
We also discuss how to optimally use simulation data through an integral identity. With the help of a general mean force formula, the identity makes better use of data collected in a molecular dynamics simulation and is more accurate and precise than the common histogram approach.
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Modelling a Manufacturing line : Analysis and Decision support based on Discrete Event SimulationIbrahim, Fady January 2011 (has links)
The increasing competition between the companies forces them to develop the production in a continuous manner in order to maintain the competitiveness in the global market, and became as efficient and effective as possible. This master thesis is conducted at Getrag All Wheel Drive Company which is one of the largest suppliers for transmissions and powertrain systems .This Company has worked actively for long time to improve the production flow at the manufacturing departments by using usual methods. Because of the high complex and intersected flow that the company has, the management intended to adopt another approach that takes dynamic information into consideration, therefore, building a simulation model is the solution, where according to Banks et al (2001) the simulation is a duplication of a real-world process or system and its behaviour as it progress during the time, which is a very useful method to evaluate complex systems, instead of using usual mathematical means used tools. The simulation model created by using Banks et al (2001) simulation methodology, and ExtendSim software help. The resulted model used as a tool that provides great assistance to the decision makers, in order to develop the Conwip system which applied in the manufacturing line under study, and to investigate “What if” scenarios. The result of this study obtained after performing two experiments, where the first experiment gives recommendation regarding the optimal upper bound of the total amount of work that can be used in Conwip system, with the use of sensitivity analysis, and the second experiment analyse the overall all effect on the system after separating the paths of high and low volume products. This project proves the powerful side of using the simulation in situations where it’s too hard or even impossible to improve the performance of a manufacturing line i.e. when large number of variables involved and affecting the system.
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Artificial Transactional Data Generation for Benchmarking Algorithms / Generering av artificiell transaktionsdata för att prestandamäta algoritmerLundgren, Veronica January 2023 (has links)
Modern retailers have been collecting more and more data over the past decades. The increased sizes of collected data have led to higher demand for data analytics expertise tools, which the Umeå-founded company Infobaleen provides. A recurring challenge when developing such tools is the data itself. Difficulties in finding relevant open data sets have led to a rise in the popularity of using synthetic data. By using artificially generated data, developers gain more control over the input when testing and presenting their work. However, most methods that exist today either depend on real-world data as input or produce results that look synthetic and are difficult to extend. In this thesis, I introduce a method specifically designed to generate synthetic transactional data stochastically. I first examined real-world data provided by Infobaleen to determine suitable statistical distributions to use in my algorithm empirically. I then modelled individual decision-making using points in an embedding space, where the distance between the points serves as a basis for individually unique probability weights. This solution creates data distributed similarly to real-world data and enables retroactive data enrichment using the same embeddings. The result is a data set that looks genuine to the human eye but is entirely synthetic. Infobaleen already generates data with this model when presenting its product to new potential customers or partners.
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SAFETY STOCK PLANNING AND SUPPLY CHAIN OPTIMIZATION IN STOCK STATUSLi, Ruoxi January 2019 (has links)
This paper proposes a safety stock calculation function based on their distribution properties and create a guideline for the stock status optimization problem. The motivation for this paper originates the cooperation with a drilling tools company, Epiroc Drilling tools AB. The safety stock calculation divides all items into three distribution and design the safety stock for each types separately considering the influence of service level value and lead time. During the process of guideline design, complicated production chain framework is taken into account through recursive algorithm. The stock status combination which can give the minimum storage cost is the optimal guideline for stock item and non-stock item. The time for approximating the global minimum through exhaustive search is remarkably reduced due to the application of Parallel programming and statistical model.
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Model pro ekonomickou simulaci procesů (sledování nákladů na nízkou jakost) / Model for Economical Process Simulation (Cost of Poor Quality Monitoring)Janíková, Dita January 2011 (has links)
This work is dealing with a study of process simulation and its use for the costs of poor quality monitoring. The process simulation is generally in many companies not too used and moreover, there is no software at the market, which would easily described economical efficiency of processes. The main purpose of this work is to suggest such a application. The study contains of the detailed data models for each function of the application, requirements specification and the feasibility study, which provide approximate costs for the development of such a application.
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Abordagem microbiológica e estatística aplicada ao monitoramento ambiental em áreas produtivas farmacêuticas / Microbiological and statistical approach applied to environmental monitoring of pharmaceutical manufacturing areasLirio, Adriana Cogo Malgueiro 08 February 2019 (has links)
O controle microbiológico durante a produção de preparações farmacêuticas é de grande importância para garantir a qualidade do produto final, quanto às propriedades terapêuticas e de segurança ao paciente. O monitoramento ambiental é uma valiosa ferramenta como forma de mensurar a efetividade das medidas que integram a estratégia de controle de contaminação microbiana. Neste contexto, pouco destaque tem sido dado à manufatura de produtos farmacêuticos não-estéreis, por representarem as classes cujos riscos de contaminação microbiana são menores, quando comparados aos produtos parenterais. Dessa maneira, este estudo teve como objetivo caracterizar os isolados microbianos de amostras de ar ativo e passivo e de superfícies de áreas produtivas não-estéreis. Ainda, visou-se avaliar estatisticamente os dados de monitoramento ambiental, como base para o desenvolvimento de uma abordagem para determinação de limites de alerta e ação. Os resultados obtidos revelaram que a maioria dos microrganismos encontrados são de origem humana, seguidos por bactérias e fungos provenientes do solo. As diferenças sazonais foram observadas, principalmente, para a ocorrência de fungos, mais prevalentes no período seco. Foi desenvolvida uma abordagem estatística baseada em (1) determinação de subgrupos racionais, (2) avaliação da distribuição estatística e (3) determinação de limites, utilizando, como critério, o índice de capacidade do processo (Cpk). Um melhor entendimento do perfil microbiano das áreas produtivas e a determinação de limites de acordo com a distribuição real dos dados levará à destinação dos recursos necessários a ações que visem a qualidade do produto e a segurança do paciente. / The microbiological control during the production of pharmaceutical preparations is of great importance for quality assurance of the final product regarding to therapeutic properties and patient safety. Environmental monitoring is a valuable tool to measure the effectiveness of the actions that integrate the microbial contamination control strategy. In this context, little attention has been given to the manufacture of non-sterile pharmaceutical products, because they represent classes whose microbial contamination risks are lower when compared to parenteral products. Considering this scenario, this study aimed to characterize microbial isolates from surfaces, active and passive air sampling of non-sterile manufacturing areas. Furthermore, it was expected to statistically evaluate the environmental monitoring data, as a basis for the development of an approach for determining alert and action limits. The results showed that most of the microorganisms found are from human source, followed by bacteria and fungi typically found in the soil. The seasonal differences were mainly observed for fungi recovery, which were more prevalent in the dry period. A statistical approach was developed based on (1) the determination of rational subgroups, (2) evaluation of the statistical distribution and (3) limit determination, using the process capacity index (Cpk) as criteria. A better understanding of the typical manufacturing areas microbial profile and the determination of limits according to the actual data distribution will lead to the allocation of the necessary resources to actions focusing on product quality and patient safety.
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Variabilité des performances de bétons de chanvre en fonction des caractéristiques de la chènevotte produite en Auvergne / Performance variability of hemp concretes according to the characteristics of the hemp particles produced in AuvergneNiyigena, César 03 June 2016 (has links)
Les origines de la variabilité des propriétés du matériau béton de chanvre sont nombreuses. On distingue celles liées aux propriétés des ses constituants et du matériau lui-même auxquelles il faut ajouter les dispersions qui résultent des méthodes utilisées pour caractériser ce béton. Ce travail de thèse, s’intéresse à l’étude de la variabilité des propriétés du béton de chanvre en tenant compte de ces différentes sources et en particulier au type de chènevotte utilisée. L’étude bibliographique réalisée permet de comprendre le matériau béton de chanvre, notamment ses constituants, les méthodes de caractérisations en usage ainsi que l’ampleur de la variabilité et de la sensibilité de ses propriétés vis-à-vis des différents paramètres. Cet état de l’art, permet en outre d’identifier les paramètres à considérer dans le cadre de cette thèse. Notre travail de thèse est alors subdivisé en 4 chapitres en plus de l’étude bibliographique. Dans le deuxième chapitre, une étude multicritère sur les propriétés des chènevottes est présentée. Après une campagne expérimentale de caractérisation de 13 types de chanvre, une analyse des résultats à deux niveaux est réalisée. Elle prend en compte, la masse volumique, la capacité d’absorption d’eau et la granulométrie. Dans un premier temps on présente les résultats de l’étude mono-caractéristique ; il s’agit de la comparaison d’une caractéristique donnée pour l’ensemble des chènevottes. Dans un second temps, on présente les résultats de l’étude multicritère. Il s’agit d’analyser l’ensemble des chènevottes en prenant en comptes les différentes caractéristiques à la fois. A l’issue, les chènevottes sont classées en trois groupes. Le chapitre 3 constitue une étude préliminaire tenant compte des différents paramètres sources de variabilités des propriétés du béton de chanvre, comme le laboratoire d’essai (équipements), la gâchée, la taille d’éprouvette et le type de chanvre. Les résultats obtenus montrent la nécessité d’étudier l’impact du type de la chènevotte. Par ailleurs, la dispersion considérable obtenue pour les résultats du module d’Young est vraisemblablement associée à sa méthode de calcul. Il devient alors important d’approfondir l’étude de son impact sur les valeurs du module d’Young obtenues. Le chapitre 4 vise justement à étudier les méthodes de calcul du module d’Young. Les différentes méthodes de la littérature sont alors utilisées pour exploiter les courbes contrainte-déformation dont les essais ont été réalisés dans les mêmes conditions. Les variabilités observées sur les résultats vis-à-vis de chacune des méthodes permettent alors de mettre en évidence leur impact et de proposer la méthode « flottante » comme étant la plus pertinente. Par ailleurs, un modèle permettant de décrire la loi de comportement mécanique du béton de chanvre est proposé. Il permet de déterminer la courbe enveloppe correspondant à la courbe expérimentale issue du chargement monotone, et permet également de reproduire la courbe expérimentale issue d’un chargement cyclique. Dans le dernier chapitre, en se basant sur les résultats du chapitre 2, neuf types de chanvre ont été sélectionnés pour la confection des éprouvettes de l’étude. Dans les mêmes conditions (fabrication et essai), il a été mis en évidence expérimentalement l’impact de la chènevotte sur les propriétés mécaniques avec un facteur égal à 10 entre les valeurs faibles et élevées. La réponse mécanique caractérisée par des faibles (<5%), moyennes (>5% et <8%) et fortes (>8% et <20%) niveau de déformation a été mis en évidence. Ces variabilités, restent cependant moins marquées pour la conductivité thermique et la masse volumique du béton de chanvre. L’étude met en évidence l’intérêt d’une étude approfondie sur l’interaction liant/chènevotte pour une meilleure compréhension de l’impact de la chènevotte sur le béton de chanvre. / The origins of the variability of hemp concrete material properties are numerous. They include among others those related to the properties of its constituents and material itself as well as the methods used for their characterizations. This thesis is interested in the study of the variability of hemp concrete properties taking into account these different parameters and in particular the type of hemp particles used. The litterature review corried out allowed to present the hemp concrete material, the properties of its constituents, their methods of characterization and also the extend of properties variability and sensitivity due to various parameters. Furthermore, it allowed to identify the parameters to be considered in the context of this thesis. Therefore, this thesis is devided into four chapters in addition to the literature review. In the second chapter, a multi-criteria study on the properties of hemp particles is presented. After an experimental study of characterization for 13 types of hemp particles, a two level analysis of result is performed. It takes into account the density, water absorption capacity and particle size distributions. First, the results of the single characteristic study are presented; it is about a comparison of a given characterstic for all hemp particles at the same time. Secondly, the results of the multi-criteria study are presented. In this last case, the analysis is corried out by taking into account all hemp particles and characteristics, both at the same time. The outcome of this study allowed to classify hemp particles into three groups from which, low, medium and high mechanical peformances are expected, respectively. Chapter 3 is a preliminary study taking into account various parameters as sources of variability for hemp concrete properties, such as the testing laboratory (equipments), the batch, the specimen size and hemp particles type. The obtained results highlight the need for further investigations about the impact of hemp particles type. Moreover, the considerable dispersion in the results of Young’s modulus is likely associated with its calculation method. It then becomes important to deepen the study of its impact on the values of Young’s modulus obtained. The chapter 4 aims to answer the problem found on the method for calculating the Young’s modulus. Various methods from literature are used to analyse the stress-strain curves from samples manufactured under the same conditions. The variability observed in results with respect to used method allowed to highlight their impact and to provide the floating method as the most pertinent since it presents less variability. In addition, a model to describe the mechanical behavior law of hemp concrete is proposed. It allows to determine the enveloppe curve which corresponds to experimental curve from the monotonic loading. It can also allow to reproduce the experimental curve from a cyclic loading. In the last chapter, based on the results of chapter 2, nine types of hemp particles were selected for the preparation and manufacturing of specimens of the study. Under the same conditions (manufacturing and test), it has been demonstrated experimentally the impact of hemp particles on mechanical properties with a factor 10 between low and high values from obtained results. The mechanical response characterized by low (<5%), medium (>5% and <8%) and high (> 8% and <20%) level of deformation have been highlighted. These variabilities remain, however less marked for thermal conductivity and density of hemp concrete material. This study highlights the interest of a comprehensive study on the interaction binder/hemp particles for a better understanding of the impact of hemp particles on hemp concrete.
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[en] MEASUREMENTS AND MODELS FOR THE PROPAGATION LOSS AND RECEPTION QUALITY IN MOBILE BROADCAST SYSTEMS / [pt] MEDIÇÕES E MODELAGEM DA PERDA DE PROPAGAÇÃO E QUALIDADE DE RECEPÇÃO EM SISTEMAS DE RADIODIFUSÃO COM MOBILIDADECLARA ELIZABETH VERDUGO MUNOZ 09 August 2017 (has links)
[pt] O Ministério da Comunicações vem incentivando a realização de avaliações com sistemas de radiodifusão sonora digital, visando a futura decisão para a escolha do Padrão de Rádio Digital a ser adotado no País. Nos anos de 2012 a 2014 foram realizadas pelo CETUC, em parceria com o Ministério da Comunicações, a Anatel e o Inmetro, campanhas de medições nas faixas de ondas médias e VHF em algumas cidades do país, para avaliar os padrões de radiodifusão digital e subsidiar a decisão em curso sobre o padrão a ser adotado no Brasil. As campanhas envolveram medições estáticas e medições com mobilidade. Os dados das medições estáticas já foram analisados e os resultados divulgados. Neste trabalho são analisados os resultados das medições móveis. A primeira parte desse estudo trata da comparação dos resultados experimentais com os modelos de predição semiempíricos. Posteriormente, a análise estatística da variabilidade do sinal recebido em termos dos desvanecimentos de larga e pequena escala. Na parte final, a qualidade de recepção e a cobertura do sinal digital foram analisados a partir dos dados das medições. / [en] The Communications Ministry has been encouraging evaluations with digital sound broadcasting systems, aiming at the future decision for the Digital Radio Standard choice to be adopted in Brazil. In 2012 to 2014 were carried out by CETUC, in partnership with the Communications Ministry, Anatel and Inmetro,
measurements campaigns at the medium and VHF bands in some cities of the country, to evaluate the digital broadcasting standards and to subsidize the current decision on the standard to be adopted in Brazil. Static and mobility measurements were involved at the campaign. The static measurement data have already been analyzed and the results reported. In this work, the mobile measurements results are analyzed. At the first part of this study deals with the comparison between experimental results with prediction models. Subsequently, statistical analysis of the received signal variability in terms of large and small scale fading were done. In the final part, reception quality and digital signal coverage were examined from the measurement data.
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Static Partial Order Reduction for Probabilistic Concurrent SystemsFernández-Díaz, Álvaro, Baier, Christel, Benac-Earle, Clara, Fredlund, Lars-Åke 10 September 2013 (has links) (PDF)
Sound criteria for partial order reduction for probabilistic concurrent systems have been presented in the literature. Their realization relies on a depth-first search-based approach for generating the reduced model. The drawback of this dynamic approach is that it can hardly be combined with other techniques to tackle the state explosion problem, e.g., symbolic probabilistic model checking with multi-terminal variants of binary decision diagrams. Following the approach presented by Kurshan et al. for non-probabilistic systems, we study partial order reduction techniques for probabilistic concurrent systems that can be realized by a static analysis. The idea is to inject the reduction criteria into the control flow graphs of the processes of the system to be analyzed. We provide the theoretical foundations of static partial order reduction for probabilistic concurrent systems and present algorithms to realize them. Finally, we report on some experimental results.
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Fundamenta??o cin?tica da estat?stica n?o gaussiana : efeitos em politr?picasBento, Eli?ngela Paulino 19 September 2011 (has links)
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Previous issue date: 2011-09-19 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Considering a non-relativistic ideal gas, the standard foundations of
kinetic theory are investigated in the context of non-gaussian statistical mechanics
introduced by Kaniadakis. The new formalism is based on the generalization
of the Boltzmann H-theorem and the deduction of Maxwells
statistical distribution. The calculated power law distribution is parameterized
through a parameter measuring the degree of non-gaussianity. In
the limit = 0, the theory of gaussian Maxwell-Boltzmann distribution is
recovered. Two physical applications of the non-gaussian effects have been
considered. The first one, the -Doppler broadening of spectral lines from
an excited gas is obtained from analytical expressions. The second one,
a mathematical relationship between the entropic index and the stellar
polytropic index is shown by using the thermodynamic formulation for
self-gravitational systems / Considerando um g?s ideal n?o relativ?stico, os fundamentos da teoria
cin?tica padr?o s?o investigados no contexto da mec?nica estat?stica
n?o-gaussiana introduzida por Kaniadakis. O novo formalismo ? baseado
na generaliza??o do teorema-H de Boltzmann e na dedu??o de Maxwell
da distribui??o estat?stica. A distribui??o lei de pot?ncia calculada ?
parametrizada por um par?metro medindo o grau de n?o-gaussianidade
do sistema. No limite = 0, a teoria gaussiana de Maxwell-Boltzmann
? recuperada. Duas aplica??es dos efeitos n?o-gaussiano s?o estudados.
Na primeira, o -alargamento Doppler das linhas espectrais de um g?s excitado
? obtido a partir das express?es anal?ticas. Na segunda, uma rela??o
matem?tica entre o ?ndice entr?pico e o ?ndice politr?pico estelar
? mostrada usando uma formula??o termodin?mica para sistemas autogravitantes
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