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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.
11

Modelos multi-escala localmente perturbativos para o transporte de solutos iônicos em meios porosos argilosos / Locally perturbative multiscale methods for ionic solute transport in clayly soils

Igreja, Iury Higor Aguiar da 05 August 2010 (has links)
Made available in DSpace on 2015-03-04T18:51:21Z (GMT). No. of bitstreams: 1 Iury.pdf: 2129454 bytes, checksum: 6a7aff5ca085814119b9518b0aab9bef (MD5) Previous issue date: 2010-08-05 / Conselho Nacional de Desenvolvimento Cientifico e Tecnologico / This work aims at developing computational models capable of furnishing more realistic and less costly computationally for the problem of electrokinetic remediation of polluted clayey soils. Innovative results are obtained by improving the multiscale models previously developed by Lima and co-workers through the construction of perturbations of the local microscopic problems in conjuction with more realistic boundary conditions at the electrodes and with the development of precise estimates for the assymptotic behavior of the macroscopic solution. Considering the aliance of such techniques within the framework of the homogenization method of periodic structures we discretize the macroscopic model by the finite element method numerical simulations of an electroosmose experiment capable of predicting more realistic scenarios of electrokinetic remediation. / Este trabalho objetiva o desenvolvimento de modelos computacionais capazes de construir simulações numéricas mais realistas e menos custosas computacionalmente para o problema de descontaminação de solos argilosos por técnicas de eletrocinética. Resultados inovadores são obtidos aprimorando-se os modelos multi-escala desenvolvidos anteriormente por Lima e colaboradores via construção de soluções perturbativas dos problemas locais microscópicos aliada à condições de contorno mais realistas nos eletrodos e ao desenvolvimento de estimativas precisas para o comportamento assintótico da solução macroscópica. Por intermédio da conjunção destas técnicas imersas no contexto da teoria de homogeneização de estruturas periódicas discretizamos o modelo macroscópico pelo método dos elementos finitos e construimos simulações numéricas de um experimento de eletroosmose capazes de predizer cenários mais realistas em eletrorremediação de solos.
12

Análise do comportamento de microestruturas heterogêneas pelo método dos elementos de contorno considerando-se não-linearidade física /

Crozariol, Luis Henrique de Rezende January 2017 (has links)
Orientador: Gabriela Rezende Fernandes / Resumo: Neste trabalho é apresentada uma formulação do MEC (Método dos Elementos de Contorno) considerando-se não-linearidade física para analisar microestruturas de materiais heterogêneos no contexto da análise em multi-escala. A microestrutura, também denominada como EVR (Elemento de Volume Representativo), é modelada como uma chapa em sub-regiões onde vazios ou inclusões podem ser considerados dentro da matriz, sendo diferentes propriedades elásticas e modelos constitutivos definidos para cada sub-região. A equação integral para o deslocamento é obtida a partir do Teorema de Betti, onde para considerar o fenômeno dissipativo, um campo de esforços iniciais é considerado. A equação algébrica da chapa é obtida após a discretização do contorno externo e interface em elementos e do domínio das subregiões em células. Na análise multi-escala cada ponto da estrutura (macrocontínuo) é representado por um EVR, onde o comportamento do material não é definido por um modelo constitutivo, mas através da solução do problema de equilíbrio do EVR quando sujeito à deformação referente ao ponto do macrocontínuo. O problema de equilíbrio do EVR é definido em termos da flutuação dos deslocamentos, sendo o mesmo satisfeito quando seu campo de forças se encontra em equilíbrio. Após a solução do EVR, os deslocamentos no contorno e as forças dissipativas são atualizados e as forças de superfície sobre o contorno recalculadas para se obter a tensão homogeneizada. O custo computacional obtido com a presente... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre
13

Um modelo de duas escalas da resposta elétrica de tecido muscular induzida por ativação de mastócitos / 2-Scales modelling electrical response from muscular tissue induced by mast cells activation.

Esbel Tomás Valero Orellana 28 February 2010 (has links)
O estudo dos mecanismos que desencadeiam as reações alérgicas é um tema de grande interesse científico na atualidade. A anafilaxia, reação alérgica sistêmica severa, tem ocupado um lugar de destaque nas pesquisas. Diferentes experimentos em laboratório, tanto in vivo quanto in vitro, assim como diferentes modelos matemáticos baseados nos resultados experimentais, têm procurado investigar a participação ou não dos mastócitos nesse mecanismo. No entanto, os resultados obtidos não são conclusivos, dividindo a comunidade científica em dois grupos: os que consideram determinante o papel dos mastócitos responsáveis pela liberação de histamina e os que consideram que a histamina não é o neurotransmissor determinante na reação anafilática. Trabalhos anteriores propuseram modelos diferenciais para simular processos relacionados com a reação anafilática na escala celular para o mecanismo de geração de potencial na membrana das células. Mais recentemente foi proposto, a nível de tecido, um modelo probabilístico para simular a resposta in vitro a antígenos. A nível de organismo têm sido propostos modelos de multi compartimentos para a cinética da histamina no fluido sanguíneo. Contudo, nenhum trabalho até o momento abordou a construção de um modelo capaz de descrever os processos que participam no mecanismo de reação anafilática nas diversas escalas. Neste trabalho propomos um modelo que integra as escalas celular e do tecido, que permite modelar experimentos in vitro, e que pode ser estendido para escala do organismo incluindo o fluxo sanguíneo para modelar experimentos in vivo. O modelo proposto integra o mecanismo de resposta elétrica a nível celular com o processo de reação-difusão da histamina e dos antígenos no tecido, considerando o mecanismo de reação mediado por mastócitos. Para integrar as duas escalas propomos uma relação constitutiva baseada em resultados experimentais da resposta mecânica (contração do tecido) a estímulos elétricos. Este modelo permite o desenho de novos experimentos especificamente direcionados ao estudo da reação anafilática, indicando os parâmetros a serem estimados. Utilizando-se o modelo proposto, foram realizadas simulações numéricas para uma ampla faixa de variação dos parâmetros visando identificar domínios com diferentes comportamentos do modelo. Uma análise dos resultados obtidos baseada em parâmetros adimensionais é apresentada. / The study of the mechanisms that set off allergic reactions is being a subject of great scientific interest. Anaphylaxis, severe systemic allergic reaction, occupies a prominence place in researches. Different laboratory experiments, in vivo as well as in vitro, and also different mathematical models based on experimental results, tries to investigate if mast cells takes part in those mechanisms or not. However, the obtained results are inconclusive, dividing the scientific community in two groups: one considering that mast cells have a prime role in releasing histamine, and another one which considers that histamine is not the determinative neurotransmitter in the anaphylactic reaction. Previous works proposed differential models to simulate processes related to anaphylactic reactions in the cellular scale for the cell membrane potential generation mechanism. More recently, it has been proposed a probabilistic model, in the tissue scale, to simulate an in vitro antigen response. In the organism level scale, multi-compartimental models have been proposed for the kinetics of histamine in the blood. Nevertheless, no work, until now, has proposed the construction of a model that is able to describe the processes that participate in the mechanism of anaphylactic reaction in different scales. In this work, a model is proposed that integrates the cellular and the tissue scales, allowing to model in vitro experiments, being capable to be extended to the organism scale by the inclusion of the blood flow to model in vivo experiments. The proposed model couples the electric response in the cellular level with the reaction-diffusion of histamine and antigens in the tissue, considering the reaction mechanism mediated by the mast cells. To integrate these two scales, it is proposed here a constitutive relation based on experimental results for the mechanical response (tissue contraction) to electric stimulus. This model allows to design experiments specifically related to the anaphylaxis reaction, indicating the parameters that should be estimated. With this model, numerical simulations have been performed for a wide variation range of the parameters to identify the different domains of the model. A dimensionless parameter based analysis is presented for the obtained results.
14

Locally perturbative multiscale methods for ionic solute transport in clayly soils / Modelos multi-escala localmente perturbativos para o transporte de solutos iônicos em meios porosos argilosos

Iury Higor Aguiar da Igreja 05 August 2010 (has links)
This work aims at developing computational models capable of furnishing more realistic and less costly computationally for the problem of electrokinetic remediation of polluted clayey soils. Innovative results are obtained by improving the multiscale models previously developed by Lima and co-workers through the construction of perturbations of the local microscopic problems in conjuction with more realistic boundary conditions at the electrodes and with the development of precise estimates for the assymptotic behavior of the macroscopic solution. Considering the aliance of such techniques within the framework of the homogenization method of periodic structures we discretize the macroscopic model by the finite element method numerical simulations of an electroosmose experiment capable of predicting more realistic scenarios of electrokinetic remediation. / Este trabalho objetiva o desenvolvimento de modelos computacionais capazes de construir simulações numéricas mais realistas e menos custosas computacionalmente para o problema de descontaminação de solos argilosos por técnicas de eletrocinética. Resultados inovadores são obtidos aprimorando-se os modelos multi-escala desenvolvidos anteriormente por Lima e colaboradores via construção de soluções perturbativas dos problemas locais microscópicos aliada à condições de contorno mais realistas nos eletrodos e ao desenvolvimento de estimativas precisas para o comportamento assintótico da solução macroscópica. Por intermédio da conjunção destas técnicas imersas no contexto da teoria de homogeneização de estruturas periódicas discretizamos o modelo macroscópico pelo método dos elementos finitos e construimos simulações numéricas de um experimento de eletroosmose capazes de predizer cenários mais realistas em eletrorremediação de solos.
15

Análise do comportamento de microestruturas heterogêneas pelo método dos elementos de contorno considerando-se não-linearidade física / Analysis of the behavior of heterogeneous microstructures by the boundary element method considering physical nonlinearity

Crozariol, Luis Henrique de Rezende [UNESP] 31 July 2017 (has links)
Submitted by LUIS HENRIQUE DE REZENDE CROZARIOL null (luiscrozariol@gmail.com) on 2017-09-26T22:06:47Z No. of bitstreams: 1 Dissertação Luis 26-09.pdf: 3642072 bytes, checksum: 6bd5d174cfe596f9dc2def41f1270185 (MD5) / Approved for entry into archive by Monique Sasaki (sayumi_sasaki@hotmail.com) on 2017-09-28T13:33:18Z (GMT) No. of bitstreams: 1 crozariol_lhr_me_ilha.pdf: 3642072 bytes, checksum: 6bd5d174cfe596f9dc2def41f1270185 (MD5) / Made available in DSpace on 2017-09-28T13:33:18Z (GMT). No. of bitstreams: 1 crozariol_lhr_me_ilha.pdf: 3642072 bytes, checksum: 6bd5d174cfe596f9dc2def41f1270185 (MD5) Previous issue date: 2017-07-31 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Neste trabalho é apresentada uma formulação do MEC (Método dos Elementos de Contorno) considerando-se não-linearidade física para analisar microestruturas de materiais heterogêneos no contexto da análise em multi-escala. A microestrutura, também denominada como EVR (Elemento de Volume Representativo), é modelada como uma chapa em sub-regiões onde vazios ou inclusões podem ser considerados dentro da matriz, sendo diferentes propriedades elásticas e modelos constitutivos definidos para cada sub-região. A equação integral para o deslocamento é obtida a partir do Teorema de Betti, onde para considerar o fenômeno dissipativo, um campo de esforços iniciais é considerado. A equação algébrica da chapa é obtida após a discretização do contorno externo e interface em elementos e do domínio das subregiões em células. Na análise multi-escala cada ponto da estrutura (macrocontínuo) é representado por um EVR, onde o comportamento do material não é definido por um modelo constitutivo, mas através da solução do problema de equilíbrio do EVR quando sujeito à deformação referente ao ponto do macrocontínuo. O problema de equilíbrio do EVR é definido em termos da flutuação dos deslocamentos, sendo o mesmo satisfeito quando seu campo de forças se encontra em equilíbrio. Após a solução do EVR, os deslocamentos no contorno e as forças dissipativas são atualizados e as forças de superfície sobre o contorno recalculadas para se obter a tensão homogeneizada. O custo computacional obtido com a presente formulação é menor que aquele referente ao modelo desenvolvido pelo Método dos Elementos Finitos, sendo a resposta homogeneizada do EVR comparada ao modelo de elementos finitos a fim de validar a formulação apresentada nesse trabalho. / A BEM formulation, considering dissipative phenomena, to analyze microstructures of heterogeneous materials in the context of multi-scale analysis is presented. The microstructure, also denoted as RVE (Representative Volume Element), is modelled as a zoned plate where voids or inclusions can be considered inside a matrix, being different elastic properties and constitutive models defined for each sub-region. The integral representation for displacement is obtained from Betti’s Theorem, where to consider the dissipative phenomena, an initial forces field is considered. The plate algebraic equation is obtained after discretizing the external boundary and interfaces into elements and the sub-regions domain into cells. In the multi-scale analysis, each macro-continuum point is represented by a RVE, being the material behaviour not governed by a phenomenological constitutive model, but defined after the solution of the RVE equilibrium problem due to the macro strain. The RVE equilibrium problem is defined in terms of displacement fluctuations, being satisfied when the forces field is in equilibrium. After the RVE solution, the boundary displacements and dissipative forces are updated and the boundary tractions recalculated to obtain the homogenized stress. The computational cost obtained with the proposed formulation is smaller than the formulation developed by the Finite Element Method. Besides, the homogenized response is compared to the finite element model to show its accuracy.
16

Sistemas orbitais e a?reos aplicados ? an?lise multi-escala da tect?nica r?ptil atuante na borda sudeste da Bacia do Parna?ba

Justo, Ana Paula 25 August 2006 (has links)
Made available in DSpace on 2015-03-13T17:08:39Z (GMT). No. of bitstreams: 1 AnaPJ_ate_cap4.pdf: 5254385 bytes, checksum: 3ac040e5f9ad13d1d9fc82f32f2f0abf (MD5) Previous issue date: 2006-08-25 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The tectonics activity on the southern border of Parna?ba Basin resulted in a wide range of brittle structures that affect siliciclastic sedimentary rocks. This tectonic activity and related faults, joints, and folds are poorly known. The main aims of this study were (1) to identify lineaments using several remotesensing systems, (2) to check how the interpretation based on these systems at several scales influence the identification of lineaments, and (3) to contribute to the knowledge of brittle tectonics in the southern border of the Parna?ba Basin. The integration of orbital and aerial systems allowed a multi-scale identification, classification, and quantification of lineaments. Maps of lineaments were elaborated in the following scales: 1:200,000 (SRTM Shuttle Radar Topographic Mission), 1:50,000 (Landsat 7 ETM+ satellite), 1:10,000 (aerial photographs) and 1:5,000 (Quickbird satellite). The classification of the features with structural significance allowed the determination of four structural sets: NW, NS, NE, and EW. They were usually identified in all remote-sensing systems. The NE-trending set was not easily identified in aerial photographs but was better visualized on images of medium-resolution systems (SRTM and Landsat 7 ETM+). The same behavior characterizes the NW-trending. The NS-and EW-trending sets were better identified on images from high-resolution systems (aerial photographs and Quickbird). The structural meaning of the lineaments was established after field work. The NEtrending set is associated with normal and strike-slip faults, including deformation bands. These are the oldest structures identified in the region and are related to the reactivation of Precambrian basement structures from the Transbrazilian Lineament. The NW-trending set represents strike-slip and subordinated normal faults. The high dispersion of this set suggests a more recent origin than the previous structures. The NW-trending set may be related to the Picos-Santa In?s Lineament. The NS-and EW-trending sets correspond to large joints (100 m 5 km long). The truncation relationships between these joint sets indicate that the EW-is older than the NS-trending set. The methodology developed by the present work is an excellent tool for the understanding of the regional and local tectonic structures in the Parna?ba basin. It helps the choice of the best remote-sensing system to identify brittle features in a poorly known sedimentary basin / A atividade tect?nica atuante na borda sudeste da Bacia do Parna?ba resultou em ampla gama de estruturas r?pteis que afetaram rochas sedimentares silicicl?sticas. Esta atividade tect?nica e as falhas, juntas e dobras s?o pouco conhecidas. Os principais objetivos deste estudo foram (1) identificar lineamentos atrav?s de sistemas de sensores remotos, (2) checar como a interpreta??o com base nestes sistemas em diversas escalas influencia a identifica??o de lineamentos, e (3) contribuir para o conhecimento da tect?nica r?ptil na borda sudeste da Bacia do Parna?ba. A integra??o de sistemas orbitais e a?reos permitiu a identifica??o, classifica??o e quantifica??o multi-escala de lineamentos. Mapas de lineamentos foram elaborados nas seguintes escalas: 1:200.000 (radar da SRTM Shuttle Radar Topographic Mission), 1:50.000 (sat?lite Landsat 7 ETM+), 1:10.000 (fotografias a?reas) e 1:5.000 (sat?lite Quickbird). A classifica??o das fei??es com significado estrutural possibilitou a determina??o de quatro conjuntos estruturais: NW, NS, NE, e EW. Eles geralmente foram identificados em todos os sistemas de sensores remotos. O conjunto NE n?o foi facilmente identificado nas fotografias a?reas. Este conjunto, bem como o NW, foram visualizados mais nitidamente nas imagens dos sistemas de m?dia resolu??o (SRTM e Landsat 7 ETM+). Os conjuntos NS e EW foram melhores identificados nos produtos de sensores de alta resolu??o (fotografias a?reas e sat?lite Quickbird). O significado estrutural dos lineamentos foi estabelecido ap?s o trabalho de campo. O conjunto NE est? associado a falhas normais e transcorrentes, inclusive bandas de deforma??o. Estas s?o as estruturas mais antigas identificadas na regi?o e s?o relacionadas ? reativa??o de estruturas do embasamento Pr?-Cambriano. O conjunto NW representa falhas trancorrentes e normais subordinadas. A dispers?o deste conjunto sugere uma origem mais recente que as estruturas inseridas no conjunto NE. O conjunto NW pode estar relacionado ao Lineamento Picos-Santa In?s. Os conjuntos NS e EW correspondem a juntas de grande porte (comprimentos de 100 m a 5 km). As rela??es de truncamento entre estes conjuntos de juntas indicam que o conjunto EW ? mais antigo que o NS. A metodologia desenvolvida pelo presente trabalho ? uma ferramenta excelente para o entendimento das estruturas regionais e locais na Bacia do Parna?ba. Isto auxilia na escolha do sistema de sensor remoto mais indicado para identificar fei??es r?pteis em uma bacia sedimentar pouco conhecida
17

Dynamic and multi-perspective risk management of construction projects using tailor-made Risk Breakdown Structures / Gestion dynamique et multi perspectives des risques pour les projets de construction : l'apport d'une arborescence hiérarchique des risques "à la carte"

Mehdizadeh, Rasool 04 June 2012 (has links)
Depuis quelques années, de nombreux travaux de recherche se sont portés sur le domaine de la gestion des risques pour les projets de construction. Les projets de construction font intervenir de nombreux acteurs dont les intérêts et les besoins doivent être pris en compte dans le système décisionnel afin d’assurer le succès du projet.Une RBS (Risk Breakdown Structure) est une représentation hiérarchisée des risques d’un projet. Elle est composée de catégories de risque qui explicitent les différents domaines pouvant être source de risque. Ce type de représentation présente de nombreux avantages, la rendant ainsi adaptée à la gestion des risques dans les projets de construction : elle offre une vision synthétique des risques, elle est compatible avec la nature dynamique et évolutive des risques et elle permet à chaque acteur du projet d’avoir sa propre vision des risques. Cependant les RBS présentent aussi des inconvénients : il n’existe pas de consensus sur la façon de les construire, la définition des catégories de risque est souvent floue et non partagée, enfin il n’y a pas de règles permettant de propager les évaluations (qualitatives ou quantitatives) dans les branches de la structure.Dans cette thèse, nous proposons une méthodologie pour le développement de RBS sur mesure, c’est à dire adaptées à l'étape et au niveau de développement du projet et permettant d'offrir un point de vue adapté aux différents acteurs. Cela permet de poser les bases d’une approche dynamique, multi-échelle, multi-perspective dans laquelle chaque acteur, peut, dans chacune des phases, se concentrer sur certains risques par une décomposition adaptée de sa RBS. Cela permet d'identifier et de gérer les risques liés au projet de construction d'une façon plus formelle, plus efficace et plus systématique.En parallèle, des efforts ont porté sur le développement d'une méthode avancée pour l'analyse et la propagation des valeurs de risque par les RBS. Le but était de développer une approche cohérente afin d’obtenir des résultats réalistes sans souffrir des faiblesses habituelles des méthodes disponibles dans la littérature. La méthode combine les approches quantitatives et qualitatives, permettant ainsi à l'utilisateur de choisir, selon l'information disponible et la précision souhaitée le choix du type d'évaluation le plus adapté.Une attention particulière a été portée quant au développement de la base de connaissances, afin d'assurer la cohérence des données. La base de connaissance est composée de trois types d’objets principaux : les événements risqués, les catégories de risque et les arbres élémentaires. Elle a été alimentée par une analyse approfondie de la littérature. Cette base de connaissances est suffisamment générale pour couvrir tous les projets de construction et suffisamment précise pour être adaptée à un projet particulier. Elle fournit un langage commun avec lequel les risques liés au projet peuvent être décrits et discutés. Le processus de construction des RBS est basé sur une logique multicritère (degré de développement, satisfaction des utilisateurs, contraste des valeurs de risque) permettant de comparer les différentes RBS entre elles. La structure de la base de connaissance est conçue de façon à faciliter sa mise à jour et ses développements ultérieurs.MOTS-CLÉS: , , construction, méthodologie, bases de données. / In recent years, intensive research and development have been done in the area of construction projects risk management. The construction projects involve numerous participants whose interests and demands need to be considered in the managerial decision-making to ensure the success of the project. Risk Breakdown Structure is a hierarchically organized depiction of the identified project risks arranged by risk categories and subcategories that identifies the various areas and causes of potential risks. This type of representation has many advantages and is a suitable tool especially for risk management of construction projects since: it offers a synthetic view on risks, each stakeholder can have his own view on the project and it is compatible with evolutionary and dynamic nature of project risks. However, RBS suffers several drawbacks such as lack of consensus on how to develop an RBS for a new project, lack of clarity and inconsistencies in definition of risk categories and lack of rules enabling transfer of qualitative/quantitative information of risks across the tree. In this PhD thesis, we propose a methodology for the development of tailor-made RBS's which are adapted to several constraints: being fitted to the stage and degree of development of the project, being able to offer different views for the different partners. This makes it possible to establish a dynamic, multi-scale and multi-perspective approach in which each partner, at each desired stage, can focus on selected specific risks and divide the RBS's up into a greater number of subcategories in specific fields. It allows to identify and manage the construction project risks in a more formal, efficient and systematic way. In parallel, efforts have been devoted to the development of an advanced method for analysis and propagation of risk values through RBS. The aim was to develop a more coherent approach in order to get more realistic results without suffering from the usual weaknesses of available methods in literature to calculate the risk value of categories in RBS. The method combines consistently the quantitative and qualitative approaches, allowing the user to choose the best one for risk assessment at any level based on the available information and required accuracy.Special care was taken in the development of the risk knowledge database in order to ensure the data's consistency. A database which has three interactive components of risk events, risk categories and micro trees, and have been developed based on a thorough analysis of literature. This knowledge base is general enough to cover all construction projects but at the same time, specific enough to be adapted to a given particular project. This database provides a common language within which the project risks can be described and discussed. The RBS rebuilding process is driven in such a way as to make it possible to compare different possible RBS's according to several criteria (degree of development, user satisfaction and highlighting the contrast of risk values). The database is constructed in such a way as to facilitate further developments and updating. / در طي سال‌هاي اخير، تحقيقات گسترده‌اي در زمينه مديريت ريسک پروژه‌هاي ساخت و ساز و زيربنايي انجام گرفته است. غالبا اين نوع از پروژه‌ها در برگيرنده تعداد زيادي ذينفع (مالک، پيمانکاران، طراحان فني و معماري، سرمايه¬گذار، بيمه‌گر و ...) مي‌باشند که مدنظر قرار دادن منافع، اهداف و مطالبات آن¬ها در اتخاذ تصميم‌ها يکي از موارد لازم براي اطمينان از موفقيت پروژه مي‌باشد.ساختار درختي ريسک (Risk Breakdown Structure) که بازنمودي طبقه¬بندي شده از ريسک‌هاي پروژه ارائه مي‌نمايد، متشکل از گروه‌ها و زير¬گروه‌هاي سازمان يافته ريسک بوده و ابزاري بسيار موثر در شناسايي منابع و آثار محتمل ريسک‌ها مي‌باشد. اين نوع باز¬نمود ريسک‌ها داراي مزاياي فراواني مي‌باشد به خصوص در مديريت ريسک پروژه‌هاي عمراني و زيربنايي. بخشي از دلايل اين مدعا عبارتند از: توانايي RBS در تجزيه وتحليل ريسک‌هاي پروژه و اينکه با استفاده از RBS هريک از اعضاي ذينفع پروژه مي‌تواند ديدگاه خاص خود را نسبت به ريسک‌هاي پروژه داشته باشد که اين قضيه با ماهيت ديناميک و تکاملي پروژه‌ها به خوبي سازگار مي‌باشد. با اين¬حال، عليرغم قابليت‌هاي فوق العاده اين ابزار، RBS داراي چندين ضعف اساسي مي‌باشد از قبيل: عدم وجود راهنما، روش و اجماع در چگونگي طراحي RBS جديد براي يک پروژه جديد با ويژه¬گي‌هاي خاص خود، وجود تعاريف مبهم و بعضا متناقض ريسک‌ها و گروه‌هاي ريسک در RBS‌هاي موجود، عدم وجود روشي مشترک و موثر براي انتقال اطلاعات کمي و کيفي وقايع ريسک بر روي ساختار درختي RBS به منظور محاسبه مقادير ريسک هر گروه ريسک.در اين رساله دکتري، روشي نوين براي طراحي RBS‌هاي سازگار براي هر پروژه يا شرايط خاص ارائه مي‌گردد. اين RBS‌ها با مقطع زماني و ميزان پيشرفت پروژه و همچنين ديدگاه‌هاي متفاوت ذينفعان پروژه نسبت به ريسک‌ها سازگار مي‌باشند. اين روش متضمن اعمال مديريت ريسک پويا و ديناميک، چند مقياسي و چند بعدي در پروژه‌ها بوده و هر يک از اعضاي پروژه در هر مقطع زمانی خاص قادر خواهد بود بر ريسک‌هاي مورد نظر خود تمرکز نموده و براي کسب اطلاعات جامعتر، هر گروه ريسک در RBS را به تعداد بيشتري زير گروه تجزيه نمايد. چنين رويه‌اي ابزار و روش لازم براي شناسايي و مديريت سيستماتيک، موثرتر و رسمي‌تر ريسک‌هاي پروژه را فراهم مي‌نمايد.همزمان با توسعه روش مذکور براي طراحي RBS‌هاي سفارشي براي هر مورد خاص، تلاش ويژه¬اي براي ابداع روشي نوين به منظور کسب نتايج واقع¬بينانه¬تر در آناليز و توزيع مقادير ريسک بر روي شاخه¬هاي RBS اعمال گرديد. روش پيشنهادي، ترکيبي سازگار از رويکرد¬هاي کمي و کيفي ارائه نموده و کاربر قادر خواهد بود بر اساس ميزان اطلاعات موجود و دقت مورد نياز بهترين گزينه را انتخاب نمايد.براي اطمينان از سازگاري اطلاعات مورد استفاده در روش¬هاي فوق الذکر و ايجاد ادبياتي مشترک واستاندارد براي توصيف و بحث پيرامون ريسک¬هاي پروژه، دقت خاصي در توسعه ديتا¬بيس (بانک اطلاعات) ريسک اتخاذ گرديد. اين پايگاه¬داده که بر اساس مطالعه و تجزيه و تحليل دقيق متون موجود، استاندارها و گزارشات فني پيرامون مديريت ريسک پروژه¬هاي عمراني تهيه گرديده است متشکل از سه بخش اساسي پويا و توسعه پذير مي¬باشد: وقايع ريسک، گروه¬هاي ريسک و ميکرو درخت¬ها. در عين جامعيت اين ديتا¬بيس براي تحت پوشش قرار دادن انواع پروژه¬هاي عمراني، ساختار اطلاعات به گونه¬اي طراحي گرديده که توسعه آن براي تمرکز بر نوع خاصي از پروژه (تونل، سازه¬هاي موقت، ...) امکان¬پذير مي¬باشد.فرايند طراحي RBS‌هاي سفارشي با بازسازي تمامي RBS‌هاي ممکن از طريق ترکيب ميکرو درخت¬هاي موجود در ديتا¬بيس آغاز گرديده و سپس براي انتخاب بهترين درخت ريسک، تمامي گزينه¬هاي ممکن به واسطه معيار¬هاي کيفيت تعريف شده RBS (ميزان توسعه ساختار درخت ريسک، تناسب ساختار RBS با مطالبات و اهداف کاربر و کنتراست مقادير ريسک بر روي شاخه¬هاي RBS) مقايسه مي¬گردند.براي تسهيل کاربرد عملي روش¬هاي ارئه شده در پروژه¬هاي واقعي، نرم افزار خاصي بر اساس تمامي مفاهيم و الگوريتم¬هاي موجود در روش-هاي توسعه داده شده تهيه گرديده است. اين نرم افزار با واسط کاربر پسند، ابتدا تمامي RBS‌هاي ممکن را توليد نموده، مقادير ريسک گروه¬هاي ريسک را محاسبه کرده و به طور اتوماتيک براي هر RBS‌ پنج فاکتور کيفيت محاسبه مي¬نمايد. در گام دوم، تمامي RBS‌هاي ايجاد شده با استفاده از يکي از روش¬هاي تصميم¬گيري چند¬معياري رتبه¬بندي شده، کاربر قادر خواهد بود بهترين RBS‌ را انتخاب نمايد. نرم افزار قادر است به طور گرافيکي ساختار درختي تمامي RBS‌هاي طراحي شده را به همراه مقادير ريسک محاسبه شده و توزيع وقايع ريسک بر روي شاخه¬هاي RBS‌ نمايش دهد.

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