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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

[en] A STUDY ON EVALUATION OF IMPLEMENTATION OF BLAST IN A DISTRIBUTED ENVIRONMENT / [pt] UM ESTUDO SOBRE AVALIAÇÃO DA EXECUÇÃO DO BLAST EM AMBIENTES DISTRIBUÍDOS

PAULO ROBERTO GOMES 12 July 2016 (has links)
[pt] Ferramentas BLAST são normalmente utilizadas para efetuar comparações entre sequências de DNA, RNA e proteínas. No entanto, face ao crescimento exponencial das bases biológicas, existe uma preocupação quanto ao desempenho do BLAST, mesmo considerando os equipamentos de grande capacidade computacional hoje existente. Considerando tal fato, algumas ferramentas capazes de executar o BLAST em ambientes distribuídos, tais como clusters e grids, vêm sendo desenvolvidas de modo a acelerar consideravelmente a sua execução. No entanto, até o presente momento, não foi constatado, na literatura existente, nenhum estudo com o objetivo de comprar o desempenho entre essas ferramentas. A avaliação de desempenho dessas ferramentas é normalmente efetuada de forma isolada, considerando apenas o tempo de execução (elapsed time), em situações diversas, como, por exemplo, variando o número de nós em que a ferramenta BLAST é executada.. Almejando uma investigação mais detalhada, principalmente no que diz respeito a avaliação de desempenho do BLAST em ambientes distribuídos, a presente dissertação tem como um dos seus objetivos efetuar um estudo detalhado sobre como comparar o desempenho do BLAST em um ambiente distribuído, considerando para tal, a avaliação de três ferramentas BLAST, dentre elas balaBLAST, desenvolvida no Laborátorio de Bioinformática da PUC-RIO. O segundo objetivo é verificar a eficácia do balanceamento de carga efetuada pela ferramenta balaBLAST. / [en] BLAST tools are typically used to make comparisons between sequences of DNA, RNA and proteins. However, given the exponential growth of the biological databases, there is concern about the performance of BLAST, even considering the equipment of large computing power that exists today. Considering this fact, some tools to run BLAST in distributed environments such as clusters and grids, have been developed to greatly accelerate its performance. However, until now, has not been found in existing literature, no study in order to compare the performance between these tools. The performance evaluation of these tools is usually done in isolation, considering only the execution time (elapsed time) in different situations, for example, varying the number of nodes in the tool BLAST runs. Craving a more detailed investigation, especially with regard to performance evalution of BLAST in distributed environments, this dissertation has as one of your goals make a detailed study to compare the performance of BLAST in a distributed enviroment, considering for such the evaluation of three tools BLAST, among them the balaBLAST developed in the Bioinformatics Laboratory of PUC-Rio. The second objective is to verify the effectiveness of load balancing performed by the tool balaBLAST.
12

[en] MACHINE LEARNING TECHNIQUES FOR RESOURCE MANAGEMENT IN MOBILE SELF-ORGANIZING NETWORKS / [pt] TÉCNICAS DE APRENDIZAGEM PARA GERÊNCIA DE RECURSOS EM REDES MÓVEIS HETEROGÊNEAS E AUTO-ORGANIZÁVEIS

CESAR AUGUSTO SIERRA FRANCO 20 May 2021 (has links)
[pt] Os sistemas de comunicações móveis atuais vêm enfrentando novos desafios, marcados pelo aumento do uso de novos dispositivos e pela mudança nos padrões de consumo de banda causada pelas aplicações emergentes. É por isso que a indústria de comunicações e a comunidade acadêmica vêm trabalhando tanto nas dificuldades apresentadas nas redes móveis atuais quanto nos desafios técnicos para o desenvolvimento dos esperados sistemas de quinta geração (5G). O grande aumento dos elementos da rede de acesso rádio e a implementação de cenários heterogêneos (macro e pico eNBs, Relay Nodes, etc.) são duas das principais abordagens utilizadas para melhorar a capacidade da rede. No entanto, esse acréscimo de elementos ou, densificação, traz consigo um aumento nos custos e na complexidade nas tarefas de operação e gerenciamento do sistema, já que os novos elementos de rede precisam ser adaptados, configurados e gerenciados continuamente para garantir e aumentar a eficiência da rede, melhorando a qualidade nos serviços oferecidos aos usuários. Este trabalho de pesquisa propõe a inclusão de mecanismos cognitivos, incluindo técnicas de adaptação, nas arquiteturas das redes de acesso móvel. O trabalho propõe igualmente novos mecanismos de auto-organização (Self Organizing Networks, SON) para o balanceamento de carga, empregando modelos dinâmicos capazes de tomar decisões inteligentes e aprender a partir de experiências para atingir os objetivos de desempenho desejados. / [en] Today s mobile communications systems are facing new challenges, triggered by the increased use of new devices and the growth of bandwidth hungry applications. This is why over the last years, the telecommunication industry and academic communities have been focused on research and development of technologies for the upcoming 5th generation mobile systems (5G). Among the potential candidates, network densification has attracted growing attention as a key mechanism to fulfill the objective proposed in 5G, by increasing the number of radio-base stations (on the coverage area) and introducing an additional layer of low-power access nodes (e.g., Femto, picocells, relay nodes). However, this approach has also posed new challenges in network configuration, management, and optimization tasks to ensure and increase the mobile network efficiency. This research proposes the inclusion of cognitive mechanisms and adaptive techniques in the architectures of mobile radio access networks. This work also proposes new self-organizing (SON) functions for load balancing, enhanced with capabilities of learning from previous experiences to achieve future desired performance goals.
13

Etude d’un système hybride de kitting semi-automatisé dans le secteur automobile : conception du système et modèle d’optimisation pour l’affectation des pièces aux pickers / Analysis of a hybrid robot–operator kitting system in the automotive industry : design and optimal assignment of parts to pickers

Boudella, Mohamed El Amine 19 September 2018 (has links)
Cette thèse, réalisée en collaboration avec le Groupe Renault dans le cadre d’un projet d’automatisation du kitting, s’intéresse à l’optimisation du processus de kitting en termes de maximisation du temps de cycle. Pour cela, nous étudions différentes configurations de système de kitting hybride avec robots(s) et opérateur(s) travaillant en série et séparés par un stock de découplage. Le(s) robot(s) commence(nt) la préparation des kits de pièces puis le(s) opérateur(s) se trouvant dans la partie manuelle du kitting récupère(nt) cette préparation et la complète(nt) avec les pièces affectées à cette zone.Notre objectif est de développer un outil d’aide à la décision permettant d’évaluer la performance d’un kitting hybride et de simuler son fonctionnement dans une configuration donnée (layout, politique de picking, etc.) avant son déploiement physique.Tout d’abord, à travers une modélisation des opérationsélémentaires de kitting effectuées par des robots et des opérateurs (prise et dépose, déplacement, etc.), nous proposons un modèle de temps de cycle permettant d’évaluer la performance du système hybride en termes de temps de cycle. Ensuite, nous développons un modèle d’affectation de pièces (PLMNE) permettant de les répartir entre kitting robotisé et manuel. L’objectif est de minimiser les temps de cycle et d’équilibrer la charge de travail entre les deux modes de kitting. Le modèle est appliqué à deux études de cas pratiques issues d’une usine Renault. Les résultats permettent d’identifier les paramètres qui impactent le plus les temps de cycle et le choix d’affectation des pièces entre kitting automatisé et manuel. Enfin, nous développons un modèle de simulation afin de calculer la taille optimale du stock de découplage entre kitting automatisé et manuel dans le but de maximiser la cadence du système hybride de kitting. / In this thesis, conducted with Renault in the context of a kitting automation project, we are interested in the optimisation of kitting processes in terms of cycle time maximisation. To do so, we study different configurations of hybrid robot-operator kitting systems where robots (two types of robots considered) and operators are connected in series by an intermediate buffer (to decouple their activities). The robotic kitting area starts the preparation of kits then the operators in the manual kitting area retrieve the preparation of robots and complete with the remaining parts.Our objective is to develop a decision-making tool that assesses the hybrid system performance in a given configuration (layout, picking policy, etc.).First, through a modelling of elementary kitting operations performed by robots and operators (pick and place, travel, etc.), we develop a cycle time model to assess the performance of hybrid kitting systems. Then, we develop an assignment model that assigns parts (formulated as a mixed integer linear programming (MILP) problem) either to robotic or manual kitting areas with the objective of minimising cycle times and balancing workload between them. The model is applied to two case studies pertaining to a Renault plant. This analysis identifies the parameters that influence cycle times and the choice between robotic and manual kitting. Finally, we develop a simulation model to find the optimal buffer size between robotic and manual kitting so that throughput is maximised.
14

單元製造系統之人力配置策略研究 / A Study of Operator A ssignments Flexibility within and betwe en Cellular Manufacturing Systems

張毓欣 Unknown Date (has links)
由於少量多樣的生產趨勢,單元製造系統(Cellular Manufacturing Systems)已成為目前製造業的重點之一。在單元製造系統中,具有多種技能的員工是必備的條件,如何有效的配置人力策略即為本研究的重點。人力配置策略包含了指定式(由單一操作員負責某件工作)、共享式(由兩名或兩名以上操作員共同負責某件工作)及混合式人力配置策略(同時使用指定式和共享式兩種策略),其中,共享式和混合式的人力配置策略可稱為彈性人力配置策略。要使用彈性人力配置策略,需要有人力彈性(Labor Flexibility)。   所謂的人力彈性在單元製造系統可分為兩個方向:(1)單元間的人力彈性(Inter-Cell Labor Flexibility),即不同單元間的轉換能力,(2)單元內的人力彈性(Intra-Cell Labor Flexibility),即單元內不同工作間的轉換能力。本研究分為兩個主要部份,分別探討在單元間採用彈性人力配置策略和在單元內採用彈性人力配置策略對於工作量平衡程度、工作量共享程度和績效表現的影響。   根據研究結果,在單元內採用彈性的人力配置策略對於操作員間的工作量平衡和績效表現皆有直接且正向影響,但隨著操作員數目的減少,彈性的人力配置策略對於績效表現之影響減弱、甚至變為負向效果;在單元間採用彈性的人力配置策略之效果和在單元內採用彈性的人力配置策略相似,對操作員間的工作量平衡和績效表現亦有直接且正向影響,且隨著單元數增加,在單元間採用彈性的人力配置策略對績效表現的影響增強。本研究之結果可做為運用彈性的人力配置策略以及規劃交互訓練時的參考方向,並可用此架構來預測績效改變。 / The object of the research is to study agile labor assignments in cellular manufacturing systems by intra-cell and inter-cell operator’s mobility. There are three labor assignments strategies including dedicated (only one operator is responsible for a work), shared (two or more than two operators are responsible for a work), and combined assignment (using both of dedicated assignment and shared assignment). Different assignments lead to different workload balancing, workload sharing and performance. The research builds a simulate framework which includes operators’ moving rule, proposition of empirical study and index of workload balancing and workload sharing. According the result of research, applying intra-cell operator’s mobility can improve operator’s workload balancing and performance. Nevertheless, the relationship of intra-cell operator’s mobility and performance would decrease with decreasing of labor limited. The impact of inter-cell operator’s mobility is similar to intra-cell operator’s mobility, but it would increase with increase of complexity. The simulate framework which pass through the testing can use in an actual company case, provide a direction of how to use labor assignments, and forecast the impact of using agile labor assignment.
15

Qualification Management and Closed-Loop Production Planning in Semiconductor Manufacturing / Gestion des qualifications et planification de production en boucle fermée dans la fabrications des semiconducteurs

Rowshannahad, Mehdi 26 May 2015 (has links)
La thèse est composée de deux parties. La première partie traite de la gestion des qualifications dans l'industrie des semi-conducteurs. La contrainte de qualification définit l'éligibilité d'une machine à processer un produit. La gestion des qualifications nécessite de résoudre un problème d'allocation et d'équilibrage des charges sur des machines parallèles non-identiques et partiellement reconfigurables. Nous avons défini et introduit des indicateurs pour la gestion des qualifications en tenant compte de la capacité des équipements ainsi que la contrainte de regroupements de lots (batching). Plusieurs algorithmes d'équilibrage de charge sont proposés et validés pour le calcul de la charge optimale sur un parc d'équipements. Ce concept est industrialisé au sein de l'entreprise Soitec et fait partie du processus de prise de décision.La deuxième partie de la thèse porte sur la planification de production en boucle fermée. Le processus de fabrication des plaques SOI à Soitec s'appuie sur la Technologie Smart-Cut. En utilisant cette technologie, une des deux matières premières peut être réutilisée à plusieurs reprises pour la fabrication des produits finis. Le couplage de deux lignes de production crée un système manufacturier en boucle fermée. Nous avons proposé un modèle de dimensionnement de lots original pour la planification de production de ce système manufacturier, que nous avons validé avec des données industrielles. En se basant sur le problème industriel, un problème mono-produit et sans contrainte de capacité est défini, analysé et résolu pour une version simplifiée du problème. / In the first part, we take a binding restriction, called qualification, present in semiconductor manufacturing as a lever for increasing flexibility and optimizing capacity utilization. A qualification determines the processing authorization of a product on a machine (like an eligibility constraint). In order to define the best qualification, the production volume should be allocated to parallel non-identical machines which are partially reconfigurable. Capacitated flexibility measures are introduced to define the best qualification which increases machine capacity utilization at most. Batching is another industrial constraint encountered in semiconductor industry. It influences workload balancing and qualification management. Several workload balancing algorithms are proposed to find the optimal workload balance of a workcenter. Variability measures are also proposed to evaluate the workload variability of a workcenter. The second part deals with closed-loop production planning. Soitec uses Smart-Cut Technology to fabricate SOI wafers. Using this technology, one of the two raw materials used to fabricate SOI wafers can be reused several times to make other SOI wafers. However, before coming back to the SOI fabrication line, the used raw material (by-product) must be reworked in another production line. An original closed-loop production planning model adapted to the supply chain specificities of Soitec is proposed, and is validated using industrial data. Based on this industrial model, a single-item uncapacitated closed-loop lot-sizing model is defined, analyzed, and a dynamic programming algorithm is proposed for a simplified version of the problem.

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