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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.
681

Escola de tempo integral e currículo: desafios e perspectivas do núcleo gestor sobre o Programa do Sistema Municipal de Educação de Mogi das Cruzes SP, no período de 2009 a 2013

Santos, Juliana de Paula Guedes de Melo 02 December 2014 (has links)
Made available in DSpace on 2016-04-27T14:31:29Z (GMT). No. of bitstreams: 1 Juliana de Paula Guedes de Melo Santos.pdf: 4219434 bytes, checksum: a33a651da341a580dbf805b78d2fde91 (MD5) Previous issue date: 2014-12-02 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The setting of this research are the Schools Full Time , Primary Education , the Municipal Education System in the city of Mogi das Cruzes - SP , during the years 2009 to 2013. The structuring and consolidation of this school model emerged in response to broader social issues involving risk and vulnerability that are exposed schoolchildren . However , the organizational complexity of both teaching , as administrative , restructuring and consolidation required for this proposed school emphasizes problem investigated here are the challenges and prospects of the core members of the manager about his own work and curricular issues related to School Time integral . The central objective is guided to identify the perceptions of members of the core manager issues related to the prescribed curriculum and the lived curriculum , this post considering time, space , text and context. Data collection was conducted from questionnaires completed by members of the Center Manager - director , deputy director and educational coordinator - Four Schools Full Time , located in one of the districts of the city . This cut was chosen by the multiplicity of characteristics of schools that are ( number of students per school, type of building construction and date of inclusion in School Full Time Program of the municipality ) , and thus depict the differences found within each school units and justify the complexity of the work of the Center Manager of each of the schools. The results were analyzed in light of the theories of several authors and is intended to constitute up major collaborative reflection of the structure and organization of these schools elements , since the announced expansion of the program in the city of Mogi das Cruzes - SP , government city for the next year as a way to fulfill the National Education Plan / O cenário desta pesquisa são as Escolas de Tempo Integral, de Ensino Fundamental, do Sistema Municipal de Educação, da cidade de Mogi das Cruzes SP, durante os anos de 2009 a 2013. A estruturação e consolidação deste projeto de escola emergiu como resposta a questões sociais amplas que envolvem o risco e a vulnerabilidade a que estão expostas as crianças em idade escolar. Contudo, a complexidade organizacional tanto pedagógica, quanto administrativa, exigida para estruturação e consolidação desta proposta de escola enfatiza o problema aqui investigado que são os desafios e perspectivas dos membros do núcleo gestor acerca de seu próprio trabalho e das questões curriculares relativas à Escola de Tempo Integral. O objetivo central está pautado em identificar na percepção dos membros do núcleo gestor questões relacionadas ao currículo prescrito e ao currículo vivido, isto posto considerando-se tempos, espaços, texto e contexto. A coleta de dados foi realizada a partir de questionários respondidos pelos integrantes do Núcleo Gestor diretor, vice-diretor e coordenador pedagógico de Escolas de Tempo Integral, localizadas em um dos Distritos da cidade. Este recorte foi escolhido pela multiplicidade de características das escolas que o constituem (número de alunos por escola, tipo de construção predial e data de inclusão no Programa Escola de Tempo Integral do município), e que desta maneira, retratam as diferenças encontradas no interior de cada uma das unidades escolares e justificam a complexidade do trabalho do Núcleo Gestor nessas escolas. Os resultados obtidos foram analisados à luz das teorias de diversos autores e pretende-se que constituam-se importantes elementos colaborativos à reflexão da estruturação e organização das referidas escolas, visto a anunciada ampliação do Programa na cidade de Mogi das Cruzes SP, pelo governo municipal para os próximos anos, como forma de cumprimento ao Plano Nacional de Educação
682

Analyse expérimentale et modélisation du bruit haute fréquence des transistors bipolaires à hétérojonctions SiGe et InGaAs/InP pour les applications très hautes fréquences / Experimental analysis and modelling of high frequency noise in SiGe and InGaAs/InP heterojunction bipolar transistors for high frequency applications

Ramirez-garcia, Eloy 20 June 2011 (has links)
Le développement des technologies de communication et de l’information nécessite des composants semi-conducteurs ultrarapides et à faible niveau de bruit. Les transistors bipolaires à hétérojonction (TBH) sont des dispositifs qui visent des applications à hautes fréquences et qui peuvent satisfaire ces conditions. L’objet de cette thèse est l’étude expérimentale et la modélisation du bruit haute fréquence des TBH Si/SiGe:C (technologie STMicroelectronics) et InP/InGaAs (III-V Lab Alcatel-Thales).Accompagné d’un état de l’art des performances dynamiques des différentes technologies de TBH, le chapitre I rappelle brièvement le fonctionnement et la caractérisation des TBH en régime statique et dynamique. La première partie du chapitre II donne la description des deux types de TBH, avec l’analyse des performances dynamiques et statiques en fonction des variations technologiques de ceux-ci (composition de la base du TBH SiGe:C, réduction des dimensions latérales du TBH InGaAs). Avec l’aide d’une modélisation hydrodynamique, la seconde partie montre l’avantage d’une composition en germanium de 15-25% dans la base du TBH SiGe pour atteindre les meilleurs performances dynamiques. Le chapitre III synthétise des analyses statiques et dynamiques réalisées à basse température permettant de déterminer le poids relatif des temps de transit et des temps de charge dans la limitation des performances des TBH. L’analyse expérimentale et la modélisation analytique du bruit haute fréquence des deux types de TBH sont présentées en chapitre IV. La modélisation permet de mettre en évidence l’influence de la défocalisation du courant, de l’auto-échauffement, de la nature de l’hétérojonction base-émetteur sur le bruit haute fréquence. Une estimation des performances en bruit à basse température des deux types de TBH est obtenues avec les modèles électriques. / In order to fulfil the roadmap for the development of telecommunication and information technologies (TIC), low noise level and very fast semiconductor devices are required. Heterojunction bipolar transistor has demonstrated excellent high frequency performances and becomes a candidate to address TIC roadmap. This work deals with experimental analysis and high frequency noise modelling of Si/SiGe:C HBT (STMicroelectronics tech.) and InP/InGaAs HBT (III-V Lab Alcatel-Thales).Chapter I introduces the basic concepts of HBTs operation and the characterization at high-frequency. This chapter summarizes the high frequency performances of many state-of-the-art HBT technologies. The first part of chapter II describes the two HBT sets, with paying attention on the impact of the base composition (SiGe:C) or the lateral reduction of the device (InGaAs) on static and dynamic performances. Based on TCAD modelling, the second part shows that a 15-25% germanium composition profile in the base is able to reach highest dynamic performances. Chapter III summarizes the static and dynamic results at low temperature, giving a separation of the intrinsic transit times and charging times involved into the performance limitation. Chapter IV presents noise measurements and the derivation of high frequency noise analytical models. These models highlight the impact of the current crowding and the self-heating effects, and the influence of the base-emitter heterojunction on the high frequency noise. According to these models the high frequency noise performances are estimated at low temperature for both HBT technologies.
683

Otimização do processo de inserção automática de componentes eletrônicos empregando a técnica de times assíncronos. / Using A-Teams to optimize automatic insertion of electronic components.

Cesar Scarpini Rabak 22 June 1999 (has links)
Máquinas insersoras de componentes são utilizadas na indústria eletrônica moderna para a montagem automática de placas de circuito impresso. Com a competição acirrada, há necessidade de se buscar todas as oportunidades para diminuir custos e aumentar a produtividade na exploração desses equipamentos. Neste trabalho, foi proposto um procedimento de otimização do processo de inserção da máquina insersora AVK da Panasonic, implementado em um sistema baseado na técnica de times assíncronos (A-Teams). Foram realizados testes com exemplos de placas de circuito impresso empregadas por uma indústria do ramo e problemas sintéticos para avaliar o desempenho do sistema. / Component inserting machines are employed in the modern electronics industry for the automatic assembly of printed circuit boards. Due the fierce competition, there is a need to search for all opportunities to reduce costs and increase the productivity in the exploitation of these equipment. In this work we propose an optimization procedure for the insertion process of the AVK Panasonic inserting machine, implemented in a system based on asynchronous teams (A-Teams). Tests were conducted using as examples both printed circuit boards used by a particular industry of the realm and synthetic problems for the evaluation of the system.
684

Sarcopenia e dependência para relaização das atividades básicas da vida diária de idosos domiciliados no município de São Paulo - Saúde, Bem-estar e Envelhecimento (2000 e 2006) / Sarcopenia and dependency to perform activities of daily living in elderly domiciled in the city of São Paulo: SABE Survey - Health, Well-being and Aging (2000 e 2006)

Luís Alberto Gobbo 19 March 2012 (has links)
Introdução: A sarcopenia é caracterizada pela redução da força e massa muscular (MM), e acompanhada pelo declínio da capacidade funcional, em idosos, e sua associação com dependência para realização das atividades básicas da vida diária (ABVD) tem sido relatada na literatura internacional, entretanto, há escassez de informações sobre o tema no Brasil. Objetivo: Estimar a associação entre sarcopenia e dependência para a realização das ABVD, em idosos domiciliados no município de São Paulo, segundo sexo. Casuística e métodos: Foram analisados idosos ( 60 anos), de ambos os sexos, do Estudo SABE, longitudinal, epidemiológico e de base domiciliar, realizado no município de São Paulo, em 2000 e 2006, e que, em 2000, não apresentaram dependência. A variável sarcopenia foi definida por meio de três componentes: desempenho no teste de sentar e levantar de uma cadeira (SeL), categorizado em baixo (tempo percentil 75, segundo sexo), e normal (< percentil 75); pela força de preensão manual (FPM), categorizada em baixa (força percentil 25, segundo índice de massa corporal e sexo) e normal (> percentil 25); e massa muscular (MM), categorizada em baixa ( percentil 20, segundo sexo) e normal (> percentil 20), sendo diagnosticados sarcopênicos, idosos que apresentaram, simultaneamente, baixo desempenho e baixa MM, ou, então, desempenho normal, mas, baixas FPM e MM. A dependência para a realização das ABVD foi referidas pelos idosos, em 2006, sendo considerando dependentes, aqueles que responderam positivamente, para, pelo menos uma questão referente à dependência. As variáveis de controle foram sexo, grupos etários (60-74 e 75 anos), etnia (caucasianos, asiáticos, outros), número de doenças referidas (1 ou > 1). Resultados: Dos idosos sobreviventes, 799 apresentaram todos os dados necessários ao estudo (60,3 por cento mulheres, 85,6 por cento < 75 anos). Foram identificados como sarcopênicos, em 2000, 8,9 por cento dos idosos (homens = 8,3 por cento ; mulheres = 9,3 por cento ), e dependentes para a realização das ABVD, em 2006, 7 por cento (homens = 6,5 por cento ; mulheres = 7,3 por cento ). Idosos sarcopênicos apresentaram chance 3,13 vezes maior, para dependência (IC 95 por cento 1,67-5,87), em 2006, ajustado pelas demais variáveis, em relação aos não sarcopênicos. Quanto ao sexo, os homens sarcopênicos apresentaram chance 4,12 vezes maior (IC 95 por cento 1,28-13,30), para dependência, em 2006, enquanto as mulheres sarcopênicas apresentaram chance 2,77 vezes maior (IC 95 por cento 1,23-6,24). Conclusão: Aproximadamente 9 por cento dos idosos do município de São Paulo foram identificados como sarcopênicos, em 2000. Idosos sarcopênicos apresentaram chance maior de dependência para a realização das ABVD, em 2006, em particular, os homens / Introduction: Sarcopenia is characterized by reduced muscle mass (MM) and strength, and it is accompanied by a decline in functional capacity in elderly. Its association with dependence to perform activities of daily living (ADL) has been reported in international literature, however,there is limited information about the theme, in Brazil. Purpose: To estimate the association between sarcopenia and dependence to perform ADL, in elderly domiciled in the city of São Paulo, according to gender. Methodology: Elderly ( 60 anos) of both genders, who were not dependent in 2000, from the SABE Survey, a home-based, longitudinal and epidemiologic study, performed in the city of São Paulo, in 2000 and 2006, were analyzed. Sarcopenia was defined by three components: performance in the sit and rise from a chair test (S&R), categorized as low (time 75th percentile according to sex) and normal (<75th percentile); by handgrip strength (HS), categorized as low (strength 25 percentile, according to body mass index and gender) and normal (> 25th percentile); and muscle mass (MM), categorized as low ( 20th percentile, by sex) and normal (> 20th percentile); where diagnosed sarcopenic elderly who had both poor performance and low MM , or normal performance, but low HS and MM. Dependence to perform ADL, referred by the elderly, in 2006, being considered dependents those who answered, positively, for at least, one question related to dependence. Control variables were: sex, age groups (60-74 e 75 anos), ethnicity (caucasian, asian, others), number of referred diseases (1 ou > 1). Results: Of the survivors, 799 presented all data for the study (60.3 per cent women, 85.6 per cent < 75 years old). It was identified as sarcopenic, in 2000, 8.9 per cent of the elderly (men = 8.3 per cent ; women = 9.3 per cent ), and dependents to perform ADL, in 2006, 7 per cent (men = 6.5 per cent ; women = 7.3 per cent ). Those diagnosed with sarcopenia, in 2000, presented an odds ratio 3.13 times higher, for dependence (CI 95 per cent 1.67-5.87), in 2006, adjusted for other variables. According to gender, sarcopenic men presented an odds ratio 4.12 times higher (CI 95 per cent 1.28-13.30), for dependence, in 2006, while sarcopenic women present odds ratio 2.77 times higher (CI 95 per cent 1.23-6.24). Conclusion: Approximately 9 per cent of the elderly in São Paulo were identified as sarcopenic, in 2000. Sarcopenic elderly presented higher chance of dependency to perform ADL in 2006, particularly men
685

Semiklasická energie eliptické Nambuovy-Gotovy struny / Semi-classical energy of elliptic Nambu-Goto string

Kozoň, Marek January 2018 (has links)
Po zhrnutí potrebných teoretických základov a predošlého výskumu v ob- lasti, prezentujeme semi-klasickú kvantovaciu schému pre uzavretú Nambuovu- Gotovu strunu. Týmto zovšeobecňujeme predošlú prácu, ktorá bola vykonaná pre otvorenú strunu a uzavretú strunu kruhového tvaru. Pomocou metód kvan- tovej teórie po©a v zakrivených priestoročasoch počítame strednú hodnotu vo©- ného Hamiltoniánu struny rotujúcej v dvoch na seba kolmých priestorových rovinách v priestoročase všeobecnej dimenzie. Táto hodnota je priamo úmerná kvantovej korekcii k celkovej energii struny, ktorá má formu tzv. Reggeovho interceptu. Výslednú hodnotu Reggeovho interceptu porovnávame s predošlým výskumom. Taktiež uvádzame porovnanie získaného spektra fyzikálnych stavov struny kvantovanej našou metódou so spektrom odvodeným pomocou kovariant- ného kvantovania. 1
686

Um modelo proativo de antecipação de ações de times de resposta rápida baseado em análise preditiva

Dias, Fábio de Oliveira 17 February 2017 (has links)
Submitted by Silvana Teresinha Dornelles Studzinski (sstudzinski) on 2017-04-19T15:55:11Z No. of bitstreams: 1 Fábio de Oliveira Dias_.pdf: 3212992 bytes, checksum: 687279fc82a1e707a3ba09c241b5e09b (MD5) / Made available in DSpace on 2017-04-19T15:55:11Z (GMT). No. of bitstreams: 1 Fábio de Oliveira Dias_.pdf: 3212992 bytes, checksum: 687279fc82a1e707a3ba09c241b5e09b (MD5) Previous issue date: 2017-02-17 / Nenhuma / A computação móvel e ubíqua tem propiciado o advento de soluções que permitem o monitoramento em tempo real de sinais provenientes de sensores e o seu processamento por aplicações que podem executar ações de acordo com as condições encontradas. Esta característica possibilita o uso da tecnologia para o monitoramento de condições de saúde de pacientes, denominado de cuidados ubíquos. Em diversas situações, a fim de salvar vidas de pacientes, é necessária a análise de seus sinais vitais de forma a prevenir eventuais colapsos. Este trabalho se insere nestas condições, estando voltado para a antecipação de ações de times de resposta rápida baseado em análise preditiva, propondo o modelo Predictvs. Um Time de Resposta Rápida busca prevenir mortes de pacientes que tenham piora clínica fora de ambientes de Unidades de Tratamento Intensivo em hospitais. De forma diversa dos trabalhos relacionados, que se preocupam apenas com ambientes de tratamento intensivo, o modelo Predictvs busca antecipar ações dos times de resposta rápida, através da análise dos sinais vitais dos pacientes com o uso de escores de alerta precoce e regressão linear. A contribuição científica do modelo é dada em virtude da possibilidade de efetuar a predição em tempo real de possíveis situações de colapso dos pacientes através do monitoramento e análise dos sinais vitais. A avaliação do Predictvs foi efetuada com a utilização de cenários, com a implementação de um protótipo e através de diversas simulações. Análises efetuadas com cerca de 228000 medições provenientes de um dataset público apresentaram bons resultados, onde a precisão da predição para a medição seguinte se mostrou bastante alta, atingindo mais de 99% no caso da frequência cardíaca e 100% na saturação de oxigênio arterial, ultrapassando 95% nos demais sinais vitais. Além disso, o índice de falsos negativos foi consideravelmente baixo, atingindo menos de 1% na frequência cardíaca e na saturação de oxigênio arterial. O índice de falsos positivos também foi baixo, embora não tanto quanto o de falsos negativos. No entanto, predições para três ou mais medições futuras mostram queda na precisão (mesmo demonstrando valores de acerto relativamente expressivos, com diversos sinais fisiológicos acima de 98%) e aumento do número de falsos negativos e, principalmente, de falsos positivos. / The mobile and ubiquitous computing has allowed the emergence of solutions that enable real-time monitoring of signals coming from sensors and processing for applications that can perform actions according to the conditions found. This feature enables the use of this technology for monitoring health conditions of patients, called ubiquitous healthcare. In several situations, in order to save his lives, it is necessary to analyze the vital signs of patients to prevent any collapses. This work is part of these conditions and is aimed at anticipating the actions of rapid response teams based on predictive analysis, proposing the Predictvs model. A Rapid Response Team intends to prevent deaths in patients who have clinical deterioration outside of intensive care units in hospitals environments. Differently of related works, which are concerned only with intensive care environments, the Predictvs model seeks to anticipate the actions of teams of rapid response through the analysis of vital signs of patients with the use of early warning scores and linear regression. The scientific contribution of the presented model is that we could better predict possible collapse situations of patients, through the monitoring and analysis of vital signs. The Predictvs evaluation was performed with the use of scenarios, implementation of a prototype and several simulations. Analyzes performed with about 228,000 measurements from a public dataset showed good results, where the accuracy of the prediction for the next measurement was very high, reaching more than 99% in the case of heart rate and 100% in arterial oxygen saturation, surpassing 95% in other vital signs. In addition, the false negative index was considerably lower, reaching less than 1% in heart rate and arterial oxygen saturation. The rate of false positives was also low, although not so much as that of false negatives. However, predictions for three or more future measurements show a drop in accuracy (even showing relatively expressive set values with several physiological signals above 98%) and an increase in the number of false negatives and, mainly, false positives.
687

Culte et sanctuaires d'Asclépios dans les îles Egéennes et dans les cités côtières d'Asie Mineure (IV° s. a. C. - III° s. ap. C.) / The cult and the sanctuaries of Asclepius inside the Aegean Sea islands and in Asia minor (IV th BC - III th s AD)

Piguet, Emilie 23 November 2012 (has links)
Aucune région du monde gréco-romain n’est véritablement restée à l’écart de ladiffusion du culte d’Asclépios, au point qu’au IIe s. p.C., on ne dénombre pas moins de 320Asclepieia. A partir du IVe s. a.C. – ou du moins c’est à ce moment que nous en avons destraces effectives – et pendant toute l’époque hellénistique, le culte se propage notamment dansle monde insulaire et dans les cités côtières d’Asie Mineure, ce qui donne lieu à laconstruction de complexes parmi les plus célèbres du monde antique (Cos, Pergame, Lébèna),mais aussi une foule de sanctuaires moins importants dont l’influence est restéeessentiellement locale ou régionale. Notre thèse porte donc sur l’étude du culte et dessanctuaires d’Asclépios dans les îles égéennes et sur les côtes occidentales de l’Asie Mineureà l’époque hellénistique et au Haut-Empire romain, essentiellement à partir de ladocumentation épigraphique. Plusieurs thèmes de recherche sont développés : notamment lesétapes de la diffusion et l’origine du culte d’Asclépios ; le rôle économique, politique et socialet la gestion des sanctuaires ; le dieu (épiclèses, fonctions, famille mythique, relations avec lessouverains hellénistiques et les empereurs) et son culte (modalités et actes constitutifs) ; lepersonnel religieux, les individus et les groupes sociaux fréquentant les sanctuaires ; lesmotifs pour lesquels ces centres furent des lieux de « pèlerinage » célèbres et enfin lesinteractions entre savoirs médicaux profanes et puissance divine de guérison. / No region of the Greco-Roman world really stayed away from the distribution ofAsclepius’ cult, to the point that in IIth s p.C., we count not less than 320 Asclepieia. FromIVth s a.C. - or at least this is when we have it effective tracks - and during all the Hellenisticperiod, the cult propagates in the Aegean islands and in the coastal cities of Asia Minor. Inthis time, the complexes among the most famous of the antique world (Kos, Pergamon,Lebena) are built, as well as of numerous less important sanctuaries the influence of whichremained essentially local or regional. In our thesis, we study the Asclepius' cult and hissanctuaries in the Aegean islands and on the western coast of Asia Minor in the Hellenisticand Roman times, essentially from the epigraphic documentation. Several themes aredeveloped : the stages of the distribution and the origin of Asclepius' cult ; the economic,political and social role and the management of sanctuaries ; the god (epithets, functions,mythical family, relations with the Hellenistic sovereigns and the emperors) and his cult ; theclergy, the individuals and the social groups frequenting sanctuaries ; the motives for whichthese centers were famous places of "pilgrimage" and the interactions between profanemedical knowledges and divine power of healing.
688

Contribution à l'ordonnancement d'ateliers avec ressources de transports / Contribution to job shop scheduling problems with transport resources

Zhang, Qiao 25 July 2012 (has links)
Nos travaux concernent l’étude d’une extension d’un problème d’ordonnancement bien connu sous l’appellation job shop. Nous appelons cette extension le General Flexible Job Shop Scheduling Problem (GFJSSP). Celui-ci se rencontre dans différents types d’ateliers ayant comme caractéristique commune d’être soumis à des contraintes dues à des ressources de transport. Le GFJSSP se caractérise par l’intégration de machines et robots flexibles. Le terme General induit par ailleurs la présence de robots dont la capacité est supposée unitaire dans notre étude, des temps opératoires bornés, et la possibilité de prise en compte d’emplacements de stockage spécifiques. Après avoir défini l’atelier et le problème correspondant à cette extension, nous avons proposé deux modélisations du GFJSSP ainsi défini : une première modélisation mathématique linéaire, et une modélisation graphique, qui correspond à une généralisation du graphe disjonctif couramment utilisé pour les problèmes de job shop. Nous avons ensuite abordé la résolution suivant deux étapes : tout d’abord en nous focalisant sur l’aspect séquencement des tâches de traitement et de transport, pour lequel nous avons élaboré deux méthodes heuristiques (de type Tabou et basée sur une procédure de shifting bottleneck améliorée) ; puis en intégrant dans un deuxième temps la problématique de l’affectation induite par la flexibilité de certaines ressources. Pour cette dernière étape, nous avons combiné les méthodes précédentes avec un algorithme génétique. L’algorithme hybride obtenu nous permet de résoudre des instances de la littérature correspondant à divers cas spécifiques, avec des résultats assez proches des meilleures méthodes dédiées. A termes, il pourrait être intégré dans un système d'aide à la décision général qui s’affranchirait de la phase d’identification préalable du type de job shop considéré, et serait adapté à la résolution de nombreux cas (avec ou sans problème d'affectation, temps de traitement fixes ou bornés, avec ou sans stockage, etc..). / Our work focuses on an extension of the well known job shop scheduling problem. We call this extension the General Flexible Job Shop Scheduling Problem (GFJSSP). It occurs in various kinds of workshops which are particularly constrained by one or several transportation resources (called robots). GFJSSP is characterized by the flexibility of both machines and robots. In the studied problem, the term General involves unitary capacity transportation resources, bounded processing times, and possible input/output buffers for machines. After defining the workshop and the corresponding problem, we proposed two kinds of model for the GFJSSP: a mathematical model, and a graphical one. This last one is a generalization of the disjunctive graph commonly used for job shop problems. We then addressed the resolution in two steps: firstly, by focusing on the sequencing of processing and transportation tasks. For this purpose we have developed two heuristics (Tabu search and an improved shifting bottleneck procedure). Secondly, we have considered the assignment problem involved by the flexibility of some resources. For this last step, we combined the above methods with a genetic algorithm. This hybrid algorithm allowed us to solve various specific cases of instances in the literature, with performance rather close to the best dedicated methods. In the future, it could be integrated within a general decision support system which could emancipate from the initial identification phase of the considered type of job shop, and which would be suitable for solving many cases (with or without assignment problem, fixed or bounded processing times, with or without storage, and so on).
689

Recharge and residence times in an arid area aquifer

Müller, Thomas 02 August 2013 (has links) (PDF)
Deteriorating water quality in the face of a rising demand for agricultural products triggered interest in the groundwater resources of the Najd dessert, an arid region of southern Oman. Groundwater in this area usually is abstracted from one of the largest aquifers on the Arabian Peninsula, the Umm Er Radhuma aquifer. Increased discharge stands in contrast to limited precipitation: the monsoon is an annual event but it is regionally limited; cyclones infrequently occur within the range of three to seven years. Both are possible sources for groundwater recharge in the Najd. With these preconditions in mind, the present study investigates recharge to the Najd groundwaters as part of an active flow system and evaluates the mean residence time in the deep groundwaters. The tools of choice are a groundwater flow model combined with environmental isotope tracer data. The two-dimensional flow model replicates the characteristics of the aquifer system from the potential recharge area in the south (Dhofar Mountains) to the discharge area in the north (Sabkha Umm as Sammim). The south-to-north gradients and the observed artesian heads in the confined aquifer are reproduced. Simulation results indicate that changes between wet and dry periods caused transient responses in heads and head gradients lasting for several thousand years. Based on the used parameters the model calibration indicated, that a recharge rate of around 4 mm a−1 is sufficient to reproduce current groundwater levels. Since rising groundwater levels were documented after cyclone Keila in November 2011, modern recharge evidently occurs. 36-Cl concentrations and dissolved-helium concentrations indicate that the deep groundwaters in the central Najd are up to 550,000 years old. Thus, radiocarbon values indicating groundwater residence times for the central Najd up to 20,000 years and the northern Najd up to 35,000 years underestimate the groundwater residence times and seem to have been strongly affected by mixing during sampling. Decreasing 36-Cl and increasing 4-He concentrations confirm the expected trend in the direction of groundwater flow and prove to be more robust tracers for age dating of Najd groundwaters. Backward pathline tracking was used to simulate the groundwater ages. The tracking results show that a total porosity value between 15 and 20 % is consistent with the range of the observed chlorine-36 and heliumbased ages. The results and parameters obtained in the present study provide the basis for future 3D-groundwater models designed to evaluate the water resources available to the Najd’s agricultural complex. In addition, the developed 2D-model allows for studies of paleoclimate scenarios and their influence on the groundwater regime. / Ein steigender Bedarf nach landwirtschaftlichen Produkten - und damit Wasser - bei gleichzeitiger Abnahme des verfügbaren Wassers in Qualität und Menge in den bisherigen Anbaugebieten, führt zu einer intensiven Nutzung der Grundwasserressourcen der ariden Najd-Region in der Provinz Dhofar, im Süden des Sultanats Oman. Als Quelle dienen die Grundwasservorräte des Umm Er Radhuma-Aquifers, einer der Hauptaquifere auf der arabischen Halbinsel. Der steigenden Nutzung stehen mit dem jährlichen Monsoon, der regional limitiert ist, und unrgelmässigen, zwischen 3 und 7 Jahren auftretenden Unwettern (Zyklonniederschlag) nur begrenzte Niederschlagsmengen als Quellen für eine mögliche Zufuhr von Wasser (Grundwasserneubildung) zum Aquifersystem gegenüber. Der Ansatz der vorliegenden Arbeit besteht darin, mit Hilfe eines Grundwassermodells und der Einbeziehung von Umweltisotopen das tiefe und zur Nutzung geförderte Grundwasser in der Najd-Region als Teil eines aktiven Fließsystemes zu untersuchen und mittlere Verweilzeiten des Grundwassers abzuleiten. Ein 2D-Grundwassermodell entlang einer Fließlinie vom Dhofar Gebirge im Süden zur Sabkha Umm as Sammim im Nordosten wurde entwickelt. Das Modell reproduziert den Süd-Nord-Gradienten als auch den aufwärts gerichteten Gradienten mit höheren Grundwasserständen in den tiefen Grundwasserleitern. Die Simulationen zeigen, dass der Wechsel von ariden und humiden Phasen (wenig bzw. viel Grundwasserneubildung) zu Veränderungen der Grundwasseroberfläche führt die mehrere tausend Jahre anhalten können. Das kalibrierte Grundwassermodel zeigt, dass mit einer Neubildungsrate von 4 mm a−1 die natürlichen Grundwasserverhältnisse im Najd abgebildet werden können. Dass eine moderne Grundwasserneubildung stattfindet, konnte mittels Loggermessungen anhand steigender Grundwasserstände im tiefen Aquifersystem nach dem Extremunwetter im November 2011 (Zyklon Keila) eindeutig nachgewiesen werden. Die Analyse der 36Cl- und 4He-Konzentrationen zeigt, dass die tiefen Grundwasser im zentralen Najdgebiet bis 550 000 Jahren alt sein können. Das bedeutet allerdings, dass die über 14C Daten berechneten Grundwasseralter mit ca. 20 000 Jahren für das zentrale Najdgebiet und bis zu 35 000 Jahren für den nördlichen Najd, die Grundwasseralter deutlich unterschätzen. Die abnehmenden 36Cl und ansteigenden 4He Konzentrationen zeigen den erwarteten Trend in Grundwasserfließrichtung und können als aussagefähige Tracer für die Bewertung der Verweilzeiten und Alter des fossilen Grundwassers der Najd-Region angesehen werden. Mit Hilfe des Partickeltrackings wurden die Grundwasseralter, basierend auf den Isotopentracern, im Grundwassermodel simuliert. Die Porosität wurde dabei für das Aquifesystem mit Werten zwischen 15 und 20 % bestimmt. Die generierten Parameter und das gewonnene Systemverständnis sind eine wichtige Basis für zukünftige 3D-Modellstudien welche die Verfügbarkeit der Wasserresourcen im Najd untersuchen werden. Weitere Anwendungen für das in dieser Studie aufgebaute 2D-Modell sind Untersuchungen zum Paläoklima und dessen Einfluss auf das Grundwassersystem.
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Kartläggning av kapacitetsutnyttjandet och ställtider på Stålöv AB : Survey of the use of capacity and set up times at Stålöv AB

Nilsson, Marie, Hagström, Pernilla January 2006 (has links)
The aim of this report is to analyse the use of the capacity at the CNC (computer numerical control) cutters and show how the level of set up time for these cutters at Stålöv AB. This assignment is concrete whereas there are no subjective questions to this matter and there are only cold figures presented. Production economy is getting more important as the competition hardens and there are several different ways to increase productivity and efficiency in a company. In order to increase productivity and efficiency work studies are used to, through an analysis, find developments in methods that result in improved work methods and to establish the time that are used. Increased production of different parts and customer driven production in combination with increased demands on rationalisation of capital have led to an enlarged interest for shorter set up times in the production. To point out the use of capacity and the set up time of the cutters at Stålöv AB we used frequency studies. Frequency studies are work measure methods based on random observations on predetermined events to calculate the relative occurrence of these events. The purpose is to present the objective cold figures that show the use of capacity for all machines and totally. The compilation of the seven CNC cutters shows that the use of capacity reaches 33 %. The lack of machine operators is the single largest reason, 45 % of the total use of capacity. The set up time reaches 6 % totally of the 36 hours of observation of the machines. The study of the separate CNC cutters shows that the result follows the result of the compilation of all machines; the main reason why the use of capacity is low depends on the lack of machine operators. This means that if the demand increases there will not be enough operators to meet this demand. If using SMED, the set up time percentage share of the total use of capacity are too large, but the production of prototypes that supplies great value to the company may justify the set up times. By using Total Productive Maintenance (TPM), based on the elimination of breakdowns and defective products, the stability in production and the use of capacity may increase.

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