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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.
21

Capacity dimensioning of operations capacity in manufacturing companies

Sollander, Kristina, Hedvall, Lisa January 2016 (has links)
Purpose:To investigate how managers work with capacity dimensioning and what the main challenges are in order to balance efficiency and responsiveness in the continuous operations, as well as investigate what patterns and trends that can be identified within the capacity dimensioning approach. Methodology:A multiple case study was conducted including 14 manufacturing companies. Empirical data was collected through semi-structured interviews and used to explain the phenomenon of capacity dimensioning. Differences and similarities in the way companies approach capacity dimensioning was investigated though a cross-case analysis. The research is of exploratory and inductive character. Findings:A general process for capacity dimensioning has been established and affecting aspects and challenges has been identified. Potential trends and relationships have been investigated for the capacity dimensioning approach, with a potential connection between flexibility and investment strategy with introduction period in human resources. Further the capacity strategies tend to vary depending on alternative capacity sources. Theoretical implications:Information is provided for how capacity dimensioning is done at companies today, connections are strong to adjacent theories as S&OP but with more detail in the area of setting the capacity level. Managerial implications:The capacity dimensioning does not have a solution that suits all companies, but communication and alignment in the supply chain should not be underestimated for successful capacity dimensioning. Research delimitations:The research is conducted on manufacturing companies active in Sweden, other countries or continents of the world could generate other results because of different culture and laws. Further, service companies could also have provided other results.
22

Dimensioning and tolerancing in geometric modelling

余啓明, Yu, Kai-ming. January 1990 (has links)
published_or_final_version / Mechanical Engineering / Doctoral / Doctor of Philosophy
23

Modelling the logisitcs response to disasters / Outils et modèles pour l'organisation de réponses logistiques face aux situations de crise sanitaires

Chen, Wanying 27 May 2015 (has links)
Cette thèse est consacrée à l'optimisation de la logistique sanitaire pour soutenir les plans de gestion de crise afin de réduire les effets des catastrophes naturelles et/ou humaines en termes de santé publique. Les catastrophes naturelles peuvent être prédites, mais elles sont difficiles à éviter. Par conséquence, la prise en charge des victimes potentielles et le dimensionnement des moyens logistiques de secours y afférent sont d'une importance cruciale. Une approche analytique en trois étapes est proposée afin d'étudier le dimensionnement des ressources et l'organisation des plans de gestion de crise (plan blanc) d’origine naturelle. La première étape propose un modèle de référence pour concevoir un plan de gestion de crise. La deuxième étape considère un modèle d’optimisation linéaire pour prédire le nombre de ressources nécessaires. La dernière étape présente un modèle dynamique pour simuler l'ensemble de l’organisation de manière fine. L'évacuation d’un hôpital dans le cadre d’un plan blanc étendu à plusieurs hôpitaux pour faire face à un tsunami fluvial a été considérée comme scénario pour évaluer la justesse de notre approche. Les catastrophes d'origine humaine et la propagation des maladies peuvent donner lieu à des désastres de grande ampleur qui mobilisent de nombreuses ressources humaines et matérielles. Par exemple, un modèle de réponse logistique face à une attaque bioterroriste avec un agent non-contagieux ainsi qu’un modèle pour la réponse logistique aux épidémies ont été proposés. Elles traduisent un problème de gestion d’inventaire multi-échelons et multi-périodes. Ces deux modèles dynamiques de flux requièrent une optimisation linéaire et une optimisation non-linéaire respectivement. Ils intègrent les caractéristiques de la gestion de ces catastrophes: la propagation de l’infection ou de la maladie, les réponses médicales appropriées et le déploiement de la logistique associée. Avec ces deux modèles, le nombre de patients aux différents stades de la maladie et le nombre des ressources médicales nécessaires pour chaque période peuvent être calculés. Les facteurs qui influent sur le nombre de décès et l’efficience des différentes politiques d'intervention médicale, peuvent également être évalués. Les deux modèles peuvent ainsi aider les décideurs à prévoir les conséquences de la situation en cas de catastrophe ainsi que de connaître les informations d'une réponse pertinente, ceci à un niveau stratégique. Une réponse logistique à une attaque bioterroriste anonyme à l'anthrax dans un centre commercial et une réponse logistique à une pandémie H5N1 sont pris comme scénarios pour tester l'efficacité des modèles correspondants. / This thesis is devoted to optimize the health care logistics which can support emergency management plans to reduce the impacts of natural and/or man-made disasters. After the review of relevant papers, two main gaps have been found in the current studies. One is that most of the researches are not based on real cases. The other is that some main characteristics of disasters are neglected when disasters are studied. Therefore, based on real case scenarios, the thesis studies different disasters (natural and/or man-made disasters) separately according to the characteristics of disasters. Natural disasters may be predicted but are difficult to avoid. Therefore, the evacuation of potential victims and the dimensioning of relief resources are crucially important. A three-step approach is proposed to study the resource dimensioning and the organization of emergency management plan (French White Plan) facing natural disasters. In our three-step approach, the first step builds a framework model to get the insights of emergency management plan clearly. The second step establishes a global model (a linear model) to predict the quantity of required resources for evacuation. The third step proposes a detailed simulation model to reflect the real world more precisely. The hospital evacuation under the guidance of a French Extended White Plan in case of a flood has been taken as a real case scenario to test the correctness of our approach. The man-made disasters and the outbreak of diseases can be large-scale disasters which require a high demand of resources. In this thesis, a model for logistics response to bioterrorist attack with a non-contagious agent and another model for the logistics response to epidemics have been proposed. Multi-period and multi-echelon inventory management problems have been studied. The two models (a linear model and a non linear model respectively) combine the main characteristics of disasters: the propagation of the disease, the relevant medical interventions and the logistics deployment together. The number of patients in different disease stages and the required medical resources for each period can be estimated. The factors affecting the number of deaths and the different medical intervention policies can also be evaluated with the two models. With the help of the models, the decision makers can get an idea of the disaster situation and the relevant medical responses from a strategy level. A logistics response to an anonymous bioterrorist attack with anthrax to a shopping center and the logistics response to the outbreak of H5N1 are taken as real case scenarios to test the effectiveness of the models respectively.
24

Dimensionamento de profissionais de enfermagem em ambulatório de oncologia e hematologia / Dimensioning of nursing professionals at an oncology and hematology outpatient unit

Martin, Lelia Gonçalves Rocha 22 November 2013 (has links)
Introdução: Os ambulatórios de oncologia vêm atendendo, a cada dia, um número crescente de pacientes que necessitam de cuidados clínicos complexos; todavia, boa parte desses serviços não possui informações que possam dar suporte às decisões relativas ao dimensionamento de profissionais de enfermagem. Objetivos: Identificar e analisar as intervenções / atividades realizadas pelos profissionais de enfermagem e definir parâmetros para dimensionar o quadro de pessoal de enfermagem em ambulatório especializado em oncologia e hematologia. Método: Pesquisa metodológica de campo que utiliza a técnica de amostragem de trabalho realizada em um ambulatório de oncologia e hematologia de uma organização de saúde privada localizada na cidade de São Paulo. Os dados foram coletados de 15 a 19 de abril de 2013 e foram organizados nas etapas seguintes: (1) Construção do instrumento de medida da frequência e do tempo despendido em intervenções de enfermagem; (2) Validação das intervenções / atividades do instrumento; (3) Identificação da frequência e do tempo despendido pelos profissionais de enfermagem em intervenções / atividades; (4) Dimensionamento de profissionais de enfermagem em ambulatório de oncologia e hematologia. Resultados: O instrumento construído e validado englobou 34 intervenções e três atividades. Foram registradas pelos observadores de campo 3694 observações dos profissionais de cada categoria na execução das intervenções / atividades de enfermagem. A documentação foi a intervenção que despendeu maior tempo da equipe (24,1%). Seguida desta, as intervenções que mais interferiram na carga de trabalho dos enfermeiros foram: Manutenção de dispositivos de acesso venoso (9,2%), Controle da quimioterapia (7,9%), Acompanhamento por telefone (5,1%) e Presença (4,7%); e, para os técnicos de enfermagem: Controle do ambiente em conforto (12,3%), Punção de vaso para amostra de sangue venoso (11,9%), Presença (10,1%) e Monitorização de Sinais Vitais (9,4%). A média diária dos pacientes correspondeu a 37,2 (±4,4) pacientes. O tempo médio de cuidado por paciente relativo aos cuidados de enfermagem, atividades associadas, tempo de espera e atividades pessoais correspondeu a 3,3h (80% de enfermeiros e 20% de técnicos de enfermagem). A produtividade encontrada foi de 81,3%. Conclusão: Este estudo possibilitou indicar parâmetros para o dimensionamento, bem como identificar o tipo e a proporção das intervenções de enfermagem que interferem na carga de trabalho e aplicar equações para o cálculo de profissionais de enfermagem. Entretanto, ainda constitui-se em uma visão restrita da realidade, necessitando ser replicado em vários e diferentes ambulatórios especializados em oncologia / Introduction: Oncology outpatient units have been receiving an increasing number of patients who need complex clinical care; however, most of them do not have appropriate information to support nursing staffing decisions. Objectives: To identify and analyze interventions/ activities performed by nursing professionals and to define parameters used to determine nursing staffing in a specialized oncology and hematology outpatient centers. Methods: Field methodology study that uses sampling technique, carried out in an oncology and hematology outpatient center of a private healthcare organization located in the city of Sao Paulo. Data were collected between April 15 to 19, 2013 and organized into steps: (1) Design a tool to measure frequency and duration of nursing interventions; (2) Validation of interventions/ activities of the tool; (3) Identification of frequency and time spend by nursing professionals in their interventions/ activities; (4) Dimensioning of nurses in an oncology and hematology outpatient unit. Results: The tool was designed and validated and encompassed 34 interventions and three activities. The field observers documented 3,694 observations of professionals in each category of nursing interventions/ activities. Documenting (24.1%) was the intervention that required more time from the team. Next, the activities that required more time from the nursing team were: maintenance of devices: venous access (9.2%), chemotherapy control (7.9%), telephone follow-up (5.1%) and person-to-person follow-up (4.7%). To nursing technicians, the activities were: environment control - comfort (12.3%); venous puncture - venous blood sample (11.9%); presence (10.1%), and monitoring of vital signs (9.4%). The mean daily number of patients corresponded to 37.2 (±4.4) patients. The average time spent on patient care, related to nursing care, associated activities, waiting time and personal activities corresponded to 3.3 hours (80% of nurses and 20% of nursing technicians). Productivity was 81.3%. Conclusion: This study led to the definition of parameters for staffing, plus the identification of type and proportion of nursing interventions that interfered on the workload and the application of equations to calculate nursing staffing. However, it still is a restricted view of the reality, which has to be multiplied in several and different specialized oncology outpatient centers.
25

Tempo de assistência de enfermagem: identificação e análise em instituição hospitalar de ensino. / Time of nursing care: identification and analisys of a teaching hospital.

Rogenski, Karin Emilia 06 September 2006 (has links)
Estudo de abordagem quantitativa, elaborado com o objetivo de identificar e analisar o comportamento do tempo médio de assistência de enfermagem despensado aos pacientes, das Unidades de Internação do HU-USP, no período de 2001 a 2005. A identificação das variáveis intervenientes no cálculo do tempo médio de assistência de enfermagem, possibilitou a aproximação com a realidade das Unidades, permitindo visualizar a distribuição dos leitos, a quantidade média diária de pacientes assistidos, a quantidade média de pessoal existente nas Unidades de Internação e o Índice de Segurança Técnica, segundo as categorias profissionais. Verificou-se que o número e a distribuição de leitos das Unidades sofreu alterações ao longo do período analisado. O percentual de ausência prevista sofreu variação entre os índices encontrados em cada Unidade, evidenciando que, as ausências previstas por folga mostraram-se superiores ao indicados pela literatura, apontando para a possibilidade da Instituição conceder um número maior de feriados do que aqueles estabelecidos pelas leis e decretos federais, estaduais e municipais, como por exemplo, as emendas de feriados. Com relação as ausências não previstas, verificou-se que as faltas, as licenças médicas e as licenças maternidade constituíram os tipos mais constantes de ausências, no entanto, constatou-se que o percentual de ausência não prevista por licença INSS foi bastante significativo na categoria técnico/auxiliar de enfermagem. O tempo médio de assistência de enfermagem, apesar de algumas variações, manteve-se equilibrado durante todo o período para a maioria das Unidades, com exceção das Unidades de UTIP e BER que sofreram diminuição do tempo de assistência de enfermagem nos anos de 2003 e 2004, respectivamente. Constatou-se, ainda, que o tempo médio de assistência identificado, na maioria das Unidades de Internação, apresentou variações conforme as alterações observadas no quantitativo médio de pessoal de enfermagem e no número médio de pacientes. Os resultados apontados, referentes a distribuição percentual do tempo de assistência entre os profissionais da equipe de enfermagem, corroboram os encontrados em outros estudos, que já demonstraram que a proporção de horas atribuídas às enfermeiras, são inferiores aquelas atribuídas aos técnicos e auxiliares de enfermagem, e estão muito distantes daquilo que é preconizado pelo COFEN. O desenvolvimento desse estudo evidencia perspectivas para a realização de outras pesquisas que complementem as análises realizadas e verticalizem o conhecimento das variáveis que interferem no processo de identificação do tempo médio de assistência despensado aos pacientes das instituições hospitalares. / Study of quantitative approach, created for aiming to identify and analyze the average time behavior of nursing care delivered for the patients from the Internment Units at HU-USP from 2001 to 2005. The identification of intervenient variables in the average time calculus of nursing care made it possible the contact with the reality in the Units, allowing us to visualize the bed distribution, daily average amount of attended patients, the average amount of personnel working in the Internment Units and the Technical Safety Index, according to professional categories. It was verified that the number and distribution of beds in the Units had changes throughout the analyzed period. The percentage of predicted absence had variations among the indexes found in each Unit, proving that predicted absences for days off were higher than the ones seen in literature, pointing to the possibility of the facility to concede a greater number of holidays than those established by laws and local, state and federal decrees, as for example, the holiday bridges. Regarding to the unpredicted absences, it was verified that the missing days, medical leaves and maternity leaves were the most constant kinds of absence. However, it was noticed that the percentage of unpredicted absence for INSS leaves was quite high in the nursing technician/auxiliary categories. Average time of nursing care, despite of some variations, kept stable throughout the period in most Units, except for UTIP and BER Units, which suffered a reduction of nursing care time in the years of 2003 and 2004 respectively. It was also evidenced that the average time of care identified in most Internment Units presented variations as the observed changes in the average amount of nursing staff and the average number of patients. The results obtained, referring to the percentage of distribution of time for care among the nursing staff professionals confirm the ones found in other studies, which showed that the proportion of hours attributed to nurses are lower than those attributed to nursing technicians and auxiliaries, which are very far from what is advised by COFEN. The development of this study shows perspectives for making other researches that complement the analyses made to deepen the knowledge of the variables that interfere in the process of identification of the average time devoted for caring the patients in the hospital institutions.
26

"Dimensionamento de pessoal de enfermagem no Hospital Universitário do Oeste do Paraná" / Dimensioning of Nursing Personnel in the University Hospital of Western Paraná.

Nicola, Anair Lazzari 15 February 2005 (has links)
O papel desempenhado pelos recursos humanos na produção de serviços de saúde e, particularmente, no campo da enfermagem merece atenção especial. Este estudo aborda a temática da gerência de recursos humanos tomando por referência a questão do dimensionamento de pessoal de enfermagem em um setor específico de atuação: o hospital. Trata-se de uma investigação na modalidade de estudo de caso cujo objetivo geral é dimensionar o quadro de pessoal de enfermagem para unidades de internação de um hospital universitário situado em um município do oeste do estado do Paraná. A metodologia adotada é aquela proposta por Gaidzinski (1998) que contempla a identificação de determinadas variáveis, às quais correspondem instrumentos específicos de coleta de dados. Para identificação do grau de dependência do paciente em relação ao cuidado de enfermagem, utilizou-se o Sistema de Classificação de Pacientes segundo Perroca (2000); para as horas médias de assistência de enfermagem e o percentual de cada categoria profissional adotou-se como parâmetro a Resolução COFEN nº 189/96; a definição do índice de absenteísmo bem como a equação para cálculo do quadro de pessoal foram desenvolvidas segundo a metodologia preconizada por Gaidzinski (1998). As unidades de internação estudadas foram aquelas em que a clientela atendida era composta por adultos (≥ 14 anos), nas especialidades de clínica médica e clínica cirúrgica. Do total de 62 leitos ativados nas três unidades de internação estudadas, foram classificados, diariamente durante 92 dias consecutivos, 72,5% dos leitos que correspondem a 4.135 pacientes/dia. Para os demais 27,5% dos leitos, a classificação não se efetivou devido à recusa do paciente em participar do estudo e outras ocorrências. Dos pacientes classificados, 9,4% requeriam cuidados intensivos, 14,6% cuidados semi-intensivos, 45,1% cuidados intermediários e 30,9% cuidados mínimos. Para as ausências previstas, o maior índice deve-se às folgas semanais, para as ausências não previstas o índice mais elevado ocorre devido às licenças médicas. Aplicando-se a equação de dimensionamento, obteve-se um quadro projetado de 28 enfermeiros e 48 auxiliares de enfermagem. Comparando-se o quadro existente com o projetado verifica-se que para a categoria enfermeiro, o quantitativo existente corresponde a 50% daquele previsto; para a categoria de auxiliares de enfermagem há um excedente de 29,2%. Diante do quadro reduzido de enfermeiros, levanta-se a hipótese de que determinadas ações de enfermagem inerentes a esse profissional estejam sendo desenvolvidas pelo pessoal de nível médio, sem um processo de supervisão que permita o desenvolvimento de um trabalho mais articulado e integrativo, resultando em uma assistência de enfermagem de melhor qualidade. Entende-se, ainda, que a adoção, pelos enfermeiros, de um sistema de classificação de pacientes em suas respectivas unidades, permitirá ampliar o conhecimento acerca da clientela atendida, suas reais necessidades, bem como o desenvolvimento de habilidades e competências que lhe assegurem assistir e gerenciar de um modo mais seguro, inovador, autônomo e participativo. / and particularly in the Nursing field, deserves special attention. This study approaches human resources management based on the dimensioning of nursing personnel in a specific sector of activity: the hospital. It is a case study whose goal is to dimension the nursing personnel for inpatient units at a university hospital located in a city of western Paraná state. The methodology adopted is that proposed by Gaidzinski (1998), as it contemplates the identification of certain variables to which specific data collection instruments correspond. In order to identify patients’ dependence in relation to nursing care, the Patient Classification System was used according to Perroca (2000); concerning the mean hours of nursing care and the percentage of each professional category, Resolution COFEN no. 189/96 was adopted as a parameter; the definition of absence rates as well as the equation used to calculate the staff were developed according to the methodology proposed by Gaidzinski (1998). The inpatient units under study were those in which the clients assisted consisted of adults (≥ 14 years old) in the specialties of medical clinic and surgical clinic. Of the total number of 62 activated beds in the three inpatient units under study, 72.5% of the beds were classified daily during a period of 92 consecutive days, which corresponds to 4.135 patients/day. As to the remaining 27.5% beds, classification was not conducted due to patients’ refusal to participate in the study and to other occurrences. Of the classified patients, 9.4% required intensive care, 14.6% semi-intensive care, 45.1% intermediate care and 30.9% minimum care. Concerning predicted absences, the highest rate was due to weekly work pauses whereas for non-predicted absences, the highest rate occurred as a result of sick leaves. The application of the dimensioning equation resulted in a staff consisting of 28 nurses and 48 nursing auxiliaries. By comparing the existing staff and the projected staff, it was observed that the number of working nurses corresponded to 50% of the predicted number whereas, in relation to nursing auxiliaries, there was an excess of 29.2%. In view of the reduced number of nurses, a hypothesis was made that certain nursing actions which are inherent to that professional category are being performed by nursing auxiliaries without a supervision process that would allow for the development of more articulated and integrative work, which would, in turn, result in better quality nursing care. It is also understood that the adoption, by nurses, of a patient classification system in their respective units will bring further knowledge concerning the clients assisted, their real needs as well as the development of skills and competencies that will enable them to provide care and manage their work in a more safe, innovative, autonomous and participant fashion.
27

Método para planejamento de capacidade de redes ATM baseado em simulação / Capacity planning method for atm networks based on simulation

Goncalves, Adriano Ramos January 2001 (has links)
O processo de dimensionar redes de comunicação tem sido um desafio para pesquisadores e projetistas. A partir da especificação, passando pela operação, controle e gerenciamento de redes, as estimativas de comportamento do desempenho são úteis para o dimensionamento adequado dos equipamentos. O detalhamento e precisão na capacidade de avaliar o impacto de carga futura melhoram as chances de prever dificuldades em atingir metas de serviços. Com redes de banda larga, como ATM, não tem sido diferente. Pela sua concepção de oferecer garantia de qualidade para serviços com diferentes requisitos, ATM se empenha em evitar a sobrecarga da rede. De início, essa premissa é preservada naturalmente através da restrição da quantidade e tipo de conexões ingressas na rede. Portanto, a adequação dos recursos que compõem a estrutura de uma rede ATM determina o grau de disponibilidade em atender certa quantidade de serviços. A pergunta que desejamos responder é: como estimar com precisão a quantidade de serviço suportada por determinada rede ATM? O limite da rede é alcançado quando os recursos disponíveis são menores que os recursos necessários à carga de serviço. Com o emprego cada vez maior de ATM por empresas de telecomunicações, conhecer o limite da rede é estar ciente da potencialidade de negócios sem comprometimento da qualidade. É poder prever expansões evitando bloqueio de novos serviços. O processo de dimensionamento de capacidade de uma rede ATM revela a quantidade de recursos necessários para suportar determinada carga de serviço. Quando os recursos necessários forem maiores que os recursos disponíveis, o limite da rede foi alcançado. Nesse caso, são duas as possibilidades para o equilíbrio: aumentar os recursos da rede ou diminuir a carga de serviço desejado. Esta dissertação propõe um método para dimensionamento dos recursos de uma rede ATM. A principal técnica empregada no método é a simulação do comportamento de tráfego sobre comutadores ATM. Para determinada carga de tráfego são executadas diferentes simulações variando os recursos disponíveis dentro de parâmetros prováveis. As seguintes medidas de desempenho são obtidas nas simulações como resultados estatísticos médios: razão de perda de células (CLR), atraso de transferência de células (CTD) e variação do atraso de células (CDV). Conhecendo o desempenho desejado (QoS) pela carga de serviço, o método pode determinar a quantidade necessária de recursos que satisfazem os requisitos de QoS. A ferramenta escolhida para implementar o modelo foi o simulador orientado a eventos ATM/HFC do National Institute of Standards and Technology (NIST). O simulador é composto por diferentes modelos de elementos, cada qual com seus atributos, que podem ser combinados para caracterizar determinadas configurações de rede que se deseja avaliar. Os elementos podem ser desde representações de tipos de comutadores ATM até diferentes técnicas de controle de tráfego a serem utilizadas na simulação. A carga de serviço na simulação é provida por elementos modeladores que caracterizam diferentes tipos de aplicações geradoras de tráfego, permitindo arranjos de serviços CBR, VBR, ABR e UBR através de seus respectivos parâmetros descritores. A validação do método é efetuada através da comparação dos resultados obtidos com outro trabalho similar desenvolvido utilizando simulação. / The process of planning communication networks has been a challenge for researchers and designers. From the specification, through the operation, control and management of networks, the behavior performance estimates are useful for the adequate equipment dimensioning. The detailing and accuracy in the capacity to evaluate the future load impact increase the possibilities to forecast difficulties in reaching goals of services. With broadband networks, as ATM, it has not been different. ATM efforts in preventing network overload by its conception to offer quality guarantee for services with different requirements. From beginning, this premise is naturally preserved through restriction of the amount and type of connections that can enter the network. Therefore, the adequacy of the resources that compose the ATM network structure determines the degree of availability in attending certain amount of services. The question that we wish to answer is: how can we estimate accurately the amount of services supported by specific ATM network? The limit of the network is reached when the available resources are below the necessary resources to service load. With the higher use of ATM for telecommunications companies, to know the limit of network is to be aware of the potentiality without damage to the quality. It's to be able to forecast expansions to prevent new services blocking. The capacity planning process of an ATM network shows the amount of resources needed to support a specific workload. When the resource need is greater than the available resource, the network limit has been reached. In this case, there are two possibilities to reach balance: increase the network resources or lower the load of desired service. This work is about a method for ATM network resources dimensioning. The main technique used in the method is the traffic behavior simulation over ATM switches. For specific workload, different simulations are executed and they vary according to the resources available inside the probable parameters. The following measures of performance are gotten in the simulations as average statistics results: cell loss ratio (CLR), cell transfer delay (CTD) and cell delay variation (CDV). Knowing the workload desired performance (QoS), the method can determine the necessary amount of resources that will satisfy the QoS requirements. The chosen tool to implement the model was the event driven simulator ATM/HFC of the National Institute of Standards and Technology (NIST). The simulator is made up of different models of elements, each one with its attributes, which can be combined to characterize specific network configurations that are to be evaluated. The elements can range from representations of types of ATM switches to different techniques of traffic management to be used in the simulation. The workload in the simulation is provided by modeler elements that characterize different types of traffic generator applications, allowing sets of CBR, VBR, ABR and UBR services through their respective traffic parameters. The method validation is carried out through the matching of the results gotten with other similar work developed using simulation.
28

Optimisation du processus du contrôle métrologique des pièces mécaniques dans le cadre d’une analyse 3D du tolérancement / Optimization of metrological control of mechanical parts process in a 3D analysis of tolerancing

Tran, Dinh Tin 12 September 2014 (has links)
Dans le cadre de la conception et de la fabrication des produits industriels, on retrouve principalement les étapes de conception, fabrication et contrôle. Le concepteur défini un tolérancement fonctionnel des pièces en lien étroit avec les procédés de fabrication. L’étape du contrôle des pièces est alors l’étape primordiale permettant la validation du produit fabriqué vis-à-vis des besoins du concepteur. Le sujet de recherche se place dans une optique d’optimisation du processus de contrôle des pièces. Cette étude d’optimisation du processus de contrôle devra se faire à plusieurs niveaux : - Au niveau des coûts liés à l’opération de mesure : lorsqu’un opérateur définit sa gamme de contrôle, il valide si possible l’ensemble de la pièce sur un unique moyen de mesure, même si le moyen de mesure choisi n’est pas le plus adapté. Cette partie de l’étude concerne les concepts de capabilité des moyens de mesures, tant matériels que logiciels. Elle permettra de définir les limites de chaque appareil. L’analyse poussée de l’adéquation entre le tolérancement et les matériels de mesure permet également au contrôleur de définir une stratégie économique de mesure (temps, matériel, …). - Au niveau des innovations techniques à prendre en compte : l’utilisation couplée d’un logiciel de calcul par éléments finis : Abaqus (permettant de modéliser les déformations des pièces lors de leur conformation sur le montage de contrôle), et d’un logiciel de traitement du tolérancement : 3DCS (permettant de valider les effets des dispersions des moyens de contrôle sur le résultat de la mesure : incertitude de mesure). / As part of the design and manufacturing of industrial products, we mainly find the steps of design, manufacture and control. The designer choose functional tolerancing values and specification for a part closely with manufacturing processes. The step of the control of parts is then an essential stage of the validation of the product made with respect to the needs of the designer. The research subject is placed in order to optimize process control parts. This optimization should be done at several levels: - In terms of costs to the measurement process: when an operator sets its control methodology, he validates if possible the entire piece on a unique way to measure it, even if the measurement device selected is not the most appropriate. This part of the study concerns the concepts of capability of measuring devices and calculation methods. It will define the limits of each machine. The analysis of the adequacy between the tolerancing specifications and the measurement tools also allows the controller to define a strategy for economic measurement (time, equipment, ...). - In terms of technical innovations to be taken into account: we will use simultaneously a finite element software, (Abaqus, for modeling the deformations of parts during the control process) and a software for tolerances analysis, (3DCS, to validate the effects of the dispersions of the measurement device over the validity of the result of the measure : measurement uncertainty).
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Dimensionering av bärverk av stål : En jämförelse mellan Eurokod och BKR / Dimensioning of structures of steel : a comparison between the Eurocode and the BKR

Lengstrand, Anders January 2011 (has links)
The design regulations of Boverket (BKR) have long been the mandatory standard for construction design in Sweden. However from the end of the year 2010, the BKR will be replaced by the European standard Eurocode (EC). The transition to EC has been delayed and it is not until the second of May 2011 that the use of EC will be mandatory. Because EC and BKR differ from each other it is highly interesting to investigate and explain these differences. The purpose of the thesis is to compare the two standards and investigate how they give different results or not for the dimensioning of structures of steel with associated loads. The current project HVC (Pets Science Center) in Uppsala is used as a model for the design of the steel structure used in this study. The investigation is divided into two parts: the calculation of loads and the dimensioning of the steel structure. The internal forces in the construction that are used for the dimensioning are calculated with finite element programs (FEM-programs). The calculations for the comparison of the dimensioning of the steel structure are thereafter calculated by hand according to the current standard of each. Eurocode 3 (EC 3) is the current standard for EC and for BKR the current standard is the handbook for steel structures (BSK 07). The compared parts are: •the control of flexural buckling of a framework brace towards compression force and bending, •the control of a framework brace towards tension force and bending, •the control of a column against compression by a pure normal force, •and the control of a welded joint between a framework brace and an underlying beam. The results from the dimensioning are presented separately in the report and show that in almost all cases of design a lower grade of utilization is obtained for EC 3 than BSK 07. The largest obtained difference is when the dimensioning of a framework brace towards compression force and bending is made there the relationship between the utilization rates are 0,80. The results show that dimensioning according to EC 3 probably will lead to decreased costs within the construction sector, mainly in materials because smaller dimensions are required.
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Jämförelse Mellan Lätt och Tung Stomme på ett Kontorshus / Comparison between Light and Heavy Frame of an Office Building

Aljija, Elnes January 2012 (has links)
I början av varje nytt projekt stöter man på de olika alternativ av stomme- och bjälklagskonstruktioner som finns att välja mellan, och frågan blir ofta vilken alternativ som är optimal för den aktuella projekteten. Den optimala lösningen för varje projekt existerar inte, på grund av de olika faktorer och förutsättningar som styr projektet, till exempel: ekonomi, typ av byggnad, terrängtyp etc. Frågeställningen i denna rapport är om limträ eller betong är den mest optimala alternativen som stommaterial i det aktuella projektet. Jämförelsearbetet utgående från förutsättningar har gjorts genom att dimensionera delar av ett projekt med både materialen. Fokus har lagts på skillnader i byggnadshöjd, vindstabilitet och grundläggningen. Resultaten tyder på om man ska bygga ett kontorshus eller flervåningshus vore betong mer lämpligare alternativ jämfört med limträ. Skillnaden i byggnadshöjd finns men är förvånansvärt inte så stor mellan de två olika stommaterial. Dock skillnaden varierar avsevärd när det gäller bjälklagshöjd mellan limträ och betong. Detta pga krav på nedböjning och svikt som ställs på limträbjälklag. Båda stommaterial klara vindstabiliteten utan plintar, som är ganska intressant speciellt med tanke på limträets låga vikt. När det gäller grundläggningen, blev skillnaden betydlig större mellan limträ och betong. Dimensionering enligt Eurokoder har gjorts genom egna handberäkningar och även användandet av programvaran Strusoft. / At the beginning of each new project comes across on the different options of frame and floor construction available to choose from, and the question is often which option that is optimal for the current project. The optimal solution for each project does not exist, because of the different factors and conditions that govern the project, such as: economy, building type, terrain type, etc. The issue addressed in this report is on glue-laminated wood or concrete is the most ideal alternative to framing materials in the current project. Comparative work on the basis of preconditions has been made by dimensioning the parts of a project with both materials. The focus was on differences in building height, wind stability and the foundation. The results indicate if you're going to build an office building or apartment building,concrete is more appropriate alternative compared to the glue-laminated wood. The difference in building height is surprisingly not so great between the two different frames. However, the difference varies considerably in terms of floor height between glue-laminated wood and concrete. This is due to requirements for deflection and springines imposed on wood. Both frames can handle wind stability without plinths, which is quite interesting especially in view of the wood's light weight. Regarding the foundation, the difference was significantly greater between glue-laminated wood and concrete. The design according to Eurocodes has been made by hand calculations and also the use of the software Strusofts.

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