1000 resultados para Terminals (Informàtica)
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Em virtude da necessidade de inovação das empresas, gerada pelas transformações tecnológicas e pela velocidade da globalização, uma tendência mundial começa a surgir: o enfraquecimento de mão de obra no setor industrial e um considerável aumento no setor de serviços. Essa realidade pressupõe a criação de várias empresas, na sua maioria, de pequeno porte, o que dá especial importância a esse estudo, pois aliado à criação de novas empresas, o seu índice de mortalidade extremamente alto indica um problema a ser investigado. Portanto, a presente pesquisa procura sugerir estratégias de marketing eficientes como fatores amenizadores desse problema, e um caminho possível para a manutenção e o desenvolvimento das pequenas empresas. Criou-se, então, um modelo para a aplicação de estratégias de marketing, específico para empresas de pequeno porte. O modelo desenvolvido neste trabalho parte de uma revisão crítica da bibliografia referente às peculiaridades das pequenas empresas, como também das práticas de marketing, e busca correlacioná -las, através de uma pesquisa descritiva no formato de estudo de caso e determinando quais as condições para o uso do marketing nas pequenas empresas, quais as estratégias compatíveis e quais as mudanças necessárias à sua prática.
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There is a growing demand for data transmission over digital networks involving mobile terminals. An important class of data required for transmission over mobile terminals is image information such as street maps, floor plans and identikit images. This sort of transmission is of particular interest to the service industries such as the Police force, Fire brigade, medical services and other services. These services cannot be applied directly to mobile terminals because of the limited capacity of the mobile channels and the transmission errors caused by the multipath (Rayleigh) fading. In this research, transmission of line diagram images such as floor plans and street maps, over digital networks involving mobile terminals at transmission rates of 2400 bits/s and 4800 bits/s have been studied. A low bit-rate source encoding technique using geometric codes is found to be suitable to represent line diagram images. In geometric encoding, the amount of data required to represent or store the line diagram images is proportional to the image detail. Thus a simple line diagram image would require a small amount of data. To study the effect of transmission errors due to mobile channels on the transmitted images, error sources (error files), which represent mobile channels under different conditions, have been produced using channel modelling techniques. Satisfactory models of the mobile channel have been obtained when compared to the field test measurements. Subjective performance tests have been carried out to evaluate the quality and usefulness of the received line diagram images under various mobile channel conditions. The effect of mobile transmission errors on the quality of the received images has been determined. To improve the quality of the received images under various mobile channel conditions, forward error correcting codes (FEC) with interleaving and automatic repeat request (ARQ) schemes have been proposed. The performance of the error control codes have been evaluated under various mobile channel conditions. It has been shown that a FEC code with interleaving can be used effectively to improve the quality of the received images under normal and severe mobile channel conditions. Under normal channel conditions, similar results have been obtained when using ARQ schemes. However, under severe mobile channel conditions, the FEC code with interleaving shows better performance.
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The use of digital communication systems is increasing very rapidly. This is due to lower system implementation cost compared to analogue transmission and at the same time, the ease with which several types of data sources (data, digitised speech and video, etc.) can be mixed. The emergence of packet broadcast techniques as an efficient type of multiplexing, especially with the use of contention random multiple access protocols, has led to a wide-spread application of these distributed access protocols in local area networks (LANs) and a further extension of them to radio and mobile radio communication applications. In this research, a proposal for a modified version of the distributed access contention protocol which uses the packet broadcast switching technique has been achieved. The carrier sense multiple access with collision avoidance (CSMA/CA) is found to be the most appropriate protocol which has the ability to satisfy equally the operational requirements for local area networks as well as for radio and mobile radio applications. The suggested version of the protocol is designed in a way in which all desirable features of its precedents is maintained. However, all the shortcomings are eliminated and additional features have been added to strengthen its ability to work with radio and mobile radio channels. Operational performance evaluation of the protocol has been carried out for the two types of non-persistent and slotted non-persistent, through mathematical and simulation modelling of the protocol. The results obtained from the two modelling procedures validate the accuracy of both methods, which compares favourably with its precedent protocol CSMA/CD (with collision detection). A further extension of the protocol operation has been suggested to operate with multichannel systems. Two multichannel systems based on the CSMA/CA protocol for medium access are therefore proposed. These are; the dynamic multichannel system, which is based on two types of channel selection, the random choice (RC) and the idle choice (IC), and the sequential multichannel system. The latter has been proposed in order to supress the effect of the hidden terminal, which always represents a major problem with the usage of the contention random multiple access protocols with radio and mobile radio channels. Verification of their operation performance evaluation has been carried out using mathematical modelling for the dynamic system. However, simulation modelling has been chosen for the sequential system. Both systems are found to improve system operation and fault tolerance when compared to single channel operation.
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The proliferation of visual display terminals (VDTs) in offices is an international phenomenon. Numerous studies have investigated the health implications which can be categorised into visual problems, symptoms of musculo-skelctal discomfort, or psychosocial effects. The psychosocial effects are broader and there is mixed evidence in this area. The inconsistent results from the studies of VDT work so far undertaken may reflect several methodological shortcomings. In an attempt to overcome these deficiencies and to broaden the model of inter-relationships a model was developed to investigate their interactions and Ihc outputs of job satisfaction, stress and ill health. The study was a two-stage, long-term investigation with measures taken before the VDTs were introduced and the same measures taken 12 months after the 'go-live' date. The research was conducted in four offices of the Department of Social Security. The data were analysed for each individual site and in addition the total data were used in a path analysis model. Significant positive relationships were found at the pre-implementation stage between the musculo-skeletal discomfort, psychosomatic ailments, visual complaints and stress. Job satisfaction was negatively related to visual complaints and musculo-skeletal discomfort. Direct paths were found for age and job level with variety found in the job and age with job satisfaction and a negative relationship with the office environment. The only job characteristic which had a direct path to stress was 'dealing with others'. Similar inter-relationships were found in the post-implementation data. However, in addition attributes of the computer system, such as screen brightness and glare, were related positively with stress and negatively with job satisfaction. The comparison of the data at the two stages found that there had been no significant changes in the users' perceptions of their job characteristics and job satisfaction but there was a small and significant reduction in the stress measure.
A simulation analysis of spoke-terminals operating in LTL Hub-and-Spoke freight distribution systems
Resumo:
DUE TO COPYRIGHT RESTRICTIONS ONLY AVAILABLE FOR CONSULTATION AT ASTON UNIVERSITY LIBRARY AND INFORMATION SERVICES WITH PRIOR ARRANGEMENT The research presented in this thesis is concerned with Discrete-Event Simulation (DES) modelling as a method to facilitate logistical policy development within the UK Less-than-Truckload (LTL) freight distribution sector which has been typified by “Pallet Networks” operating on a hub-and-spoke philosophy. Current literature relating to LTL hub-and-spoke and cross-dock freight distribution systems traditionally examines a variety of network and hub design configurations. Each is consistent with classical notions of creating process efficiency, improving productivity, reducing costs and generally creating economies of scale through notions of bulk optimisation. Whilst there is a growing abundance of papers discussing both the network design and hub operational components mentioned above, there is a shortcoming in the overall analysis when it comes to discussing the “spoke-terminal” of hub-and-spoke freight distribution systems and their capabilities for handling the diverse and discrete customer profiles of freight that multi-user LTL hub-and-spoke networks typically handle over the “last-mile” of the delivery, in particular, a mix of retail and non-retail customers. A simulation study is undertaken to investigate the impact on operational performance when the current combined spoke-terminal delivery tours are separated by ‘profile-type’ (i.e. retail or nonretail). The results indicate that a potential improvement in delivery performance can be made by separating retail and non-retail delivery runs at the spoke-terminal and that dedicated retail and non-retail delivery tours could be adopted in order to improve customer delivery requirements and adapt hub-deployed policies. The study also leverages key operator experiences to highlight the main practical implementation challenges when integrating the observed simulation results into the real-world. The study concludes that DES be harnessed as an enabling device to develop a ‘guide policy’. This policy needs to be flexible and should be applied in stages, taking into account the growing retail-exposure.
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Os perfis enformados a frio estão em crescente uso na indústria da construção, utilizados como estruturas secundárias e primárias, por apresentar resistência em relação ao baixo peso, facilidade de utilização em obra e sustentabilidade. A norma europeia EN1993-1-3, também adotada em Portugal, que apresenta as especificações normativas sobre o uso estrutural de perfis enformados a frio é de difícil aplicação para os projetistas devido à quantidade e complexidade de cálculos para que sejam efetuadas as verificações de segurança necessárias, pelas limitações dos programas informáticos e complexidade de compreensão dos fenómenos da instabilidade local e distorcional que condicionam o comportamento deste tipo de secções, classificadas como de classe 4. O presente trabalho procura explicar os procedimentos do eurocódigo e os seus aspetos mais controversos, como, por exemplo, o processo de cálculo da distribuição de tensões numa secção arbitrária constituída por segmentos retos, o cálculo de larguras efetivas e espessuras reduzidas e as verificações de segurança em termos de resistência e estabilidade global requeridos pela norma. O principal objetivo deste trabalho é o desenvolvimento um programa de cálculo para verificar barras com secções de classe 4 que tenha a abrangência das especificações do Eurocódigo (EC3-1-3), que possa auxiliar engenheiros no processo de projeto, dimensionamento e verificação regulamentar de estruturas metálicas que utilizem este tipo de secções. Para isso foi criada uma aplicação informática, em ambiente Windows®, que está ligada ao programa Autodesk® Robot Structural Analisys® para obtenção de dados de cálculo e executar os cálculos de secções efetivas e verificações de segurança de acordo com a norma europeia. São apresentados diagramas de blocos com a sequência do procedimento de cálculo das várias fases de cálculo de secções efetivas e de verificação de barras, com vista a mostrar a lógica de funcionamento interno da aplicação criada no âmbito deste trabalho. Por fim desenvolve-se um manual de utilização da aplicação e um exemplo comparativo, de cálculo das propriedades efetivas de uma secção, entre os resultados do programa e documentos de referência com cálculos manuais
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En este trabajo presentamos algunos avances de una investigación orientada a comprender cómo inciden las perspectivas de actores en el moldeamiento de políticas y programas de abordaje de la heterogeneidad estudiantil implementados en el tramo inicial de la Facultad de Informática de la Universidad Nacional de La Plata, en la que se dicta una carrera de Ingeniería en Computación1. El relevamiento permitió reconocer quiénes tienen papeles protagónicos en la definición y desarrollo de estrategias de atención a la diversidad estudiantil. Nuestro trabajo pretende dar cuenta de las conceptualizaciones que los actores indagados construyen acerca de la heterogeneidad y la diferencia en el marco de la implementación de políticas institucionales. Presentaremos análisis basados en el relevamiento efectuado y en debates del campo educativo. Esbozaremos algunas conclusiones provisorias referidas a las perspectivas de la heterogeneidad y la diferencia prevalecientes entre los informantes clave y el contraste entre éstas y las culturas y tradiciones que orientan el trabajo en las aulas
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En este trabajo presentamos algunos avances de una investigación orientada a comprender cómo inciden las perspectivas de actores en el moldeamiento de políticas y programas de abordaje de la heterogeneidad estudiantil implementados en el tramo inicial de la Facultad de Informática de la Universidad Nacional de La Plata, en la que se dicta una carrera de Ingeniería en Computación1. El relevamiento permitió reconocer quiénes tienen papeles protagónicos en la definición y desarrollo de estrategias de atención a la diversidad estudiantil. Nuestro trabajo pretende dar cuenta de las conceptualizaciones que los actores indagados construyen acerca de la heterogeneidad y la diferencia en el marco de la implementación de políticas institucionales. Presentaremos análisis basados en el relevamiento efectuado y en debates del campo educativo. Esbozaremos algunas conclusiones provisorias referidas a las perspectivas de la heterogeneidad y la diferencia prevalecientes entre los informantes clave y el contraste entre éstas y las culturas y tradiciones que orientan el trabajo en las aulas
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En este trabajo presentamos algunos avances de una investigación orientada a comprender cómo inciden las perspectivas de actores en el moldeamiento de políticas y programas de abordaje de la heterogeneidad estudiantil implementados en el tramo inicial de la Facultad de Informática de la Universidad Nacional de La Plata, en la que se dicta una carrera de Ingeniería en Computación1. El relevamiento permitió reconocer quiénes tienen papeles protagónicos en la definición y desarrollo de estrategias de atención a la diversidad estudiantil. Nuestro trabajo pretende dar cuenta de las conceptualizaciones que los actores indagados construyen acerca de la heterogeneidad y la diferencia en el marco de la implementación de políticas institucionales. Presentaremos análisis basados en el relevamiento efectuado y en debates del campo educativo. Esbozaremos algunas conclusiones provisorias referidas a las perspectivas de la heterogeneidad y la diferencia prevalecientes entre los informantes clave y el contraste entre éstas y las culturas y tradiciones que orientan el trabajo en las aulas
Resumo:
The subject Responsibility Enterprise Social (RSE) is relatively recent in the half national academic and the world of the management businesses as practical. For the lack of socialization of experiences and clarity of concepts, shunting lines in the agreement of the subject and the conduction of the interventions occur. It was looked to inquire, in this research, the development of the project of Social Responsibility Enterprise ―School of Computer science and Citizenship‖ of a situated company in the State of Pará, objectifying to evaluate it and later to understand it. For this, one searched to describe the characteristics and structure of the School, to identify to the lines and lines of direction adopted for this Project and to identify to the influence and results of the same in the life of pupils, professors and egresses of the School. It is characterized for a study of case with qualitative boarding of descriptive character, carried through interviews structuralized in a sample of 21 divided members of the School between professors, pupils and egresses. It was used of the analysis of categorical content, having as axle for the interpretation of the data the Social Responsibility, the Digital Inclusion and the Education. The gotten results inform that the infrastructure has challenges to face, point disparities between the conception and practical of the categories characterized in the Politician-Pedagogical Project of the EIC and the influence that, exactly under limits, the life of the professors, pupils reaches and egress. One evidenced that Social action for damages of this company when come back toward this project, they had not been evidenced. For this prism, these actions had only remained in the assistencialist speech and not structural, being thus, the company is not fulfilling its paper of transforming element of the reality of its clientele and the population that lives in it s around
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Thesis (Master's)--University of Washington, 2016-08
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Abstract not available