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In the environment of network economy is current problem of logistics management area an question of collaborative planning of serial manufacturing in small and medium enterprises. Present progressive production systems with connection in complex and extensiveness of network environment is put increasing requirements on the area of design and execution of logistics plans, which could be realised on condition of excellent knowledge and evaluation of network environment. On the basis of thesis research is constitute initial categorization of basic logistics terms definition and comparation i. e. network, collaboration and production systems. The main framework of dissertation is based on survey of planning in present progressive forms of production systems up to the present agile forms of manufacturing systems. In dissertation thesis is designed and verified a new methodology of logistics network evaluation, which pay attention on collaborative planning procedure in logistics network in connection with external environment of network. A new logistics network methodology contains element supplier evaluation, time and product structure attributes of collaborative plans fulfilment and subsequent logistics controlling.

Made available in DSpace on 2016-04-04T18:31:34Z (GMT). No. of bitstreams: 1 Carlos Alberto Tercariol Bergonso.pdf: 948199 bytes, checksum: 9baee66f05960fc08d06f925a9ea859a (MD5) Previous issue date: 2012-12-07 / The present dissertation proposes a 802.11 network evaluation sequence which can be adopted, independently of the equipment used at the network. The log-distance path loss model is used for the environment characterization (by the model ? parameter) where the network is evaluated. The specific objectives of each evaluation stage are presented and contextualized. The full proposal has initial steps related to the information determination which will be used as references of equipment location and data, and of network performance. Those reference data will be later compared to the handled data obtained from measurements related to the physical and MAC (Medium Access Control) layer performance and behavior, as well as to the transport layer. By the end, one stage to consolidate the measured data is necessary in order to determine a single final result, weigh up according to the specific objectives of the network and/or equipment evaluation. However, the work focus is at the equipment data obtaining stage and at the lower layers (physical and MAC) performance/behavior determination, so that evaluation methods are developed for those two stages. It is demonstrated that the effective transmission physical layer data rates vary much more than what is expected due to the interpretation of the data provided by equipment manufactors. And that better performance could be obtained from complex networks, which made use of multiple access points, installed at unfavorable propagation environments, depending upon the network project. / A presente disserta??o prop?e uma sequ?ncia de avalia??o para redes 802.11 que pode ser adotada, independentemente de quais s?o os equipamentos utilizados na rede. O modelo de log-distance path loss ? utilizado para caracteriza??o do ambiente (pelo par?metro ? do modelo) em que a rede ? avaliada. Os objetivos espec?ficos de cada uma das etapas de avalia??o s?o apresentadas e contextualizadas. A proposta, em sua totalidade, apresenta etapas iniciais relacionadas ? determina??o de informa??es que ser?o usadas como refer?ncias de localidade e desempenho de rede, e de dados dos equipamentos. Esses dados de refer?ncia ser?o posteriormente comparados com os dados coletados e tratados de medi??es realizadas em rela??o ao desempenho e comportamento das camadas f?sicas e MAC (Medium Access Control) e da camada de transporte. Por fim, uma etapa de consolida??o dos resultados das medi??es ? necess?ria para se obter um resultado final ?nico, composto de forma a ponderar de acordo com o(s) objetivo(s) espec?fico(s) de avalia??o da rede e/ou equipamento. O foco dessa disserta??o, contudo, est? na obten??o de dados dos equipamentos, de desempenho e comportamento das camadas inferiores (f?sica e MAC), de forma que para essas etapas, m?todos de avalia??o s?o desenvolvidos. ? demonstrado que as taxas de transmiss?o de dados efetivamente praticadas na camada f?sica variam muito mais que o esperado em fun??o da interpreta??o dos dados fornecidos pelos fabricantes de equipamentos. E que, dependendo do projeto da rede, pode-se obter melhores desempenhos em ambientes de propaga??o desfavor?vel que utilizam m?ltiplos pontos de acesso.

This study was a user oriented evaluation of the South African Non-government Organizations Network (SANGONeT), a regional electronic information and communication network for development and human rights workers. SANGONeT emphasizes the need for integrating a variety of information related tasks through the use of information and communication technologies (lCT). Its mission is to facilitate the effective and empowering use of ICTs by development and social justice actors in Southern Africa. While SANGONeT is one of the oldest networks for development and human rights sectors in South Africa, no other evaluations of this particular network, from the users' perspective could be traced. The study sought to determine SANGONeT's intended users' perceptions of the network, in terms of their level of awareness and, utilization, accessibility, relevance of the network and its level of facilitation in networking. SANGONeT was evaluated using effectiveness indicators. The respondents were the development and human rights organizations in K waZulu-Natal which subscribed to SANGONeT, or those which use certain services provided by the network as well as those which do not use the network but which are potential users. The SANGONeT subscribers formed only a small proportion of the population. They were all included in the study. A number of potential subscribers who were nonsubscribers were added. According to the findings, the subscribers were satisfied with the services that SANGONeT provides and they do see it as a networking facilitator. The nonsubscribers and the nonusers were not aware of the network's existence or the services it provides. Underutilisation does not result from the problems of accessibility and relevance. Lack of awareness emerged as the main reason for the underutilisation of SANGONeT in KwaZulu-Natal. Based on the findings of the study, recommendations are made for SANGONeT as well as suggestions for further study. / Thesis (M.I.S.)-University of Natal, Pietermaritzburg, 2001.

The field buses, and particularly the ‘PROFIBUS’, are currently widely used in automation systems, with the intention to automate industrial applications. It is of the utmost importance that one should understand how these systems operate, because failure to understand may result in improper applications, which can ultimately lead to intense network problems and, consequently, lead to potential catastrophic failures in industrial equipment, as well as compromising the health and safety of the people. This research was the performance evaluation of SAMANCOR PROFIBUS network that controls the chrome manufacturing plant. The problem with the network was that it was failing intermittently. These network failures resulted in loss of production, loss of throughput, compromised quality, downtime due to reworks, high costs in energy used to rework, and equipment damage or failure. One of the OBJECTIVES of the research was to carry out a performance evaluation of the PROFIBUS network in terms of the possible electromagnetic interference (EMI) within the plant’s PLC network. This topic emanated from the network service providers that kept insisting that the network was unstable, due to possible electromagnetic interference caused by possible high voltage cables running next to the plant network cables. This assumption was without fact, and hence the research was conducted. The QUANTITATIVE research method was used to conduct the research, where simulation of the plant network, using external parameters, were used to carry out the research. Furthermore, experiments were conducted and the physical measurements were performed on the network, where parameters derived from these measurements were used to compare the two networks. In essence, the network was tested under known configurations. The manner in which the network was simulated was that of stepping up the electrical current from the external device, and recording the response of the network. A stand-alone network rig was built and used to carry out the tests, and the results were compared with those obtained from the plant network. / Electrical and Mining Engineering / M. Tech. (Electrical Engineering)