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[IN]EVIDENT ECOLOGIES : Embodying Operational Landscapes. Exploring how the embodiment of hidden narratives and situated knowledge can spread awareness of operational landscapesLandstedt, Ebba January 2024 (has links)
The demand for ‘green’ resources is growing, and in response to this, industrial expansion in northern Sweden is accelerating, leaving little room for a thorough examination of long-term consequences from ecological and social perspectives. Resource extraction in Sweden is nothing new, and some areas still deal with the consequences of previously hastily induced industrialism. This research explores how embodied experiences can be utilized to convey the hidden narratives of a riverine landscape affected by extractive industries, more precisely the area around Áhkájávvre situated in the Luleå River, and how situating oneself within these embodied narratives can contribute to raising public awareness of their ecological and cultural impacts. To support this research question, theories of situated knowledge are introduced, which advocate for the subjective knowledges of the landscape’s ecology and the embodiment of the agents in it. By highlighting the perspectives of its ecology, this thesis aims to connect the urban and the hinterlands - the operational landscapes and change how we view them. The research is conducted through interviews and case studies, followed by a design-as- research methodology, a process-based project which explores various methods of artistic research representation as mediators to situate the observer in the subject and embody the knowledge of the site. It is explored through two perspectives: the area of disturbance (the operational landscape) and the disruptor (us), through the scope of social and ecological dimensions, represented by ‘the people’ and ‘the soil’. This research presents scenarios and explorations aimed at increasing connection to, and raising public awareness of, resource extraction, both historical and ongoing. These scenarios highlight the local effects of the affected area, and the interconnectedness of operational landscapes and urban environments. This research contributes to the understanding of the need for embodied experiences in developing an understanding of the hidden consequences of resource extraction on operational landscape, and to situate oneself in its context.
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Assessing Effects of Object Detection Performance on Simulated Crash Outcomes for an Automated Driving SystemGalloway, Andrew Joseph 11 July 2023 (has links)
Highly Automated Vehicles (AVs) have the capability to revolutionize the transportation system.
These systems have the possibility to make roads safer as AVs do not have limitations that human drivers do, many of which are common causes of vehicle crashes (e.g., distraction or fatigue) often defined generically as human error. The deployment of AVs is likely to be very gradual however, and there will exist situations in which the AV will be driving in close proximity with human drivers across the foreseeable future. Given the persistent crash problem in which the makority of crashes are attributed to driver error, humans will continue to create potential collision scenarios that an AV will be expected to try and avoid or mitigate if developed appropriately.
The absence of unreasonable risk in an AVs ability to comprehend and react in these situations is referred to as operational safety. Unlike advanced driver assistance systems (ADAS), highly automated vehicles are required to perform the entirety of the dynamic driving task (DDT) and have a greater responsibility to achieve a high level of operational safety. To address this concern, scenario-based testing has increasingly become a popular option for evaluating AV performance. On a functional level, an AV typically consists of three basic systems: the perception system, the decision and path planning system, and vehicle motion control system. A minimum level of performance is needed in each of these functional blocks to achieve an adequate level of operational safety.
The goal of this study was to investigate the effects that perception system performance (i.e., target object state errors) has on vehicle operational safety in collision scenarios similar to that created by human drivers. In the first part of this study, recent annual crash data was used to define a relevant crash population of possible scenarios involving intersections that an AV operating as an urban taxi may encounter. Common crash maneuvers and characteristics were combined to create a set of testing scenarios that represent a high iii percentage of the overall crash population. In the second part of this study, each test scenario was executed using an AV test platform during closed road testing to determine possible real-world perception system performance. This provided a measure of the error in object detection measurements compared to the ideal (i.e., where a vehicle was detected to be compared to where it actually was). In the third part of this study, a set of vehicle simulations were performed to assess the effect of perception system performance on crash outcomes. This analysis simulated hypothetical crashes between an AV and one other collision partner.
First an initial worst-case impact configuration was defined and was based on injury outcomes seen in crash data. The AV was then simulated to perform a variety of evasive maneuvers based on an adaptation of a non-impaired driver model. The impact location and orientation of the collision partner was simulated as two states: one based on the object detection of an ideal perception system and the other based on the object detection of the perception system from the AV platform used during the road testing. For simulations in which the two vehicles contacted each other, a planar momentum-impulse model was used for impact modeling and injury outcomes were predicted using an omni-directional injury model taken from recent literature.
Results from this study indicate that errors in perception system measurements can change the perceived occupant injury risk within a crash. Sensitivity was found to be dependent on the specific crash type as well as what evasive maneuver is taken. Sensitivities occurred mainly due to changes in the principal direction of force for the crash and the interaction within the injury risk prediction curves. In order to achieve full operational safety, it will likely be important to understand the influence that each functional system (perception, decision, and control) may have on AV performance in these crash scenarios. / Master of Science / Highly Automated Vehicles (AVs) have the capability to revolutionize the transportation system.
These systems have the possibility to make roads safer as AVs do not have many of the limitations that human drivers do, many of which are common causes of vehicle crashes (e.g., distraction or fatigue). AVs will be expected to drive alongside human drivers, and so these drivers are likely to continue to be at fault in causing crashes. As part of ensuring safety, AVs will reasonably be expected to try and avoid or help reduce the severity of these crashes. AVs operate using three main systems: the perception system which consists of sensors that see the objects around the AV, the decision and path planning system, which makes decision on what the AV will do, and the vehicle motion control system. Due to the nature of the real-world, these systems may not work exactly as intended which may affect the ability of the AV to react to possible crash scenarios. Because of this, the goal of this study was to investigate the effects that perception system performance (i.e., target object state errors) has on the ability of an AV to react to crash scenarios similar to those created by human drivers. This study first defined crash scenarios using real-world crash data. A real-world perception system was then tested in these scenarios to determine object detection performance.
Based on this performance, effects on safety were assessed through vehicle crash simulations. Results from this analysis showed that safety can vary based on both perception system performance and crash scenario.
This highlights that it will be important to address system performance in order to achieve high levels of driving safety.
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“I’m Not Gonna Be Able to Do This for Much Longer:” Perspectives of Parochial School Principals on Their Role in Operational Vitality and the Educational MarketplaceBrough, Kris 12 July 2024 (has links) (PDF)
Catholic schools have confronted a complex array of challenges, including declining enrollments, shifting demographics, and financial strains affecting all stakeholders. Establishing effective leadership has been a persistent practical hurdle, particularly in parish-based schools operating within the local-executive model. This qualitative study delved into the experiences and perspectives of parochial school principals, focusing on their leadership role in operational vitality. Additionally, it examined how these principals navigate the evolving educational landscape and respond to emerging challenges. By gathering and analyzing narratives from principals, the study shed light on issues impacting operational vitality and institutional growth and calls for further exploration within the field. The findings underscored principals’ adeptness in addressing challenges within the educational marketplace and highlighted areas of necessary evolution, particularly regarding enrollment and funding, with implications for the sustainability of Catholic schooling.
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The impact of real time shop floor information on operational decision makingVermaak, Martin 29 June 2011 (has links)
The concept of Operational decision making is not new, but in the context of Enterprise
Resource Planning implementation as is the case at PFK Electronics (PTY) Ltd., it
becomes part of what ERP process that makes organisations more competitive and
profitable as Wallace and Kremzar (2001) comment, "Effective forecasting, planning,
and scheduling is fundamental to productivity and ERP is a fundamental way to achieve
it. Properly implementing ERP will give you a competitive advantage and help you run
your business more effectively, efficiently and responsively."
The Operational decision making process that forms part of the research question is a
process known as Sales and Operational Planning process (SOP's). The research
paper is looking at how Real Time Shop floor information can impact on the decision
making process, as Wallace and Kremzar (2001 : 165) state that this is the most
important element in making ERP systems work.
The study looks at what information is required to make effective decisions in the SOP's
process and how the respondents perceive information quality, its value and the impact
on decision making in the SOP's process. The research sought to further investigate a
diverse demographic population, the behavioural culture within the organisation and
their perception on having this information in real time directly from the shop floor. Data
was collected via a survey questionnaire and an interview process which also required
the review of organisational documentation where available.
The research aimed to investigate what information Operations (SOP's) need to make
effective decisions to meet the organisational strategic objectives and to determine the
best means of obtaining and communicating the information to managers. Developing
this further the research was then broken down into three objectives:
• To investigate 'what' information sales and operations managers need in order to
make effective decisions that will have an impact on them meeting strategic
performance objectives. • To evaluate 'how' real time shop floor information can improve the decision
making process in Operations in meeting strategic objectives; by understanding
the types and methods used in decision making and the significance of time on
information.
• To recommend suitable Information Communication Technology (ICT) systems
to obtain and communicate information to managers effectively within operations.
During this process time constraints were of a concern, which manifested in objective
three not being able to be completed to the satisfaction of the researcher. However the
research process, which included the survey and interviews of respondents, the
researcher felt that respondents where honest and open in expressing their views which
adds to the validity and reliability of the research.
The results showed that there was a clear understanding of the topic amongst the
respondents. It showed that the respondents had a good understanding of information
and its importance in meeting strategic objectives by making better decisions. It became
clear that ERP was generally working well but that timeliness of information was the
biggest obstacle in meeting strategic objectives in balancing supply and demand. The
research identified the information necessary for the SOP's process to be effective and
it also showed the impact of having real time shop floor information available to the
decision making process. It also showed that there would be other benefits as
performance could also be improved by having real time performance indicators that are
used to set the pace and common goal.
The report also identified some cultural differences between PFK electronics culture and
NUMSA unionised employees culture and the impact it has on relationships and
communication.
The report concludes with the research question being answered and with a
recommendation that the single most important means of improving operational
effectiveness is going to be to improve the quality of information used in decision making. The research has shown that getting this information in 'real time' or as close
as possible to real time is the best means of improving the quality of information and its
impact on management decisions. It is further recommended to investigate the
implementation of systems such as Manufacturing Execution Systems to link the shop
floor directly into the current ERP system and lastly to find a means of bridging the
cultural differences between NUMSA unionised employees and PFK behavioural
culture. / Graduate School of Business Leadership / M.B.A.
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The impact of real time shop floor information on operational decision makingVermaak, Martin 29 June 2011 (has links)
The concept of Operational decision making is not new, but in the context of Enterprise
Resource Planning implementation as is the case at PFK Electronics (PTY) Ltd., it
becomes part of what ERP process that makes organisations more competitive and
profitable as Wallace and Kremzar (2001) comment, "Effective forecasting, planning,
and scheduling is fundamental to productivity and ERP is a fundamental way to achieve
it. Properly implementing ERP will give you a competitive advantage and help you run
your business more effectively, efficiently and responsively."
The Operational decision making process that forms part of the research question is a
process known as Sales and Operational Planning process (SOP's). The research
paper is looking at how Real Time Shop floor information can impact on the decision
making process, as Wallace and Kremzar (2001 : 165) state that this is the most
important element in making ERP systems work.
The study looks at what information is required to make effective decisions in the SOP's
process and how the respondents perceive information quality, its value and the impact
on decision making in the SOP's process. The research sought to further investigate a
diverse demographic population, the behavioural culture within the organisation and
their perception on having this information in real time directly from the shop floor. Data
was collected via a survey questionnaire and an interview process which also required
the review of organisational documentation where available.
The research aimed to investigate what information Operations (SOP's) need to make
effective decisions to meet the organisational strategic objectives and to determine the
best means of obtaining and communicating the information to managers. Developing
this further the research was then broken down into three objectives:
• To investigate 'what' information sales and operations managers need in order to
make effective decisions that will have an impact on them meeting strategic
performance objectives. • To evaluate 'how' real time shop floor information can improve the decision
making process in Operations in meeting strategic objectives; by understanding
the types and methods used in decision making and the significance of time on
information.
• To recommend suitable Information Communication Technology (ICT) systems
to obtain and communicate information to managers effectively within operations.
During this process time constraints were of a concern, which manifested in objective
three not being able to be completed to the satisfaction of the researcher. However the
research process, which included the survey and interviews of respondents, the
researcher felt that respondents where honest and open in expressing their views which
adds to the validity and reliability of the research.
The results showed that there was a clear understanding of the topic amongst the
respondents. It showed that the respondents had a good understanding of information
and its importance in meeting strategic objectives by making better decisions. It became
clear that ERP was generally working well but that timeliness of information was the
biggest obstacle in meeting strategic objectives in balancing supply and demand. The
research identified the information necessary for the SOP's process to be effective and
it also showed the impact of having real time shop floor information available to the
decision making process. It also showed that there would be other benefits as
performance could also be improved by having real time performance indicators that are
used to set the pace and common goal.
The report also identified some cultural differences between PFK electronics culture and
NUMSA unionised employees culture and the impact it has on relationships and
communication.
The report concludes with the research question being answered and with a
recommendation that the single most important means of improving operational
effectiveness is going to be to improve the quality of information used in decision making. The research has shown that getting this information in 'real time' or as close
as possible to real time is the best means of improving the quality of information and its
impact on management decisions. It is further recommended to investigate the
implementation of systems such as Manufacturing Execution Systems to link the shop
floor directly into the current ERP system and lastly to find a means of bridging the
cultural differences between NUMSA unionised employees and PFK behavioural
culture. / Graduate School of Business Leadership / M.B.A.
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Qualidade, desempenho operacional e custos de plantios, manual e mecanizado, de Eucalyptus grandis, implantados com cultivo mínimo do solo / Quality, operational performance and cost of eucalyptus grandis hand and machine planting, implemented with minimal tillage.Fessel, Vitor Augusto Graner 03 July 2003 (has links)
O método de plantio manual de mudas de árvores é predominante no Brasil. Para a redução dos custos com mão-de-obra, aumento de produtividade e qualidade operacional, o plantio manual deve ser substituído total ou parcialmente por operações mecanizadas. Com esse enfoque foram avaliadas as atividades de plantios manual e mecanizado de eucaliptos, bem como de preparo mecanizado do solo, em área pertencente a uma empresa florestal. O plantio manual foi feito por onze trabalhadores rurais, com o uso da transplantadora de acionamento manual. O plantio mecanizado foi realizado por uma máquina de transplantio de mudas, operada por um trabalhador rural e tracionada por um trator. Na área do estudo foram locadas duas parcelas amostrais, formando uma malha de setenta e cinco pontos amostrais para cada sistema de plantio. Os itens do preparo do solo avaliados foram a profundidade do sulco, o diâmetro dos torrões e o volume cilíndrico dos galhos de madeira sobre a faixa de sulcamento. O itens dos sistemas de plantio avaliados foram a presença de defeitos da operação, a distância entre plantas, a altura da parte aérea das mudas e a sobrevivência das plantas após um mês de idade. As ferramentas da qualidade total utilizadas foram os histogramas, o diagrama de causa e efeito, os gráficos de Pareto e de controle. As análises estatísticas dos resultados foram feitas pelo teste t e pelo teste de qui-quadrado Para avaliar o desempenho operacional do sistema manual estimou-se somente a capacidade de campo operacional. No sistema mecanizado foram estimadas as capacidades de campo efetiva e operacional. Nos dois sistemas de plantio foram estimados também os custos horários e operacionais das máquinas e da mão-de-obra. Entre os sistemas de plantio, a distância entre plantas foi diferente estatisticamente, com melhor distribuição das mudas no sistema manual. O número de defeitos por muda plantada foi semelhante estatisticamente entre os sistemas de plantio. Os principais defeitos do sistema manual foram as mudas plantadas com colo encoberto pelo solo e as mudas plantadas fora do centro do sulco, os quais representaram 72,8% do total. No sistema mecanizado, esses defeitos, somados às mudas não plantadas e mudas não firmes, representaram 76,7% do total. A altura da parte aérea foi diferente estatisticamente, tanto no plantio como um mês após. A sobrevivência das mudas efetivamente plantadas, após um mês de idade, foi semelhante estatisticamente. Concluiu-se, assim, que a qualidade em ambos os sistemas de plantio não variaram dentro de padrões aceitáveis pela empresa florestal. O tempo produtivo do sistema de plantio mecanizado foi igual a 48,2%, gerando uma capacidade de campo operacional 60,0% menor do que no sistema manual. Inferiu-se que o número médio de mudas plantadas por trabalhador por hora foi igual a 95 no sistema manual, enquanto que no sistema mecanizado foi igual a 205. O custo operacional estimado do sistema mecanizado foi 44,9% maior do que no sistema manual, fato devido a baixa capacidade de campo operacional observada no sistema mecanizado. / Hand planting of tree seedlings is the predominant method in Brazil. In order to reduce labor costs, increase productivity, and improve operational quality, hand planting should be totally or partially replaced by machine operations. Having this in mind, eucalyptus hand and machine planting activities were assessed, as well as those of mechanical tillage, in an area belonging to a forestation company. Hand planting had been carried out by 11 rural workers by using a planting tube. Machine planting had been carried out by using a seedling transplant machine, which was operated by a rural worker and pulled by a tractor. In the study area, two sampling parts were allocated, forming a web with 75 sampling points for each planting system. Tillage items that were assessed included furrow depth, stone diameter, and the cylindrical volume of wood branches on the furrow belt. Planting system items that were assessed included the presence of operation defects, distance between plants, height of the top portion of the seedlings, and plant survival after one month of age. Total quality tools included histograms, cause and effect diagram, control graphs, and Pareto's graphs. Statistical analyses of the results were performed by using test and qui-square test. To evaluate hand planting systems operational performance, only the operational field capacity was estimated. As for the machine system, effective and operational field capacities were estimated. Labor and machine hourly costs, as well as the operational costs for both planting systems were assessed. When comparing planting systems, the distance between plants was statistically different, with hand planting system showing better seedling distribution. The number of defects per planted seedling was statistically similar for both planting systems. The major defects in the hand planting system were seedlings planted with soil-covered base and those planted out of the furrow center, which represented 72.8% of the total. With the machine system, these defects, in addition to non-planted and loose seedlings, represented 76.7% of the total. The height of the top portion was statistically different, both when planting and after one month. The survival of effectively planted seedlings after one month of age was statistically similar. Thus, we concluded that the quality of both planting systems did not vary within the standards that are acceptable for the forestation company. Machine planting system's productive time was 48.2%, and generated an estimated operational field capacity 60.0% less to that for the hand planting system. The average number of planted seedlings per worker by hour was inferred to be equal to 95 in the hand planting system, whereas it was equal to 205 in the machine system. The operational cost for the machine system was estimated to be 44.9% greater to that for the hand planting system, which is due to the low operational field capacity observed in the machine system.
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Análise econômica financeira das alianças estratégicas entre as empresas concorrentes do tipo pseudo-concentração: o caso da aliança entre TAM e VARIGLucini, Juliana 02 March 2006 (has links)
Made available in DSpace on 2015-03-05T19:12:38Z (GMT). No. of bitstreams: 0
Previous issue date: 2 / Nenhuma / A estrutura e a estratégia das organizações são afetadas pela competitividade, intensificada nas últimas décadas. Devido a isso, as entidades buscam estratégias para continuarem ou se tornarem competitivas no mercado, sendo uma delas a procura por alianças estratégicas com outras organizações, atuantes ou não no mesmo mercado. Esta é a razão que motivou a realização do presente estudo, cujo objetivo foi verificar os reflexos das alianças estratégicas nos resultados econômicos das empresas que a adotam, usando como referencial o caso TAM e VARIG durante sua duração. Para tanto, realizou-se uma pesquisa documental a partir das demonstrações contábeis de VARIG e TAM para descrever possíveis impactos oriundos do compartilhamento de vôos ocorridos entre os anos de 2003 a 2005. Verificou-se que a aliança estratégica produziu resultados positivos para ambas as empresas, contudo seus efeitos benéficos puderam ser colhidos em maior proporção pela VARIG, através de uma redução de custos e despesas mais representativas / The structure and the strategy of the organizations have being affected by the international competition intensified in the last decades. Because of this concurrency the entities have being searching strategies in order to remain competitive in the market being one of them to look for partnership with other companies. This is the reason that motivated the present study which general main aim is to verify the reflexes of strategic alliances in the economic income of the companies that adopted it, using as reference the case of TAM and VARIG during their partnership. The methodology of this present study is classified as for the technical proceedings like “documental” therefore financial statements of VARIG and TAM are used to describe possible impacts from the partaking of flights occurred from 2003 until 2005. The method of research used gave us the possibility to conclude that the strategic alliance probably influenced the reduction of operational costs and expenses of both companies during the period of tim
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O papel da estratégia de operações na competitividade empresarial: uma vantagem competitiva para a liderança de mercado? A situação da empresa brasileira - um estudo exploratório. / The role of operational strategy in business competitiveness. A competitive edge for market leadership? The Brazilian Enterprise - an exploratory study.Pilão, Nivaldo Elias 24 May 2006 (has links)
O mundo moderno tem exigido das empresas uma força competitiva que deve se moldar aos diferentes segmentos de mercado e tipos de organizações. Vários são os exemplos de empresas que posicionam as suas operações no centro da estratégia competitiva, qualificando-as como uma força capaz de levá-las a modificar a seu favor a estrutura de mercado em que competem. Assim, tomando-se por base que a competitividade empresarial está diretamente associada à capacidade da organização de entender e atender as expectativas dos clientes, e que isto pode ser conseguido, em especial, pelo setor de operações, por meio da produtividade e da qualidade, por meio de sua eficiência interna e externa, o objetivo do presente trabalho é estudar as estratégias operacionais e refletir sobre a maneira como elas podem contribuir para conduzir as empresas à liderança de mercado ou funcionar como uma barreira contra a ameaça de novos entrantes. Mediante estudo exploratório da situação das empresas brasileiras, por meio dos casos das empresas Brasilata S.A. Embalagens Metálicas e Gol Linhas Aéreas Inteligentes S.A., a Tese demonstra que é possível posicionar as operações de forma a obter a desejada vantagem competitiva. / The modern world demands from companies a competitive force that must mold itself to different market segments and types of organizations. There are various examples of companies that position their operations in the center of competitive strategy, qualifying them as a force capable of allowing them to modify in their favor the market structure in which they compete. Thus, given that entrepreneurial competitiveness is directly associated with the organizational capacity to understand and satisfy customers expectations and that this can be achieved by the operational sector, by means of productivity and of quality and by means of internal and external efficiency, the aim of the present work is to study the operational strategies and the way in which they can contribute to conduct companies to market leadership or function as a barrier against the threat of new entrants. Through an exploratory study of the situation of Brazilian companies, using the cases of Brasilata S.A. Embalagens Metálicas and Gol Linhas Aéreas Inteligentes S.A., this thesis shows that it is possible to position the operations in such a way as to obtain the desired competitive advantage.
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Universalização da energia elétrica através da tecnologia cabos pára-raios energizados (PRE) / Universalization of electrical energy services through the energized shield wire line technology (SWL)José Ezequiel Ramos 29 April 2010 (has links)
A universalização da energia elétrica, como uma das principais políticas públicas de inclusão social, tem como desafio a escolha de alternativas tecnológicas capazes de conciliar os aspectos de viabilidade técnica e econômica. A Tecnologia cabos para-raios energizados (PRE), objeto de estudo desta tese, se insere neste contexto. Assim, este trabalho consiste na análise de viabilidade do PRE no esquema trifásico, cuja instalação é associada à linha de transmissão 230 kV do sistema de transmissão de Rondônia. São analisados os aspectos de seu desempenho técnico, operacional e econômico. No aspecto técnico é analisado o desempenho do sistema de aterramento quanto à resistência de terra, tensões de toque e de passo, além de análise da queda de tensão, desequilíbrio de tensão e capacidade de carregamento da instalação. A abordagem técnica é aprofundada após análise do desempenho operacional avaliado a partir da classificação das interrupções verificadas em mais de 180 meses de operação do Sistema PRE Rondônia. Em decorrência dessa avaliação, são obtidos índices operacionais de continuidade, analisados comparativamente em relação a outras alternativas tecnológicas, visando analisar a viabilidade da Tecnologia PRE. Uma das constatações resultantes da análise das causas das interrupções indica um elevado impacto das descargas atmosféricas no desempenho do PRE. Este aspecto é extensivamente analisado quanto aos efeitos das descargas diretas e indiretas sobre a instalação, partindo-se de medições de campo nos contrapesos das torres, medições de resistividade do solo e ensaios na cadeia de isoladores do PRE. Simulações são realizadas utilizando-se os programas computacionais ATPDraw, ERM e CDEGS para análise das tensões resultantes de descargas diretas, tensões induzidas por descargas indiretas e cálculo de resistência de terra, respectivamente. São investigados os efeitos de parâmetros importantes no desempenho do sistema frente a descargas atmosféricas e comparados os números de interrupções estimadas e verificadas em campo, partindo-se de um roteiro metodológico minuciosamente detalhado, a fim de permitir a repetição dos procedimentos em situações semelhantes às analisadas neste trabalho. Após uma análise comparativa do desempenho do sistema PRE em relação a outras alternativas convencionais, são estabelecidos índices de referência para o desempenho operacional da Tecnologia PRE e desenvolvida uma análise econômica da implantação dessa tecnologia em Rondônia. / As one of the major public policies of social inclusion, the universalization of electric energy services has as a challenge to choose appropriate technological solutions that combine technical and economic aspects. The energized shield wire line technology (SWL), subject of this thesis, is in this context. This study aims at evaluating the viability of the SWL technology (three-phase scheme) installed on a 230 kV transmission line in the State of Rondônia. The analysis covers its technical, operational, and economic performance. The former aspect considers the performance of the grounding system regarding the ground resistance and step and touch voltages, analysis of voltage drop, voltage unbalance and the load capacity of the installation. The technical issue is deeply held after the analysis of the system operational performance in Rondônia based on the classification of outages considering a period greater than 180 months. The operational indices that result from this evaluation are compared to those corresponding to other technology alternatives in order to evaluate the viability of SWL technology. The analysis of the causes of interruptions reveals that lightning has a significant impact on the SWL performance. Thus, an extensive analysis is carried out regarding the effects of direct and indirect strokes on the SWL, including field measurements (soil resistivity and tower footing resistance) and laboratory tests (determination of the positive and negative critical flashover overvoltages of insulator strings). Simulations are performed using computer programs of proved validity (ATPDraw, ERM, and CDEGS) for the analysis of lightning overvoltages resulting from direct and indirect strokes and for the calculation of ground resistance. The effects of important parameters on the system lightning performance are investigated and the estimated and observed frequencies of interruptions are compared. The applied methodological procedure is described in detail, to allow the method to be used in other cases similar to the situations examined on this study. After a comparative analysis of the performance of the SWL with respect to other conventional alternatives, reference indices for the operational performance of SWL Technology are set and an economic analysis of the SWL technology in Rondônia is carried out.
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Universalização da energia elétrica através da tecnologia cabos pára-raios energizados (PRE) / Universalization of electrical energy services through the energized shield wire line technology (SWL)Ramos, José Ezequiel 29 April 2010 (has links)
A universalização da energia elétrica, como uma das principais políticas públicas de inclusão social, tem como desafio a escolha de alternativas tecnológicas capazes de conciliar os aspectos de viabilidade técnica e econômica. A Tecnologia cabos para-raios energizados (PRE), objeto de estudo desta tese, se insere neste contexto. Assim, este trabalho consiste na análise de viabilidade do PRE no esquema trifásico, cuja instalação é associada à linha de transmissão 230 kV do sistema de transmissão de Rondônia. São analisados os aspectos de seu desempenho técnico, operacional e econômico. No aspecto técnico é analisado o desempenho do sistema de aterramento quanto à resistência de terra, tensões de toque e de passo, além de análise da queda de tensão, desequilíbrio de tensão e capacidade de carregamento da instalação. A abordagem técnica é aprofundada após análise do desempenho operacional avaliado a partir da classificação das interrupções verificadas em mais de 180 meses de operação do Sistema PRE Rondônia. Em decorrência dessa avaliação, são obtidos índices operacionais de continuidade, analisados comparativamente em relação a outras alternativas tecnológicas, visando analisar a viabilidade da Tecnologia PRE. Uma das constatações resultantes da análise das causas das interrupções indica um elevado impacto das descargas atmosféricas no desempenho do PRE. Este aspecto é extensivamente analisado quanto aos efeitos das descargas diretas e indiretas sobre a instalação, partindo-se de medições de campo nos contrapesos das torres, medições de resistividade do solo e ensaios na cadeia de isoladores do PRE. Simulações são realizadas utilizando-se os programas computacionais ATPDraw, ERM e CDEGS para análise das tensões resultantes de descargas diretas, tensões induzidas por descargas indiretas e cálculo de resistência de terra, respectivamente. São investigados os efeitos de parâmetros importantes no desempenho do sistema frente a descargas atmosféricas e comparados os números de interrupções estimadas e verificadas em campo, partindo-se de um roteiro metodológico minuciosamente detalhado, a fim de permitir a repetição dos procedimentos em situações semelhantes às analisadas neste trabalho. Após uma análise comparativa do desempenho do sistema PRE em relação a outras alternativas convencionais, são estabelecidos índices de referência para o desempenho operacional da Tecnologia PRE e desenvolvida uma análise econômica da implantação dessa tecnologia em Rondônia. / As one of the major public policies of social inclusion, the universalization of electric energy services has as a challenge to choose appropriate technological solutions that combine technical and economic aspects. The energized shield wire line technology (SWL), subject of this thesis, is in this context. This study aims at evaluating the viability of the SWL technology (three-phase scheme) installed on a 230 kV transmission line in the State of Rondônia. The analysis covers its technical, operational, and economic performance. The former aspect considers the performance of the grounding system regarding the ground resistance and step and touch voltages, analysis of voltage drop, voltage unbalance and the load capacity of the installation. The technical issue is deeply held after the analysis of the system operational performance in Rondônia based on the classification of outages considering a period greater than 180 months. The operational indices that result from this evaluation are compared to those corresponding to other technology alternatives in order to evaluate the viability of SWL technology. The analysis of the causes of interruptions reveals that lightning has a significant impact on the SWL performance. Thus, an extensive analysis is carried out regarding the effects of direct and indirect strokes on the SWL, including field measurements (soil resistivity and tower footing resistance) and laboratory tests (determination of the positive and negative critical flashover overvoltages of insulator strings). Simulations are performed using computer programs of proved validity (ATPDraw, ERM, and CDEGS) for the analysis of lightning overvoltages resulting from direct and indirect strokes and for the calculation of ground resistance. The effects of important parameters on the system lightning performance are investigated and the estimated and observed frequencies of interruptions are compared. The applied methodological procedure is described in detail, to allow the method to be used in other cases similar to the situations examined on this study. After a comparative analysis of the performance of the SWL with respect to other conventional alternatives, reference indices for the operational performance of SWL Technology are set and an economic analysis of the SWL technology in Rondônia is carried out.
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