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Development of Wastewater Pipe Performance Index and Performance Prediction ModelAngkasuwansiri, Thiti 11 June 2013 (has links)
Water plays a critical role in every aspect of civilization: agriculture, industry, economy, environment, recreation, transportation, culture, and health. Much of America's drinking water and wastewater infrastructure; however, is old and deteriorating. A crisis looms as demands on these systems increase. The costs associated with renewal of these aging systems are staggering. There is a critical disconnect between the methodological remedies for infrastructure renewal problems and the current sequential or isolated manner of renewal analysis and execution. This points to the need for a holistic systems perspective to address the renewal problem. Therefore, new tools are needed to provide support for wastewater infrastructure decisions. Such decisions are necessary to sustain economic growth, environmental quality, and improved societal benefits. Accurate prediction of wastewater pipe structural and functional deterioration plays an essential role in asset management and capital improvement planning. The key to implementing an asset management strategy is a comprehensive understanding of asset condition, performance, and risk profile.
The primary objective of this research is therefore to develop protocols and methods for evaluating the wastewater pipe performance. This research presents the life cycle of wastewater pipeline identifying the causes of pipe failure in different phases including design, manufacture, construction, operation and maintenance, and repair/rehabilitation/replacement. Various modes and mechanisms of pipe failure in wastewater pipes were identified for different pipe material which completed with results from extensive literature reviews, and interviews with utilities and pipe associations. After reviewing all relevant reports and utility databases, a set of standard pipe parameter list (data structure) and a pipe data collection methodology were developed. These parameters includes physical/structural, operational/functional, environmental and other parameters, for not only the pipe, but also the entire pipe system. This research presents a development of a performance index for wastewater pipes. The performance index evaluates each parameter and combines them mathematically through a weighted summation and a fuzzy inference system that reflects the importance of the various factors. The performance index were evaluated based on artificial data and field data to ensure that the index could be implemented to real scenarios. Developing a performance index led to the development of a probabilistic performance prediction model for wastewater pipes. A framework would enable effective and systematic wastewater pipe performance evaluation and prediction in asset management programs. / Ph. D.
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The impact of Chinese airport infrastructure on airline pollutant emissions: A hybrid stochastic-neural network approach based on utility functionsCui, Q., Antunes, J., Wanke, P., Tan, Yong, Roubaud, D., Jabbour, C.J.C. 18 January 2024 (has links)
Yes / With China being the world’s largest emitter of greenhouse gases and its aviation sector burgeoning, the environmental performance of Chinese airlines has global significance. Amidst rising demands for eco-friendly
practices from both customers and regulators, the interplay between airport infrastructure and environmental
performance becomes pivotal. This research offers an innovative methodology to gauge the environmental
performance of Chinese airlines, emphasizing the distance traveled between airports using weighted additive
utility functions. Leveraging neural networks, the study investigates the impact of various airport infrastructural
characteristics on environmental performance. Noteworthy findings indicate that ground control measures,
automatic information services at origin airports, surface concrete on runways at both ends, and a centerline
lighting system in destination airports positively influence environmental performance. In contrast, longer and
wider runways at origin airports, increased distances to control towers, and asphalt runways at destination
airports adversely affect it. These insights not only underscore the importance of strategic infrastructure enhancements for reducing carbon footprints but also hold profound policy implications. As global climate change
remains at the forefront, fostering sustainable airport infrastructure in China can significantly contribute to
worldwide mitigation efforts. / The full-text of this article will be released for public view at the end of the publisher embargo on 18 Jan 2025.
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Dolly with hinged drawbar / Dolly med ledad dragstångOlsson, Emil, Skönvall, Henrik January 2018 (has links)
Volvo trucks are involved in a project with vehicle combinations longer than 25.25 meters and/or with a weight of more than 64 tons. Those combinations are called high capacity transport (HCT). Some of the vehicle combinations are now driven with exemptions for the coupling equipment. The exemption is needed because according to a standard the theoretical transmitted forces between the dolly and the truck exceed the value that the coupling components have been certified for. The theoretical transmitted forces are called performance indexes. This limits the development but the exception could be avoided by using a hinged drawbar on the dolly. This thesis aims to investigate what needs to be done in order to introduce dolly with hinged drawbar in longer and heavier vehicle combinations. A literature study and interviews were conducted to find problems that could be expected when using hinged drawbar on dolly and to investigate how the performance indexes for a specific vehicle combination should be calculated. Thereafter a dolly was put together through a product development process. Then concepts to solve a problem that was noticed through the literature study were developed. The concepts were sketched, evaluated in a matrix and thereafter the winning concept was modelled in detail in computer aided design (CAD). According to the traffic definition in Sweden a dolly with hinged drawbar is violating the law. It defines a dolly as a module with rigid drawbar. On the other hand, the European Union defining a dolly as a trailer with fifth- wheel made to convert a semi-trailer into a full trailer. They don’t mention anything that contradicts to the usage of hinged drawbar. So the Swedish definition of a dolly needs to be challenged. Simulations have shown that the braking performance will be worse when using a dolly with hinged drawbar compared to using a dolly with rigid drawbar. Therefore concepts to improve the braking performance of the dolly have been developed. The concept was to look the fifthwheel from pivoting around a horizontal axle perpendicular to the driving direction. By doing so the dolly and semi-trailer will become more like a full trailer and that would better the braking performance. Through interviews and literature study it was noticed that the high performance indexes were calculated in an incorrect way. The highest forces are generated through interaction forces which are only affected by the vehicles closest to the coupling components. Therefore a calculation model need to be modified for this. Three calculation models were tested on the vehicle-combination. Two of these generated performance indexes that were reasonable. The calculation models were ISO-combination 3 and a model developed by Sweatman (1980). These two calculation models are modified for vehicle combinations that includes three vehicles. / Volvo lastvagnar ingår i ett forskningsprojekt med lastbilskombinationer som är längre än 25,25 meter och/eller väger mer än 64 ton. Ett sådant fordon kallas högkapacitetstransport (HCT). Idag körs vissa av dessa fordon med dispenser för kopplingsutrustningen. Detta då de teoretiska överförda krafterna mellan lastbil och dolly enligt en standard får värden som är högre än vad kopplingsutrustningen är certifierad med. De teoretiska överförda krafterna benämns som prestandaindex. Denna dispens skulle kunna undvikas genom att använda en ledad dragstång på dollyn. Detta examensarbete syftar till att undersöka vad som behöver göras för att introducera dolly med ledad dragstång i längre och tyngre fordonskombinationer. En litteraturundersökning samt intervjuer genomfördes för att upptäcka problem som kan uppstå vid användande av dolly med ledad dragstång. Även en undersökning gällande hur prestandaindex ska beräknas på rätt sätt genomfördes. Därefter konstruerades en dolly genom en produktutvecklingsprocess. Koncept för att lösa ett problem som noterades under litteraturundersökningen utvecklades. Koncepten skissades och blev sedan utvärderade genom en matris. Det vinnande konceptet konstruerades i CAD. Från litteraturstudien visade det sig att det finns en motstridighet i den svenska definitionen gällande användandet av ledad dragstång på dolly. I Sverige definieras dolly som en kärra. En kärra definieras som en modul med stel dragstång. Däremot definierar EU dolly som en trailer som konverterar en semi-trailer till en full trailer. Där nämns ingenting som kan stoppa användandet av dolly med ledad dragstång. Därför borde den svenska definitionen utmanas. En dolly med ledad dragstång förväntas ha sämre bromsprestanda än en vanlig dolly. Koncept utvecklades för att förbättra bromsprestandan på dollyn. Konceptet som vann var att låsa vändskivan från att vridas runt en horisontell axel vinkelrätt till åkriktningen. På så viss blir kombinationen dolly, semi-trailer mer som en full trailer vilket skulle innebära en bättre bromsprestanda. Från intervjuer med kunniga personer och från litteraturstudien framkom det att de höga prestanda indexen var felaktigt beräknade. Det blev även känt att de största krafterna genereras genom interaktionskrafter som endast påverkas av de närmaste fordonens vikt. Tre olika beräkningsmodeller testades där två utav dem gav värden som kan anses vara rimliga. Beräkningsmodellerna var ISO-kombination 3 och en modell utvecklad av Sweatman (1980). Dessa två är anpassad för kombinationer som innehåller 3 fordon.
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Transmission System Restoration Strategies in Real TimeJanuary 2010 (has links)
abstract: After a power system blackout, system restoration is the most important task for the operators. Most power systems rely on an off&ndashline; restoration plan and the experience of operators to select scenarios for the black start path. Using an off&ndashline; designed restoration plan based on past experience may not be the most reliable approach under changing network configurations and loading levels. Hence, an objective restoration path selection procedure, including the option to check constraints, may be more responsive in providing directed guidance to the operators to identify the optimal transmission path to deliver power to other power plants or to pick up load as needed. After the system is subjected to a blackout, parallel restoration is an efficient way to speed up the restoration process. For a large scale power system, this system sectionalizing problem is quite complicated when considering black&ndashstart; constraints, generation/load balance constraints and voltage constraints. This dissertation presents an ordered binary decision diagram (OBDD) &ndashbased; system sectionalizing method, by which the splitting points can be quickly found. The simulation results on the IEEE 39 and 118&ndashbus; system show that the method can successfully split the system into subsystems satisfying black&ndashstart; constraints, generation/load balance constraints and voltage constraints. A power transfer distribution factor (PTDF)&ndashbased; approach will be described in this dissertation to check constraints while restoring the system. Two types of restoration performance indices are utilized considering all possible restoration paths, which are then ranked according to their expected performance characteristics as reflected by the restoration performance index. PTDFs and weighting factors are used to determine the ordered list of restoration paths, which can enable the load to be picked up by lightly loaded lines or relieve stress on heavily loaded lines. A transmission path agent can then be formulated by performing the automatic path selection under different system operating conditions. The proposed restoration strategy is tested on the IEEE&ndash39; bus system and on the Western region of the Entergy system. The testing results reveal that the proposed strategy can be used in real time. / Dissertation/Thesis / Ph.D. Electrical Engineering 2010
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Metodologia para o monitoramento de sistemas de controle na indústria químicaSouza, Davi Leonardo de 28 November 2011 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Control systems monitoring relates to ability to supervise the industrial plants operation,
evaluating the controller performance by oscillation detection, disturbances,
faults in sensors, valve stiction and diagnosing possible causes of problems that may
degrade the productive capacity, managing alarms and providing possible strategies
to act or even improve the eciency of operation. Control Process Monitoring
(CPM) and Control Process Assessment (CPA) technologies are essential for maintaining
the ecient during operation of industrial processes. This work presents a
systematic method for monitoring of control systems in chemical industry, using a
performance manager. This way it was investigated control systems using the performance
index concept to quantify the degradation of controller's eciency, that is
a tool to evaluate the behavior in industrial operation context. Performance index
supplies the idea of as the control system is distant of best control idealized with
same structure. Due the characteristics of reference behavior, that does not depend
on the structure of control used, it can be evaluated controllers of several types and
under several situations. This index was obtained by design of reference, using the
factorization with interactor matrix generalized. Discover abnormalities in control
systems is very important and complicated. In addition, was evaluated procedures
subject to presence of oscillations, using an extension of the Karhunem-Loeve
method and periodogramas. It was also evaluated, processes with valves stiction
using the Yamashita method and faults in sensors and systems subjected to disturbances,
using the principal components analysis (PCA) with T2 and Q statistics,
with objective of detecting, isolating and diagnosing possible cause of control systems
deterioration. / Monitorar sistemas de controle relaciona-se à capacidade de supervisionar de maneira
ampla a operação de plantas industriais, avaliando o desempenho de controladores,
detectando oscilações, perturbações, falhas em sensores, emperramento de
válvulas de controle e diagnosticando as possíveis causas de problemas que possam
degradar a capacidade produtiva, gerenciando alarmes e fornecendo possíveis
estratégias de como atuar para manter, ou até mesmo, aprimorar a eficiência da
operação. O monitoramento contínuo do desempenho de sistemas de controle (Control
Process Monitoring - CPM) e a avaliação do desempenho de sistemas de controle
(Control Process Assessment - CPA) são tecnologias essenciais para a manutenção
da eficiência durante a operação de processos industriais. Neste contexto, este trabalho
apresenta uma sistemática para o monitoramento de sistemas de controle na
indústria química, através de um gerenciador de desempenho proposto. Desta forma
foi investigado sistemas de controle utilizando o conceito de índice de desempenho
para quantificar a degradação da eficiência do controlador, tratando-se de uma ferramenta
para a sua avaliação durante a operação industrial. O índice de desempenho
fornece a ideia do quanto o controle corrente do sistema esta distante do melhor
controle idealizado com mesma estrutura. Devido as características do comportamento
de referência, que independe da estrutura de controle utilizada, pode-se
avaliar controladores de diversos tipos e sob varias situações. Este índice foi obtido
através do projeto da referência, utilizando fatoração de modelos lineares através
da matriz de interação generalizada. Descobrir anormalidades constitui-se uma tarefa
muito importante e complicada. Desta forma, avaliou-se processos sujeitos à
presença de oscilações, utilizando uma extensão do método de Karhunem-Loéve e
periodogramas. Avaliou-se também, processos com emperramento de válvulas de
controle através do método de Yamashita e falhas em sensores e sistemas submetidos
à perturbações, utilizando a analise dos componentes principais (PCA) e as
estatísticas T2 e Q, com o objetivo de detectar, isolar e diagnosticar a possível causa
da degradação dos sistemas de controle analisados. / Doutor em Engenharia Química
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Estudo para classificação de contingencias sob o aspecto da estabilidade de tensão / Contingency ranking for voltage stabilityDester, Mauricio 22 August 2006 (has links)
Orientador: Carlos Alberto de Castro Junior / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-07T06:07:11Z (GMT). No. of bitstreams: 1
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Previous issue date: 2006 / Resumo: O objetivo deste trabalho é propor um método que permita, de forma rápida e segura, estabelecer uma lista de contingências ordenada por severidade considerando a óptica da estabilidade de tensão. Em linhas gerais, o procedimento consiste em obter o
estado da rede após a simulação de uma determinada contingência e calcular o índice de
performance correspondente à mesma. Estes passos devem ser repetidos para todos os
ramos da rede. Ao final tem-se um índice associado a cada contingência. Para a obtenção
da lista ordenada por severidade, classificam-se as contingências considerando como fator de ordenação o valor do índice de performance calculado para cada uma delas. De posse desta lista, pode-se lançar mão de ferramentas que permitam uma análise mais detalhada para o grupo contingências com maior severidade e a tomada de ações no sentido de minimizar as conseqüências causadas por estas contingências. Este método pode ser utilizado como suporte à operação em tempo real, pois permite a seleção das contingências mais severas, de forma rápida, para então posteriormente realizar uma análise mais detalhada das mesmas. Não há, portanto, a necessidade da análise detalhada de todas as contingências da rede, o que permite uma economia de tempo, esforço humano e computacional, recursos estes de fundamental importância considerando a operação em tempo real / Abstract: The aim of this work is to propose a fast and reliable method to rank a list of
contingencies ordered by severity under the voltage stability point of view. The basic steps of the method consist of computing the system's post-contingency state and computing the respective performance index. These steps must be repeted for contingencies associated to all system branches. So an ordered contingency list is built considering the performance index of each contingency as a merit factor. With this list it is possible to pick the most severe contingencies and submit them to conventional tools that allow a more complete analysis and appropriate decisions to avoid operating system in insecure conditions if one of the severe contingencies occurs. It is possible to use this method as a real time tool due to its efficiency. Little computational effort is made to get the ordered contingency list and it is possible to focus the human and computational effort on the most severe contingencies. The real time operation requires efficient decision-making procedures and this method brings up the possibility of saving time since it is no longer necessary to analize all system contingencies to find out the most severe one. It suffices to analize the top-ranked contingencies captured by the proposed method / Mestrado / Energia Eletrica / Mestre em Engenharia Elétrica
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Estresses abióticos em híbridos de canola: Efeito do alagamento e de baixas temperaturas / Abiotic stress in canola hybrids: Effect of flooding and low temperaturesPERBONI, Anelise Tessari 14 February 2011 (has links)
Made available in DSpace on 2014-08-20T13:59:11Z (GMT). No. of bitstreams: 1
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Previous issue date: 2011-02-14 / Oilseed rape (Brassica napus L.) belongs to the family Brassicaceae and constitutes the
third most produced oilseed in the world, surpassed only by soybean and palm.
Flooding of soil and low temperatures can cause alterations in cellular metabolism
and impair plant growth, generating a stress condition. Two experiments were
conducted using the canola hybrid Hyola 43, Hyola 401, Hyola 420 and Hyola 432.
The first was conducted in greenhouse where 10 plants of each hybrid were
subjected to stress by flooding for a period of six days. Were evaluated parameters
and differences in the kinetics of emission of chlorophyll fluorescence, chlorophyll
content, leaf area and dry weight of shoot and root. The flooding caused a reduction
of leaf area, root dry mass and root dry mass/shoot dry mass ratio of all hybrids
studied. In relation to chlorophyll fluorescence were identified differences in
parameters related to specific flows that have undergone changes as a function of
stress the latter being more pronounced for Hyola 432. The performace
photosynthetic index (PIABS and PIABS,total) showed a decrease after 6 days of the
experiment except for hybrid Hyola 420. The analysis of the kinetics of chlorophyll a
fluorescence transient showed differential effects of stress application in different
sites of photosynthetic apparatus, and these effects were less pronounced in the
plants of hybrid Hyola 420. In the second experiment, canola plants were grown in a
greenhouse where stress by low temperatures was driven in the Laboratory of Plant
Metabolism. Ten plants of each hybrid were placed in a growth chamber the absence
of light for different periods of low temperatures: 1 and 4 hours at 0oC and 1, 4 and
15 hours at 4oC. Were evaluated parameters and differences in the kinetics of
emission of chlorophyll a fluorescence. The hybrids showed the same behavior in
relation to chlorophyll a fluorescence in response to stress by low temperatures. In
general, the parameters of chlorophyll fluorescence related to the activity of the PSI
were the most affected, and the increase of these parameters resulted in higher
values of the PIABS,total. The analysis of the kinetics of chlorophyll a fluorescence
transient showed temperature effects, mainly at the J point which reflects the
accumulation of reduced plastoquinone (QA
-) and the I-P phase reflecting the
reduction of end electron acceptors at the PSI acceptor side, ie, ferredoxin (Fd)
NADP and other intermediaries. We conclude that the plants of the hibrid Hyola 420
were less affected by flooding showing that this hybrid can be considered less
sensitive to stress compared to other hybrids. The parameters that involve the activity
of the FSI and the variable fluorescence transient at the J point were more
responsive to stress conditions imposed by low temperatures. / A canola (Brassica napus L.) pertence à família das Brassicaceae e constitui-se na
terceira oleaginosa mais produzida no mundo, superada apenas pela soja e pela
palma. O alagamento do solo e as baixas temperaturas podem promover alterações
no metabolismo celular e prejudicar o crescimento das plantas, gerando uma
condição de estresse. Foram desenvolvidos dois experimentos utilizando os híbridos
de canola Hyola 43, Hyola 401, Hyola 420 e Hyola 432. O primeiro foi conduzido em
casa de vegetação, onde 10 plantas de cada híbrido foram submetidas a estresse
por alagamento por um período de seis dias. Foram avaliados os parâmetros e as
diferenças na cinética de emissão da fluorescência da clorofila, teor de clorofila, área
foliar e massa seca da parte aérea e raiz. O alagamento promoveu redução da área
foliar, massa seca de raízes e relação massa seca de raiz/massa seca parte aérea
de todos híbridos estudados. Em relação a fluorescência da clorofila foram
identificadas diferenças nos parâmetros relacionados aos fluxos específicos que
sofreram variação em função do estresse sendo esta mais acentuada para Hyola
432. Os índices de performace fotossintéticos (PIABS e PIABS,total) apresentaram
decréscimo ao final de 6 dias de experimento exceto para o híbrido Hyola 420. A
análise da cinética da fluorescência transiente da clorofila a mostrou efeitos
diferenciais da aplicação do estresse nos diferentes locais da maquinaria
fotossintética, sendo estes efeitos menos pronunciados nas plantas do híbrido Hyola
420. No segundo experimento as plantas de canola foram cultivadas em casa de
vegetação sendo o estresse por baixas temperaturas conduzido no Laboratório de
Metabolismo Vegetal. Dez plantas de cada híbrido foram acondicionadas em câmara
de crescimento com ausência de luz por períodos distintos de baixas temperaturas:
1 e 4 horas a 0oC e 1, 4 e 15 horas a 4oC. Avaliaram-se os parâmetros e as
diferenças na cinética de emissão da fluorescência da clorofila a. Os híbridos
apresentaram o mesmo comportamento em relação à fluorescência da clorofila em
resposta ao estresse por baixas temperaturas. Em geral, os parâmetros da
fluorescência da clorofila relacionados à atividade do fotossistema I foram os mais
afetados, sendo que o aumento destes parâmetros resultou em maiores valores de
PIABS,total. A análise da cinética da fluorescência transiente da clorofila a revelou
efeitos da temperatura principalmente no ponto J o qual reflete o acúmulo de
plastoquinona A reduzida (QA
-) e na fase I-P que reflete a redução dos aceptores de
elétrons finais do lado aceptor do FSI, ou seja, ferredoxina (Fd), outros
intermediários e NADP. Conclui-se que as plantas do híbrido Hyola 420 foram
menos afetadas pelas condições de alagamento demonstrando que tal híbrido pode
ser considerado menos sensível a determinado estresse em relação aos demais
híbridos testados. Os parâmetros que envolvem a atividade do FSI bem como a
5
fluorescência variável transiente no ponto J foram mais responsivos às condições
impostas pelo estresse por baixas temperaturas.
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Energy storage in the future smart grid. An investigation of pricing strategies and dynamic load levelling for efficient integration of domestic energy storage within a virtual power plant and its evaluation using a genetic algorithm optimization platformOkpako, Oghenovo January 2019 (has links)
One feature that is hoped for in the smart grid is the participation of energy prosumers in
a power market through demand response program. In this work, we consider a third-party
virtual power plant (VPP) that has “real-time” control over a number of prosumers’
storage units within an envisaged free market. Typically, a VPP with domestic energy
storage will involve a bidirectional flow of energy, where energy can either flow from the
grid to the prosumers’ battery or from the prosumers’ battery to the grid. Such a system
requires prices to be set correctly in order to meet the market objectives of all the VPP
stakeholders (VPP Aggregator, prosumers, and grid).
Previous work has shown how VPPs could operate, and the benefits of using energy
storage, coupled with pricing, in terms of reducing energy cost for stakeholders and
providing the grid with its required load shape. The published work either assumes prices
or costs or then optimises for least cost within the grid parameters i.e. losses, voltage
limits, etc. However, the setting of prices in such a way that energy can be traded among
VPP stakeholders that satisfies all stakeholders’ objectives has not been fully explored in
the literature, particularly with real-time VPP aggregators.
In this thesis, we present novel strategies for evaluating and setting the prices of a
community VPP with domestic storage based on the bidirectional flow of energy through
the VPP aggregator between the grid and the prosumers that mutually meet all VPP
stakeholders’ objectives. This showed that depending on pricing and the VPP objectives,
demand-side management could be attractive. However, the effect on the grid in terms of
the load was not what was desired. A new performance index called the “Cumulative
Performance Index” CPI is proposed to measure the VPP’s performance. Using the CPI,
it was possible to compare and contrast between the VPP technical performance and its
business case for stakeholders. Optimizing with respect to the grid’s requirement for DSM
from the VPP, it was possible to achieve a CPI of 100%. This work was implemented
using a novel approach on a genetic algorithm platform. / Niger Delta Development Commission of Nigeria
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"Índices de carga e desempenho em ambientes paralelos/distribuídos - modelagem e métricas" / Load and Performance Index for Parallel/Distributed System - Modelling and MetricsBranco, Kalinka Regina Lucas Jaquie Castelo 15 December 2004 (has links)
Esta tese aborda o problema de obtenção de um índice de carga ou de desempenho adequado para utilização no escalonamento de processos em sistemas computacionais heterogêneos paralelos/distribuídos. Uma ampla revisão bibliográfica com a correspondente análise crítica é apresentada. Essa revisão é a base para a comparação das métricas existentes para a avaliação do grau de heterogeneidade/homogeneidade dos sistemas computacionais. Uma nova métrica é proposta neste trabalho, removendo as restrições identificadas no estudo comparativo realizado. Resultados de aplicações dessa nova métrica são apresentados e discutidos. Esta tese propõe também o conceito de heterogeneidade/homogeneidade temporal que pode ser utilizado para futuros aprimoramentos de políticas de escalonamento empregadas em plataformas computacionais heterogêneas paralelas/distribuídas. Um novo índice de desempenho (Vector for Index of Performance - VIP), generalizando o conceito de índice de carga, é proposto com base em uma métrica Euclidiana. Esse novo índice é aplicado na implementação de uma política de escalonamento e amplamente testado através de modelagem e simulação. Os resultados obtidos são apresentados e analisados estatisticamente. É demonstrado que o novo índice leva a bons resultados de modo geral e é apresentado um mapeamento mostrando as vantagens e desvantagens de sua adoção quando comparado às métricas tradicionais. / This thesis approaches the problem of evaluating an adequate load index or a performance index, for using in process scheduling in heterogeneous parallel/distributed computing systems. A wide literature review with the corresponding critical analysis is presented. This review is the base for the comparison of the existing metrics for the evaluation of the computing systems homogeneity/heterogeneity degree. A new metric is proposed in this work, removing the restrictions identified during the comparative study realized. Results from the application of the new metric are presented and discussed. This thesis also proposes the concept of temporal heterogeneity/homogeneity that can be used for future improvements in scheduling polices for parallel/distributed heterogeneous computing platforms. A new performance index (Vector for Index of Performance - VIP), generalizing the concept of load index, is proposed based on an Euclidean metric. This new index is applied to the implementation of a scheduling police and widely tested through modeling and simulation. The results obtained are presented and statistically analyzed. It is shown that the new index reaches good results in general and it is also presented a mapping showing the advantages and disadvantages of its adoption when compared with the traditional metrics.
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"Índices de carga e desempenho em ambientes paralelos/distribuídos - modelagem e métricas" / Load and Performance Index for Parallel/Distributed System - Modelling and MetricsKalinka Regina Lucas Jaquie Castelo Branco 15 December 2004 (has links)
Esta tese aborda o problema de obtenção de um índice de carga ou de desempenho adequado para utilização no escalonamento de processos em sistemas computacionais heterogêneos paralelos/distribuídos. Uma ampla revisão bibliográfica com a correspondente análise crítica é apresentada. Essa revisão é a base para a comparação das métricas existentes para a avaliação do grau de heterogeneidade/homogeneidade dos sistemas computacionais. Uma nova métrica é proposta neste trabalho, removendo as restrições identificadas no estudo comparativo realizado. Resultados de aplicações dessa nova métrica são apresentados e discutidos. Esta tese propõe também o conceito de heterogeneidade/homogeneidade temporal que pode ser utilizado para futuros aprimoramentos de políticas de escalonamento empregadas em plataformas computacionais heterogêneas paralelas/distribuídas. Um novo índice de desempenho (Vector for Index of Performance - VIP), generalizando o conceito de índice de carga, é proposto com base em uma métrica Euclidiana. Esse novo índice é aplicado na implementação de uma política de escalonamento e amplamente testado através de modelagem e simulação. Os resultados obtidos são apresentados e analisados estatisticamente. É demonstrado que o novo índice leva a bons resultados de modo geral e é apresentado um mapeamento mostrando as vantagens e desvantagens de sua adoção quando comparado às métricas tradicionais. / This thesis approaches the problem of evaluating an adequate load index or a performance index, for using in process scheduling in heterogeneous parallel/distributed computing systems. A wide literature review with the corresponding critical analysis is presented. This review is the base for the comparison of the existing metrics for the evaluation of the computing systems homogeneity/heterogeneity degree. A new metric is proposed in this work, removing the restrictions identified during the comparative study realized. Results from the application of the new metric are presented and discussed. This thesis also proposes the concept of temporal heterogeneity/homogeneity that can be used for future improvements in scheduling polices for parallel/distributed heterogeneous computing platforms. A new performance index (Vector for Index of Performance - VIP), generalizing the concept of load index, is proposed based on an Euclidean metric. This new index is applied to the implementation of a scheduling police and widely tested through modeling and simulation. The results obtained are presented and statistically analyzed. It is shown that the new index reaches good results in general and it is also presented a mapping showing the advantages and disadvantages of its adoption when compared with the traditional metrics.
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