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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Avaliação e controle do trabalho educativo: contradições entre meios e fins no monitoramento da qualidade da educação / Evaluation and control of educative work: contradictions between ways and purposes in the monitoring of the education\'s quality

Abelardo Bento Araujo 11 November 2016 (has links)
Esta tese apresenta uma pesquisa que teve como objetivo geral analisar em que medida o monitoramento da qualidade da educação básica favorece o alcance dos fins da educação, compreendida essa como ação pedagógica e como processo de trabalho. A partir de um referencial analítico sobre a natureza do trabalho educativo e sobre os fins da educação, questionou-se o monitoramento como meio eleito pelo Estado para elevar a qualidade da educação. O foco específico foi o ensino fundamental, etapa da educação básica que se identifica plenamente com o conceito de educação adotado, ou seja, educação como apropriação da cultura humana, que visa à humanização plena do homem. Para compreender o fenômeno no âmbito da cotidianidade escolar, a pesquisa qualitativa buscou compreender as complexas relações que o envolvem, priorizando os acontecimentos, antes da busca de causas. Utilizou-se de pesquisas bibliográficas e documentais, assim como de perspectivas da etnografia para interrogar os sujeitos (professores, coordenadores pedagógicos e diretora da escola) na pesquisa de campo. A partir disso, foi possível verificar que o caminho adotado na política educacional brasileira de monitoramento da qualidade e, particularmente, em Minas Gerais vale-se de mecanismos da gerência tal como concebida por Harry Braverman (1987), ou seja, como controle do trabalho alheio. Nos moldes em que essa política foi formulada ao longo dos primeiros quinze anos do século XXI, ela foi apoiada num conceito distorcido do que seja a produtividade da escola, que a leva a identificar como produto do trabalho educativo um conhecimento supostamente tangível por meio de testes. A política intensifica o trabalho na escola, sem conseguir oferecer mais e melhor educação de fato. O monitoramento da qualidade da educação mineira negligencia que o fim da educação é o próprio homem e que esse fato é que deveria determinar a escolha dos meios, das estratégias. Isso conduz, ainda, à negligência de que aluno e professor são os trabalhadores que despendem sua força de trabalho na realização do produto do trabalho educativo e de que, portanto, eles não podem ter sua condição de sujeito negada. Leva, também, à confusão entre testagem de objetos e avaliação de sujeitos, bem como à distorção dos próprios fins da educação, na medida em que impele as escolas à redução curricular, por meio do treinamento dos alunos para a realização de testes. As interferências sobre a escola encerram a determinação do conteúdo e da forma do trabalho educativo. Ainda que a escola preserve espaços de autonomia, o monitoramento tem burocratizado a atividade educativa, porque aplica a esta uma lógica e uma forma extraídas de outros processos (como a produção de mercadorias). / This thesis presents a study that aimed to examine to what extent the monitoring of the quality of basic education promotes the achievement of educational purposes, including education as a pedagogical action and as a working process. From an analytical framework on the nature of the educational work and about the purposes of education, this work called into question the monitoring as a means chosen by the state to improve the quality of education. The specific focus was the primary school stage of education that fully identifies with the concept of education adopted, i.e. education as the appropriation of human culture, which aims at man\'s full humanization. To understand the phenomenon within the school daily life, qualitative research aimed at understanding the complex relationships that involve prioritizing the events before the search for causes. Bibliographic and documentary research were used, as well as perspectives of ethnography to examine the subject (teachers, pedagogical coordinators and school director) in the field research. From this, it was possible to verify that the path adopted in the Brazilian educational policy of quality monitoring-and particularly in Minas Gerais valley-betakes mechanisms of management as conceived by Harry Braverman (1987), this is as a control of other peoples labor. The way in which this policy was formulated over the first fifteen years of the century was supported by a distorted concept of school productivity, which leads to identify the knowledge supposedly measurable by testing as a educational work product. The policy intensifies work in school, unable to offer more and better education fact. The quality monitoring of education in Minas Gerais neglects the fact that the purposes of education is the human being itself and that this is what should determine the choice of means, strategies. This leads also to the negligence of that student and teacher are the workers who spend their workforce in the realization of the educational work product and that therefore they can not have denied their subjecthood. It also leads to the confusion between testing objects and evaluation of subjects as well as to the distortion of the own purposes of education in that schools are compelled to reduce curricula by means of training of students for exams. Interference in schools encloses determining the content and form of educational work. Although schools still preserves spaces of autonomy, monitoring has bureaucratized educational activity, since it applies to the latter the rationale and the form extracted from other processes (such as the production of goods).
92

Desenvolvimento de apalpador de contato elétrico (\"touch trigger probe\") para atuação no processo de torneamento / Devefopment of a low cost touch trigger probe for CNC lathes

Marcelo Del Guerra 21 September 2004 (has links)
A utilização dos apalpadores acoplados a máquinas CNC se tornou uma realidade muito comum no mundo atual, principalmente devido à diminuição do tempo de preparação e possibilidades de realização de medições na própria máquina-ferramenta. Porém, ainda existem algumas barreiras a se transpor, como por exemplo, a dificuldade de programação, custo relativamente elevado e pouca literatura que trata exclusivamente a respeito da utilização dos apalpadores para medição nas máquinas-ferramentas. Nesse trabalho é realizada uma revisão bibliográfica sobre o uso dos apalpadores em ambiente industrial, discutindo-se as tecnologias utilizadas na geração do sinal de \"trigger\" e é proposto um novo modelo de apalpador de contato elétrico, de baixo custo, desenvolvido especialmente para atender as necessidades de medições em tornos CNC. Os testes em laboratório revelaram que a repetibilidade do protótipo construído foi de 0,003 mm dentro de uma confiabilidade de mais ou menos 3 \'sigma\' ou 99,73%. Concluiu-se que tais características são altamente compatíveis com os requisitos necessários para a maioria dos processos de torneamento. / The use of touch trigger probes attached to CNC machines has become a world standard, especially due the reduction of setup time and the ability to promote work piece measurements on machine. However, some barriers like measurement routines programming difficulties, high costs of these equipments and the low number of technical literature about this subject, still need to be transposed. This work presents a review on the applications of touch trigger probes on companies shop floor, discussing the nowadays technologies used to generate the trigger signal. A new touch trigger probe model based on a simple electrical contact is specially developed to provide the measuring characteristics required for Lathes, with the needed characteristics and low cost. The tests of the probe developed in the laboratory shown a repeatability of 0,003 mm (more and less 3 \'sigma\' or 99,73%). Those characteristics are high compatible with the most needs of the industry.
93

Elkvalitetsövervakning i låg- och mellanspänningsnät / Power quality monitoring in low- and medium-voltage networks

Roger, Helleblad January 2021 (has links)
Krav på överföringen av el ställs i föreskrifter och standarder för att hålla störande elkvalitetsparametrar inom godtagbara nivåer i nätet. På senare år har användandet av elnätet förändrats med nya belastningar, distribuerad generering och en ökande mängd kraftelektronik. Detta bidrar till ett ökat behov att utföra kontinuerlig övervakning av parametrar som kan orsaka problem för kund och nätägare. I samband med installationen av de nya ”smarta elmätarna” hos kunder finns möjligheten att få utökad elkvalitetsövervakning i stora delar av nätet. Till följd av detta har Geab valt att se över sin elkvalitetsövervakning. I denna rapport ligger fokus på vilka parametrar som ska övervakas, var i nätet de ska övervakas och hur man kan bedriva detta effektivt med en bra täckning av nätet. Syftet med denna övervakning är primärt att verifiera att nätet uppfyller standard. Men andra fördelar finns, bland annat kan åtgärder vidtas i ett område innan gränsvärden överskrids. Det går även att använda utrustningen för störningsanalys. I denna rapport sammanställs vilka parametrar som ska övervakas och vilka krav som gäller för mätutrustning vid mätning av elkvalitet enligt standard och föreskrift. Förslag ges även på var och hur mätning kan utföras. Sju mätsystem har jämförts utifrån dessa parametrar. Baserat på resultatet rekommenderas att fasta mätare installeras i fördelningsstationer på nedsidan av mellanspänningstransformatorn, i kombination med smarta elmätare i nätstation och i anslutningspunkt mot kund i lågspänningsnät. Detta för att få en kostnadseffektiv täckning och hantering av elkvalitetsövervakning i nätet. På grund av det stora antalet mätinstrument bör övervakning av elkvaliteten ske med hjälp av gränsvärdesövervakning och automatiskt genererade rapporter. Detta minskar hanteringstid för personal då portabla mätare inte behöver monteras men även då systemet behandlar den insamlade informationen på egen hand. Eftersom gränsvärdesövervakning kan missa vissa avvikelser bör även stickprov utföras för att verifiera den automatiska övervakningen. / Requirements for the transmission of electricity are set in regulations and standards to keep disruptive power quality parameters in the grid within acceptable levels. In recent years, the use of the electrical grid has changed with new loads, distributed generation, and an increasing amount of power electronics. This contributes to an increased need to perform continuous monitoring of parameters that can cause problems for customers and network owners. With the installation of the new ”smart meters” at customers connection point, there is the possibility of having extended power quality monitoring in large parts of the network. As a result, Geab has chosen to review its power quality monitoring. This report focuses on which parameters are to be monitored, where to monitor and how this can be done effectively with good coverage of the network. The purpose of this monitoring is primarily to verify that the network meets the requirements. But there are other advantages, for example, steps can be taken before a limit value is exceeded in an area. It is also possible to use the equipment for analyzing disturbances. This report summarizes which parameters to monitor and which requirements apply to measuring equipment when measuring power quality in accordance with standards and regulations. Suggestions are also given on where and how measurement can be performed. Seven measurement systems have been compared based on these parameters. Based on the results, the recommendation is that fixed meters be installed in substations on the medium voltage side of the transformer, in combination with "smart meters" in distribution substations and at the connection point to the customer in the low voltage network. This will result in cost-effective coverage and management of power quality monitoring in the network. Due to a large number of measuring instruments, monitoring of power quality should take place with the help of automatic limit monitoring and automatically generated reports. This approach will give alarms/warnings if any parameter exceeds its limit. This reduces handling time for personnel as portable meters do not need to be installed but also when the system processes the collected information on its own. Since automatic detection of exceeded limit values may miss certain deviations, random sampling should be performed to verify the automatic monitoring.
94

Dynamic Behavior Of Water And Air Chemistry In Indoor Pool Facilities

Lester Ting Chung Lee (11495881) 22 November 2021 (has links)
<p>Swimming is the second most common form of recreational activity in the U.S. Swimming pool water and air quality should be maintained to allow swimmers, pool employees, and spectators to use the pool facility safely. One of the major concerns regarding the health of swimmers and other pool users is the formation of disinfection by-products (DBPs) in swimming pools. Previous research has shown that volatile DBPs can adversely affect the human respiratory system. DBPs are formed by reactions between chlorine and other compounds that are present in water, most of which are introduced by swimmers, including many that contain reduced nitrogen. Some of the DBPs formed in pools are volatile, and their transfer to the gas phase in pool facilities is promoted by mixing near the air/water interface, caused by swimming and pool features.</p> <p><a>Swimming pool water treatment processes can play significant roles in governing water and air quality.</a> Thus, it is reasonable to hypothesize that water and air quality in a swimming pool facility can be improved by renewing or enhancing one or more components of water treatment.</p> <p>The first phase of the study was designed to identify and quantify changes in water and air quality that are associated with changes in water treatment at a chlorinated indoor pool facility. Reductions of aqueous NCl<sub>3 </sub>concentration were observed following the use of secondary oxidizer with its activator. This inclusion also resulted in significant decreases in the concentrations of cyanogen chloride (CNCl) and dichloroacetonitrile (CNCHCl<sub>2</sub>) in pool water. The concentration of urea, a compound that is common in swimming pools and that functions as an important precursor to NCl<sub>3</sub> formation, as well as a marker compound for introduction of contaminants by swimmers, was also reduced after the addition of activator.</p> <p>The second phase of this study involved field measurements to characterize and quantify the dynamic behavior of indoor air quality (IAQ) in indoor swimming pool facilities, particularly as related to volatile compounds that are transferred from swimming pool water to air. Measurements of water and air quality were conducted before, during, and after periods of heavy use at several indoor pool facilities. The results of a series of measurements at different swimming pool facilities allowed for examination of the effects of swimmers on liquid-phase DBPs and gas-phase NCl<sub>3</sub>. Liquid-phase NCl<sub>3</sub> concentrations were observed to gradually increase during periods of high swimmer numbers (<i>e.g.</i>, swimming meets), while liquid-phase CHCl<sub>3</sub> concentration was nearly constant in the same period. Concentrations of urea displayed a steady increase each day during these periods of intensive use. In general, the highest urea concentrations were measured near the end of each swimming meet. </p> <p>Measurements of IAQ dynamics during phase 2 of the study demonstrated the effects of swimmers on the concentrations of gas-phase NCl<sub>3 </sub>and CO<sub>2</sub>, especially during swimming meets. The measured gas-phase NCl<sub>3</sub> concentration often exceeded the suggested upper limits of 300 µg/m<sup>3</sup> or 500 µg/m<sup>3 </sup>during swimming meets, especially during and immediately after warm-up periods, when the largest numbers of swimmers were in the pool. Peak gas-phase NCl<sub>3</sub> concentrations were observed when large numbers of swimmers were present in the pools; measured gas-phase concentrations were as high as 1400 µg/m<sup>3</sup>.<sup> </sup>Concentrations of gas-phase NCl<sub>3</sub> rarely reached above 300 µg/m<sup>3</sup> during regular hours of operation. Furthermore, the types of swimmers were shown to affect the transfer of volatile compounds, such as NCl<sub>3</sub>, from water to air<sub> </sub>in pool facilities. In general, adult competition swimmers promoted more rapid transfer of these compounds than youth competition swimmers or adult recreational swimmers. The measured gas-phase CO<sub>2</sub> concentration often exceeded 1000 ppm<sub>v</sub> during swimming meets, whereas the gas-phase CO<sub>2</sub> concentration during periods of non-use of the pool tended to be close to the background (ambient) CO<sub>2</sub> concentration or slightly more than 400 ppm<sub>v</sub>. This phenomenon was largely attributed to the activity of swimmers (mixing of water and respiratory activity) and the normal respiratory activity of spectators. </p> <p>IAQ models for gas-phase NCl<sub>3</sub> and CO<sub>2</sub> were developed to relate the characteristics of the indoor pool environment to measurements of IAQ dynamics. Several assumptions were made to develop these models. Specifically, pool water and indoor air were assumed to be well-mixed. The reactions that were responsible for the formation and decay of the target compounds were neglected. Two-film theory was used to simulate the net mass-transfer rate of volatile compounds from the liquid phase to the gas phase. Advective transport into and out of the air space of the pool were accounted for. The IAQ model was able to simulate the dynamic behavior of gas-phase NCl<sub>3</sub> during regular operating hours. Predictions of gas-phase NCl<sub>3</sub> dynamics were generally less accurate during periods of intensive pool use; however, the model did yield predictions of behavior that were qualitatively correct. Strengths of the model include that it accounts for the factors that are believed to have the greatest influence on IAQ dynamics and is simple to use. Model weaknesses include that the model did not account liquid-phase reactions that are responsible for formation and decay of the target compounds. The IAQ model for NCl<sub>3</sub> dynamics could still be a useful tool to form the basis for recommendations regarding the design and operation of indoor pool facilities so as to optimize IAQ.</p><p>Measurements of CO<sub>2</sub> dynamics indicated qualitatively similar dynamic behavior as NCl<sub>3</sub>. Because of this, it was hypothesized that CO<sub>2</sub> may represent a surrogate for NCl<sub>3</sub> for monitoring and control of IAQ dynamics. To examine this issue in more detail, a conceptually similar model of CO<sub>2 </sub>dynamics was developed and applied. The model was developed to allow for an assessment of the relative contributions of liquid®gas transfer and respiration by swimmers and spectators to CO<sub>2</sub> dynamics. The results of this modeling effort indicated that the similarity of CO<sub>2</sub> transfer behavior to NCl<sub>3</sub> may allow use of CO<sub>2</sub> as a surrogate during periods with few to no spectators in the pool; however, when large numbers of spectators are present, the behavior of CO<sub>2</sub> dynamics may not be representative of NCl<sub>3</sub> dynamics because of spectator respiration.</p><p></p> <br>
95

Avaliação dos índices de qualidade da água bruta de um manancial em área urbana /

Coneglian, Milena Guirado January 2020 (has links)
Orientador: Paulo Cesar Lodi / Resumo: A Política Nacional de Recursos Hídricos (Lei nº 9.433/1997) estabelece o enquadramento dos corpos hídricos como um dos instrumentos de gestão das águas. A CETESB – Companhia Ambiental do Estado de São Paulo, que compõe o Sistema Nacional de Gerenciamento de Recursos Hídricos criado por esta Lei, mantém Programa de Monitoramento da qualidade das águas e utiliza índices de qualidade das águas como ferramenta para a interpretação de dados ambientais complexos, com a finalidade de auxiliar no processo decisório das políticas públicas municipais além de informar técnicos e público em geral. Nesse sentido, com o objetivo de avaliar a evolução da qualidade de um manancial em área urbana e a sua conformidade em relação ao enquadramento, este estudo de caso apresenta uma análise sobre os Relatórios de Qualidade das Águas Interiores do Estado de São Paulo emitidos pela CETESB com ênfase nos arquivos relativos aos resultados dos parâmetros e indicadores de qualidade das águas do ponto de interesse, o Rio Lençóis, situado na UGRHi-13, de 2009 a 2018. O índice de conformidade ao enquadramento (ICE) foi aplicado anualmente e, também, bienalmente separados o período chuvoso do seco. Os principais resultados demonstram que as variáveis que mais apresentaram-se em desacordo com a Resolução CONAMA nº 357/2005 foram ‘ferro dissolvido’, ‘Escherichia coli’, ‘fósforo’ e ‘PFTHM’, proveniente de fontes difusas de poluição e em concentrações mais elevadas após ocorrência de chuvas, relacionadas ao a... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre
96

Infrarot-spektroskopische Untersuchungen zur nicht-invasiven Überwachung von Blutglucose und zur zuverlässigen und schnellen Qualitätskontrolle von Biopharmazeutika am Beispiel Insulin

Delbeck, Sven 09 February 2022 (has links)
Kumulative Dissertation, die sich mit den Herausforderungen der nichtinvasiven Blutglucosediagnostik sowie mit dem Qualitätsmonitoring von Biopharmazeutika am Beispiel Insulin beschäftigt. In beiden Forschungsbereichen wird die Infrarotspektroskopie eingesetzt, wobei verschiedene elektromagnetische Strahlungsbereiche (mitlleres und nahes Infrarot) zum Einsatz kommen. Ebenfalls werden unterschiedliche Messtechniken der Fourier-Transform-Infrarot-Spektroskopie eingesetzt, die die Vor- und Nachteile in den genannten Forschungsbereichen beleuchten.
97

Impact of power quality on PV performance of grid connected systems

Momoh, Ozaveshe January 2022 (has links)
The problem with the implementation of the PV generators is that majority of the UNDP offices are in developing and underdeveloped countries. Majority of these countries experience various problems with the power quality from the national electrical grid. There is also a second problem with the installed PV system, the problem is that the installed PV sources show a significant decrease in the expected annual yield ranging from 10 % – 60 % in some cases. The main aim of this thesis is to analyze the power quality in three countries (Nepal, Sao Tome and Namibia) and find the correlation between power quality and PV generation. This aim is done in five steps. The first step is the collection of measured data from the grid for a specific period of one year from July 2020 to August 2021. The collected data includes the current, voltage, power factor, frequency, reactive and active power. To achieve this, the Acuvim II power quality analyzer was sent to these three countries. In the second step, a literature review is done to research about power quality problems, identifying the power quality problems and analyzing the problems created by these identified power quality problems. In the three countries, undervoltage, overvoltage, swells, and sags where the main power quality problems which were recorded. The third step is a system case study process in which an in-depth analysis is done on the three PV systems and a simulation is done to understand the solar parameters which includes the specific yield, and performance ratio. The fourth step involves comparing the collected data from the PQ analyzer with the simulation results and determine the effects the power quality problems and system design have on the low annual yield. Also, the yearly amount of overvoltage and undervoltage in the three countries within the analysis period was analyzed. The voltage and fluctuation analysis also includes other power quality parameters which were measured. The collected parameters were analyzed and the correlation between the electrical grid requirements in the three countries were made with the recorded data. The final step involves recommending improvements and optimization techniques for the three systems to improve life cycle cost and long-term vision. Thus, analyzed results and simulated results are compared to evaluate the performance. The PV system in Namibia had the best grid conditions with all the grid parameters operating within the defined grid limits, there was a 30 % reduction in annual energy production in the Nepal system due to poor power quality conditions which included overvoltage, undervoltage, and frequency deviations. There was also a 50 % energy loss in the annual production of the PV systeminstalled in Sao Tome. Sao Tome also had the highest number of recorded outages with an average of 6 – 7 hours of outages recorded daily. Power quality problems recorded in Sao Tome included voltage fluctuation problems and frequency deviations.
98

Web Based Cloud Interaction and Visualization of Air Pollution Data

Nergis Damirag, Melodi January 2019 (has links)
According to World Health Organization, around 7 million people die every year due to diseases caused by air pollution. With the improvements in Internet of Things in the recent years, environmental sensing systems has started to gain importance. By using technologies like Cloud Computing, RFID, Wireless Sensor Networks, and open Application Programming Interfaces, it has become easier to collect data for visualization on different platforms. However, collected data need to be represented in an efficient way for better understanding and analysis, which requires design of data visualization tools. The GreenIoT initiative aims to provide open data with its infrastructure for sustainable city development in Uppsala. An environmental web application is presented within this thesis project, which visualizes the gathered environmental data to help municipality organizations to implement new policies for sustainable urban planning, and citizens to gain more knowledge to take sustainable decisions in their daily life. The application has been developed making use of the 4Dialog API, which is developed to provide data from a dedicated cloud storage for visualization purposes. According to the evaluation presented in this thesis, further development is needed to improve the performance to provide faster and more reliable service as well as the accessibility to promote openness and social inclusion. / Enligt World Health Organization dör 7 miljoner människor varje år på grund av sjukdomar orsakade av luftföroreningar. Med förbättringar inom Internet of Things under senare år, har betydelsen av system för miljösensorer. Genom att använda tekniker som molntjänster, RFID, trådlösa sensornätverk och öppna programmeringsgränssnitt, har det blivit enklare att samla in data för visualisering på olika plattformar. Men insamlad data behöver bli representerad på ett effektivt sätt för bättre förståelse och analys, vilket kräver utformande av verktyg för visualisering av data. Initiativet GreenIoT strävar mot att erbjuda öppen data med sin infrastruktur för hållbar stadsutveckling i Uppsala. I detta arbete presenteras en webb-tillämpning, som visualiserar den insamlade miljödatan för att hjälpa kommunen att implementera nya policies för hållbar stadsutveckling, och stimulera medborgare till att skaffa mer kunskap för att göra miljövänliga val i sin vardag. Tillämpningen har utvecklats med hjälp av 4Dialog API, som tillhandahåller data från lagring i molnet för visualiseringssyfte. Enligt den utvärdering som presenteras i denna rapport konstateras att vidare utveckling behövs för att förbättra dels prestanda för att erbjuda en snabbare och mer tillförlitlig service, och dels åtkomstmöjligheter för att främja öppenhet och social inkludering.
99

Concentration profiles and mapping of ambient air quality in the Shenandoah National Park

Godrej, Adil N. January 1982 (has links)
A graphical system was developed to represent airborne air quality monitoring data. The representations developed included three—dimensional spatial mapping, percentage and frequency distributions, and altitude—based scatter diagrams. Elementary statistical analyses and correlations of the measured parameters were also performed. Data gathered in eight flights to the Shenandoah National Park during the summer months of 1981 were analyzed. Sulfur dioxide levels were found to be in the 5 - 15 ppb range, nitrogen oxides were in the 4 — 10 ppb range, nitrous oxide was in the 2 - 5 ppb range, nitrogen dioxide was in the 2 - 5 ppb range, ozone was in the 35 - 70 ppb range and visual range was in the 5 — 90 mile range. The data representation system proved to be an easier and more useful method of displaying the data than the previously existing system. / Master of Science
100

Power quality analysis using relay recorded data

Birdi, Harjit Singh 01 September 2006
Demand for electrical power is increasing everyday. Along with the increase in power demand, the characteristics of the loads are also changing. From being high power consuming, simple, robust loads, today loads are more efficient, but at the same time more sensitive. The performance and life of these highly sensitive loads depend a lot on the quality of power supplied to them. <p>Power quality is any deviation of the voltage or current waveform from its normal sinusoidal waveshape. These disturbances include, but are not limited to, sag, undervoltage, interruption, swell, overvoltage, transients, harmonics, voltage flicker and any other distortions to the sinusoidal waveform. Occurrence of one or more of such disturbances is called a power quality event. Automatic classification of these disturbances is important for quick determination of the causes and to characterize possible impacts of the disturbances.<p>Modern microprocessor based protective relays have numerous integrated functions that allow them to provide information on power quality events. It is proposed to utilize the existing numerical relays to analyze the quality of power at any point in the power system. The numerical relays can be programmed to capture the oscillographic waveform or any disturbance on the analogue signal or change of state of the digital signals and store it in the form of Common Format For Transient Data Exchange (COMTRADE) format. These records are then transferred to a central monitoring workstation for off-line analysis. <p>This thesis describes a technique to automate the classification and analysis of the power quality events using relay recorded data. The technique uses voltage duration and magnitude (as specified in the IEEE Std. 1159 - 1995, IEEE Recommended Practice for Monitoring Electric Power Quality) of three phases to detect and classify the events. The classified results are then presented in a user-friendly graphical form. Fast Fourier Transform (FFT) is used to estimate the fundamental frequency and harmonic components in power systems. The graphical user interface of the power quality analysis tool is developed using Microsoft Visual C++ IDE and the algorithms are programmed in C++. <p>The proposed technique was tested using data obtained by simulating different power system disturbances as well as on the data recorded by relays. The algorithms were able to classify the power quality events accurately. In the future, this facility will: enhance the real time monitoring of power quality and provide statistical analysis of available power quality data. From the utility viewpoint, it would allow them to monitor power quality in a cost effective manner and assist in preventive and predictive maintenance besides helping them to fix differential tariff based on the quality of the delivered power. It may also turn out to be a smart tool for them to penalize the consumer polluting the power quality.

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