This thesis presents an artificial neural network (ANN) approach to diagnose and detect faults in oil-filled power transformers based on dissolved gas-in-oil analysis. The goal of the research is to investigate the available transformer incipient fault diagnosis methods and then develop an ANN approach for this purpose. This ANN classifier should not only be able to detect the fault type, but also should be able to judge the cellulosic material breakdown. This classifier should also be able to accommodate more than one type of fault. This thesis describes a two-step ANN method that is used to detect faults with or without cellulose involved. Utilizing a feedforward artificial neural network, the classifier was trained with back-propagation, using training samples collected from different failed transformers. It is shown in the thesis that such a neural-net based approach can yield a high diagnosis accuracy. Several possible design alternatives and comparisons are also addressed in the thesis. The final system has been successfully tested, exhibiting a classification accuracy of 95% for major fault type and 90% for cellulose breakdown. / Master of Science

An arterialblood gas analysis which is conducted in critical care areas contributes to the assessment of a patient's ventilatory status and acid -base balance. The purpose of this research was to determine the relationship of time delays and temperature on the result of a blood gas analysis. The objective was to either accept or refute the null hypothesis, that there is no relationship between temperature and time delays and an arterial blood gas result Fifteen subjects were randomly selected. The researcher drew three samples of arterial blood from each subject. Ethical principles were observed. An inferential non-parametric statistic was used. The chi-squared test was used to test the hypothesis and the Friedman and the Wilcoxon signed ranks test were used to test the differences between the means. The results revealed that there was a relationship between time delays, temperature and the arterial blood gas result. The null hypothesis was rejected. / Health Stusies / M.A. (Health Studies)

Einleitung: Alpakas gehören zu einer Tiergruppe, die in den vergangenen Jahren im Patientengut der Tierärzte immer häufiger anzutreffen ist. Daher ist es von großer Bedeutung, sich mit der Physiologie und Pathologie dieser Tierart zu beschäftigen. Die Versorgung der Neonaten spielt dabei eine große Rolle. Da Alpakacrias, wenn überhaupt, dann erst sehr spät, klinische Anzeichen einer Erkrankung zeigen, ist es für den Untersucher von großem Nutzen, einen Einblick in den Blutgas- und Säure-Basen-Haushalt, sowie Kenntnis von den hämatologischen und blutchemischen Parametern des Neonaten zu erhalten. Des Weiteren bietet die Blutuntersuchung ein wichtiges Hilfsmittel zur Überprüfung der Versorgung mit kolostralen Antikörpern. Ziele der Untersuchungen: Ein Ziel der Untersuchungen war die Erstellung von bisher nicht vorhandenen Referenzwerten für die venöse Blutgasanalyse, die Hämatologie und für einige blutchemische Parameter bei gesunden, lebensfrischen Alpakacrias innerhalb der ersten drei Lebenstage. Des Weiteren sollte in diesem Zusammenhang die Eignung eines mobil einsetzbaren Blutgasanalysegerätes (epoc®, Fa. Alere GmbH, Köln) für die Tierart Alpaka eruiert werden. Hierfür wurden Doppelbestimmungen der Proben mit einem etablierten stationären Blutgasanalysegerät (ABL90 FLEX®, Fa. Radiometer, Kopenhagen) durchgeführt. Tiere, Material und Methoden: In die Studie wurden 20 gesunde neugeborene Alpakacrias integriert. Die Fohlen stammten vornehmlich aus Stuten, die zur Geburtsüberwachung in die Klinik eingestallt wurden, bei anderen handelte es sich um solche, die innerhalb der ersten Lebensstunden wegen vermeintlich verzögerter Tränkeaufnahme vorgestellt worden waren, was sich aber nicht bestätigte. Alle Alpakafohlen wurden nach dem Gießener Vorsorgeschema II für neonatale Equiden klinisch untersucht. Anschließend erfolgte 3-8 Stunden p. n., 24 Stunden p. n. und 72 Stunden p. n. je eine Blutprobenentnahme. Der erste Analysezeitpunkt wurde bewusst nicht unmittelbar post natum gewählt, da die Etablierung einer stabilen Prägungsphase zwischen Muttertier und Cria nach der ersten Tränkeaufnahme abgewartet werden sollte. Die Blutentnahme erfolgte nach Reinigung und Desinfektion aus der ungestauten V. jugularis externa im Bereich des sechsten Halswirbels. Die Blutgasanalyse wurde innerhalb von 15 Minuten mit den zuvor genannten Blutgasautomaten durchgeführt. Die hämatologischen Parameter wurden mit dem pocH-100 iV (Fa. Sysmex Deutschland GmbH, Norderstedt) bestimmt, die blutchemischen Untersuchungen erfolgten mit dem FUJI DRI CHEM 3500 (Fa. Sysmex Deutschland GmbH, Norderstedt). Insgesamt wurden 55 Blutproben entnommen und analysiert. Pro Analysegerät (epoc®, ABL90 FLEX®, pocH-100 iV, FUJI DRI-CHEM 3500) wurden je 55 Messungen durchgeführt. Die statistische Auswertung erfolgte mit dem Programm IBM SPSS Statistics 22.0. Die Normalverteilung wurde mittels Shapiro-Wilk-Test überprüft. Für den Gerätevergleich (epoc®/ABL90 FLEX®) fand der Wilcoxon-Test Anwendung. Der Vergleich der Zeitpunkte erfolgte über den Friedman-Test für verbundene Stichproben. Des Weiteren wurden für die einzelnen Parameter der Median und die Perzentile, bzw. der Mittelwert und die Standardabweichung bestimmt. Die grafische Darstellung erfolgte mit Boxplots und Bland-Altman-Plots. Ergebnisse: Im Gerätevergleich konnte insgesamt auf eine gute Übereinstimmung der Messwerte geschlossen werden. Signifikante und gleichzeitig klinisch relevante Unterschiede gab es lediglich bei der Bestimmung der Sauerstoffsättigung und des Hämatokrits, was auf unterschiedliche Mess- und Berechnungsmethoden bei den Geräten zurückzuführen ist. So liegen die Hämatokritwerte beim epoc® deutlich unter denen vom ABL90 FLEX®. In diesem Zusammenhang wichtig für die Interpretation der Ergebnisse ist, dass für jedes Messgerät die individuellen Referenzbereiche berücksichtigt werden müssen. Die venöse Blutgasanalyse ergab für gesunde Crias zu Beginn des ersten Lebenstages einen pH-Wert von 7,34 – 7,40, einen Sauerstoffpartialdruck (pO2) von 21,6 – 29,2 mmHg, einen Kohlendioxidpartialdruck (pCO2) von 37,3 – 46,0 mmHg, eine Sauerstoffsättigung (sO2) von 30,5 – 48,0 %, ein aktuelles Bikarbonat (HCO3-) von 21,3 – 25,1 mmol/l, eine Standardbasenabweichung (SBE) von -3,3 – 0,2 mmol/l und einen Laktatgehalt von 1,6 – 3,4 mmol/l. Der pH Wert ähnelte im Verlauf dabei dem von Kälbern und Lämmern gleichen Alters, der pO2 war insgesamt etwas niedrig, aber konstant und ähnelte über den Messzeitraum dem von Kälbern. Es wurden bei den Crias im Vergleich zu Fohlen, Kälbern und Lämmern niedrigere pCO2-Werte festgestellt. Die Sauerstoffsättigung ähnelte der von Equidenfohlen, über den Messzeitraum fällt die Konzentration im Mittel geringfügig ab, bei den anderen Vergleichstierarten steigt sie an. Die Glukosekonzentrationen waren postnatal höher als bei anderen Haustierneonaten (3-8 h p.n.: 4,4 – 8,2; 24 h p.n.: 7,3 – 12,8; 72 h p.n.: 7,3 – 16,2 mmol/l). Laktat kann nicht, wie es beim Equidenfohlen postuliert wird, als Indikator für den Gesundheitszustand eines Alpaka-Crias genutzt werden. Hämatologisch sind die spezielle Form und die hohe Anzahl der Alpakaerythrozyten, die hohe Zahl an Leukozyten und Thrombozyten (speziell bei den Crias), sowie die hohe MCHC zu nennen. Schlussfolgerungen: Es konnten teilweise bisher fehlende Daten zur venösen Blutgasanalyse für die Beurteilung der Stoffwechsellage neugeborener Alpakacrias etabliert werden. Das mobile Blutgasgerät epoc® stellt eine für die Anwendung geeignete Alternative dar.

This dissertation thesis is focused on the evaluation of the dissolved gas analysis in the power oil transformer diagnosis. This thesis derives from known, in standards, directives and literature shows realities which are fill in new pieces of knowledge as determining of gases important for evaluation of the transformer condition, specifying of current methods accuracy and investigating of accuracy change for interpretation of dissolved gases. The part of this thesis is the application of mathematic methods for detailed description of individual transformer failures and determining of dominant gas which are generating in power oil transformer. Obtain conclusion will be contribution for transformer diagnostics and will be applicable in industrial practice.

Existem inúmeras ferramentas e metodologias para o diagnóstico de falhas em transformadores de potência, tanto para a monitoração e acompanhamento do equipamento em operação (planta fixa) como àquele retirado e abrigado em laboratórios de unidades fabris. Em função dos custos envolvidos no transporte dos equipamentos, manuseio para a substituição, energia não faturada nos períodos de manobras e custos adicionais dos ensaios para voltar com o equipamento em operação, as principais metodologias que se destacam são aquelas direcionadas ao equipamento em operação e também as escolhidas para serem analisadas neste trabalho. Após um estudo sistemático dessas metodologias, tais como termográfica, emissão acústica e análise dos gases dissolvidos no óleo, denominada cromatografia, verificou-se que esta última se destaca como a mais econômica e a mais difundida na identificação das falhas. Contudo, na cromatografia, existem diferentes critérios de análise baseados nas relações e quantidades de diferentes tipos de gases e que são usados pelas companhias concessionárias de forma indiscriminada, gerando muitas dúvidas quanto à sua validade. Esta pesquisa teve como principal foco a comparação desses critérios usando como base de dados àqueles fornecidos pela IEC e pela Companhia Paulista de Força e Luz (CPFL). A base de dados da CPFL contem aproximadamente quatro mil ensaios cromatográficos, colhidas nas ultimas três décadas correspondendo a 500 unidades transformadoras, nas potências de 5,0 a 50 MVA, instaladas em subestações nas tensões primárias de 69 e 138 kV, e secundária de 13,8 kV. Também fez parte dessa pesquisa a definição de um conjunto de critérios que melhor identificam as falhas em transformadores. / There are numerous tools and methodologies for fault diagnosis in power transformers, either for monitoring and tracking equipment in operation (fixed plant) or for those removed and housed in laboratories plants. Due to the costs involved in transporting the equipment, handling for the replacement, unbilled energy during periods of maneuvers and additional costs of the tests to return with the equipment in operation, the main methodologies that stand out are those using the equipment in operation and also those chosen to be analyzed in this work. After a systematic study of these methods such as thermography, and acoustic emission and analysis of gases dissolved in the oil, known as chromatography, it was found that the latter stands out as the most economical and most widely in the identification of faults. However, in chromatography, there are different criteria based on the relationships of different types and quantities of gases that are used by electrical companies indiscriminately, raising many questions about its validity. This research was mainly focused on the comparison of these criteria using the database as those provided by IEC and the Companhia Paulista de Força e Luz (CPFL). The database of CPFL contains approximately four thousand chromatographic assays from the last three decades, corresponding 500 transforming units, from 5 to 50 MVA, in substations with primary voltages of 138 kV and 69 and secondary of 13,8 kV. Was also studied the definition of a set of criteria which identify faults in transformers.

Existem inúmeras ferramentas e metodologias para o diagnóstico de falhas em transformadores de potência, tanto para a monitoração e acompanhamento do equipamento em operação (planta fixa) como àquele retirado e abrigado em laboratórios de unidades fabris. Em função dos custos envolvidos no transporte dos equipamentos, manuseio para a substituição, energia não faturada nos períodos de manobras e custos adicionais dos ensaios para voltar com o equipamento em operação, as principais metodologias que se destacam são aquelas direcionadas ao equipamento em operação e também as escolhidas para serem analisadas neste trabalho. Após um estudo sistemático dessas metodologias, tais como termográfica, emissão acústica e análise dos gases dissolvidos no óleo, denominada cromatografia, verificou-se que esta última se destaca como a mais econômica e a mais difundida na identificação das falhas. Contudo, na cromatografia, existem diferentes critérios de análise baseados nas relações e quantidades de diferentes tipos de gases e que são usados pelas companhias concessionárias de forma indiscriminada, gerando muitas dúvidas quanto à sua validade. Esta pesquisa teve como principal foco a comparação desses critérios usando como base de dados àqueles fornecidos pela IEC e pela Companhia Paulista de Força e Luz (CPFL). A base de dados da CPFL contem aproximadamente quatro mil ensaios cromatográficos, colhidas nas ultimas três décadas correspondendo a 500 unidades transformadoras, nas potências de 5,0 a 50 MVA, instaladas em subestações nas tensões primárias de 69 e 138 kV, e secundária de 13,8 kV. Também fez parte dessa pesquisa a definição de um conjunto de critérios que melhor identificam as falhas em transformadores. / There are numerous tools and methodologies for fault diagnosis in power transformers, either for monitoring and tracking equipment in operation (fixed plant) or for those removed and housed in laboratories plants. Due to the costs involved in transporting the equipment, handling for the replacement, unbilled energy during periods of maneuvers and additional costs of the tests to return with the equipment in operation, the main methodologies that stand out are those using the equipment in operation and also those chosen to be analyzed in this work. After a systematic study of these methods such as thermography, and acoustic emission and analysis of gases dissolved in the oil, known as chromatography, it was found that the latter stands out as the most economical and most widely in the identification of faults. However, in chromatography, there are different criteria based on the relationships of different types and quantities of gases that are used by electrical companies indiscriminately, raising many questions about its validity. This research was mainly focused on the comparison of these criteria using the database as those provided by IEC and the Companhia Paulista de Força e Luz (CPFL). The database of CPFL contains approximately four thousand chromatographic assays from the last three decades, corresponding 500 transforming units, from 5 to 50 MVA, in substations with primary voltages of 138 kV and 69 and secondary of 13,8 kV. Was also studied the definition of a set of criteria which identify faults in transformers.

No description available.

An arterialblood gas analysis which is conducted in critical care areas contributes to the assessment of a patient's ventilatory status and acid -base balance. The purpose of this research was to determine the relationship of time delays and temperature on the result of a blood gas analysis. The objective was to either accept or refute the null hypothesis, that there is no relationship between temperature and time delays and an arterial blood gas result Fifteen subjects were randomly selected. The researcher drew three samples of arterial blood from each subject. Ethical principles were observed. An inferential non-parametric statistic was used. The chi-squared test was used to test the hypothesis and the Friedman and the Wilcoxon signed ranks test were used to test the differences between the means. The results revealed that there was a relationship between time delays, temperature and the arterial blood gas result. The null hypothesis was rejected. / Health Stusies / M.A. (Health Studies)

Le travail de cette thèse avait pour objectif de contribuer à apporter de solutions au problème de surveillance des transformateurs par le biais des analyses de l'huile. La méthodologie et les résultats présentés s'appuient sur des cas concrets de transformateurs expertisés et des analyses d'huile réalisées en laboratoire. Les règles de diagnostic pour les grandeurs physico-chimiques ont été établies pour chaque équipement électrique et pour chaque type de fluide. Ces règles ont montré l'importance des paramètres liés à l'échantillonnage, à la méthode d'analyse et à la conception du transformateur et notamment l'importance du régleur en charge. Un lien entre analyse, défaut et origine du défaut a été établi et constitue la base de l'outil de diagnostic proposé. Ainsi l'outil identifie, à l'aide des analyses physico-chimiques réalisées sur le fluide, des défauts possibles et propose des origines de panne du transformateur. Finalement, une piste de pronostic d'état est abordée afin de développer le diagnostic. / The scope of this thesis was designed to contribute to solving the transformer monitoring problem of monitoring of transformers by analyses oil. The methodology and the results presented are based on concrete cases of assessed de-tanked transformers and oil analysis laboratory. The rules of diagnosis for physicochemical quantities have been established for each electrical equipment and for each type of fluid. These rules showed the importance of the sampling parameters, the method of analysis and the design of the transformer and especially the significance of the on load tap changer. A link between analysis, defect and origin of the defect was established which is the basis of the proposed diagnosis tool. Thanks to the chemical analyses, this tool enables to identify potential defects in the transformer and reveals some origins of failures.

Made available in DSpace on 2016-08-15T20:31:08Z (GMT). No. of bitstreams: 1 RejaneSS_DISSERT.pdf: 2305528 bytes, checksum: 47bde97e4a35896152b153a7383736d8 (MD5) Previous issue date: 2012-07-04 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / This study evaluated the clinical, hematological, biochemical and blood gas responses and the oxidative stress in sheep submitted to hiperacute anemia and subsequently underwent to homologous transfusion with whole blood, either fresh, or stored for 15 or 35 days. Eighteen adult Santa Inez crossbred sheep, males and females, were used, weighing on average 52kg. The animals were submitted to a single phlebotomy to remove 40% of blood volume and equally divided into three experimental groups: G0 - animals receiving fresh blood; G15 receiving blood stored for 15 days; and G35 - receiving blood stored for 35 days. The animals were submitted to clinical examination and blood collection 24 h after induction of anemia (T0), 30 minutes after transfusion (T30), six, twelve, twenty-four, forty-eight, seventy-two and ninety-six hours post-transfusion (T6, T12, T24, T48, T72 and T96, respectively), and eight and sixteen days post-transfusion (T8d and T16d, respectively). The blood bags stored for 35 days showed an increase in K, pCO2, pO2, lactate, plasma hemoglobin and decreased plasma pH, sodium and leukocytes. The sheep transfused from all groups had increased GV, red cell count and total hemoglobin in the T30. The animals of the G35 had higher plasma hemoglobin in T12, a significant decrease in blood pH indicating a mild metabolic acidosis on T96. With respect to oxidative stress, was observed a decreased on catalase values of the G35 at T30, T6, T12 and T24, suggesting the occurrence of hemolysis witch was supported by the concomitant increase in the total bilirubin values at the same periods. Animals that received blood stored for 35 days showed higher alteration on hematological, blood gas, biochemical and oxidative stress parameters / O presente trabalho objetivou avaliar as respostas clínicas, hematológicas, bioquímicas, hemogasométricas e o estresse oxidativo de ovinos induzidos à anemia superaguda e transfundidos com sangue total fresco ou armazenado por dois diferentes períodos (15 e 35 dias). Foram utilizados 18 ovinos, machos e fêmeas, com idade entre 3 e 4 anos, pesando em media 52kg. Os animais foram submetidos a uma única flebotomia para retirada de 40% do volume sanguíneo e divididos em três grupos experimentais, sendo o G0 composto por animais que receberam sangue fresco, G15 e G35 animais que receberam sangue armazenado em bolsas CPDA-1 por 15 e 35 dias, respectivamente. Foi realizado exame clínico e coleta de amostras de sangue 24 horas pós-indução da anemia (T0), 30 minutos pós-transfusão (T30), seis, 12, 24, 48, 72 e 96 horas após à transfusão (T6, T12, T24, T48, T72, T96, respectivamente) e oito e dezesseis dias após à transfusão (T8d e T16d, respectivamente). O sangue armazenado por 35 dias apresentou aumento do potássio, pCO2, pO2, lactato, hemoglobina plasmática e diminuição do pH, sódio e leucócitos. Ovinos transfundidos no T30 apresentaram aumento significativo do VG, hemácias e hemoglobina total. Os animais do G35 apresentaram maiores valores de hemoglobina plasmática no T12 e diminuição do pH sanguíneo, caracterizando leve acidemia metabólica no T96. Com relação ao estresse oxidativo o G35 apresentou redução da catalase no T30, T6, T12 e T24, indicando a ocorrência de hemólise, o que foi corroborado pelo aumento concomitante da bilirrubina. Os animais que receberam sangue armazenado por 35 dias apresentaram maiores alterações hematológicas, hemogasométricas, bioquímicas e oxidativas