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IMTS and WOT form a PC-based hardware and software system designed to continuously monitor large numbers of rotating machinery, evaluate each machine's condition through a series of user-definable standards, and alert operators to potential problems. This system requires a rack of data acquisition equipment located near the machines being monitored and a PC that can be located remotely. This system has been tested under actual plant conditions at the Virginia Tech Power Plant. The software operates under Windows 3.1, and allows data to be acquired and evaluated simultaneously. This thesis discusses the development of this system over earlier versions and the installation procedures and first runs at the Power Plant. It discusses in detail the operation of some of the main programs that comprise the Intelligent Trending and Expert System. / Master of Science

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-06-03T23:48:41Z No. of bitstreams: 1 EdsonJacksonDeMedeirosNeto_DISSERT.pdf: 2349422 bytes, checksum: 58dbff032ce7a77c69ab57cce418be2d (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-06-07T19:55:39Z (GMT) No. of bitstreams: 1 EdsonJacksonDeMedeirosNeto_DISSERT.pdf: 2349422 bytes, checksum: 58dbff032ce7a77c69ab57cce418be2d (MD5) / Made available in DSpace on 2016-06-07T19:55:39Z (GMT). No. of bitstreams: 1 EdsonJacksonDeMedeirosNeto_DISSERT.pdf: 2349422 bytes, checksum: 58dbff032ce7a77c69ab57cce418be2d (MD5) Previous issue date: 2015-11-09 / O grande volume de dados gerados como resultado da supervis?o de processos de automa??o na ind?stria gerou como consequ?ncia um vasto espa?o de armazenamento em disco, assim como dificuldade na transmiss?o destes dados por links de telecomunica??es. Os algoritmos de compress?o com perda de dados surgiram na d?cada de 90 com intuito de solucionar estes problemas, passando a serem utilizados em sistemas de supervis?o industrial para a compress?o de dados em tempo real. Para isso estes foram projetados para eliminar informa??es redundantes e indesejadas de forma simples e eficiente. No entanto, os par?metros destes algoritmos necessitam de serem configurados para cada vari?vel de processo, tornando invi?vel a configura??o manual em caso de sistemas que supervisionam milhares de vari?veis. Nesse contexto este trabalho prop?e o algoritmo Adaptive Swinging Door Trending, que consiste numa adapta??o do Swinging Door Trending, em que seus principais par?metros s?o ajustados dinamicamente atrav?s da an?lise de tend?ncias do sinal. Prop?e-se tamb?m uma an?lise comparativa de desempenho dos algoritmos de compress?o com perda de dados aplicados sobre vari?veis de processo de s?ries temporais e cartas dinamom?tricas de fundo de po?o. Os algoritmos abordados para efeito comparativos foram os lineares por partes e os de transformadas. / The great amount of data generated as the result of the automation and process supervision in industry implies in two problems: a big demand of storage in discs and the difficulty in streaming this data through a telecommunications link. The lossy data compression algorithms were born in the 90?s with the goal of solving these problems and, by consequence, industries started to use those algorithms in industrial supervision systems to compress data in real time. These algorithms were projected to eliminate redundant and undesired information in a efficient and simple way. However, those algorithms parameters must be set for each process variable, becoming impracticable to configure this parameters for each variable in case of systems that monitor thousands of them. In that context, this paper propose the algorithm Adaptive Swinging Door Trending that consists in a adaptation of the Swinging Door Trending, as this main parameters are adjusted dynamically by the analysis of the signal tendencies in real time. It?s also proposed a comparative analysis of performance in lossy data compression algorithms applied on time series process variables and dynamometer cards. The algorithms used to compare were the piecewise linear and the transforms.

Prior to the year 2007, Eskom Distribution followed a method of load forecasting (now referred to as legacy method in this report) that was based on collecting customer applications, historical load trending, and relied on the planner’s knowledge of the area to a large extent. It was based in a conventional Microsoft Excel spreadsheet. On seeking to improve its load forecasting approach, the utility adopted a technique that was based on spatial forecasting. This new technique was called a geographical based load forecasting (GLF) technique which was performed by using a custom based tool, called PowerGLF. The aim of this research was to assess any improvements (or lack thereof) that were brought about by adopting the GLF method as compared to the legacy method that was used previously. The hypothesis to be tested was declared as: “The use of the GLF method that was introduced to Eskom Distribution Planning brings about the improvement on the planning process of infrastructure that is adequate, reliable and economic, when compared to the legacy method that was used before it.” To carry out this assessment, a case study method was followed. Real network studies that were compiled in 2006 and 2007 were used. These network studies were based on GLF method and the legacy method. The load forecasts from the case studies were evaluated on forecast accuracy, how they influenced the planning of adequate, reliable and economic (ARE) network infrastructure and their impact on the procurement and construction of the network infrastructure (which represent the actual utility expenditure on infrastructure). The statistical comparative analysis was done. The research results revealed that the legacy method was more accurate than the GLF method in both the case studies that were evaluated. However, regarding the ability of a load forecast method to support the planning process, the GLF method showed to be supporting the planning of adequate, reliable and economic infrastructure better than the legacy method. It was found that the forecast error for the GLF and legacy method do not affect the utility infrastructure procurement and construction. Based on the test results, the study reached a conclusion that the use of the GLF method that was introduced to Eskom Distribution Planning brings about the improvement in the planning process of infrastructure that is adequate, economic and reliable when compared to the legacy method that was used before it. The author wishes to express that the results of this study must not be taken as a generic conclusive finding regarding the evaluated load forecasting methods; they are applicable to the tested case studies. To get to a general conclusive result, more case studies would need to be carried out where clear and consistent evidence on performance of these load forecasting methods will be seen. The findings of this study can be used as part of a larger sample if such a larger population of case studies was to be evaluated. The methodology followed in this research can be repeated and followed when similar assessments are done in future.

The mineral resources of the Tintic Mining District are influenced by three major events in its geologic history; the Mesozoic Sevier Orogeny, Paleogene volcanism and Late Neogene Basin and Range extension. In this paper a detailed analysis of each these geologic events is presented to help us understand the structural host, mineralization and exhumation of the Tintic Mining District ore. A kinematic analysis of the faults was completed to determine the origin of NE-trending faults, Sevier Orogeny or Basin and Range extension, in the northern part of the East Tintic Mountains in Allens Ranch 7.5' quadrangle, near the eastern margin of the Great Basin of central Utah. The structural history of the NE-trending faults found in the quadrangle was reconstructed to determine stress directions and fault kinematics. Maximum paleostress direction for the East Tintic fold and thrust system is between 80º–100º with fold axes oriented at ~350º. For example, the Gardison Ridge and Tintic Prince faults are NE-trending right-lateral transverse faults that formed at ~30º to paleostress directions similar to those of the Sevier Orogeny. The dominant NE-trending faults in the region are likely due to (1) differential shortening during progressive orocline development, (2) the pre-deformational Pennsylvanian-Permian Oquirrh basin geometry, and (3) the influence of the Leamington transverse zones of the Provo salient. Conversely, mixed paleostress directions for the north-trending Tintic Davis Canyon fault show it is a Basin and Range extension-related normal fault that may have originated as a Sevier related fault. Other N-trending faults within the quadrangle are only related to Basin and Range extension. However, large offset, range-bounding faults are buried by valley fill throughout the quadrangle and no young fault scarps are identified cutting Lake Bonneville deposits. An Oligocene to Miocene suite of extrusive volcanic units in the quadrangle correlates well with those of the East Tintic and Soldiers Pass volcanic fields. The Paleogene volcanic section is dominated by a suite of high-K calc-alkaline extrusive rocks (35 to 32 Ma). This intermediate to silicic sequence was followed by eruption of the mildly alkaline Mosida Basalt during the Miocene (19.5 Ma) marking the transition from subduction-related intermediate and silicic volcanism to extension-related mafic volcanism in the eastern Great Basin.

This study visualizes and quantifies extant publications of rural landscape research (RLR) inWeb of Science using CiteSpace for a wide range of research topics, from a multi-angle analysis of the overall research profile, while providing a method and approach for quantitative analysis of massive literature data. First, it presents the number of papers published, subject distribution, author network, the fundamental condition of countries, and research organizations involved in RLR through network analysis. Second, it identifies the high-frequency and high betweenness-centrality values of the basic research content of RLR through keyword co-occurrence analysis and keyword time zones. Finally, it identifies research fronts and trending topics of RLR in the decade from 2009 to 2018 by using co-citation clustering, and noun-term burst detection. The results show that basic research content involves protection, management, biodiversity, and land use. Five clearer research frontier pathways and top 20 research trending topics are extracted to show diversified research branch development. All this provides the reader with a general preliminary grasp of RLR, showing that cooperation and analysis involving multiple disciplines, specialties, and angles will become a dominant trend in the field.

This doctoral thesis focuses on the problems of IGBT failure prediction in pulse converters using measurable changes of selected parameters (so--called trending variables) being influenced of transistor degradation during aging. Firstly the state--of--the--art in this field is presented in the dizertation. The description of designed and constructed automated measurement stand follows, enabling monitoring and recording of switching processes during accelerated aging. Further the problems of high--bandwidth measurement of electrical quantities during IGBT switching are described. Especially the problems of current sensing are analyzed and the most suitable sensor is selected. The data recorded using the developed apparatus served to identify potential trending variables allowing the failure prediction. Here the dependence of trending variables on aging and on parasitic influences (current, temperature, voltage) had to be distinguished. Finally the evaluation of trending variables is performed. Their insignificant sensitivity on accelerated aging is shown which complicates their practical implementation for the purpose of failure prediction.

Le premier chapitre examine les caractéristiques statistiques à long terme des rendements financiers en France et aux USA. Les propriétés des différents actifs font apparaître qu’à long terme les actions procurent un risque sensiblement moins élevé. En outre, les propriétés de retour à la moyenne des actions justifient qu’elles soient utilisées dans une stratégie de cycle de vie comme « option par défaut » de plans d’épargne retraite. Le chapitre deux fournit une explication au débat sur l'hypothèse d’efficience des marchés. La cause du débat est souvent attribuée à la petite taille des échantillons et à la faible puissance des tests statistiques dédiés. Afin de contourner ce problème, nous utilisons l'approche développée par Campbell et Viceira (2005) qui utilisent une méthode VAR pour mettre en évidence l’existence de retour vers la moyenne dans le cours des actifs risqués.Le troisième chapitre évalue la vitesse de convergence des cours des actions. Un moyen classique pour caractériser la vitesse de retour vers la moyenne est la « demi-vie ». En comparant les indices boursiers de quatre pays développés (États-Unis, Royaume-Uni, France et Japon) sur la période 1950-2014, nous établissons une vitesse de convergence significative, avec une demi-vie entre 4,0 et 5,8 ans.Le dernier chapitre présente les résultats d'un modèle conçu pour étudier les interactions entre la démographie et les régimes de retraite. Afin d’étudier les risques inhérents à l’utilisation des revenus du capital pour financer les retraites, nous utilisons un « Trending OU process » au lieu d’un MBG classique pour modéliser les rendements. Pour un épargnant averse au risque le marché pourrait concurrencer les régimes par répartition. / Chapter one examines the long run statistical characteristics of financial returns in France and the USA for selected assets. This study clearly shows that the returns’ distributions diverge from the Gaussian strategy as regards longholding periods. Thereafter we analyze the consequences of the non-Gaussian nature of stock returns on default-option retirement plans.Chapter two provides a reasonable explanation to the strong debate on the Efficient Market Hypothesis. The cause of the debate is often attributed to small sample sizes in combination with statistical tests for mean reversion that lackpower. In order to bypass this problem, we use the approach developed by Campbell and Viceira (2005) who have settled a vectorial autoregressive methodology (VAR) to measure the mean reversion of asset returns.The third chapter evaluates the speed of convergence of stock prices. A convenient way to characterize the speed of mean reversion is the half-life. Comparing the stock indexes of four developed countries (US, UK, France and Japan) during the period 1950-2014, we establish significant mean reversion, with a half-life lying between 4,0 and 5,8 years.The final chapter provides some results from a model built in order to study the linked impacts of demography and economy on the French pension scheme. In order to reveal the risks that are contained in pension fund investment, we use a Trending Ornstein-Uhlenbeck process instead of the typical GBM for modeling stock returns. We find that funded scheme returns, net of management fees, are slightly lower thanthe PAYG internal rate of return.

The South African white maize market is considered to be significantly more volatile than any other agricultural product traded on the South African Futures Exchange (SAFEX). This accentuates the need to effectively manage price risk, by means of hedging, to ensure a more profitable and sustainable maize production sector (Geyser, 2013:39; Jordaan, Grové, Jooste, A. & Jooste, Z.G., 2007:320). However, hedging at lower price levels might result in significant variation margins or costly buy–outs in order to fulfil the contract obligations. This challenge is addressed in this study by making use of technical analysis, focusing on the development of a practical and applicable composite technical indicator with the purpose of improving the timing of price risk management decisions identified by individual technical indicators. This may ultimately assist a producer in achieving a higher average hedge level compared to popular individual technical indicators. The process of constructing a composite indicator was commenced by examining the prevailing tendency of the market. By making use of the Directional Movement Index (DMI), as identified in the literature study, the market was found to continually shift between trending prices (prices moving either upwards or downwards) and prices trading sideways. Consequently, implementing only a leading (statistically more suitable for trading markets) or lagging (statistically more suitable for trending markets) technical indicator may generate false sell signals, as demonstrated by the application of these technical indicators in the white maize market. This substantiated the motivation for compiling a composite indicator that takes both leading and lagging indicators into account to more accurately identify hedging opportunities. The composite indicator made use of the Relative Strength Index (RSI) and Stochastic oscillator as leading indicators, and the Exponential Moving Average (EMA) and Moving Average Convergence Divergence (MACD) as lagging indicators. The results validated the applicability of such a composite indicator, as the composite indicator outperformed the individual technical indicators in the white maize market. The composite indicator achieved the highest average hedge level, the lowest average sell signals generated over the entire period, as well as the highest average hedge level as a percentage of the maximum price over the entire period. Hence, the composite indicator recognised hedging opportunities more accurately compared to individual technical indicators, which ultimately led to higher achieved hedging levels. / MCom. (Risk management), North-West University, Potchefstroom Campus, 2014