Parametry nahradniho obvodu synchronniho stroje znance ovlivnuji jeho chovani jak pri statickem provozu, tak predevsim pri nahlych dynamickych jevech a poruchovych stavech. Prace je zamerena na zhodnoceni dostupnych metod pro vypocet techto parametru pomoci Metody konecnych prvku. Prvni cast je venovana teoretickemu popisu zakladnich principu Metody Konecnych Prvku a jejich aplikaci na reseni problemu elektromagnetickeho pole v elektrickych strojich. Zaroven take shrnuje zakladni usporadani nahradniho obvodu synchroniho stroje, principi jeho konstrukce a zakladni funkci. Druha cast je venovana praktickemu vypoctu reaktanci nahradniho obvodu synchronniho stroje. S pomoci MKP jsou vypocteny synchronni reactance s uvazovanim vzajmeneho magnetickeho pusobeni proudu v d a q ose. Pro vypocet transientnich a subtransientnich reaktanci jsou navrzeny ctyri odlisne metody a jsou zhodnoceny z hlediska pozadovane presnosti vypoctu a narocnosti na vypocetni cas. Zaverecna cast popisuje zakladni merici metody pro urceni parametru nahrandniho obvodu na skutecnem stroji. Kapitola take obsahuje srovnani simulace trifazoveho zkratu synchronniho stroje s realnou zkouskou provedenou laboratorne. Zaver obsahuje srovnani jednotlivych metod a navrh optimalniho postupu pro vypocet zkoumanych parametru.

The thesis deals with the problematics of short-circuit current of synchronous machine. The first section focuses on the theoretical process of short-circuit current of synchronous machine and describes how this transient process changes throughout it's duration and with what reactances and time constants it is defined. Subsequently, this section deals with the methodics of tests of the snychronous machine,which may be used to set it's reactances. The second part of the work focuses on measurement of the short-circuit current in a specific synchronous machine. Further, there are measurements of processes of the short-circuit in time and their analysis. The last section of the thesis deals with the simulation of short-circuit current process. The simulation is ran by the Matlab/Simulink software. Simulated processes of short-circuit are then compared with the results of measurements from the previous section of the thesis.

No description available.

I projektet utreds möjligheterna kring att kunna kontrollera en generators reaktiva effektproduktion genom att styra magnetiseringsströmmen från en PLC. Som metod för styrning från PLC beslutades att en signal på 0-5V skulle användas. För att reglera magnetiseringen, och därmed i förlängningen den reaktiva effekten, beslutades att den befintliga manuella potentiometern skulle ersättas med två parallellkopplade digitala potentiometrar av typen MCP4261 som kontrollerades av en mikrokontroller. Att de digitala potentiometrarna skulle parallellkopplas beslutades efter en förstudie som visade på att det skulle resultera i en noggrannare reglering utan någon inskränkning på användbart reglerspann. Praktisk provning av mikrokontroller och digitala potentiometrar gav ett tillfredsställande och bra resultat med god upplösning. / This project investigates the possibilities of being able to control a generators reactive power production by controlling the excitation current from a PLC. As a method for controlling from PLC, it was decided that a signal of 0-5V should be used. In order to regulate the magnetization, and hence in the long term the reactive power, it was decided that the existing manual potentiometer would be replaced by two parallel-connected digital potentiometers of the type MCP4261 controlled by a microcontroller. The fact that the digital potentiometers would be connected in parallel was decided after a feasibility study which showed that in this way it would result in a more accurate regulation without any restriction on the usable control span. Practical testing of microcontrollers and digital potentiometers provided a satisfactory result with a good resolution.

La calidad de energía eléctrica incluye la calidad del suministro y la calidad de la atención al cliente. La calidad del suministro a su vez se considera que la conforman dos partes, la forma de onda y la continuidad. En esta tesis se aborda la continuidad del suministro a través de la localización de faltas. Este problema se encuentra relativamente resuelto en los sistemas de transmisión, donde por las características homogéneas de la línea, la medición en ambos terminales y la disponibilidad de diversos equipos, se puede localizar el sitio de falta con una precisión relativamente alta. En sistemas de distribución, sin embargo, la localización de faltas es un problema complejo y aún no resuelto. La complejidad es debida principalmente a la presencia de conductores no homogéneos, cargas intermedias, derivaciones laterales y desbalances en el sistema y la carga. Además, normalmente, en estos sistemas sólo se cuenta con medidas en la subestación, y un modelo simplificado del circuito. Los principales esfuerzos en la localización han estado orientados al desarrollo de métodos que utilicen el fundamental de la tensión y de la corriente en la subestación, para estimar la reactancia hasta la falta. Como la obtención de la reactancia permite cuantificar la distancia al sitio de falta a partir del uso del modelo, el Método se considera Basado en el Modelo (MBM). Sin embargo, algunas de sus desventajas están asociadas a la necesidad de un buen modelo del sistema y a la posibilidad de localizar varios sitios donde puede haber ocurrido la falta, esto es, se puede presentar múltiple estimación del sitio de falta.Como aporte, en esta tesis se presenta un análisis y prueba comparativa entre varios de los MBM frecuentemente referenciados. Adicionalmente se complementa la solución con métodos que utilizan otro tipo de información, como la obtenida de las bases históricas de faltas con registros de tensión y corriente medidos en la subestación (no se limita solamente al fundamental). Como herramienta de extracción de información de estos registros, se utilizan y prueban dos técnicas de clasificación (LAMDA y SVM). Éstas relacionan las características obtenidas de la señal, con la zona bajo falta y se denominan en este documento como Métodos de Clasificación Basados en el Conocimiento (MCBC). La información que usan los MCBC se obtiene de los registros de tensión y de corriente medidos en la subestación de distribución, antes, durante y después de la falta. Los registros se procesan para obtener los siguientes descriptores: a) la magnitud de la variación de tensión ( dV ), b) la variación de la magnitud de corriente ( dI ), c) la variación de la potencia ( dS ), d) la reactancia de falta ( Xf ), e) la frecuencia del transitorio ( f ), y f) el valor propio máximo de la matriz de correlación de corrientes (Sv), cada uno de los cuales ha sido seleccionado por facilitar la localización de la falta. A partir de estos descriptores, se proponen diferentes conjuntos de entrenamiento y validación de los MCBC, y mediante una metodología que muestra la posibilidad de hallar relaciones entre estos conjuntos y las zonas en las cuales se presenta la falta, se seleccionan los de mejor comportamiento.Los resultados de aplicación, demuestran que con la combinación de los MCBC con los MBM, se puede reducir el problema de la múltiple estimación del sitio de falta. El MCBC determina la zona de falta, mientras que el MBM encuentra la distancia desde el punto de medida hasta la falta, la integración en un esquema híbrido toma las mejores características de cada método. En este documento, lo que se conoce como híbrido es la combinación de los MBM y los MCBC, de una forma complementaria. Finalmente y para comprobar los aportes de esta tesis, se propone y prueba un esquema de integración híbrida para localización de faltas en dos sistemas de distribución diferentes. Tanto los métodos que usan los parámetros del sistema y se fundamentan en la estimación de la impedancia (MBM), como aquellos que usan como información los descriptores y se fundamentan en técnicas de clasificación (MCBC), muestran su validez para resolver el problema de localización de faltas. Ambas metodologías propuestas tienen ventajas y desventajas, pero según la teoría de integración de métodos presentada, se alcanza una alta complementariedad, que permite la formulación de híbridos que mejoran los resultados, reduciendo o evitando el problema de la múltiple estimación de la falta. / Power quality includes the supply and customer support quality. The supply quality considers two aspects, the wave shape and continuity. In this thesis the fault location problem, topic related with supply continuity is considered. Fault location is a relatively solved problem in power transmission systems, due to the homogeneous characteristics of the power line, measurements in both terminals and also the availability equipment such as fault locators normally included in distance relays. However, in power distribution systems the fault location is a complex problem which remains unsolved. The complexity is mainly because the presence of laterals, load taps, non homogeneous conductors, unbalances in the system and load. In addition, these power systems only have measurements at the substation and a simplified model of the power network. The main efforts to solve this problem have been oriented to the development of impedance based methods. Because of the reactance estimation makes possible the estimation of the distance to the faulted node by using the circuit model, those methods are considered as Model Based Methods (MBM). However the main drawbacks are related to the requirement of a good system model and to the possibility of multiple estimation of the location of the fault due to the three-shape of such networks. As a result, in this thesis an analysis and a comparative test between several MBM frequently cited is presented. In addition, the solution of the fault location is complemented by using methods which use more than the rms values of current and voltage obtained from fault databases. As tool to relate this information with the fault location, two classification techniques are used and tested (LAMDA and SVM). These relate the voltage and current characteristics to the faulted zone and are denoted in this document as Classification Methods Based on the Knowledge (CMBK).The information used by CMBK is obtained from current and voltage fault registers measured at the distribution substation, before, during and after the fault. These registers are pre-processed to obtain the following characteristics or descriptors: a) The magnitude of the voltage variation between the steady states of fault and pre-fault ( dV ), b) the magnitude of the current variation between the steady states of fault and pre-fault ( dI ), c) the magnitude of the apparent power variation between the steady states of fault and pre-fault ( dS ), d) the magnitude of the reactance as seen from the substation ( Xf ), e) the frequency of the transient caused by the fault ( f ), and f) the maximum eigenvalue of the correlation matrix of the currents ( Sv ). By using these descriptors, several training and validation sets were used with CMBK and by means of a proposed methodology it is shown how to relate these sets with the faulted zone and also to select those which offer the best performances.The application results demonstrate how by combining the MBM with the CMBK it is possible to reduce the multiple estimation of the fault location. The CMBK is used to determine the faulted zone while the MBM finds the distance from the measurement point to the faulted node. Thus the integration in a hybrid approach uses the best characteristics of each method. In this document, the term hybrid is used to describe the complementary combination of MBM and CMBK. Finally and aimed to compare the thesis results, an integration hybrid scheme to fault location is proposed and tested in two different power distribution systems. Both, methods which use the system parameters and are based on the impedance estimation (MBM), and those which use the information represented by the signal descriptors and are based in classification techniques (CMBK) have shown the capability to solve the problem of fault location. The two proposed methodologies have advantages and drawbacks, but according to the integration theory presented, high complementarity has been reached. This makes possible the development of a hybrid approach used to avoid or reduces the multiple estimation of the fault location.

Thesis (M.A.)--Miami University, Dept. of Psychology, 2009. / Title from first page of PDF document. Includes bibliographical references (p. 43-47).

Submitted by Bruna Oliveira (brunamiyuki@gmail.com) on 2017-08-29T17:05:38Z No. of bitstreams: 1 Tese_versãofinal.pdf: 3842360 bytes, checksum: 086bcf268fcb7702a198316e866fa6a2 (MD5) / Approved for entry into archive by Pamela Beltran Tonsa (pamela.tonsa@fgv.br) on 2017-08-29T19:48:14Z (GMT) No. of bitstreams: 1 Tese_versãofinal.pdf: 3842360 bytes, checksum: 086bcf268fcb7702a198316e866fa6a2 (MD5) / Made available in DSpace on 2017-08-30T13:07:01Z (GMT). No. of bitstreams: 1 Tese_versãofinal.pdf: 3842360 bytes, checksum: 086bcf268fcb7702a198316e866fa6a2 (MD5) Previous issue date: 2017-07-31 / A privacidade de informações na internet é uma das maiores preocupações advindas da ascensão da web 2.0. Entretanto, cada vez é mais comum a requisição e manejamento de dados pessoais por empresas que, por meio de Sistemas de Recomendação (SR), visam garantir aos usuários serviços ou produtos personalizados às suas necessidades. Porém, frequentemente os consumidores enfrentam um paradoxo de privacidade-personalização, pois precisam conceder informações, mas temem como elas serão utilizadas pelas empresas. O uso incoerente de tais dados pode dar ao indivíduo a sensação de que sua liberdade está sendo cerceada, levando-o a reagir de maneira diversa da intenção do sistema. Trata-se, efetivamente, de um efeito bumerangue, entendido como uma resposta oposta à ameaça de sua liberdade na web. Tendo em vista que a literatura de SI explora de maneira insuficiente os efeitos da percepção de intrusão na disposição em revelar informações, sobretudo por meio da teoria da reatância psicológica – de onde advém o efeito bumerangue – o objetivo desta pesquisa foi verificar como a percepção dos usuários sobre a intrusão do Sistema de Recomendação pode afetar a sua disposição em revelar suas informações. Foram realizados dois experimentos, sendo um nos Estados Unidos e outro no Brasil, com amostras válidas de 213 e 237 participantes, respectivamente. Para isto, foi desenvolvido um protótipo de Sistema de Recomendação Experimental na plataforma Qualtrics. As técnicas utilizadas para análise de dados foram a análise de variância de um fator (one-way ANOVA) e a análise de covariância (ANCOVA). Dentre os resultados obtidos, demonstrou-se o efeito bumerangue do SR, pois quanto maior o nível de intrusão do SR, menor a disposição para revelar suas informações; verificou-se a existência de apenas dois níveis de intrusão percebida pelo usuário; foi constatado o impacto das preocupações de privacidade na internet na relação entre percepção de intrusão e disposição em revelar suas informações, além da uniformidade no comportamento entre as duas amostras. Com base nos resultados, espera-se que desenvolvedores de SR e empresas que os utilizam evitem futuros efeitos bumerangue em suas recomendações, o que afugentaria um potencial cliente. / Information privacy on internet is one of the biggest concerns that arise with web 2.0. However, it is increasingly common for companies that use Recommendation Systems (RS) the request and manage of personal data aiming to guarantee personalized services or products to the users. However, consumers often face a privacy-personalization paradox because they need to provide information, but fear how companies will use it. Incoherent use of such data can give to the individual the feeling that their freedom is being curtailed, causing reactions differently than the system’s intention. It is a boomerang effect, understood as an opposed response to the threat of its freedom on the web. Considering that the IS literature insufficiently explores the effects of the perception of intrusion on the willingness to disclose information, especially through the theory of psychological reactance – where the boomerang effect comes from – the objective of this research is to verify how the users' perception of the intrusion of the Recommendation System may affect your willingness to disclose your information. Two experiments were conducted in the United States and Brazil, with valid samples of 213 and 237 participants, respectively. A prototype of an Experimental Recommendation System (ERS) was developed on the Qualtrics platform. The techniques used for data analysis were the analysis of one-way variance (one-way ANOVA) and covariance analysis (ANCOVA). Among the results, the boomerang effect of RS was demonstrated, because the higher the level of SR intrusion, the less is the willingness to disclose its information. It was verified the existence of only two levels of intrusion perceived by the user. The impact of Internet privacy concerns on the relationship between perception of intrusion and willingness to disclose information was verified, as well as the behavioral indifference between the two samples. Based on the results, RS developers and companies that use them are expected to avoid future boomerang effects in their recommendations, which would scare away a potential customer.

A prévention de l'anorexie, et plus largement des troubles de comportement alimentaire, revêt un intérêt social et sociétal fort. Elle comporte également un intérêt académique, ce contexte étant sous-représenté en recherche. Les communications existantes sur la prévention de l'anorexie utilisent la stratégie de l'appel à la peur, malgré une littérature non consensuelle sur le niveau d'appel à adopter et sur le fonctionnement exact du mécanisme. La littérature propose également, pour expliquer l'échec de l'appel à la peur, l'existence d'une réactance situationnelle, sans que celle-ci n'ait jamais été validée. Quatre expérimentations auprès de jeunes femmes étudiantes, public particulièrement sensible dans ce contexte, permettent de comprendre et valider le fonctionnement de l'appel à la peur par médiations successives et en intégrant la réactance situationnelle. Il est montré que le message avec appel à la peur crée un état cognitivo-émotionnel composé de peur et de sévérité perçue qui vont influer de manière opposée sur la réactance situationnelle. Cette dernière influence à son tour la perception d'efficacité de la recommandation, qui déterminera ensuite le succès ou l'échec du message. En parallèle, le rôle médiateur, mais secondaire, de l'auto-efficacité sur l'efficacité perçue de la recommandation est révélé, de même que celui modérateur de la vulnérabilité perçue. En complément de ce résultat, chacune des études s'attache à manipuler, en plus du niveau d'appel à la peur, différentes composantes et caractéristiques du message, dont les effets sur le mécanisme d'appel à la peur permettent de résoudre, en partie, certains conflits existants dans la littérature. Ainsi, le rôle des composantes, visuelle et verbale, sur le niveau ressenti de peur est examiné (études 1 et 2). L'effet de la formulation de la recommandation (étude 2), de même que l'effet du type d'argument (étude 3) sur le processus de l'appel à la peur sont analysés. Enfin, l'ajout du dégoût à l'appel à la peur et la validation du fonctionnement du processus par une mesure comportementale affinent encore la compréhension des mécanismes d'action de l'appel à la peur (étude 4). Pour conclure, les clés d'une communication préventive de l'anorexie efficace avec recours à l'appel à la peur sont données et les résultats discutés et complétés par des voies de recherche possibles, dont certaines permettent de pallier les limites mentionnées pour la présente recherche. / Anorexia prevention or more widely disorder eating behavior, has a strong social and societal interest. It also presents an academic interest, since this context is under-represented in research. Existing anorexia prevention campaigns use the strategy of fear appeal, despite a non-consensual literature on the level of fear appeal to adopt and the exact functioning of the mechanism. The existing literature also suggests, to explain failure of fear appeal, that there is a situational reactance, even though this has never been validated. Four experiments on young women students, public particularly sensitive to this context, allow us to understand and validate the mechanism of fear appeal in successive mediations and while integrating situational reactance. Through these experiments, it is shown that the message with fear appeal creates a cognitive and emotional state of fear, and perceived severity that will oppositely influence situational reactance. The latter influences the perceived efficacy of recommendation, which in turn determines the success or failure of the message. In parallel, the mediator, but secondary role, of self-efficacy on the perceived efficacy of the recommendation is revealed, as well as the moderator of perceived susceptibility. Furthermore, each study attempts to handle, in addition to the level of fear appeal, various components and characteristics of the message, whose effects on the fear appeal mechanism solve in part, some existing conflicts in the literature. Thus, the role of the components, visual and verbal, on the level of fear felt is examined (studies 1 and 2). The effect of the wording of the recommendation (study 2), as well as the effect of the type of argument (study 3) on the process of fear appeal are analyzed. Finally, the addition of the disgust on fear appeal and the validation process by a behavioral measure yet refine understanding the mechanism of fear appeal (study 4). To conclude, the key preventive effective communication with anorexia use of fear appeals are given and results are discussed and complemented with possible future research directions, some of which are used to overcome the limitations mentioned on this research.

No description available.

「拖延」意指個體對應該且必須要做的事情，延遲開始、延遲結束或集中到最後一刻才完成的行為。本研究從內控人格特質與拖延間的不一致結果切入探討，提出兩個可能的影響因素：心理抗拒感與成就動機。研究一採問卷施測，內控人格特質越強者，心理抗拒感傾向越高，拖延傾向亦較高，支持以心理抗拒感觀點切入探討拖延行為；在成就動機方面，未得到內控人格特質透過兩種取向成就動機預測拖延的結果。研究二加入努力與智力本質觀概念，再次驗證研究一內控人格特質、心理抗拒感與拖延傾向的關係；此外，研究二採用實驗法探討高抗拒狀態是否會有較高的拖延行為。然而研究二發現受試者對操弄引發的認知與情緒反應不一，採用內部分析，根據操弄檢核分數重新區分生氣情緒與認知自由高低分組，挑選最符合與最不符合抗拒狀態概念的兩組（高生氣情緒、低認知自由／低生氣情緒、高認知自由）進行分析，結果並未支持抗拒狀態越高，拖延行為亦越高的假設。重新檢視心理抗拒感理論，加入基本能力為新分組變數，以2（認知自由高低）× 2（生氣情緒高低）× 2（基本能力高低）三因子受試者間設計進行分析。結果顯示生氣情緒與認知自由可能扮演不同的角色，生氣情緒提供個人展現某些行為的動力，認知自由表示個人知覺自由的程度，而個人基本能力的表現則受到情境的影響。生氣情緒與認知自由的交互作用顯示能力高低的差異展現在高生氣情緒、高認知自由與低生氣情緒、低認知自由的情況中，高生氣情緒、低認知自由時，能力越高越早開始越早結束，且較不會延遲結束；低生氣情緒、低認知自由時，基本能力低者可能因預期較差的表現，因此晚點開始較愉悅的想法較高，較晚結束作業，也較易延遲結束。高低基本能力者在另外兩種情境無顯著差異；高生氣情緒、低認知自由時，可能因為即使生氣情緒提供行為動力，但主觀自由低，使能力高者並未發揮其能力而無顯著差異；低生氣情緒、高認知自由時，雖主觀自由高但可能因為缺乏展現行為的動力，高低能力者行為表現相似。總結來說，本研究以心理抗拒感觀點貫穿研究一與研究二，研究一發現內控人格特質高者，有較高的心理抗拒感傾向，而有較高的拖延傾向。研究二除驗證研究一發現外，另顯示抗拒狀態的情緒與認知層面具有不同的影響與作用，且視個人基本能力的不同而有表現的差異。此發現有助於深入理解心理抗拒感概念，並為心理抗拒感理論提出一小步的進展與突破。