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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.
11

Diretrizes para um sistema de medição de desempenho para empresas do ramo madeireiro da região amazônica norte mato-grossense : estudo multicasos

Fedato, Geovana Alves de Lima 07 October 2010 (has links)
Made available in DSpace on 2016-06-02T19:51:46Z (GMT). No. of bitstreams: 1 3310.pdf: 3654714 bytes, checksum: 8f5412389b554170e561ec7fca521015 (MD5) Previous issue date: 2010-10-07 / This work assumes that to effectively manage business activities, a form of control and monitoring is necessary, whether by means of indicators, or in a more advanced situation, by means of a performance measurement process that is suitable to the company s reality. Thus, the objective of this study is to establish guidelines for develop a performance measurement system, capable of assisting the peculiarities and organizational needs of control and strategies for companies in the wood sector in the city of Sinop, in Mato Grosso, Brazil. Companies currently face several challenges, because they need to thrive in a highly competitive environment, concomitantly meeting the needs and expectations of multiple stakeholders. This paper addresses the importance of environmental and social variables, which are currently increasing and whose reflexes on the organization are no longer latent but obvious. The method used to achieve the goals was the multiple case study with a qualitative approach, which enabled to identify the companies selected, and from this reality, to establish guidelines for develop a performance measurement system for two scenarios, was first proposed for the method of Rouse e Putterill (2003) for companies without an adequate infrastructure to measure performance. The second applies the Performance Prism framework by Neely et al. (2002) for companies with more suitable infrastructure for the development of a system performance measurement more robust. In all the companies of the scenario, social and environmental issues can be included, hence representing the reality under study in a clearer manner. The contribution the academy is conducted to compare the characteristics of performance measurement and management infrastructure, already contributing to the logging companies was made to suggest ways to control and evaluation of activities that respect the maturity of the management and peculiarities of each. / Este trabalho parte da premissa que, para efetivamente haver gerenciamento das atividades do negócio, é necessária uma forma de controle e acompanhamento, seja por meio de indicadores ou, numa situação mais avançada, um sistema de medição de desempenho adequado à realidade da empresa. Assim, tem-se como objetivo estabelecer diretrizes para o desenvolvimento de um sistema de medição de desempenho, capaz de atender às peculiaridades e necessidades organizacionais de controle e estratégias das empresas do setor madeireiro na cidade de Sinop, no estado do Mato Grosso. Atualmente, há vários desafios para essas empresas, pois, num ambiente altamente competitivo, precisam prosperar, atendendo de forma concomitante, aos anseios dos mais diversos stakeholders. Este trabalho tem a preocupação de retratar a importância das variáveis ambientais e sociais que aumentam gradativamente e cujos reflexos na organização deixam de ser latentes e passam a ser evidentes. O método utilizado para atingir os objetivos foi o estudo de caso múltiplo com abordagem qualitativa, que permitiu conhecer as empresas selecionadas, para, a partir desta realidade, estabelecer as diretrizes para o desenvolvimento de formas de medição de desempenho para dois cenários: para o primeiro foi proposto o método de Rouse e Putterill (2003) para empresas sem uma infraestrutura adequada à medição de desempenho; para o segundo foi proposto o Performance Prism de Neely et al. (2002) para empresas com infraestrutura mais apropriada, sendo possível o desenvolvimento de um sistema de medição de desempenho mais robusto. Em ambos, a questão social e ambiental pode ser incluída, retratando melhor a realidade em estudo. A contribuição à academia é realizada ao relacionar as diretrizes características da medição de desempenho e a infraestrutura de gestão. Já a contribuição para as empresas madeireiras foi efetuada ao sugerir formas de controle e avaliação das atividades que respeitem a maturidade e peculiaridades da gestão de cada uma.
12

Analýza vybraných metod zřizování a měření prostorové polohy koleje / Analysis of selected methods for setting and measuring the spatial position of track

Karásek, Jakub January 2012 (has links)
The aim of the work is to compare different ways of measuring geometric parametrs of railway track and compare methods for guidance automatic tamping machine in estabilishing the geometrical parameters of the selected track section between train stations Brodek u Přerova - Grygov. The work contains a description of the superstructure gauging carriage and measuring system APK, whose data were used to compare the track geometry and its spatial position during the observation period. Conclusion of the work includes an assessement of individual measurements and recommendations for practise.
13

Decentralizovaný systém řízení vytápění budov / DCS for building control

Kopeček, Petr January 2008 (has links)
This thesis deals with DCS for bulding control. The main aim was to develop a general system, which can be adapted according to the individual requirements and which should minimize costs too. Hardware modules, communication bus, communication protocol, system topology and regulation mechanisms, have been designed. Regulators have been set. There are introduced current realization and possible future extensions too. The high security and the high functionality topics are included.
14

Workload Adaptive Cruise Control

Hajek, Wilfried 13 May 2015 (has links)
This doctoral thesis focuses on the modification of ACC to include actual driver workload in the context of automatic headway change. ACC is a driver assistance system that automatically maintains a preliminary defined speed and permits a driver to perform manual headway changes. As drivers show worse (brake) reaction times under high workload situations, the system increases headway accordingly. Driver workload is estimated based on physiological data. Here, we investigate the possibilities of such a system, assuming that physiological sensors can be implemented in future vehicles. The thesis consists of three parts: In the first part, the theoretical background is described and a suitable theoretical model is developed; in the second part, experiments are described, and in the last part, results are discussed. Altogether four experiments support this thesis: 1. The first experiment investigates the foundational relationships between physiology, brake reaction time and workload level. The study employs a simulator setting and results show that physiological data, such as heart rate and skin conductance, permit the identification of different workload levels. These findings validate the results of other studies showing that workload leads to an increase in reaction time. These results could only be validated between the extremes “no-workload” and “high workload” situations. 2. The second experiment simulates an ideal workload-adaptive cruise control (WACC) system. In a simulator setting, system acceptance and awareness are studied, with a view toward future implementation in a real car. The results show better acceptance of WACC in comparison with ACC when subjects receive additional information about the new system. This is because subjects do not perceive changes in distance under high workload conditions. 3. The third experiment focuses on acceptance of the simulated system in on-road conditions. In this study, WACC is integrated in the car and is operated using a MATLAB model. The experiment shows that more subjects notice changes in distance in the on-road condition. In general WACC is preferred over ACC; it is especially these subjects who do not notice changes in distance, who value WACC more than ACC. With the aim of implementing an operational WACC that is capable of adjusting distance according to changes in physiological data, a workload algorithm is developed. 4. The fourth experiment validates the workload algorithm. Results of the algorithm are compared with recordings of the activated workload task and detection rate is calculated. The detection of workload periods was feasible in nearly every case and detection rate was favorable, especially if one considers lags due to design-related latency periods. The experiments presented here indicate that workload is detectable in physiological data and that it influences brake reaction time. Further, we provide evidence pointing to the technical possibility of implementing WACC as well as positive acceptance. The results have been published as an article and are part of this thesis. Also, some parts of the thesis are published as a book chapter (see footnotes). Another publication is in preparation, coauthored by diploma thesis students, who are supervised by the author (consult footnotes). This dissertation is composed, in part, of these publications. References to page numbers of the diploma theses are given to ensure correspondence. The author escorted the topic WACC from the beginning to the end. Sometimes students were involved and intensively supervised, from a thematic as well as a personnel guidance perspective. The author planned the whole project and executed studies and calculations. His psychology insights were not only limited to the discipline of psychology but were furthermore, with the help of students, interdisciplinarily expanded to the subject of informatics. Every study and every result which is presented within this work, was conducted or achieved by the author or (if students supported him) was discussed with the author in weekly discussions (and often several times a day). In these discussions the author provided new ideas and corrections if necessary. Apart from that, the author looked after the fulfillment of the central theme, implemented his psychological knowledge on a daily basis and provided his expertise to complement interdisciplinary point of views. He discussed the central theme as well as details with external partners like the MIT AgeLab as well as professors of the European Union from the adaption project (a project aimed at educating future researchers which includes involvement of highly important commercial and educational partners) and beyond. In this time he also visited conferences and accumulated knowledge which led to the successful achievements of the main objective and he was relevant in reaching the common goals of the adaption project. Furthermore he presented the results of the scientific work on a conference, workshops and in written publications. Within BMW Group Research and Technology, he identified important department- and project- partners and combined the knowledge to a result which benefits science and economy.:1 Introduction 2 Goal And Research Questions 3 Theoretical And Empirical Background 3.1 Theoretical Model 3.2 Workload Measurement over Physiology 3.3 Secondary Task: The N-Back Task 4 Forward Collision Warning Experiment 4.1 Introduction and Objectives 4.2 Method 4.3 Procedure 4.4 Results 4.5 Discussion and Conclusion 5 Workload-adaptive cruise control - A new generation of advanced driver assistance systems 5.1 Introduction 5.2 Material 5.3 Measurements 5.4 The Secondary Task: N-Back Task 5.5 WACC system 5.6 Procedure 5.7 Results 5.8 Discussion and conclusion 6 On-Road Study Of The Simulated WACC 6.1 Introduction and Objectives 6.2 Method 6.3 Results 6.4 Discussion and conclusion 7 Online detection of workload in an on-road setting 7.1 Introduction and objectives 7.2 Method 7.3 Results 7.4 Discussion and conclusion 8 General discussion 8.1 Background and chosen approach 8.2 Summary of findings 8.3 Discussion and conclusion 9 References / In dieser Dissertation wird eine Abwandlung des Active Cruise Control (ACC) untersucht, das zusätzlich die Belastung (Workload) des Fahrers als Parameter betrachtet, um den Abstand zum Vordermann automatisiert zu verändern. Bei diesem ACC handelt es sich um ein Fahrerassistenzsystem, das automatisiert die eingestellte Geschwindigkeit hält und eine manuelle (durch den Nutzer ausgelöste) Abstandsveränderung zum Vordermann ermöglicht. Da sich die Bremsreaktionszeit von Fahrern in hohen Belastungssituationen verschlechtert, soll das entwickelte Workload-adaptive Cruise Control (WACC) in Situationen hoher Belastung den Abstand zum Vordermann automatisiert erhöhen. Die Belastung des Fahrers soll durch physiologische Daten ermittelt werden. Die vorliegende Arbeit untersucht die Möglichkeit eines solchen Systems unter der Annahme, dass in Zukunft geeignete physiologische Sensoren ins Auto eingebaut werden können. Die Arbeit besteht aus drei Teilen: • Im ersten Teil wird der theoretische Hintergrund beschrieben und ein passendes theoretisches Modell entwickelt. • Im zweiten Teil werden die durchgeführten Experimente beschrieben. • Im dritten Teil werden die Ergebnisse diskutiert. Insgesamt wurden im Rahmen dieser Arbeit vier Experimente durchgeführt: Das erste Experiment beschäftigte sich mit den grundlegenden Zusammenhängen zwischen Physiologie, Bremsreaktionszeit und Belastungslevel. Wie die Ergebnisse der im Simulator durchgeführten Studie zeigen, können mit physiologischen Daten wie Herzrate, Herzratenvariabilität und Hautleitfähigkeit unterschiedliche Workloadlevel identifiziert werden. Darüber hinaus wurden die Ergebnisse anderer Studien bestätigt, die belegen, dass Workload die Bremsreaktionszeit erhöht, wobei dies nur im Kontrast zwischen den Extrembereichen „kein Workload“ und „hoher Workload“ nachweisbar ist. Das zweite Experiment diente der Simulierung eines perfekten WACC. Im Simulator wurden Akzeptanz und Systemwahrnehmung getestet, um vor der Implementierung in ein Realfahrzeug weitere Erkenntnisse zu gewinnen. Im Vergleich zum ACC wurde das WACC von den Probanden besser akzeptiert, nachdem sie zusätzliche Informationen zum neuen System erhalten hatten. Der wesentliche Grund dafür ist, dass die Probanden ohne Informationen die Abstandsveränderung bei hohem Workload nicht realisieren. Das dritte Experiment fokussierte auf die Akzeptanz des simulierten Systems unter Realbedingungen. Das WACC wurde in das Auto integriert und durch ein MATLAB Modell gesteuert. Als Ergebnis zeigte sich, dass unter Realbedingungen mehr Probanden die Abstandsveränderung realisieren als im Simulator. Generell wird das WACC präferiert – vor allem jene Probanden, die die Abstandsveränderung nicht realisieren, bewerten das WACC besser als das ACC. Mit den in diesem Teilexperiment erhobenen Daten wurde ein Algorithmus zur Workloaderkennung entwickelt. Auf dieser Basis konnte im letzten Experiment ein Realsystem implementiert werden, das aufgrund physiologischer Daten den Abstand verändert. Das vierte Experiment beschäftigte sich mit der Validierung des Algorithmus zur Workloaderkennung. Die Ergebnisse des Algorithmus wurden mit der aufgezeichneten Aktivierung des Workloadtasks verglichen und eine Detektionsrate ermittelt. Die Detektion der Workloadperioden gelingt in fast allen Fällen und die Detektionsrate ist vielversprechend, gerade wenn man Verzögerungen berücksichtigt, die wegen der Latenzzeit körperlicher Reaktionen nicht verbesserungsfähig sind. In den vorliegenden Experimenten konnte gezeigt werden, dass Workload über die Physiologie messbar ist und sich auf die Bremsreaktionszeit auswirkt. Darüber hinaus wurde gezeigt, dass ein WACC technisch machbar ist und die Ergebnisse lassen außerdem auf eine hohe Akzeptanz schließen. Die Forschungsergebnisse wurden in einem Artikel publiziert, der auch in dieser Dissertation zu finden ist. Teile der vorliegenden Arbeit wurden außerdem als Buchkapitel veröffentlicht (siehe Fußnoten), eine weitere Publikation mit den vom Autor umfassend betreuten Diplomanden ist in Ausarbeitung. Um die Nachvollziehbarkeit zu gewährleisten, wurde auf die Seitenzahlen der entsprechenden Diplomarbeiten verwiesen. Als Autor dieser Dissertation habe ich das Thema WACC von Anfang bis Ende selbst erarbeitet bzw. wurden Studenten eingesetzt und angeleitet, wo es sinnvoll erschien. Neben der fachlichen wie personellen Führung der Studenten umfassten meine Aufgaben die Planung des Gesamtprojekts, das Durchführen der Studien und die Berechnung von Kennzahlen – sowohl in meinem eigenen psychologischen Fachgebiet als auch interdisziplinär mit Hilfe von Experten aus der Informatik. Jedes Ergebnis, das in dieser Arbeit präsentiert wird, wurde entweder von mir selbst erzielt oder – sofern ich dabei von Studenten unterstützt wurde – mit mir in wöchentlichen (oft auch mehrmals täglich stattfindenden Meetings) besprochen. Wichtig war mir als Autor, einen durchgängigen Weg zur Entwicklung eines WACC zu wahren, mein psychologisches Fachwissen täglich anzuwenden und in interdisziplinären Aufgaben und Diskussionen meine Perspektive einzubringen. Besonders wichtig war dabei die Diskussion des Gesamtprojekts und der Details mit externen Partnern wie dem MIT AgeLab oder Professoren aus der Europäischen Union im Rahmen des Adaptation Projekts (ein von der EU gefördertes Projekt zur Ausbildung von Forschern, unter Einbindung wirtschaftlich und wissenschaftlich hochrangiger Partner). Durch die Präsentation der Ergebnisse auf Konferenzen, in Workshops und Publikationen konnte ich einen Beitrag dazu leisten, um die Adaptation-Ziele zu erreichen. Innerhalb der BMW Group Forschung und Technik habe ich darauf geachtet, relevante Schnittstellen- und Projektpartner zu identifizieren und das erlangte Wissen zu einem Ergebnis zu verbinden, das Wissenschaft und Wirtschaft gleichermaßen nützt.:1 Introduction 2 Goal And Research Questions 3 Theoretical And Empirical Background 3.1 Theoretical Model 3.2 Workload Measurement over Physiology 3.3 Secondary Task: The N-Back Task 4 Forward Collision Warning Experiment 4.1 Introduction and Objectives 4.2 Method 4.3 Procedure 4.4 Results 4.5 Discussion and Conclusion 5 Workload-adaptive cruise control - A new generation of advanced driver assistance systems 5.1 Introduction 5.2 Material 5.3 Measurements 5.4 The Secondary Task: N-Back Task 5.5 WACC system 5.6 Procedure 5.7 Results 5.8 Discussion and conclusion 6 On-Road Study Of The Simulated WACC 6.1 Introduction and Objectives 6.2 Method 6.3 Results 6.4 Discussion and conclusion 7 Online detection of workload in an on-road setting 7.1 Introduction and objectives 7.2 Method 7.3 Results 7.4 Discussion and conclusion 8 General discussion 8.1 Background and chosen approach 8.2 Summary of findings 8.3 Discussion and conclusion 9 References
15

POLYNOMIAL CURVE FITTING INDICES FOR DYNAMIC EVENT DETECTION IN WIDE-AREA MEASUREMENT SYSTEMS

Longbottom, Daniel W. 14 August 2013 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / In a wide-area power system, detecting dynamic events is critical to maintaining system stability. Large events, such as the loss of a generator or fault on a transmission line, can compromise the stability of the system by causing the generator rotor angles to diverge and lose synchronism with the rest of the system. If these events can be detected as they happen, controls can be applied to the system to prevent it from losing synchronous stability. In order to detect these events, pattern recognition tools can be applied to system measurements. In this thesis, the pattern recognition tool decision trees (DTs) were used for event detection. A single DT produced rules distinguishing between and the event and no event cases by learning on a training set of simulations of a power system model. The rules were then applied to test cases to determine the accuracy of the event detection. To use a DT to detect events, the variables used to produce the rules must be chosen. These variables can be direct system measurements, such as the phase angle of bus voltages, or indices created by a combination of system measurements. One index used in this thesis was the integral square bus angle (ISBA) index, which provided a measure of the overall activity of the bus angles in the system. Other indices used were the variance and rate of change of the ISBA. Fitting a polynomial curve to a sliding window of these indices and then taking the difference between the polynomial and the actual index was found to produce a new index that was non-zero during the event and zero all other times for most simulations. After the index to detect events was chosen to be the error between the curve and the ISBA indices, a set of power system cases were created to be used as the training data set for the DT. All of these cases contained one event, either a small or large power injection at a load bus in the system model. The DT was then trained to detect the large power injection but not the small one. This was done so that the rules produced would detect large events on the system that could potentially cause the system to lose synchronous stability but ignore small events that have no effect on the overall system. This DT was then combined with a second DT that predicted instability such that the second DT made the decision whether or not to apply controls only for a short time after the end of every event, when controls would be most effective in stabilizing the system.
16

Electric utility planning methods for the design of one shot stability controls

Naghsh Nilchi, Maryam 12 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Reliability of the wide-area power system is becoming a greater concern as the power grid is growing. Delivering electric power from the most economical source through fewest and shortest transmission lines to customers frequently increases the stress on the system and prevents it from maintaining its stability. Events like loss of transmission equipment and phase to ground faults can force the system to cross its stability limits by causing the generators to lose their synchronism. Therefore, a helpful solution is detection of these dynamic events and prediction of instability. Decision Trees (DTs) were used as a pattern recognition tool in this thesis. Based on training data, DT generated rules for detecting event, predicting loss of synchronism, and selecting stabilizing control. To evaluate the accuracy of these rules, they were applied to testing data sets. To train DTs of this thesis, direct system measurements like generator rotor angles and bus voltage angles as well as calculated indices such as the rate of change of bus angles, the Integral Square Bus Angle (ISBA) and the gradient of ISBA were used. The initial method of this thesis included a response based DT only for instability prediction. In this method, time and location of the events were unknown and the one shot control was applied when the instability was predicted. The control applied was in the form of fast power changes on four different buses. Further, an event detection DT was combined with the instability prediction such that the data samples of each case was checked with event detection DT rules. In cases that an event was detected, control was applied upon prediction of instability. Later in the research, it was investigated that different control cases could behave differently in terms of the number of cases they stabilize. Therefore, a third DT was trained to select between two different control cases to improve the effectiveness of the methodology. It was learned through internship at Midwest Independent Transmission Operators (MISO) that post-event steady-state analysis is necessary for better understanding the effect of the faults on the power system. Hence, this study was included in this research.

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