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The proposed resilience analysis methodology and its application to the SaskWater pumping stationGao, Fei 14 April 2010
Resilience engineering first appeared as a new approach for both system design and system safety in the last decade. One of the first substantive publications on resilience as applied to engineering was Resilience Engineering: Concepts and Precepts [Hollnagel et al. 2006]. Hollnagel, Woods, and Leveson developed the basic concepts behind resilience engineering in order to understand and prevent tragedies such as the Columbia Challenger accident and the September 11 terrorist attack.<p>
In its present stage, resilience engineering has several fundamental problems. 1. There is not an appropriate definition for resilience. 2. The differences between resilience and other similar concepts are not clarified. 3. There is no quantitative method which can measure resilience. The three questions need to be addressed in order to advance the concept of resilience engineering and form a theoretical concept to an applied science. These three issues then form the foundation of this thesis.<p>
As a first step, a resilience definition is presented based on the concepts of system function and damage. Then, the differences between resilience and five similar concepts (reliability, robustness, repairing, redundancy, and sustainability) are clearly elaborated. As a last step, a method for quantifying resilience is proposed in the form of a resilience index. This method exclusively measures system resilience by analyzing the system recoverability from two points of view: reconfiguration and replacement of components.<p>
In order to illustrate the approach to and definitions of resilience, an actual application is considered: a water pumping station operated by SaskWater in Saskatoon, Saskatchewan (the Clarence Booster Station). This pumping station is a complicated system consisting of mechanical electrical and chemical subsystems. The resilience of Clarence Booster Station is analyzed using the proposed definition of resilience and resilience index.<p>
This thesis is just an initial step establishing a comprehensive definition (qualitatively and quantitatively) for resilience. The resilience index so defined in this work appears to have potential but much more scrutiny and refinement must be pursued to ensure that it is truly applicable to more universal engineering applications.
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The proposed resilience analysis methodology and its application to the SaskWater pumping stationGao, Fei 14 April 2010 (has links)
Resilience engineering first appeared as a new approach for both system design and system safety in the last decade. One of the first substantive publications on resilience as applied to engineering was Resilience Engineering: Concepts and Precepts [Hollnagel et al. 2006]. Hollnagel, Woods, and Leveson developed the basic concepts behind resilience engineering in order to understand and prevent tragedies such as the Columbia Challenger accident and the September 11 terrorist attack.<p>
In its present stage, resilience engineering has several fundamental problems. 1. There is not an appropriate definition for resilience. 2. The differences between resilience and other similar concepts are not clarified. 3. There is no quantitative method which can measure resilience. The three questions need to be addressed in order to advance the concept of resilience engineering and form a theoretical concept to an applied science. These three issues then form the foundation of this thesis.<p>
As a first step, a resilience definition is presented based on the concepts of system function and damage. Then, the differences between resilience and five similar concepts (reliability, robustness, repairing, redundancy, and sustainability) are clearly elaborated. As a last step, a method for quantifying resilience is proposed in the form of a resilience index. This method exclusively measures system resilience by analyzing the system recoverability from two points of view: reconfiguration and replacement of components.<p>
In order to illustrate the approach to and definitions of resilience, an actual application is considered: a water pumping station operated by SaskWater in Saskatoon, Saskatchewan (the Clarence Booster Station). This pumping station is a complicated system consisting of mechanical electrical and chemical subsystems. The resilience of Clarence Booster Station is analyzed using the proposed definition of resilience and resilience index.<p>
This thesis is just an initial step establishing a comprehensive definition (qualitatively and quantitatively) for resilience. The resilience index so defined in this work appears to have potential but much more scrutiny and refinement must be pursued to ensure that it is truly applicable to more universal engineering applications.
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Metoda potlačení interferencí Wigenrovy-Villeovy distribuce / A Method to Supress Interferences in Wigner-Ville DistributionPikula, Stanislav January 2019 (has links)
The doctoral thesis focuses on signal representation in the time-frequency domain with constant resolution. In theoretical introduction the possibilities of displaying a signal in time and frequency are summarized. Attention is concentrated on comparison of short-time Fourier Transform (STFT) and Wigner-Ville Distribution (WVD). The latter achieves a significantly better resolution, especially for a linearly modulated signal. The disadvantage of WVD, which is the presence of interferences resulting from the calculation of the instantaneous autocorrelation function, is described in detail. These interferences are due to the presence of multiple components in the signal or its non-linear modulation. Subsequently, several methods are discussed, which can suppress these interferences, but at the cost of resolution loss. One of the interference suppression methods is smoothed pseudo Wigner-Ville distribution. It is further used in this thesis for the analysis of interference suppression when various filtrations in the time-frequency plane are applied. Several signals with multiple components or various non-linear modulations are used. Based on the analysis, a method using a set of variously smoothed pseudo Wigner-Ville distributions is designed to estimate the time-frequency representation with high resolution and minimal interferences. To compare the results to other methods, the quantitative metrics used in the literature are compared. To select the appropriate one a new metric is suggested. It is applicable to simulated signals and uses mean square error. Based on the comparison, the Stankovi\' measure is selected as the most appropriate for comparing results. The selected metric is used to determine the appropriate minimal number of differently smoothed pseudo Wigner-Ville distributions. Using the selected metric, the proposed method is compared with other methods. These are STFT with optimized window length, S-method with optimized parameter and optimization method using radial Gaussian kernel (RGK). These methods are compared based on the set of signals previously used for interference suppression analysis. In addition, noises are added to the signals. Finally, the methods are also compared based on the real bat echo signal. In conclusion, the proposed method outperforms the compared methods in suppressing interference and resolution.
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Développement d'un outil quantitatif mesurant la contagion émotionnelle chez des étudiants universitaires en psychoéducationSmart, Kaylee 08 1900 (has links)
La contagion émotionnelle se définit comme la tendance à imiter automatiquement les expressions non verbales avec celles des autres pour ainsi converger émotionnellement. Cette convergence peut être bénéfique si celui qui la reçoit sait comment la gérer en réalisant qu’il s’agit de l’émotion de l’autre, et non de la sienne. Toutefois, lorsqu’un intervenant perd le contrôle des effets de la contagion émotionnelle, il peut en résulter une détresse empathique. En travaillant auprès d’une clientèle en détresse, les intervenants représentent alors, eux aussi, un groupe à risque de vivre ces états émotionnels. Ainsi, connaitre sa vulnérabilité à la contagion émotionnelle serait un atout essentiel pour le travail et la santé psychologique des intervenants.
La contagion émotionnelle se mesure à partir d’un questionnaire autorapporté : le Emotional Contagion Scale (ECS). Cet outil présuppose que les personnes qui le remplissent connaissent bien leur réactivité émotionnelle aux émotions des autres. Cependant, ce n’est pas toujours le cas, puisque des travaux ont montré que les personnes peu conscientes de leurs émotions étaient plus à risque de difficultés à réguler leurs émotions. Ainsi, il nous apparait essentiel de développer un outil complémentaire et quantitatif afin de contourner les biais liés aux questionnaires autorapportés.
Le but de ce projet est de créer et d’évaluer un outil permettant une mesure comportementale de la contagion émotionnelle chez des étudiants universitaires en psychoéducation. Pour ce faire, nous avons mesuré automatiquement les réactions faciales des participants pendant qu’ils visionnaient un ensemble de stimuli vidéo suscitant diverses réactions émotionnelles. Les résultats indiquent que les deux instruments de contagion émotionnelle (quantitatif et autorapporté), ne semblent pas mesurer les mêmes construits psychosociaux, mais demeurent complémentaires. Aussi, le nouvel outil quantitatif de contagion émotionnelle permet de prédire le risque de présenter des symptômes dépressifs ainsi que de vivre certaines formes de stress chronique et d’épuisement professionnel chez les participants de l’étude. Les implications pour la recherche et la pratique sont discutées. / Emotional contagion is defined as the tendency to automatically mimic and synchronize facial expressions, vocalizations, postures and movements with those of another person’s and, consequently, to converge emotionally. This emotional convergence can be beneficial if one knows how to deal with it and realizes that it’s another person’s emotion, instead of his/her own. However, when one loses control over the effects of emotional contagion, it can cause empathic distress. By working with a clientele in distress, social workers are among the professionals who are the most at risk of experiencing emotional contagion. Thus, being aware of their own susceptibility to emotional contagion would be a way to prevent empathic distress, and to improve their professional work and personal well-being.
Emotional contagion is usually measured by a self-report questionnaire: The Emotional Contagion Scale (ECS). The ECS relies on the fact that people who use it are conscious of their emotional reactivity. However, it is not always the case. Previous research has shown that people who are unaware of their emotions are at risk of having problems with regulating their emotions. Therefore, it seems important to develop a complementary and quantitative measure of emotional contagion to counterbalance bias related to subjective measures.
The goal of this study is to develop and validate a behavioral measure of emotional contagion in a sample of psychoeducation students from the University of Montreal. To do so, we used a facial coding tool to automatically measure participants’ facial expressions as they watched emotion-eliciting film excerpts. Results indicate that both instruments of emotional contagion (quantitative and self-report) do not measure the same psychosocial constructs but remain complementary. Also, the new quantitative measure of emotional contagion seems to predict the risk of developing depressive symptoms and different forms of chronic stress and burnout among participants of this study. Implications for research and practice are discussed.
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