This thesis presents a real-time autonomous guidance and control method for a quadrotor in a GPS-denied environment. The quadrotor autonomously seeks a destination while it avoids obstacles whose shape and position are initially unknown. We implement the obstacle avoidance and destination seeking methods using off-the-shelf sensors, including a vision-sensing camera. The vision-sensing camera detects the positions of points on the surface of obstacles. We use this obstacle position data and a potential-field method to generate velocity commands. We present a backstepping controller that uses the velocity commands to generate the quadrotor's control inputs. In indoor experiments, we demonstrate that the guidance and control methods provide the quadrotor with sufficient autonomy to fly point to point, while avoiding obstacles.

Mathematical models are used in engineering and the sciences to estimate properties of systems of interest, increasing our understanding of the surrounding world and driving technological innovation. Unfortunately, as the systems of interest grow in complexity, so to do the models necessary to accurately describe them. Analytic solutions for problems with such models are provably intractable, motivating the use of approximate yet still accurate estimation techniques. Particle filtering methods have emerged as a popular tool in the presence of such models, spreading from its origins in signal processing to a diverse set of fields throughout engineering and the sciences including medical research, economics, robotics, and geophysics. In groundwater hydrology, a key component of aquifer assessment is the determination of the properties which permit water resource managers to estimate aquifer drawdown and safe yield. Presented is a particle filtering approach to estimate aquifer properties from transient data sets, leveraging recently published analytically-derived models for confined aquifers. The approach is examined experimentally through validation against three common aquifer testing problems: determination of (i) transmissivity and storage coefficient from non-leaky confined aquifer performance tests, (ii) transmissivity, storage coefficient, and vertical hydraulic conductivity of a confining unit from leaky confined aquifer performance tests, and (iii) transmissivity and storage coefficient from non-leaky confined aquifer performance tests with noisy data and boundary effects. The first two problems are well-addressed and the presented approach compares favorably to the results obtained from other published methods. The third problem, which the presented method can tackle more naturally than previously-published methods, underscores the flexibility of particle filtering and, in turn, the promise such methods offer for a myriad of other geoscience problems

Structural changes in the economy, such as new technological developments that create new conditions for the production and consumption of goods and services, have had a particularly strong impact on the popular music industry. This dissertation explores how musicians, record companies and publishers deal with the control dilemmas that the current environment poses for them. Music corporations face increasing financial pressures and struggle to find the right formulas for qualitative, yet commercial, music. Musicians try to create meaningful lives which involve writing and performing music. At the same time they try to make a decent living. Through an ethnographically inspired field study, the author finds that commercial sociability in the shape of phony friend-making practices emerges as an important control mechanism in music production, and an award-and-list culture operates as a classificatory control mechanism in music consumption. It is suggested that the popular music industry can be characterized by pseudo-Gemeinschaft. / Diss. Stockholm : Handelshögskolan, 2008

L'augmentation de l'intérêt concernant la part des réservoirs hydroélectrique dans l'augmentation de la concentration atmosphérique des Gaz à Effet de Serre (GES) a amené à mesurer les émissions nettes d'un réservoir hydroélectrique, Nam Theun 2 (NT2) dans la région subtropicale de la République Démocratique Populaire du Laos, Asie. Ce travail est la première évaluation de l'empreinte carbone des GES (c'est à dire : les émissions après ennoiement moins les émissions avant ennoiement) en relation avec la création d'un réservoir hydroélectrique. C'est le résultat d'une étude à grande échelle qui s'est déroulée pendant cinq ans (2008-2012). Nous avons tout d'abord quantifié les sources et les puits majeurs des GES des composants terrestres et aquatiques du paysage avant ennoiement (Mai 2008). Ensuite, à partir d'Avril 2009, cette étude similaire a été réalisée au niveau du réservoir, sa zone de marnage et son aval. C'est en Octobre 2009 que le réservoir hydroélectrique NT2 a, pour la première fois, atteint son niveau maximal et c'est huit mois plus tard, en Mars 2010, que les turbines ont fonctionnées pour la première fois. En se basant sur un suivi bimensuel et sur cinq missions de terrain couvrant toutes les saisons, les émissions des principaux GES (c'est à dire l'oxyde nitreux (N2O), le méthane (CH4) et le dioxyde de carbone (CO2)) ont été mesurées d'Avril 2009 à Décembre 2011. Les émissions ont été déterminées à la surface du réservoir (flux diffusifs et ébullitifs) ainsi que dans les sols de la zone de marnage, qui peut atteindre 370 km2 pour une surface totale de réservoir de 450 km2.

The Amphetamine Years is a history of psychostimulant drugs and their clinical applications in post-World War II American medicine. Comprising such well-known substances as the amphetamines (Benzedrine, Dexedrine), methylphenidate (Ritalin), and phenmetrazine (Preludin), this class of pharmaceuticals has been among the most widely consumed in the past half-century. Their therapeutic uses for a variety of indications such as depression, obesity, and attention-deficit/hyperactivity disorder (ADHD) in children, not to mention their relevance for a number of different medical specialties, reveals that psychostimulants have occupied an important, if underappreciated role in the practice of modern medicine. In this dissertation, I illuminate the various ways in which physicians, particularly psychiatrists, put these drugs to work in clinical practice. In short, I contend that physicians exploited the wide range of physiological and psychological effects of psychostimulants and made a place for them in different therapeutic settings, even ones characterized by competing views and theories about the workings of the human body and mind. My dissertation is distinguished by two prominent themes. First, I emphasize the clinician perspective as a vehicle for understanding the history of the psychostimulants, as well as related developments in psychiatry, pharmacotherapy, and the political economy of drugs, in the second half of the twentieth century. Scholars such Nicolas Rasmussen, David Courtwright, and Ilina Singh have elucidated the history of psychostimulants by emphasizing how pharmaceutical companies positioned their products in the medical marketplace. My dissertation takes a different, yet complimentary approach by studying clinicians, themselves, to further historical comprehension of the place of these pharmaceuticals within postwar medicine, society, and culture. Second, I advance the concept of "therapeutic versatility" to explain their historical trajectories. The complex set of psychological and physical effects these drugs produced made them ideal for a diverse range of therapeutic applications, which explains why they were embraced by many different medical specialties, why they were marketed by manufacturers for a variety of indications, and why they have enjoyed an enduring therapeutic lifespan, in spite of increasing efforts since the mid-1960s to regulate their availability and control their consumption. In addition to these two overarching themes, I advance five specific arguments in my dissertation. First, I contend that pharmaceutical markets were simultaneously created by the drug industry and clinicians. Pharmaceutical firms' efforts to develop markets for their products have been well documented by historians, but in my dissertation, I underscore the role also played by clinicians in discerning drugs' applications. Second, I argue that twentieth-century psychiatry's conception of illness and therapeutics may not be served best by strictly dividing its history along lines of institutional and outpatient treatment. Third, I demonstrate how the use of psychostimulants by analytically oriented psychiatrists during the 1950s complicates historical notions of paradigm shift from a psychodynamic to biological orientation. Psychotherapy and psychopharmacology were not competing paradigms; in practice, doctors often employed both. Fourth, I assert that an appreciation of psychiatrists' empirical and eclectic approaches to the use of drugs is necessary to comprehend the rise of psychiatric pharmacotherapy in the postwar era. Finally, I contend that in order to understand the relationship between medical applications of psychostimulants and their extramedical consumption, it is necessary to conceive of a plurality of distinct "amphetamine cultures," each characterized by a unique set of relationships between physician-prescribers, patient-consumers, pharmaceutical firms, and political authorities.

Angesichts der steigenden Anzahl von Funktionen in Fahrzeugen, insbesondere im Pkw, sind neue Bedien- und Anzeigesysteme notwendig, die eine optimale Bedienbarkeit der Funktionen sicherstellen und die Ablenkung des Fahrers von der Fahraufgabe minimieren. Im Rahmen dieser Arbeit wird dazu der Einsatz variabler Bedienelemente verfolgt, die sich der aktuellen Bedienaufgabe optimal anpassen. Ziel dieser Arbeit ist es insbesondere, Vorgehensweisen und Gestaltungsempfehlungen für variable Beschriftung von Tasten und zentrale Bedienelemente mit variabler Formcodierung für abgesetzte Bedien- und Anzeigesysteme zu erarbeiten. Unter Zuhilfenahme arbeitswissenschaftlicher Methoden wird dafür zunächst die Gestaltung variabler Beschriftung von Tasten untersucht und Empfehlungen für deren Gestaltung abgeleitet. Des Weiteren wird die Entwicklung eines zentralen Bedienelements mit variabler Formcodierung beschrieben. Dazu wird, aufbauend auf bekannten Entwicklungs- und Auswahlverfahren für Bedienelemente, eine Vorgehensweise zur Entwicklung variabler Bedienelemente vorgeschlagen. Das entwickelte variable zentrale Bedienelement wird darüber hinaus hinsichtlich seiner Bedienbarkeit und Ablenkungswirkung bewertet. Aus den Versuchsergebnissen konnten Gestaltungsempfehlungen abgeleitet werden, wie durch ein variables zentrales Bedienelement die Bedienbarkeit von abgesetzten Bedien- und Anzeigesystemen verbessert und die Ablenkungswirkung reduziert werden kann. Die Ergebnisse dieser Arbeit leisten einen Beitrag zur Entwicklung zukünftiger abgesetzter Bedien- und Anzeigesysteme und geben insbesondere Entwicklern und Gestaltern eine Hilfestellung beim Einsatz variabler Bedienelemente.

Information är idag en värdefull resurs i organisationer som blir mer och mer beroende av sina informationssystem. Information utsätts för olika hot och den behöver skyddas för att organisationer effektivt ska kunna driva sin verksamhet. Ett systematiskt informationssäkerhetsarbete hjälper organisationer att uppnå och upprätthålla en tillräcklig nivå av informationssäkerhet.   Studiens syfte är att undersöka hur informationssäkerhet hanteras inom organisationer i allmänhet i nuläget. En fallstudie har genomförts på Folktandvården, Region Jönköpings län för att undersöka hur Folktandvårdens medarbetare hanterar informationssäkerheten. Dessutom syftar studien till att utvärdera medvetenhet om informationssäkerhet hos medarbetarna på Folktandvården och att presentera förslag på hur hanteringen av personuppgifter kan förbättras i organisationer.  Blandade tekniker har använts för att samla information.  Litteraturstudier inom området informationssäkerhet har genomförts. Empirisk data har samlats in genom en enkätundersökning, intervjuer och skriftliga frågor som har skickats via e-post till utvalda ansvariga som jobbar specifikt med frågor som berör informationssäkerhet inom Folktandvården. Denna studie använder de svenska standarderna SS-ISO/IEC 27001:2014 och SS-ISO/IEC 27002:2014 för att utvärdera informationssäkerhet på Folktandvården, Region Jönköpings län samt att få en bild av hur informationssäkerhet hanteras inom organisationer. Organisationer kan upprätthålla säkerhet i sin informationshantering genom att tillämpa ett ledningssystem för informationssäkerhet (LIS) som bevarar konfidentialitet, riktighet (integritet) och tillgänglighet av information.  Informationssäkerhetsarbetet och införandet av LIS skiljer sig mellan organisationer eftersom de kan påverkas av organisationens behov och mål, storlek och struktur. Fallstudiens resultat visar att Folktandvården, Region Jönköpings län genomför en aktiv hantering av informationssäkerhet. Folktandvården klarar de flesta kraven som ställdes i standarderna. Däremot föreslås det i studien att fler utbildningsprogram ordnas för att öka medvetenheten kring informationssäkerhet. Dessa utbildningsprogram bör uppdateras regelbundet för att det fortsätter att vara i linje med organisatoriska policy och rutiner. Det rekommenderas även att organisationen utför informationsklassning fullt ut enligt den modellen som Folktandvården har. Dessutom rekommenderas att utveckla planeringen av kontinuitet för informationssäkerhet. Resultatet från enkätundersökningen visar att medarbetarna är medvetna om hur de hanterar informationssäkerhetsincidenter och upplever att systemen är tillgängliga för de behöriga. Flera av de förslag som presenterades av denna studie har hörsammats och kommer att leda till vidare arbete inom Folktandvården. Organisationers personuppgifter bör skyddas genom att tillämpa regler enligt gällande författningar. En ansvarig person i organisationen bör ge vägledning till de anställda om sitt ansvar för hantering av personuppgifter. / Information today is a valuable resource for organizations which become more and more dependent on their information systems. Information subject to various threats and the need to be protected in order that organizations can effectively run their business. A systematic information security helps organizations to achieve and maintain a sufficient level of information security. The study aims to investigate how information is managed within organizations in general. A case study has been performed in Folktandvården (the Public Dental Service), Region Jönköping County to investigate how the organization handle information security. In addition, the study aims to evaluate awareness of information security among employees at the business and to present proposals on how to improve handling of personal data. Mixed techniques have been used to gather information. Literature studies in the field of information security has been implemented. The empirical data collected through a questionnaire, interviews and written questions sent by e-mail to managers in Folktandvården. This study uses the standards SS-ISO / IEC 27001:2014 and SS-ISO / IEC 27002:2014 to evaluate the information in Folktandvården, Region Jönköping County and to get a picture of how information is managed within organizations. Organizations can maintain the security of their information by implementing an information security management system (ISMS) that preserves the confidentiality, integrity and availability of information. Information security and ISMS application differs between organizations, which could be affected by the organization's needs and goals, size and structure. Case study results show that Folktandvården, Region Jönköping County implements an active management of information. The organization manages most of the specifications in the standards. However this study proposes to organize more training programs for information security awareness. These programs should be updated regularly in order to continue to be in line with organizational policies and procedures. It is recommended that the organization performs information classification fully in accordance with the model it has. Additionally, it is recommended to develop the planning of continuity for information. The results from the questionnaire show that the employees are aware of how they handle information security incidents and they think that the systems are available for authorized access. Several of the proposals presented by this study have been heeded and will lead to further work in Folktandvården. Organizations' personal information should be protected by applying the rules in accordance with applicable regulations. A responsible person in the organization should provide guidance to employees about their responsibility for the handling of personal data.

- / In this thesis new advanced nonlinear control methods that solve the power system stabilization problem in a more efficient and integrated manner are considered. The proposed methods mainly concern with the primary level control of a power system that plays a central role in maintaining transient stability and obtaining a desired system performance. To this end, several new nonlinear control schemes mainly applicable on power system stabilizers (PSS) have been designed and extensively analyzed. For a theoretical assessment of the system operation the concepts of passivity and passivity margin are analyzed while the concept of Ω--passivity is introduced. Using partial feedback linearization and backstepping design techniques on suitable models of the system under consideration (power system) the Ω--passivity property of the system is proved. This property is further improved through the control in the closed-loop design. To this end, several control schemes are developed and a series of different theoretical problems have been solved on using simple output feedback and advanced nonlinear control methods like sliding mode control, adaptive control or a combination of them. A significant breakthrough has been achieved with the use of fuzzy techniques in these schemes yielding designs with combined advantages of both fuzzy and adaptive control methods. A detailed stability analysis, based on Lyapunov functions, has been used to prove that the proposed controllers guarantee either uniform ultimate boundedness or asymptotic stability for the closed-loop system. The proposed schemes are examined assuming that the system operates under parameter uncertainties as well as external disturbances. The theoretical analysis indicates that regulating some design parameters of the proposed controllers one can significantly improve the robustness and the disturbance attenuation capability of the system. Extensive simulations on a two machines infinite bus test system have been carried out to evaluate the effectiveness of the proposed schemes as these are applied on the PSS of each machine. Hard cases of three phase faults or significant power demand changes have been simulated. The simulation results show that the proposed nonlinear controllers enhance the damping of the electromechanical oscillations with respect to classical AVR/PSS and improve their robustness to parameter uncertainties and disturbance attenuation capability. Using similar techniques, speed governor controls (SGC) are also designed. An adaptive control scheme is proposed that ensures asymptotic stabilization of the closed-loop system as proved by standard Lyapunov techniques. Simulations are carried out for the one generator system connected to infinite bus. The simulation results confirm a significant improvement in the electromechanical oscillations damping compared to conventional speed governor controls. An important contribution of the thesis involves the coordination and management of the controls at the primary level. The design is carried out so that each control is not competing with the action of the other and it is cooperating to complement the action of the other. In this frame, first, the coordinated operation of the designed nonlinear power system stabilizers with the classical AVR/PSS is proposed. Particularly, the sequential operation of these controllers is considered in the following way: immediately after a fault, only the nonlinear controller operates but when the fault attenuates the classical AVR/PSS takes over. In this way, significant transient enhancement and voltage regulation after the large transients can be achieved. To implement this kind of operation a soft-switching logic from the one controller to the other is proposed by using a fuzzy logic mechanism to determine which controller will act each time period. In this way, it is avoided a discontinuous switching that can create a number of problems and may even lead to instabilities. The analysis and the simulation results confirm the validity of this approach since it is shown that the coordinated control scheme has an almost identical transient performance with the nonlinear controllers ensuring simultaneously the voltage regulation at the desired set-point. The same approach is used for the coordinated operation of FACTS with the excitation controllers. To this end, a static var compensator (SVC) controller is developed which, during a fault, acts to improve the transient stability. During the transient period, the SVC uses as inputs not the voltage at the connecting point but suitable signals from neighbor stations in order to contribute to the electromechanical oscillations damping; in the sequel, it returns to its normal operation maintaining the voltage level at the connecting point at a specified value. A soft switching scheme is also applied while signal transmission delays are taken into the account. The simulation results of a three phase short-circuit in a system with a single machine connected to infinite bus through a bus that has a SVC attached, indicate that this coordinated control scheme improves the transient stability even more (in comparison to the previous coordinated scheme). Finally, coordinated control logic is used for the design of both the speed governor control and the PSS. This is needed when the operation of the PSS cannot be considered completely independent and decoupled from the speed governor dynamics (in the case of fast valve operation). In this combined system a parallel design of both the SGC and the PSS ensures the uniform ultimate boundedness of the complete closed-loop system. Moreover, the use of continuous switching through fuzzy logic, as mentioned before, between these controllers and the classical AVR/PSS (for the excitation system) and a PID control (for the SGC) is proposed. The simulation results on the two machines infinite bus system clearly confirm the superiority of the coordinated control scheme with respect to the classical AVR/PSS excitation controllers and PID speed governor controllers. As a conclusion, new combined advanced nonlinear control schemes are analyzed and proposed for power systems. From the stability analysis and the simulation results it is clearly confirmed that the application of these nonlinear controls can be effectively improve the transient behavior as well as the robustness and disturbance attenuation of a power system. It is also proved that, without extreme cost, coordinated control schemes implemented through the proposed soft-switching techniques further enhance the transient and dynamic performance of the system.

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal

This thesis explores home energy management (HEM), an emerging field for interface design and sustainability. Section 1 introduces HEM’s broader context. In Section 2, I review the literature surrounding HEM. Section 3 outlines the usability study on the ecobee Smart Thermostat, to evaluate the technology’s ease-of-use, and better understand users’ experience with current HEM technology. Section 4 describes a “Critical Making” workshop, where participants investigated HEM through material interaction and discussion. Section 5 describes and evaluates the potential design spaces gleaned from previous sections. In Section 6, I return to the literature to investigate key concepts underlying the design intervention for the chosen design space. Section 7 describes my design intervention and experimental evaluation. In Section 8, I present the study results, which suggest enhanced display labelling had a significant and directional effect on user-selected temperatures. In Section 9, I discuss these results, study limitations, and make conclusions and recommendations.