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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.
781

The Design of Home Energy-management Interfaces: Effects of Display Type on Thermostat Temperature Selection

Stein, Joshua 28 November 2013 (has links)
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.
782

Engineering-orientierte Steuerungsarchitektur auf der Basis von Aktionsprimitiven für Anwendungen in der Robotik / Engineering-oriented Control Architecture based on Action Primitives for Applications in Robotics

Hennig, Matthias 16 November 2012 (has links) (PDF)
In der vorliegenden Arbeit wird die flexible Steuerungsarchitektur Apeca für Systeme der Robotik sowie der robotergestützten Fertigungstechnik vorgestellt. Dafür werden verschiedene Anforderungen identifiziert und innerhalb eines Entwurfs vereint. Ein Hauptaugenmerk des dabei entstandenen Konzeptes ist es, einen vereinfachten Engineeringprozess für den Steuerungsentwurf zu ermöglichen. Dieser Ansatz wird durch die Verwendung von Aktionsprimitiven ermöglicht, die in Form atomarer Systemverhalten in einer speziellen Modulhierarchie eingesetzt werden. Hierzu erfolgt innerhalb der Steuerungsarchitektur eine Trennung zwischen einem funktionsorientierten verhaltensbasierten Modell zur hierarchischen sowie funktionell parallelen Ausführung von Aktionsprimitiven und einem ablauforientierten Modell zur aufgabenabhängigen Aktivierung derselben. Mit Hilfe eines Nutzerkonzepts werden diese Modelle verschiedenen Anwendern zugeordnet. Die objektorientierte Realisierung dieses Entwurfs ermöglicht die Verwendung und Synchronisation von mehreren Teilsystemen innerhalb einer Steuerung. In der Arbeit wird sowohl der entstandene Entwurf diskutiert als auch eine prototypische Implementierung vorgestellt. Abschließend werden die Ergebnisse anhand verschiedener Demonstrationsszenarien präsentiert. / In this present work, the Apeca framework, a flexible control architecture for robotic systems, is introduced. The conceptual design combines different requirements identified in miscellaneous robotic control approaches. The main focus of the resulting concept is on a simplified engineering process for the controller design. This approach is supported by the use of atomic system behaviors, the so called action primitives, in a special module hierarchy. For this purpose a distinction between a functional behavior based system model with hierarchically and also parallelly executed action primitives and a sequential control system model with a task-dependent activation of the primitives is proposed. These models are assigned to different users through a distinct user concept. An object-oriented implementation of the proposed architecture allows the utilization and synchronisation of multiple (sub-)systems within one framework. In this work the proposed framework will be discussed, a prototypical implementation will be presented and results based on different experimental scenarios will be shown.
783

Optogenetic feedback control of neural activity

Newman, Jonathan P. 12 January 2015 (has links)
Optogenetics is a set of technologies that enable optically triggered gain or loss of function in genetically specified populations of cells. Optogenetic methods have revolutionized experimental neuroscience by allowing precise excitation or inhibition of firing in specified neuronal populations embedded within complex, heterogeneous tissue. Although optogenetic tools have greatly improved our ability manipulate neural activity, they do not offer control of neural firing in the face of ongoing changes in network activity, plasticity, or sensory input. In this thesis, I develop a feedback control technology that automatically adjusts optical stimulation in real-time to precisely control network activity levels. I describe hardware and software tools, modes of optogenetic stimulation, and control algorithms required to achieve robust neural control over timescales ranging from seconds to days. I then demonstrate the scientific utility of these technologies in several experimental contexts. First, I investigate the role of connectivity in shaping the network encoding process using continuously-varying optical stimulation. I show that synaptic connectivity linearizes the neuronal response, verifying previous theoretical predictions. Next, I use long-term optogenetic feedback control to show that reductions in excitatory neurotransmission directly trigger homeostatic increases in synaptic strength. This result opposes a large body of literature on the subject and has significant implications for memory formation and maintenance. The technology presented in this thesis greatly enhances the precision with which optical stimulation can control neural activity, and allows causally related variables within neural circuits to be studied independently.
784

Understanding Spatio-Temporal Variability and Associated Physical Controls of Near-Surface Soil Moisture in Different Hydro-Climates

Joshi, Champa 03 October 2013 (has links)
Near-surface soil moisture is a key state variable of the hydrologic cycle and plays a significant role in the global water and energy balance by affecting several hydrological, ecological, meteorological, geomorphologic, and other natural processes in the land-atmosphere continuum. Presence of soil moisture in the root zone is vital for the crop and plant life cycle. Soil moisture distribution is highly non-linear across time and space. Various geophysical factors (e.g., soil properties, topography, vegetation, and weather/climate) and their interactions control the spatio-temporal evolution of soil moisture at various scales. Understanding these interactions is crucial for the characterization of soil moisture dynamics occurring in the vadose zone. This dissertation focuses on understanding the spatio-temporal variability of near-surface soil moisture and the associated physical control(s) across varying measurement support (point-scale and passive microwave airborne/satellite remote sensing footprint-scale), spatial extents (field-, watershed-, and regional-scale), and changing hydro-climates. Various analysis techniques (e.g., time stability, geostatistics, Empirical Orthogonal Function, and Singular Value Decomposition) have been employed to characterize near-surface soil moisture variability and the role of contributing physical control(s) across space and time. Findings of this study can be helpful in several hydrological research/applications, such as, validation/calibration and downscaling of remote sensing data products, planning and designing effective soil moisture monitoring networks and field campaigns, improving performance of soil moisture retrieval algorithm, flood/drought prediction, climate forecast modeling, and agricultural management practices.
785

EU: Kompetenzabgrenzung zwischen Gemeinschafts- und Unionspolitiken : dargestellt am Beispiel der Ausfuhrkontrolle von Gütern mit doppeltem Verwendungszweck (Dual-use-Gütern) /

Moestl, Michaela. January 2004 (has links)
Thesis (doctoral)--Universität, Wien, 2002. / Academy publication.
786

Trust and risk in the context of securities lending : a sociological analysis

Bruce, Johannes Conradie 31 January 2005 (has links)
This dissertation uses a Sociological approach to analyse the risks associated with the practice of securities lending. Risks are those factors that inhibit the development of trust, and trust is essential for people to participate in financial transactions like securities lending. In this dissertation we show that, although there are a number of risks, individual and systemic, that are associated with securities lending, practitioners have, over time, developed an array of risk management procedures and practices to keep these risks at acceptable levels. Securities lending is however not practiced in a vacuum and the relevance of these risk management procedures is largely determined by the cultural environment in which it is practised. Values, norms and sanctions are crucial as social controls over behaviour that transpires in social structures. The presence of structural conditions necessary for the development of a culture of extreme opportunism is shown as arguably the greatest source of risk facing those who participate in financial transactions like securities lending. / Sociology / M.A.
787

Crise brasileira de 2014: causas locais ou resposta ao cenário internacional?

Cytrynowicz, Eduardo 18 August 2017 (has links)
Submitted by Eduardo Cytrynowicz (educytry@gmail.com) on 2017-08-28T17:10:31Z No. of bitstreams: 1 diss_mestrado-ecytrynowicz-vfinal.pdf: 806898 bytes, checksum: 3d3b1685fc0da356141308510cfa7cf6 (MD5) / Rejected by Joana Martorini (joana.martorini@fgv.br), reason: Prezado Eduardo, boa tarde. O arquivo foi rejeitado por não estar de acordo com as Normas. Segue abaixo o link com todos os requisitos necessários para aprovação do seu trabalho. http://sistema.bibliotecas-sp.fgv.br/sites/bibliotecas.fgv.br/files/bibnormas1.pdf Qualquer dúvida, entre em contato no e-mail: mestradoprofissional@fgv.br ou ligue: 3799-7764 Att. on 2017-08-28T18:05:10Z (GMT) / Submitted by Eduardo Cytrynowicz (educytry@gmail.com) on 2017-08-28T18:24:43Z No. of bitstreams: 1 diss_mestrado-ecytrynowicz-vfinal.pdf: 806514 bytes, checksum: c54ae67e5045ab12bc44ed55deacd0ed (MD5) / Rejected by Joana Martorini (joana.martorini@fgv.br), reason: . on 2017-08-28T18:46:48Z (GMT) / Submitted by Eduardo Cytrynowicz (educytry@gmail.com) on 2017-08-28T18:55:45Z No. of bitstreams: 1 diss_mestrado-ecytrynowicz-vfinal.pdf: 806482 bytes, checksum: b340baf6ad3e6a4483e58bb92c55448e (MD5) / Approved for entry into archive by Joana Martorini (joana.martorini@fgv.br) on 2017-08-28T19:04:22Z (GMT) No. of bitstreams: 1 diss_mestrado-ecytrynowicz-vfinal.pdf: 806482 bytes, checksum: b340baf6ad3e6a4483e58bb92c55448e (MD5) / Made available in DSpace on 2017-08-29T12:42:34Z (GMT). No. of bitstreams: 1 diss_mestrado-ecytrynowicz-vfinal.pdf: 806482 bytes, checksum: b340baf6ad3e6a4483e58bb92c55448e (MD5) Previous issue date: 2017-08-18 / Empregamos o método de controle sintético para realizar um estudo de caso visando avaliar se o encolhimento econômico do Brasil durante o governo da presidente Dilma Rousseff foi causado por fatores domésticos ou internacionais. O estudo comparou os resultados da economia brasileira ao longo de toda duração desse governo em comparação com o potencial crescimento para o país. Estimamos esse contrafactual através de dados de países não afetados pelas políticas locais. Os resultados empíricos sugerem que, caso a economia brasileira tivesse seguido as mesmas tendências dos demais países, provavelmente teria experimentado um crescimento sustentável, muito diferente do que realmente ocorreu. / We use the synthetic control method to perform a case study to understand if the economic shrinking of Brazil during the government of President Dilma Rousseff was caused by domestic or international factors. The study compared the outcomes of the Brazilian economy under the entire government as opposed to what would have been the potential outcomes defined through a counterfactual estimated through foreign countries, thus unaffected by the local policies. The empirical results suggest that was Brazil to follow the same trends that the rest of the countries experienced, it would probably have experienced a sustainable growth, much different from what has actually happened.
788

Assessment of corporate governance reporting in the annual reports of South African listed companies

Moloi, Steven Tankiso Mthokozisi 30 November 2008 (has links)
This dissertation reflects the results of a study during which the 2006 annual reports of the top-40 JSE listed companies, were assessed for their disclosure of the required corporate governance statements. Content analysis was used to identify the information. The results obtained indicate that the majority of the JSE's top-40 listed companies adhere to good corporate governance disclosure practices. However, there are areas in which the non-disclosure of information was prevalent. These include the disclosure of information on the selection of external auditors and whistle blowing. Future research, employing sources such as SENS announcements, press releases, trading updates, cautionary announcements and websites together with annual reports should be conducted. / Financial Accounting / M.Com. (Accounting)
789

Juridical constraints on monetary sovereignty : implications for international economic law

Ndlovu, Philani Lithandane 04 1900 (has links)
Money is a public good. The regulation of its creation, supply and distribution is of national and international interest. Monetary stability is an important regulatory goal conducted through an interaction of economic, political, religious factors as well as legislative action. The state plays an intermediary role, bridging domestic interests and international interests. Increasing interdependence between national economic systems and international obligations sometimes leads to the manipulation of systems as well as currency wars. Regulation is done through co-operative international action since domestic regulators are no longer sufficiently equipped to do so. Resultantly, there is an emergence of new structural paradigms to deal with it. Meanwhile, states still enjoy certain residual competences of sovereignty. Numerous legal factors act as constraints on sovereignty with far reaching implications on states’ regulatory space. In light of the divergence of regulatory objectives, there is an apparent need to balance municipal with international interests on the regulation of the monetary system. / Mercantile Law / LL. M.
790

Desenvolvimento de bancada didatico-experimental de baixo custo para aplicações em controle ativo de vibrações / Design of a didactic ande experimental testbed of low cost for applications in active control of vibration

Amorim, Mauricio Jose 21 February 2006 (has links)
Orientador: Euripedes Guilherme de Oliveira Nobrega / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-06T09:41:01Z (GMT). No. of bitstreams: 1 Amorim_MauricioJose_M.pdf: 2137966 bytes, checksum: bc8b0e13365a14be8d6bd6c336785b31 (MD5) Previous issue date: 2006 / Resumo: Este trabalho apresenta uma bancada didática destinada ao ensino nos cursos de engenharia de aplicações em projetos de controle, processamento digital de sinais e programação em tempo real. Bancadas didáticas são ferramentas indispensáveis ao ensino, considerando que os conceitos vistos apenas em sala de aula são muitas vezes abstratos. A bancada em questão foi desenvolvida partindo de projeto mecânico já existente, tendo sido colocados na estrutura sensores extensométricos para obter a resposta do sistema como deformação e projetado o circuito condicionador do sinal para essa resposta. Para a prirneira fase, envolvendo identificação, controle da estrutura e análise dos resultados, foram projetados dois acionadores para os motores que aplicam o distúrbio e o esforço de controle sobre a planta. Após terem sido satisfeitas as etapas da primeira fase, o próximo passo foi transferir o sistema de controle para uma configuração embarcada utilizando um microcontrolador. Para tanto, algumas adaptações e novos projetos emergiram diante da mudança do ambiente de processamento. A necessidade de adaptar os sinais para a nova placa de aquisição exigiu mudança em alguns circuitos. o acionador de motor para uma saída de controle modulada em largura de pulso foi desenvolvido utilizando componentes discretos. Além disso, é detalhadamente abordada a programação em tempo real do sistema de controle em questão / Abstract: This work presents the design of a didactic tesbed intended to teaching control system design, digital processing of signals and real-time programming. Didactic tesbeds are very vaIuabIe tools when applying concepts developed inside the classroom. The testbed developed here is built upon a previous mechanical design. Strain gages were used as measuring devices using a conditioning circuit. FirstIy, system identification, structural control and analysis of the results were proceeded, two motor drives were designed to operate motors performing both disturbance and control inputs. Afterwards, the control system was redesigned to operate using a micracontraller unit in a embedded architeture. Some adaptations on the circuits were needed and are covered here. A DC motor circuit driver using PWM signal was developed using discrete components. Besides, real-time programming of the control system is covered in detail / Mestrado / Mecanica dos Sólidos e Projeto Mecanico / Mestre em Engenharia Mecânica

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