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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.
241

Context aware voice user interface

Demeter, Nora January 2014 (has links)
In this thesis I address the topic of a non-visual approach for interaction on mobile,as an alternative to their existing visual displays in situations where hands free usageof the device is preferred. The current technology will be examined through existingwork with special attention to its limitations, which user groups are currently using anysort of speech recognition or voice command functions and look at in which scenariosare these the most used and most desired. Then I will examine through interviews whypeople trust or distrust voice interactions and how they feel about the possibilities andlimitations of the technology at hand, how individual users use this currently and wheredo they see the technology in the future. After this I will develop an alternative voiceinteraction concept, and validate it through a set of workshops.
242

A model for HIV and AIDS care, research and policy interface / Mantoa Augustina Mofokeng

Mofokeng, Mantoa Augustina January 2014 (has links)
Study background Nursing plays a pivotal role in the care of people living with HIV and AIDS and makes an obvious contribution in influencing HIV and AIDS policy. Studies suggest that despite their knowledge and experience nurses do not systematically inform policy. Against the background of the research problem above, the following research question was posed: How can a model for HIV and AIDS care, research and policy interface be developed? Purpose of the study and objectives The purpose of this study was to develop and describe a model for HIV and AIDS care, research and policy interface. The study objectives were developed in two phases relevant to the methodology of developing a model. Phase One objectives Phase 1 objectives – The identification and classification of concepts in relation to HIV and AIDS care, research and policy interface.  To examine how HIV and AIDS stigma influences nurses‟ provision of prevention, care and treatment to patients and families.  To explore and describe how HIV and AIDS affects the workforce.  To examine the HIV and AIDS policies and interventions Phase 2 objectives Phase 2 objectives – Concept definition, description and model development  To describe a conceptual framework  To construct the relational statements amongst the identified concepts Methods Three different instruments were used in both qualitative and quantitative collection of data. These were the Human Resource Management (HRM) Rapid Assessment Tool, the Clinical Survey and the Interview Guide. Content and construct validity were used to determine rigour of the quantitative instruments; trustworthiness of the qualitative data was established according to Lincoln and Guba (1985) and Krefting‟s (1991) considerations of trustworthiness Results Concluding statements were deduced from the analysed data. These were further deducted into: HIV and AIDS care, research, HIV and AIDS stigma, staff outcomes and policy. These core concepts were used to develop a model for HIV and AIDS care, research and policy interface. Recommendations Recommendations for practice, research, education and policy included stakeholder inclusion in HIV and AIDS policy, increasing the research component of clinical nurses and rolling out the use of HIV and AIDS care, research and policy interface model. / PhD (Nursing), North-West University, Potchefstroom Campus, 2015
243

A model for HIV and AIDS care, research and policy interface / Mantoa Augustina Mofokeng

Mofokeng, Mantoa Augustina January 2014 (has links)
Study background Nursing plays a pivotal role in the care of people living with HIV and AIDS and makes an obvious contribution in influencing HIV and AIDS policy. Studies suggest that despite their knowledge and experience nurses do not systematically inform policy. Against the background of the research problem above, the following research question was posed: How can a model for HIV and AIDS care, research and policy interface be developed? Purpose of the study and objectives The purpose of this study was to develop and describe a model for HIV and AIDS care, research and policy interface. The study objectives were developed in two phases relevant to the methodology of developing a model. Phase One objectives Phase 1 objectives – The identification and classification of concepts in relation to HIV and AIDS care, research and policy interface.  To examine how HIV and AIDS stigma influences nurses‟ provision of prevention, care and treatment to patients and families.  To explore and describe how HIV and AIDS affects the workforce.  To examine the HIV and AIDS policies and interventions Phase 2 objectives Phase 2 objectives – Concept definition, description and model development  To describe a conceptual framework  To construct the relational statements amongst the identified concepts Methods Three different instruments were used in both qualitative and quantitative collection of data. These were the Human Resource Management (HRM) Rapid Assessment Tool, the Clinical Survey and the Interview Guide. Content and construct validity were used to determine rigour of the quantitative instruments; trustworthiness of the qualitative data was established according to Lincoln and Guba (1985) and Krefting‟s (1991) considerations of trustworthiness Results Concluding statements were deduced from the analysed data. These were further deducted into: HIV and AIDS care, research, HIV and AIDS stigma, staff outcomes and policy. These core concepts were used to develop a model for HIV and AIDS care, research and policy interface. Recommendations Recommendations for practice, research, education and policy included stakeholder inclusion in HIV and AIDS policy, increasing the research component of clinical nurses and rolling out the use of HIV and AIDS care, research and policy interface model. / PhD (Nursing), North-West University, Potchefstroom Campus, 2015
244

Telemetry System for the Solar Miner VII

Guenther, Clinton, Mertens, Robert, Lewis, Adam 10 1900 (has links)
ITC/USA 2010 Conference Proceedings / The Forty-Sixth Annual International Telemetering Conference and Technical Exhibition / October 25-28, 2010 / Town and Country Resort & Convention Center, San Diego, California / This paper describes a telemetry system used in the Missouri S&T solar car, which competed in the American Solar Challenge. The system monitors parameters of a number of the on-board electronic and mechanical systems, and also the activities of the vehicle driver. This data is transmitted to a lead vehicle, where the support team analyzes the performance in real-time to optimize the vehicle's performance. In previous vehicles the data was displayed using a LabVIEW based user interface. In this work we will describe a custom software solution, which provides the team with additional flexibility to display and analyze the data.
245

Effet du nanorenforcement sur les propriétés physico-mécaniques et la durabilité des PRF utilisés en génie civil

Gauvin, Florent January 2016 (has links)
Depuis des années, les polymères renforcés de fibres (PRF) sont de plus en plus utilisés, notamment dans le domaine du génie civil. Ces matériaux composites sont rigides, tenaces, légers et ils sont inertes face à la corrosion électrochimique, ce qui en fait d’excellents candidats pour de nombreuses applications, par exemple comme barres d’armature dans le béton ou en réhabilitation externe des structures. Récemment, la communauté scientifique s’est tournée vers l’utilisation des nanocomposites polymère (PNC), matériaux biphasés constitués d’une matrice polymère mélangée à des nanoparticules. La très grande surface spécifique de ces dernières augmente significativement les propriétés mécaniques, thermiques ou barrières des polymères. Ces PNC sont de bons candidats pour la réhabilitation et le renforcement des structures en béton. Cependant, les matériaux à matrice polymère soulèvent diverses questions, comme leur dégradation face à l’environnement d’application, humide et parfois alcalin, ou leur mauvaise interface fibre/matrice causée par les natures différentes des fibres hydrophiles et des matrices polymères hydrophobes. Pour répondre à ces problématiques, cette étude porte sur le nanorenforcement des PRF à matrice polymère thermodurcissable utilisés en génie civil. Des nanoparticules, dispersées dans les matrices polymères sous forme de feuillets, induisent un phénomène de tortuosité limitant la diffusion au sein du matériau, augmentant ainsi la durabilité. Ces feuillets peuvent être des argiles, comme les silicates, ou des graphites exfoliés, comme le graphène. Pour améliorer l’interface fibre/résine des PRF, des traitements de surface sur des fibres minérales et naturelles sont effectués pour améliorer leur affinité avec des matrices thermodurcissables. Les objectifs principaux du nanorenforcement sont de : (1) augmenter les propriétés barrières des vinylesters pour augmenter leur durabilité et (2) améliorer l’interface dans les PRF à matrice thermodurcissable. Les résultats montrent que l’intercalation de nanoargiles dans les vinylesters augmente sensiblement la durabilité du polymère, en limitant la diffusion d’humidité au sein du matériau, tout en stoppant l’hydrolyse de la matrice. L’addition de faibles fractions (0.5 % en poids) de graphène oxydé augmente ainsi de plus de 15% les propriétés en flexion du polymère, tout en diminuant l’absorption à saturation (- 8%). À l’interface fibre/matrice, le nanorenforcement réalisé avec de la fumée de silice ou des nanocristaux d’amidon augmente non seulement les propriétés en traction des fibres de basalte et de bambou (jusqu’à 20%), mais aussi leurs interfaces avec les matrices thermodurcissables (vinylester et bio-époxy), avec une augmentation de plus de 25% des propriétés mécaniques des PRF réalisés avec ces fibres modifiées.
246

Hemp nanocellulose : fabrication, characterisation and application

Dasong, Dai January 2015 (has links)
Nanocellulose has gained lots of attentions in recent years due to the development of nanotechnology. Thousands of publications have been reported about the fabrication, characterization and application of nanocellulose, among which most of the nanocelluloses were fabricated from the microcrystalline cellulose (MCC) or pulp, and only two methods about the nanocellulose fabrication have been reported, i.e. sulphuric acid hydrolysis and mechanical treatment. The sulphuric acid method can only obtain low yield of nanocellulose and the mechanical treatment can not fabricate nanocellulose with high crystallinity index (CI) and well separation. These problems limit the scale up of nanocellulose to industrial area. Moreover, none of works has reported the application of nanocellulose for the modification of natural fibres and only a few works reported the reinforcement of epoxy with nanocellulose. In this this research, we fabricated nanocellulose directly from hemp fibres by employing oxidation/sonication method with the aim to solve the main problems of nanocellulose fabrication with sulphuric acid hydrolysis or mechanical. By using this method the yield of nanocellulose could up to 54.11 % and the crystallinity of nanocellulose was 86.59 %. In order to expand the application of nanocellulose, we investigated the modification of natural fibres (hemp) with nanocellulose and the fabrication of nanocomposite. Two-step modification, i.e. dodecyltrimethylammonium bromide (DTAB) pretreatment and nanocellulose modification, was used to modify hemp fibres. In this process, we systematically investigated the deformation of hemp fibres, revealed the mechanism of deformation on the mechanical property of single fibre by using Fourier transform infrared spectroscopy (FTIR) and investigated the effect of deformation on the hemp fibre modification with nanocellulose by using energy dispersive X-ray (EDX). The two-step modification increased the mechanical properties of hemp fibres significantly. Compared with raw hemp fibres, the modulus, tensile stress and tensile strain of the two-step nanocellulose modified hemp fibres increase by 36.13 %, 72.80 % and 67.89 %, respectively. Moreover, two-step modification facilitated the improvement of interfacial property of fibres. This novel natural fibre modification provides new clue to exploit nanocellulose as a green chemical agent for natural fibres modification. We modified nanocellulose by using curing agent of epoxy---diethylenetriamine (DETA). This modification could increase the dispersity of nanocellulose in epoxy and reinforce epoxy. Compared with epoxy, the modulus, tensile stress and tensile strain of the modified nanocellulose/epoxy nanocomposite increased 1.42 %, 15.44 % and 27.47 %, respectively.
247

Use of ATR spectroscopy to probe hetergeneously catalysed selective hydrogenations

Morgan, Richard William January 2015 (has links)
No description available.
248

A SIMPLE DECOMMUTATION SCHEME FOR THE TELEMETRY TEST STATION

Martin, Kamalini, Vanitha, M., Manjunath, P.C. 11 1900 (has links)
International Telemetering Conference Proceedings / November 04-07, 1991 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The Telemetry Test Station has been developed at the Digital Systems Division, ISRO Satellite Centre, to test the housekeeping telemetry packages which will be flown onboard satellites. The heart of the test procedure is the decommutation, display and processing of the telemetry output format. The decommutation has been achieved by designing a simple plug in card to an IBM PC/XT compatible computer and writing the related assembly language software. The card and the software have been extensively tested and found to work satisfactorily upto 60 Kbps PCM data rate. To make the hardware and software flexible and truly general purpose, the acquisition should be independent of the modes of operation and data formats. All the parameters which define acquisition display and processing are therefore programmable and can be changed at any time. The parameters which influence acquisition are bit rate, word rate, frame rate, length of word, length of frame and frame synchronous code. The bit rate is transparent, i.e., need not be set by the user. The word length is assumed to be 8 bits or multiples of 8 bits. The other parameters are programmable at any time during the test session. Similarly, the parameters which affect display are the display rate, and positioning of the format including highlighting, alarm signals, related information etc. This gives a user the facility to tailor the display to his liking. The storage is also flexible and independent of display. All these modes are in real time and have therefore been coded in assembly. It has been found that a large part of the software is needed for user interface alone and user requirement is far more changeable than expected. The software is therefore designed for change. The problems and solutions in achieving these features are discussed in this paper.
249

ASPECTS OF OPERATOR INTERFACE DESIGN FOR AN AUTOMATIC TRACKING ANTENNA CONTROLLER

DeBrunner, Keith E. 10 1900 (has links)
International Telemetering Conference Proceedings / October 22-25, 1984 / Riviera Hotel, Las Vegas, Nevada / The processing power afforded by embedded microcomputers in state-of-the-art control applications offers the design engineer greatly expanded opportunities for improved ergonomic design, even without the use of “soft” actuator and/or display devices (which are sometimes undesirable and/or unacceptable). Especially important is the exploitation of software to simplify the hardware design while simultaneously implementing decision/mode logic that would be prohibitively expensive if done in hardware alone. The designer is often confronted with an ocean of possibilisties, and must make intelligent decisions in order to satisfy increasingly demanding applications and sophisticated users. The design decisions and resulting features and behaviors of an automatic antenna control unit are discussed from the operators point of view (black box), but also with the intention to detail some of the logic necessary to implement these features. This is prefaced by a discussion of the characteristics of the primary operator interface, the front panel, and the factors that influenced its design. Areas for future improvement of the design are also mentioned.
250

Thermal contact resistance in carbon nanotube forest interfaces

Taphouse, John Harold 27 May 2016 (has links)
The continued miniaturization and proliferation of electronics is met with significant thermal management challenges. Decreased size, increased power densities, and diverse operating environments challenge the limitations of conventional thermal management schemes and materials. To enable the continuation of these trends thermal interface materials (TIMs) that are used to enhance heat conduction and provide stress relief between adjacent layers in a electronic package must be improved. Forests comprised of nominally vertically aligned carbon nanotubes (CNTs), having outstanding thermal and mechanical properties, are excellent candidates for next-generation thermal interface materials (TIMs). However, despite nearly a decade of research, TIMs based on vertically aligned CNT forests have yet to harness effectively the high thermal conductivity of individual CNTs. One of the key obstacles that has limited the performance of CNT TIMs is the presence of high thermal contact resistances between the CNT free ends and the surfaces comprising the interface. The aim of this research is to better understand the mechanisms by which the thermal contact resistance of CNT forest thermal interfaces can be reduced and to use this understanding towards the design of effective and to scalable processing methods. Contact area and weak bonding between the CNT tips and opposing surface are identified as factors that contribute significantly to the thermal contact resistance. Three strategies are explored that utilize these mechanisms as instruments for reducing the contact resistance; i) liquid softening, ii) bonding with surface modifiers, and iii) bonding with nanoscale polymer coatings. All three strategies are found to reduce the thermal contact resistance at the CNT forest tips to below 1 mm2-K/W, a value to where it is no longer the factor limiting heat conduction in CNT forest TIMs. These strategies are also relatively low-cost and amenable to scaling for production when compared to existing metal-based bonding strategies.

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