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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.
131

To make a mole hill out of a mountain : challenges in designing a recognizable GUI for an e-newspaper service on small screen devices

de Steur, Giel January 2006 (has links)
<p>The purpose of this study was to: obtain and review guidelines for designing on a small screen </p><p>from several theoretic sources and to purpose own guidelines for this context. There was </p><p>chosen for the development of 3 different prototypes meant for the use on 3 different mobile </p><p>devices. Those mobile devices had a different screen size and were: an e-reader, PDA and </p><p>mobile phone. The prototypes provided the user with a future e-newspaper service (a TV </p><p>schedule). </p><p> </p><p>First design principles for good usability on small screens were abstracted from literature. </p><p>With this knowledge the three prototypes were developed. The development started with </p><p>writing down the functional and user requirements for the prototypes. After that the </p><p>developing process had two stages. The first stage was a low-fidelity prototype, this were </p><p>sketches of the graphical user interface that was commented by users. The second stage was </p><p>a high-fidelity prototype, this stage consisted of three fully functional prototypes. The three </p><p>different prototypes were used in a user evaluation. After the evaluation interviews with the </p><p>users took place to obtain additional information. </p><p> </p><p>In this research the main question was: “What are the challenges for designing the </p><p>(graphical) user interface, as a part of an e-newspaper service which is aimed at use on </p><p>multiple devices with heterogeneous screen sizes, to be recognized as the same service?”. </p><p> </p><p>The results from this research are three challenges in designing the (graphical) user interface </p><p>for devices with small screens. These challenges are: how to make the user recognize the </p><p>service in the software (recognition of service), how to develop one service on multiple </p><p>devices (use on multiple devices) and how to develop software that it is useful and pleasant </p><p>to use (usable software). In total fifteen guidelines derived from theory were found, this </p><p>research shows that thirteen of them are applicable when designing for small screens. Three </p><p>of those thirteen are reformulated in this study to make them fit better in the context. Next to </p><p>this, seven additional guidelines were proposed in this study. Examples of the purposed </p><p>guidelines are: reconstruct the layout from the non-digital service in the interface as much as </p><p>possible, explore the targeted user group, built further on their mental model and pay </p><p>attention to possible disabilities of the group, implement extra’s that give users a good reason </p><p>to use the service and make it easy for the user to select the sought information.</p>
132

Contextual design for touch screen devices

Kozuch, Kamil January 2010 (has links)
<p>Designing touch screen devices includes many variables off how to address design issues in the best possible way. The design includes what type of touch interaction method is to be used, how the interface is to be designed and in which context it will be used. The problematic issue that has to be dealt with is how the designer must put together all these parameters into one final product. This paper presents the case of re-designing a touch screen bedside monitor, a device used in hospitals to observe the vital signs of patients. The design solution presented deals with the issues of how the device was designed to suit the users and environment of a hospital. A contextual inquiry showed the many constraints and standards that had to be met and how they shaped the design solution. Earlier work shows the different methods for touch interaction, interface design and feedback that can be applied for touch screen devices. The resulting design is discussed in relation to the different ways of creating touch screen interfaces, and an example of a work method is presented in the end of the paper on how to design for contextual touch screen devises.</p>
133

Countermeasures against railway ground and track vibrations

Hildebrand, Robert January 2001 (has links)
Railway track and ground vibrations are considered, with anemphasis on methods of mitigation ("countermeasures"), forapplication to wayside disturbance problems. Original field measurements from two sites in Sweden, aswell as borrowed measurements from Norway, provide vibrationresults at many points on the track, on and underneath theground surface, for a variety of trains, both with and withoutcountermeasures in-place. Infinite periodic system theory is the basis of track-onlyand track-ground interaction models presented. The repeatingelement includes the sleeper, pad-fastener, rail, and either alocally-reacting ballast or a continuous ballast-soilwaveguide. The track-only model is even refined for nonlinearand high-frequency cases. The models are suitable for studyingcountermeasures in the track, or in the foundation(soil-stabilization). This latter countermeasure is shown to beeffective at low frequencies (of geotechnical interest), butsometimes counterproductive at audible frequencies (disturbanceproblems). An analytical model for hard seismic screens is alsopresented, to complement the treatment of ground vibrationcountermeasures; this is based on physical approximations whichare favored by "high" (i.e, audible)frequencies and softsoils. Notably, experimentally observed resonant behavior isexplained. <b>Keywords:</b>ground vibration, vibration screen, trackvibration, railway vibration
134

Amperometric biosensor based on Prussian Blue nanoparticle-modified screen-printed electrode for estimation of glucose-6-phosphate

Banerjeea, Suchanda, Sarkara, Priyabrata, Turner, Anthony January 2013 (has links)
Glucose-6-phosphate (G6P) plays an important role in carbohydrate metabolism of all living organisms. Compared to the conventional analytical methods available for estimation of G6P, the biosensors having relative simplicity, specificity, low-cost and fast response time are a promising alternative. We have reported a G6P biosensor based on screen-printed electrode utilizing Prussian Blue (PB) nanoparticles and enzymes, glucose-6-phosphate dehydrogenase and glutathione reductase. The PB nanoparticles acted as a mediator and thereby enhanced the rate of electron transfer in a bi-enzymatic reaction. The Fourier transform infrared spectroscopy and energy-dispersive X-ray spectroscopy study confirmed the formation of PB, whereas, the atomic forced microscopy revealed that PB nanoparticles were about 25-30 nm in diameter. Various optimization studies, such as pH, enzyme and cofactor loading, etc. were conducted to obtain maximum amperometric responses for G6P measurement. The developed G6P biosensor showed a broad linear response in the range of 0.01-1.25 mM with a detection limit of 2.3 mM and sensitivity of ­63.3 mA/mM at a signal-to-noise ratio of 3 within 15 s at an applied working potential of -100 mV. The proposed G6P biosensor also exhibited good stability, excellent anti-interference ability and worked well for serum samples.
135

Between You and Me

Stansell, Thomas Micah 21 November 2008 (has links)
In an increasingly online world interpersonal interactions become a less integral part of our cultural make-up. The exploration of this phenomenon is the thematic concept that activates Between You and Me - a triptych-split-screen short film and video installation. This text is dedicated to exploring how theme, technique, and theory are considered in the context of the film, and how character and form (more than narrative) illuminate the thematic concept.
136

Looking Back: An Examination of Family Archives

Bentley, James E, III 07 May 2011 (has links)
With digital technology now dominating the film and photography industry, analog resources are becoming scarce. Simultaneously, memories preserved through personal family archives also are in danger of deterioration. Time, heat and humidity can cause film to decay just as the passage of time and the erosion of memory allows their contents to fade. In Looking Back, my family film and photography archives are exhumed and collectively examined by myself and my family. Reflecting upon this massive accumulation of imagery and their attached memories seems an endless task. However, as expressed in Looking Back, the greater the effort to bring conclusive memories to the surface, the more impossible the task proves to be, and larger questions about the significance of family history result.
137

Contextual design for touch screen devices

Kozuch, Kamil January 2010 (has links)
Designing touch screen devices includes many variables off how to address design issues in the best possible way. The design includes what type of touch interaction method is to be used, how the interface is to be designed and in which context it will be used. The problematic issue that has to be dealt with is how the designer must put together all these parameters into one final product. This paper presents the case of re-designing a touch screen bedside monitor, a device used in hospitals to observe the vital signs of patients. The design solution presented deals with the issues of how the device was designed to suit the users and environment of a hospital. A contextual inquiry showed the many constraints and standards that had to be met and how they shaped the design solution. Earlier work shows the different methods for touch interaction, interface design and feedback that can be applied for touch screen devices. The resulting design is discussed in relation to the different ways of creating touch screen interfaces, and an example of a work method is presented in the end of the paper on how to design for contextual touch screen devises.
138

Dengue Virus Host Factors

Sessions, October Michael January 2009 (has links)
<p>Dengue fever and dengue hemorrhagic fever are estimated to afflict 50-100 million people annually and are caused by one of the four serotypes of dengue virus. Dengue virus is carried and transmitted to humans by mosquitoes of the Aedes genus. Given the broad geographic distribution of Aedes mosquitoes, it has been estimated that nearly half the world's population is at risk of contracting the disease. Currently, no vaccine or specific antiviral treatment is available to combat this emerging menace. </p><p>A greater understanding of how dengue virus interacts with its insect and human hosts will facilitate the intelligent design of specific antivirals to combat the disease and enable the selective breeding of mosquitoes resistant to the virus. Although the genomes of the two primary mosquito vectors have been sequenced, the molecular tools necessary for conducting a systematic genetic analysis of host factors required for DEN infection are not yet available. These tools do however exist in the closely related fruit fly, Drosophila melanogaster. By using a strain of dengue virus that was adapted to propagate in fruit fly cells, we completed a full genetic screen for host factors required for efficient dengue virus propagation. When homologues of these host factors were assayed in a human cell line, over half were also shown to be required for efficient viral propagation. This indicates that while the virus is utilizing many of the same pathways in both of its hosts, the interaction with the insect vector has unique features that may contribute to the observed lack of pathogenesis in mosquitoes.</p> / Dissertation
139

Investigation of Light Induced Degradation in Promising Photovoltaic Grade Si and Development of Porous Silicon Anti-Reflection Coatings for Silicon Solar Cells

Damiani, Benjamin Mark 16 April 2004 (has links)
Cast multi-crystalline silicon substrates are used in more than 50% of the photovoltaic modules produced today. The random grain orientations of multi-crystalline silicon wafers inhibit the formation of an effective surface texturing using conventional techniques. The other main substrate used is single crystalline Czochralski wafers (~30% of the market share). Czochralski silicon material is known to suffer from the formation of a metastable defect under carrier injection, sometimes referred to as light induced degradation (LID). Light induced degradation in low-cost photovoltaic grade silicon is studied. Trap formation is shown to occur at temperatures above 200oC. Efficiency degradation reduced from 0.75% to 0.24% when the cell thickness was reduced from 378 to 157m. The presence of light induced degradation in ribbon silicon solar cells is documented for the first time in this thesis. Trap generation and annihilation are observed in high lifetime regions of multi-crystalline silicon samples. No degradation was observed over a 24-hour period at 25oC in high efficiency ribbon solar cells (>16%), but at an elevated temperature of ~75oC, appreciable efficiency degradation was observed. Czochralski silicon solar cells showed full degradation within 24 hours at 25o C. Part two of this thesis involves the development of a surface texturing suitable for all crystalline silicon. Only 6 to 10 seconds in a 200:1 HF to HNO3 solution at room temperature allows for the formation of an effective porous silicon anti-reflection coating. This resulted in a porous silicon anti-reflection coated solar cell efficiency of 15.3% on a float zone Si sample with an excellent fill factor (78.7%). The typical process used in the literature involves porous silicon etching as the final step in the solar cell fabrication sequence. The major problem associated with this process sequence is fill factor degradation. This problem was overcome in this research by porous silicon etching prior to cell processing. It is shown that incorporating an acid texture prior to porous silicon etching can improve the surface reflectance for cast multi-crystalline and Czochralski silicon samples. Solar cell efficiencies of 14.8% for Cz Si and 13.6% for cast mc-Si were achieved.
140

Forming Screen Effect on Ultrasonic Beam Field

Fouts, John Lyle 21 December 2005 (has links)
The aim of this study was to characterize the interaction between a pulsed ultrasonic wave and a paper forming screen for potential development of a smart paper forming sensor to measure velocity profile of the forming jet as it impinges on the wire. To achieve this goal, a Signal-Processing DOP 2000 pulsed ultrasonic Doppler velocimeter was used to generate a pulsed ultrasonic signal. The signal was transmitted and received using four different ultrasonic transducers: a 2 MHz 10 mm, 4 MHz 5 mm, 4MHz 8 mm focused, and 8 MHz 5 mm. The ultrasonic signals were then analyzed in order to determine the ultrasonic beam echo amplitude and shape. These tests were performed with and without various paper forming screens placed between the ultrasonic transducer and an ultrasonic signal target. Two different paper forming screens were utilized to study the interaction of the ultrasonic beam with the forming screens. The tests showed that the ultrasonic signal passing through the forming screens is greatly attenuated causing a sharp decrease in echo amplitude. To overcome the attenuation of the signal, a much higher amplification of the signal was used causing an increase in the saturation region around the forming screen. This increased the minimum distance that a target had to be away from the forming screen. The closest distance from the plastic sphere to the screen over the widest range of transducer-screen-distances that produced detectable echoes was achieved with the 4 MHz 5 mm transducer. The tests showed for both screens that there is more variation in beam width when the screen is moved laterally than when it is not moved at all. They also show that even though the pores in the forming screen are very small, they seem to have a great effect on the beam width measurements of the ultrasonic transducer.

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