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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.
61

SolidWorks Parameterization for Industrial Robot Design

Saiz Sau, Marc January 2010 (has links)
<p>Development of Industrial robots is becoming more expensive and time consuming over the years. A lot of costs are spent in the development, and so it is necessary to improve the conceptual design phase.</p><p> </p><p>This thesis is an object lesson that shows one of the multiple ways to improve the named phase.</p><p>It basically consists on, using a CAD program, build a robot whose parameters have to be modified from a user interface. The parameters to change are the dimensions of the robot’s parts (morphology parameterization) and also the parts to use (topology parameterization), which can be chosen from a large library of different parts.</p><p> </p><p>Some parameters are changed so as the build robot has similar mass properties to a given one, in order to be able to do some tests with it and export the results to improve the real robot. For this reason, in the interface done there is also written some code to get the mass properties of the built robot. Even so, this thesis only shows how to do the named actions but it has not been done any kind of test.</p>
62

Från Excel till Qt : Överföring av interface / Creating an Interface in Qt

Leijon, Jennifer January 2012 (has links)
Ett användarinterface i Excel kan återskapas på ett strukturerat sätt i Qt. Programmet Qt är lättanvänt för någon med programmeringserfarenhet, men svårt för andra. Qt finns som gratisversion och är baserat på programspråket C++. Tågföretaget Bombardier använder ett interface i Excel, men med nya versioner av programmet har problem uppstått. I detta projekt undersöks svårighetsgraden av Qt och delar av Excel-interfacet återskapas i Qt. Först skapades en design i Qt med bland annat tryckknappar, komboboxar och textfält. Sedan skrevs kod för designens funktion. Slutligen sammanfogades interfacets delar och testkördes.
63

INTEGRATING IPTV AND SOCIAL NETWORKING WITH VOICE INPUT

2013 June 1900 (has links)
Elderly people comprise the highest proportion of television viewers. Elderly people often struggle with new technology and reject it due to complexity. We propose a system to help people keep up with certain new technologies, such as IPTV and social networks with reduced efforts. We specifically propose a system to integrate IPTV with Twitter, a social networking website with an aid of a mobile phone. The system uses speech to text technology on mobile phone, as input to reduce the difficulty involved in the interaction with Twitter, while viewing television. As speech is a more convenient and natural way of expression than text, we anticipate that people from other age groups can also benefit from the system.
64

Static Reservoir Model Upgridding and Design of User Interface

Du, Song 2009 December 1900 (has links)
The development of fine grid geolgocial models has attracted great attention in the past decades. Meanwhile, the need for reliable upscaling and coarsening techniques is continuing. Besides the computational efficiency, upscaling can also offer other advantages. The desire for the assessment of risk and uncertainty in reservoir performance is another key issue that is attracting the researchers. Predictions are necessarily of a statistical character because uncertainty is involved in almost all the aspects of the reservoir characterization. Significantly upscaled models are desired when the full assessment of project risk and uncertainty are to be accomplished. The problem of upgridding fine scale models into the coarsened ones is still an attractive and challenging topic demanding much more effort in the reservoir simulation field. We proposed a modified static coarsening algorithm that has better performance without introducing extra computation cost. This algorithm combines adjacent layers based on static calculations such that the heterogeneity measure of a defined static property is minimized within the layers. In addition, the geological model coarsening will also rely on preserving geological marker information. This combination of static calculation and geological information enables this algorithm to generate models more closely to the true ones. The power and utility of our approaches have been demonstrated using both synthetic and field examples. To assist the optimal coarsening procedures, we developed and implemented a GUI (Graphical User Interface), named MARS. We focused on building up a C++ based user interface which enables users to handle access the upgridding simulation visually. This MARS software package is a general purpose GUI for applications that make use of graphs as an underlying data model. MARS, which allows user to create simulation cases, import and modify data, and generate graphical geological figures, is developed to facilitate the operation of this coarsening procedures and the interpretation of the results obtained by this model. The user of MARS will be graphically guided through the entire process of creating coarsening simulations.
65

Mechanical Properties and Radiation Tolerance of Metallic Multilayers

Li, Nan 2010 May 1900 (has links)
High energy neutron and proton radiation can induce serious damage in structural metals, including void swelling and embrittlement. Hence the design of advanced metallic materials with significantly enhanced radiation tolerance is critical for the application of advanced nuclear energy systems. The goals of this dissertation are to examine the fundamental physical mechanisms that determine the responses of certain metallic multilayers, with ultra-high density interface structures, to plastic deformation and high fluence He ion irradiation conditions. This dissertation focuses on the investigation of mechanical and radiation responses of Al/Nb and Fe/W multilayers. Radiation induced microstructural evolution in Cu and Cu/Mo multilayer films are briefly investigated for comparisons. Al/Nb multilayer films were synthesized by magnetron sputtering at room temperature. The interface is of Kurdjumov-Sachs orientation relationship. In situ nanoindentation inside a transmission electron microscope (TEM) reveal that interfaces act as strong barriers for dislocation transmission and dislocations climb along the Al/Nb interfaces at a much higher velocity than in bulk. The evolution of microstructure and mechanical properties of Al/Nb multilayers has been investigated after helium ion irradiations: 100 keV He+ ions with a dose of 6x10^16/cm2. When layer thickness, h, is greater than 25 nm, hardness barely changes, whereas radiation hardening is more significant at smaller h. This study shows that miscible fcc/bcc interface with large positive heat of mixing is not stable during ion irradiation. In parallel we investigate sputtered Fe/W multilayers. Film hardness increases with decreasing h, and approaches a maximum of 12.5 GPa when h = 1 nm. After radiation, radiation hardening is observed in specimens when h >/= 5 nm, however, hardness barely changes in irradiated Fe/W 1 nm specimens due to intermixing. In comparison, Cu/Mo 5 nm multilayers with immiscible interface has also been investigated after helium ion irradiations. Interfaces exhibit significantly higher helium solubility than bulk. He/vacancy ratio affects the formation and distribution of He bubbles. The greater diameter of He bubbles in Cu than Mo originates from the ease of bubble growth in Cu via punching of interstitial loops. Finally, helium bubble migration and growth mechanisms were investigated in irradiated Cu (100) single crystal films via in situ heating inside a TEM. The activation energy for bubble growth is ~ 0.02 eV at low temperature. At higher temperatures, the activation energy for bubble coalescence is ~ 0.22 eV inside crystal, and 0.34 eV close to surface. The migration mechanisms of helium bubbles involve continuous as well as Brownian movement.
66

Out of plane screening and dipolar interaction in heterostructures /

Chan, Cheung. January 2009 (has links)
Includes bibliographical references (p. 52-53).
67

The Design and Control of Stability and Magnetic Properties of Imaging Nanoparticles

Yoon, Ki Youl 05 February 2013 (has links)
There is significant interest in applying nanoparticle (NP) science to subsurface reservoirs to facilitate oil and gas recovery, image subsurface reservoirs, aid sequestration of CO2 and benefit environmental remediation. Imaging nanoparticles have been designed with long-term dispersion stability in brine and minimal retention in reservoir rock and with preferential adsorption at oil-water interfaces. Polymer-stabilized nanoparticles provide sufficient electrostatic repulsion for high colloidal stability, as characterized by the zeta potential. The small size of the clusters, superparamagnetic properties, and high salt tolerance are highly beneficial in various applications including magnetomotive and electromagnetic imaging and mapping of petroleum reservoirs. Superparamagnetic nanoclusters may be used in imaging in biomedicine and in mapping of petroleum reservoirs, by generating either ultrasonic or acoustic signals with oscillating magnetic motion. For a given magnetization per weight of iron oxide, nanoclusters with sub ~100 nm diameters experience a much larger magnetic force than that of the primary sub- 10 nm primary particles. Aqueous dispersions of 0.1-0.2 wt% superparamagnetic iron oxide nanoclusters were stabilized with citric acid, poly(acrylic acid) (PAA), or poly(styrene sulfonate-alt-maleic acid) (PSS-alt-MA) on the particle surface, with a high loading of ~90% iron oxide. For nanoclusters with only 12% (w/w) PSS-alt-MA electrosteric stabilization was sufficient even in 8 wt% NaCl. Both PAA and PSS-alt-MA were used to stabilize nanoclusters with controlled size during synthesis in aqueous media. To obtain a permanent coating on the surface of clusters cross-linking of the polymer for different cross-linking densities was applied. In this general and highly flexible approach, iron oxide nanoparticles may be formed with an adsorbed polymer stabilizer, which is then permanently bound to the surface via cross-linking. To investigate interfacial activity of nanoparticles, oil-in-water emulsions were stabilized with iron oxide nanoclusters or graphene oxide platelets. In each case, the stabilization was achieved by designing the hydrophilic/hydrophobic nature of surface coating. For oil/water emulsions, the droplet size was as low as ~1 micron diameter, and strongly shear-thinning rheology was observed. A series of sub-100 nm superparamagnetic iron oxide nanoparticles with amphiphilic poly(acrylic acid-b-butylacrylate), (PAA-b-PBA) copolymer shells was synthesized to investigate the effect of the polymer structure on the interfacial tension for nanoparticles adsorbed at the dodecane-water interface. Large reductions in interfacial tension of up to 27.6 mN/m were obtained for a 0.27 wt% nanoparticle concentration indicating significant nanoparticle adsorption and interaction with the oil and water molecules at the interface. The adsorption energy of the polymer-coated nanoparticles at the dodecane/water interface was determined from the interfacial tension and nanoparticle radius, and analyzed in terms of the structure of the polymer stabilizer. Furthermore, oil-in-water emulsions stabilized with graphene oxide nanoplatelets were found to remain stable for several months even at high salinity (up to 5 wt% NaCl, for pH = 2 to 10). The droplet sizes were as small as ~1 μm with a low nanoplatelet concentration of 0.2 wt%. / text
68

A WiFi Tracking Device Printed Directly on Textile for Wearable Electronics Applications

Krykpayev, Bauyrzhan 12 1900 (has links)
Wearable technology is quickly becoming commonplace in our everyday life - fit-ness and health monitors, smart watches, and Google Glass, just to name a few. It is very clear that in near future the wearable technology will only grow. One of the biggest wearable fields is the E-textiles. E-textiles empower clothes with new functionality by enhancing fabrics with electronics and interconnects. The main obstacle to the development of E-textile field is the relative difficulty and large tolerance in its manufacturing as compared to the standard circuit production. Current methods such as the application of conductive foils, embroidering of conductive wires and treatment with conductive coatings do not possess efficient, fast and reliable mass production traits inherent to the electronic industry. On the other hand, the method of conductive printing on textile has the potential to unlock the efficiency similar to PCB production, due to its roll-to-roll and reel-to-reel printing capabilities. Further-more, printing on textiles is a common practice to realize graphics, artwork, etc. and thus adaptability to conductive ink printing will be relatively easier. Even though conductive printing is a fully additive process, the end circuit layout is very similar to the one produced via PCB manufacture. However, due to high surface roughness and porosity of textiles, efficient and reliable printing on textile has remained elusive. Direct conductive printing on textile is possible but only on specialized dense and tightly interwoven fabrics. Such fabrics are usually uncommon and expensive. Another option is to employ an interface layer that flattens the textile surface, thus allowing printing on it. The interface layer method can be used with a variety of textiles such as polyester/cotton that can be found in any store, making this method promising for wearable electronics. Very few examples and that too of simple structures such as a line, square patch or electrode have been reported which utilize an interface layer [1{13]. No sophisticated circuit or a system level design involving integration of components on textile has been demonstrated in this medium before. This work, for the first time, demonstrates a complete system printed on a polyester/cotton T-shirt, that helps in tracking the person who is wearing that T-shirt through a smart phone or any Internet enabled device. A low cost dielectric material (Creative Materials 116-20 Dielectric ink) is used to print the interface layer through manual screen printing method. The circuit layout and antenna have been ink-jet printed with silver nano-particles based conductive ink. Utilizing WiFi technology, this wearable tracking system can locate the position of lost children, senior citizens, patients or people in uniforms, lab coats, hospital gowns, etc. The device is small enough (55 mm x 45 mm) and light weight (10.5g w/o battery) for people to comfortably wear it and can be easily concealed in case discretion is required. Field tests have revealed that a person can be localized with up to 8 meters accuracy and the device can wirelessly communicate with a hand-held receiver placed 55 meters away. Future development of the method with techniques such as automated screen printing, pick and place components, and digital ink-jet printing can pave the way for mass production.
69

The electronic structure of gold-induced reconstructions on vicinal silicon(111)

Moran, John Thomas January 1995 (has links)
No description available.
70

Pictoral interfaces to data bases

Najah, M. January 1986 (has links)
No description available.

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