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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.
261

Enhancing Game Jam Experiences: Finding more productive and focused group work interactions through establishing a framework

Hansson, Torsten January 2014 (has links)
The thesis will focus on the methods of establishing group work objectives and in turn create focused groups that spend more time being productive and enjoying their efforts than having to go through trivial yet troublesome organization and structure sorting evaluation periods.
262

Rapid Radio: Analysis-Based Receiver Deployment

Suris Pietri, Jorge Alberto 26 August 2009 (has links)
A large body of work has been produced in the area of productivity enhancers for the design of both Software-Defined Radio and Field Programmable Gate Arrays systems. These tool are created with the goal of aiding the user in the process of instantiating a design. They do not address, however, a specific use-case in which the user does not know or care about what the design of his system is. In this work, analysis-based design is presented and applied to FPGA-based SDRs. The RapidRadio framework abstracts away much of the knowledge required for analyzing an unknown signal and building an FPGA-based receiver. Resource utilization is traded-off for reduced implementation time and increased exibility. Automatic modulation classification is done with blind parameter estimation. Unlike other contemporary work, no a priori knowledge about the signal being classified is assumed. This leads to the development of a system that does not depend on perfect synchronization to classify the signal. A new quasi-generic synchronization architecture that allows the synchronization of multiple modulations schemes is presented. The result of the modulation classification is used to automatically create an FPGA-based radio receiver. / Ph. D.
263

Rapid Prototyping of an FPGA-Based Video Processing System

Shi, Zhun 20 June 2016 (has links)
Computer vision technology can be seen in a variety of applications ranging from mobile phones to autonomous vehicles. Many computer vision applications such as drones and autonomous vehicles requires real-time processing capability in order to communicate with the control unit for sending commands in real time. Besides real-time processing capability, it is crucial to keep the power consumption low in order to extend the battery life of not only mobile devices, but also drones and autonomous vehicles. FPGAs are desired platforms that can provide high-performance and low-power solutions for real-time video processing. As hardware designs typically are more time consuming than equivalent software designs, this thesis proposes a rapid prototyping flow for FPGA-based video processing system design by taking advantage of the use of high performance AXI interface and a high level synthesis tool, Vivado HLS. Vivado HLS provides the convenience of automatically synthesizing a software implementation to hardware implementation. But the tool is far from being perfect, and users still need embedded hardware knowledge and experience in order to accomplish a successful design. In order to effectively create a stream type video processing system as well as to utilize the fastest memory on an FPGA, a sliding window memory architecture is proposed. This memory architecture can be applied to a series of video processing algorithms while the latency between an input pixel and an output pixel is minimized. By comparing my approach with other works, this optimized memory architecture proves to offer better performance and lower resource usage over what other works could offer. Its reconfigurability also provides better adaptability of other algorithms. In addition, this work includes performance and power analysis among an Intel CPU based design, an ARM based design, and an FPGA-based embedded design. / Master of Science
264

Design framework for the graphical user interface of a terminal area air traffic advisory system

Beamon, Courtney A. 18 November 2008 (has links)
The purpose of this research thesis was to develop a framework and methodology for the design of a graphical user interface to be used by air traffic controllers. The interface is intended to be only a part of a complete Advisory System designed to supplement the tasks of terminal area air traffic controllers. This research addresses many of the human factors issues associated with the development of the display. The research takes a user-perspective and applies the principles of rapid prototyping to develop the framework for the design of the interface. Attention is also given to the previous research that explores the implications of automating various air traffic control tasks. Finally, a prototype system was developed to fulfill one of the primary rapid prototyping steps. The prototype displays the general format for the various advisories and presents three typical scenarios where the system may be of particular use. In the future, the prototype can be used to gather additional information on the opinions and requirements of the future system users - air traffic controllers. It is anticipated that moderate benefits can be attained through the implementation of such a system, provided that the interface satisfies the user requirements. / Master of Science
265

A pneumatic conveying powder delivery system for continuously heterogeneous material deposition in solid freeform fabrication

Fitzgerald, Shawn 02 December 2008 (has links)
Great improvements are continuously being made in the solid free form fabrication (SFF) industry in terms of processes and materials. Fully functional parts are being created directly with little, if any, finishing. Parts are being directly fabricated with engineering materials such as ceramics and metals. This thesis aims to facilitate a substantial advance in rapid prototyping capabilities, namely that of fabricating parts with continuously heterogeneous material compositions. Because SFF is an additive building process, building parts layer-by-layer or even point-by-point, adjusting material composition throughout the entire part, in all three dimensions, is feasible. The use of fine powders as its build material provides the potential for the Selective Laser Sintering (SLS), ThreeDimensional Printing (3DP), and Freeform Powder Molding (FPM) processes to be altered to create continuously heterogeneous material composition. The current roller distribution system needs to be replaced with a new means of delivering the powder that facilitates selective heterogeneous material compositions. This thesis explores a dense phase pneumatic conveying system that has the potential to deliver the powder in a controlled manner and allow for adjustment of material composition throughout the layer. / Master of Science
266

Configurable Architecture for System-Level Prototyping of High-Speed Embedded Wireless Communication Systems

Subramanian, Visvanathan 02 October 2003 (has links)
Broadband wireless technologies have the potential to provide integrated data and multimedia services in several niche areas. There is a growing need to develop high-performance communication systems that can satisfy high-end data processing requirements inherent in these technologies. The speed and complexity of these systems necessitates designers to break away from traditional architectures and design methodologies. A more comprehensive and demanding design and verification process including both hardware and software is required. Field-programmable gate arrays (FPGA) offer an attractive alternative to the low efficiency of Digital Signal Processor (DSP) based systems and low flexibility of Application Specific Integrated Circuits(ASIC). The availability of high-density, high-performance field-programmable gate arrays with several capabilities, like embedded memory and advanced routing, together with the adaptability that they offer make them highly desirable for developing hardware prototypes of communication systems. This thesis describes the development of a configurable architecture and FPGA-based design methodology used in the development of a Local Multipoint Distribution Service (LMDS) gateway for a disaster response network. The design of the gateway posed several challenges due to high data rates (120 Mbits/sec) and adaptive features like variable Forward Error Correction Coding and optional link-level retransmissions. The design decisions and simulation results of the verification process are discussed in detail. Finally, the aspects of testing and integration of the prototype in the overall system are discussed. / Master of Science
267

Local Adaptive Slicing for Layered Manufacturing

Tyberg, Justin 02 March 1998 (has links)
Existing layered manufacturing systems fabricate parts using a constant build layer thickness. Hence, operators must compromise between rapid production with large surface inaccuracies, and slow production with high precision, by choosing between thick and thin build layers, respectively. Adaptive layered manufacturing methods alleviate this decision by automatically adjusting the build layer thickness to accommodate surface geometry, thereby potentially enabling part fabrication in significantly less time. Unfortunately, conventional adaptive layered manufacturing techniques are often unable to realize this potential when transitioning from the laboratory to an industrial setting. The problem is that they apply the variable build layer thickness uniformly across each horizontal build plane, applying the same build layer thickness to all parts and part features across that plane even though they have different build layer thickness needs. When this happens, the advantage of using adaptive build layer thicknesses is lost. This thesis demonstrates how to minimize fabrication times when implementing adaptive layered manufacturing. Specifically, it presents a new method in which each part or individual part feature is assigned a distinct, independent build layer thickness according to its particular surface geometry. Additionally, this thesis presents a calibration procedure for the Fused Deposition Modeler (FDM) rapid prototyping system that enables accurate, adaptively sliced parts to be physically realizable. Experimental software has been developed and sample parts have been fabricated to demonstrate both aspects of this work. / Master of Science
268

A Fast-Response Odor Chromatographic Sniffer (FOX)

Chowdhury, Mustahsin 04 November 2024 (has links)
This thesis in microscale gas chromatography (μGC) creates a paradigm shift in rapidly analyzing chemicals in the environment or analytes. We are looking for unexpected chemical changes that have been added purposefully or unintentionally. The work examines various aspects of μGC technology, including the optimization of ionic liquid stationary phase coatings for microfabricated columns, achieving up to 8300 theoretical plates per meter for naphthalene using 1-butylpyridinum bis(trifluoromethylsulfonyl)imide [BPY][NTf2] at 240°C. The development of portable systems for fuel adulteration detection is demonstrated, capable of discriminating 5% kerosene adulterated diesel fuel with four seconds of chromatogram analysis. The research also presents a novel parallel column configuration using three ionic liquid-coated semi-packed columns, each 1 m long and 240 μm deep, for complex gas analysis of up to 46 compounds. Key innovations discussed include optimized coating procedure of GC separation columns and implementation of GC based miniaturized electronic nose with the integration of machine learning algorithms. An evaluation of a prototype modular electric and fluidic μGC was evaluated and validated for benzene toluene, ethylbenzene, and xylene (BTEX). This research highlights the versatility of μGCs in applications ranging from environmental monitoring to quality control in the fuel industry, showcasing their potential as powerful tools for on-site chemical analysis with improved selectivity, resolution, and portability. / Doctor of Philosophy / This thesis advances the development of miniature chemical analytical systems, specifically gas chromatography, which is the gold standard for detecting volatile organic compounds in the environment. The work encompasses comprehensive improvements to these systems, from optimizing fabrication and coating of separation columns for better chemical separation to developing rapid prototyping methods for both hardware and software components. Through the integration of machine learning and innovative system designs, the thesis demonstrates significant improvements in detection capabilities, including identifying fuel tampering within seconds and monitoring harmful air pollutants at parts-per-billion levels over extended periods. These advances pave the way for making sophisticated chemical analysis accessible outside of traditional laboratories, enabling direct testing at locations where immediate results are crucial for safety and quality control.
269

The impact of additive fabrication technologies on Institutional Research Development and the SA product development community-the CRPM story

De Beer, D.J. January 2008 (has links)
Published Aticle / The Centre for Rapid Prototyping and Manufacturing (CRPM) made a humble start in 1997 as a spin-off from a proposed research activity in 1995, at a stage when Technikons were still being seen as occupational training institutions rather than higher education institutions and and as such, were not funded for research. Addressing an area of high importance to the South African industry, the research activity soon grew into a research unit, commercial centre / centre of excellence, technology transfer unit and innovation support centre. Above all, the research started to impact on product development practices to deliver improved products. The paper considers the development of the available technology platforms at the CUT'S CRPM to become a technology power-house on the African continent, and how it impacted on Institutional Research Development in South Africa.
270

Characterization of metal powder based rapid prototyping components with respect to aluminium high pressure die casting process conditions

Pereira, M.F.V.T., Williams, M., Du Preez, W.B January 2010 (has links)
Published Article / This paper is based on tests performed on die component specimens manufactured by EOS-DMLS (direct metal laser sintering) and LENS (laser engineered net shape) RP (rapid prototyping) technology platforms, as well as manufactured specimens machined out of preferred standard hot work steel DIN 1.2344. These specimens resemble typical components used in metal high pressure die casting tool sets. The specimens were subjected to a programme of cyclic immersion in molten aluminium alloy and cooling in water-based die release medium. The heat checking and soldering phenomena were analyzed through periodic inspections, monitoring crack formation and evidence of surface washout. At the end of the thermal tests, mechanical strength and hardness tests were performed to assess toughness and core resistance variations in relation to the initial conditions. Finally metallographic investigations were performed through optical microscopy on all the specimens considered. The outcomes of this research will be presented and used by the CSIR for further development and application of the assessed EOS-DMLS and LENS rapid prototyping technologies in rapid die manufacturing techniques and die design principles, including time and economic feasibility criteria to be applied when considering rapid die manufacture.

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