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.

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.

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

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

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

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

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

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.

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.

This dissertation focuses on how requirements for a new software development system are elicited and what pitfalls could cause a software development project to fail if the said requirements are not captured correctly. A number of existing requirements elicitation methods, namely: JAD (Joint Application Design), RAD (Rapid Application Development), a Formal Specifications Language (Z), Natural Language, UML (Unified Modelling Language) and Prototyping are covered. The aforementioned techniques are then integrated into existing software development life cycle models, such as the Waterfall model, Rapid Prototyping model, Build and Fix model, Spiral model, Incremental model and the V-Process model. Differences in the domains (knowledge and experience of an environment) of a client and that of the software development team are highlighted and this is done diagrammatically using the language of Venn diagrams. The dissertation also refers to a case study highlighting a number of problems during the requirements elicitation process, amongst other the problem of tacit knowledge not surfacing during elicitation. Two new requirements elicitation methodologies are proposed namely: the SRE (Solitary Requirements Elicitation) and the DDI (Developer Domain Interaction) methodology. These two methods could potentially be more time consuming than other existing requirements elicitation methods, but the benefits could outweigh the cost of their implementation, since the new proposed methods have the potential to further facilitate the successful completion of a software development project. Following the introduction of the new requirements elicitation methods, they are then applied to the aforementioned case study and highlight just how the hidden domain of the client may become more visible, because the software development team has gained a deeper understanding of the client’s working environment. They have therefore increased their understanding of how the final product needs to function in order to fulfil the set out requirements correctly. Towards the end of the dissertation a summary and a conclusion as well as future work that could be undertaken in this area are provided. / Computer Science / M. Sc. (Computer Science)