Thesis submitted in fulfilment of the requirements for the degree Magister Technologiae: Discipline Electrical Engineering in the Faculty of Engineering at the Cape Peninsula University of Technology 2008 / As one of the biggest developing country in the world, South Africa is developing very fast resent years. The country’s industrialization process is rapidly evolved. The manufacturing industry as one of the most important sections of the industrialization is playing a very heavy role in South Africa’s economic growth. Big percentage of population is involved in the manufacturing industry. It is necessary to keep and enhance the competitiveness of the South Africa’s manufacturing industry in the world wide. But the manufacturing companies are facing with unpredictable market demands and global competitions. To overcome these challenges, the manufacturing companies need to produce new products which can cater to the market demand as soon as possible. Reconfigurable Manufacturing System (RMS) is one of the possible solutions for the manufacturing companies to produce the suitable product for the market in a short period of time with low cost and flexibility. That is because the RMS can be reconfigured easily according to the required specifications for manufacturing the appropriate product for the market and with above mentioned characteristics. Now, RMS is considered as one of the promising concepts for mass production. As one of the very latest research fields, many companies, universities and institutions have been involved to design and develop RMSs. South Africa as one of the most important manufacturing country in the world, her own universities and researchers has the obligation to study this field and follow the newest development steps. In this project, a lab-scaled reconfigurable plant and a Field Programmable Gate Array (FPGA) technology based reconfigurable controller are used to realize and verify the concepts of the RMS in order to find the methodology of developing RMSs. The lab-scaled reconfigurable plant can be reconfigured into the inverted pendulum and the overhead crane. Although it is not used for manufacturing purpose, it can be used to verify the RMS concepts and the control strategies applied to it. Furthermore, control of the inverted pendulum and the overhead crane are both typical problems in the control field. It is meaningful to develop the controllers for them. As the reconfigurable plant is configured, the reconfigurable controller is reconfigured synchronously in order to produce the proper control signal for the reconfigured plant. In this project, both linear and nonlinear control strategies are deployed. Good results are received. The outcomes of the project are mainly for the education and fundamental research purposes, but the developed control strategies have significant sense towards the military missile guidance and the overhead crane operation in industry.

A transient fault in an array of processing elements results in an inconsistent or incorrect state in the processing element. If the erroneous information has already propagated before detection occurs, then the neighboring processing elements can also be in an incorrect state. Restarting the computation from the beginning every time a transient fault occurs is not only very inefficient but, in real-time computations, may not be possible. This thesis suggests the idea of "rollback" to recover from transient faults. Rollback is done by saving the state of the processing element at different instants of time. When an error is detected, backtracking is done to a consistent state and computation resumes from that state. The rollback algorithm is distributed in nature so that there is no single point of failure in the fault recovery mechanism. / Master of Science

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This research is the array processing help wireless communication techniques to increase the signal accuracy. This technique has an important part of prevalent applications. The wireless communication system, radar, and sonar. Beamforming is one of methods in array processing that filters signals based on their capture time at each element in an array of antennas spatially. Numerous studies in adaptive array processing have been proposed in the last several decades, which are divided in two parts. The first one related to non-adaptive beamforming techniques and the next one related to digitally adaptive Beamforming methods. The trade-off between computational complexity and performance make them different. In this thesis, we concentrate on the expansion of array processing algorithms in both non-adaptive and adaptive ones with application of beamforming in 4G mobile antenna and radar systems. The conventional and generalized side-lobe canceller (GSC) structures beamforming algorithms were employed with a phase array antenna that changed the phase of arrivals in array antenna with common phased array structure antennas. An eight-element uniform linear array (ULA), consisting of di-pole antennas, represented as the antenna array. An anechoic chamber measures the operation of beamforming algorithms performance. An extended modified Kaiser weighting function is proposed to make a semi-adaptive structure in phased array beamforming. This technique is extended to low complexity functions like hyperbolic cosine and exponential functions. Furthermore, these algorithms are used in GSC beamforming. The side-lobe levels were so lower than other algorithms in conventional beamforming around -10 dB. On the other hand, a uniform linear arrays for smart antenna purposes designed to utilize in implementing and testing the proposed algorithms. In this thesis, performance of smart antenna with rectangular aperture coupled microstrip linear array which experimental investigations carried out for obtaining X-band operation of rectangular microstrip antenna by using aperture coupled feeding technique. Frequency range set at approximately 8.6 to 10.9 GHz, by incorporating frequency range of the antenna resonates for single wideband with an impedance bandwidth of 23%. The enhancement of impedance bandwidth and gain does not affect the nature of broadside radiation characteristics. This thesis describes the design, operation, and realization of the beamforming such as Sidelobe level (SLL) control and null forming array antenna are examined with the prototype. An antenna radiation pattern beam maximum can be simultaneously placed towards the intended user or Signal of interest (SOl), and, ideally nulls can be positioned towards directions of interfering signals or signals not of interest (SNOIs). Finally, we focused on the adaptive digitally algorithms in compact antenna that faces with mutual coupling. The variable step-size normalized lease mean square (VS-NLMS) algorithm is implemented in beamforming. This algorithm utilizes continuous adaptation. The weights are attuned that the final weight vector to the most satisfied result. The gradient vector can be achieved by iterative beamforming algorithm from the available data. This algorithm is compared with LMS, NLMS, VSS-NLMS algorithms, it is determined that the VSS-NLMS algorithm is better performance to other algorithms. Finally, we introduced novel adaptive IP-NNLMS beamformer. This beamformer reaches to faster convergence and lower error floor than the previous adaptive beamformers even at low SNRs in presence of mutual coupling. The experimental results verified the simulation results that the proposed technique has better performance than other algorithms in various situations. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2016. / FAU Electronic Theses and Dissertations Collection

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Indiana University-Purdue University Indianapolis (IUPUI) / In general, profiling sensors are low-cost crude imagers that typically utilize a sparse detector array, whereas traditional cameras employ a dense focal-plane array. Profiling sensors are of particular interest in applications that require classification of a sensed object into broad categories, such as human, animal, or vehicle. However, profiling sensors have many other applications in which reliable classification of a crude silhouette or profile produced by the sensor is of value. The notion of a profiling sensor was first realized by a Near-Infrared (N-IR), retro-reflective prototype consisting of a vertical column of sparse detectors. Alternative arrangements of detectors have been implemented in which a subset of the detectors have been offset from the vertical column and placed at arbitrary locations along the anticipated path of the objects of interest. All prior work with the N-IR, retro-reflective profiling sensors has consisted of wired detectors. This thesis surveys prior work and advances this work with a wireless profiling sensor prototype in which each detector is a wireless sensor node and the aggregation of these nodes comprises a profiling sensor’s field of view. In this novel approach, a base station pre-processes the data collected from the sensor nodes, including data realignment, prior to its classification through a back-propagation neural network. Such a wireless detector configuration advances deployment options for N-IR, retro-reflective profiling sensors.