Predictive multiple suppression methods consist of two main steps: a prediction step, in which multiples are predicted from the seismic data, and a subtraction step, in which the predicted multiples are matched with the true multiples in the data. The last step appears crucial in practice: an incorrect adaptive subtraction method will cause multiples to be sub-optimally subtracted or primaries being distorted, or both. Therefore, we propose a new domain for separation of primaries and multiples via the Curvelet transform. This transform maps the data into almost orthogonal localized events with a directional and spatialtemporal component. The multiples are suppressed by thresholding the input data at those Curvelet components where the predicted multiples have large amplitudes. In this way the more traditional filtering of predicted multiples to fit the input data is avoided. An initial field data example shows a considerable improvement in multiple suppression.

Predictive multiple suppression methods consist of two main steps: a prediction step, in which multiples are predicted from the seismic data, and a subtraction step, in which the predicted multiples are matched with the true multiples in the data. The last step appears crucial in practice: an incorrect adaptive subtraction method will cause multiples to be sub-optimally subtracted or primaries being distorted, or both. Therefore, we propose a new domain for separation of primaries and multiples via the Curvelet transform. This transform maps the data into almost orthogonal localized events with a directional and spatial-temporal component. The multiples are suppressed by thresholding the input data at those Curvelet components where the predicted multiples have large amplitudes. In this way the more traditional filtering of predicted multiples to fit the input data is avoided. An initial field data example shows a considerable improvement in multiple suppression.

When the eye rotates, switching from one fixation point to another, the perception of motion is strongly suppressed and rarely perceived. During these quick ‘saccadic’ eye movements, other aspects of visual perception become suppressed or compressed as well, with certain effects being stronger or weaker along the plane of the saccade - such differences can help identify the underlying neuronal pathways, since some exhibit directional tuning (e.g. neurons projecting from primate V1 to middle temporal area (MT)), and others do not (e.g. relay neurons linking the superior colliculus to area MT). A briefly presented motion probe was placed at a number of points relative to saccade to plot sensitivity to motion along different planes and directions. The results suggest that saccadic motion is suppressed before the eye begins to move, and is applied evenly across planes and directions.

Over the past years, catastrophic dust explosion incidents have caused numerous injuries, fatalities and economical losses. Dust explosions are rapid exothermic reactions that take place when a combustible dust is mixed with air in the presence of an ignition source within a confined space. A variety of strategies are currently available to prevent dust explosion accidents. However, the recurrence of these tragic events confirms flaws in process safety for dust handling industries. This dissertation reports advances in different approaches that can be followed to prevent and mitigate dust explosions. For this research, a 36 L dust explosion vessel was designed, assembled and automated to perform controlled dust explosion experiments. First, we explored the effect of size polydispersity on the evolution of aluminum dust explosions. By modifying systematically the span of the particle size distribution we demonstrated the dramatic effect of polydispersity on the initiation and propagation of aluminum dust explosions. A semi-empirical combustion model was used to quantify the laminar burning velocity at varying particle size. Moreover, correlations between ignition sensitivity and rate of pressure rise with polydispersity were developed. Second, we analyzed the effect of particle size and crystalline levels in the decomposition reactions of explosion inhibitor agents (i.e., phosphates). We fractionated ammonium phosphate- monobasic (NH_4H_2PO_4) and dibasic ((NH_4)_2HPO_4) at different size ranges, and synthesized zirconium phosphate (Zr(HPO_4)_2·H_2O) at varying size and crystalline levels. Particle size was found to be crucial to improve the rate of heat absorption of each inhibitor. A simplified model was developed to identify factors dominating the efficiency of dust explosion inhibitors. Finally, we conducted computational fluid dynamic (CFD) simulations to predict overpressures in dust explosions vented through ducts in large scale scenarios. We particularly focused on the adverse effects caused by flow restrictions in vent ducts. Critical parameters, including ignition position, geometric configuration of the vent duct, and obstructions of outflow such as bends and panels were investigated. Comparison between simulation and experimental results elucidated potential improvements in available guidelines. The theoretical analyses complemented the experimental work to provide a better understanding of the effects of particle size on the evolution of dust explosions. Furthermore, the validation of advanced simulation tools is considered crucial to overcome current limitations in predicting dust explosions in large scale scenarios.

When the eye rotates, switching from one fixation point to another, the perception of motion is strongly suppressed and rarely perceived. During these quick ‘saccadic’ eye movements, other aspects of visual perception become suppressed or compressed as well, with certain effects being stronger or weaker along the plane of the saccade - such differences can help identify the underlying neuronal pathways, since some exhibit directional tuning (e.g. neurons projecting from primate V1 to middle temporal area (MT)), and others do not (e.g. relay neurons linking the superior colliculus to area MT). A briefly presented motion probe was placed at a number of points relative to saccade to plot sensitivity to motion along different planes and directions. The results suggest that saccadic motion is suppressed before the eye begins to move, and is applied evenly across planes and directions.

The general aim of this study was to develop a strategic plan for a company in the dust suppression industry. Currently there is no formal process documented or analysis done within the company regarding strategic planning due to the company being founded, extensive growth taking place year on year and the urgent need for the operations to be established, in order for the company to start selling their products and services. The study was conducted among a sample of 45 junior, middle and senior management employees within this company. The data collected from the participants were collected personally via interviews and a strategic planning questionnaire and recorded electronically by the Statistical Consultation Services at the North–West University and the data were analysed by means of the Statistical Package for Social Sciences (SPSS V18). In addition to the structured questionnaires, management was also interviewed to assess their views on the strategic planning at the company. The results and findings indicated that there was some strategic planning actions lacking and that formal strategic planning that defines objectives and assessment of the various situations within the company, are not properly performed. The author was however able to evaluate and determine where the company is going over the next three years. The study draws a number of conclusions and makes recommendations with regard to strategic planning, one of which is that the company should follow a more structured and formalised approach. / Thesis (M.B.A.)--North-West University, Potchefstroom Campus, 2012.

The general aim of this study was to develop a strategic plan for a company in the dust suppression industry. Currently there is no formal process documented or analysis done within the company regarding strategic planning due to the company being founded, extensive growth taking place year on year and the urgent need for the operations to be established, in order for the company to start selling their products and services. The study was conducted among a sample of 45 junior, middle and senior management employees within this company. The data collected from the participants were collected personally via interviews and a strategic planning questionnaire and recorded electronically by the Statistical Consultation Services at the North–West University and the data were analysed by means of the Statistical Package for Social Sciences (SPSS V18). In addition to the structured questionnaires, management was also interviewed to assess their views on the strategic planning at the company. The results and findings indicated that there was some strategic planning actions lacking and that formal strategic planning that defines objectives and assessment of the various situations within the company, are not properly performed. The author was however able to evaluate and determine where the company is going over the next three years. The study draws a number of conclusions and makes recommendations with regard to strategic planning, one of which is that the company should follow a more structured and formalised approach. / Thesis (M.B.A.)--North-West University, Potchefstroom Campus, 2012.

Thesis (Ph. D.)--University of Missouri--Rolla, 2007. / Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed November 29, 2007) Includes bibliographical references (p. 66-67).

Thesis (Ph. D.)--Auburn University, 2008. / Abstract. Vita. Includes bibliographical references (p. 49-57).

Thesis (Ph.D)--Electrical and Computer Engineering, Georgia Institute of Technology, 2009. / Committee Chair: G. Tong Zhou; Committee Co-Chair: Xiaoli Ma; Committee Member: David V. Anderson; Committee Member: James Stevenson Kenney; Committee Member: Liang Peng; Committee Member: William D. Hunt. Part of the SMARTech Electronic Thesis and Dissertation Collection.