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An experiment was conducted to separate the effects of anxiety relief conditioning from other variables which may be operative within that paradigm. A review of the literature revealed that no definitive investigations had been conducted, and critiques of these investigations were offered. Also, the distinction between aversion relief and anxiety relief conditioning procedures was detailed.

Quality system auditing has been a topic of much recent discussion but there has not been a commensurate amount of research on how the audit process can make more effective use of auditor time and improve the quality of their judgements. An approach certification bodies and their clients may adopt is to measure the quality system activities of the client, and use these measurements (or metrics) to improve their understand of the quality system. If these metrics were available to auditors, they could identify the strengths and weaknesses of the quality system and assist in deciding if the client complies with ISO 9000. This could make the audit process more cost-effective and focused. A detailed study of the current auditing process used by certification bodies, and a survey of auditors, identified the quality system activities that provide the most confidence that the company has a compliant quality system. The "quality loop" activities of internal audit/management review and corrective action were found to be both the most important activities in showing compliance and provide the basis of metrics that can inform the auditor about the state of health of these activities. Metrics capable of measuring the other quality system activities required by ISO 9000 are identified, and their effectiveness in monitoring the quality system is discussed. The research shows that metrics concerned with the quality loop can provide useful information to an auditor and can help them in reaching a judgement. It is also shown that the use of metrics is constrained by organisational and technical factors, such as the size of the organisation being measured and the correspondence between the activity being measured and the requirements of ISO 9000.

Depuis la révolution industrielle, l'Homme développe des systèmes industriels pour satisfaire ses exigences de production. Mais exploiter ces installations n'est pas sans risques pour les utilisateurs. De ce fait, l'analyse des risques s'est largement développée durant ces dernières décennies. En effet, si dans les années 70, les études se focalisaient sur les défaillances technologiques, des accidents ont souligné l'importance des facteurs humains et organisationnels dans leur occurrence. Si bien que dans les années 80, des méthodes consacrées à l'identification de ces facteurs ont émergées. Ces études, impliquant différentes disciplines, étaient jusqu'alors conçues et conduites séparément les unes des autres. Cet état de fait amène à une sectorisation des analyses et ne permet pas d'avoir une vision globale de la situation étudiée. Mais, depuis peu, des méthodologies proposent d'intégrer (partiellement) ces dimensions dans la démarche d'analyse. Le manque d'intégration constitue aujourd'hui une problématique, scientifique et industrielle, pour les exploitants de systèmes critiques. Ainsi, notre contribution porte sur le développement d'une méthodologie permettant l'analyse de risques de systèmes socio-techniques en exploitation. Ce type d'analyse vise à probabiliser le risque à des fins d'aide à la décision. En ce sens, nous proposons une démarche de formalisation, d'intégration, de représentation et de modélisation des différentes connaissances du système. Le modèle présenté permet d'identifier l'ensemble des causes menant à l'occurrence d'un événement critique, en considérant les données techniques du système et les données liées aux opérateurs et à l'organisation. / Since the industrial revolution, human being develops industrial systems to meet his production needs. But the operation of such facilities involves risks for the users. As a result the risk analysis has expanded during these last decades. Indeed, if in the Seventies, the studies were focused on the technological failures, several major accidents have underlined the importance of human and organisational factors in their occurrence, and have changed this initial way of thinking. So that in the Eighties, different methods allowing an identification of these factors have emerged. These studies, implying different fields of expertise, were so far independently built and applied. This fact leads to sector-based analyses and prevents from having an overall view of the studied situation. But, recently, some methodologies propose to (partially) integrate these different methods to study risks in a global approach. This lack of integration constitutes nowadays a scientific and industrial issue for the owners of critical systems. Thus, our contribution concerns the development of a methodology enabling the risk analyses of socio-technical systems in operation. This kind of analysis aims to probabilistically estimate risks for helping the decision-making. In that way, we propose an approach that enables to formalise, integrate, characterise and represent the different knowledge of the system. Our model allows an identification of the whole of the causes that lead to the occurrence of a critical event, by considering the technical data of the system and the data related to human operators and organisational features.

Music has always played a large role in human life. The technology behind the art has progressed and grown over time in many areas, for instance the instruments themselves, the recording equipment used in studios, and the reproduction through digital signal processing. One facet of music that has seen very little attention over time is the ability to transcribe audio files into musical notation. In this thesis, a method of multipitch analysis is used to track multiple simultaneous notes through time in an audio music file. The analysis method is based on autocorrelation and a specialized peak pruning method to identify only the fundamental frequencies present at any single moment in the sequence. A sliding Hamming window is used to step through the input sound file and track through time. Results show the tracking of nontrivial musical patterns over two octaves in range and varying tempos.

This work is aimed at investigating out-of-plane displacement data on the top surface of a loaded composite laminate containing microcracking damage to explore the feasibility of using surface data to locate microcracks in laminates. In this study, finite element models are created for eleven different cross-ply IM7/977-2 laminates with ply numbers varying from four to ten. Here, each ply thickness is 0.127mm, which is the common laminate thickness commercially available for this material system. For each model a range of transverse loadings are applied and the surface displacement data are analyzed along the mid-plane perpendicular to the plane of the crack. The following outof- plane surface data parameters are obtained for each case: the minimal value above the crack tip, the peak value, and the far-field value. The difference in the peak and minimal values for a given loading is important in determining whether or not the optical technique is sensitive enough to resolve the data. The lateral distance to the peak values and the far-field values are also obtained. These distances are important in determining whether or not an optical system can spatially resolve the data. Results suggest that an optical technique such as digital holography could resolve, at a minimum, the data of [0/90/90/0], [0/90/90/90/90/0], and [0/0/90/90/90/90/0/0] laminates subjected to transverse loads of 1000 MPa.

Current sensors employed in medicine are used to detect chemical and biochemical abnormalities. Their applications range from biopsy (brain), enzyme-linked immunosorbent assay (ELISA) (spinal fluid), blood (bio-barcode), and sweat and urine bio-diagnostics where the primary focus is the selection of biomarkers that can pinpoint the occurrence of the disease. Emerging sensors for cholesterol detection are based on enzymatic functions, which degrade these molecules, where the signal can be visualized optically by using a transducer. Cholesterol is a steroid metabolite that is employed for the synthesis of steroid hormones, and the establishment of proper membrane permeability and fluidity. Since cholesterol is insoluble in blood, it is transported in the circulatory system within lipoproteins, complex spherical particles which have an exterior comprising of amphiphilic proteins and lipids with outward-facing surfaces that are water-soluble and inward-facing surfaces that are lipid-soluble. Low-density lipoprotein (LDL) is known as ‘bad’ cholesterol. High-density lipoprotein (HDL) is known as ‘good’ cholesterol. LDL is linked to cardiovascular conditions such as atherosclerosis and hypertension, which ultimately lead to coronary heart disease, myocardial and cerebral infarction (stroke). An appropriate therapeutic response to a sensor system for cholesterol, specifically LDL, detection implicates the design of an implantable system for stimuli-responsive drug release. The proposed system was designed to detect specific biochemical changes by employing nanoparticles made of glyceryl behenate, polyoxyethylene-polyoxypropylene block copolymer, avidin, biotin and anti-beta lipoprotein antibodies as sensors. This was achieved by coating nanoparticles with antibodies specific to the antigen (i.e. LDL) to create an antibody-conjugated antibody conjugated solid lipid nanoparticles (henceforth known as ‘antibody conjugated SLN). Fenofibrate was used as a model drug due to its low water solubility and to its lipophilic properties similar to statins. The antibody conjugated SLNs were of 150nm in size and had a zeta potential of -28mV. Their drug entrapment efficacy was 86%, with a drug release of 16mg/day due to Fickian diffusion and erosion mechanism. The slow release was due semi-crystalline structure determined by XRD and DSC. Antigen responsive hydrogel was designed by incorporation of thiolated antibody conjugated SLN via Traut’s reagents, polyethylene glycol diacrylate, methyl acrylic acid and polyethylene glycol 200. The osmotic pump was designed from polyethylene oxide, ethyl cellulose and mannitol. The drug reservoir was synthesized from ethyl cellulose coated gelatin capsule via coacervation phase separation method. The polymeric tube synthesized from ethyl cellulose, methyl cellulose and castor oil was coated with antigen responsive hydrogel. Ex vivo studies evaluating intravascular stability of the implant in correlation with mechanical analysis indicated the polymeric tube unstable. An 18-gauge catheter was used for forming an infusion tube as a substitute for the polymeric tube. The implant showed a correlation of Korsmeyer-Peppas drug release during in vivo and in vitro studies. A constant drug release of 881μg/day was observed during in vivo. This played a role in reduction of total cholesterol by means of reduction in LDL sub-fractions by 30%; in correlation with LDL particle enhance clearance from the plasma due to SLN-LDL uptake. An increase by 46% in HDL was observed, which correlated to fenofibrate therapeutic effect. Pharmacokinetic analysis indicated improved mean residence time and efficacy. This indicated that the device could be used for delivery of lipophilic drugs and detection of circulating biomarkers.

Faculty of Engineering and the Built Environment, School of Civil Engineering 9311276v / This research project has been prepared to satisfy the requirements of the University of the Witwatersrand, Faculty of Engineering and the Built Environment for the degree of Master of Science (Civil) in Geotechnical Engineering and Materials (50/50). Contained within the project is a review of international past and current tailings facility closure techniques. Guidelines and minimum requirements for successful closure have been developed and are presented.

Introduction: One in 11.5 patients with a thoracic wound has cardiac involvement with potentially life-threatening consequences. Therefore, cardiac injury must be assumed in every patient with a penetrating chest lesion, even if the patient is haemodynamically stable. A need exists to diagnose or screen for “occult” cardiac injury. Methods: A retrospective analysis was conducted in patients with a penetrating injury to the chest at Charlotte Maxeke Johannesburg Academic Hospital Trauma Unit from 1 January 2007 to 30 June 2010. Data was compared between patients with and without cardiac injury. Clinical examination and special investigations were assessed for sensitivity, specificity, positive and negative predictive values. Results: Of 7 781 major injuries assessed, 1 591 (20%) sustained a penetrating injury to the chest. All cardiac injury was incurred through a precordial wound. Two investigations were found to be both significant and useful. Transthoracic echocardiography (TTE) had a sensitivity of 100% and specificity of 95%. Serial Troponin T (Trop T) levels showed a peak at 4 hours and by 6 hours post admission the specificity and negative predictive values were 100%. Conclusion: Of the investigations examined, TTE was found to have the best results. The need for specialised equipment and training make TTE less practical in a resource-limited environment. Serial Trop T shows a high negative predictive value and is a cost effective screening test for penetrating cardiac injury.