Coping strategies represent the efforts, both behavioural and cognitive, that people invest in order to deal with stressful encounters. Coping is a basic component for developing adaptation and plays a major role in the relationship between the individual and the environment, especially as a moderating element between stress and sickness. Against this backdrop of the impact that the well-being of employees has on organisations, it is of the essence that organisations need to understand how their members cope with the demands which the organisation places on them. This understanding can assist organisations to evaluate the resources they make available to help employees to cope more positively with the demands placed upon them. The general objective of this study was to investigate the psychometric properties of the Coping Orientations to the Problems Experienced Questionnaire (COPE) within different occupational groups in South Africa, to examine the construct equivalence and to assess reliability. A swey design was used. Random samples (N = 3178) were taken from electricity supply personnel, nurses and police officials, and the COPE was administered. Descriptive statistics, exploratory factor analysis and multivariate analysis of variance (MANOVA) were used to analyse the data. Exploratory factor analysis, using principal axis factoring with varimax rotation, was conducted on 53 items of the COPE and revealed four interpretable factors (Factor 1 = Approach Coping; Factor 2 = Avoidance; Factor 3 = Seeking Support; and Factor 4 = Turn to Religion). Highly acceptable Tucker's phi coefficients were found for all the comparisons, and therefore, sufficient evidence for the construct equivalence of the COPE was demonstrated. Alpha coefficients, ranging from 0,85 to 0,92, were obtained. Statistically significant differences were found between the coping strategies employed within the different organisational, gender and language groups. Recommendations for future research were made. / Thesis (M.A. (Industrial Psychology))--North-West University, Potchefstroom Campus, 2007.

This research project discusses the life-cycle analysis of wind turbines through the processing of operational data from two modern European wind farms. A methodology for SCADA data processing has been developed combining previous research findings and in-house experience followed by statistical analysis of the results. The analysis was performed by dividing the wind turbine into assemblies and the failures events in severity categories. Depending on the failure severity category a different statistical methodology was applied, examining the reliability growth and the applicability of the “bathtub curve” concept for wind turbine reliability analysis. Finally, a methodology for adapting the results of the statistical analysis to site-specific environmental conditions is proposed.

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Detecting ambiguity is essential for successful communication. Two studies investigated whether preschool- (4- to 5-year-old) and school-age (6- to 7-year-old) children show sensitivity to communicative ambiguity and can use this cue to determine which speakers constitute valuable informational sources. Children were provided clues to the location of hidden dots by speakers who varied in clarity and accuracy. Subsequently, children decided from whom they would like to receive additional information. In Study 1, preschool- (n=40) and school-age (n=42) children preferred to solicit information from unambiguous than from ambiguous speakers. However, ambiguous speakers were preferred to speakers who provided inaccurate information. In Study 2, when not provided with information about the outcome of the speakers’ clues, school-age (n=22), but not preschool-age (n=19), children preferred unambiguous relative to ambiguous speakers. Results highlight a developmental progression in children’s use of communicative ambiguity as a cue to determining which individuals are preferable informants.

Deregulated and competitive power market places utilities under high pressure to assure providing power with a satisfactory level of power continuity. This objective entails a high level of reliability which in turn demands a high financial budget for design, operation, and maintenance. Therefore, the need for utilities to balance these factors has been increasing to become the core of a utility's asset management activities. Maintenance is a key aspect of asset management. The main objective of maintenance is to extend the lifetime of equipment and/or reduce the probability of failure. Maintenance activities play an important role in improving system reliability by keeping the condition of a system's equipment within an acceptable level. Generally speaking, technical requirements and budget constraints are the most influential factors in assigning maintenance activities. The most cost-effective maintenance approach is the approach that can sustain a high level of reliability while maintenance cost is minimized. The transformer has a significant role in the power system due to its remarkable effect on the overall level of reliability in addition to its extensive investments in the power grid. Transformer management is comprised of identifying the appropriate type and frequency to maintain the transformer, and the appropriate time to replace the transformer in a cost-effective manner. The essential objective of this thesis is to introduce a novel framework for transformer management. An approach which links maintenance and replacement decisions is presented in this thesis. This approach proposes a methodical decision-making system to determine the optimal time to replace the transformer. Indeed, the proposed approach essentially investigates the cost-effectiveness of replacing the transformer both before and after the lifetime is extended by maintenance. To properly investigate the effect of maintenance, maintenance activities should first be scheduled effectively. Therefore, this approach introduces a maintenance strategy based on reliability-centered maintenance (RCM) concept and genetic algorithm (GA) to optimally schedule maintenance activities. Two replacement studies are conducted: with and without the effect of maintenance. A comparison between replacement studies is discussed in the proposed approach.

Within the scope of this thesis, a reliability based risk assessment, based on Monte Carlo simulation was used to analyse the safety levels of Esenk&ouml / y Fishery Harbor main breakwater, Sea of Marmara, Turkey. In the past, in reliability-based risk assessment methodology in Turkey, the design conditions were only wave characteristics, tidal range, storm surge, wave set-up and the structural system parameters. However in this study, the tsunami risk which was considered as a major design parameter is included in the computations. In this study, development of a structural stability criterion in coastal engineering was suggested to achieve a common definition of reliability including the tsunami risk. The model introduced in this study is a practical technique in the reliability-based risk assessment of breakwaters subject to tsunami risk. In order to determine the occurrence probability of design condition, which is a function of storm waves, tidal range, storm surge and tsunami height, the Monte Carlo simulation, was applied. From the reliability-based risk assessment model applied to Esenk&ouml / y Fishery Harbor as a pilot study in Turkey it was found that, inclusion of the tsunami risk increases the failure risk of the structure, and as lifetime of the structure increases, the impact of tsunami risk on the failure mechanism is more reflected. For Esenk&ouml / y Fishery Harbor main breakwater, tsunami was not the key design parameter when compared to storm waves. However, in regions with great seismic activity, tsunami risk may be very noteworthy depending on the frequency and the magnitude of the tsunami.

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Performance-based earthquake engineering is an emerging field of study that complements the prescriptive methods that the design codes provide to ensure adequate seismic performance of structures. Accounting for uncertainties in the performance assessments forms an important component in this area. In this context, the present study focuses on two broad themes; first, treatment of uncertainties and the application of the first-order reliability method (FORM) in finite-element reliability analysis, and second, the seismic risk assessment of reinforced concrete structures for performance states such as, collapse and monetary loss. In the first area, the uncertainties arising from inherent randomness (“aleatory uncertainty”) and due to the lack of knowledge (“epistemic uncertainty”) are identified. A framework for the separation of these uncertainties is proposed. Following this, the applicability of FORM to the linear and nonlinear finite-element structural models under static and dynamic loading is investigated. The case studies indicate that FORM is applicable for linear and nonlinear static problems. Strategies are proposed to circumvent and remedy potential challenges to FORM. In the case of dynamic problems, the application of FORM is studied with an emphasis on cumulative response measures. The limit-state surface is shown to have a closed and nonlinear geometric shape. Solution methods are proposed to obtain probability bounds based on the FORM results. In the application-oriented second area of research, at first, the probability of collapse of a reinforced concrete frame is assessed with nonlinear static analysis. By modelling the post-failure behaviour of individual structural members, the global response of the structure is estimated beyond the component failures. The final application is the probabilistic assessment of monetary loss for a high-rise shear wall building due to the seismic hazard in the Cascadia subduction zone. A 3-dimensional finite-element model of the structure with nonlinear material models is subjected to stochastic ground motions in the reliability analysis. The parameters for the stochastic ground motion model are developed for Vancouver, Canada. Monetary losses due to the damage of structural and non-structural components are included.