Reliability analysis and economic equipment replacement appraisal for substation and sub-transmission systems with explicit inclusion of non-repairable failures

The modern society has come to expect the electrical energy on demand, while many of the facilities in power systems are aging beyond repair and maintenance. The risk of failure is increasing with the aging equipments and can pose serious consequences for continuity of electricity supply. As the equipments used in high voltage power networks are very expensive, economically it may not be feasible to purchase and store spares in a warehouse for extended periods of time. On the other hand, there is normally a significant time before receiving equipment once it is ordered. This situation has created a considerable interest in the evaluation and application of probability methods for aging plant and provisions of spares in bulk supply networks, and can be of particular importance for substations. Quantitative adequacy assessment of substation and sub-transmission power systems is generally done using a contingency enumeration approach which includes the evaluation of contingencies, classification of the contingencies based on selected failure criteria. The problem is very complex because of the need to include detailed modelling and operation of substation and sub-transmission equipment using network flow evaluation and to consider multiple levels of component failures. In this thesis a new model associated with aging equipment is developed to combine the standard tools of random failures, as well as specific model for aging failures. This technique is applied in this thesis to include and examine the impact of aging equipments on system reliability of bulk supply loads and consumers in distribution network for defined range of planning years. The power system risk indices depend on many factors such as the actual physical network configuration and operation, aging conditions of the equipment, and the relevant constraints. The impact and importance of equipment reliability on power system risk indices in a network with aging facilities contains valuable information for utilities to better understand network performance and the weak links in the system. In this thesis, algorithms are developed to measure the contribution of individual equipment to the power system risk indices, as part of the novel risk analysis tool. A new cost worth approach was developed in this thesis that can make an early decision in planning for replacement activities concerning non-repairable aging components, in order to maintain a system reliability performance which economically is acceptable. The concepts, techniques and procedures developed in this thesis are illustrated numerically using published test systems. It is believed that the methods and approaches presented, substantially improve the accuracy of risk predictions by explicit consideration of the effect of equipment entering a period of increased risk of a non-repairable failure.

Does institutional location protect from political influence? the case of a minimum labour standards enforcement agency in Australia

Among the many factors that influence enforcement agencies, this article examines the role of the institutional location (and independence) of agencies, and an incumbent government's ideology. It is argued that institutional location affects the level of political influence on the agency's operations, while government ideology affects its willingness to resource enforcement agencies and approve regulatory activities. Evidence from the agency regulating minimum labour standards in the Australian federal industrial relations jurisdiction (currently the Fair Work Ombudsman) highlights two divergences from the regulatory enforcement literature generally. First, notions of independence from political interference offered by institutional location are more illusory than real and, second, political need motivates political action to a greater extent than political ideology.

Communicating assessment criteria is not sufficient for influencing students' approaches to assessment tasks – perspectives from a differential equations class

This report presents the findings of an exploratory study into the perceptions held by students regarding the use of criterion-referenced assessment in an undergraduate differential equations class. Students in the class were largely unaware of the concept of criterion referencing and of the various interpretations that this concept has among mathematics educators. Our primary goal was to investigate whether explicitly presenting assessment criteria to students was useful to them and guided them in responding to assessment tasks. Quantitative data and qualitative feedback from students indicates that while students found the criteria easy to understand and useful in informing them as to how they would be graded, the manner in which they actually approached the assessment activity was not altered as a result of the use of explicitly communicated grading criteria.

An interview with sound artist Guy Webster by Jillian Hamilton and Jeremy Yuille

Guy Webster is a sound artist who has been featured in numerous festivals, galleries, conferences and theatres in Australia, Japan, UK and Europe. As part of the Transmute Collective he developed the immersive soundscape of Intimate Transactions. On 2nd November, 2005 Jilliann Hamilton and Jeremy Yuille met with Guy Webster to discuss his approach to immersion in soundsapes.

Damage detection in truss bridges using vibration based multi-criteria approach

This paper uses dynamic computer simulation techniques to develop and apply a multi-criteria procedure using non-destructive vibration-based parameters for damage assessment in truss bridges. In addition to changes in natural frequencies, this procedure incorporates two parameters, namely the modal flexibility and the modal strain energy. Using the numerically simulated modal data obtained through finite element analysis of the healthy and damaged bridge models, algorithms based on modal flexibility and modal strain energy changes before and after damage are obtained and used as the indices for the assessment of structural health state. The application of the two proposed parameters to truss-type structures is limited in the literature. The proposed multi-criteria based damage assessment procedure is therefore developed and applied to truss bridges. The application of the approach is demonstrated through numerical simulation studies of a single-span simply supported truss bridge with eight damage scenarios corresponding to different types of deck and truss damage. Results show that the proposed multi-criteria method is effective in damage assessment in this type of bridge superstructure.

Exploration and optimization of user experience in viewing videos on a mobile phone

Compared with viewing videos on PCs or TVs, mobile users have different experiences in viewing videos on a mobile phone due to different device features such as screen size and distinct usage contexts. To understand how mobile user’s viewing experience is impacted, we conducted a field user study with 42 participants in two typical usage contexts using a custom-designed iPhone application. With user’s acceptance of mobile video quality as the index, the study addresses four influence aspects of user experiences, including context, content type, encoding parameters and user profiles. Accompanying the quantitative method (acceptance assessment), we used a qualitative interview method to obtain a deeper understanding of a user’s assessment criteria and to support the quantitative results from a user’s perspective. Based on the results from data analysis, we advocate two user-driven strategies to adaptively provide an acceptable quality and to predict a good user experience, respectively. There are two main contributions from this paper. Firstly, the field user study allows a consideration of more influencing factors into the research on user experience of mobile video. And these influences are further demonstrated by user’s opinions. Secondly, the proposed strategies — user-driven acceptance threshold adaptation and user experience prediction — will be valuable in mobile video delivery for optimizing user experience.

Minimum labour standards enforcement in Australia : caught in the crossfire?

The complex transition from convict to free labour influenced state intervention in the employment relationship, and initiated the first minimum labour standards in Australia in 1828. Since then, two principal sets of tensions have affected the enforcement of such standards: tensions between government and employers, and tensions between the major political parties over industrial and economic issues. This article argues that these tensions have resulted in a sustained legacy affecting minimum labour standards’ enforcement in Australia. The article outlines broad historical developments and contexts of minimum labour standards’ enforcement in Australia since 1828, with more contemporary exploration focusing specifically on enforcement practices and policies in the Australian federal industrial relations jurisdiction. Current enforcement practices are an outcome of this volatile history, and past influences remain strong.

Selection of solar energy for green building using superiority and inferiority multi-criteria ranking (SIR) method

Green energy is one of the key factors, driving down electricity bill and zero carbon emission generating electricity to green building. However, the climate change and environmental policies are accelerating people to use renewable energy instead of coal-fired (convention type) energy for green building that energy is not environmental friendly. Therefore, solar energy is one of the clean energy solving environmental impact and paying less in electricity fee. The method of solar energy is collecting sun from solar array and saves in battery from which provides necessary electricity to whole house with zero carbon emission. However, in the market a lot of solar arrays suppliers, the aims of this paper attempted to use superiority and inferiority multi-criteria ranking (SIR) method with 13 constraints establishing I-flows and S-flows matrices to evaluate four alternatives solar energies and determining which alternative is the best, providing power to sustainable building. Furthermore, SIR is well-known structured approach of multi-criteria decision support tools and gradually used in construction and building. The outcome of this paper significantly gives an indication to user selecting solar energy.

Sustainability criteria for Industrialised Building System (IBS) in Malaysia

As the sustainability awareness rises globally, the construction industry is under increasing pressure to improve efficiency and project delivery. The implementation of Industrialised Building Systems (IBS), for which utility components are built offsite, has the potential of promoting sustainability deliverables. This can be achieved by better control of production environment, minimising construction waste, using efficient building material energy, and stabilising work conditions. As a unique building technology, IBS has not been effectively implemented in Malaysia. Possible reasons may include limited understanding among stakeholders on the IBS potential and its relevance to sustainability. This warrants studies on the sustainability issues of IBS design, construction, operation and maintenance, A framework is being developed through research to assess performance criteria related to sustainability, which should be considered during IBS design and application in the most consistent and systematic way. This paper discusses how these sustainability performance criteria are examined in a continuing research project and the processes conducive to implementing sustainable IBS in Malaysia. Existing tools, indicators and guidelines are reviewed, analysed and grouped according to characteristics and application. The research also hopes to produce guidelines for stakeholders to incorporate sustainability issues and concepts into IBS applications.