613 resultados para Electric motor industry


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Management and staff of the spatial science program at QUT. Student numbers discussion, Alumni News, Staff and Laboratories moving, Work Integrated Learning in 2010.

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In this paper, several aspects of high frequency related issues of modern AC motor drive systems, such as common mode voltage, shaft voltage and resultant bearing current and leakage currents, have been discussed. Conducted emission is a major problem in modern motor drives that produce undesirable effects on electronic devices. In modern power electronic systems, increasing power density and decreasing cost and size of system are market requirements. Switching losses, harmonics and EMI are the key factors which should be considered at the beginning stage of a design to optimise a drive system.

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In this thesis, a new technique has been developed for determining the composition of a collection of loads including induction motors. The application would be to provide a representation of the dynamic electrical load of Brisbane so that the ability of the power system to survive a given fault can be predicted. Most of the work on load modelling to date has been on post disturbance analysis, not on continuous on-line models for loads. The post disturbance methods are unsuitable for load modelling where the aim is to determine the control action or a safety margin for a specific disturbance. This thesis is based on on-line load models. Dr. Tania Parveen considers 10 induction motors with different power ratings, inertia and torque damping constants to validate the approach, and their composite models are developed with different percentage contributions for each motor. This thesis also shows how measurements of a composite load respond to normal power system variations and this information can be used to continuously decompose the load continuously and to characterize regarding the load into different sizes and amounts of motor loads.

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Rodenticide use in agriculture can lead to the secondary poisoning of avian predators. Currently the Australian sugarcane industry has two rodenticides, Racumin® and Rattoff®, available for in-crop use but, like many agricultural industries, it lacks an ecologically-based method of determining the potential secondary poisoning risk the use of these rodenticides poses to avian predators. The material presented in this thesis addresses this by: a. determining where predator/prey interactions take place in sugar producing districts; b. quantifying the amount of rodenticide available to avian predators and the probability of encounter; and c. developing a stochastic model that allows secondary poisoning risk under various rodenticide application scenarios to be investigated. Results demonstrate that predator/prey interactions are highly constrained by environmental structure. Rodents used crops that provided high levels of canopy cover and therefore predator protection and poorly utilised open canopy areas. In contrast, raptors over-utilised areas with low canopy cover and low rodent densities, but which provided high accessibility to prey. Given this pattern of habitat use, and that industry baiting protocols preclude rodenticide application in open canopy crops, these results indicate that secondary poisoning can only occur if poisoned rodents leave closed canopy crops and become available for predation in open canopy areas. Results further demonstrate that after in-crop rodenticide application, only a small proportion of rodents available in open areas are poisoned and that these rodents carry low levels of toxicant. Coupled with the low level of rodenticide use in the sugar industry, the high toxic threshold raptors have to these toxicants and the low probability of encountering poisoned rodents, results indicate that the risk of secondary poisoning events occurring is minimal. A stochastic model was developed to investigate the effect of manipulating factors that might influence secondary poisoning hazard in a sugarcane agro-ecosystem. These simulations further suggest that in all but extreme scenarios, the risk of secondary poisoning is also minimal. Collectively, these studies demonstrate that secondary poisoning of avian predators associated with the use of the currently available rodenticides in Australian sugar producing districts is minimal. Further, the ecologically-based method of assessing secondary poisoning risk developed in this thesis has broader applications in other agricultural systems where rodenticide use may pose risks to avian predators.

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In the late 1990s New Zealand fashion gained some international recognition for its dark edginess and intellectual connection due to its colonial past (Molloy, 2004). In the years since, this momentum seems to have dissipated as local fashion companies have followed a global trend towards inexpensive off shore manufacturing. The transfer of the making of garments to overseas workers appears to have resulted in a local fashion scene where many garments look the same in style, colour, cut and fit. The excitement of the past, where the majority of fashion designers established their own individuality through the cut and shape of the garments that they produced, may have been inadvertently lost. Consequently a sustainable New Zealand fashion and manufacturing industry, with design integrity, seems further out of reach. The first question posed by this research project is, ‘can the design and manufacture of a fashion garment, bearing in mind certain economic and practical restrictions at its inception, result in the development of a distinctive ‘look’ or ‘handwriting’?’ Second, through development of a collection of prototypes, can potential garments be created to be sustainably manufactured in New Zealand?

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As most of people know that all of mass media are state-owned in China, television stations are not exceptional to belong to the enormous state-owned system. But to date, with the economic reform in the broadcasting system and China entering into WTO, the television industry has increased greatly and the television market has matured with more and more competition. The players in China’s television industry have changed from the monologue of TV stations to multi roles of TV stations, production companies and overseas television companies, although TV stations are still the majority of China’s TV market. Especially, private television production companies are becoming more and more active in this market. In this paper, I will describe the development process and challenges of this group in China and ask whether the emergence of this group means for the whole China’s TV industry?

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Since the early 1980s, researchers and practitioners in the organisational and management fields have presumed a link between organisational, or corporate, culture and organisational performance. Whilst many believe this exists, other authors have been critical of the validity of such studies. Part of this doubt stems from a reliance on measures of organisational performance that are based purely on financial measures of business growth. Using the construction industry as the subject of his research, Vaughan Coffey traces the development of the literature on organisational culture and business effectiveness and investigates the culture–performance link using a new and highly objective measure of company performance and an evaluation of organisational culture, which is largely behaviourally-based. Providing a theoretical contribution to the field, this work shows that various cultural traits appear to be closely linked to objectively measured organisational effectiveness. This book will be valuable to professionals and researchers in the fields of management and public policy. It indicates directions for construction companies to develop and change, and in doing so strengthen their chances of remaining strong when opportunities for work might deplete and only the most successful companies will be able to survive.---- Selected Contents: 1. An Introduction to Organizations, Culture, Performance and Construction 2. Organizations, Culture and Climate 3. Organizational Culture Studies 4. Measuring Organizational Performance and Effectiveness 5. Organizational Culture and Effectiveness – The Link Between Them 6. Research on the Relationship between Organizational Culture and Performance in Hong Kong Construction Companies 7. The Hong Kong Experiment – Presentation of Demographic Data, Overall Results and some Descriptive and Qualitative Analysis 8. Detailed Statistical Analysis of the Docs and Pass Data in Relation to the Major Research Questions 9. Four Hong Kong Construction Mini-Case Studies 10. Conclusions and Future Research Directions

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The main contribution of this paper is decomposition/separation of the compositie induction motors load from measurement at a system bus. In power system transmission buses load is represented by static and dynamic loads. The induction motor is considered as the main dynamic loads and in the practice for major transmission buses there will be many and various induction motors contributing. Particularly at an industrial bus most of the load is dynamic types. Rather than traing to extract models of many machines this paper seeks to identify three groups of induction motors to represent the dynamic loads. Three groups of induction motors used to characterize the load. These are the small groups (4kw to 11kw), the medium groups (15kw to 180kw) and the large groups (above 630kw). At first these groups with different percentage contribution of each group is composite. After that from the composite models, each motor percentage contribution is decomposed by using the least square algorithms. In power system commercial and the residential buses static loads percentage is higher than the dynamic loads percentage. To apply this theory to other types of buses such as residential and commerical it is good practice to represent the total load as a combination of composite motor loads, constant impedence loads and constant power loads. To validate the theory, the 24hrs of Sydney West data is decomposed according to the three groups of motor models.

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Background: In order to design appropriate environments for performance and learning of movement skills, physical educators need a sound theoretical model of the learner and of processes of learning. In physical education, this type of modelling informs the organization of learning environments and effective and efficient use of practice time. An emerging theoretical framework in motor learning, relevant to physical education, advocates a constraints-led perspective for acquisition of movement skills and game play knowledge. This framework shows how physical educators could use task, performer and environmental constraints to channel acquisition of movement skills and decision making behaviours in learners. From this viewpoint, learners generate specific movement solutions to satisfy the unique combination of constraints imposed on them, a process which can be harnessed during physical education lessons. Purpose: In this paper the aim is to provide an overview of the motor learning approach emanating from the constraints-led perspective, and examine how it can substantiate a platform for a new pedagogical framework in physical education: nonlinear pedagogy. We aim to demonstrate that it is only through theoretically valid and objective empirical work of an applied nature that a conceptually sound nonlinear pedagogy model can continue to evolve and support research in physical education. We present some important implications for designing practices in games lessons, showing how a constraints-led perspective on motor learning could assist physical educators in understanding how to structure learning experiences for learners at different stages, with specific focus on understanding the design of games teaching programmes in physical education, using exemplars from Rugby Union and Cricket. Findings: Research evidence from recent studies examining movement models demonstrates that physical education teachers need a strong understanding of sport performance so that task constraints can be manipulated so that information-movement couplings are maintained in a learning environment that is representative of real performance situations. Physical educators should also understand that movement variability may not necessarily be detrimental to learning and could be an important phenomenon prior to the acquisition of a stable and functional movement pattern. We highlight how the nonlinear pedagogical approach is student-centred and empowers individuals to become active learners via a more hands-off approach to learning. Summary: A constraints-based perspective has the potential to provide physical educators with a framework for understanding how performer, task and environmental constraints shape each individual‟s physical education. Understanding the underlying neurobiological processes present in a constraints-led perspective to skill acquisition and game play can raise awareness of physical educators that teaching is a dynamic 'art' interwoven with the 'science' of motor learning theories.

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Building project management requires effective coordination and collaboration between multiple project members. It can be achieved through real time communication flow between all. In present scenario, it can be achieved through adoption of Information and Communication Technologies (ICT). Construction industry primarily comprises small and medium enterprises (SMEs). Also, ICT adoption has been slow in the industry.---------- Research is required to assess the factors that affect ICT adoption at the three levels of industry, organization and people, with focus on SMEs. This paper discusses a component of the research undertaken to study these factors and issues in the context of Indian construction industry. A questionnaire survey was conducted and through quantitative data analysis the extent of adoption of formal Project Management processes, ICT adoption for these processes and factors including perception based factors affecting ICT adoption were studied. Results of data analysis includes identification of issues that require action at the three study levels.---------- The results can be generalized for other countries with due considerations, specifically for countries where the construction industry is similar to Indian construction industry in terms of working methodologies or for large countries.

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Research examining post-trauma pathology indicates negative outcomes can differ as a function of the type of trauma experienced. Such research has yet to be published when looking at positive post-trauma changes. Ninety-Four survivors of trauma, forming three groups, completed the Posttraumatic Growth Inventory (PTGI) and Impact of Events Scale-Revised (IES-R). Groups comprised survivors of i) sexual abuse ii) motor vehicle accidents iii) bereavement. Results indicted differences in growth between the groups with the bereaved reporting higher levels of growth than other survivors and sexual abuse survivors demonstrated higher levels of PTSD symptoms than the other groups. However, this did not preclude sexual abuse survivors from also reporting moderate levels of growth. Results are discussed with relation to fostering growth through clinical practice.

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Several brain imaging studies have assumed that response conflict is present in Stroop tasks. However, this has not been demonstrated directly. We examined the time-course of stimulus and response conflict resolution in a numerical Stroop task by combining single-trial electro-myography (EMG) and event-related brain potentials (ERP). EMG enabled the direct tracking of response conflict and the peak latency of the P300 ERP wave was used to index stimulus conflict. In correctly responded trials of the incongruent condition EMG detected robust incorrect response hand activation which appeared consistently in single trials. In 50–80% of the trials correct and incorrect response hand activation coincided temporally, while in 20–50% of the trials incorrect hand activation preceded correct hand activation. EMG data provides robust direct evidence for response conflict. However, congruency effects also appeared in the peak latency of the P300 wave which suggests that stimulus conflict also played a role in the Stroop paradigm. Findings are explained by the continuous flow model of information processing: Partially processed task-irrelevant stimulus information can result in stimulus conflict and can prepare incorrect response activity. A robust congruency effect appeared in the amplitude of incongruent vs. congruent ERPs between 330–400 ms, this effect may be related to the activity of the anterior cingulate cortex.

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Computer systems have become commonplace in most SMEs and technology is increasingly becoming a part of doing business. In recent years, the Internet has become readily available to businesses; consequently there has been growing pressure on SMEs to take up e-commerce. However, e-commerce is perceived by many as being unproven in terms of business benefit. This research aims to determine what, if any, benefits are derived from assimilating e-commerce technologies into SME business processes. This paper presents three in-depth case studies from the Real Estate industry in a regional setting. Overall, findings were positive and identified the following experiences: enhanced business efficiencies, cost benefits, improved customer interactions and increased business return on investment.

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This study addresses calls in the literature for the external validation of Western-based marketing concepts and theory in the East. Using DINESERV, the relationships between service quality, overall service quality perceptions, customer satisfaction, and repurchase intentions in the Malaysian fast food industry are examined. A questionnaire was administered to Malaysian fast food consumers at a large university, resulting in findings that support the five-dimensional nature of DINESERV and three of four proposed hypotheses. This study contributes to knowledge of service quality in developing countries and is the first to examine DINESERV in the Malaysian fast food industry.

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A new cold-formed steel beam, known as the LiteSteel Beam (LSB), has the potential to transform the low-rise building industry. The new beam is effectively a channel section with two rectangular hollow flanges and a slender web, and is manufactured using a simultaneous cold-forming and electric resistance welding process. Research into the flexural behaviour of single LSB members showed that the LSBs are susceptible to lateral distortional buckling effects and their moment capacities are significantly reduced for intermediate spans. Build-up LSB sections are expected to improve their flexural capacity and to enhance their applications. They are also likely to mitigate the detrimental effects of lateral distortional buckling observed with single LSB members of intermediate spans. However, the behaviour of build up beams is not well understood. Currently available design rules were found to be inadequate to predict the member moment capacities of back to back LSBs. Therefore a research project based on both experimental and numerical studies was undertaken to investigate the flexural behaviour of back to back LSBs with various longitudinal connection spacings under a uniform moment. New design rules were developed using the moment capacity data obtained using finite element analyses and experimental tests. This paper presents the details of the development of design rules for the back to back LSB sections.