305 resultados para common sense


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This chapter addresses the question, how can the common law concept of charity law be modernised? There are difficulties with the present jurisprudential conception. The focus of the chapter is not on those difficulties, however, but rather on the development of an alternative architecture for common law jurisprudence. The conclusion to which the chapter comes is that charity law can be modernised by a series of steps to include all civil society organisations. It is possible if the ‘technical’ definition of charitable purpose is abandoned in favour of a contemporary, not technical concept of charitiable purpose. This conclusion is reached by proposing a framework, developed from the common law concept of charities, that reconciles into a cohesive jurisprudential architecture all of the laws applying to civil society organisations, not just charities. In this section, first the argument is contextualised in an idea of society and located in a gap in legal theory. An analogy is then offered to introduce the problems in the legal theory applying, not just to charities, but more broadly to civil society organisations. The substantive challenge of mapping an alternative jurisprudence is then taken in steps. The final substantive section conceptualises the changes inherent in a move beyond charities to a jurisprudence centred on civil society organisations and how this would bring legal theory into line with sectoral analysis in other disciplines.

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AC motors are largely used in a wide range of modern systems, from household appliances to automated industry applications such as: ventilations systems, fans, pumps, conveyors and machine tool drives. Inverters are widely used in industrial and commercial applications due to the growing need for speed control in ASD systems. Fast switching transients and the common mode voltage, in interaction with parasitic capacitive couplings, may cause many unwanted problems in the ASD applications. These include shaft voltage and leakage currents. One of the inherent characteristics of Pulse Width Modulation (PWM) techniques is the generation of the common mode voltage, which is defined as the voltage between the electrical neutral of the inverter output and the ground. Shaft voltage can cause bearing currents when it exceeds the amount of breakdown voltage level of the thin lubricant film between the inner and outer rings of the bearing. This phenomenon is the main reason for early bearing failures. A rapid development in power switches technology has lead to a drastic decrement of switching rise and fall times. Because there is considerable capacitance between the stator windings and the frame, there can be a significant capacitive current (ground current escaping to earth through stray capacitors inside a motor) if the common mode voltage has high frequency components. This current leads to noises and Electromagnetic Interferences (EMI) issues in motor drive systems. These problems have been dealt with using a variety of methods which have been reported in the literature. However, cost and maintenance issues have prevented these methods from being widely accepted. Extra cost or rating of the inverter switches is usually the price to pay for such approaches. Thus, the determination of cost-effective techniques for shaft and common mode voltage reduction in ASD systems, with the focus on the first step of the design process, is the targeted scope of this thesis. An introduction to this research – including a description of the research problem, the literature review and an account of the research progress linking the research papers – is presented in Chapter 1. Electrical power generation from renewable energy sources, such as wind energy systems, has become a crucial issue because of environmental problems and a predicted future shortage of traditional energy sources. Thus, Chapter 2 focuses on the shaft voltage analysis of stator-fed induction generators (IG) and Doubly Fed Induction Generators DFIGs in wind turbine applications. This shaft voltage analysis includes: topologies, high frequency modelling, calculation and mitigation techniques. A back-to-back AC-DC-AC converter is investigated in terms of shaft voltage generation in a DFIG. Different topologies of LC filter placement are analysed in an effort to eliminate the shaft voltage. Different capacitive couplings exist in the motor/generator structure and any change in design parameters affects the capacitive couplings. Thus, an appropriate design for AC motors should lead to the smallest possible shaft voltage. Calculation of the shaft voltage based on different capacitive couplings, and an investigation of the effects of different design parameters are discussed in Chapter 3. This is achieved through 2-D and 3-D finite element simulation and experimental analysis. End-winding parameters of the motor are also effective factors in the calculation of the shaft voltage and have not been taken into account in previous reported studies. Calculation of the end-winding capacitances is rather complex because of the diversity of end winding shapes and the complexity of their geometry. A comprehensive analysis of these capacitances has been carried out with 3-D finite element simulations and experimental studies to determine their effective design parameters. These are documented in Chapter 4. Results of this analysis show that, by choosing appropriate design parameters, it is possible to decrease the shaft voltage and resultant bearing current in the primary stage of generator/motor design without using any additional active and passive filter-based techniques. The common mode voltage is defined by a switching pattern and, by using the appropriate pattern; the common mode voltage level can be controlled. Therefore, any PWM pattern which eliminates or minimizes the common mode voltage will be an effective shaft voltage reduction technique. Thus, common mode voltage reduction of a three-phase AC motor supplied with a single-phase diode rectifier is the focus of Chapter 5. The proposed strategy is mainly based on proper utilization of the zero vectors. Multilevel inverters are also used in ASD systems which have more voltage levels and switching states, and can provide more possibilities to reduce common mode voltage. A description of common mode voltage of multilevel inverters is investigated in Chapter 6. Chapter 7 investigates the elimination techniques of the shaft voltage in a DFIG based on the methods presented in the literature by the use of simulation results. However, it could be shown that every solution to reduce the shaft voltage in DFIG systems has its own characteristics, and these have to be taken into account in determining the most effective strategy. Calculation of the capacitive coupling and electric fields between the outer and inner races and the balls at different motor speeds in symmetrical and asymmetrical shaft and balls positions is discussed in Chapter 8. The analysis is carried out using finite element simulations to determine the conditions which will increase the probability of high rates of bearing failure due to current discharges through the balls and races.

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Communications media have been central to globalizing processes in modern societies. As technological forms, communication media have long extended the transmission of messages across space in ways that challenge the socio-cultural dimensions of the nation-state and national cultures, and the global communications infrastructure that has developed rapidly since the 1980s has further promoted global information flows and cross-border commercial activity. As institutional and organisational forms through which information and content is produced and distributed, media corporations have been at the forefront of international expansion of their market reach and the development of new sites of production and distribution, and media industries are highly dynamic on a global scale. Finally, as cultural forms, or providers of the informational and symbolic content that is received and used by consumers/audiences/users, global media constitute a core means through which people make sense of events in distant places, and the information and images that they carry are central to the existence of common systems of meaning and understanding across nations, regions and cultures.

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Common mode voltage generated by a power converter in combination with parasitic capacitive couplings is a potential source of shaft voltage in an AC motor drive system. In this paper, a three-phase motor drive system supplied with a single-phase AC-DC diode rectifier is investigated in order to reduce shaft voltage in a three-phase AC motor drive system. In this topology, the common mode voltage generated by the inverter is influenced by the AC-DC diode rectifier because the placement of the neutral point is changing in different rectifier circuit states. A pulse width modulation technique is presented by a proper placement of the zero vectors to reduce the common mode voltage level, which leads to a cost effective shaft voltage reduction technique without load current distortion, while keeping the switching frequency constant. Analysis and simulations have been presented to investigate the proposed method.

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The purpose of this book is to show why we should be concerned about virtual communities for people with physical, or more particularly mobility, impairments. The well-being model through a virtual community introduced here goes towards advancing the work begun by others, by adding for example a socio-political component. The model presented here provides practical insights into how strategic community investment can support people with disabilities and their families. Virtual communities are about engagement, quality of life and support, not just about information. The role of information technology in building and raising community capacity and social capital in socially and economically disadvantaged communities is also examined. Practical insights are offered into community support for people with chronic illness.

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This paper describes effective ways secondary school leaders can enact curriculum policy, particularly assessment practices, to support learning for students with disabilities in mainstream schools. Assessment for learning (AfL) as a pedagogic practice, has gained recent importance through inclusion in curriculum policy in Queensland, Australia. AfL is the frequent assessment of student progress that identifies learning needs and informs future teaching and learning. Assessment of student progress of the standards based curriculum has provided challenges for schools attempting to meet the needs of “all” learners. This paper highlights findings of a small case study to model successful leadership practices used in an inclusive secondary school to improve achievement of students with disabilities through assessment. Successful leadership practices that can be generalized to improve achievement of all learners include making sense of policy for staff; developing staff common and shared beliefs and actions; organizing professional learning opportunities and arranging collaborative curriculum planning and co-teaching.

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Background Concern about skin cancer is a common reason for people from predominantly fair-skinned populations to present to primary care doctors. Objectives To examine the frequency and body-site distribution of malignant, pre-malignant and benign pigmented skin lesions excised in primary care. Methods This prospective study conducted in Queensland, Australia, included 154 primary care doctors. For all excised or biopsied lesions, doctors recorded the patient's age and sex, body site, level of patient pressure to excise, and the clinical diagnosis. Histological confirmation was obtained through pathology laboratories. Results Of 9650 skin lesions, 57·7% were excised in males and 75·0% excised in patients ≥50years. The most common diagnoses were basal cell carcinoma (BCC) (35·1%) and squamous cell carcinoma (SCC) (19·7%). Compared with the whole body, the highest densities for SCC, BCC and actinic keratoses were observed on chronically sun-exposed areas of the body including the face in males and females, the scalp and ears in males, and the hands in females. The density of BCC was also high on intermittently or rarely exposed body sites. Females, younger patients and patients with melanocytic naevi were significantly more likely to exert moderate/high levels of pressure on the doctor to excise. Conclusions More than half the excised lesions were skin cancer, which mostly occurred on the more chronically sun-exposed areas of the body. Information on the type and body-site distribution of skin lesions can aid in the diagnosis and planned management of skin cancer and other skin lesions commonly presented in primary care.

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Identifying, modelling and documenting business processes usually requires the collaboration of many stakeholders that may be spread across companies in inter-organizational business settings. While there are many process modelling tools available, the support they provide for remote collaboration is still limited. This demonstration showcases a novel prototype application that implements collaborative virtual environment and augmented reality technologies to improve remote collaborative process modelling, with an aim to assisting common collaboration tasks by providing an increased sense of immersion in an intuitive shared work and task space. Our tool is easily deployed using open source software, and commodity hardware, and is expected to assist with saving money on travel costs for large scale process modelling projects covering national and international centres within an enterprise.

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This study investigates the influence of the built environment upon residents' sense of familiarity, concept of self and thus, their facilitation of place through the theory of "The Bondage of Imposed Visual Discourse". Simone de Beauvoir's theory "The Bondage of Feminine Elegance" provides the conceptual understanding of the visual discourse between the physicality of clothing and the wearer's personal identity. This fashion theory is transposed to explore the influence of the built environment's physicality upon aged care residents' personal identity. This paper presents findings from a study of professionals' opinions in reference to the built environment of permanent residential aged care for the 'oldest-old' of Australia. The researcher conducted qualitative interviews with four participants: an architect, occupational therapist, nursing home facility manager and an aged care lobbyist in the South-East Queensland. This study is structured towards proposing "place-focused" qualitative design principles to encourage residents' sense of place through the built environment. These proposed principles are addressed with reference to existing Standards and Principles outlined by the Australian Government.

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Short fiction