523 resultados para power shift


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This paper will provide an overview of a join research initiative being developed by the Queensland University of Technology in conjunction with the Australian Smart Services Cooperative Research Centre in relation to the development and analysis of online communities. The intention of this project is to initially create an exciting and innovative web space around the concept of adventure travel and then to analyse the level of user engagement to uncover possible patterns and processes that could be used in the future development of other virtual online communities. Travel websites are not a new concept and there are many successful examples currently operating and generating profit. The intention of the QUT/Smart Services CRC project is to analyse the site metrics to determine the following: what specific conditions/parameters are required to foster a growing and engaged virtual community; when does the shift occur from external moderation to a more sustainable system of self-moderation within the online community; when do users begin to take ownership of a site and take an invested interested in the content and growth of an online community; and how to retain active contributors and high-impact power users on a long-term basis. With the travel website rapidly approaching release, this paper begins the process of reflection, outlining the process undertaken and the findings so far aggregated whilst also positioning the project within the greater context of current online user participation and user generated content research.

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The availability and use of online counseling approaches has increased rapidly over the last decade. While research has suggested a range of potential affordances and limitations of online counseling modalities, very few studies have offered detailed examinations of how counselors and clients manage asynchronous email counseling exchanges. In this paper we examine email exchanges involving clients and counselors through Kids Helpline, a national Australian counseling service that offers free online, email and telephone counseling for young people up to the age of 25. We employ tools from the traditions of ethnomethodology and conversation analysis to analyze the ways in which counselors from Kids Helpline request that their clients call them, and hence change the modality of their counseling relationship, from email to telephone counseling. This paper shows the counselors’ three multi-layered approaches in these emails as they negotiate the potentially delicate task of requesting and persuading a client to change the trajectory of their counseling relationship from text to talk without placing that relationship in jeopardy.

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The potential of distributed reactive power control to improve the voltage profile of radial distribution feeders has been reported in literature by few authors. However, the multiple inverters injecting or absorbing reactive power across a distribution feeder may introduce control interactions and/or voltage instability. Such controller interactions can be alleviated if the inverters are allowed to operate on voltage droop. First, the paper demonstrates that a linear shallow droop line can maintain the steady state voltage profile close to reference, up to a certain level of loading. Then, impacts of the shallow droop line control on line losses and line power factors are examined. Finally, a piecewise linear droop line which can achieve reduced line losses and close to unity power factor at the feeder source is proposed.

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Electricity has been the major source of power in most railway systems. Reliable, efficient and safe power distribution to the trains is vitally important to the overall quality of railway service. Like any large-scale engineering system, design, operation and planning of traction power systems rely heavily on computer simulation. This paper reviews the major features on modelling and the general practices for traction power system simulation; and introduces the development of the latest simulation approach with discussions on simulation results and practical applications. Remarks will also be given on the future challenges on traction power system simulation.

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The use of grant contracts to deliver community services is now a significant feature of all Australian government administrations. These contracts are the primary instrument governing the provision of such services to citizens and are largely outside the usual parliamentary review mechanisms and constraints. This article examines the extent of the erosion of fundamental constitutional principles facilitated by the use of private contracts, by applying the principles used in scrutiny of delegated legislation to standard form federal and State community service contracts. It reveals extensive executive power which, if the relationship were founded in legislative instruments rather than in private contract, would have to be justified to Parliament at least and possibly not tolerated.

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In this paper, I outline a new approach towards media and diaspora using the concept of the ‘franchise nation’. It is my contention that current theories on migration, media and diaspora with their emphasis on exile, multiple belongings, hybrid identities and their representations are inadequate to the task of explaining the emergence of a new trend in diaspora, home and host nation relationship. This, I suggest, is a recent shift most notable in the attitudes of the Chinese and Indian governments toward their diasporas. From earlier eras where Chinese sojourners were regarded as disloyal and Indians overseas left to fend for themselves, Chinese and Indian migrants are today directly addressed and wooed by their nations of origin. This change is motivated in part by the realisation that diasporic populations are, in fact, resources that can bring significant influence to bear on home nation interests within host nations. Such sway in foreign lands gains greater importance as China and India are, by virtue of their economic rise and prominence on the world stage, subject to ever more intense international scrutiny. Members of these diasporas have willingly responded to these changes by claiming and cultivating pivotal roles for themselves within host nations as spokespersons, informants and representatives, trading on their assumed familiarity with home cultures, language and commerce. As a result, China and India have initiated a number of statecraft strategies in recent years to (re)engage their diasporas. Both nations have identified media as amongst the key instruments of their strategies. New media enhances the ability of all parties—home and host states, institutions and individuals—to participate, interact and reciprocate. While China’s centralised government has utilised the notion of soft power (ruan shili) to describe its practices, India’s efforts are diffused along the lines of nation branding via myriad labels like India Inc. and the Global Indian. To explain this emergent trend, I propose a new framework, franchise nation, defined as a reciprocal relationship between nation and diaspora that is characterised by mutual obligations and benefits. In appropriating this phrase from Stephenson, I liken contemporary statecraft operating in China and India to a business franchising system wherein benefits may be economic or cultural and; those thus connected signal their willingness for mutual exchange and concede a sense of obligation. As such, franchise nation is not concerned with remote, unidirectional interference in home nation affairs a la Anderson’s ‘long-distance nationalism’. Rather, it is a framework that seeks to reflect more closely the dynamism of the relationship between diaspora, home and host nations.

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With examples drawn from media coverage of the War on Terror, the 2003 invasion of Iraq, Hurricane Katrina and the London underground bombings, Cultural Chaos explores the changing relationship between journalism and power in an increasingly globalised news culture. In this new text, Brian McNair examines the processes of cultural, geographic and political dissolution in the post-Cold War era and the rapid evolution of information and communication technologies. He investigates the impact of these trends on domestic and international journalism and on political processes in democratic and authoritarian societies across the world. Written in a lively and accessible style, Cultural Chaos provides students with an overview of the evolution of the sociology of journalism, a critical review of current thinking within media studies and an argument for a revision and renewal of the paradigms that have dominated the field since the early twentieth century. Separate chapters are devoted to new developments such as the rise of the blogosphere and satellite television news and their impact on journalism more generally. Cultural Chaos will be essential reading for all those interested in the emerging globalised news culture of the twenty-first century.

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This paper presents the ultrasonic velocity measurement method which investigates the possible effects of high voltage high frequency pulsed power on cortical bone material elasticity. Before applying a pulsed power signal on a live bone, it is essential to determine the safe parameters of pulsed power applied on bone non-destructively. Therefore, the possible changes in cortical bone material elasticity due to a specified pulsed power excitation have been investigated. A controllable positive buck-boost converter with adjustable output voltage and frequency has been used to generate high voltage pulses (500V magnitude at 10 KHz frequency). To determine bone elasticity, an ultrasonic velocity measurement has been conducted on two groups of control (unexposed to pulse power but in the same environmental condition) and cortical bone samples exposed to pulsed power. Young’s modulus of cortical bone samples have been determined and compared before and after applying the pulsed power signal. After applying the high voltage pulses, no significant variation in elastic property of cortical bone specimens was found compared to the control. The result shows that pulsed power with nominated parameters can be applied on cortical bone tissue without any considerable negative effect on elasticity of bone material.

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Power system dynamic analysis and security assessment are becoming more significant today due to increases in size and complexity from restructuring, emerging new uncertainties, integration of renewable energy sources, distributed generation, and micro grids. Precise modelling of all contributed elements/devices, understanding interactions in detail, and observing hidden dynamics using existing analysis tools/theorems are difficult, and even impossible. In this chapter, the power system is considered as a continuum and the propagated electomechanical waves initiated by faults and other random events are studied to provide a new scheme for stability investigation of a large dimensional system. For this purpose, the measured electrical indices (such as rotor angle and bus voltage) following a fault in different points among the network are used, and the behaviour of the propagated waves through the lines, nodes, and buses is analyzed. The impact of weak transmission links on a progressive electromechanical wave using energy function concept is addressed. It is also emphasized that determining severity of a disturbance/contingency accurately, without considering the related electromechanical waves, hidden dynamics, and their properties is not secure enough. Considering these phenomena takes heavy and time consuming calculation, which is not suitable for online stability assessment problems. However, using a continuum model for a power system reduces the burden of complex calculations

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Legal educators in Australia have increasingly become concerned with the mental health of law students. The apparent risk posed by legal education to a student’s mental health has led to the deployment of a variety of measures to address these problems. By exploring these measures as productive power relations attempting to shape law students, this paper outlines how this government of depression is achieved, and the potential costs of these power relations. It examines one central Australian text offering advice about how students and law student societies can address depression, and argues that doing so not only involves students adopting particular practices of self-government to shape their legal personae, but also relies on an extension of the power relations of legal education. In addition, this paper will link this advice — which privatises the issue of depression, responsibilises individuals and communities, privileges psychological expertise, and seeks to govern ‘at a distance’ — to broader forms of social administration that presently characterise many Western societies. Doing so allows legal educators to reflect on the effects of their attempts to govern depression, and to consider new ways of altering the power relations of legal education.

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Demands for delivering high instantaneous power in a compressed form (pulse shape) have widely increased during recent decades. The flexible shapes with variable pulse specifications offered by pulsed power have made it a practical and effective supply method for an extensive range of applications. In particular, the release of basic subatomic particles (i.e. electron, proton and neutron) in an atom (ionization process) and the synthesizing of molecules to form ions or other molecules are among those reactions that necessitate large amount of instantaneous power. In addition to the decomposition process, there have recently been requests for pulsed power in other areas such as in the combination of molecules (i.e. fusion, material joining), gessoes radiations (i.e. electron beams, laser, and radar), explosions (i.e. concrete recycling), wastewater, exhausted gas, and material surface treatments. These pulses are widely employed in the silent discharge process in all types of materials (including gas, fluid and solid); in some cases, to form the plasma and consequently accelerate the associated process. Due to this fast growing demand for pulsed power in industrial and environmental applications, the exigency of having more efficient and flexible pulse modulators is now receiving greater consideration. Sensitive applications, such as plasma fusion and laser guns also require more precisely produced repetitive pulses with a higher quality. Many research studies are being conducted in different areas that need a flexible pulse modulator to vary pulse features to investigate the influence of these variations on the application. In addition, there is the need to prevent the waste of a considerable amount of energy caused by the arc phenomena that frequently occur after the plasma process. The control over power flow during the supply process is a critical skill that enables the pulse supply to halt the supply process at any stage. Different pulse modulators which utilise different accumulation techniques including Marx Generators (MG), Magnetic Pulse Compressors (MPC), Pulse Forming Networks (PFN) and Multistage Blumlein Lines (MBL) are currently employed to supply a wide range of applications. Gas/Magnetic switching technologies (such as spark gap and hydrogen thyratron) have conventionally been used as switching devices in pulse modulator structures because of their high voltage ratings and considerably low rising times. However, they also suffer from serious drawbacks such as, their low efficiency, reliability and repetition rate, and also their short life span. Being bulky, heavy and expensive are the other disadvantages associated with these devices. Recently developed solid-state switching technology is an appropriate substitution for these switching devices due to the benefits they bring to the pulse supplies. Besides being compact, efficient, reasonable and reliable, and having a long life span, their high frequency switching skill allows repetitive operation of pulsed power supply. The main concerns in using solid-state transistors are the voltage rating and the rising time of available switches that, in some cases, cannot satisfy the application’s requirements. However, there are several power electronics configurations and techniques that make solid-state utilisation feasible for high voltage pulse generation. Therefore, the design and development of novel methods and topologies with higher efficiency and flexibility for pulsed power generators have been considered as the main scope of this research work. This aim is pursued through several innovative proposals that can be classified under the following two principal objectives. • To innovate and develop novel solid-state based topologies for pulsed power generation • To improve available technologies that have the potential to accommodate solid-state technology by revising, reconfiguring and adjusting their structure and control algorithms. The quest to distinguish novel topologies for a proper pulsed power production was begun with a deep and through review of conventional pulse generators and useful power electronics topologies. As a result of this study, it appears that efficiency and flexibility are the most significant demands of plasma applications that have not been met by state-of-the-art methods. Many solid-state based configurations were considered and simulated in order to evaluate their potential to be utilised in the pulsed power area. Parts of this literature review are documented in Chapter 1 of this thesis. Current source topologies demonstrate valuable advantages in supplying the loads with capacitive characteristics such as plasma applications. To investigate the influence of switching transients associated with solid-state devices on rise time of pulses, simulation based studies have been undertaken. A variable current source is considered to pump different current levels to a capacitive load, and it was evident that dissimilar dv/dts are produced at the output. Thereby, transient effects on pulse rising time are denied regarding the evidence acquired from this examination. A detailed report of this study is given in Chapter 6 of this thesis. This study inspired the design of a solid-state based topology that take advantage of both current and voltage sources. A series of switch-resistor-capacitor units at the output splits the produced voltage to lower levels, so it can be shared by the switches. A smart but complicated switching strategy is also designed to discharge the residual energy after each supply cycle. To prevent reverse power flow and to reduce the complexity of the control algorithm in this system, the resistors in common paths of units are substituted with diode rectifiers (switch-diode-capacitor). This modification not only gives the feasibility of stopping the load supply process to the supplier at any stage (and consequently saving energy), but also enables the converter to operate in a two-stroke mode with asymmetrical capacitors. The components’ determination and exchanging energy calculations are accomplished with respect to application specifications and demands. Both topologies were simply modelled and simulation studies have been carried out with the simplified models. Experimental assessments were also executed on implemented hardware and the approaches verified the initial analysis. Reports on details of both converters are thoroughly discussed in Chapters 2 and 3 of the thesis. Conventional MGs have been recently modified to use solid-state transistors (i.e. Insulated gate bipolar transistors) instead of magnetic/gas switching devices. Resistive insulators previously used in their structures are substituted by diode rectifiers to adjust MGs for a proper voltage sharing. However, despite utilizing solid-state technology in MGs configurations, further design and control amendments can still be made to achieve an improved performance with fewer components. Considering a number of charging techniques, resonant phenomenon is adopted in a proposal to charge the capacitors. In addition to charging the capacitors at twice the input voltage, triggering switches at the moment at which the conducted current through switches is zero significantly reduces the switching losses. Another configuration is also introduced in this research for Marx topology based on commutation circuits that use a current source to charge the capacitors. According to this design, diode-capacitor units, each including two Marx stages, are connected in cascade through solid-state devices and aggregate the voltages across the capacitors to produce a high voltage pulse. The polarity of voltage across one capacitor in each unit is reversed in an intermediate mode by connecting the commutation circuit to the capacitor. The insulation of input side from load side is provided in this topology by disconnecting the load from the current source during the supply process. Furthermore, the number of required fast switching devices in both designs is reduced to half of the number used in a conventional MG; they are replaced with slower switches (such as Thyristors) that need simpler driving modules. In addition, the contributing switches in discharging paths are decreased to half; this decrease leads to a reduction in conduction losses. Associated models are simulated, and hardware tests are performed to verify the validity of proposed topologies. Chapters 4, 5 and 7 of the thesis present all relevant analysis and approaches according to these topologies.

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Power relations and small and medium-sized enterprise strategies for capturing value in global production networks: visual effects (VFX) service firms in the Hollywood film industry, Regional Studies. This paper provides insights into the way in which non-lead firms manoeuvre in global value chains in the pursuit of a larger share of revenue and how power relations affect these manoeuvres. It examines the nature of value capture and power relations in the global supply of visual effects (VFX) services and the range of strategies VFX firms adopt to capture higher value in the global value chain. The analysis is based on a total of thirty-six interviews with informants in the industry in Australia, the United Kingdom and Canada, and a database of VFX credits for 3323 visual products for 640 VFX firms.

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It is almost a truism that persons who occupy formal bureaucratic positions in schools may not actually be leaders if they were not role incumbents in a bureaucracy. It is also clear from studies of grassroots leaders that without the qualities of skills of leadership no one would follow them because they have no formal, hierarchical role upon which others were dependent to them. One of the reasons for re-examining the nature of grassroots leaders is to attempt to recapture those tactics or strategies which might be reconceptualized and utilized within more formal settings so that role dependent leadership becomes more effectual and trustworthy than one that is totally dependent on role authority. This reasoning is especially a critical need if there is a desire to work towards more democratic and collaborative working arrangements between leaders and followers, and where more flexible and dynamic relationships promise higher levels of commitment and productivity. Hecksher (1994) speaks of such a reconceptualization as part of a shift from an emphasis on power to one centered on influence. This paper examines the nature of leadership before it was subjected to positivistic science and later behavioural studies. This move follows the advice of Heilbrunn (1996) who trenchantly observed that for leadership studies to grow as a discipline, “it will have to cast a wider net” (p.11). Willis et. Al. (2008) make a similar point when they lament that social scientist have forced favoured understanding bureaucracies rather than grassroots community organizations, yet much can be gained by being aware of the tactics and strategies used by grassroots leaders who depend on influence as opposed to power. This paper, then, aims to do this by posing a tentative model of grassroots leadership and then considering how this model might inform and be used by those responsible for developing school leaders.

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The authors examine Moylan v Rickard and how the case illustrates the effectiveness of the Powers of Attorney Act 1998 (Qld) to provide remedies and other possible avenues of redress