964 resultados para Global asymptotic stability


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In this paper, teachers’ enactment of assessment policy within demands for accountability and consistency of teacher judgements is considered. Evidence is drawn from a qualitative study involving 50 middle school teachers from Queensland, Australia, who participated in online social moderation meetings with teachers located in dispersed areas around the state. The study presents how travelling policy is embedded in local histories and cultures, in particular within systems of accountability; and the different layers of what may be considered ‘local’. The paper examines the intersections of travelling and embedded policy, and global and local contexts as these are enacted through online moderation meetings.

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Current governance challenges facing the global games industry are heavily dominated by online games. Whilst much academic and industry attention has been afforded to Virtual Worlds, the more pressing contemporary challenges may arise in casual games, especially when found on social networks. As authorities are faced with an increasing volume of disputes between participants and platform operators, the likelihood of external regulation increases, and the role that such regulation would have on the industry – both internationally and within specific regions – is unclear. Kelly (2010) argues that “when you strip away the graphics of these [social] games, what you are left with is simply a button [...] You push it and then the game returns a value of either Win or Lose”. He notes that while “every game developer wants their game to be played, preferably addictively, because it’s so awesome”, these mechanics lead not to “addiction of engagement through awesomeness” but “the addiction of compulsiveness”, surmising that “the reality is that they’ve actually sort-of kind-of half-intentionally built a virtual slot machine industry”. If such core elements of social game design are questioned, this gives cause to question the real-money options to circumvent them. With players able to purchase virtual currency and speed the completion of tasks, the money invested by the 20% purchasing in-game benefits (Zainwinger, 2012) may well be the result of compulsion. The decision by the Japanese Consumer Affairs agency to investigate the ‘Kompu Gacha’ mechanic (in which players are rewarded for completing a set of items obtained through purchasing virtual goods such as mystery boxes), and the resultant verdict that such mechanics should be regulated through gambling legislation, demonstrates that politicians are beginning to look at the mechanics deployed in these environments. Purewal (2012) states that “there’s a reasonable argument that complete gacha would be regulated under gambling law under at least some (if not most) Western jurisdictions”. This paper explores the governance challenged within these games and platforms, their role in the global industry, and current practice amongst developers in the Australian and United States to address such challenges.

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This paper focuses on Australian development firms in the console and mobile games industry in order to understand how small firms in a geographically remote and marginal position in the global industry are able to relate to global firms and capture revenue share. This paper shows that, while technological change in the games industry has resulted in the emergence of new industry segments based on transactional rather than relational forms of economic coordination, in which we might therefore expect less asymmetrical power relations, lead firms retain a position of power in the global games entertainment industry relative to remote developers. This has been possible because lead firms in the emerging mobile devices market have developed and sustained bottlenecks in their segment of the industry through platform competition and the development of an intensely competitive ecosystem of developers. Our research shows the critical role of platform competition and bottlenecks in influencing power asymmetries within global markets.

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With the ever-increasing penetration level of wind power, the impacts of wind power on the power system are becoming more and more significant. Hence, it is necessary to systematically examine its impacts on the small signal stability and transient stability in order to find out countermeasures. As such, a comprehensive study is carried out to compare the dynamic performances of power system respectively with three widely-used power generators. First, the dynamic models are described for three types of wind power generators, i. e. the squirrel cage induction generator (SCIG), doubly fed induction generator (DFIG) and permanent magnet generator (PMG). Then, the impacts of these wind power generators on the small signal stability and transient stability are compared with that of a substituted synchronous generator (SG) in the WSCC three-machine nine-bus system by the eigenvalue analysis and dynamic time-domain simulations. Simulation results show that the impacts of different wind power generators are different under small and large disturbances.

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Knowledge-based development has become a new urban policy approach for the competitive cities of the global knowledge economy era. For those cities seeking a knowledge-based development, benchmarking is an essential prerequisite for informed and strategic vision and policy making to achieve a prosperous development. Nevertheless, benchmarked knowledge-based development performance analysis of global and emerging knowledge cities is an understudied area. This paper aims to contribute to the field by introducing the methodology of a novel performance assessment model—that is the Knowledge-Based Urban Development Assessment Model—and providing lessons from the application of the model in an international knowledge city performance analysis study. The assessment model puts renowned global and emerging knowledge cities—that are Birmingham, Boston, Brisbane, Helsinki, Istanbul, Manchester, Melbourne, San Francisco, Sydney, Toronto, and Vancouver—under the knowledge-based development microscope. The results of the analysis provide internationally benchmarked snapshot of the degree of achievements in various knowledge-based urban development performance areas of the investigated knowledge cities, and reveals insightful lessons on scrutinizing the global perspectives on knowledge-based development of cities.

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In this paper, a model-predictive control (MPC) method is detailed for the control of nonlinear systems with stability considerations. It will be assumed that the plant is described by a local input/output ARX-type model, with the control potentially included in the premise variables, which enables the control of systems that are nonlinear in both the state and control input. Additionally, for the case of set point regulation, a suboptimal controller is derived which has the dual purpose of ensuring stability and enabling finite-iteration termination of the iterative procedure used to solve the nonlinear optimization problem that is used to determine the control signal.

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Genomic instability underlies the transformation of host cells toward malignancy, promotes development of invasion and metastasis and shapes the response of established cancer to treatment. In this review, we discuss recent advances in our understanding of genomic stability in squamous cell carcinoma of the head and neck (HNSCC), with an emphasis on DNA repair pathways. HNSCC is characterized by distinct profiles in genome stability between similarly staged cancers that are reflected in risk, treatment response and outcomes. Defective DNA repair generates chromosomal derangement that can cause subsequent alterations in gene expression, and is a hallmark of progression toward carcinoma. Variable functionality of an increasing spectrum of repair gene polymorphisms is associated with increased cancer risk, while aetiological factors such as human papillomavirus, tobacco and alcohol induce significantly different behaviour in induced malignancy, underpinned by differences in genomic stability. Targeted inhibition of signalling receptors has proven to be a clinically-validated therapy, and protein expression of other DNA repair and signalling molecules associated with cancer behaviour could potentially provide a more refined clinical model for prognosis and treatment prediction. Development and expansion of current genomic stability models is furthering our understanding of HNSCC pathophysiology and uncovering new, promising treatment strategies. © 2013 Glenn Jenkins et al.

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Early diagnosis and the ability to predict the most relevant treatment option for individuals is essential to improve clinical outcomes for non-small cell lung cancer (NSCLC) patients. Adenocarcinoma (ADC), a subtype of NSCLC, is the single biggest cancer killer and therefore an urgent need to identify minimally invasive biomarkers to enable early diagnosis. Recent studies, by ourselves and others, indicate that circulating miRNA s have potential as biomarkers. Here we applied global profiling approaches in serum from patients with ADC of the lung to explore if miRNA s have potential as diagnostic biomarkers. This study involved RNA isolation from 80 sera specimens including those from ADC patients (equal numbers of stages 1, 2, 3, and 4) and age- and gender-matched controls (n = 40 each). Six hundred and sixty-seven miRNA s were co-analyzed in these specimens using TaqMan low density arrays and qPCR validation using individual miRNA s. Overall, approximately 390 and 370 miRNA s were detected in ADC and control sera, respectively. A group of 6 miRNA s, miR-30c-1* (AU C = 0.74; P < 0.002), miR-616(AU C = 0.71; P = 0.001), miR-146b-3p (AU C = 0.82; P < 0.0001), miR-566 (AU C = 0.80; P < 0.0001), miR-550 (AU C = 0.72; P = 0.0006), and miR-939 (AU C = 0.82; P < 0.0001) was found to be present at substantially higher levels in ADC compared with control sera. Conversely, miR-339-5p and miR-656 were detected at substantially lower levels in ADC sera (co-analysis resulting in AU C = 0.6; P = 0.02). Differences in miRNA profile identified support circulating miRNA s having potential as diagnostic biomarkers for ADC. More extensive studies of ADC and control serum specimens are warranted to independently validate the potential clinical relevance of these miRNA s as minimally invasive biomarkers for ADC.

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Purpose To investigate the differences between and variations across time in corneal topography and ocular wavefront aberrations in young Singaporean myopes and emmetropes. Methods We used a videokeratoscope and wavefront sensor to measure the ocular surface topography and wavefront aberrations of the total eye optics in the morning, mid-day and late afternoon on two separate days. Topography data were used to derive the corneal surface wavefront aberrations. Both the corneal and total wavefronts were analysed up to the 4th radial order of the Zernike polynomial expansion, and were centred on the entrance pupil (5 mm). The participants included 12 young progressing myopes, 13 young stable myopes and 15 young age-matched emmetropes. Results For all subjects considered together there were significant changes in some of the aberrations terms across the day, such as spherical aberration ( ) and vertical coma ( ) (repeated measures ANOVA, p<0.05). The magnitude of positive spherical aberration ( ) was significantly lower in the progressing myope group than that of the stable myopes (p=0.04) and emmetrope group (p=0.02). There were also significant interactions between refractive group and time of day for with/against-the-rule astigmatism ( ). Significantly lower 4th order RMS of ocular wavefront aberrations were found in the progressing myope group compared with the stable myopes and emmetropes (p<0.01). Conclusions These differences and variations in the corneal and total aberrations may have significance for our understanding of refractive error development and for clinical applications requiring accurate wavefront measurements.

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Terrorists usually target high occupancy iconic and public buildings using vehicle borne incendiary devices in order to claim a maximum number of lives and cause extensive damage to public property. While initial casualties are due to direct shock by the explosion, collapse of structural elements may extensively increase the total figure. Most of these buildings have been or are built without consideration of their vulnerability to such events. Therefore, the vulnerability and residual capacity assessment of buildings to deliberately exploded bombs is important to provide mitigation strategies to protect the buildings' occupants and the property. Explosive loads and their effects on a building have therefore attracted significant attention in the recent past. Comprehensive and economical design strategies must be developed for future construction. This research investigates the response and damage of reinforced concrete (RC) framed buildings together with their load bearing key structural components to a near field blast event. Finite element method (FEM) based analysis was used to investigate the structural framing system and components for global stability, followed by a rigorous analysis of key structural components for damage evaluation using the codes SAP2000 and LS DYNA respectively. The research involved four important areas in structural engineering. They are blast load determination, numerical modelling with FEM techniques, material performance under high strain rate and non-linear dynamic structural analysis. The response and damage of a RC framed building for different blast load scenarios were investigated. The blast influence region for a two dimensional RC frame was investigated for different load conditions and identified the critical region for each loading case. Two types of design methods are recommended for RC columns to provide superior residual capacities. They are RC columns detailing with multi-layer steel reinforcement cages and a composite columns including a central structural steel core. These are to provide post blast gravity load resisting capacity compared to typical RC column against a catastrophic collapse. Overall, this research broadens the current knowledge of blast and residual capacity analysis of RC framed structures and recommends methods to evaluate and mitigate blast impact on key elements of multi-storey buildings.

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The global financial crisis (GFC) in 2008 rocked local, regional, and state economies throughout the world. Several intermediate outcomes of the GFC have been well documented in the literature including loss of jobs and reduced income. Relatively little research has, however, examined the impacts of the GFC on individual level travel behaviour change. To address this shortcoming, HABITAT panel data were employed to estimate a multinomial logit model to examine mode switching behaviour between 2007 (pre-GFC) and 2009 (post-GFC) of a baby boomers cohort in Brisbane, Australia—a city within a developed country that has been on many metrics the least affected by the GFC. In addition, a Poisson regression model was estimated to model the number of trips made by individuals in 2007, 2008, and 2009. The South East Queensland Travel Survey datasets were used to develop this model. Four linear regression models were estimated to assess the effects of the GFC on time allocated to travel during a day: one for each of the three travel modes including public transport, active transport, less environmentally friendly transport; and an overall travel time model irrespective of mode. The results reveal that individuals were more likely to switch to public transport who lost their job or whose income reduced between 2007 and 2009. Individuals also made significantly fewer trips in 2008 and 2009 compared to 2007. Individuals spent significantly less time using less environmentally friendly transport but more time using public transport in 2009. Baby boomers switched to more environmentally friendly travel modes during the GFC.

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This chapter begins with a discussion of the economic, political, and social context of the recent global financial crisis, which casts into relief current boundaries of criminology, permeated and made fluid in criminology's recent cultural turn. This cultural turn has reinvigorated criminology, providing new objects of analysis and rich and thick descriptions of the relationship between criminal justice and the conditions of life in ‘late modernity’. Yet in comparison with certain older traditions that sought to articulate criminal justice issues with a wider politics of contestation around political economies and social welfare policies of different polities, many of the current leading culturalist accounts tend in their globalized convergences to produce a strangely decontextualized picture in which we are all subject to the zeitgeist of a unitary ‘late modernity’ which does not differ between, for example, social democratic and neo-liberal polities, let alone allow for the widespread persistence of the pre-modern. It is argued that that contrary to this globalizing trend there are signs within criminology that life is being breathed back into social democratic and penal welfare concerns, habitus, and practices. The chapter discusses three of these signs: the emergence of neo-liberalism as a subject of criminology; a developing comparative penology which recognizes differences in the political economies of capitalist states and evinces a renewed interest in inequality; and a nascent revolt against the ‘generative grammar’, ‘pathological disciplinarities’, and ‘imaginary penalities’ of neoliberal managerialism.

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It has become more and more demanding to investigate the impacts of wind farms on power system operation as ever-increasing penetration levels of wind power have the potential to bring about a series of dynamic stability problems for power systems. This paper undertakes such an investigation through investigating the small signal and transient stabilities of power systems that are separately integrated with three types of wind turbine generators (WTGs), namely the squirrel cage induction generator (SCIG), the doubly fed induction generator (DFIG), and the permanent magnet generator (PMG). To examine the effects of these WTGs on a power system with regard to its stability under different operating conditions, a selected synchronous generator (SG) of the well-known Western Electricity Coordinating Council (WECC three-unit nine-bus system and an eight-unit 24-bus system is replaced in turn by each type of WTG with the same capacity. The performances of the power system in response to the disturbances are then systematically compared. Specifically, the following comparisons are undertaken: (1) performances of the power system before and after the integration of the WTGs; and (2) performances of the power system and the associated consequences when the SCIG, DFIG, or PMG are separately connected to the system. These stability case studies utilize both eigenvalue analysis and dynamic time-domain simulation methods.

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Journalists work in an intensively time-pressured environment, researching and writing to daily, often 24 hour, deadlines and always aware of the competition with other news outlets to be first with the news. This results, as Karen Sanders has observed, in journalists having very little time for reflection. “If they do reflect, it’s usually after a decision has been made” (Sanders 2003, 168). Yet time for reflection upon professional practice is important, especially in an era of extremely rapid and seismic technological change in the global media. This paper will reflect upon how freelance journalists can use advances in social media and web-based connectedness to tell global stories via mainstream media outlets. In exploring this question, I will examine the techniques and communications technologies used by three reporters working in the UK and Australia to find, investigate and break a series of articles, published simultaneously on the front pages of The Australian and The Times (London) newspapers, was a result of a six month investigation. The series exposed a 50-year cover-up of the serial abuse of children by one of the Church of England's most senior clergy, Robert Waddington, in Australia and the UK. It unearthed the existence of a culture of physical and sexual abuse at St Barnabas boarding school in Queensland, the sudden closure of the school and disappearance of student files - as well as Waddington's subsequent offences against children while Dean of Manchester Cathedral. We produced more than 20 articles. The coverage sparked church-ordered investigations in both countries, and also prompted the Archbishop of Canterbury to order a commission of inquiry – headed by a sitting UK judge - as well as a nationwide child safety audit of dioceses in Britain. In Australia, the church referred the case and handed its files to the Royal Commission into Child Sexual Abuse. The coverage marked the first publishing collaboration between The Australian and The Times to break an exclusive story in Australia and Britain simultaneously, on May 10, 2013.