950 resultados para Search Strategies


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High contrast ratios between windows and surrounding surfaces could cause reduced visibility or discomfort for occupants. Consequently, building users may choose to intervene in lighting conditions through closing blinds and turning on the lamps in order to enhance indoor visual comfort. Such interventions increase projected electric lighting use in buildings. One simple method to prevent these problematic issues is increasing the luminance of the areas surrounding to the bright surface of windows through the use of energy-efficient supplementary lighting, such Light Emitting Diodes (LEDs). This paper reports on the results of a pilot study in conventional office in Brisbane, Australia. The outcomes of this study indicated that a supplementary LED system of approximately 18 W could reduce the luminance contrast on the window wall from values in the order of 117:1 to 33:1. In addition, the results of this experiment suggested that this supplementary strategy could increase the subjective scale appraisal of window appearance by approximately 33%, as well as reducing the likelihood of users’ intention to turn on the ceiling lights by about 27%. It could also diminish the likelihood of occupants’ intention to move the blind down by more than 90%.

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Young Australian drivers aged 17 – 25 years are overwhelmingly represented in road fatalities where speed is a factor. In the combined LGAs of Armidale Dumaresq, Guyra, Uralla and Walcha in the 5 years 1999-2003 inclusive, 43% of speeding related casualty crashes involved a young driver aged less than 25 years. This is despite the fact that the 17-25 age group account for only 25% of the driving population in this area. Young male drivers account for the majority of these crashes and also tend to have a higher number of driving offences and accrue more penalties for road traffic offences, especially speeding. By analysing data from questionnaires by male and female participants this research project has been able to evaluate road safety advertisements to determine which ones are most effective to young drivers, what features of these advertisements are effective, how males differ from females in their receptiveness and preferences for road safety advertisements and specifically how to target young people especially young men in conveying road safety messages. Finally this research project has identified factors that are important in the production of media road safety advertisements and has made recommendations for how best to convey effective road safety messages to young Australian drivers in rural areas.

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In this paper we explore how small and medium-sized enterprises (SMEs) engage in external knowledge sourcing, a form of inbound open innovation. We draw upon a sample of 1,411 SMEs and empirically conceptualize a typology of strategic types of external knowledge sourcing, namely minimal, supply-chain, technology-oriented, application-oriented, and full-scope sourcing. Each strategy reflects the nature of external interactions and is linked to a distinct mixture of four internal practices for managing innovation. Both full-scope and application-oriented sourcing offer performance benefits and are associated with a stronger focus on managing innovation. However, they differ in their managerial focus on strategic and operational aspects.

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Bone metastasis is a complication that occurs in 80 % of women with advanced breast cancer. Despite the prevalence of bone metastatic disease, the avenues for its clinical management are still restricted to palliative treatment options. In fact, the underlying mechanisms of breast cancer osteotropism have not yet been fully elucidated due to a lack of suitable in vivo models that are able to recapitulate the human disease. In this work, we review the current transplantation-based models to investigate breast cancer-induced bone metastasis and delineate the strengths and limitations of the use of different grafting techniques, tissue sources, and hosts. We further show that humanized xenograft models incorporating human cells or tissue grafts at the primary tumor site or the metastatic site mimic more closely the human disease. Tissue-engineered constructs are emerging as a reproducible alternative to recapitulate functional humanized tissues in these murine models. The development of advanced humanized animal models may provide better platforms to investigate the mutual interactions between human cancer cells and their microenvironment and ultimately improve the translation of preclinical drug trials to the clinic.

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Previous qualitative research has highlighted that temporality plays an important role in relevance for clinical records search. In this study, an investigation is undertaken to determine the effect that the timespan of events within a patient record has on relevance in a retrieval scenario. In addition, based on the standard practise of document length normalisation, a document timespan normalisation model that specifically accounts for timespans is proposed. Initial analysis revealed that in general relevant patient records tended to cover a longer timespan of events than non-relevant patient records. However, an empirical evaluation using the TREC Medical Records track supports the opposite view that shorter documents (in terms of timespan) are better for retrieval. These findings highlight that the role of temporality in relevance is complex and how to effectively deal with temporality within a retrieval scenario remains an open question.

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We developed a theoretical framework to organize obesity prevention interventions by their likely impact on the socioeconomic gradient of weight. The degree to which an intervention involves individual agency versus structural change influences socioeconomic inequalities in weight. Agentic interventions, such as standalone social marketing, increase socioeconomic inequalities. Structural interventions, such as food procurement policies and restrictions on unhealthy foods in schools, show equal or greater benefit for lower socioeconomic groups. Many obesity prevention interventions belong to the agento–structural types of interventions, and account for the environment in which health behaviors occur, but they require a level of individual agency for behavioral change, including workplace design to encourage exercise and fiscal regulation of unhealthy foods or beverages. Obesity prevention interventions differ in their effectiveness across socioeconomic groups. Limiting further increases in socioeconomic inequalities in obesity requires implementation of structural interventions. Further empirical evaluation, especially of agento–structural type interventions, remains crucial.

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A high contrast ratio between windows and surrounding walls may lead to office workers visual discomfort that could negatively affect their satisfaction and productivity. Consequently, occupants may try to adapt their working environment by closing blinds and/ or turning on the lights to enhance indoor visual comfort, which can reduce predicted energy savings. The hypothesis of this study is that reducing luminance contrast ratio on the window wall will improve window appearance which potentially will reduce visual discomfort and decrease workers interventions. Thus, this PhD research proposes a simple strategy to diminish the luminance contrast on the window wall by increasing the luminance of the areas surrounding the windows using supplementary light emitting diode (LED) systems. To test the hypothesis, this investigation will involve three experiments in different office layouts with various window types and orientations in Brisbane, Australia. It will assess user preferences for different luminance patterns in windowed offices featuring flexible, lowpower LED lighting installations that allows multiple lighting design options on the window wall. Detailed luminance and illuminance measures will be used to match quantitative lighting design assessment to user preferences.

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In this paper, we propose a new load distribution strategy called `send-and-receive' for scheduling divisible loads, in a linear network of processors with communication delay. This strategy is designed to optimally utilize the network resources and thereby minimizes the processing time of entire processing load. A closed-form expression for optimal size of load fractions and processing time are derived when the processing load originates at processor located in boundary and interior of the network. A condition on processor and link speed is also derived to ensure that the processors are continuously engaged in load distributions. This paper also presents a parallel implementation of `digital watermarking problem' on a personal computer-based Pentium Linear Network (PLN) topology. Experiments are carried out to study the performance of the proposed strategy and results are compared with other strategies found in literature.

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The passion to eradicate alterity from the earth is also the passion for the home, the country, the dwelling, that authorizes this desire and rewards it. In its nationalism, parochialism and racism it constitutes a public and private neurosis. So, unwinding the rigid understanding of place that apparently permits me to speak, that guarantees my voice, my power, is not simply to disperse my locality within the wider coordinates of an ultimate planetary context. That would merely absolve me of responsibility in the name of an abstract and generic globalism, permitting my inheritance to continue uninterrupted in the vagaries of a new configuration. There is something altogether more precise and more urgent involved. For in the horror of the unhomely pulses the dread for the dispersal of Western humankind: the dread of a rationality confronted with what exceeds and slips its grasp. (Chambers, 2001, p. 196)

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In a search for inorganic oxide materials showing second-order nonlinear optical (NLO) susceptibility, we investigated several berates, silicates, and a phosphate containing trans-connected MO6, octahedral chains or MO5 square pyramids, where, M = d(0): Ti(IV), Nb(V), or Ta(V), Our investigations identified two new NLO structures: batisite, Na2Ba(TiO)(2)Si4O12, containing trans-connected TiO5 octahedral chains, and fresnoite, Ba2TiOSi2O7, containing square-pyramidal TiO5. Investigation of two other materials containing square-pyramidal TiO5 viz,, Cs2TiOP2O7 and Na4Ti2Si8O22. 4H(2)O, revealed that isolated TiO5, square pyramids alone do not cause a second harmonic generation (SHG) response; rather, the orientation of TiO5 units to produce -Ti-O-Ti-O- chains with alternating long and short Ti-O distances in the fresnoite structure is most likely the origin of a strong SHG response in fresnoite,

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Cooperation among unrelated individuals is an enduring evolutionary riddle and a number of possible solutions have been suggested. Most of these suggestions attempt to refine cooperative strategies, while little attention is given to the fact that novel defection strategies can also evolve in the population. Especially in the presence of punishment to the defectors and public knowledge of strategies employed by the players, a defecting strategy that avoids getting punished by selectively cooperating only with the punishers can get a selective benefit over non-conditional defectors. Furthermore, if punishment ensures cooperation from such discriminating defectors, defectors who punish other defectors can evolve as well. We show that such discriminating and punishing defectors can evolve in the population by natural selection in a Prisoner’s Dilemma game scenario, even if discrimination is a costly act. These refined defection strategies destabilize unconditional defectors. They themselves are, however, unstable in the population. Discriminating defectors give selective benefit to the punishers in the presence of non-punishers by cooperating with them and defecting with others. However, since these players also defect with other discriminators they suffer fitness loss in the pure population. Among the punishers, punishing cooperators always benefit in contrast to the punishing defectors, as the latter not only defect with other punishing defectors but also punish them and get punished. As a consequence of both these scenarios, punishing cooperators get stabilized in the population. We thus show ironically that refined defection strategies stabilize cooperation. Furthermore, cooperation stabilized by such defectors can work under a wide range of initial conditions and is robust to mistakes.

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A modeling paradigm is proposed for covariate, variance and working correlation structure selection for longitudinal data analysis. Appropriate selection of covariates is pertinent to correct variance modeling and selecting the appropriate covariates and variance function is vital to correlation structure selection. This leads to a stepwise model selection procedure that deploys a combination of different model selection criteria. Although these criteria find a common theoretical root based on approximating the Kullback-Leibler distance, they are designed to address different aspects of model selection and have different merits and limitations. For example, the extended quasi-likelihood information criterion (EQIC) with a covariance penalty performs well for covariate selection even when the working variance function is misspecified, but EQIC contains little information on correlation structures. The proposed model selection strategies are outlined and a Monte Carlo assessment of their finite sample properties is reported. Two longitudinal studies are used for illustration.

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The 2008 US election has been heralded as the first presidential election of the social media era, but took place at a time when social media were still in a state of comparative infancy; so much so that the most important platform was not Facebook or Twitter, but the purpose-built campaign site my.barackobama.com, which became the central vehicle for the most successful electoral fundraising campaign in American history. By 2012, the social media landscape had changed: Facebook and, to a somewhat lesser extent, Twitter are now well-established as the leading social media platforms in the United States, and were used extensively by the campaign organisations of both candidates. As third-party spaces controlled by independent commercial entities, however, their use necessarily differs from that of home-grown, party-controlled sites: from the point of view of the platform itself, a @BarackObama or @MittRomney is technically no different from any other account, except for the very high follower count and an exceptional volume of @mentions. In spite of the significant social media experience which Democrat and Republican campaign strategists had already accumulated during the 2008 campaign, therefore, the translation of such experience to the use of Facebook and Twitter in their 2012 incarnations still required a substantial amount of new work, experimentation, and evaluation. This chapter examines the Twitter strategies of the leading accounts operated by both campaign headquarters: the ‘personal’ candidate accounts @BarackObama and @MittRomney as well as @JoeBiden and @PaulRyanVP, and the campaign accounts @Obama2012 and @TeamRomney. Drawing on datasets which capture all tweets from and at these accounts during the final months of the campaign (from early September 2012 to the immediate aftermath of the election night), we reconstruct the campaigns’ approaches to using Twitter for electioneering from the quantitative and qualitative patterns of their activities, and explore the resonance which these accounts have found with the wider Twitter userbase. A particular focus of our investigation in this context will be on the tweeting styles of these accounts: the mixture of original messages, @replies, and retweets, and the level and nature of engagement with everyday Twitter followers. We will examine whether the accounts chose to respond (by @replying) to the messages of support or criticism which were directed at them, whether they retweeted any such messages (and whether there was any preferential retweeting of influential or – alternatively – demonstratively ordinary users), and/or whether they were used mainly to broadcast and disseminate prepared campaign messages. Our analysis will highlight any significant differences between the accounts we examine, trace changes in style over the course of the final campaign months, and correlate such stylistic differences with the respective electoral positioning of the candidates. Further, we examine the use of these accounts during moments of heightened attention (such as the presidential and vice-presidential debates, or in the context of controversies such as that caused by the publication of the Romney “47%” video; additional case studies may emerge over the remainder of the campaign) to explore how they were used to present or defend key talking points, and exploit or avert damage from campaign gaffes. A complementary analysis of the messages directed at the campaign accounts (in the form of @replies or retweets) will also provide further evidence for the extent to which these talking points were picked up and disseminated by the wider Twitter population. Finally, we also explore the use of external materials (links to articles, images, videos, and other content on the campaign sites themselves, in the mainstream media, or on other platforms) by the campaign accounts, and the resonance which these materials had with the wider follower base of these accounts. This provides an indication of the integration of Twitter into the overall campaigning process, by highlighting how the platform was used as a means of encouraging the viral spread of campaign propaganda (such as advertising materials) or of directing user attention towards favourable media coverage. By building on comprehensive, large datasets of Twitter activity (as of early October, our combined datasets comprise some 3.8 million tweets) which we process and analyse using custom-designed social media analytics tools, and by using our initial quantitative analysis to guide further qualitative evaluation of Twitter activity around these campaign accounts, we are able to provide an in-depth picture of the use of Twitter in political campaigning during the 2012 US election which will provide detailed new insights social media use in contemporary elections. This analysis will then also be able to serve as a touchstone for the analysis of social media use in subsequent elections, in the USA as well as in other developed nations where Twitter and other social media platforms are utilised in electioneering.

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This thesis discusses the contemporary construction of the lived worlds of indigenous Amazonian youths. Today’s native peoples are considerably affected by the processes of globalization and urbanization, which have led to new ways of relating to their cultural traditions. This work presents a case study of Manchineri youngsters aged between 14 and 24 years old living in Acre state in Brazilian Amazonia. The Arawak-speaking Manchineri number some 1,000 people; their legally demarcated reserve is situated next to the River Yaco. The research is based on ethnographic material collected in the Mamoadate reserve and in the state capital, Rio Branco. By comparing the youth in different physical and social environments (the reserve and the city), my attempt has been to search for the most typical elements maintained, altered and created in the current lived worlds of Manchineri youths. Fieldwork methods included interviews, participant observation, photographs, video recordings, and drawings. The material was analyzed within the multidisciplinary framework of the social and cultural construction of knowledge. The study applies the concepts of social field, symbolic capital, and habitus as they have been used by Pierre Bourdieu; perspective as developed recently in Amazonian ethnology; the sacred as a cultural category as understood in the study of religion; and individual and person as concepts central to anthropology and sociology. Additionally, the study can be contextualized within youth studies, Latin American studies, and urban studies. The results of the study show that the everyday lives of young Amazonian native people are formed by a complex mixture of ‘modernity’ and ‘tradition’, fragmentation, and transitions between different conceptual frameworks. Part II discusses the ethnographic material in depth and shows that indigenous adolescents act from a variety of social perspectives: the native youth’s own ethnic group, divided into sub-groups, especially into urban residents and those living in the reserve; ancestors, super-human agents and spirits; other indigenous groups and non-natives. Consequently, besides the traditional initiation ritual, we find various contemporary rites of passage to adulthood: state-education, learning traditional practices, shamanism, matrimony, and transitions between the reserve and urban areas. According to these results, new social roles, political organization, responsibilities, and in general the desire to be respected, require both ‘modern’ and ‘traditional’ abilities. In Part III, the study shows that the current power relations constituted by new social contacts, ethnic recognition, and cooperation with different institutions have resulted in the formation of new social fields: youth cultures, the ethnic group, shamanic practices, the ethnopolitical movement, and indigenous students. The capacity of young Amazonian Indians to act in contemporary social fields produces them as full persons. The study also argues that the elements of the lived worlds can be divided into these social fields. When focusing on these fields, it became evident that these comprise the strategies adopted by young Indians to break through social and cultural barriers.