158 resultados para Lead times


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Identifying unusual or anomalous patterns in an underlying dataset is an important but challenging task in many applications. The focus of the unsupervised anomaly detection literature has mostly been on vectorised data. However, many applications are more naturally described using higher-order tensor representations. Approaches that vectorise tensorial data can destroy the structural information encoded in the high-dimensional space, and lead to the problem of the curse of dimensionality. In this paper we present the first unsupervised tensorial anomaly detection method, along with a randomised version of our method. Our anomaly detection method, the One-class Support Tensor Machine (1STM), is a generalisation of conventional one-class Support Vector Machines to higher-order spaces. 1STM preserves the multiway structure of tensor data, while achieving significant improvement in accuracy and efficiency over conventional vectorised methods. We then leverage the theory of nonlinear random projections to propose the Randomised 1STM (R1STM). Our empirical analysis on several real and synthetic datasets shows that our R1STM algorithm delivers comparable or better accuracy to a state-of-the-art deep learning method and traditional kernelised approaches for anomaly detection, while being approximately 100 times faster in training and testing.

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Because the worldwide demand for sperm donors is much higher than the actual supply available through fertility clinics, an informal online market has emerged for sperm donation. Very little empirical evidence exists, however, on this newly formed market and even less on the characteristics that lead to donor success. This article therefore explores the determinants of online sperm donors’ selection success, which leads to the production of offspring via informal donation. We find that donor age and income play a significant role in donor success as measured by the number of times selected, even though there is no requirement for ongoing paternal investment. Donors with less extroverted and lively personality traits who are more intellectual, shy and systematic are more successful in realizing offspring via informal donation. These results contribute to both the economic literature on human behaviour and on large-scale decision-making.

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The unknown future is a challenge to educators in preparing young people for life post school. While history can be said to repeat itself, the reality is that each generation is faced with new challenges and threats. Therefore, the challenge for contemporary schooling is to prepare students to live in a fast paced, complex world where threats such as terrorism, cyberbullying and depleted resources are juggled with high stakes testing and curriculum accountability. This presentation draws on the notion of a future of supercomplexity while critically examining current pastoral care delivery in schools to develop a new model of practice in preparing students for an unknown future.

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Lead germanate-graphene nanosheets (PbGeO3-GNS) composites have been prepared by an efficient one-step, in-situ hydrothermal method and were used as anode materials for Li-ion batteries (LIBs). The PbGeO3 nanowires, around 100–200 nm in diameter, are highly encapsulated in a graphene matrix. The lithiation and de-lithiation reaction mechanisms of the PbGeO3 anode during the charge-discharge processes have been investigated by X-ray diffraction and electrochemical characterization. Compared with pure PbGeO3 anode, dramatic improvements in the electrochemical performance of the composite anodes have been obtained. In the voltage window of 0.01–1.50 V, the composite anode with 20 wt.% GNS delivers a discharge capacity of 607 mAh g−1 at 100 mA g−1 after 50 cycles. Even at a high current density of 1600 mA g−1, a capacity of 406 mAh g−1 can be achieved. Therefore, the PbGeO3-GNS composite can be considered as a potential anode material for lithium ion batteries.

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Methylammonium bismuth (III) iodide single crystals and films have been developed and investigated. We have further presented the first demonstration of using this organic–inorganic bismuth-based material to replace lead/tin-based perovskite materials in solution-processable solar cells. The organic–inorganic bismuth-based material has advantages of non-toxicity, ambient stability, and low-temperature solution-processability, which provides a promising solution to address the toxicity and stability challenges in organolead- and organotin-based perovskite solar cells. We also demonstrated that trivalent metal cation-based organic–inorganic hybrid materials can exhibit photovoltaic effect, which may inspire more research work on developing and applying organic-inorganic hybrid materials beyond divalent metal cations (Pb (II) and Sn (II)) for solar energy applications.

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At any given time in the field of early childhood, there are discourses at play, producing images of children, and these ways of seeing children might be competing, colliding and/or complementing each other. It is fairly widely accepted that in many countries there are versions of dominant discourses that shape and are shaped by current practices in the field of early childhood. These include (1) romantic notions of children running free and connecting with nature and (2) the ‘Bart Simpson’ version of the naughty, cute or savage child, untamed and in need of civilising. These are far from being the only two discursive constructions of children present in current policies and practices. If early childhood professionals are to be active in shaping and implementing policies that affect their work and workforce, it is important that they are aware of the forces at play. In this article, we point to another powerful discourse at play in the Australian context of early childhood education, the image of children as economic units: investments in the future. We show how a ‘moment of arising’ in contemporary policy contexts, dominated by neoliberal principles of reform and competition, has charged early childhood educators in Australia with the duties of a ‘broker’, ensuring that young children are worth the investment. In this article, we begin with (1) a key policy document in early childhood education in Australia and examine the discursive affordances which shape the document. Next, (2) we pinpoint the shifts in how the work of child care is perceived by interrogating this key policy document through a methodology of discursive analysis. We then turn attention (3) to the work of this policy document along with other discourses which directly affect images of children and the shaping role these have on the work of educators. We conclude with (4) a consideration of how the work of early childhood professionals has come to be shaped by this economic discourse, and how they are being required to both work within the policy imperatives and likely to resist this new demand of them.

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Historically, organized labor has played a fundamental role in guaranteeing basic rights and privileges for screen media workers and defending union and guild members (however unevenly) from egregious abuses of power. Yet, despite the recent turn to labor in media and cultural studies, organized labor today has received only scant attention, even less so in locations outside Hollywood. This presentation thus intervenes in two significant ways: first, it acknowledges the ongoing global ‘undoing’ of organized labor as a consequence of footloose production and conglomeration within the screen industries, and second, it examines a case example of worker solidarity and political praxis taking shape outside formal labor institutions in response to those structural shifts. Accordingly, it links an empirical study of individual agency to broader debates associated with the spatial dynamics of screen media production, including local capacity, regional competition, and precariousness. Drawing from ethnographic interviews with local film and television workers in Glasgow, Scotland, I consider the political alliance among three nascent labor organizations in the city: one for below-the-line crew, one for facility operators, and (oddly enough) one for producers. Collectively, the groups share a desire to transform Glasgow into a global production hub, following the infrastructure developments in nearby cities like Belfast, Prague, and Budapest. They furthermore frame their objectives in political terms: establishing global scale is considered a necessary maneuver to improve local working conditions like workplace safety, income disparity, skills training, and job access. Ultimately, I argue these groups are a product of an inadequate union structure and outdated policy vision for the screen sector , once-supportive institutions currently out of sync with the global realities of media production. Furthermore, the groups’ advocacy efforts reveal the extent to which workers themselves (in additional to capital) can seek “spatial fixes” to suture their prospects to specific political and economic goals. Of course, such activities manifest under conditions outside of the workers’ control but nevertheless point to an important tension within capitalist social relations, namely that the agency to reshape the spatial relationships in their own lives recasts the geography of labor in terms that aren’t inherent or exclusive to the interests of global capital.

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Manhattan gains another nocturnal landmark in the form of a new skyscraper, built for the well-established newspaper and featuring an illuminated façade. Architectual historian and lighting journalist Margaret Maile reports for us from New York.