136 resultados para feature writing


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The subcellular localization of transmissible gastroenteritis virus (TGEV) and mouse hepatitis virus (MHV) (group I and group II coronaviruses, respectively) nucleoproteins (N proteins) were examined by confocal microscopy. The proteins were shown to localize either to the cytoplasm alone or to the cytoplasm and a structure in the nucleus. This feature was confirmed to be the nucleolus by using specific antibodies to nucleolin, a major component of the nucleolus, and by confocal microscopy to image sections through a cell expressing N protein. These findings are consistent with our previous report for infectious bronchitis virus (group III coronavirus) (J. A. Hiscox et al., J. Virol. 75:506-512, 2001), indicating that nucleolar localization of the N protein is a common feature of the coronavirus family and is possibly of functional significance. Nucleolar localization signals were identified in the domain III region of the N protein from all three coronavirus groups, and this suggested that transport of N protein to the nucleus might be an active process. In addition, our results suggest that the N protein might function to disrupt cell division. Thus, we observed that approximately 30% of cells transfected with the N protein appeared to be undergoing cell division. The most likely explanation for this is that the N protein induced a cell cycle delay or arrest, most likely in the G2/M phase. In a fraction of transfected cells expressing coronavirus N proteins, we observed multinucleate cells and dividing cells with nucleoli (which are only present during interphase). These findings are consistent with the possible inhibition of cytokinesis in these cells.

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Gaussian multi-scale representation is a mathematical framework that allows to analyse images at different scales in a consistent manner, and to handle derivatives in a way deeply connected to scale. This paper uses Gaussian multi-scale representation to investigate several aspects of the derivation of atmospheric motion vectors (AMVs) from water vapour imagery. The contribution of different spatial frequencies to the tracking is studied, for a range of tracer sizes, and a number of tracer selection methods are presented and compared, using WV 6.2 images from the geostationary satellite MSG-2.

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A new class of shape features for region classification and high-level recognition is introduced. The novel Randomised Region Ray (RRR) features can be used to train binary decision trees for object category classification using an abstract representation of the scene. In particular we address the problem of human detection using an over segmented input image. We therefore do not rely on pixel values for training, instead we design and train specialised classifiers on the sparse set of semantic regions which compose the image. Thanks to the abstract nature of the input, the trained classifier has the potential to be fast and applicable to extreme imagery conditions. We demonstrate and evaluate its performance in people detection using a pedestrian dataset.

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It has been shown through a number of experiments that neural networks can be used for a phonetic typewriter. Algorithms can be looked on as producing self-organizing feature maps which correspond to phonemes. In the Chinese language the utterance of a Chinese character consists of a very simple string of Chinese phonemes. With this as a starting point, a neural network feature map for Chinese phonemes can be built up. In this paper, feature map structures for Chinese phonemes are discussed and tested. This research on a Chinese phonetic feature map is important both for Chinese speech recognition and for building a Chinese phonetic typewriter.

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Variations on the standard Kohonen feature map can enable an ordering of the map state space by using only a limited subset of the complete input vector. Also it is possible to employ merely a local adaptation procedure to order the map, rather than having to rely on global variables and objectives. Such variations have been included as part of a hybrid learning system (HLS) which has arisen out of a genetic-based classifier system. In the paper a description of the modified feature map is given, which constitutes the HLSs long term memory, and results in the control of a simple maze running task are presented, thereby demonstrating the value of goal related feedback within the overall network.

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The academic discipline of television studies has been constituted by the claim that television is worth studying because it is popular. Yet this claim has also entailed a need to defend the subject against the triviality that is associated with the television medium because of its very popularity. This article analyses the many attempts in the later twentieth and twenty-first centuries to constitute critical discourses about television as a popular medium. It focuses on how the theoretical currents of Television Studies emerged and changed in the UK, where a disciplinary identity for the subject was founded by borrowing from related disciplines, yet argued for the specificity of the medium as an object of criticism. Eschewing technological determinism, moral pathologization and sterile debates about television's supposed effects, UK writers such as Raymond Williams addressed television as an aspect of culture. Television theory in Britain has been part of, and also separate from, the disciplinary fields of media theory, literary theory and film theory. It has focused its attention on institutions, audio-visual texts, genres, authors and viewers according to the ways that research problems and theoretical inadequacies have emerged over time. But a consistent feature has been the problem of moving from a descriptive discourse to an analytical and evaluative one, and from studies of specific texts, moments and locations of television to larger theories. By discussing some historically significant critical work about television, the article considers how academic work has constructed relationships between the different kinds of objects of study. The article argues that a fundamental tension between descriptive and politically activist discourses has confused academic writing about ›the popular‹. Television study in Britain arose not to supply graduate professionals to the television industry, nor to perfect the instrumental techniques of allied sectors such as advertising and marketing, but to analyse and critique the medium's aesthetic forms and to evaluate its role in culture. Since television cannot be made by ›the people‹, the empowerment that discourses of television theory and analysis aimed for was focused on disseminating the tools for critique. Recent developments in factual entertainment television (in Britain and elsewhere) have greatly increased the visibility of ›the people‹ in programmes, notably in docusoaps, game shows and other participative formats. This has led to renewed debates about whether such ›popular‹ programmes appropriately represent ›the people‹ and how factual entertainment that is often despised relates to genres hitherto considered to be of high quality, such as scripted drama and socially-engaged documentary television. A further aspect of this problem of evaluation is how television globalisation has been addressed, and the example that the issue has crystallised around most is the reality TV contest Big Brother. Television theory has been largely based on studying the texts, institutions and audiences of television in the Anglophone world, and thus in specific geographical contexts. The transnational contexts of popular television have been addressed as spaces of contestation, for example between Americanisation and national or regional identities. Commentators have been ambivalent about whether the discipline's role is to celebrate or critique television, and whether to do so within a national, regional or global context. In the discourses of the television industry, ›popular television‹ is a quantitative and comparative measure, and because of the overlap between the programming with the largest audiences and the scheduling of established programme types at the times of day when the largest audiences are available, it has a strong relationship with genre. The measurement of audiences and the design of schedules are carried out in predominantly national contexts, but the article refers to programmes like Big Brother that have been broadcast transnationally, and programmes that have been extensively exported, to consider in what ways they too might be called popular. Strands of work in television studies have at different times attempted to diagnose what is at stake in the most popular programme types, such as reality TV, situation comedy and drama series. This has centred on questions of how aesthetic quality might be discriminated in television programmes, and how quality relates to popularity. The interaction of the designations ›popular‹ and ›quality‹ is exemplified in the ways that critical discourse has addressed US drama series that have been widely exported around the world, and the article shows how the two critical terms are both distinct and interrelated. In this context and in the article as a whole, the aim is not to arrive at a definitive meaning for ›the popular‹ inasmuch as it designates programmes or indeed the medium of television itself. Instead the aim is to show how, in historically and geographically contingent ways, these terms and ideas have been dynamically adopted and contested in order to address a multiple and changing object of analysis.

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