7,619 research outputs found

    Segmenting broadcast news streams using lexical chains

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    In this paper we propose a course-grained NLP approach to text segmentation based on the analysis of lexical cohesion within text. Most work in this area has focused on the discovery of textual units that discuss subtopic structure within documents. In contrast our segmentation task requires the discovery of topical units of text i.e. distinct news stories from broadcast news programmes. Our system SeLeCT first builds a set of lexical chains, in order to model the discourse structure of the text. A boundary detector is then used to search for breaking points in this structure indicated by patterns of cohesive strength and weakness within the text. We evaluate this technique on a test set of concatenated CNN news story transcripts and compare it with an established statistical approach to segmentation called TextTiling

    SeLeCT: a lexical cohesion based news story segmentation system

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    In this paper we compare the performance of three distinct approaches to lexical cohesion based text segmentation. Most work in this area has focused on the discovery of textual units that discuss subtopic structure within documents. In contrast our segmentation task requires the discovery of topical units of text i.e., distinct news stories from broadcast news programmes. Our approach to news story segmentation (the SeLeCT system) is based on an analysis of lexical cohesive strength between textual units using a linguistic technique called lexical chaining. We evaluate the relative performance of SeLeCT with respect to two other cohesion based segmenters: TextTiling and C99. Using a recently introduced evaluation metric WindowDiff, we contrast the segmentation accuracy of each system on both "spoken" (CNN news transcripts) and "written" (Reuters newswire) news story test sets extracted from the TDT1 corpus

    Interrelationships between tracking performance measures, control dynamics, and the effects of incentives

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    Interrelationships between tracking performance measures, control dynamics, and effects of incentive

    Thin-film flow in helically wound rectangular channels with small torsion

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    Laminar gravity-driven thin-film flow down a helically-wound channel of rectangular cross-section with small torsion in which the fluid depth is small is considered. Neglecting the entrance and exit regions we obtain the steady-state solution that is independent of position along the axis of the channel, so that the flow, which comprises a primary flow in the direction of the axis of the channel and a secondary flow in the cross-sectional plane, depends only on position in the two-dimensional cross-section of the channel. A thin-film approximation yields explicit expressions for the fluid velocity and pressure in terms of the free-surface shape, the latter satisfying a non-linear ordinary differential equation that has a simple exact solution in the special case of a channel of rectangular cross-section. The predictions of the thin-film model are shown to be in good agreement with much more computationally intensive solutions of the small-helix-torsion Navier–Stokes equations. The present work has particular relevance to spiral particle separators used in the mineral-processing industry. The validity of an assumption commonly used in modelling flow in spiral separators, namely that the flow in the outer region of the separator cross-section is described by a free vortex, is shown to depend on the problem parameters

    Towards developing an industry led educational framework using LEAN approach

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    The poor performance and inefficient manner in which the construction industry operates has been recognised through a variety of combined government and industry initiatives over the years. A major challenge towards improvement is recognised as lying with education and industry stakeholders actively creating closer and more effective relationships to facilitate a greater mutual understanding. The application of Information Technology (IT) systems can well enhance ‘Lean’ initiatives through improving process flow, reduction of the non-added value activities, better meet customers’ requirements and adding value which will increase the performance of the industry. This paper presents a project that is focused on developing an industry led framework for educational training programmes. The outcomes of two workshops organised with the industry that have resulted in a Continued Professional Development (CPD) training framework comprising of three distinct levels in terms of strategic, operational and technology aspects of that particular key area are discussed. The essence of this work is based on adopting the ‘Lean’ approach and adding value by identifying the IT skills gaps recognised ‘by the industry’ ‘for the industry’ and addressing them in developing training programmes

    Parametric analysis of microwave and laser systems for communication and tracking. Volume 2 - System selection

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    System selection criteria of microwave and laser systems for communication and tracking - Vol.

    Monte Carlo aided design of the inner muon veto detectors for the Double Chooz experiment

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    The Double Chooz neutrino experiment aims to measure the last unknown neutrino mixing angle theta_13 using two identical detectors positioned at sites both near and far from the reactor cores of the Chooz nuclear power plant. To suppress correlated background induced by cosmic muons in the detectors, they are protected by veto detector systems. One of these systems is the inner muon veto. It is an active liquid scintillator based detector and instrumented with encapsulated photomultiplier tubes. In this paper we describe the Monte Carlo aided design process of the inner muon veto, that resulted in a detector configuration with 78 PMTs yielding an efficiency of 99.978 +- 0.004% for rejecting muon events and an efficiency of >98.98% for rejecting correlated events induced by muons. A veto detector of this design is currently used at the far detector site and will be built and incorporated as the muon identification system at the near site of the Double Chooz experiment

    Alimentary Toxaemia in Epilepsy

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    Comparison of Parent-Child Interactions in Abusive and Control Families: An Observational Study

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    This study sought to identify differences in caregiver-child interactions between caregivers with and without prior reports of child physical abuse. Data for the abuse group were made available for secondary analyses by the National Archive for Child Abuse and Neglect via Cornell University. Data for the comparison group were collected for a previous study at West Virginia University. For both studies, caregiver-child dyads participated in a 5---minute, videotaped observation in a situation in which the parent had to exert moderate control over the child. Data that had been coded using the Dyadic Parent---Child Interaction Coding System (Eyberg, et al., 1994; Eyberg, et al., 2005) were compared in 70 caregiver-child dyads. Groups were similar with regard to child behavior, parent age, child gender, parental education level, caregiver marital status, and relation of parent to child. Analyses were conducted with both the sample of 70 dyads, in which children in the abuse group were older, and with a subsample of 41 dyads, in which all children were 4- to 5-years-old and significantly more caregivers in the abuse group were male. Race was considered in both sets of analyses. Results with both samples revealed that, over and above demographic differences, parents in the abuse group talked significantly more and, after additionally controlling for total talk, gave significantly less praise. These results inform parental fitness examinations, but observations should be examined within a broader assessment. Limitations of this study include comparison of two pre-existing samples with some procedural and sample differences. Future research should consider demographic differences when examining caregiver-child differences in abusive samples and attempt to include fathers

    Experiment definition phase shuttle laboratory (LDRL-10.6 experiment): Shuttle sortie to elliptical orbit satellite

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    The following topics were reviewed: (1) design options for shuttle terminal, (2) elliptical orbit satellite design options, (3) shuttle terminal details, (4) technology status and development requirements, (5) transmitter technology, and (6) carbon dioxide laser life studies
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