1,011 research outputs found

    Dublin City University at CLEF 2006: Experiments for the ImageCLEF Photo Collection Standard Ad Hoc Task

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    We provide a technical description of our submission to the CLEF 2006 Cross Language Image Retrieval(ImageCLEF) Photo Collection Standard Ad Hoc task. We performed monolingual and cross language retrieval of photo images using photo annotations with and without feedback, and also a combined visual and text retrieval approach. Topics are translated into English using the Babelfish online machine translation system. Our text runs used the BM25 algorithm, while our visual approach used simple low-level features with matching based on the Jeffrey Divergence measure. Our results consistently indicate that the fusion of text and visual features is best for this task, and that performing feedback for text consistently improves on the baseline non-feedback BM25 text runs for all language pairs

    Metadata Architecture for Digital Libraries: Conceptual framework for Indian Digital Libraries

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    This paper describes approach of development of Metadata solution for digital library architecture for resource description and retrieval. This deals with the concept of Metadata [2], the different Metadata standards (Dublin core in particular [5]), Digital library environment, computer network capabilities etc. This paper also discusses two of the Digital Library architecture protocols, for resource description and retrieval. They are STARTS (Stanford Protocol Proposal for Internet Retrieval and Search) [8] and SODA (Smart Objects and Dump Archives)[13] architecture to arrive at a possible protocol that would help to build Indian Digital Libraries [5]. While proposing the new architecture the existing Indian environment with respect to information sources and user's query of the information sources [5.1], which are feasible for launch of this protocol for information processing and retrieval has been dealt with. This is a pilot study which the author has done while doing his Fulbright fellowship in the College of Library Information Studies, University of Maryland, College Park, MD during 1999-2000

    The local power of the gradient test

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    The asymptotic expansion of the distribution of the gradient test statistic is derived for a composite hypothesis under a sequence of Pitman alternative hypotheses converging to the null hypothesis at rate n−1/2n^{-1/2}, nn being the sample size. Comparisons of the local powers of the gradient, likelihood ratio, Wald and score tests reveal no uniform superiority property. The power performance of all four criteria in one-parameter exponential family is examined.Comment: To appear in the Annals of the Institute of Statistical Mathematics, this http://www.ism.ac.jp/editsec/aism-e.htm

    The Fisher-Rao metric for projective transformations of the line

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    A conditional probability density function is defined for measurements arising from a projective transformation of the line. The conditional density is a member of a parameterised family of densities in which the parameter takes values in the three dimensional manifold of projective transformations of the line. The Fisher information of the family defines on the manifold a Riemannian metric known as the Fisher-Rao metric. The Fisher-Rao metric has an approximation which is accurate if the variance of the measurement errors is small. It is shown that the manifold of parameter values has a finite volume under the approximating metric. These results are the basis of a simple algorithm for detecting those projective transformations of the line which are compatible with a given set of measurements. The algorithm searches a finite list of representative parameter values for those values compatible with the measurements. Experiments with the algorithm suggest that it can detect a projective transformation of the line even when the correspondences between the components of the measurements in the domain and the range of the projective transformation are unknown

    Anaesthesia for left thoracoscopic sympathectomy for refractory long QT syndrome: three case reports

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    Congenital long QT syndrome (LQTS) is a rare genetic disorder that has been associated with various genetic mutations including life-threatening cardiac arrhythmias and sudden death. Left thoracoscopic sympathectomy is an effective treatment for patients who are refractory to medical therapy or who need frequent epicardial internal cardio defibrillator intervention. The authors report three cases, one adult and two children, who underwent successful left thoracoscopic sympathectomy. All three patients remained clinically stable without arrhythmias through 3 months of follow-up. It is suggested in the literature that 77% of patients experienced immediate relief of symptoms. The results of this case report suggest that left thoracoscopic sympathectomy is a safe and effective approach for treating patients with LQTS.Keywords: congenital condition, left cardiac sympathetic denervation, left thoracic sympathectomy, prolonged QT syndrome, video-assisted thoracoscopic surger

    Generation of ultrashort electrical pulses in semiconductor waveguides

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    We report a novel device capable of generating ultrashort electrical pulses on a coplanar waveguide (CPW) by means of optical rectification. The device consists of a completely passive GaAs-based optical waveguide, which is velocity matched to a CPW line. Optical pulses are injected into the device and electrical pulses are collected at the output. Experimental results obtained in the laboratory show the potential of this device for high speed optical-to-electrical conversion

    Intellectual Property Rights of Electronic Information in the Age of Digital Convergence

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    The laws of intellectual property aim to protect owners of the literary, dramatic, musical, and artistic works; designs, innovations and inventions from unauthorized use or exploitation by some one else. Though every country has enacted laws to protect intellectual property of its citizens, many infringements take place and a majority of them end up in courts of law. The developments in information and communication technologies made the situation grimmer. This paper briefly explains the copyright and protection of electronic information, its security in network environment, and copyright provisions for databases, multimedia works, and computer software. The relevant provisions of the European Union, the American and the Indian legislative developments as well as the international efforts were touched. The various facets of the information Technology Act and the recently tabled Communications Convergence Bill have been discussed. Despite all the legislative efforts, a level playing field is needed for the rights owners, publishers, library professionals and user

    Time without time: a stochastic clock model

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    We study a classical reparametrization-invariant system, in which ``time'' is not a priori defined. It consists of a nonrelativistic particle moving in five dimensions, two of which are compactified to form a torus. There, assuming a suitable potential, the internal motion is ergodic or more strongly irregular. We consider quasi-local observables which measure the system's ``change'' in a coarse-grained way. Based on this, we construct a statistical timelike parameter, particularly with the help of maximum entropy method and Fisher-Rao information metric. The emergent reparametrization-invariant ``time'' does not run smoothly but is simply related to the proper time on the average. For sufficiently low energy, the external motion is then described by a unitary quantum mechanical evolution in accordance with the Schr\"odinger equation.Comment: 18 pages; LaTeX. 4 (.ps) plus 2 (.gif) figure file

    EPR and optical absorption studies of Fe3 ions in sodium borophosphate glasses

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    Electron paramagnetic resonance (EPR) and optical absorption spectral investigations have been carried out on Fe3 ions doped sodium borophosphate glasses (NaH2PO4B2O 3Fe2O3). The EPR spectra exhibit resonance signals with effective g values at g=2.02, g=4.2 and g=6.4. The resonance signal at g=4.2 is due to isolated Fe3 ions in site with rhombic symmetry whereas the g=2.02 resonance is due to Fe3 ions coupled by exchange interaction in a distorted octahedral environment. The EPR spectra at different temperatures (123295 K) have also been studied. The intensity of the resonance signals decreases with increase in temperature whereas linewidth is found to be independent of temperature. The paramagnetic susceptibility (Ï) was calculated from the EPR data at various temperatures and the Curie constant (C) and paramagnetic Curie temperature (ξp) have been evaluated from the 1/Ï versus T graph. The optical absorption spectrum exhibits bands characteristic of Fe3 ions in octahedral symmetry. The crystal field parameter (Dq) and the Racah interelectronic repulsion parameters (B and C) have also been evaluated and discussed. © 2010 Elsevier Ltd

    H-1 NMR study of molecular dynamics and phase transitions in (CH3NH3) 2PbBr6 and [N(CH3)(4)](2)SeCl6.

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    The proton spin-lattice relaxation time (T-1) has been measured in methylammonium hexabromoplumbate, (CH3NH3)(2)PbBr6, in the range 77-450K and tetramethylammonium (TMA) hexachloroselenate, [N(CH3)(4) ](2)SeCl6 in the range 77-430K In (CH3NH3)(2)PbBr6, T-1 shows a slope change at 415K, a minimum at 215K, and a discontinuous jump at 167K In [N(CH3)(4)](2)SeCl6, T-1 shows a slope change at 340K and goes through a narrow symmetric minimum at 194K. Further, it exhibits a shoulder-like structure at 106K and goes through a broad minimum at 85K. Motional parameters such as activation energy and preexponential factor have been evaluated for the reorientational motion of CH3-NH3 groups and the TMA ion in different phases
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