3,264 research outputs found

    Water Quality Analysis of the Lake and Weather Studies at Keoladeo National Park, Bharatpur

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    Keoladeo National Park, situated between 27⁰ 7.6' to 27⁰ 12.2' N and 77⁰ 29.5 to 77⁰ 33.9' E, is two Southeast of the Bharatpur city, 38 Km Southwest of Mathura and 50 Km West of Agra. Delhi is 180 Km. North of Bharatpur. The total area of the park is about 29 Sq.Km. It is flat with a gentle slope towards the centre forming a depression, the total area of which is about 8.5 Sq.Km. This is a main submersible area of the park. The average elevation of the area is about 174 meters. The submersible area has been divided into various unequal compartments by means of dykes

    Video Object Detection with an Aligned Spatial-Temporal Memory

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    We introduce Spatial-Temporal Memory Networks for video object detection. At its core, a novel Spatial-Temporal Memory module (STMM) serves as the recurrent computation unit to model long-term temporal appearance and motion dynamics. The STMM's design enables full integration of pretrained backbone CNN weights, which we find to be critical for accurate detection. Furthermore, in order to tackle object motion in videos, we propose a novel MatchTrans module to align the spatial-temporal memory from frame to frame. Our method produces state-of-the-art results on the benchmark ImageNet VID dataset, and our ablative studies clearly demonstrate the contribution of our different design choices. We release our code and models at http://fanyix.cs.ucdavis.edu/project/stmn/project.html

    Band Structure Calculation of Momentum Density in Ruthenium

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    Simple Analytical Particle and Kinetic Energy Densities for a Dilute Fermionic Gas in a d-Dimensional Harmonic Trap

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    We derive simple analytical expressions for the particle density ρ(r)\rho(r) and the kinetic energy density τ(r)\tau(r) for a system of noninteracting fermions in a dd-dimensional isotropic harmonic oscillator potential. We test the Thomas-Fermi (TF, or local-density) approximation for the functional relation τ[ρ]\tau[\rho] using the exact ρ(r)\rho(r) and show that it locally reproduces the exact kinetic energy density τ(r)\tau(r), {\it including the shell oscillations,} surprisingly well everywhere except near the classical turning point. For the special case of two dimensions (2D), we obtain the unexpected analytical result that the integral of τTF[ρ(r)]\tau_{TF}[\rho(r)] yields the {\it exact} total kinetic energy.Comment: 4 pages, 4 figures; corrected versio

    A Quantum Mechanical Model of Spherical Supermembranes

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    We present a quantum mechanical model of spherical supermembranes. Using superfields to represent the cartesian coordinates of the membrane, we are able to exactly determine its supersymmetric vacua. We find there are two classical vacua, one corresponding to an extended membrane and one corresponding to a point-like membrane. For the N=2{\mathcal N} = 2 case, instanton effects then lift these vacua to massive states. For the N=4{\mathcal N} = 4 case, there is no instanton tunneling, and the vacua remain massless. Similarities to spherical supermembranes as giant gravitons and in Matrix theory on pp-waves is discussed.Comment: 9 page

    JAMI: a Java library for molecular interactions and data interoperability.

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    BACKGROUND: A number of different molecular interactions data download formats now exist, designed to allow access to these valuable data by diverse user groups. These formats include the PSI-XML and MITAB standard interchange formats developed by Molecular Interaction workgroup of the HUPO-PSI in addition to other, use-specific downloads produced by other resources. The onus is currently on the user to ensure that a piece of software is capable of read/writing all necessary versions of each format. This problem may increase, as data providers strive to meet ever more sophisticated user demands and data types. RESULTS: A collaboration between EMBL-EBI and the University of Cambridge has produced JAMI, a single library to unify standard molecular interaction data formats such as PSI-MI XML and PSI-MITAB. The JAMI free, open-source library enables the development of molecular interaction computational tools and pipelines without the need to produce different versions of software to read different versions of the data formats. CONCLUSION: Software and tools developed on top of the JAMI framework are able to integrate and support both PSI-MI XML and PSI-MITAB. The use of JAMI avoids the requirement to chain conversions between formats in order to reach a desired output format and prevents code and unit test duplication as the code becomes more modular. JAMI's model interfaces are abstracted from the underlying format, hiding the complexity and requirements of each data format from developers using JAMI as a library

    Open-Retrieval Conversational Question Answering

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    Conversational search is one of the ultimate goals of information retrieval. Recent research approaches conversational search by simplified settings of response ranking and conversational question answering, where an answer is either selected from a given candidate set or extracted from a given passage. These simplifications neglect the fundamental role of retrieval in conversational search. To address this limitation, we introduce an open-retrieval conversational question answering (ORConvQA) setting, where we learn to retrieve evidence from a large collection before extracting answers, as a further step towards building functional conversational search systems. We create a dataset, OR-QuAC, to facilitate research on ORConvQA. We build an end-to-end system for ORConvQA, featuring a retriever, a reranker, and a reader that are all based on Transformers. Our extensive experiments on OR-QuAC demonstrate that a learnable retriever is crucial for ORConvQA. We further show that our system can make a substantial improvement when we enable history modeling in all system components. Moreover, we show that the reranker component contributes to the model performance by providing a regularization effect. Finally, further in-depth analyses are performed to provide new insights into ORConvQA.Comment: Accepted to SIGIR'2

    New gas-filled mode of the large-acceptance spectrometer VAMOS

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    Spectromètre VAMOSA new gas-filled operation mode of the large-acceptance spectrometer VAMOS at GANIL is reported. A beam rejection factor greater than 1010 is obtained for the 40Ca+150Sm system at 196 MeV. The unprecedented transmission efficiency for the evaporation residues produced in this reaction is estimated to be around 80% for ®xn channels and above 95% for xnyp channels. A detailed study of the performance of the gasfilled VAMOS and future developments are discussed. This new operation mode opens avenues to explore the potential of fusion reactions in various kinematics

    Electromagnetic transition from the 4+^+ to 2+^+ resonance in 8^8Be measured via the radiative capture in 4^4He+4^4He

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    An earlier measurement on the 4+^+ to 2+^+ radiative transition in 8^8Be provided the first electromagnetic signature of its dumbbell-like shape. However, the large uncertainty in the measured cross section does not allow a stringent test of nuclear structure models. The present paper reports a more elaborate and precise measurement for this transition, via the radiative capture in the 4^4He+4^4He reaction, improving the accuracy by about a factor of three. The {\it ab initio} calculations of the radiative transition strength with improved three-nucleon forces are also presented. The experimental results are compared with the predictions of the alpha cluster model and {\it ab initio} calculations.Comment: 5 pages and 7 figures, Submitted to Physical Review Letter
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