• Title/Summary/Keyword: resolution-independent

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Spatio-temporal models for generating a map of high resolution NO2 level

  • Yoon, Sanghoo;Kim, Mingyu
    • Journal of the Korean Data and Information Science Society
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    • v.27 no.3
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    • pp.803-814
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    • 2016
  • Recent times have seen an exponential increase in the amount of spatial data, which is in many cases associated with temporal data. Recent advances in computer technology and computation of hierarchical Bayesian models have enabled to analyze complex spatio-temporal data. Our work aims at modeling data of daily average nitrogen dioxide (NO2) levels obtained from 25 air monitoring sites in Seoul between 2003 and 2010. We considered an independent Gaussian process model and an auto-regressive model and carried out estimation within a hierarchical Bayesian framework with Markov chain Monte Carlo techniques. A Gaussian predictive process approximation has shown the better prediction performance rather than a Hierarchical auto-regressive model for the illustrative NO2 concentration levels at any unmonitored location.

Moving Target Tracking and Recognition for Location Based Surveillance Service (위치기반 감시 서비스를 위한 이동 객체 추적 및 인식)

  • Kim, Hyun;Park, Chan-Ho;Woo, Jong-Woo;Doo, Seok-Bae
    • Proceedings of the IEEK Conference
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    • 2008.06a
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    • pp.1211-1212
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    • 2008
  • In this paper, we propose image process modeling as a part of location based surveillance system for unauthorized target recognition and tracking in harbor, airport, military zone. For this, we compress and store background image in lower resolution and perform object extraction and motion tracking by using sobel edge detection and difference picture method between real images and a background image. In addition to, we use Independent Component Analysis Neural Network for moving target recognition. Experiments are performed for object extraction and tracking of moving targets on road by using static camera in 20m height building and it shows the robust results.

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지구관측위성 현황 조사

  • Shin, Jae-Min;Kim, Hee-Seob;Kim, Eung-Hyun;Im, Jung-Heum
    • Aerospace Engineering and Technology
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    • v.2 no.1
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    • pp.63-72
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    • 2003
  • On the basis of sensor types, satellites can be classified by two types, which are optical observation satellite and radar observation satellite. A satellite type is selected according to the specific mission. Optical observation satellite is more appropriate for getting high geometric resolution images and radar observation satellite is more appropriate for getting images independent of weather condition the more a demand of satellite increases, the more an importance of information increases. Therefore, development trend and state of earth observation satellite are surveyed and described in this paper. In the future, domestic development of satellites will be planned considering trend of satellite technologies.

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Basic Design of CBTC System Based on ERTMS/ETCS (ERTMS/ETCS 기반의 CBTC 시스템 기본설계)

  • Yang, Chan-Seok;Lim, Jae-Shik;Um, Jung-Kyou;Han, Jae-Mun;Bang, Yung;Kim, Hyoung-Hoon
    • Proceedings of the KSR Conference
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    • 2007.11a
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    • pp.629-632
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    • 2007
  • Communications Based Train Control(CBTC) is a continuous, automatic train control system utilizing high-resolution, train location determination independent of track circuits; continuous, high capacity, bi-directional train-to-wayside data communications; and trainborne and wayside processors capable of implementing vital functions. In this paper, we present a basic design of CBTC system based on ERTMS/ETCS specifications. The basic design is composed of system requirements analysis, system functional analysis, system architectural design, sub-system requirements analysis, sub-system functional analysis. Each deliverable has been produced according to a development process based on UML/SysML.

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Speech Feature Extraction Based on the Human Hearing Model

  • Chung, Kwang-Woo;Kim, Paul;Hong, Kwang-Seok
    • Proceedings of the KSPS conference
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    • 1996.10a
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    • pp.435-447
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    • 1996
  • In this paper, we propose the method that extracts the speech feature using the hearing model through signal processing techniques. The proposed method includes the following procedure ; normalization of the short-time speech block by its maximum value, multi-resolution analysis using the discrete wavelet transformation and re-synthesize using the discrete inverse wavelet transformation, differentiation after analysis and synthesis, full wave rectification and integration. In order to verify the performance of the proposed speech feature in the speech recognition task, korean digit recognition experiments were carried out using both the DTW and the VQ-HMM. The results showed that, in the case of using DTW, the recognition rates were 99.79% and 90.33% for speaker-dependent and speaker-independent task respectively and, in the case of using VQ-HMM, the rate were 96.5% and 81.5% respectively. And it indicates that the proposed speech feature has the potential for use as a simple and efficient feature for recognition task

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Nonlinear Dynamical Friction of a Circular-orbit Perturber in a Uniform Gaseous Medium

  • Kim, Ung-Tae
    • The Bulletin of The Korean Astronomical Society
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    • v.35 no.1
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    • pp.72.2-72.2
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    • 2010
  • We use three-dimensional hydrodynamic simulations to investigate nonlinear gravitational responses of gas to, and the resulting drag force on, a massive perturber moving on a circular orbit through a uniform gaseous medium. We assume that the background medium is non-rotating and adiabatic with index 5/3, and represent the perturber using a Plummer potential with softening radius a. This work extends our previous study where we showed that the drag force on a straight-line trajectory is proportional to a0.45 if the perturber is massive enough. This indicates that the orbital decay of supermassive black holes (SMBHs) near galaxy centers may take much longer than the prediction of the linear force formula applicable for low-mass perturbers. For the circular orbits are considered, however, we find that the nonlinear drag force becomes independent of a, but dependent instead on the orbital radius R as $\varpropto$ R0.5. This suggests not only that the choices of large values of a, for resolution issues, in recent numerical experiments for mergers of SMBH, are marginally acceptable, but also that the gaseous drag indeed provides an efficient mean for the orbtial decay of SMBHs.

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ULTRAFAST INTERFACIAL ELECTRON TRAPPING AND RECOMBINATION IN PHOTOEXCITED COLLOIDAL CADMIUM SULFIDE

  • Kim, Seong-Kyu
    • Journal of Photoscience
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    • v.4 no.1
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    • pp.11-16
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    • 1997
  • We measured, using femtosecond pump-probe experiment, the time evolution of transient absorption in aqueous CdS colloids. The signal rises within the time resolution (= 0.5 ps) of the experiment and decays with two exponential time constants, 4.8 ps and 132 ps. The ultrafast rise of the transient absorption is considered to be for shallowly trapped conduction band electrons after photoexcitation. The amplitude ratio of the two decaying components varies with the pump intensity and the decay times increase in the presence of hole scavengers. Even though a biexponential function fits the decay well, we object hat two independent first order processes (geminate and nongeminate recombinations) are responsible for the decay. A function with an integrated rate equation for second order nongeminate recombination plus a long background fits the decay well. The long background is considered to be for deeply trapped charges at the CdS particle.

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Generation of Fixed Spectral Basis for Three-Dimensional Mesh Coding Using Dual Graph

  • Kim Sung-Yeol;Yoon Seung-Uk;Ho Yo-Sung
    • Proceedings of the IEEK Conference
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    • summer
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    • pp.137-142
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    • 2004
  • In this paper, we propose a new scheme for geometry coding of three-dimensional (3-D) mesh models using a fixed spectral basis. In order to code the mesh geometry information, we generate a fixed spectral basis using the dual graph derived from the 3-D mesh topology. After we partition a 3-D mesh model into several independent sub-meshes to reduce coding complexity, the mesh geometry information is projected onto the generated orthonormal bases which are the eigenvectors of the Laplacian matrix of the 3-D mesh. Finally, spectral coefficients are coded by a quantizer and a variable length coder. The proposed scheme can not only overcome difficulty of generating a fixed spectral basis, but also reduce coding complexity. Moreover, we can provide an efficient multi-resolution representation of 3-D meshes.

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A Study on the Challenge of a Arbitrator (중재인의 기피에 관한 고찰)

  • 이명우
    • Journal of Arbitration Studies
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    • v.13 no.2
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    • pp.403-424
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    • 2004
  • In the solutions of civil disputes, there are decision of a court and alternative dispute resolution. Arbitration is one of alternative dispute resolutions. The decision of a court is the compulsory settlement and the solution by citizenship between two opposing parties, but arbitration is the autonomous and voluntary settlement by a private person, that is arbitrator. Besides these points, arbitration has various features in comparison with a decision of a court. The procedure of arbitration is not open to the public and single trial system guarantees speedy solution of disputes In the procedure of arbitration, arbitrator who pass judgement is selected and appointed by the parties to an affair. And there are questions how the arbitrator to become independent from them. Because Arbitration is not agreed solution which based on the concession between opposing two parties but imposed solution which is alike decision of a court. This study illustrates the system of challenge on arbitrator to guarantee independence of arbitrators.

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A Study of Shorted-Turn Detection in the Cylindrical Synchronous Generator Rotor Windings via Discrete Wavelet Transform (이산 웨이브렛 변환을 이용한 동기발전기 회전자 층간단락 진단에 관한 연구)

  • Kim, Y.J.;Kim, J.M.
    • Proceedings of the KIPE Conference
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    • 2005.07a
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    • pp.476-478
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    • 2005
  • This paper describes a method for the detection of shorted-turn in the cylindrical synchronous generator rotor windings based on the discrete wavelet transform. Multi-resolution analysis(MRA) based on discrete wavelet transform provides a set of decomposed signals in independent frequency bands. In the proposed method, shorted-turn detection in rotor windings is based on the decomposition of the rotor currents, where wavelet coefficients of these signals have been extracted. Comparing these extracted coefficients is used for diagnosing the healthy machine from faulty machine. Experimental results show the effectiveness of the proposed method for shorted-turn detection in the cylindrical synchronous generator rotor windings.

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