• Title/Summary/Keyword: $D^*$criterion

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Fast key-frame extraction for 3D reconstruction from a handheld video

  • Choi, Jongho;Kwon, Soonchul;Son, Kwangchul;Yoo, Jisang
    • International journal of advanced smart convergence
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    • v.5 no.4
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    • pp.1-9
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    • 2016
  • In order to reconstruct a 3D model in video sequences, to select key frames that are easy to estimate a geometric model is essential. This paper proposes a method to easily extract informative frames from a handheld video. The method combines selection criteria based on appropriate-baseline determination between frames, frame jumping for fast searching in the video, geometric robust information criterion (GRIC) scores for the frame-to-frame homography and fundamental matrix, and blurry-frame removal. Through experiments with videos taken in indoor space, the proposed method shows creating a more robust 3D point cloud than existing methods, even in the presence of motion blur and degenerate motions.

Sliding Window Filtering for Ground Moving Targets with Cross-Correlated Sensor Noises

  • Song, Il Young;Song, Jin Mo;Jeong, Woong Ji;Gong, Myoung Sool
    • Journal of Sensor Science and Technology
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    • v.28 no.3
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    • pp.146-151
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    • 2019
  • This paper reports a sliding window filtering approach for ground moving targets with cross-correlated sensor noise and uncertainty. In addition, the effect of uncertain parameters during a tracking error on the model performance is considered. A distributed fusion sliding window filter is also proposed. The distributed fusion filtering algorithm represents the optimal linear combination of local filters under the minimum mean-square error criterion. The derivation of the error cross-covariances between the local sliding window filters is the key to the proposed method. Simulation results of the motion of the ground moving target a demonstrate high accuracy and computational efficiency of the distributed fusion sliding window filter.

Distributed Fusion Moving Average Prediction for Linear Stochastic Systems

  • Song, Il Young;Song, Jin Mo;Jeong, Woong Ji;Gong, Myoung Sool
    • Journal of Sensor Science and Technology
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    • v.28 no.2
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    • pp.88-93
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    • 2019
  • This paper is concerned with distributed fusion moving average prediction for continuous-time linear stochastic systems with multiple sensors. A distributed fusion with the weighted sum structure is applied to the optimal local moving average predictors. The distributed fusion prediction algorithm represents the optimal linear fusion by weighting matrices under the minimum mean square criterion. The derivation of equations for error cross-covariances between the local predictors is the key of this paper. Example demonstrates effectiveness of the distributed fusion moving average predictor.

Efficient Design of 2-D FIR Fan Filters Using New Formulas for McClellan Transform Parameters

  • Song, Young-Seog;Lee, Yong-Hoon
    • Journal of Electrical Engineering and information Science
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    • v.1 no.1
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    • pp.160-163
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    • 1996
  • New formulas for McClellan transform parameters for the design of 2-D zero-phase FIR fan filters are optimally derived under the integral squared error(ISE) criterion. By imposing the constraint that F(0, 0)=\ulcorner, where F($.$) is the McClellan transform and $\omega$\ulcorner is the cutoff frequency of the 1-D prototype filter, the ISE is directly minimized without modifying it and, as a consequence, closed-form formulas for the McClellan transform parameters are obtained. It is shown that these formulas lead to a very efficient design for 2-D zero-phase FIR fan filters.

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An analysis on the network performance for VoD services using multicast (멀티캐스트를 이용한 VoD 서비스망의 성능 분석)

  • 백남균;정수환;민병준
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.25 no.6A
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    • pp.918-926
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    • 2000
  • A huge storage and broad bandwidth are required to provide subscribers with VoD services. Hence, there is a huge amount of cost in establishing networks for VoD services. To determine how to reduce the cost, a number of studies involving such as distributed server systems, multicasting, program caching, stream sharing, are currently in progress. In this paper, a request criterion for multicast service and the ratio of required bandwidth for unicast to multicast are generated. The effect of multicast service on network bandwidth, server bandwidth, and buffer size was analyzed and validated through computer simulation. The results of this study could be applied to efficient designing networks for VoD services.

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IMPLEMENTATION OF TRL TOOLS TO KOREAN NATIONAL CONSTRUCTION AND TRANSPORTATION R&D PROJECTS FOR IMPROVING PRACTICAL USE

  • Namgyun Kim;Byungho An;Jaehong Choi;Hyunseok Lee;Sanghyuk Park;Yeasang Kim
    • International conference on construction engineering and project management
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    • 2013.01a
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    • pp.608-615
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    • 2013
  • The major countries including Korea extend the national investment on R&D and implement the business performance diffusion policy as the knowledge based competition age arrives recently. The necessity for risk management and systematic management system for R&D achievement have been appeared to prevent the failure as the R&D scale becomes larger as it was said. For this matter, the organization such as NASA and DoD in USA defines the Technology Readiness Level (TRL) as a quantitative accomplishment management index and utilize the Technology Readiness Assessment (TRA) system as a criterion. Such tool is evaluated as very effective in the R&D project purposed the practicalization. It is expected that the disadvantage of evaluation system which is oriented to the academic accomplishment in its contents of current research and to contribute greatly to the practicalization of outcomes when such technology readiness level concept is applied to Korean national construction and transportation R&D project. Accordingly, this study analyzed the concept of TRL·TRA, the characteristics and current evaluation management system of Korean national construction and transportation R&D project and suggested the construction and transportation R&D project TRL·TRA performance model to accomplish the practicalization purpose.

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A Fault Tolerant ATM Switch using a Fully Adaptive Self-routing Algorithm - The Cyclic Banyan Network (실내 무선 통신로에서 파일럿 심볼을 삽입한 Concatenated FEC 부호에 의한 WATM의 성능 개선)

  • 박기식;강영흥;김종원;정해원;양해권;조성준
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.24 no.9A
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    • pp.1276-1284
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    • 1999
  • We have evaluated the BER's and CLP's of Wireless ATM (WATM) cells employing the concatenated FEC code with pilot symbols for fading compensation through the simulation in indoor wireless channel modeled as a Rayleigh and a Rician fading channel, respectively. The results of the performance evaluation are compared with those obtained by employing the convolutional code in the same condition. In Rayleigh fading channel, considering the maximum tolerance BER ( $10^-3$) as a criterion of the voice service, it is blown that the performance improvement of about 4 dB is obtained in terms of $E_b/N_o$ by employing the concatenated FEC code with pilot symbols rather than the convolutional code with pilot symbols.When the values of K parameter which means the ratio of the direct signal to scattered signal power in Rician fading channel are 6 and 10, it is shown that the performance improvement of about 4 dB and 2 dB is obtained, respectively, in terms of $E_b/N_o$ by employing the concatenated FEC code with pilot symbols considering the maximum tolerance BER of the voice service. Also in Rician fading channel of K=6 and K= 10, considering CLP = $10^-3$ as a criterion, it is observed that the performance improvement of about 3.5 dB and1.5 dB is obtained, respectively, in terms of $E_b/N_o$ by employing the concatenated FEC code with pilot symbols.

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A Study on the Change of Paradigm and Analysis of Qualitative Space in Public Space - Focused on the Entrance Floor in General Hospital over 500 beds in Korea - (공용 공간의 패러다임 변화와 질적 공간 분석 - 500병상 이상 국내 종합병원 진입층을 중심으로 -)

  • Son, Ji-Hye;Yang, Nae-Won
    • Korean Institute of Interior Design Journal
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    • v.23 no.6
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    • pp.212-220
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    • 2014
  • Entrance floor in hospital has became important space for medical service in holistic perspective and image enhancement. However, basically a discussion of the qualitative properties and the role of public space is paucity in change of public spaces paradigm. In accordance with this problem, this study consider the change of paradigm in public space based on earlier studies and create classification criterion of space. According to the criterion, G/D ratio and the qualitative spatial area ratio of 26 general hospitals which were planned over 500 beds are analyzed by case study method. The conclusion of this study is as follows. 1) The space according to the medical function is variable element. So the public space should be planned from function-subordinate space to self-reliance space in the future. 2) There is no correlation between the high G/D ratio and the high ratio of qualitative spacial area. In other word It's hard to say that the public space which G/D ratio is high is qualitative space. 3) Since 2000, various types in accordance with the circulation system is applied to public space. And ratio of qualitative spacial area is relatively high in the street type and the concourse type. 4) The qualitative spatial area ratio of stay space is higher than passage's one.

Composite Design Criteria : Model and Variance (복합실험기준의 설정: 모형과 분산구조)

  • 김영일
    • The Korean Journal of Applied Statistics
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    • v.13 no.2
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    • pp.393-405
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    • 2000
  • Box and Draper( 19(5) listed some properties of a design that should be considered in design selection. But it is impossible that one design criterion from optimal experimental design theory reflects many potential objectives of an experiment, because the theory was originally based on the underlying model and its strict assumption about the error structure. Therefore, when it is neces::;ary to implement multi-objective experimental design. it is common practice to balance out the several optimal design criteria so that each design criterion involved benefits in terms of its relative "high" efficiency. In this study, we proposed several composite design criteria taking the case of heteroscedastic model. WVhen the heteroscedasticity is present in the model. the well known equivalence theorem between 1)- and C-optimality no longer exists and furthermore their design characteristics are sometimes drastically different. We introduced three different design criteria for this purpose: constrained design, combined design, and minimax design criteria. While the first two methods do reflect the prior belief of experimenter, the last one does not take it into account. which is sometimes desirable. Also we extended this method to the case when there are uncertainties concerning the error structure in the model. A simple algorithm and concluslOn follow.On follow.

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Effect of Crystal Structural Environment of Pr3+ on Photoluminescence Characteristics of Double Tungstates

  • Lee, Kyoung-Ho;Chae, Ki-Woong;Cheon, Chae-Il;Kim, Jeong-Seog
    • Journal of the Korean Ceramic Society
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    • v.48 no.2
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    • pp.183-188
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    • 2011
  • In this article, the effect of the crystal structural environment of $Pr^{3+}$ ions on the photoluminescence (PL) characteristics of double tungstates, such as $A(M_{1-X}Pr_X)W_2O_8$ (A=Li, Cs, M = In, Y, Sc, La; $0.007{\leq}x{\leq}0.1$) and $La_{1.96}Pr_{0.04}W_3O_{12}$ are characterized. By varying the ion radius in A and M sites, the structural environment of $Pr^{3+}$ ions were modified. The structural criteria, that is, the point charge electrostatic potentials V around the $Pr^{3+}$ activator, were calculated using the crystal structural parameters. The point charge potential V can be a valid criterion for $^3P_o$ quenching in various double tungstates. When the calculated V values are large (> 6.0), the luminescence from the $^3P_0$ level becomes dominant. When the calculated V values are about 3.8, the $^1D_2$ line appears weakly but $^3P_0$-level luminescence is absent. When the calculated V values are small (< 2.0), the luminescence from the $^1D_2$ level becomes dominant and $^3P_0$-level luminescence is absent. At 2.0$^3P_o$ quenching to $^1D_2$ level occurs substantially in accordance with the structural criterion of the point charge potential model.