• Title/Summary/Keyword: Reconstruction error

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Gesture Classification Based on k-Nearest Neighbors Algorithm for Game Interface (게임 인터페이스를 위한 최근접 이웃알고리즘 기반의 제스처 분류)

  • Chae, Ji Hun;Lim, Jong Heon;Lee, Joon Jae
    • Journal of Korea Multimedia Society
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    • v.19 no.5
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    • pp.874-880
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    • 2016
  • The gesture classification has been applied to many fields. But it is not efficient in the environment for game interface with low specification devices such as mobile and tablet, In this paper, we propose a effective way for realistic game interface using k-nearest neighbors algorithm for gesture classification. It is time consuming by realtime rendering process in game interface. To reduce the process time while preserving the accuracy, a reconstruction method to minimize error between training and test data sets is also proposed. The experimental results show that the proposed method is better than the conventional methods in both accuracy and time.

Automatic Generation of the Input Data for Rapid Prototyping from Unorganized Point Cloud Data (임의의 점 군 데이터로부터 쾌속조형을 위한 입력데이터의 자동생성)

  • Yoo, Dong-Jin
    • Journal of the Korean Society for Precision Engineering
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    • v.24 no.11
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    • pp.144-153
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    • 2007
  • In order to generate the input data for rapid prototyping, a new approach which is based on the implicit surface interpolation method is presented. In the method a surface is reconstructed by creating smooth implicit surface from unorganized cloud of points through which the surface should pass. In the method an implicit surface is defined by the adaptive local shape functions including quadratic polynomial function, cubic polynomial function and RBF(Radial Basis Function). By the reconstruction of a surface, various types of error in raw STL file including degenerated triangles, undesirable holes with complex shapes and overlaps between triangles can be eliminated automatically. In order to get the slicing data for rapid prototyping an efficient intersection algorithm between implicit surface and plane is developed. For the direct usage for rapid prototyping, a robust transformation algorithm for the generation of complete STL data of solid type is also suggested.

Three-dimensional Reconstruction Using Boundary Detection of CT Images (CT 영상 경계 검출을 이용한 3차원 재구성)

  • Yoo, S.K.;Yang, H.;Kim, S.H.;Kim, N.H.;Kim, W.K.;Park, S.H.
    • Journal of Biomedical Engineering Research
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    • v.9 no.2
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    • pp.153-158
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    • 1988
  • A three-dimensional surface is reconstructed from contour information as identified on two-dimensional computed tomographic slices. Gradient operator with curvature constraint would be applied to extract the contour automatically, and backtracking is also adopted to reduce the tracking error. The surface between the consecutive slice is efficiently reconstructed using a triangular surface tiles. Hidden surface elimination, shading and parallel projection of the reconstructed surface are provied on the display screen.

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Extracting 2D-Mesh from Structured Light Image for Reconstructing 3D Faces (3차원 얼굴 복원을 위한 구조 광 영상에서의 2차원 메쉬 추출)

  • Lee, Duk-Ryong;Oh, Il-Seok
    • Proceedings of the Korea Contents Association Conference
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    • 2007.11a
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    • pp.248-251
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    • 2007
  • In this paper, we are propose a method to estimate the 2-D mesh from structured light image for reconstruction of 3-D face image. To acquire the structured light image, we are project structured light on the face using the projector. we are extract the projected cross points from the acquire image. The 2-D mesh image is extracted from the position and angle of cross points. In the extraction processing, the error was fixed to extract the correct 2-D mesh.

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Wavelet Compression Method with Minimum Delay for Mobile Tele-cardiology Applications (이동형 Tele-cardiology 시스템 적용을 위한 최저 지연을 가진 웨이브릿 압축 기법)

  • Kim Byoung-Soo;Yoo Sun-Kook;Lee Moon-Hyoung
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.53 no.11
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    • pp.786-792
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    • 2004
  • A wavelet based ECG data compression has become an attractive and efficient method in many mobile tele-cardiology applications. But large data size required for high compression performance leads a serious delay. In this paper, new wavelet compression method with minimum delay is proposed. It is based on deciding the type and compression ratio(CR) of block organically according to the standard deviation of input ECG data with minimum block size. Compression performances of the proposed algorithm for different MIT ECG Records were analyzed comparing other ECG compression algorithm. In addition to the processing delay measurement, compression efficiency and reconstruction sensitivity to error were also evaluated via random noise simulation models. The results show that the proposed algorithm has both lower PRD than other algorithm on same CR and minimum time in the data acquisition, processing and transmission.

Nonlinearity-Compensation Extended Kalman Filter for Handling Unexpected Measurement Uncertainty in Process Tomography

  • Kim, Jeong-Hoon;Ijaz, Umer Zeeshan;Kim, Bong-Seok;Kim, Min-Chan;Kim, Sin;Kim, Kyung-Youn
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.1897-1902
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    • 2005
  • The objective of this paper is to estimate the concentration distribution in flow field inside the pipeline based on electrical impedance tomography. Special emphasis is given to the development of dynamic imaging technique for two-phase field undergoing a rapid transient change. Nonlinearity-compensation extended Kalman filter is employed to cope with unexpected measurement uncertainty. The nonlinearity-compensation extended Kalman filter compensates for the influence of measurement uncertainty and solves the instability of extended Kalman filter. Extensive computer simulations are carried out to show that nonlinearity-compensation extended Kalman filter has enhanced estimation performance especially in the unexpected measurement environment.

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Intelligent Gain and Boundary Layer Based Sliding Mode Control for Robotic Systems with Unknown Uncertainties

  • Yoo, Sung-Jin;Park, Jin-Bae;Choi, Yoon-Ho
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.2319-2324
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    • 2005
  • This paper proposes a intelligent gain and boundary layer based sliding mode control (SMC) method for robotic systems with unknown model uncertainties. For intelligent gain and boundary layer, we employ the self recurrent wavelet neural network (SRWNN) which has the properties such as a simple structure and fast convergence. In our control structure, the SRWNNs are used for estimating the width of boundary layer, uncertainty bound, and nonlinear terms of robotic systems. The adaptation laws for all parameters of SRWNNs and reconstruction error bounds are derived from the Lyapunov stability theorem, which are used for an on-line control of robotic systems with unknown uncertainties. Accordingly, the proposed method can overcome the chattering phenomena in the control effort and has the robustness regardless of unknown uncertainties. Finally, simulation results for the three-link manipulator, one of the robotic systems, are included to illustrate the effectiveness of the proposed method.

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Self-Recurrent Wavelet Neural Network Based Adaptive Backstepping Control for Steering Control of an Autonomous Underwater Vehicle (수중 자율 운동체의 방향 제어를 위한 자기회귀 웨이블릿 신경회로망 기반 적응 백스테핑 제어)

  • Seo, Kyoung-Cheol;Yoo, Sung-Jin;Park, Jin-Bae;Choi, Yoon-Ho
    • Journal of Institute of Control, Robotics and Systems
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    • v.13 no.5
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    • pp.406-413
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    • 2007
  • This paper proposes a self-recurrent wavelet neural network(SRWNN) based adaptive backstepping control technique for the robust steering control of autonomous underwater vehicles(AUVs) with unknown model uncertainties and external disturbance. The SRWNN, which has the properties such as fast convergence and simple structure, is used as the uncertainty observer of the steering model of AUV. The adaptation laws for the weights of SRWNN and reconstruction error compensator are induced from the Lyapunov stability theorem, which are used for the on-line control of AUV. Finally, simulation results for steering control of an AUV with unknown model uncertainties and external disturbance are included to illustrate the effectiveness of the proposed method.

A Study on Obstacle Reasons of BIM in Construction Phase (시공단계에서의 BIM 도입 저해요인에 관한 기초연구)

  • Kim, Ji-Sun;Yoo, Seung-Kyu;Kim, Ju-Hyung;Kim, Jae-Jun
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2011.11a
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    • pp.61-62
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    • 2011
  • Construction plans for large construction projects are problems such as Incompatibility of information, omissions due to technical limitations of 2D CAD. In addition to, Plan established for the validation such as process, cost and construction technology plan is difficult. By occurring Frequent changes in the course of business, Inefficiency of management has occurred. In the construction process, there is occurred costs and construction delays due to reconstruction or communication error. In this study, It was deemed BIM will complement Existing 2D CAD problem. And, BIM case studies in the construction phase of domestic construction were analyzed, How to apply BIM in the construction phase investigated.

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Aliasing Effect in Sound Field Reconstruction using Acoustic Holography (음향 홀로그래피를 이용한 음장구성에 따른 앨리애싱 영향)

  • 권휴상;김양한
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 1993.04a
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    • pp.123-127
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    • 1993
  • 소음방사의 이해 및 효과적인 소음제어를 위해서는 소음원의 특성, 음장의 공간상 방사 특성 등을 아는 것이 중요하며, 이를 위해 많은 연구가 진행되 어 왔다. 특히 다수의 마이크로폰 어레이를 이용한 음향 홀로그래피 방법에 의한 실험적 음장 예측 방법이 소개되었고 연구가 진행됨에 따라 많은 실용 가능성을 보여 주었다. 음향 홀로그래피 방법에는 측정상 제한이 필연적으로 존재할 수밖에 없는데, 이에 따른 오차가 존재하며 결국 예측음장의 신뢰도 를 떨어뜨리는 요인이 된다. 본 연구의 목적은 측정조건에 따른 오차의 요인 을 고찰하고 이를 정량적으로 표현함으로써 음향 홀로그래피 방법의 적용에 도움을 주고자 한다. 평면 음향 홀로그래피에 나타나는 오차는 둘러 싸기 오 차(wraparound error), 앨리애싱(aliasing), 창문영향(window effect)으로 나 눌 수 있는데, 오차는 측정구경의 크기와 마이크로폰 사이의 간격등의 측정 조건 뿐만 아니라 음원의 특성, 홀로그램 평면의 위치 등에 직접적인 영향을 받게 된다. 본 연구에서는 오차해석을 위한 기본 연구로써 점음원(monopole) 과 쌍극자(dipole)음장의 파수 스펙트럼을 해석적으로 구하고 이를 기본으로 평면 음향 홀로그래피 적용시 존재하는 앨리애싱에 대해 고찰하고 전산기 모의 실험 (computer simulation)을 통해 오차를 최소화하는 측정조건을 제 시하고자 한다.

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