• Title/Summary/Keyword: time like

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Face Detection and Tracking using Skin Color Information and Haar-Like Features in Real-Time Video (실시간 영상에서 피부색상 정보와 Haar-Like Feature를 이용한 얼굴 검출 및 추적)

  • Kim, Dong-Hyeon;Im, Jae-Hyun;Kim, Dae-Hee;Kim, Tae-Kyung;Paik, Joon-Ki
    • 한국HCI학회:학술대회논문집
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    • 2009.02a
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    • pp.146-149
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    • 2009
  • Face detection and recognition in real-time video constitutes one of the recent topics in the field of computer vision. In this paper, we propose face detection and tracking algorithm using the skin color and haar-like feature in real-time video sequence. The proposed algorithm further includes color space to enhance the result using haar-like feature and skin color. Experiment results reveal the real-time video processing speed and improvement in the rate of tracking.

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SPACE-LIKE COMPLEX SUBMANIFOLDS OF AN INDEFINITE K HLER MANIFOLD

  • Kwon, Jung-Hwan;Pyo, Yong-Soo;Shin, Kyoung-Hwa
    • Journal of the Korean Mathematical Society
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    • v.36 no.6
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    • pp.1145-1168
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    • 1999
  • The purpose of this paper is to study the complete submanifolds with restricted space-like and time-like holomorphic bisectional curvatures in an indefinite locally symmetric K hler manifold.

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Design of High-performance Pedestrian and Vehicle Detection Circuit using Haar-like Features (Haar-like 특징을 이용한 고성능 보행자 및 차량 인식 회로 설계)

  • Kim, Soo-Jin;Park, Sang-Kyun;Lee, Seon-Young;Cho, Kyeong-Soon
    • The KIPS Transactions:PartA
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    • v.19A no.4
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    • pp.175-180
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    • 2012
  • This paper describes the design of high-performance pedestrian and vehicle detection circuit using the Haar-like features. The proposed circuit uses a sliding window for every image frame in order to extract Haar-like features and to detect pedestrians and vehicles. A total of 200 Haar-like features per sliding window is extracted from Haar-like feature extraction circuit and the extracted features are provided to AdaBoost classifier circuit. In order to increase the processing speed, the proposed circuit adopts the parallel architecture and it can process two sliding windows at the same time. We described the proposed high-performance pedestrian and vehicle detection circuit using Verilog HDL and synthesized the gate-level circuit using the 130nm standard cell library. The synthesized circuit consists of 1,388,260 gates and its maximum operating frequency is 203MHz. Since the proposed circuit processes about 47.8 $640{\times}480$ image frames per second, it can be used to provide the real-time detection of pedestrians and vehicles.

Eigenvalue Assignment for Linear Time-Varying Systems via Ackermann-like Formula (선형 시변 시스템의 고유치 지정을 위한 Ackermann형 공식)

  • 이호철;최재원
    • Journal of Institute of Control, Robotics and Systems
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    • v.9 no.3
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    • pp.186-195
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    • 2003
  • This paper deals with eigenvalue assignment techniques for linear time-varying systems as a way of achieving feedback stabilization. For this, the novel eigenvalue concepts, which are the time-varying counterparts of the conventional (time-invariant) eigenvalue notions, are introduced. Then, the Ackermann-like formulae for SISO/MIMO linear time-varying systems are proposed. It is believed that these techniques are the generalized versions of the Ackermann formulae for linear time-invariant systems. The advantages of the proposed Ackermann-like formulae are that they neither require the transformation of the original system into the phase-variable form nor compute the eigenvalues of the original system. Two examples are given to demonstrate the capabilities of the proposed techniques.

Effective time-frequency characterization of Lamb wave dispersion in plate-like structures with non-reflecting boundaries

  • Wang, Zijian;Qiao, Pizhong;Shi, Binkai
    • Smart Structures and Systems
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    • v.21 no.2
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    • pp.195-205
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    • 2018
  • Research on Lamb wave-based damage identification in plate-like structures depends on precise knowledge of dispersive wave velocity. However, boundary reflections with the same frequency of interest and greater amplitude contaminate direct waves and thus compromise measurement of Lamb wave dispersion in different materials. In this study, non-reflecting boundaries were proposed in both numerical and experimental cases to facilitate time-frequency characterization of Lamb wave dispersion. First, the Lamb wave equations in isotropic and laminated materials were analytically solved. Second, the non-reflecting boundaries were used as a series of frames with gradually increased damping coefficients in finite element models to absorb waves at boundaries while avoiding wave reflections due to abrupt property changes of each frame. Third, damping clay was sealed at plate edges to reduce the boundary reflection in experimental test. Finally, the direct waves were subjected to the slant-stack and short-time Fourier transformations to calculate the dispersion curves of phase and group velocities, respectively. Both the numerical and experimental results suggest that the boundary reflections are effectively alleviated, and the dispersion curves generated by the time-frequency analysis are consistent with the analytical solutions, demonstrating that the combination of non-reflecting boundary and time-frequency analysis is a feasible and reliable scheme for characterizing Lamb wave dispersion in plate-like structures.

Seismic analysis of steel structure with brace configuration using topology optimization

  • Qiao, Shengfang;Han, Xiaolei;Zhou, Kemin;Ji, Jing
    • Steel and Composite Structures
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    • v.21 no.3
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    • pp.501-515
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    • 2016
  • Seismic analysis for steel frame structure with brace configuration using topology optimization based on truss-like material model is studied. The initial design domain for topology optimization is determined according to original steel frame structure and filled with truss-like members. Hence the initial truss-like continuum is established. The densities and orientation of truss-like members at any point are taken as design variables in finite element analysis. The topology optimization problem of least-weight truss-like continuum with stress constraints is solved. The orientations and densities of members in truss-like continuum are optimized and updated by fully-stressed criterion in every iteration. The optimized truss-like continuum is founded after finite element analysis is finished. The optimal bracing system is established based on optimized truss-like continuum without numerical instability. Seismic performance for steel frame structures is derived using dynamic time-history analysis. A numerical example shows the advantage for frame structures with brace configuration using topology optimization in seismic performance.

The Mechanical Properties of Fluffy Spun-like Yarn by ATY Textured (1) (ATY 사가공에 의한 Fluffy Spun-like Yarn의 물성 (1))

  • Park, Myung Soo
    • Textile Coloration and Finishing
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    • v.25 no.3
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    • pp.223-231
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    • 2013
  • This research has a main focus on providing fundamental data for on-the-spot industrial fields by comparing and contrasting physical properties of fluffy spun-like material. The fluffy spun-like yarn is developed as fluffy yarn similar to natural spun-like yarn by treating polyester(FDY and + type shaped DTY) with ATY machine. In this experiment, using ATY machine for raw material texturing, we produced two fluffy yarns: (i) + type shaped(50d/36f, DTY) as core yarn and 100d/192f FDY as effect yarn[ATY(D)], (ii) FDY(75/36) as core yarn and 100d/192f FDY [ATY(F)] as effect yarn. After producing thous yarns, we twisted them with 500T/M, 700T/M, 1000T/M, respectively. produced yarns through this process were used as the samples for this experiment. Even though the shrinkage of fluffy yarn ATY(F) and ATY(D) becomes high as treated temperature rises and treated time lengthens, it is more affected by treated temperature then by treated time. In this experiment, produced fluffy yarn[ATY(D)] shows a little high values for temperature, but almost same values for higher temperatures. When we compare ATY(F) with ATY(D) fluffy yarn shows more natural fluffy yarn surface structure like natural cotton. The shrinkage of 700T/M twisted ATY(D) fluffy yarn show about 11% under treated temperature $180^{\circ}C$ and treated time 30min, and about 7% under $120^{\circ}C$ and 30min, respectively. But the shrinkage of 1000T/M fluffy yarn shoes about 9% and 6% under same conditions. Regarding treated time, tenacity and initial modulus of ATY(D) fluffy yarn rise high until 30min, but do not show much increase above 30min. Regarding treated temperature, tenacity and initial modulus of it rise high aboyer $140^{\circ}C$.

Stabilizing Controller Design for Linear Time-Varying Systems Using Ackerman-like Formula

  • Choi, Jae-Weon;Lee, Ho-Chul
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.125.1-125
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    • 2001
  • This paper deals with the eigenvalue assignment technique for linear time-varying systems to achieve feedback stabilization. For this, we introduce the novel eigenvalue concepts. Then, we propose the Ackerman-like formula for linear time-varying systems. It is believed that this technique is the generalized version of the Ackerman formula forlinear time-invariant systems. The advantages of the proposed technique are that it does not require the transformation of the original system into the phase-variable form nor the computation of eigenvalues of the original system.

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The Impact of Information Lead Time Improvement on the Distributed Supply Chain System (분산형 공급체인에서 단계별 정보지연 개선이 주는 효과)

  • 김철수;최근영
    • The Journal of Information Systems
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    • v.10 no.2
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    • pp.129-150
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    • 2001
  • In this study, we model a decentralized supply chain system which is managed by four types of centers, sequentially located: Retailer, Wholesaler, Distributor, and Factory Each center contributes to enhancing the performance of the supply chain system individually with its own local inventory information. Through experiments which are performed with a programmed simulation (like the MIT beer game), we investigate how the information lead time improvement in each center affects the whole system. And we show that the impact of the lead time improvement in the downstream, like retailers, affects more to the system than the one in the upstream, like factories, in a cost-effective way. Moreover, by using information lead time for each center, we analyze how much the extent of the improvement affects the whole system, especially for the total cost and the order level.

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Real-Time face detection using the Skin color and Haar-like feature (피부색과 Haar-like feature를 이용한 실시간 얼굴검출)

  • Jeong, Joong-Gyo;Park, Sang-Sung;Jang, Dong-Sik
    • Journal of the Korea Society of Computer and Information
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    • v.10 no.4 s.36
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    • pp.113-121
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    • 2005
  • Face detection in real-time video constitutes one of the major trend in face recognition. In this paper, we propose a face detection algorithm using the skin color and Haar-like feature in real-time video. The proposed algorithm is followed by three sequences; First, moving objects are detected by difference-method in YCbCr coordinates, and then by using Haar-like features, face candidate regions of the moving objects is selected. Finally we extract the most possible face candidates by comparing the pixel values of face candidates with the skin color. In order to prevent a mistake. we use similar features or skin color to detect a face by selecting a adaptive ROI and improve the processing speed in real-time video. The computer simulation shows the validity of the proposed method that the processing speed is improved by 30% than previous works and the detection success rate is 96.8%.

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