• Title/Summary/Keyword: Local feature

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A Research on BCI using Coherence between EEG and EMG (EEG와 EMG의 Coherence을 이용한 BCI 연구)

  • Kim, Young-Joo;Whang, Min-Cheol;Kang, Hee
    • Journal of the Ergonomics Society of Korea
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    • v.27 no.2
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    • pp.9-14
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    • 2008
  • Coherence can be used to evaluate the functional cortical connections between the motor cortex and muscle. This study is to find coherence between EEG (electroencephalogram) and EMG (electromyogram) evoked by movement of a hand. Seven healthy participants were asked to perform thirty repetitive movement of right hand for ten seconds with rest for ten seconds. Specific feature of EEG components has been extracted by ICA (independent component analysis) and coherence between EEG and EMG was analyzed from data measured EEG in five local areas around central part of head and EMG in flexer carpri radialis muscle during grabbing movement. Coherence between EEG and EMG was successfully obtained at 0.025 confidence limit during hand movement and showed significant difference between rest and movement at 13-18Hz.

Robust Speech Hash Function

  • Chen, Ning;Wan, Wanggen
    • ETRI Journal
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    • v.32 no.2
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    • pp.345-347
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    • 2010
  • In this letter, we present a new speech hash function based on the non-negative matrix factorization (NMF) of linear prediction coefficients (LPCs). First, linear prediction analysis is applied to the speech to obtain its LPCs, which represent the frequency shaping attributes of the vocal tract. Then, the NMF is performed on the LPCs to capture the speech's local feature, which is then used for hash vector generation. Experimental results demonstrate the effectiveness of the proposed hash function in terms of discrimination and robustness against various types of content preserving signal processing manipulations.

Adaptive Channel Normalization Based on Infomax Algorithm for Robust Speech Recognition

  • Jung, Ho-Young
    • ETRI Journal
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    • v.29 no.3
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    • pp.300-304
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    • 2007
  • This paper proposes a new data-driven method for high-pass approaches, which suppresses slow-varying noise components. Conventional high-pass approaches are based on the idea of decorrelating the feature vector sequence, and are trying for adaptability to various conditions. The proposed method is based on temporal local decorrelation using the information-maximization theory for each utterance. This is performed on an utterance-by-utterance basis, which provides an adaptive channel normalization filter for each condition. The performance of the proposed method is evaluated by isolated-word recognition experiments with channel distortion. Experimental results show that the proposed method yields outstanding improvement for channel-distorted speech recognition.

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ZOOMING FUNCTIONAL METHOD FOR POSITION MEASUREMENT IN ENCLOSING SIGNAL FIELD BASED N CONCEPT OF PROGRESSIVE LEARNING MEASUREMENT SYSTEM

  • Ohyama, Shinji;Cao, Li;Kobayashi, Akira
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.1318-1321
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    • 1997
  • A method for two-dimensional position measurement using an enclosing field has been studied and reported. The feature of this mehtod is zooming functional measurement by operating both the initial phase shift and the brightness ratio of the lighting function. An experimental system was developed and the experimental results on zooming effects are shown in this paper. This system is also an example of a "progressive learning measurement system".tem".uot;.

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Motion Analysis with Time Delay Neural Network (시간 지연 신경망을 이용한 동작 분석)

  • Jang, Dong-Sik;Lee, Man-Hee;Lee, Jong-Won
    • Journal of Institute of Control, Robotics and Systems
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    • v.5 no.4
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    • pp.419-426
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    • 1999
  • A novel motion analysis system is presented in this paper. The proposed system is inspired by processing functions observed in the fly visual system, which detects changes in input light intensities, determines motion on both the local and the wide-field levels. The system has several differences from conventional motion analysis system. First, conventional systems usually focused on matching similar feature or optical flow, but neural network is applied in this system. Back propagation is used by learning method, and Tine Delay Neural Network (TDNN) is also used as analysis method. Second, while conventional systems usually limited on only two frames of sequence, the proposed system accept multiple frames of sequence. The experimental results showed a 94.7% correct rate with a speed of 71.47 milli seconds for real and synthetic images.

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A Study for Global Optimization Using Dynamic Encoding Algorithm for Searches

  • Kim, Nam-Geun;Kim, Jong-Wook;Kim, Sang-Woo
    • 제어로봇시스템학회:학술대회논문집
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    • 2004.08a
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    • pp.857-862
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    • 2004
  • This paper analyzes properties of the recently developed nonlinear optimization method, Dynamic Encoding Algorithm for Searches (DEAS) [1]. DEAS locates local minima with binary strings (or binary matrices for multi-dimensional problems) by iterating the two operators; bisectional search (BSS) and unidirectional search (UDS). BSS increases binary strings by one digit (i.e., zero or one), while UDS performs increment or decrement to binary strings with no change of string length. Owing to these search routines, DEAS retains the optimization capability that combines the special features of several conventional optimization methods. In this paper, a special feature of BSS and UDS in DEAS is analyzed. In addition, a effective global search strategy is established by using information of DEAS. Effectiveness of the proposed global search strategy is validated through the well-known benchmark functions.

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Behavior of Stress Corrosion Cracking in Structural Steel under Acid Fog Environment (산성안개하에서 기계·구조용강의 응력부식균열 거동)

  • Lim, Yong Ho;Kim, Min-Gun
    • Journal of Industrial Technology
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    • v.17
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    • pp.291-295
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    • 1997
  • The tests of stress corrosion cracking in structural carbon steel were carried out under the conditions of acid fog and general water. As the result of measurement SCC rupture time under acid fog was observed to be much shorter than that of general water at the same stress level. Therefore, acid fog drops the SCC strength in structural carbon steel due to strong corrosion. In the SCC process by acid fog, crack initiation was caused by pit corrosion and local stress concentration, and distinctive feature of crack growth shows branching since crack grows to the corrosion direction. Moreover, corrosion products were observed by clevage corrosion on the crack surfaces.

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A Heuristic Approach for an Layout and Sizing of an Ejector Pin (사출 금형의 밀핀 설계를 위한 경험적 설계 접근법)

  • 이희성;변철웅;이수홍
    • Korean Journal of Computational Design and Engineering
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    • v.9 no.2
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    • pp.112-121
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    • 2004
  • As customers demands are rapidly changing, a product life cycle is getting shorter and a product model is forced to be changed frequently. An ejecting design system becomes more important for high productivity to eject a product in high temperature without any damage. For example, an ejector pin that is a key component of the system can cause high local stresses and strains in the molding at the time of ejection. The number, the size, and the location of pins are important to make a smooth ejection. Therefore we propose an analytical approach with the aid of designer’s experience to calculate a total release force and pressure distribution so that the number, the size, and the location of pins can be easily determined. As a part of the result, the design system is built by Intent! with AutoCAD 2000 and a video player deck example is presented to verify the approach.

A Basic Study on the Landscape Morphogenesis of Major Local towns (Do-Eup) in Korea(I) (우리나라 도읍경관 변천과정의 기초연구(I))

  • 박찬룡;김한배
    • Journal of the Korean Institute of Landscape Architecture
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    • v.15 no.2
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    • pp.101-113
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    • 1987
  • The landscape structure of the both pre-industrial and industrial cities should be influenced to the topographical feature , religious thoughts, political ruling system and history. In the major socio-cultural factors in the pre-industrial townscapes in korea, the Feng - Shui(poongsu) which is an acient human settlement organization system based on the “Yin - Yang” principle and “Five Elements” and “Chryaegogong”system were the most important factors to the formation of traditional town scape in Korea. The landscape during the Japanese colonial periods were basically reorganized through change of “Boundary”, “Center” “Direction(path)” and “Domain” which were expressed by distinct traditional townscape in Yi dynasty. The physical shapes, meanings and behaviors of townscape were expressed properly of the intention of the colonization. As changes to the mordern industrial cities, the townscape had been amended landscape elements of the Japanese imperialism to an ideology of rebirth nation. Also as changes to the modern industrial cities, “Boundary”, “Center”, and “Domain” spreaded into the suburbs by funtionalsm and these were expressed an incoherent value system which were the advancement of growth, pursuit policies as well as an advancement of science techniques.

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Speed Estimation of a Mobile Station Using the Undecimated Discrete Wavelet Transform (웨이블릿을 이용한 속도 측정)

  • Lee, Chang-Soo;Song, Hun-Guen;Yoo, Kyung-Yul
    • Proceedings of the IEEK Conference
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    • 2001.09a
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    • pp.841-844
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    • 2001
  • This paper introduces a new technique for estimating the speed of a mobile station in a wireless system. The proposed method is based on the feature extraction of the received signal envelope. The undecimated discrete wavelet transform via lifting captures local minimum points of the received signal, which is used for the speed estimation. This technique requires neither knowledge of the average received power of the nonstationary signal nor adaptation of a temporal observation window, in contrast to other speed estimators given in the literature. Simulations show that the proposed speed estimator tracks the variable speed of the mobile station.

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