• Title/Summary/Keyword: Short-distance

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Architecture of Signal Processing Unit to Improve Range and Velocity Error for Automotive FMCW Radar (FMCW 레이더의 거리 및 속도 오차 향상을 위한 신호처리부 하드웨어 구조 제안)

  • Hyun, Eu-Gin;Lee, Jong-Hun
    • Transactions of the Korean Society of Automotive Engineers
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    • v.18 no.4
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    • pp.54-61
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    • 2010
  • In this paper, we design the signal processing unit to effectively support the proposed algorithm for an automotive Frequency Modulation Continuous Wave(FMCW) radar. In the proposed method, we can obtain the distance and velocity with improved error depending on each range(long, middle, and short) of the target. Since a high computational capacity is required to obtain more accurate distance and velocity for target in near range, the proposed signal processing unit employs the time de-interleaving and the frequency interpolation method to overcome the limitation. Moreover, for real-time signal processing, the parallel architecture is used to extract simultaneously the distance and velocity in each range.

Air Quality Impact Analysis of Point and Area Sources (점오염원과 면오염원의 대기환경영향 분석)

  • 김영성;손재익
    • Journal of Korean Society for Atmospheric Environment
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    • v.9 no.2
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    • pp.168-173
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    • 1993
  • Air quality impacts of point and area sources were analyzed by using ISCST2 with wind speed and stability class combinations of SCREEN. Stack height was important in determining the impact of point sources. With the stack height reduced to 21m from 75m, the concentration in the vicinity increased several times in spite of decreasing the emission rate by half. When the emission rates were same, concentrations from an area source of 10m release height were slightly lower than those from a point source of 21m stack height at the plume centerline. Bur the area source resulted in larger area of high concentration. Concentration from the point source was high in neutral to slightly unstable conditions with strong winds in a short distance, and in stable conditions with weak winds in a long distance. Concentration from the area source decreased with distance from the source, and was high in stable conditions with weak winds.

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Study on the Spraying Parameters of a Plasma-sprayed Hydroxyapatite Coating (플라즈마 용사법에 의한 Hydroxyapatite 코팅의 용사조건에 관한 연구)

  • 여인웅;안효석
    • Journal of the Korean Ceramic Society
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    • v.36 no.4
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    • pp.444-450
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    • 1999
  • Hydroxyapatite(HA) was spray-coated to alloy substrate(Ti-6Al-4V) using plasma-spray process for bioceramic application The coating morphology composition and crystallinity were influenced by following process parameters ; stand-off distance spray power level and auxiliary gas pressure. These parameters have been systematically varied in the present study to evaluate their relative influence on the coating qual-ity and to seek an optimum spraying condition. Amorphicity and decomposition of HA increased with stand-off distance and the imperfect coating layer was obtained at the short stant-off distance (55mm). The cry-stallinity of HA coating decreased with spray power level and auxiliary gas pressure but the bond strength between the HA coated layer and Ti alloy substrate increased with the spray power level.

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A study on the Multipurpose Usage of Incheon International Airport Railway - Focusing on the Improvement of Connecting Systems - (인천국제공항철도의 다목적 활용방안 - 연계체계 개선을 중심으로)

  • Park Jeong-Soo;Won Jai-Mu;Han Woo-Jin
    • Journal of the Korean Society for Railway
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    • v.8 no.6 s.31
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    • pp.610-616
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    • 2005
  • The Incheon International Airport Express(I'Rex) is the railroad that connects Incheon International Airport, Gimpo Airport and Seoul Station. I'Rex is now under construction, and it will be connected to Gimpo Airport by 2007, to Seoul Station by 2010. However, there has been no discussion on how th connect different routes of railway Systems. Therefore it seems likely that rail passenger demand will be lower than that of limousine bus. Therefor, this paper proposes 4 effective connecting methods for I'Rex - (1) Shuttle transport, (2) Short-distance connecting transport (Inside I'Rex, Seoul Subway Line 9, 'Han-River line') (3) Mid-distance connecting transport (Jung-ang, Tae-baek, Young-dong line) (4) Long-distance connecting transport (Korean Train Express (Korean high speed railroad)) These methods can increase the connectivity of I'Rex with existing railroads and the competition power of I'Rex against a highway.

Effective Connecting Methods Between Incheon International Airport Railroad and Existing Railroads (인천국제공항철도와 기존 철도의 효율적인 연계방안)

  • 한우진
    • Proceedings of the KSR Conference
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    • 2002.10a
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    • pp.253-258
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    • 2002
  • The Incheon International Amort Railroad (IIAR) is the railroad that connects Incheon International Airport, Gimpo Airport and Seoul Station. IIAR is now under construction, and it will be finished to Gimpo Amort by 2006, to Seoul Station by 2008. But IIAR is not only so late to start but also has no discussion about effective connecting methods to existing railroads and fine operation plan. Therefore, after IIAR opens, it is possible for IIAR to lose to limousine bus using highway. So, this paper proposes 4 effective connecting methods for IIAR - (1) Shuttle transport, (2) Short-distance connecting transport (Inside IIAR, Seoul Subway Line 9, 'Han-River line') (3) Mid-distance connecting transport (Jung-ang, Tae-baek, Young-dong line) (4) Long-distance connecting transport (Korean Train express (korean high speed railroad)) These methods can increase the connectivity of IIAR with existing railroads and the competition power of IIAR against highway.

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A New Distance Relaying Algorithm Immune to Mutual Coupling Effect and Reactance Effect for 765kV Untransposed Parallel Transmission Lines (상호결합효과와 리액턴스효과를 제거한 765kV 비연가 송전선로 보호용 거리계전 알고리즘)

  • Ahn Yong-Jin;Kang Sang-Hee
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.54 no.1
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    • pp.25-30
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    • 2005
  • An accurate digital distance relaying algorithm which is immune to mutual coupling effect and reactance effect of the fault resistance and the load current for the line faults in 765kV untransposed transmission lines is proposed. The algorithm can estimate adaptively the impedance to a fault point independent of the fault resistance. To compensate the magnitude and phase of the apparent impedance, this algorithm uses the angle of an impedance deviation vector. The impedance correction algorithm for phase-to-ground fault and phase-to-phase short fault use a voltage equation at fault point to compensate the fault current at fault point. A series of tests using EMTP output data in a 765kV untransposed transmission lines have proved the accuracy and effectiveness of the proposed algorithm.

Kinematical Differences of the Male Professional Golfers' 30 Yard Chip Shot and Pitch Shot Motion (남자프로골퍼의 30 야드 칩샷과 피치샷 동작의 운동학적 차이)

  • Pyun, Eun-Kyung;Park, Young-Hoon;Youm, Chang-Hong;Sun, Sheng;Seo, Kuk-Woong;Seo, Kook-Eun
    • Korean Journal of Applied Biomechanics
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    • v.17 no.2
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    • pp.177-185
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    • 2007
  • Even though there were no clear definitions of the short game and short game distance, short game capability is crucial for a good golf score. Generally, chip shot and pitch shot are regarded as two principal components of the short game. Chip shot is a short, low trajectory shot played to the green or from trouble back into play. Pitch shot is a high trajectory shot of short length. Biomechanical studies were conducted usually to analyze full swing and putting motions. The purpose of the study was to reveal the kinematical differences between professional golfers' 30 yard $53^{\circ}wedge$ chip shot and $56^{\circ}wedge$ pitch shot motions. Fifteen male professional golfers were recruited for the study. Kinematical data were collected by the 60 Hz three-dimensional motion analysis system. Statistical comparisons were made by paired t-test, ANOVA, and Duncan of the SPSS 12.0K with the $\alpha$ value of .05. Results show that both the left hand and the ball were placed left of the center of the left and right foot at address. The left hand position of the chip shot was significantly left side of that of the pitch shot. But the ball position of the pitch shot was significantly right side of that of the chip shot. All body segments aligned to the left of the target line, open, at address. Except shoulder, there were no significant pelvis, knee, and feet alignment differences between chip shot and pitch shot. These differences at address seem for the ball height control. Pitch shot swing motions(the shoulder and pelvis rotation and the club head travel distance) were significantly bigger than those of the chip shot. Club head velocity of the pitch shot was significantly faster than that of the chip shot at the moment of impact. This was for the same shot length control with different lofted clubs. Swing motion differences seem mainly caused by the same shot length control with different ball height control.

Developing Takagi-Sugeno Fuzzy Model-Based Estimator for Short-Term Load Forecasting (단기부하예측을 위한 Tskagi-Sugeno 퍼지 모델 기반 예측기 설계)

  • 김도완;박진배;장권규;정근호;주영훈
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2004.04a
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    • pp.523-527
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    • 2004
  • This paper presents a new design methods of the short-term load forecasting system (STLFS) using the data mining. The proposed predictor takes form of the convex combination of the linear time series predictors for each inputs. The problem of estimating the consequent parameters is formulated by the convex optimization problem, which is to minimize the norm distance between the real load and the output of the linear time series estimator, The problem of estimating the premise parameters is to find the parameter value minimizing the error between the real load and the overall output. Finally, to show the feasibility of the proposed method, this paper provides the short-term load forecasting example.

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Short-range Visible Light Positioning Based on Angle of Arrival for Smart Indoor Service

  • Lee, Yong Up;Park, Seop Hyeong
    • Journal of Electrical Engineering and Technology
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    • v.13 no.3
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    • pp.1363-1370
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    • 2018
  • In visible light (VL) positioning based on angle of arrival (AOA) estimation for smart indoor service, the AOA parameters obtained at the receiver has sometimes a random and distributed angle form instead of a point angle form due to the multipath transfer of the actual visible light and short positioning distance. The AOA estimation of a VL signal with a random and parametric distributed angle form may give incorrect AOA parameter estimates, which may result in poor VL positioning performance. In this paper, we classify the AOA parameters of the received VL signal into three forms according to the actual positioning channel environment and consider the short-range VL positioning method. We propose a subspace-based AOA parameter estimation technique and a data fusion method, and analyzed the proposed method by simulation and the measurement of the real VL channel characteristics.