• Title/Summary/Keyword: $C^*$ Estimation

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A fast motion estimation method prediction of motion estimation error (움직임 추정오차의 예측을 이용한 고속 움직임 추정 방법)

  • Kang, Hyun-Soo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.9C
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    • pp.1323-1329
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    • 2004
  • This paper presents an enhanced MSEA(multi-level successive elimination algorithm) which is a fast algorithm of the full-search motion estimation. We predict the SAD at the final level using the values of norms at the preceding levels in MSEA and then decide on whether the processing at the following levels should be proceeded or not. We skip the computation at the following levels where the processing is not meaningful anymore. Consequently, we take computational gain. For the purpose of predicting the values of SAD at each level, we first show the theoretical analysis of the value of norm at each level, which is verified by experiments. Based on the analysis a new motion estimation method is proposed and its performance is evaluated.

Decision-directed channel estimation in TETRA system (TETRA 시스템에서 Decision-directed 기법을 이용한 채널 추정 기법)

  • Hwang, Won-Sik;Lee, Yong-Hwan
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.2C
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    • pp.234-241
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    • 2009
  • TETRA Enhanced Data Service (TEDS), which is an upgrade version of narrow-band ETSI TETRA Release 1 system, can support high speed packet data services in frequency selected fading channel. The performance of M-QAM transceivers employed in the TEDS is significantly affected by the accuracy of channel estimation. In this paper, we consider the design of a decision-directed channel estimation scheme robust to fast fading by estimating the channel by means of a per-survivor processing (PSP) method. The performance of the proposed channel estimation scheme is verified by computer simulation.

Angle-of-arrival Estimation fit for an Elliptical Scattering Channel in a Wireless Positioning (무선 위치 인식에서 타원형 산란 채널에 적합한 초광대역 신호 도착 방향 추정)

  • Lee, Yong-Up;Park, Joong-Hoo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.11C
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    • pp.949-954
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    • 2008
  • An ultrawide band (UWB) signal model is proposed to estimate the angle-of-arrivals of the signals arrived in clusters at an UWB receiver for a short-range, high-speed, indoor wireless communication system in an elliptical scattering environment. And a new estimation technique is proposed by modifying the conventional MUSIC algorithm. By using this estimation technique, the estimates of the two unknown parameter sets, angle-of-arrivals and distribution parameters, are obtained with the proposed UWB signal model. The proposed UWB signal model and estimation technique are verified through computer simulations in an ultrawide band communication environment.

OFDM Channel Estimation with Jammed Pilot Excision Method under Narrow-Band Jamming (협대역 재밍환경에서 재밍된 파일럿 제거 방법을 이용한 OFDM시스템의 채널추정에 관한 연구)

  • Han, Myeong-Su;Yu, Tak-Ki;Kim, Ji-Hyung;Kwak, Kyung-Chul;Han, Seung-Youp;Hong, Dae-Sik
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.32 no.2C
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    • pp.166-173
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    • 2007
  • In Orthogonal Frequency Division Multiplexing (OFDM) systems, Narrow-Band Jamming (NBJ) over pilot tones used for channel estimation degrades the system performance. In this paper, we propose a new jammed pilot detection and elimination algorithm to overcome this problem. Moreover, the average Mean-Squared Error (MSE) on one OFDM symbol both under jammed and removed pilot subcarrier is analyzed. And then, the Symbol Error Rate (SER) performance of the channel estimation scheme using the proposed algorithm is evaluated by simulation. We can confirm that the channel estimator with the proposed algorithm improves the channel estimation performance at a high jamming power.

In vitro Estimation of Cardiac Output for the TAH using an Adaptive Fuzzy Identifier

  • Choi, W.W.;Jo, Y.H.;Ahn, J.M.;Park, S.K.;Choi, J.S.;Om, K.S.;Lee, J.J.;Choi, J.H.;Kim, H.C.;Min, B.G.
    • Proceedings of the KOSOMBE Conference
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    • v.1996 no.11
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    • pp.263-267
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    • 1996
  • An estimation algorithm based on training of fuzzy logic system using back-propagation is proposed, in this paper, for determining cardiac output in the TAH. The proposed estimation utilizes only a motor current waveform generated from the moving actuator of the electromechanical TAH without using any extra transducers as an information source for estimation. In in vitro tests, the resultant estimation performance was acceptable to alppy the proposed algorithm to animal experiments and further clinical applications.

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Estimation of Pasture Production and Nutritive Vallue in Relation to Plant Heigth of Orchardgrass (Dactylis glomerata L. ) (Orchargrass 우점초지에서 초장에 의한 생산량과 사료가치 추정)

  • Park, Moon-Soo;Seo, Sung;Kim, Ha-Jong
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.11 no.3
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    • pp.169-174
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    • 1991
  • For simple estimation of pasture production and nutritive value in relation to height of orchardgrass (Ductylis glomumtu L.), the experiment was carried out in a pasture mixture dominated by orchardgrass. The samples of grasses were harvested at the heights of about 30, 40, 50, 70 and 90 cm at the first harvest under different percentage of 100 (grass coverage): 0 (bareland), 80 : 20, 60 : 40, 40 : 60 and 20 : 80, respectively. As the height of orchardgrass was increased, fresh and dry matter (DM) yield were significantly increased. The regression equation between DM yield (Y) and height (X) was Y=ll. 5390 X- 146.60 (r=O. 9414 * * ). Also the higher bareland, the lower pasture production was observed. As the plant height at the first harvest was increased, the contents of crude (C) protein, C. fat, C. ash and relative feed value were markedly decreased. On the other hand, the contents of C. fiber, NFE, NDF. ADF, cellulose and lignin were significantly increased, respectively. The higher height, the lower DM digestibility was found. The equation between digestibility (Y) and height (X) was Y=- 0.2193 X+ 80.99 (r = - 0.9862**). Considering DM yield, digestibility and crude protein, the optimum height of orchardgrass at the first harvest was 59 to 67crn for better pasture production and nutritive value.

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Modeling and Characteristic Analysis of HEV Li-ion Battery Using Recursive Least Square Estimation (최소 자승법을 이용한 하이브리드용 리튬이온 배터리 모델링 및 특성분석)

  • Kim, Ho-Gi;Heo, Sang-Jin;Kang, Gu-Bae
    • Transactions of the Korean Society of Automotive Engineers
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    • v.17 no.1
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    • pp.130-136
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    • 2009
  • A lumped parameter model of Li-ion battery in hybrid electric vehicle(HEV) is constructed and system parameters are identified by using recursive least square estimation for different C-rates, SOCs and temperatures. The system characteristics of pole and zero in frequency domain are analyzed with the parameters obtained from different conditions. The parameterized model of Li-ion battery indicates highly dependant of temperatures. The system pole and internal resistance changes 6.6 and 18 times at $-20^{\circ}C$, comparing with those at $25^{\circ}C$, respectively. These results will be utilized on constructing model-based state observer or an on-line identification and an adaptation of the model parameters in battery management systems for hybrid electric vehicle applications.

Storage Life Estimation of Next Infrared Flare Material (차기 적외선 섬광제 저장수명 예측)

  • Back, Seungjun;Son, Youngkap;Kim, Namjin;Kwon, Taesoo
    • Journal of the Korea Institute of Military Science and Technology
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    • v.19 no.3
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    • pp.311-318
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    • 2016
  • This paper shows storage life estimation of next IR(infrared) flare material through accelerated degradation tests. Three temperature conditions for the accelerated degradation tests are 55, 65 and $75^{\circ}C$. Six performances of IR flare material are burning time, IR peak/continuous Intensity, total energy of near/mid-IR and color ratio, and they were measured after the tests. Storage life of the IR flare material was estimated through both analyzing the degradation data of those performances and applying distribution-based degradation models to the data. Over 30 years of storage life at $20^{\circ}C$ is estimated in terms of IR peak intensity with reliability 0.99 and confidence level 99 %. Additionally, 10 years of storage period at $21^{\circ}C$ would be equivalent to 68 days of accelerated test at $65^{\circ}C$ from the activation energy in Arrhenius model.

Estimation of Measurement Uncertainty in Vitamin C Analysis from Vegetable and Fruit Juice (야채음료 중 비타민 C 분석에 있어서의 측정불확도 추정)

  • Kim, Young-Jun;Kim, Hyeon-Wee
    • Korean Journal of Food Science and Technology
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    • v.35 no.6
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    • pp.1053-1059
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    • 2003
  • This study aimed to determine the amount of vitamin C from vegetable & fruit juice by high performance liquid chromatograhy (HPLC). Components for estimation of measurement uncertainty associated with the analysis of vitamin C, such as standard weight, purity, molecular weight, dilution of standard solution, calibration curve, recovery, and precision, were importantly applied. The estimation of uncertainty obtained with systematic and random error based on the GUM (Guide to the expression of uncertainty in measurement) and EURACHEM document with mathematical calculation and statistical analysis. The components, evaluated ty either Type A or Type B methods, were combined to produce an overall value of uncertainty known as the combined standard uncertainty. An expanded uncertainty was obtained by multiplying the combined standard uncertainty with a coverage factor (k) calculated from the effective degree of freedom. The content of vitamin C from vegetable and fruit juice was 27.53 mg/100g and the expanded uncertainty by multiplying by the coverage factor (k, 2.06) was 0.63 mg/100g at a 95% confidence level. It was concluded that the main sources were, in order of recovery and precision, weight and purity of the reference material, dilution of the standard solution, and calibration curve. Careful experiments on other higher uncertainties is further needed in addition to better personal proficiency in sample analysis in terms of accuracy and precision.

Theoretical Basis of PERT Formula and a New Estimation Method (PERT 공식의 이론적 근거와 새로운 추정방법)

  • Kim, Se-Hun;Won, Y.K.;Chae, Kyung-C.
    • Journal of Korean Institute of Industrial Engineers
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    • v.15 no.2
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    • pp.103-108
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    • 1989
  • PERT formulae for the mean and variance of activity time are near exact only over a short interval of the concentration parameter which is defined as the sum of the two shape parameters of the beta distribution. Aiming a better estimation of the mean and variance of activity time, we propose a method of subjectively estimating this concentration parameter via estimating the probability of completing the activity within a specified time interval.

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