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Use of Support Vector Regression in Stable Trajectory Generation for Walking Humanoid Robots

  • Kim, Dong-Won;Seo, Sam-Jun;De Silva, Clarence W.;Park, Gwi-Tae
    • ETRI Journal
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    • v.31 no.5
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    • pp.565-575
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    • 2009
  • This paper concerns the use of support vector regression (SVR), which is based on the kernel method for learning from examples, in identification of walking robots. To handle complex dynamics in humanoid robot and realize stable walking, this paper develops and implements two types of reference natural motions for a humanoid, namely, walking trajectories on a flat floor and on an ascending slope. Next, SVR is applied to model stable walking motions by considering these actual motions. Three kinds of kernels, namely, linear, polynomial, and radial basis function (RBF), are considered, and the results from these kernels are compared and evaluated. The results show that the SVR approach works well, and SVR with the RBF kernel function provides the best performance. Plus, it can be effectively applied to model and control a practical biped walking robot.

The Trend and Problems of Korean e-Business Technology Policy (e-비즈니스 기술 정책의 추세와 문제점)

  • Park, Gyeong-Hye
    • 한국디지털정책학회:학술대회논문집
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    • 2005.06a
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    • pp.463-474
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    • 2005
  • There are many challenges to solve on how we will use IT infrastructures accepted as the best worldwide level for strength of country's competitiveness. Over the past years, IT environment has been formed to expand the basis of e-Business by policy, but little contributed to management efficiency such as improvement of business productivity through utilization of it. This paper explores the category of the related technology policies by classifying e-Business technologies and presents the problems and developmental directions for those policies by investigating the trends of the policies which have been framed so far. Especially, this article also examines the differences between the technology policy on the road map of 2010 e-Business policy and the IT839 strategy.

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In-situ Determination of Absorption Coefficients in a Room

  • Suh, Jin-Sung
    • The Journal of the Acoustical Society of Korea
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    • v.20 no.3E
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    • pp.10-17
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    • 2001
  • The possibility is investigated of determining the diffuse absorption coefficients of the wall surfaces in a real room by minimizing the errors between the measured energy impulse response of a real room and the predicted energy impulse responses obtained from the ray tracing simulation of the room. In other words, this can possibly serve as a basis for "acoustical system identification" in attempting to determine the "best fit" of modelled absorption coefficients to measured energy response data. Algorithms for attempting this were investigated. The algorithms developed for this purpose proved to be rigorous and efficient. Instead of using the ray tracing model to determine the absorption coefficients, the phase image model was used in order to determine the acoustic impedances of wall surfaces. However, the numerical algorithms could not find the correct impedance values, primarily due to the wide range of the acoustic impedance values of any single acoustic material and very long computation time.

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An Expert System for Optimal Network Reconfiguration in Distribution Systems (배전계통의 최적 회로재구성을 위한 전문가 시스템)

  • Yoon, Yong-Han;Kim, Jae-Chul;Jang, Jeong-Tae
    • Proceedings of the KIEE Conference
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    • 1991.11a
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    • pp.71-74
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    • 1991
  • This paper is described an expert system which performs the network reconfiguration in order to operate distribution systems optimally using heuristic rules. The proposed network reconfiguration is able to not only eliminate abnormal states such as overload of transformers/lines and low voltage violation, but also achieve minimum power loss and optimum load balancing under normal states. In order to apply the network reconfiguration efficiently, an expert system is adopted a best-first tree searching strategy on the basis of heuristics, and is implemented in AI language Turbo PROLOG. Several examples are used to illustrate concepts described above.

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Efficiency Optimization Control of Induction Motor System using Fuzzy Control (퍼지제어를 이용한 유도전동기 시스템의 효율 최적화 제어)

  • Chung, Dong-Hwa;Park, Gi-Tae;Lee, Hong-Gyun
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.50 no.7
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    • pp.318-324
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    • 2001
  • Efficiency optimization of an indirect vector controlled induction motor drive is proposed. The loss models are used in the validation of the fuzzy logic based on-line efficiency optimization control. At steady state, the fuzzy controller adaptively changes the excitation current on the basis of measured input power, until the maximum efficiency point is reached. The pulsating torque, due to flux reduction, has been compensated by an ingenious feedforward scheme. During transient state, rated flux is established to get the best transient response. Through a comprehensive simulation study, the results confirmed the validity of the proposed method.

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Power Quality Disturbance Classification using Decision Fusion (결정결합 방법을 이용한 전력외란 신호의 식별)

  • 김기표;김병철;남상원
    • Proceedings of the IEEK Conference
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    • 2000.09a
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    • pp.915-918
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    • 2000
  • In this paper, we propose an efficient feature vector extraction and decision fusion methods for the automatic classification of power system disturbances. Here, FFT and WPT(wavelet packet transform) are und to extract an appropriate feature for classifying power quality disturbances with variable properties. In particular, the WPT can be utilized to develop an adaptable feature extraction algorithm using best basis selection. Furthermore. the extracted feature vectors are applied as input to the decision fusion system which combines the decisions of several classifiers having complementary performances, leading to improvement of the classification performance. Finally, the applicability of the proposed approach is demonstrated using some simulations results obtained by analyzing power quality disturbances data generated by using Matlab.

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A Spetrophotometric Cyanmethemoglobin Method for the Estimation of Serum Hemoglobin Levels (혈청(血情)해모구로빈 측정(測定)에 관(關)한 연구(硏究))

  • Tchai, B.S.;Cho, K.H.;Lee, C.K
    • Journal of Nutrition and Health
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    • v.7 no.4
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    • pp.30-32
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    • 1974
  • Hemoglobinemia is found in hemolytic anemia, paroxysmal nocturnal hemolobinuria and paroxysmal hemoglobinuria. Recently increasing use of extracorporeal circulation in cardiac surgery has stimulated the development of more precise methods for rapidly evaluating the formation and clearance of extracoporeal hemoglobin. A spectrophotometric method of analysis seemed to offer the best solution to the requirements. The method presented is on the basis of hemoglobin derivatives converted to cyanmethemoglobin, and the absorbance is measured in a spectrophotometer at 540 and 680 nm. The blank value ismeasured at 680 nm while the absorbance at 540 nm measures the hemoglobin derivatives. This method estimates all the hemoglobin derivatives such as oxyhemoglobin, carboxyhemoglobin, methemoglobin, sulfhemoglobin and hemialbumin. The method was tested in recovery experiments, which is given table 1. A good degree of correlation was obtained in a comparision with the method described by Crosby and Furth for non-hemolyzed serum. The spectrophotometric technique described offers many advantages in speed and simplicity over the chemical procedure.

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Development of the Machine Vision System for Inspection the Front-Chassis Module of an Automobile (자동차 프런트 샤시 모듈 측정을 위한 머신 비전 시스템 개발)

  • 이동목;이광일;양승한
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.13 no.3
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    • pp.84-90
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    • 2004
  • Today, automobile world market is highly competitive. In order to strengthen the competitiveness, quality of automobile is recognized as important and efforts are being made to improve the quality of manufactured components. The directional ability of automobile has influence on driver directly and hence it must be solved on the preferential basis. In the present research, an automated vision system has been developed to inspect the front chassis module. To interpret the inspection data obtained for front chassis module, new interpreting algorithm have been developed. Previously the control of tolerance of front chassis module was done manually. With the help of the new algorithm developed, the dimension is calculated automatically to check whether the front chassis module is within the tolerance limit or not.

Anomaly Detection in Smart Homes Using Bayesian Networks

  • Saqaeeyan, Sasan;javadi, Hamid Haj Seyyed;Amirkhani, Hossein
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.14 no.4
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    • pp.1796-1816
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    • 2020
  • The health and safety of elderly and disabled patients who cannot live alone is an important issue. Timely detection of sudden events is necessary to protect these people, and anomaly detection in smart homes is an efficient approach to extracting such information. In the real world, there is a causal relationship between an occupant's behaviour and the order in which appliances are used in the home. Bayesian networks are appropriate tools for assessing the probability of an effect due to the occurrence of its causes, and vice versa. This paper defines different subsets of random variables on the basis of sensory data from a smart home, and it presents an anomaly detection system based on various models of Bayesian networks and drawing upon these variables. We examine different models to obtain the best network, one that has higher assessment scores and a smaller size. Experimental evaluations of real datasets show the effectiveness of the proposed method.

Application of Envisat ASAR Image in Near Real Time Flood monitoring and Assessment in China

  • Huang, Shifeng
    • Proceedings of the Korea Water Resources Association Conference
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    • 2009.05a
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    • pp.2184-2189
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    • 2009
  • China is one of the countries in which flood occurs most frequently in the world and with the current economic growth; flood disaster causes more and more economic losses. Chinese government pays more attention to flood monitoring and assessment by space technology. Since1983, NOAA(AVHRR), Landsat-TM, LANDSAT-ETM+, JERS-1, SPOT, ERS-2, Radarsat-1, CBERS-1, Envisat have been used for flood monitoring and assessment. Due to the bad weather conditions during flood, microwave remote sensing is the major tools for flood monitoring. Envisat is one of the best satellite with powerful SAR. Its application for flood monitoring has been studied and its near real time(NRT) application can be realized on the basis of real-time delivery of image. During the 2005, 2006 and 2007 flood seasons, over the 31 NRT flood monitoring based on Envisat, had been carried out in Yangtze, Songua, Huaihe, pearl river basin. The result shows that Envisat SAR is very useful data source for flood disaster monitoring and assessment.

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