• Title/Summary/Keyword: forward / backward propagation

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Input-Output Analysis on the Medical Service Industry between Korea and Japan (의료서비스산업의 산업연관분석)

  • 이견직;정영호
    • Health Policy and Management
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    • v.10 no.1
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    • pp.126-147
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    • 2000
  • This paper empirically explores the nature of the medical service industry and its various propagation effects on the economy in the input-output model, as revealed by a comparative analysis between Korea and Japan. The main findings of the paper are as follows; First, the growth of medical industry induces above-average effect on employment. Second, the industry is of the characteristics of weak both backward and forward linkage effects implying a 'final demand dependency industry'. When compared with public service sectors, however, the medical services industry shows stronger backward linkage effect than those sectors. Furthermore, it has strong repercussion effects on the goods industries. Third, in order to produce per unit of services, the medical services industry of Korea uses relatively more drugs and medical devices than that of Japan. In general, it has been shown that production structure of medical service industry in Korea is 'hardware-oriented' one; on the other hand, 'software-oriented' in Japan which means that, as intermediate inputs, outsourcing and informatization has been used than those of Korea. From the findings of the paper it could be emphasized that the medical organizations in Korea should put more efforts on shifting the current hardware-oriented production structure to strengthen core competence by enhancing productivity and by outsourcing to improve efficiency of production process. However, the medical organizations in Korea would not have enough incentives for high value-added production structure because they enjoy high operating surplus. Therefore, it would be necessary that government policy should be taken into account of these environments.

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Object Extraction technique Using Belief Propagation Stereo Algorithm of Bidirectional Search based on Brightness (밝기기반 양방향 탐색기법의 신뢰전파 스테레오 알고리즘을 이용한 물체 추출 기법)

  • Choi, Young-Seok;Choi, Kyung-Seok;Kang, Hyun-Soo
    • Proceedings of the IEEK Conference
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    • 2007.07a
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    • pp.313-314
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    • 2007
  • In this paper, we suggest robust object extraction algorithm taking advantage of efficient Belief Propagation method. It does not get a disparity information because of uniform region and occlusion region etc. on initial depth map that use forward direction disparity information although is object area. Therefore, We run parallel backward disparity information and brightness information for certain object extraction.

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Determination of Phase Velocity Dispersion Curve and Group Velocity of lamb Waves Using Backward Radiation (후방복사를 이용한 램파의 위상속도 분산과 군속도의 측정)

  • 송성진;권성덕;정용무;김영환
    • The Journal of the Acoustical Society of Korea
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    • v.22 no.1
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    • pp.61-68
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    • 2003
  • The guided wave has been widely employed to characterize thin plates and layered media. The dispersion curves of phase and group velocities are essential for the quantitative application of guided waves. In the present work, a fully automated system for the measurement of backward radiation of LLW has been developed. The specimen moves in two dimensional plane as well as in angular rotation. The signals of backward radiation of LLW were measured from an elastic plate in which specific modes of Lamb wave were strongly generated. Phase velocity of the corresponding modes was determined from the incident angle. The generated Lamb waves propagated forward and backward with the leakage of energy into water. Backward radiated LLW was detected by the same transducer and its frequency components were analyzed to extract the related information to the dispersion curves. The dispersion curves of phase velocity were measured by varying the incident angle. Moving the specimen in the linear direction of LLW propagation, group velocity was determined by measuring the transit time shift in the ultrasonic waveform.

Investigating the Spatial Focusing of Time Reversal Lamb Waves Using a Virtual Sensor Model on a Rectangular Plate (직사각형 판에서 가상탐지자 모델을 이용한 시간반전램파의 공간모임 규명)

  • Park, Hyun-Woo
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.24 no.5
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    • pp.553-567
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    • 2011
  • During the last three years, the possibility of the time reversal Lamb waves has been paid attention to for structural health monitoring of a plate. This study proposes a numerical scheme which can simulate the spatial focusing of time reversal Lamb waves on a rectangular plate. In this scheme, a time reversal process is formulated in the frequency domain using active virtual sensors being equivalent to the mirror effects of an actual sensor due to wave reflection on the plate boundary. Forward and backward Lamb wave propagations are represented by scalar functions for simulating the spatial focusing of time reversal Lamb waves. The validity of the proposed scheme is demonstrated through the comparison to the results of finite element analysis in which the spatial focusing of time reversal Lamb waves is realized by wafer-type piezoelectric(PZT) transducers collocated on a rectangular plate.

The Propagation Effects on the Regional Economy Induced by U-City Construction in Wha-sung and Dong-tan City (U-City 구축에 따른 지역경제 파급효과 - 화성.동탄지역을 중심으로 -)

  • Kim, Pang-Ryong;Cho, Byung-Sun;Jeong, Woo-Soo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.12B
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    • pp.1087-1098
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    • 2006
  • This study is unlike common Input-Output Analysis in the point that both RAS and methods are applied to the dynamic Input-Output Model simultaneously. We have analyzed the propagation effects on the regional economy from the investment generated by u-City construction in Wha-sung and Dong-tan City. The main results of the study are as follows. The total induced effect on production according to u-City construction in Wha-sung and Dong-tan City is estimated about 2.9 times. On the other hand, u-City industry is appreciated as a industry which a forward linkage effect is very high while a backward linkage effect is not that high.

A Study on Reasoning and Learning of Fuzzy Rules Using Neural Networks (신경회로망을 이용한 퍼지룰의 추론과 학습에 관한 연구)

  • 이계호;임영철;김이곤;조경영
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.18 no.2
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    • pp.231-238
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    • 1993
  • A rules of fuzzy control is to represent an expert‘s and engineer‘s ambiguous control knowledge of system with some lingustic rules. This rule is very difficult to represent perfectly because expert‘s knowledge is not precise and the rule is not perfect. We propose the fuzzy reasoning and learning to upgrade precision of imperfect rules successively after system running. In the proposed method, the precision of the backward part of a fuzzy rule is improved by back propagation learning method. Also, the method reasons the compatibility degree of the forward part of fuzzy rule by associative memory method. This method this is successfully applied to design auto-parking fuzzy controller in which expert‘s technology and knowledge are required in the limited area.

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Propagation Characteristic of Ultrasonic on Slit Defect in Butt Joint (맞대기 용접부내의 인공 결함에서 초음파의 전파특성)

  • 남영현
    • Journal of Welding and Joining
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    • v.14 no.6
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    • pp.37-47
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    • 1996
  • An ultrasonic testing uses the directivity of the ultrasonic wave which propagates in one direction. The directivity is expressed as the relationship between the propagate direction and its sound pressure. The directivity of ultrasonic wave is related to determination of testing sensitivity, scanning pitch and defect location. This paper investigated the directivity of ultrasonic wave, which scattered from slit defect located in heat-affected zone (HAZ) in butt joint using visualization method. The directivity of shear waves scattered from slit defect were different according to probe direction (far defect, near defect) and probe position (forward movement, maximum echo position, backward movement). The difference of directivity of reflection wave was existed between 2 MHz and 4 MHz angle probes. In the case of 2 MHz angle probe, the directivity of reflection wave was appeared sharp form because of the relation wave length and defect size.

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Development of Visual Odometry Estimation for an Underwater Robot Navigation System

  • Wongsuwan, Kandith;Sukvichai, Kanjanapan
    • IEIE Transactions on Smart Processing and Computing
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    • v.4 no.4
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    • pp.216-223
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    • 2015
  • The autonomous underwater vehicle (AUV) is being widely researched in order to achieve superior performance when working in hazardous environments. This research focuses on using image processing techniques to estimate the AUV's egomotion and the changes in orientation, based on image frames from different time frames captured from a single high-definition web camera attached to the bottom of the AUV. A visual odometry application is integrated with other sensors. An internal measurement unit (IMU) sensor is used to determine a correct set of answers corresponding to a homography motion equation. A pressure sensor is used to resolve image scale ambiguity. Uncertainty estimation is computed to correct drift that occurs in the system by using a Jacobian method, singular value decomposition, and backward and forward error propagation.

Systolic Array Simulator Construction for the Back-propagation ANN (역전파 ANN의 시스톨릭 어레이를 위한 시뮬레이터 개발)

  • 박기현;전상윤
    • Journal of Korea Society of Industrial Information Systems
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    • v.5 no.3
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    • pp.117-124
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    • 2000
  • A systolic array is a parallel processing system which consists of processing elements of basic computation capabilities, connected with regular and local communication lines. It has been known that a systolic array is on of effective systems to solve complicated communication problems occurred between densely connected neurons on ANN(Artificial Neural Network). In this paper, a systolic array simulator for the back-propagation ANN, which automatically constructs the proper systolic array for a given number of neurons of the ANN, is designed and constructed. With animation techniques of the simulators, it is easy for users to be able to examine the execution of the back-propagation algorithm on the designed systolic array step by step. Moreover the simulator can perform forward and backward operations of the back-propagation algorithm either in sequence or in parallel on the designed systolic array. Parallel execution can be performed by feeding continuous input patterns and by executing bidirectional propagations on all of processing elements of a systolic array at the same time.

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Search for optimal time delays in universal learning network

  • Han, Min;Hirasawa, Kotaro;Ohbayashi, Masanao;Fujita, Hirofumi
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10a
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    • pp.95-98
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    • 1996
  • Universal Learning Network(U.L.N.), which can model and control the large scale complicated systems naturally, consists of nonlinearly operated nodes and multi-branches that may have arbitrary time delays including zero or minus ones. Therefore, U.L.N. can be applied to many kinds of systems which are difficult to be expressed by ordinary first order difference equations with one sampling time delay. It has been already reported that learning algorithm of parameter variables in U.L.N. by forward and backward propagation is useful for modeling, managing and controlling of the large scale complicated systems such as industrial plants, economic, social and life phenomena. But, in the previous learning algorithm of U.L.N., time delays between the nodes were fixed, in other words, criterion function of U.L.N. was improved by adjusting only parameter variables. In this paper, a new learning algorithm is proposed, where not only parameter variables but also time delays between the nodes can be adjusted. Because time delays are integral numbers, adjustment of time delays can be carried out by a kind of random search procedure which executes intensified and diversified search in a single framework.

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