• Title/Summary/Keyword: Back-Propagation

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An Enhancement of Learning Speed of the Error - Backpropagation Algorithm (오류 역전도 알고리즘의 학습속도 향상기법)

  • Shim, Bum-Sik;Jung, Eui-Yong;Yoon, Chung-Hwa;Kang, Kyung-Sik
    • The Transactions of the Korea Information Processing Society
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    • v.4 no.7
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    • pp.1759-1769
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    • 1997
  • The Error BackPropagation (EBP) algorithm for multi-layered neural networks is widely used in various areas such as associative memory, speech recognition, pattern recognition and robotics, etc. Nevertheless, many researchers have continuously published papers about improvements over the original EBP algorithm. The main reason for this research activity is that EBP is exceeding slow when the number of neurons and the size of training set is large. In this study, we developed new learning speed acceleration methods using variable learning rate, variable momentum rate and variable slope for the sigmoid function. During the learning process, these parameters should be adjusted continuously according to the total error of network, and it has been shown that these methods significantly reduced learning time over the original EBP. In order to show the efficiency of the proposed methods, first we have used binary data which are made by random number generator and showed the vast improvements in terms of epoch. Also, we have applied our methods to the binary-valued Monk's data, 4, 5, 6, 7-bit parity checker and real-valued Iris data which are famous benchmark training sets for machine learning.

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The Font Recognition of Printed Hangul Documents (인쇄된 한글 문서의 폰트 인식)

  • Park, Moon-Ho;Shon, Young-Woo;Kim, Seok-Tae;Namkung, Jae-Chan
    • The Transactions of the Korea Information Processing Society
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    • v.4 no.8
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    • pp.2017-2024
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    • 1997
  • The main focus of this paper is the recognition of printed Hangul documents in terms of typeface, character size and character slope for IICS(Intelligent Image Communication System). The fixed-size blocks extracted from documents are analyzed in frequency domain for the typeface classification. The vertical pixel counts and projection profile of bounding box are used for the character size classification and the character slope classification, respectively. The MLP with variable hidden nodes and error back-propagation algorithm is used as typeface classifier, and Mahalanobis distance is used to classify the character size and slope. The experimental results demonstrated the usefulness of proposed system with the mean rate of 95.19% in typeface classification. 97.34% in character size classification, and 89.09% in character slope classification.

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Aerodynamic Approaches for the Predition of Spread the HPAI (High Pathogenic Avian Influenza) on Aerosol (고병원성 조류인플루엔자 (HPAI)의 에어로졸을 통한 공기 전파 예측을 위한 공기유동학적 확산 모델 연구)

  • Seo, Il-Hwan;Lee, In-Bok;Moon, Oun-Kyung;Hong, Se-Woon;Hwnag, Hyun-Seob;Bitog, J.P.;Kwon, Kyeong-Seok;Kim, Ki-Youn
    • Journal of The Korean Society of Agricultural Engineers
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    • v.53 no.1
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    • pp.29-36
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    • 2011
  • HPAI (High pathogenic avian influenza) which is a disease legally designated as an epidemic generally shows rapid spread of disease resulting in high mortality rate as well as severe economic damages. Because Korea is contiguous with China and southeast Asia where HPAI have occurred frequently, there is a high risk for HPAI outbreak. A prompt treatment against epidemics is most important for prevention of disease spread. The spread of HPAI should be considered by both direct and indirect contact as well as various spread factors including airborne spread. There are high risk of rapid propagation of HPAI flowing through the air because of collective farms mostly in Korea. Field experiments for the mechanism of disease spread have limitations such as unstable weather condition and difficulties in maintaining experimental conditions. In this study, therefore, computational fluid dynamics which has been actively used for mass transfer modeling were adapted. Korea has complex terrains and many livestock farms are located in the mountain regions. GIS numerical map was used to estimate spreads of virus attached aerosol by means of designing three dimensional complicated geometry including farm location, road network, related facilities. This can be used as back data in order to take preventive measures against HPAI occurrence and spread.

A Study on Distance Relay of Transmission UPFC Using Artificial Neural Network (신경회로망을 이용한 UPFC가 연계된 송전선로의 거리계전기에 관한 연구)

  • Lee, Jun-Kyong;Park, Jeong-Ho;Lee, Seung-Hyuk;Kim, Jin-O
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.18 no.6
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    • pp.37-44
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    • 2004
  • This paper represents a new approach for the protective relay of power transmission lines using a Artificial Neural Network(ANN). A different fault m transmission lines need to be detected classified and located accurately and cleared as fast as possible. However, The protection range of the distance relay is always designed on the basis of fixed settings, and unfortunately these approach do not have the ability to adapt dynamically to the system operating condition. ANN is suitable for the adaptive relaying and the detection of complex faults. The backpropagation algerian based multi-layer protection is utilized for the teaming process. It allows to make control to various protection functions. As expected, the simulation result demonstrate that this approach is useful and satisfactory.

Multiaspect-based Active Sonar Target Classification Using Deep Belief Network (DBN을 이용한 다중 방위 데이터 기반 능동소나 표적 식별)

  • Kim, Dong-wook;Bae, Keun-sung;Seok, Jong-won
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.22 no.3
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    • pp.418-424
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    • 2018
  • Detection and classification of underwater targets is an important issue for both military and non-military purposes. Recently, many performance improvements are being reported in the field of pattern recognition with the development of deep learning technology. Among the results, DBN showed good performance when used for pre-training of DNN. In this paper, DBN was used for the classification of underwater targets using active sonar, and the results are compared with that of the conventional BPNN. We synthesized active sonar target signals using 3-dimensional highlight model. Then, features were extracted based on FrFT. In the single aspect based experiment, the classification result using DBN was improved about 3.83% compared with the BPNN. In the case of multi-aspect based experiment, a performance of 95% or more is obtained when the number of observation sequence exceeds three.

Development of Estimation Model of Construction Activity Duration Using Neural Network Theory (건설공사 공정별 작업기간 산정을 위한 신경망 기반 모형 구축)

  • Cho, Bit-Na;Kim, Hyeon-Seung;Kang, Leen-Seok
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.5
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    • pp.3477-3483
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    • 2015
  • A reasonable process for the activity duration estimation is required for the successful construction management because it directly affects the entire construction duration and budget. However, the activity duration is being generally estimated by the experience of the construction manager. This study suggests an estimation model of construction activity duration using neural network theory. This model estimates the activity duration by considering both the quantitative and qualitative elements, and the model is verified by a case study. Because the suggested model estimates the activity duration by a reasonable schedule plan, it is expected to reduce the error between planning duration and actual duration in a construction project.

A Dynamic Three Dimensional Neuro System with Multi-Discriminator (다중 판별자를 가지는 동적 삼차원 뉴로 시스템)

  • Kim, Seong-Jin;Lee, Dong-Hyung;Lee, Soo-Dong
    • Journal of KIISE:Software and Applications
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    • v.34 no.7
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    • pp.585-594
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    • 2007
  • The back propagation algorithm took a long time to learn the input patterns and was difficult to train the additional or repeated learning patterns. So Aleksander proposed the binary neural network which could overcome the disadvantages of BP Network. But it had the limitation of repeated learning and was impossible to extract a generalized pattern. In this paper, we proposed a dynamic 3 dimensional Neuro System which was consisted of a learning network which was based on weightless neural network and a feedback module which could accumulate the characteristic. The proposed system was enable to train additional and repeated patterns. Also it could be produced a generalized pattern by putting a proper threshold into each learning-net's discriminator which was resulted from learning procedures. And then we reused the generalized pattern to elevate the recognition rate. In the last processing step to decide right category, we used maximum response detector. We experimented using the MNIST database of NIST and got 99.3% of right recognition rate for training data.

Servo Control of Hydraulic Motor using Artificial Intelligence (인공지능을 이용한 유압모터의 서보제어)

  • 신위재;허태욱
    • Journal of the Institute of Convergence Signal Processing
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    • v.4 no.3
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    • pp.49-54
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    • 2003
  • In this paper, we propose a controller with the self-organizing neural network compensator for compensating PID controller's response. PID controller has simple design method but needs a lot of trials and errors to determine coefficients. A neural network control method does not have optimal structure as the parameters are pre-specified by designers. In this paper, to solve this problem, we use a self-organizing neural network which has Back Propagation Network algorithm using a Gaussian Potential Function as an activation function of hidden layer nodes for compensating PID controller's output. Self-Organizing Neural Network's learning is proceeded by Gaussian Function's Mean, Variance and number which are automatically adjusted. As the results of simulation through the second order plant, we confirmed that the proposed controller get a good response compare with a PID controller. And we implemented the of controller performance hydraulic servo motor system using the DSP processor. Then we observed an experimental results.

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Implementation of Neural Filter Optimal Algorithms for Image Restoration (영상복원용 신경회로망 필터의 최적화 알고리즘 구현)

  • Lee, Bae-Ho;Mun, Byeong-Jin
    • The Transactions of the Korea Information Processing Society
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    • v.6 no.7
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    • pp.1980-1987
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    • 1999
  • Restored image is always lower quality than original one due to distortion and noise. The purpose of image restoration is to improve the image quality by fixing the noise or distortion information. One category of spatial filters for image restoration is linear filter. This filter algorithm is easily implemented and can be suppressed the Gaussian noise effectively, but not so good performance for spot or impulse noise. In this paper, we propose the nonlinear spatial filter algorithm for image restoration called the optimal adaptive multistage filter(OAMF). The OAMF is used to reduce the filtering time, increases the noise suppression ratio and preserves the edge information. The OAMF optimizes the adaptive multistage filter(AMF) by using weight learning algorithm of back-propagation learning algorithm. Simulation results of this filter algorithm are presented and discussed.

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Development and Application of Total Maximum Daily Loads Simulation System Using Nonpoint Source Pollution Model (비점원오염모델을 이용한 오염총량모의시스템의 개발 및 적용)

  • Kang, Moon-Seong;Park, Seung-Woo
    • Journal of Korea Water Resources Association
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    • v.36 no.1
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    • pp.117-128
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    • 2003
  • The objectives of this study are to develop the total maximum daily loads simulation system, TOLOS that is capable of estimating annual nonpoint source pollution from small watersheds, to monitor the hydrology and water quality of the Balkan HP#6 watershed, and to validate TOLOS with the field data. TOLOS consists of three subsystems: the input data processor based on a geographic information system, the models, and the post processor. Land use pattern at the tested watershed was classified from the Landsat TM data using the artificial neutral network model that adopts an error back propagation algorithm. Paddy field components were added to SWAT model to simulate water balance at irrigated paddy blocks. SWAT model parameters were obtained from the GIS data base, and additional parameters calibrated with field data. TOLOS was then tested with ungauged conditions. The simulated runoff was reasonably good as compared with the observed data. And simulated water quality parameters appear to be reasonably comparable to the field data.