• 제목/요약/키워드: Artificial Neural Network

검색결과 3,072건 처리시간 0.038초

인공 신경망을 이용한 채소 단수 예측 모형 개발: 고추를 중심으로 (Development of Yield Forecast Models for Vegetables Using Artificial Neural Networks: the Case of Chilli Pepper)

  • 이춘수;양성범
    • 한국유기농업학회지
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    • 제25권3호
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    • pp.555-567
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    • 2017
  • This study suggests the yield forecast model for chilli pepper using artificial neural network. For this, we select the most suitable network models for chilli pepper's yield and compare the predictive power with adaptive expectation model and panel model. The results show that the predictive power of artificial neural network with 5 weather input variables (temperature, precipitation, temperature range, humidity, sunshine amount) is higher than the alternative models. Implications for forecasting of yields are suggested at the end of this study.

인공 신경망을 이용한 절삭력 간접 측정 (Indirect Cutting Force Estimation Using Artificial Neural Network)

  • 최지현;김종원
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1995년도 추계학술대회 논문집
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    • pp.1054-1058
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    • 1995
  • There have been many research works for the indirect cutting force measurement in machining process, which deal with the case of one-axis cutting process. In multi-axis cutting process, the main difficulties to estimate the cutting forces occur when the feed direction is reversed. This paper presents the indirect cutting force measurement method in contour NC milling processes by using current signals of servo motors. An artificial neural network (ANN) system are suggested. An artificial neural network(ANN) system is also implemented with a training set of experimental cutting data to measure cutting force indirectly. The input variables of the ANN system are the motor currents and the feedrates of x and y-axis servo motors, and output variable is the cutting force of each axis. A series of experimental works on the circular interpolated contour milling process with the path of a complete circle has been performed. It is concluded that by comparing the ANN system with a dynamometer measuring cutting force directil, the ANN system has a good performance.

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Application of wavelet multiresolution analysis and artificial intelligence for generation of artificial earthquake accelerograms

  • Amiri, G. Ghodrati;Bagheri, A.
    • Structural Engineering and Mechanics
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    • 제28권2호
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    • pp.153-166
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    • 2008
  • This paper suggests the use of wavelet multiresolution analysis (WMRA) and neural network for generation of artificial earthquake accelerograms from target spectrum. This procedure uses the learning capabilities of radial basis function (RBF) neural network to expand the knowledge of the inverse mapping from response spectrum to earthquake accelerogram. In the first step, WMRA is used to decompose earthquake accelerograms to several levels that each level covers a special range of frequencies, and then for every level a RBF neural network is trained to learn to relate the response spectrum to wavelet coefficients. Finally the generated accelerogram using inverse discrete wavelet transform is obtained. An example is presented to demonstrate the effectiveness of the method.

인공신경망과 유전 알고리즘을 이용한 팩맨 게임 강화학습 (Pacman Game Reinforcement Learning Using Artificial Neural-network and Genetic Algorithm)

  • 박진수;이호정;황두연;조수선
    • 대한임베디드공학회논문지
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    • 제15권5호
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    • pp.261-268
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    • 2020
  • Genetic algorithms find the optimal solution by mimicking the evolution of natural organisms. In this study, the genetic algorithm was used to enable Pac-Man's reinforcement learning, and a simulator to observe the evolutionary process was implemented. The purpose of this paper is to reinforce the learning of the Pacman AI of the simulator, and utilize genetic algorithm and artificial neural network as the method. In particular, by building a low-power artificial neural network and applying it to a genetic algorithm, it was intended to increase the possibility of implementation in a low-power embedded system.

신경회로망 모델을 이용한 선삭 공정의 실시간 이상진단 시스템의 개발 (Development of In process Condition Monitoring System on Turning Process using Artificial Neural Network.)

    • 한국생산제조학회지
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    • 제7권3호
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    • pp.14-21
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    • 1998
  • The in-process detection of the state of cutting tool is one of the most important technical problem in Intelligent Machining System. This paper presents a method of detecting the state of cutting tool in turning process, by using Artificial Neural Network. In order to sense the state of cutting tool. the sensor fusion of an acoustic emission sensor and a force sensor is applied in this paper. It is shown that AErms and three directional dynamic mean cutting forces are sensitive to the tool wear. Therefore the six pattern features that is, the four sensory signal features and two cutting conditions are selected for the monitoring system with Artificial Neural Network. The proposed monitoring system shows a good recogniton rate for the different cutting conditions.

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인공 신경망 모델을 활용한 조미니 곡선 예측 (Prediction of Jominy Curve using Artificial Neural Network)

  • 이운재;이석재
    • 열처리공학회지
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    • 제31권1호
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    • pp.1-5
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    • 2018
  • This work demonstrated the application of an artificial neural network model for predicting the Jominy hardness curve by considering 13 alloying elements in low alloy steels. End-quench Jominy tests were carried out according to ASTM A255 standard method for 1197 samples. The hardness values of Jominy sample were measured at different points from the quenched end. The developed artificial neural network model predicted the Jominy curve with high accuracy ($R^2=0.9969$ for training and $R^2=0.9956$ for verification). In addition, the model was used to investigate the average sensitivity of input variables to hardness change.

인공신경망기법을 이용한 깊은 굴착에 따른 지표변위 예측 (Prediction of Deep Excavation-induced Ground Surface Movements Using Artificial Neural Network)

  • 유충식;최병석
    • 한국지반공학회논문집
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    • 제20권3호
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    • pp.53-65
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    • 2004
  • 본 연구에서는, 굴착 공사로 인한 주변 건물 손상 평가의 일환으로 지표 변위유형의 효과적인 예측 방안을 제시하였다. 먼저 검증된 유한요소 모델을 국내에서 행해지는 다양한 경우의 굴착특성으로 해석한 결과를 통해 인접 지반의 거동에 대한 매개 변수 연구를 수행하였고, 인공신경망 엔진의 학습을 위한 데이터베이스를 구축하였다. 최적의 구조로 학습된 신경망 엔진은 간단한 굴착 특성으로 다양하게 나타나는 지표 변위 유형 예측에 효율적임을 검증하였다.

HAI 제어기에 의한 IPMSM 드라이브의 속도 추정 및 제어 (Speed Estimation and Control of IPMSM Drive with HAI Controller)

  • 이홍균;이정철;정동화
    • 대한전기학회논문지:시스템및제어부문D
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    • 제54권4호
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    • pp.220-227
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    • 2005
  • This paper presents hybrid artificial intelligent(HAI) controller based on the vector controlled IPMSM drive system. And it is based on artificial technologies that adaptive neural network fuzzy(A-NNF) is to speed control and artificial neural network(ANN) is to speed estimation. The salient feature of this technique is the HAI controller The hybrid action tolerates any inaccuracies in the fuzzy logic assignment rules or in the neural network stationary weights. Speed estimators using feedforward multilayer and artificial neural network(ANN) are compared. The back-propagation algorithm is easy to derived the estimated speed tracks precisely the actual motor speed. This paper presents the theoretical analysis as well as the simulation results to verify the effectiveness of the new hybrid intelligent control.

웨이블릿 패킷변환과 신경망을 결합한 하천수위 예측모델 (River Stage Forecasting Model Combining Wavelet Packet Transform and Artificial Neural Network)

  • 서영민
    • 한국환경과학회지
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    • 제24권8호
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    • pp.1023-1036
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    • 2015
  • A reliable streamflow forecasting is essential for flood disaster prevention, reservoir operation, water supply and water resources management. This study proposes a hybrid model for river stage forecasting and investigates its accuracy. The proposed model is the wavelet packet-based artificial neural network(WPANN). Wavelet packet transform(WPT) module in WPANN model is employed to decompose an input time series into approximation and detail components. The decomposed time series are then used as inputs of artificial neural network(ANN) module in WPANN model. Based on model performance indexes, WPANN models are found to produce better efficiency than ANN model. WPANN-sym10 model yields the best performance among all other models. It is found that WPT improves the accuracy of ANN model. The results obtained from this study indicate that the conjunction of WPT and ANN can improve the efficiency of ANN model and can be a potential tool for forecasting river stage more accurately.

Optimization of Culture Conditions and Bench-Scale Production of $_L$-Asparaginase by Submerged Fermentation of Aspergillus terreus MTCC 1782

  • Gurunathan, Baskar;Sahadevan, Renganathan
    • Journal of Microbiology and Biotechnology
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    • 제22권7호
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    • pp.923-929
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    • 2012
  • Optimization of culture conditions for L-asparaginase production by submerged fermentation of Aspergillus terreus MTCC 1782 was studied using a 3-level central composite design of response surface methodology and artificial neural network linked genetic algorithm. The artificial neural network linked genetic algorithm was found to be more efficient than response surface methodology. The experimental $_L$-asparaginase activity of 43.29 IU/ml was obtained at the optimum culture conditions of temperature $35^{\circ}C$, initial pH 6.3, inoculum size 1% (v/v), agitation rate 140 rpm, and incubation time 58.5 h of the artificial neural network linked genetic algorithm, which was close to the predicted activity of 44.38 IU/ml. Characteristics of $_L$-asparaginase production by A. terreus MTCC 1782 were studied in a 3 L bench-scale bioreactor.