• Title/Summary/Keyword: neural network techniques

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Object Tracking Using Weighted Average Maximum Likelihood Neural Network (최대우도 가중평균 신경망을 이용한 객체 위치 추적)

  • Sun-Bae Park;Do-Sik Yoo
    • Journal of Advanced Navigation Technology
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    • v.27 no.1
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    • pp.43-49
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    • 2023
  • Object tracking is being studied with various techniques such as Kalman filter and Luenberger tracker. Even in situations, such as the one in which the system model is not well specified, to which existing signal processing techniques are not successfully applicable, it is possible to design artificial neural networks to track objects. In this paper, we propose an artificial neural network, which we call 'maximum-likelihood weighted-average neural network', to continuously track unpredictably moving objects. This neural network does not directly estimate the locations of an object but obtains location estimates by making weighted average combining various results of maximum likelihood tracking with different data lengths. We compare the performance of the proposed system with those of Kalman filter and maximum likelihood object trackers and show that the proposed scheme exhibits excellent performance well adapting the change of object moving characteristics.

Modern Methods of Text Analysis as an Effective Way to Combat Plagiarism

  • Myronenko, Serhii;Myronenko, Yelyzaveta
    • International Journal of Computer Science & Network Security
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    • v.22 no.8
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    • pp.242-248
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    • 2022
  • The article presents the analysis of modern methods of automatic comparison of original and unoriginal text to detect textual plagiarism. The study covers two types of plagiarism - literal, when plagiarists directly make exact copying of the text without changing anything, and intelligent, using more sophisticated techniques, which are harder to detect due to the text manipulation, like words and signs replacement. Standard techniques related to extrinsic detection are string-based, vector space and semantic-based. The first, most common and most successful target models for detecting literal plagiarism - N-gram and Vector Space are analyzed, and their advantages and disadvantages are evaluated. The most effective target models that allow detecting intelligent plagiarism, particularly identifying paraphrases by measuring the semantic similarity of short components of the text, are investigated. Models using neural network architecture and based on natural language sentence matching approaches such as Densely Interactive Inference Network (DIIN), Bilateral Multi-Perspective Matching (BiMPM) and Bidirectional Encoder Representations from Transformers (BERT) and its family of models are considered. The progress in improving plagiarism detection systems, techniques and related models is summarized. Relevant and urgent problems that remain unresolved in detecting intelligent plagiarism - effective recognition of unoriginal ideas and qualitatively paraphrased text - are outlined.

STEPANOV ALMOST PERIODIC SOLUTIONS OF CLIFFORD-VALUED NEURAL NETWORKS

  • Lee, Hyun Mork
    • Journal of the Chungcheong Mathematical Society
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    • v.35 no.1
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    • pp.39-52
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    • 2022
  • We introduce Clifford-valued neural networks with leakage delays. Furthermore, we study the uniqueness and existence of Clifford-valued Hopfield artificial neural networks having the Stepanov weighted pseudo almost periodic forcing terms on leakage delay terms. However the noncommutativity of the Clifford numbers' multiplication made our investigation diffcult, so our results are obtained by decomposing Clifford-valued neural networks into real-valued neural networks. Our analysis is based on the differential inequality techniques and the Banach contraction mapping principle.

Design of Neural-Network Based Autopilot Control System(II) (신경망을 이용한 선박용 자동조타장치의 제어시스템 설계 (II))

  • Kwak, Moon Kyu;Suh, Sang-Hyun
    • Journal of the Society of Naval Architects of Korea
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    • v.34 no.3
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    • pp.19-26
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    • 1997
  • This paper is concerned with the design of neural-network based autopilot control system. The back-propagation neural network introduced in the previous paper by authors is applied to the autopilot control system. As a result, two neural-network controllers are developed, which are the model reference adaptive neural controller and the instantaneous optimal neural controller. The model reference adaptive neural controller is the control technique that the heading angle and angular velocity are controlled by the rudder angle to follow the output of the reference model. The instantaneous optimal neural controller optimizes the transition from one state to the next state. These control techniques are applied to a simple ship maneuvering model and their effectiveness is proved by numerical examples.

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Precision indices of neural networks for medicines: structure-activity correlation relationships

  • Zhu, Hanxi;Aoyama, Tomoo;Yoshihara, Ikuo;Lee, Seung-Woo;Kim, Wook-Hyun
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.481-481
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    • 2000
  • We investigated the structure-activity relationships on use of multi-layer neural networks. The relationships are techniques required in developments of medicines. Since many kinds of observations might be adopted on the techniques, we discussed some points between the observations and the properties of multi-layer neural networks. In the structure-activity relationships, an important property is not that standard deviations are nearly equal to zero for observed physiological activity, but prediction ability for unknown medicines. Since we adopted non-linear approximation, the function to represent the activity can be defined by observations; therefore, we believe that the standard deviations have not significance. The function was examined by "leave-one-out" method, which was originally introduced for the multi-regression analysis. In the linear approximation, the examination is significance, however, we believe that the method is inappropriate in case of nonlinear fitting as neural networks; therefore, we derived a new index fer the relationships from the differential of information propagation in the neural network. By using the index, we discussed physiological activity of an anti-cancer medicine, Mitomycine derivatives. The neuro-computing suggests that there is no direction to extend the anti-cancer activity of Mitomycine, which is close to the trend of anticancer developing.

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Detection of Main Spindle Bearing Defects in Machine Tool by Acoustic Emission Signal via Neural Network Methodology (AE 신호 및 신경회로망을 이용한 공작기계 주축용 베어링 결함검출)

  • 정의식
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.6 no.4
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    • pp.46-53
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    • 1997
  • This paper presents a method of detection localized defects on tapered roller bearing in main spindle of machine tool system. The feature vectors, i.e. statistical parameters, in time-domain analysis technique have been calculated to extract useful features from acoustic emission signals. These feature vectors are used as the input feature of an neural network to classify and detect bearing defects. As a results, the detection of bearing defect conditions could be sucessfully performed by using an neural network with statistical parameters of acoustic emission signals.

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Detection of Main Spindle Bearing Conditions in Machine Tool via Neural Network Methodolog (신경회로망을 이용한 공작기계 주축용 베어링의 고장검지)

  • Oh, S.Y.;Chung, E.S.;Lim, Y.H.
    • Journal of the Korean Society for Precision Engineering
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    • v.12 no.5
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    • pp.33-39
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    • 1995
  • This paper presents a method of detecting localized defects on tapered roller bearing in main spindle of machine tool system. The statistical parameters in time-domain processing technique have been calculated to extract useful features from bearing vibration signals. These features are used by the input feature of an artificial neural network to detect and diagnose bearing defects. As a results, the detection of bearing defect conditions could be successfully performed by using an artificial neural network with statistical parameters of acceleration signals.

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A Position Sensorless Control System of SRM over Wide Speed Range

  • Baik, Won-Sik
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.22 no.3
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    • pp.66-73
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    • 2008
  • This paper presents a position sensorless control system of SRM over wide speed range. Due to the doubly salient structure of the SRM, the phase inductance varies along with the rotor position. Most of the sensorless control techniques are based on the fact that the magnetic status of the SRM is a function of the angular rotor position. The rotor position estimation of the SRM is somewhat difficult because of its highly nonlinear magnetizing characteristics. In order to estimate more accurate rotor position over wide speed range, Neural Network is used for this highly nonlinear function approximation. Magnetizing data patterns of the prototype 1-hp SRM are obtained from locked rotor test, and used for the Neural Network training data set. Through measurement of the flux-linkage and phase currents, rotor position is able to estimate from current-flux-rotor position lookup table which is constructed from trained Neural Network. Experimental results for a 1-hp SRM over 16:1 speed range are presented for the verification of the proposed sensorless control algorithm.

Structural Vibration Control Technique using Modified Probabilistic Neural Network

  • Chang, Seong-Kyu;Kim, Doo-Kie
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.23 no.6
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    • pp.667-673
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    • 2010
  • Recently, structures are becoming longer and higher because of the developments of new materials and construction techniques. However, such modern structures are more susceptible to excessive structural vibrations which cause deterioration in serviceability and structural safety. A modified probabilistic neural network(MPNN) approach is proposed to reduce the structural vibration. In this study, the global probability density function(PDF) of MPNN is reflected by summing the heterogeneous local PDFs automatically determined in the individual standard deviation of each variable. The proposed algorithm is applied for the vibration control of a three-story shear building model under Northridge earthquake. When the control results of the MPNN are compared with those of conventional PNN to verify the control performance, the MPNN controller proves to be more effective than PNN methods in decreasing the structural responses.

A SMP Forecasting Method Based on Artificial Neural Network Using Time and Day Information (시간축 및 요일축 정보의 조합을 이용한 신경회로망 기반의 평일 계통한계가격 예측)

  • Lee, Jeong-Kyu;Kim, Min-Soo;Park, Jong-Bae;Shin, Joong-Rin
    • Proceedings of the KIEE Conference
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    • 2003.11a
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    • pp.438-440
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    • 2003
  • This paper resents an application of an Artificial Neural Network(ANN) technique to forecast the short-term system marginal price(SMP). The forecasting of SMP is a very important factor in an electricity market for the optimal biddings of market participants as well as for the market stabilization of regulatory bodies. The proposed neural network scheme is composed of three layers. In this process, input data are set up to reflect market conditions. And the $\lambda$ that is the coefficient of activation function is modified in order to give a proper signal to each neuron and improve the adaptability for a neural network. The reposed techniques are trained validated and tested with the historical real-world data from korea Power Exchange(KPX).

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