• 제목/요약/키워드: best first

검색결과 3,350건 처리시간 0.026초

근전도의 정량적 분석시 사용되는 수리적 파라미터의 민감도 비교 (The Comparison of Sensitivity of Numerical Parameters for Quantification of Electromyographic (EMG) Signal)

  • 김정룡;정명철
    • 대한산업공학회지
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    • 제25권3호
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    • pp.330-335
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    • 1999
  • The goal of the study is to determine the most sensitive parameter to represent the degree of muscle force and fatigue. Various numerical parameters such as the first coefficient of Autoregressive (AR) Model, Root Mean Square (RMS), Zero Crossing Rate (ZCR), Mean Power Frequency (MPF), Median Frequency (MF) were tested in this study. Ten healthy male subjects participated in the experiment. They were asked to extend their trunk by using the right and left erector spinae muscles during a sustained isometric contraction for twenty seconds. The force levels were 15%, 30%, 45%, 60%, and 75% of Maximal Voluntary Contraction (MVC), and the order of trials was randomized. The results showed that RMS was the best parameter to measure the force level of the muscle, and that the first coefficient of AR model was relatively sensitive parameter for the fatigue measurement at less than 60% MVC condition. At the 75% MVC, however, both MPF and the first coefficient of AR Model showed the best performance in quantification of muscle fatigue. Therefore, the sensitivity of measurement can be improved by properly selecting the parameter based upon the level of force during a sustained isometric condition.

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자동화된 변전소의 이벤트 발생시 준최적 탐색법에 기반한 모선 재구성 전략의 개발 (Bus Reconfiguration Strategy Based on Local Minimum Tree Search for the Event Processing of Automated Distribution Substation)

  • 고윤석
    • 대한전기학회논문지:전력기술부문A
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    • 제53권10호
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    • pp.565-572
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    • 2004
  • This paper proposes an expert system which can enhance the accuracy of real-time bus reconfiguration strategy by adopting local minimum tree search method and minimize the spreading effect of the fault by considering totally the operating condition when a main transformer fault occurs in the automated substation. The local minimum tree search method to expand the best-first search method. This method has an advantage which can improve the performance of solution within the limits of the real-time condition. The inference strategy proposed expert system consists of two stages. The first stage determines the switching candidate set by searching possible switching candidates starting from the main transformer or busbar related to the event. And, second stage determines the rational real-time bus reconfiguration strategy based on heuristic rules for the obtained switching candidate set. Also, this paper studies the generalized distribution substation modelling using graph theory and a substation database is designed based on the study result. The inference engine of the expert system and the substation database is implemented in MFC function of Visual C++. Finally, the performance and effectiveness of the proposed expert system is verified by comparing the best-first search solution and local minimum tree search solution based on diversity event simulations for typical distribution substation.

PBL 우수 사례자로 선정된 교수들의 수업운영 전략 탐색 (A Research on PBL Implementation Strategy of Faculty Members Selected as a PBL Best Practicer)

  • 금혜진
    • 융합정보논문지
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    • 제9권10호
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    • pp.163-169
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    • 2019
  • 본 연구의 목적은 대학교에서 PBL 수업을 우수하게 운영하는 교수들의 수업운영 전략을 탐색하는 것이다. 이를 위해 충남에 위치한 B대학에서 2017년 1학기, 2학기, 2018년 1학기동안 PBL 우수 사례자로 선정된 교수 6명이 작성한 수업결과 보고서와 사례발표회 발표 자료를 활용하여 수업운영 전략 관련 내용을 귀납적 분석방법을 통해 분석하였다. 연구결과 PBL 우수 사례자로 선정된 교수들은 수업운영 시 교실문화, 학습촉진, 평가의 3개 영역과 관련하여 13개의 전략을 사용하고 있음이 규명되었다. 향후 필요한 연구와 지원을 제안하면 다음과 같다. 첫째, PBL을 우수하게 운영하는 교수들의 수업운영 전략에 대한 연구가 보다 확대되어야 한다. 둘째, PBL을 우수하게 운영하는 교수들과 일반교수들의 운영전략에 관한 비교연구가 수행되어야 한다. 셋째, 조직 차원에서 PBL을 우수하게 운영하는 교수들의 수업운영 전략을 공유할 수 있는 시스템이 지원되어야 한다.

A learning control of DC servomotor using neural network

  • Kawabata, Hiroaki;Yamada, Katsuhisa;Zhong, Zhang;Takeda, Yoji
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1994년도 Proceedings of the Korea Automatic Control Conference, 9th (KACC) ; Taejeon, Korea; 17-20 Oct. 1994
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    • pp.703-707
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    • 1994
  • This paper proposes a method of learning control in DC servomotor using a neural network. First we estimate the pulse transfer function of the servo system with an unknown load, then we determine the best gains of I-PD control system using a neural network. Each time the load changes, its best gains of the I-PD control system is computed by the neural network. And the best gains and its pulse transfer function for the case are stored in the memory. According the increase of the set of gains and its pulse transfer function, the learning control system can afford the most suitable I-PD gains instantly.

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미국 국립보건원 국립암센터 암 보완대체의학 사무국에서 시행하고 있는 최상사례 프로그램에 대한 고찰 (Review of National Institutes of Health NCI's Office of Cancer Complementary and Alternative Medicine Best Case Series Program)

  • 박일동;유화승;이연월;조종관
    • 대한암한의학회지
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    • 제10권1호
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    • pp.47-55
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    • 2005
  • Objectives: The purpose is to advertise the protocol of Best Case Series Programme of National Cancer Institute of USA to korean oriental medical oncologists and researchers Method: We reviewed the submission packet of NCI and related Website and articles. Result and Conclusion: BCS programme is the first step to evaluate the efficacy of complementary and alternative treatment, and to launch the clinical research funded by NCI.

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자동차 타이어 패턴소음 예측에 관한 연구 (A Study on the Pattern Noise Prediction of Automobile Tire)

  • 김병삼
    • 한국공작기계학회논문집
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    • 제14권6호
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    • pp.68-73
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    • 2005
  • Tire manufactures have dealt with noise problem by varying the pitch of the tread. The various formulas for the variations are generally determined differently, however. Often these variations are based on a combination of trial and error, intuition, and economics. Some manufactures have models and analogs to test tread patterns and their variations. These efforts, however practical, do not determine the best variation beforehand or guarantee the best results. For this reason it was felt that a general mathematical approach fur determining the best variation was needed. Moreover, the method should be completely general, easy to use, and sufficiently accurate. This paper discusses a mathematical method called Mechanical Frequency Modulation(MFM) which meets the above requirements. Thus, MFM pertains to computing an irregular time sequence of events so that the resulting excitation spectrum is shaped to a preferred form. The first part of this paper treats the theoretical basis for computing an optimum variation ; the second part discusses experimental results and simulation program which corroborate the theory.

앙상블 학습을 이용한 기업혁신과 경영성과 예측 (Corporate Innovation and Business Performance Prediction Using Ensemble Learning)

  • 안경민;이영찬
    • 한국정보시스템학회지:정보시스템연구
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    • 제30권4호
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    • pp.247-275
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    • 2021
  • Purpose This study attempted to predict corporate innovation and business performance using ensemble learning. Design/methodology/approach The ensemble techniques uses weak learning to create robust learning, which combines several weak models to derive improved performance. In this study, XGboost, LightGBM, and Catboost were used among ensemble techniques. It was compared and evaluated with traditional machine learning methods. Findings The summary of the research results is as follows. First, the type of innovation is expanding from technical innovation to non-technical areas. Second, it was confirmed that LightGBM performed best for radical innovation prediction, and XGboost performed best for incremental innovation prediction. Third, Catboost performed best for firm performance prediction. Although there was no significant difference in predictive power between ensemble techniques, we found that comparative analysis was necessary to confirm better prediction performance.

Uncertainties impact on the major FOMs for severe accidents in CANDU 6 nuclear power plant

  • R.M. Nistor-Vlad;D. Dupleac;G.L. Pavel
    • Nuclear Engineering and Technology
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    • 제55권7호
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    • pp.2670-2677
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    • 2023
  • In the nuclear safety studies, a new trend refers to the evaluation of uncertainties as a mandatory component of best-estimate safety analysis which is a modern and technically consistent approach being known as BEPU (Best Estimate Plus Uncertainty). The major objectives of this study consist in performing a study of uncertainties/sensitivities of the major analysis results for a generic CANDU 6 Nuclear Power Plant during Station Blackout (SBO) progression to understand and characterize the sources of uncertainties and their effects on the key figure-of-merits (FOMs) predictions in severe accidents (SA). The FOMs of interest are hydrogen mass generation and event timings such as the first fuel channel failure time, beginning of the core disassembly time, core collapse time and calandria vessel failure time. The outcomes of the study, will allow an improvement of capabilities and expertise to perform uncertainty and sensitivity analysis with severe accident codes for CANDU 6 Nuclear Power Plant.

Sire Evaluation Using Animal Model and Conventional Methods in Murrah Buffaloes

  • Jain, A.;Sadana, D.K.
    • Asian-Australasian Journal of Animal Sciences
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    • 제13권9호
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    • pp.1196-1200
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    • 2000
  • First lactation records of 683 Murrah buffaloes maintained at National Dairy Research Institute, Karnal, were used for comparing the sire evaluation for age at first calving, first lactation 305-day or less milk yield and first service period. The sires were evaluated using Simple daughters average, Contemporary comparison, Least-squares and BLUP methods. The BLUP evaluations were obtained under single-, two- and three-trait individual animal models. The results revealed that for taking a decision regarding the method of sire evaluation to be used for selecting sires with high breeding values, criteria of the rank correlation could be misleading and comparison of the selected sires is likely to give a veritable picture. The Best Linear Unbiased Prediction method under multi-trait animal model incorporating first lactation milk yield with first service period as a covariable and age at first calving in the model was found to be more efficient and accurate for sire selection in Murrah buffaloes.

광학식 측정방법을 활용한 풍화지반 버럭의 암/토사 구성비율 추정방법 (Rock/Soil proportion estimation using image processing technique)

  • 진규남;김영진;박성욱;조계춘
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2010년도 춘계 학술발표회
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    • pp.1425-1432
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    • 2010
  • In large construction site, although soil conversion factor is so significant to preliminary design, operation design and calculating the cost of construction that it is important to take reasonable estimation and application, the standard of soil conversion factor for weathered ground doesn't clearly suggested yet. So in this study, at first we obtain the image using DSLR - high resolution camera and Laser scanner in the Haeng-Bok city constructin site, then analysis the ratio of soil and rock using various image processing method(Sobel method, Laplace method, Highpass filter, Hue and Saturation analysis). Mutual comparation with the result of image processing analysis and manual segmentation of 5case image in the cad. As a result, best image processing method was different for each case. In case of high propotion of rock, Laplace was best and in case of high propotion of soil, Highpass was best, and mixed case Laplace was best.

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