• 제목/요약/키워드: Crossover study

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강화학습을 이용한 진화 알고리즘의 성능개선에 대한 연구 (A Study on Performance Improvement of Evolutionary Algorithms Using Reinforcement Learning)

  • 이상환;심귀보
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 1998년도 추계학술대회 학술발표 논문집
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    • pp.420-426
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    • 1998
  • Evolutionary algorithms are probabilistic optimization algorithms based on the model of natural evolution. Recently the efforts to improve the performance of evolutionary algorithms have been made extensively. In this paper, we introduce the research for improving the convergence rate and search faculty of evolution algorithms by using reinforcement learning. After providing an introduction to evolution algorithms and reinforcement learning, we present adaptive genetic algorithms, reinforcement genetic programming, and reinforcement evolution strategies which are combined with reinforcement learning. Adaptive genetic algorithms generate mutation probabilities of each locus by interacting with the environment according to reinforcement learning. Reinforcement genetic programming executes crossover and mutation operations based on reinforcement and inhibition mechanism of reinforcement learning. Reinforcement evolution strategies use the variances of fitness occurred by mutation to make the reinforcement signals which estimate and control the step length.

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전류제어형 DC-DC컨버터의 안정도 향상에 관한 연구 (A Study on the stability improvement of current-mode controlled DC-DC Converter)

  • 김철진;송요창
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 추계학술대회 논문집 학회본부 B
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    • pp.365-367
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    • 2000
  • Recently, the power supply equipments have tendency to take multiple feedback loop paths. In this paper, the state space averaging technique is applied for the analysis of flyback type current mode control circuit. We made real converter for the gurantee of stable output characteristic and proper design of feedback circuit. The validity of proposed method is verified from test results. The improvement of stability is confirmed by sinusoidal signal injection method with isolated transformer. It is known that phase margin is sufficient and gain crossover frequency $f_c$ is nearly 1/5 of switching frequency $f_s$ from the experimental result with frequency response analyzer.

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진화 신경회로망 제어기를 이용한 도립진자 시스템의 안정화 제어에 관한 연구 (A Study on Stabilization Control of Inverted Pendulum System using Evolving Neural Network Controller)

  • 김민성;정종원;성상규;박현철;심영진;이준탁
    • 한국마린엔지니어링학회:학술대회논문집
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    • 한국마린엔지니어링학회 2001년도 춘계학술대회 논문집
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    • pp.243-248
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    • 2001
  • The stabilization control of Inverted Pendulum(IP) system is difficult because of its nonlinearity and structural unstability. Thus, in this paper, an Evolving Neural Network Controller(ENNC) without Error Back Propagation(EBP) is presented. An ENNC is described simply by genetic representation using an encoding strategy for types and slope values of each active functions, biases, weights and so on. By an evolutionary programming which has three genetic operation; selection, crossover and mutation, the predetermine controller is optimally evolved by updating simultaneously the connection patterns and weights of the neural networks. The performances of the proposed ENNC(PENNC) are compared with the ones of conventional optimal controller and the conventional evolving neural network controller(CENNC) through the simulation and experimental results. And we showed that the finally optimized PENNC was very useful in the stabilization control of an IP system.

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Anti-lipopolysaccharide antibody mitigates ruminal lipopolysaccharide release without acute-phase inflammation or liver transcriptomic responses in Holstein bulls

  • Mizuguchi, Hitoshi;Kizaki, Keiichiro;Kimura, Atsushi;Kushibiki, Shiro;Ikuta, Kentaro;Kim, Yo-Han;Sato, Shigeru
    • Journal of Veterinary Science
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    • 제22권3호
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    • pp.34.1-34.7
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    • 2021
  • Anti-lipopolysaccharide (LPS) antibody administration has the potential benefits of neutralizing and consequently controlling rumen-derived LPS during subacute ruminal acidosis. Four Holstein bulls were used in this crossover study with a 2-week wash-out period. Anti-LPS antibody (0 or 4 g) was administered once daily for 14 days. Significantly lower ruminal LPS and higher 1-h mean ruminal pH were identified in the 4 g group. However, blood metabolites, acute-phase proteins, cytokines, and hepatic transcriptomes were not different between the two groups. Therefore, anti-LPS antibody administration mitigated ruminal LPS release and pH depression without accompanying responses in acute-phase inflammation or hepatic transcriptomic expression.

Effect of Kinesiolology taping and Posture Stabilizing Exercise on Pain, Craniovertebral Angle, Proprioception in Adults with Forward Head Posture

  • Choi, Junghyun
    • 국제물리치료학회지
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    • 제10권3호
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    • pp.1862-1867
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    • 2019
  • Background: The importance of postural stabilization and cervical mobilization in subjects with pain from the anterior head posture is drawing more attention. However, studies on head and neck stabilizing intervention after mobilization are lacking. Objective: To examine the effects of Kinesiotaping and posture setting exercise on forward head posture (FHP). Design: Crossover Study Design Methods: The subjects were 17 male and female college students in their 20s with FHP. They were randomized into the Kinesiology taping group (KTG) with 9 subjects and posture stabilizing exercise group (PSEG) with 8 subjects. The intervention was conducted for 4 weeks, and changes in pain, craniovertebral angle (CVA), and proprioception were observed before and after intervention. Results: Pain was significantly reduced in the KTG and PSEG both before and after intervention. CVA and proprioception were significantly increased only in the PSEG. The differences in CVA and proprioception between the two groups were significant. Conclusions: These findings suggest that the application of posture setting exercise could decrease pain, proprioceptive error and increase CVA on FHP.

Bioequivalence Assessment of Shinpoong "$\textrm{Dompi}^{?}$" Tablets Containing Domperidone Maleate in Healthy Korean Volunteers

  • Yoo , An-Na;Kim, Sung-Chul;Lee, Kyung-Hee;Park, Jong-Min;Nam, Doo-Hyun
    • 대한약학회:학술대회논문집
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    • 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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    • pp.242.1-242.1
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    • 2003
  • The bioequivalence of two tablet formulations of 12.72 mg domperidone maleate (Shinpoong "$\textrm{Dompi}^{?}$" tablets vs. Janssen Korea "$\textrm{Dompi}^{?}$" tablets) was assessed in healthy Korean volunteers after oral administration in a randomized crossover study. Blood samples were collected at specified time intervals, and plasma concentration was measured as the amount of domperidone base using a validated HPLC method. The pharmacokinetic parameters of $AUC_{0{\longrightarrow}48}$, $C_{max}$, $T_{max}$$t\frac{1}{2}$ were determined from plasma concentration-time profile of two formulations. (omitted)

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The Effect of Chewing Difficulty on Osteoarthritis in Korean Adults: The 8th Korean National Health and Nutrition Examination Survey (KNHANESVIII-1, 2), (2019~2020)

  • Nam, Ji-Ae;Choi, Mi-Sook;Lee, Jung-Hwa
    • 대한의생명과학회지
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    • 제28권3호
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    • pp.178-185
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    • 2022
  • The purpose of this study was to analyze the effect of chewing difficulty on osteoarthritis in Korean adults. Data from the National Health and Nutrition Examination Survey for two years from 2019 to 2020. The collected data were analyzed using the SPSS (21.0) program using composite samples, and the mean crossover analysis and logistic return analysis were performed. An analysis of the effects of chewing difficulty on osteoarthritis in korean adults showed that those with chewing difficulty had a 2.02 fold higher risk of osteoarthritis (95%CI=1.56~2.42) and a statistically significant difference (P<0.05). The association between the chewing difficulty on osteoarthritis could be confirmed, and measures improve of the oral health and preventing osteoarthritis should be prepared.

대기오염의 건강 영향 평가를 위한 역학연구 설계 및 방법론 (Epidemiologic Methods and Study Designs for Investigating Adverse Health Effects of Ambient Air Pollution)

  • 김호;이종태
    • Journal of Preventive Medicine and Public Health
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    • 제34권2호
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    • pp.119-126
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    • 2001
  • Air pollution epidemiologic studies are intrinsically difficult because the expected effect size at general environmental levels is small, exposure and misclassification of exposure are common, and exposure is not selective to a specific pollutant. In this review paper, epidemiologic study designs and analytic methods are described, and two nationwide projects on air pollution epidemiology are introduced. This paper also demonstrates that possible confounding issues in time-series analysis can be resolved and the impact on the use of data from ambient monitoring stations may not be critical. In this paper we provide a basic understanding of the types of air pollution epidemiologic study designs that be subdivided by the mode of air pollution effects on human health (acute or chronic). With the improvements in the area of air pollution epidemiologic studies, we should emphasize that elaborate models and statistical techniques cannot compensate for inadequate study design or poor data collection.

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A Longitudinal Study on Adolescent's Community Consciousness and Life Satisfaction using Autoregressive Cross-lagged Model

  • Kim, Hyun-Joo;Park, Hyun-Sun;Park, Hwie-Seo
    • 한국컴퓨터정보학회논문지
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    • 제24권6호
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    • pp.175-182
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    • 2019
  • This study aims to identify causal variables by examining the mutual influences of community consciousness and life satisfaction. We used some data of KCYPS. A longitudinal study of 1952 adolescents selected as a sample was conducted using the Aautoregressive crossover delay model. The results of this study are as follows: First, it showed that life satisfaction is consistently affecting the later life satisfaction with the passage of time. Second, community consciousness showed that the previous community consciousness has a constant influence on the subsequent community consciousness as time passes. Third, the effect of previous life satisfaction on community consciousness was significant. Therefore, the cross-delay effect of life satisfaction on community awareness was stable with time. In other words, life satisfaction level was a causal variable that takes precedence over community consciousness, and the higher the life satisfaction of the previous time, the higher the level of community consciousness in the future. Fourth, the cross-delay effect of community consciousness on life satisfaction was not significant because community consciousness at previous time had no meaningful effect on life satisfaction at later time, so consciousness of community at previous time affects life satisfaction. This study provided some implications basing on this results.

뮤코펙트 정(염산암브록솔 30 mg)에 대한 암브렉트 정의 생물학적 동등성 (Bioequivalence of AmbrectTM Tablet to MucopectTM Tablet (Ambroxol hydrochloride 30 mg))

  • 유정연;정선경;최미희;한상범;이경률;이희주
    • Journal of Pharmaceutical Investigation
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    • 제33권3호
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    • pp.215-221
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    • 2003
  • A bioequivalence study of $Ambrect^{TM}$ tablets (Dong Wha Pharm. Ind. Co., Ltd.) to $Mucopect^{TM}$ tablets (Boehringer Ingelheim Korea, Ltd.) was conducted according to the guideline of Korea Food and Drug Administration (KFDA). Twenty four healthy male Korea volunteers received each medicine at the ambroxol hydrochloride dose of 30 mg in a $2{\times}2$ crossover study. There was a one-week wash out period between the doses. Plasma concentrations of ambroxol were monitored by a high-performance liquid chromatography for over a period of 24 hours after the administration. $AUC_t$ (the area under the plasma concentration-time curve from time zero to 24 hr) was calulated by the linear trapezoidal rule method. $C_{max}$ (maximum plasma drug concentration) and $T_{max}\;(time\;to\;reach\;C_{max})$ were compiled from the plasma concentration-time data. Analysis of variance was carried out using logarithmically transformed $AUC_t\;and\;C_{max}$. No significant sequence effect was found for all of the bioavailability parameters indicating that the crossover design was properly performed. The 90% confidence intervals of the $AUC_t$ ratio and the $C_{max}$ ratio for $Ambrect^{TM}/Mucopect^{TM}$ were 0.89-1.01 and 0.89-1.02, respectively. These values were within the acceptable bioequivalence intervals of 0.80-1.25. Thus, our study demonstrated the bioequivalence of $Ambrect^{TM}\;and\;Mucopect^{TM}$ with respect to the rate and extent of absorption.