• 제목/요약/키워드: Variable parameters

검색결과 1,721건 처리시간 0.033초

부하와 강도가 대수정규분포를 하는 신뢰성 설계에서 최적화에 관한 연구(II) (Optimization in Reliability Design with Lognormally Stress and Lognormally Strength)

  • 김복만;황의철
    • 산업경영시스템학회지
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    • 제13권22호
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    • pp.25-34
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    • 1990
  • This paper is to maximize the reliability subject to certain constraints on amounts of resources available for control of the parameters. The lagrange multiplier method is used to optimize t-th lognormal stress-lognormal strength problem. This optimization problem can be reduced to a search problem in one variable. A numerical example is presented to illustrate the optimization problem.

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가변구조 제어기를 이용한 인공위성의 자세제어 (Attitude Control of Satelite by Variable Structure Ccontroller)

  • 조윤철;박수홍;조겸래
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1990년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 26-27 Oct. 1990
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    • pp.463-468
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    • 1990
  • A VSC law is derived for the attitude control of an orbiting spacecraft in the presence of disturbance and parameters variation using reaction jets. The switching surface was chosen to be a linear function of tracking error, its derivative and integral. Simulation results are presented to show that in the closed-loop system, precise attitude control is accomplished in spite of uncertainty in the system.

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불확실한 수명주기의 제품에서의 경제적 주문량 모형 (An Economic Order Quantity Model under Random Life Cycle)

  • 윤원영;문일경
    • 대한산업공학회지
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    • 제19권1호
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    • pp.73-77
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    • 1993
  • This paper considers an Economic Order Quantity Model under random life cycle. It is assumed that the life cycle of the product is unknown; a random variable. Three cost parameters are considered; ordering cost, inventory carrying cost and salvage cost. Expected total cost is the optimization criterion. We show that the optimal cycle length is unique and finite, and present a simple line search method to find an optimal cycle length.

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독립변수의 측정오차가 예측에 미치는 영향을 평가하기 위한 기준개발 (Development of a Criterion for Assessing the Influence of the Measurement Errors in the Independent Variables on Prediction)

  • 변재현
    • 대한산업공학회지
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    • 제19권1호
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    • pp.39-46
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    • 1993
  • In developing a multiple regression relationship, independent variables are frequently measured with error. For these situations the problem of estimating unknown parameters has been extensively discussed in the literature while little attention has been given to the prediction problem. In this paper a criterion is developed for assessing the severeness of measurement errors in each independent variable on the predicted values. Using the developed criterion we can present a guideline as to which measurement error should be controlled for a more accurate prediction. Proposed methods are illustrated with a standard data system in work measurement.

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Nonlinear Behavior in Love Model with Discontinuous External Force

  • Bae, Youngchul
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제16권1호
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    • pp.64-71
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    • 2016
  • This paper proposes nonlinear behavior in a love model for Romeo and Juliet with an external force of discontinuous time. We investigated the periodic motion and chaotic behavior in the love model by using time series and phase portraits with respect to some variable and fixed parameters. The computer simulation results confirmed that the proposed love model with an external force of discontinuous time shows periodic motion and chaotic behavior with respect to parameter variation.

로봇 매니퓰레이터를 위한 퍼지 이동 슬라이딩 모드 제어 (Fuzzy moving sliding mode control for robotic manipulators)

  • 한태열;전경한;최봉열
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.348-348
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    • 2000
  • In this paper, we present a fuzzy moving sliding mode control for two-degrree-of-freedom robotic manipulator. 17he sliding surface parameters are designed by fuzzy inference. The proposed sliding mode control makes the error always remain on the surface from beginning and therefore, the system is insensitive to system uncertaintics and external disturbances. Simulation results show the effectiveness of proposed scheme.

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다수의 퍼지규칙을 이용한 가변유압시스템의 강건제어 (Robust Control of Variable Hydraulic System using Multiple Fuzzy Rules)

  • 양경춘;안경관;이수한
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.134-134
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    • 2000
  • A switching control using multiple gains in the fuzzy rule is newly proposed for an abruptly changing hydraulic servo system. The proposed scheme employs fuzzy PID control, where modified input parameters are used, and LVQNN(Learning Vector Quantization Neural Network) as a switching controller (supervisor). Simulation and experimental studies have been carried out to validate and illustrate the proposed controller.

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Basic rheology of dermal filler

  • Choi, Moon Seop
    • Archives of Plastic Surgery
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    • 제47권4호
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    • pp.301-304
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    • 2020
  • Dermal injectables are the most popular material for facial enhancement, including volumizing and wrinkle correction. However, although hyaluronic acid is the most common component of dermal injectables, the character of hyaluronic acid products is quite variable. These materials can be described in terms of their viscoelastic properties using four parameters. In this article, the author would like to describe these properties in detail. Although many physicians consider this material to be convoluted, thoroughly understanding the characteristics of various injectables enables us to tailor procedures accordingly and to enhance the final results.

On Perturbed Symmetric Distributions Associated with the Truncated Bivariate Elliptical Models

  • Kim, Hea-Jung
    • Communications for Statistical Applications and Methods
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    • 제15권4호
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    • pp.483-496
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    • 2008
  • This paper proposes a class of perturbed symmetric distributions associated with the bivariate elliptically symmetric(or simply bivariate elliptical) distributions. The class is obtained from the nontruncated marginals of the truncated bivariate elliptical distributions. This family of distributions strictly includes some univariate symmetric distributions, but with extra parameters to regulate the perturbation of the symmetry. The moment generating function of a random variable with the distribution is obtained and some properties of the distribution are also studied. These developments are followed by practical examples.

직접 STR을 이용한 웹 이송 시스템에서의 장력제어 (Tension Control in Web Transport System using Direct Self-tuning Regulator)

  • 오기석;권태종;한창수;강남기;조형진
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1996년도 추계학술대회 논문집
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    • pp.236-242
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    • 1996
  • The purpose of this paper is to study the tension control in a web transport system. Direct self-tuning regulator method was applied to tension controller and variable-gain PID control algorithm was applied to web speed controller. The designed controllers compensated for the time-varying parameters and tracked reference tension in process speed changing. The simulation shows that direct STR tension controller improves tension control performance in comparison with other controllers.

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