• Title/Summary/Keyword: multivariate optimization

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Application of Multivariate Adaptive Regression Spline-Assisted Objective Function on Optimization of Heat Transfer Rate Around a Cylinder

  • Dey, Prasenjit;Das, Ajoy K.
    • Nuclear Engineering and Technology
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    • v.48 no.6
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    • pp.1315-1320
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    • 2016
  • The present study aims to predict the heat transfer characteristics around a square cylinder with different corner radii using multivariate adaptive regression splines (MARS). Further, the MARS-generated objective function is optimized by particle swarm optimization. The data for the prediction are taken from the recently published article by the present authors [P. Dey, A. Sarkar, A.K. Das, Development of GEP and ANN model to predict the unsteady forced convection over a cylinder, Neural Comput. Appl. (2015) 1-13]. Further, the MARS model is compared with artificial neural network and gene expression programming. It has been found that the MARS model is very efficient in predicting the heat transfer characteristics. It has also been found that MARS is more efficient than artificial neural network and gene expression programming in predicting the forced convection data, and also particle swarm optimization can efficiently optimize the heat transfer rate.

A HIGHER ORDER ITERATIVE ALGORITHM FOR MULTIVARIATE OPTIMIZATION PROBLEM

  • Chakraborty, Suvra Kanti;Panda, Geetanjali
    • Journal of applied mathematics & informatics
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    • v.32 no.5_6
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    • pp.747-760
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    • 2014
  • In this paper a higher order iterative algorithm is developed for an unconstrained multivariate optimization problem. Taylor expansion of matrix valued function is used to prove the cubic order convergence of the proposed algorithm. The methodology is supported with numerical and graphical illustration.

A Study on Process Capability Index using Loss Function Under the Muli-Attribute Conditions (다특성을 고려한 상황하에서의 공정능력지수에 관한 연구)

  • Kim Youn Hee;Kim Soo Youl;Park Myoung Kyu
    • Proceedings of the Safety Management and Science Conference
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    • 2005.05a
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    • pp.503-521
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    • 2005
  • Process capability indices are widely used in industries and quality assurance system. When designing the parameter on the multiple quality characteristics, there has been a study for optimization of problems, but there has been few former study on the possible conflicting phenomena in considertion of the correlations among the characteristics. To solve the issue on the optimal design for muliple quality characteristics, the study propose the expected loss function with cross-product terms among the characteristics and derived range of the coefficients of terms. Therefore, the analysis have to be required a multivariate statistical technique. This paper introduces to multivariate capability indices and then selects a multivariate process capability index incorporated both the process variation and the process deviation from target among these indices under the multivariate normal distribution. We propose a new multivariate capability index $MC_{pm}^{++}$ using quality loss function instead of the process variation and this index is compared with the proposed indices when quality characteristics are independent and dependent of each other,

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A Study on Multiple Characteristics Process Capability Index using Expected Loss Function (기대손실함수를 이용한 다특성치 공정능력지수에 관한 연구)

  • Kim Su Yeol;Jo Yong Uk;Park Myeong Gyu
    • Proceedings of the Safety Management and Science Conference
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    • 2004.11a
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    • pp.69-79
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    • 2004
  • Process capability indices are widely used in industries and quality assurance system. When designing the parameter on the multiple quality characteristics, there has been a study for optimization of problems, but there has been few former study on the possible conflicting phenomena in considertion of the correlations among the characteristics. To solve the issue on the optimal design for multiple quality characteristics, the study propose the expected loss function with cross-product terms among the characteristics and derived range of the coefficients of terms. Therefore, the analysis have to be required a multivariate statistical technique. This paper introduces to multivariate capability indices and then selects a multivariate process capability index incorporated both the process variation and the process deviation from target among these indices under the multivariate normal distribution. We propose a new multivariate capability index $MC_{pm}^{++}$ using quality loss function instead of the process variation and this index is compared with the proposed indices when quality characteristics are independent and dependent of each other.

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Design Centering by Genetic Algorithm and Coarse Simulation

  • Jinkoo Lee
    • Korean Journal of Computational Design and Engineering
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    • v.2 no.4
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    • pp.215-221
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    • 1997
  • A new approach in solving design centering problem is presented. Like most stochastic optimization problems, optimal design centering problems have intrinsic difficulties in multivariate intergration of probability density functions. In order to avoid to avoid those difficulties, genetic algorithm and very coarse Monte Carlo simulation are used in this research. The new algorithm performs robustly while producing improved yields. This result implies that the combination of robust optimization methods and approximated simulation schemes would give promising ways for many stochastic optimizations which are inappropriate for mathematical programming.

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Tolerance Optimization with Markov Chain Process (마르코프 과정을 이용한 공차 최적화)

  • Lee, Jin-Koo
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.13 no.2
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    • pp.81-87
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    • 2004
  • This paper deals with a new approach to tolerance optimization problems. Optimal tolerance allotment problems can be formulated as stochastic optimization problems. Most schemes to solve the stochastic optimization problems have been found to exhibit difficulties in multivariate integration of the probability density function. As a typical example of stochastic optimization the optimal tolerance allotment problem has the same difficulties. In this stochastic model, manufacturing system is represented by Gauss-Markov stochastic process and the manufacturing unit availability is characterized for realistic optimization modeling. The new algorithm performed robustly for a large deviation approximation. A significant reduction in computation time was observed compared to the results obtained in previous studies.

Shape Optimization of High Voltage Gas Circuit Breaker Using Kriging-Based Model And Genetic Algorithm (크리깅 메타모델과 유전자 알고리즘을 이용한 초고압 가스차단기의 형상 최적 설계)

  • Kwak, Chang-Seob;Kim, Hong-Kyu;Cha, Jeong-Won
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.62 no.2
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    • pp.177-183
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    • 2013
  • We describe a new method for selecting design variables for shape optimization of high-voltage gas circuit breaker using a Kriging meta-model and a genetic algorithm. Firstly we sample balance design variables using the Latin Hypercube Sampling. Secondly, we build meta-model using the Kriging. Thirdly, we search the optimal design variables using a genetic algorithm. To obtain the more exact design variable, we adopt the boundary shifting method. With the proposed optimization frame, we can get the improved interruption design and reduce the design time by 80%. We applied the proposed method to the optimization of multivariate optimization problems as well as shape optimization of a high - voltage gas circuit breaker.

APPLICATION OF SIMULATED ANNEALING FOR THE MATHEMATICAL MODELLING OF IMMUNE SYSTEMS

  • Lee, Kwon-Soon;Lee, Young-Jin;Chung, Hyeng-Hwan
    • Proceedings of the KOSOMBE Conference
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    • v.1992 no.05
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    • pp.129-132
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    • 1992
  • Cellular kinetics formulate the basis of tumor immune system dynamics which may be synthesized mathematically as cascades of bilinear systems which are connected by nonlinear dynamical terms. In this manner, a foundation for the control of syngeneic tumors is presented. We have analyzed the mechanisms of controlling the infiltration of lymphocytes into tumor tissues. Simulated anneal ins, a general-purpose method of multivariate optimization, is applied to combinatorial optimization, which is to find the minimum of a given function depending on many parameters. We compare the results of the different methods including the global optimization algorithm, known as simutated annealing.

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Simultaneous Optimization of Multiple Responses Using Weighted Desirability Function

  • Park, Sung-Hyun;Park, Jun-Oh
    • Journal of Korean Society for Quality Management
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    • v.25 no.1
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    • pp.56-68
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    • 1997
  • The object of multiresponse optimization is to determine conditions on hte independent variables that lead to optimal or nearly optimal values of the response variables. Derringer and Suich (1980) extended Harrington's (1965) procedure by introducing more general transformations of the response into desirability functions. The core of the desirability a, pp.oach condenses a multivariate optimization into a univariate one. But because of the subjective nature of this a, pp.oach, inexperience on the part of the user in assessing a product's desirability value may lead to inaccurate results. To compensate for this defect, a weighted desirability function is introduced which takes into consideration the vriances of the responses.

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