• Journal of Magnetics
• /
• 제20권2호
• /
• pp.193-200
• /
• 2015

Direct-acting solenoid valves are used in the automotive industry due to their simple structure and quick response in controlling the flow of fluid. We performed an optimization study of response time in order to improve the dynamic performance of a direct-acting solenoid valve. For the optimal design process, we used the commercial optimization software PIAnO, which provides various tools for efficient optimization including design of experiments (DOE), approximation techniques, and a design optimization algorithm. 35 sampling points of computational experiments are performed to find the optimum values of the design variables. In all cases, ANSYS Maxwell electromagnetic analysis software was used to model the electromagnetic dynamics. An approximate model generated from the electromagnetic analysis was estimated and used for the optimization. The best optimization model was selected using the verified approximation model called the Kriging model, and an optimization algorithm called the progressive quadratic response surface method (PQRSM).

• 공업화학
• /
• 제31권2호
• /
• pp.138-146
• /
• 2020

통계학적 실험계획법(DOE)은 수십 년 동안 산업계에서 품질을 개선하기 위해 사용되어온 방법이다. 본 연구에서는 화학공학 분야에서 통계적 실험계획법이 적용된 사례 115건을 검토해 보았다. 모든 사례는 지난 10년간 주요 과학저널에 발표된 내용이다. 적용되는 설계 유형, 실험 규모, 반응 변수에 영향을 미치는 요인 및 수준의 수 및 적용 분야가 분석되었다. 무엇보다 통계학적 실험계획법에 관련된 연구논문이 점차 증가하는 것을 알 수 있었다.

• 한국정밀공학회지
• /
• 제21권7호
• /
• pp.37-45
• /
• 2004

Grinding is a finishing operation of products in various areas. Surface roughness of industrial components obtained in grinding operation is a critical quality measure but is a function of many operating parameters and their interactions. To achieve higher surface roughness and to identify the influence of grinding parameters on surface roughness, it is an ideal situation fer using the design of experiments. This paper presents an successful optimization of grinding conditions and prediction of surface roughness using the design of experiments. From the experimental verification tests, it was observed that this approach was useful as a robust design methodology for grinding operation.

• Computers and Concrete
• /
• 제17권3호
• /
• pp.305-322
• /
• 2016

The work is intended to demonstrate that the loss of bond between concrete and flexural steel which led in recent years a number of flat-slab structures to punching collapse under service loading conditions is also relevant to ultimate limit-state design. It is based on a comparative study of the results obtained from numerical experiments on flat slab-column sub-assemblages. The slabs were designed for punching either in compliance with the EC2 code requirements, which do not allow for such loss of bond, or in accordance with the compressive force-path method which considers the loss of bond between concrete and the flexural reinforcement in tension as the primary cause of punching. The numerical experiments are carried out through the use of a nonlinear finite element analysis package for which, although ample published evidence of its validity exists, additional proof of its suitability for the purposes of the present work is presented.

• 한국공작기계학회논문집
• /
• 제17권4호
• /
• pp.35-41
• /
• 2008

R/In order to satisfy the customer's variant needs for a product quality in recent years, a demand for developing higher precision machining technologies in a lot of application areas such as automobile, cellular phone and semiconductor has been increased more and more. Magnetic abrasive polishing(MAP) process is one of these precision technologies. In this study, to verify the parameters' effect of the MAP process on the surface roughness improvement of the plane and the inclined workpiece, well planned experiments which was called the design of experiments were carried out. Considered polishing factors were spindle speed, supplied current, abrasive type and working gap between the workpiece and the solid tool. As a result, it was seen that the supplied current and the working gap greatly affected the surface roughness improvement.

• 품질경영학회지
• /
• 제24권4호
• /
• pp.156-167
• /
• 1996

D-optimality is used often in design augmentation of mixture experiments. Although such alphabetic criteria provide a valuable foundation for generating designs, they often fail to convey the true nature of the design's support of the fitted model in terms of prediction variance over a region of interest. Thus, a graphical method is proposed to evaluate augmented designs in mixture experiments. This method can be used to evaluate the effect of missing observation and outlier in mixture experiments.

• Computers and Concrete
• /
• 제5권1호
• /
• pp.1-20
• /
• 2008

In this study, the effects and the interactions of water content, SP-binder ratio, and water-binder ratio on the workability performance of concrete were investigated. The experiments were designed based on flatted simplex-centroid experiment design modified from standard simplex-centroid one. The data gotten from the design was used to build the concrete slump model using neural networks. Research reported in this paper shows that a small number of slump experiments can be performed and meaningful data obtained with the experiment design. Such data would be suitable for building slump model using neural networks. The trained network can be satisfactorily used for exploring the effects of the components and their interactions on the workability of concrete. It has found that a high water content and a high SP/b ratio is essential for high workability, but achieving this by increasing these parameters will not in itself guarantee high workability. The w/b played a very important role in producing workability and had rather profound effects; however, the medium value about 0.4 is the best w/b to reach high slump without too much effort on trying to find the appropriate water content and SP/b.

• Journal of the Korean Statistical Society
• /
• 제11권1호
• /
• pp.36-44
• /
• 1982

A new design concept, called axis-slope-rotatability, is presented for the design of experiments with mixtures. This is an analogue of the Box-Hunter (1957) rotatability for second order response surface designs. By choice of design, it is possible to make the variance of the estimated slopes along the component axes constant for all axial points equidistant from the center point of the factor space. This property is called axis-slope-rotatability for mixture experiments. When the Scheffe's second degree polynomial is used, it is shown that some symmetry conditions are sufficient for axis-slope-rotatability. Several designs having this property are illustrated.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1998년도 추계학술대회 논문집 학회본부 B
• /
• pp.493-495
• /
• 1998

Robust design is one method to make manufacturing less sensitive to manufacturing process. Also it is cost effective technique to improve the quality process. This method uses statistically planned experiments to vary settings of important process control parameters. In this paper we apply fuzzy optimization and fuzzy logic system to robust design concept. First a method which uses fuzzy optimization in obtaining optimum settings by measured data from experiments will be presented. Second, fuzzy logic system is made to reduce experiments using experiments results consisted with key control parameter combinations. Then optimum parameter set points are obtained by the descrebed first fuzzy optimization method after prediction the results of each parameter combinations considering each control parameter variations by nonsingleton fuzzy logic system concept.

• 드라이브 ㆍ 컨트롤
• /
• 제12권4호
• /
• pp.8-14
• /
• 2015

A quick-acting hydraulic fuse, which is mainly composed of a poppet, a seat, and a spring, must be designed to minimize the leaked oil volume during fuse operation on a line rupture. The optimal design parameters of a quick-acting hydraulic fuse were searched using the design of experiments method and the complex method. First, the $L_{50}(5^4)$ orthogonal array is used to find the robust minimum point among the 625 points of design variables. The search range can then be narrowed around the robust minimum point. Second, the $L_{25}(5^4)$ orthogonal array is used to obtain the variations of the design variables in the narrowed search range. The variations of design variables are used to set the structure of a polynomial equation representing the leakage oil volume of the quick-acting hydraulic fuse. The least squares method is then applied to obtain the coefficients of polynomial equation. Finally, the complex method is used to find the optimal design parameters where the objective function is described by the polynomial equation.