• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.1005-1010
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• 2004

The structural optimization has been carried out in the continuous design space or in the discrete design space. Generally, available designs are discrete in design practice. But methods for discrete variables are extremely expensive in computational cost. In order to overcome this weakness, an iterative optimization algorithm was proposed for design in the discrete space, which is called as a sequential algorithm using orthogonal arrays (SOA). We focus to verify the fact that the local solution can be obtained throughout the optimization with this algorithm. The local solution is defined in discrete design space. Then the search space, which is the set of candidate values of each design variables formed by the neighborhood of current design point, is defined. It is verified that a local solution can be founded by moving sequentially the search space. The SOA algorithm has been applied to problems such as truss type structures. Then it is confirmed that a local solution can be obtained using the SOA algorithm

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집A
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• pp.708-713
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• 2000

The design of experiment(DOE) is getting more attention in the engineering community since it is easy to understand and apply. Recently, engineering designers are adopting DOE with orthogonal arrays when they want to design products in a discrete design space. In this research, a design flow with orthogonal arrays is defined fur structural design according to the general DOE. The design problem is defined as a general structural optimization problem. Sensitivity information is evaluated by the analysis of variance(ANOVA), and an optimum design is determined from analysis of means(ANOM). Interactions between design variables are investigated to achieve additivity which should be valid in DOE. When strong interactions exit, a method is proposed. Some methods to consider the problem are suggested.

• 대한기계학회논문집A
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• 제24권12호
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• pp.2952-2962
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• 2000

The design of experiment(DOE) is getting more attention in the engineering community since it is easy to understand and apply. Recently, engineering designers are adopting DOE with orthogonal arrays when they want to design products in a discrete design space. In this research, a design flow with orthogonal arrays is defined for structural design according to the general DOE. The design problem is defined as a general structural optimization problem. Sensitivity information is evaluated by the analysis of variance(ANOVA), and an optimum design is determined from analysis of means(ANOM). Interactions between design variables are investigated to achieve additivity which should be valid in DOE. When strong interactions exit, a method is proposed. Some methods to consider the problem are suggested.

• 한국연초학회지
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• 제5권1호
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• pp.49-56
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• 1983

• 한국초전도저온공학회:학술대회논문집
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• 한국초전도저온공학회 2002년도 학술대회 논문집
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• pp.149-152
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• 2002

SrZrO3 resistive oxide barriers on Ag sheathed Bi2223 tapes prepared by the sol-gel and dip coating method were evaluated with an aid of Taguchi method and orthogonal arrays to elucidate the effects of experimental parameters, such as ratio of starting solution, amount of additives, and heat treatment temperature and time on the properties of the thin films. Six experimental parameters were selected and then Ll8(21x37) orthogonal arrays were constructed. Finally, SEM and XRD results were related to signal to noise (S/N) ratio to evaluate the optimized experimental condition.

• 한국소음진동공학회논문집
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• 제15권10호
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• pp.1123-1130
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• 2005

We propose an optimal design to improve the capacity by reducing the noise of the intake system. The length and radius of each component of the current Intake system are selected as control factors. We accept the output from computer simulator with orthogonal arrays. Then, the Kriging estimates are computed. From this, we exploit the optimal design of the intake system by adapting simulated annealing. From the results of this optimal design, we conclude that Kriging method with the orthogonal arrays is the efficient method for Design and Analysis of Computer Experiments and we propose the useful results for the low noise intake system.

• 한국기계가공학회지
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• 제10권6호
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• pp.70-76
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• 2011

This paper presents an optimization procedure for reducing warpage of injection molded part by using a volumetric shrinkage deviation as an objective function. A design of experiments based on orthogonal arrays was used in the optimization procedure, and the entire optimization was performed through a two stage process - a preliminary experimentation and a principal experimentation. Proposed optimization method was applied to the design of a CPU-base part in computer. With the moderate number of experiments, an optimal molding condition for uniform distribution of volumetric shrinkage was obtained, as a result, the warpage of the molded part was significantly reduced.

• 재무관리논총
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• 제3권2호
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• pp.267-279
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• 1996

The prediction of future demand is a vital task in managing business operations. To this end, traditional approaches often focused on statistical techniques such as exponential smoothing and moving average. The need for better accuracy has led to nonlinear techniques such as neural networks and case based reasoning. In addition, experimental design techniques such as orthogonal arrays may be used to assist in the formulation of an effective methodology. This paper investigates a multistrategy approach involving neural nets, case based reasoning, and orthogonal arrays. Neural nets and case based reasoning are employed both separately and in combination, while orthoarrays are used to determine the best architecture for each approach. The comparative evaluation is performed in the context of an application relating to the prediction of Treasury notes.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 추계학술대회논문집
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• pp.385-388
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• 2005

Finite element method and Taguchi method were used to reduce the floor impact vibration of the reinforced concrete slab in the apartment buildings. At first, experimental results show that sound peak components to influence the rating of floor impact sound insulation were coincident with natural frequencies of the reinforced concrete slab, and there is a high linear relation between floor impact vibration and sound. The tables of orthogonal arrays were used for finite element analysis with 5 factors related to slab shape parameters and its results were analyzed by statistical method. The most effective factor to reduce the floor impact vibration was the length of living/kitchen room and the floor impact vibration was predicted by 30% reduction in the acceleration peak by the optimal design values of the factors.

• 한국염색가공학회지
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• 제2권1호
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• pp.14-20
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• 1990

The cotton fabrics were treated with formaldehyde in the presence of zinc nitrate catalyst and urea. The effects of HCHO concentration, urea concentration, catalyst ratio, cure time and cure temperature on the physical properties of fabrics were studied. Cotton fabric finished with HCHO and urea had the lower tensile strength and tear strength than untreated one. These strength losses resulted from tighter oxymethylene crosslinks. The enhanced wrinkle recovery for fabric treated with formaldehyde in the presence of urea was indicative of the formation of urea-formaldehyde polymer. These experimental conditions were set up according to table of orthogonal arrays.