• Bulletin of the Korean Chemical Society
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• 제12권1호
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• pp.52-57
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• 1991

To find optimum conditions necessary in converting physical properties of any resin into those of others, eleven kinds of HIPS (High-Impact Polystyrene) resins were prepared. First physical properties of eleven samples divided into three groups are analyzed by a torque rheometer (named Plasti-Corder, Model No.: PLD 651) and GPC (Gel Permeation Chromatography), and then optimum conditions on conversion among samples are obtained by calculation from computer simulation so that any sample subjected to each group can show physical properties of other samples in its group. Even though the kind of plasticizer of any sample is different with others in its group, once optimum conditions on conversion among samples are met, it is found that physical properties of any sample are identical or similar to those of others in each group.

• 한국식생활문화학회지
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• 제27권1호
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• pp.57-65
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• 2012

The purpose of this study was to determine the optimum amounts of vegetables to use for flavoring chicken head soup base. The effects of the amounts of ginger and onion on the sensory properties of chicken head soup base were examined, and the optimum amounts were determined using response surface methodology. Sensory properties that were evaluated were yellowness, turbidity, bloody flavor, chicken-brothiness, organ meat-like flavor, and sweet taste. The increased amounts of ginger and onion led to a decrease in bloody flavor and organ meat-like flavor. The optimum levels of ginger and onion were determined to be 40g and 50g, respectively. Chicken head soup base prepared with optimum amounts of vegetables contained more arginine, tryptophan, inosine monophosphate (IMP), and hypoxanthine than plain chicken head soup base. It also had less hexanal, which is related to fat rancidity.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 추계학술대회논문집 I
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• pp.419-426
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• 2001

Industrial products determined by fixed size posses definite limits variety by manufacture tolerance in existence. The optimum value solved by deterministic approaches do not account of tolerance bands of design variables and material properties. If we examine optimum value considering tolerance bands of design variables and material properties, it might be useless, owing to exist infeasible region. We have two ways to prevent being useless value. The one is to minimize tolerance band, the other is to consider tolerance band in optimum design. The former needed more accuracy during manufacturing process require higher production cost, the letter is more appropriate to consider tolerance band. In this research, we consider the tolerance bands of all variables, which might have the tolerance bands used in the problem, based on optimum value of deterministic approaches. Orthogonal arrays are used to minimize the number of trial. Tolerance bands are supposed discretionary according to design variable. Appropriateness suggested by this research is examined through two examples. Mathematical problem is investigated only in terms of tolerance bands of design variables, and cantilever beam problem is explained through tolerance bands of design variable, material properties and loading conditions. It is proved that values from the presented method are satisfactory for tolerance bands of variables.

• 한국항행학회논문지
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• 제12권5호
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• pp.412-419
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• 2008

유전자 알고리즘은 효과적으로 최적의 해를 구하는 기법이나 진화연상산자의 선정에 따라 조기에 국부 최적해에 고착되어 전역 최적해로의 탐색을 어렵게 하는 문제점을 가지고 있다. 본 논문에서는 국부 최적해로 수렴하게 되는 원인을 분석하고, 국부 최적해에서 벗어나 전역 최적해로의 천이가 가능하도록 하는 방법을 제안하였다. 본 논문에서 사용한 방법은 평균 해밍거리에 따라 진화연산자를 가변시키는 방법으로서 국부 최적해에 고착되지 않도록 유전자에 다양성을 부여하여 지속적으로 모집단의 진화 특성을 유지하는 방법이다. 제안된 방법은 시뮬레이션을 통하여 효용성을 입증하였다.

• 한국염색가공학회지
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• 제6권4호
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• pp.62-71
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• 1994

The weighting increase varies with the condition of tannin-weight process and effects dyeability and physical properties of silk. The purpose of this study is to investigate the optimum condition of tannin-weighting process of silk and the effect of tannin-weighting process on dyeability and properties of silk. The methods of this study are first to examine the change according to the variables such as, weight increase of silk, temperature(30, 50, 70, 80, 9$0^{\circ}C$), time(30, 60, 120, 180, 240, 300min), tannin concentration(3, 5, 10, 20, 30g/l) in order to present the optimum condition, sencond to examine the change of the properties such as surface morphology, strength, elongation, mechanical values, dyeing condition, Basic and Acid dye absorption on silk which are tannin-weight processed in the optimum condition.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계 학술발표회 논문집(II)
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• pp.621-624
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• 2006

This paper presents a novel optimum technique for optimum mix-proportion using database-based prediction model of material properties for an object function or a constraint condition. The proposed technique provides high reliability of results introducing effective region model, which assesses whether the prediction model is effective or not, in optimization process. In order to validate the proposed technique, a genetic algorithm was adopted as a optimum technique, and an artificial neural network was adopted as a prediction model for material properties and as a model for assessing effective region. The mix-proportion obtained from the proposed technique is more reasonable than that obtained from a general optimum technique.

• The International Journal of Costume Culture
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• 제8권1호
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• pp.23-31
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• 2005

Mechanical properties and hand evaluation of wool/acrylic(W/A) blend knits were conducted before and after repeated washing to get the optimum W/A blending ratio, which could help achieve the optimum mechanical and hand properties of the knits. The five test fabrics using the yarns with different W/A blending ratios($\%$), 100/0, 70/30, 50/50, 30/70, 0/100, were knitted. The fabrics were washed by a rotating drum type washing machine. Then, objective mechanical and hand properties were evaluated by KES-FB, Kawabata evalution system for fabric. The results are as follows: there was no change in the hand value of the knitted fabric with the W/A-blended yarn caused by the change in the blending ratio before washing. After washing, however, the increase of acrylic's blending rate caused the bending property to decrease proportionally, while the friction coefficient of the surface property increased. Furthermore, the study showed that W/A 50/50 possesses the most superior tensile property and shearing property, which could attain the optimum blending ratio. Similar results in hand value were derived in all the samples. After washing, however, the increase in acrylic's blending rate caused a proportional decrease in KOSHI and an increase in FUKURAMI. In addition, W/A 50/50 gained the biggest NUMERI value, again corresponding to the optimum blending ratio. Similar results in total hand value were derived in all the samples before washing. After washing, though, all the total hand values decreased, and, as the wool fabric's blending rate increased, the total hand values proportionally decreased further.

• 한국정밀공학회지
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• 제24권2호
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• pp.118-126
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• 2007

Most of materials receive forces in use so that the characteristics of materials must be considered in system design to prevent deformation or destruction. Mechanical properties of materials can be expressed as responsible level of material itself under the exterior operation. Main mechanical properties are strength, hardness, ductility and stiffness. Currently, among major measure facilities to measure the mechanical properties, advanced indentation technique has important use in industrial areas due to nondestructive and easy applications for mechanical tensile properties and evaluation of residual stress of materials. This study is to find the optimum experimental condition about residual stress advanced indentation technique for accurate analysis of the welded joint of steel materials through indentation load-depth curve obtained from cruciform specimen experiment. Optimum selection was applied to the welded joint of real steel materials to find out non-equi-biaxial stress state and the results were compared with general residual stress analyzing method fur verification.

• 한국미생물·생명공학회지
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• 제27권4호
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• pp.333-338
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• 1999

This study was aimed to develop a value-added fermented products from rice and apple pomace using Bifidobacterium fermentation. The Bifidobacterium fermentation system of the mixture of rice and apple pomace was developed, and the physicochemical properties of the products were investigated. After 4 different bifidobacteria were compared for their fermentation capability and sensory properties of the fermented product, Bifidobacterium FBD-13 and FBD-22 were selected as appropriate strains for the fermentation of saccharified rice solution(SRS). The optimum inoculation level was 2% and the optimum fermentation time was 42 hrs. When wet apple pomace(WAP) was added to SRS, it contributed to the improvement of sensory properties of the fermented products and the optimum mixing ratio was 40% WAP and 60% SRS in weight. For the fermentation of the mixture of WAP and SRS, Bifidobacterium FBD-27 and FBD-22 were selected as suitable strains.

• 연구논문집
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• 통권29호
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• pp.185-194
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• 1999

The shape and thickness distribution according to the pressure-time curve were carried out using the FEM and experiment. Also, mechanical properties were investigated. The square cup parts have been formed with pressure-time curve generated by result of analysis. The tensile strength and elongation have been investigated according to applied pressure conditions using the tensile test specimen obtained from the superplastic formed cup. We can use to predict the shape of formed part under the applied pressure using the FEM analysis. In the case of optimum pressure condition, the thickness distribution and mechanical properties were improved. From this study, we can find the important of optimum pressure-time condition. We have investigated about the forming of airplane part and fuel tank for motorcycle. If the applied load used in boundary conditions was appropriate, the simulation result coincides with the formed part. However, it is very difficult to define the pressure condition in complicated shape. Thus, it is need to develop the optimum pressure condition for superplastic forming.