• Analytical Science and Technology
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• v.32 no.2
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• pp.48-55
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• 2019

The simple and effective analytical method for the quality control of a novel scalp tonic formulation has been developed and optimized in terms of HPLC conditions and sample preparation method, meanwhile, the optimization of preparation condition was using response surface methodology (RSM) based on central composite design (CCD). Oleanolic acid was selected as marker compound because of its bioactivities for alopecia therapy. The developed analytical method and extraction condition were successfully qualified. Coefficient of determination ($r^2$) for the calibration was 0.9997 with a line passing through the origin point in the range of 0.1-100 mg/mL. The limit of detection (LOD) and the limit of quantitation (LOQ) were 17.5 ng/mL and 55.0 ng/mL, respectively. The intra-day and inter-day precision of the method were 0.5-1.4 % and 0.7-1.8 % in relative standard deviation, respectively, while those accuracy were 99.5-100.9 % and 100.0-102.2 %, respectively. The repeatability of oleanolic acid in samples ranged of 0.3-1.9 % based on peak area and 0.3-0.7 % for retention time. Recoveries from samples were 95.0-99.4 % with lower than 1.8 % in relative standard deviation. Overall, the developed analytical method will be used for quality control of this commercial scalp tonic products successfully.

• Journal of Korean Society for Quality Management
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• v.20 no.1
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• pp.68-79
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• 1992

The economic order quantity(EOQ) is a robust quantity, and it is largely insensitive to reasonable errors in the estimation of most of its parameters. Optimal EOQ and reorder point which are not sensitive to the estimates of the various cost model parameters for Kim and Park's model are determined. This of Taguchi's parameter design which finds a robust EOQ and reorder point using reasonable cost structure on the assumption of normally distributed quality characteristic. A numerical example is also presented to illustrate the proposed procedure and computer aided numerical experiments for selected values of backordered fractions and standard deviations are performed.

• Industrial Engineering and Management Systems
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• v.7 no.2
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• pp.93-100
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• 2008

Quality function deployment (QFD) provides a specific approach for ensuring quality throughout each stage of the product development and production process. Since the focus of QFD is placed on the early stage of product development, the uncertainty in the input information of QFD is inevitable. If the uncertainty is neglected, the QFD analysis results are likely to be misleading. It is necessary to equip practitioners with a new QFD methodology that can model, analyze, and dampen the effects of the uncertainty and variability in a systematic manner. Robust QFD is an extended version of QFD methodology, which is robust to the uncertainty of the input information and the resulting variability of the QFD output. This paper discusses recent research issues in Robust QFD. The major issues are related with the determination of overall priority, robustness evaluation, robust prioritization, and web-based Robust QFD optimizer. Our recent research results on the issues are presented, and some of future research topics are suggested.

• 한국해양학회지
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• v.6 no.2
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• pp.78-84
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• 1971

A year-long survey of bacteriological water quality for Lake Eui-am in Kang- won Province, Korea, was conducted from June 1970 to May 1971. the purpose of this investigation was: 1) to determinate the seasonal prevalence of fecal pllution bacteria, such as coliforms, fecal coliforms and enterococci, in Lake Eui-am; 2) to correlate these findings with associated microbiological parameters; and 3) to interpret these results with respect to water quality and environmental health. The membrane filter techniques were used, for the determination of these bacteria.Densities of total coliforms, fecal coliforms and enterococci exhibited seasonal variations, the numers of these fecal pollution bacteria being high in summer and fall months in close possitive relation to the amount of rainfall, and being low winter and spring months. On the whole, the level of fecal pollution bacteria in Lake Eui-am is yet quite low There were not any evident correlation among the density of these pollution bacteria. The ratio of fecal coliforms to enterococci of the lake water varied from 0.01 to 4.25 with average of 1.47.

• Journal of Korean Society for Quality Management
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• v.28 no.2
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• pp.1-16
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• 2000

This paper considers the problem of determining the optimal process mean and screening specification limits of a surrogate variable associated with product quality under two-stage screening procedure. In two-stage screening, the surrogate variable is inspected first to decide whether an item should be accepted, rejected or additional observations should be taken. If additional observations are required, the performance variable of interest is then observed to classify the undecided items. Assuming that the performance variable and the surrogate variable are jointly normally distributed, the optimal process mean and the screening limits are obtained by maximizing the expected profit which includes selling price, production, reprocessing, inspection and penalty costs. A numerical example is presented and numerical studies are performed to compare the proposed two-stage screening procedure with single-stage screening procedures.

• Journal of Institute of Control, Robotics and Systems
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• v.3 no.6
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• pp.652-658
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• 1997

Coagulant feeding control is very important in the water treatment process. Coagulant feeding is related to the raw water quality such as turbidity, alkalinity, water temperature, pH and so on. However, since the process of chemical reaction has not been clarified so far, coagulant dosing rate has been decided by jar-test. In order to overcome the difficulty mentioned above, Fuzzy Neural Network to fuse fuzzy logic and neural network was proposed, and the scheme was applied to the automatic determination of coagulant dosing rate. This algorithm can automatically identify the if-then rules, tune the membership functions by utilizing expert's experimental data. The proposed scheme is evaluated by computer simulation and interfaced with coagulant feeder operated by magnetic flowmeter, control valve and PLC. It is shown that coagulant feeding according to real time sensing of water quality is very effective.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1203-1204
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• 2007

In the methods for securing software quality and safety, two approaches - product centered approach and process centered approach - can be suggested. SPICE is a standard for the process improvement and the capability determination, which is planned for securing software quality and safety by the process centered approach. In this paper, general SPICE model, which is presented in ISO/IEC 15504 and Automotive SPICE model for automobile industry are analyzed. For securing railway software quality and safety, appropriate scheme to apply Automotive SPICE to railway software is proposed.

• Journal of Korean Society for Quality Management
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• v.26 no.1
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• pp.61-73
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• 1998

The quality control literature contains a substantial number of articles concerned with how to optimally choose control limits in order to minimize production cost. The purpose of the this study is to determine the economic setting for the process mean of an industrial process. In this study it is assumed that the lower control limit is set by government regulations and the u, pp.r limit and process mean are chosen based on economic considerations. Much research has been conducted on this problem under the condition of the fixed rpm(rate per minute). However a variance can be increased in proportion to the level of rpm and the increase of the variance can change the optimal process mean. Therefore, it is desirable to determine both the process mean and the level of rpm simultaneously. In this paper, a mathematical model is presented which considers the u, pp.r limit and the rpm as variables.

• Food Science and Preservation
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• v.1 no.1
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• pp.29-36
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• 1994

This study was carried out for the establishment of optic harvest date and storage condition of 'Fuji' apple for CA storage. Apples were picked at 10 day intervals from 17 Sept to 27 Oct.. Apples were analyzed for respiration rata, weight flesh firmness, titratable acidity, soluble solid, total sugar, reducing sugar, surface color and thiault value. In 1990, the optimal harvest season could be judged between 17 Oct. and 27 Oct. from the results of respiration rate rise and change of quality properties. Apples harvested on 27 Oct. wert stored at 2$^{\circ}C$ and 90~95% RH in 1%O2 + 3%CO2, 3%O2 + 3%CO2 and air for 9 months. After 9 months of storage, apples kept in CA storages had beater quality than apples kept in refrigeration storage. Especially, apples kept in 1%O2, + 3%CO2 were fumer and more acid than those kept in 3%O2 + 3%CO2 At the sensory evaluations, apples stored in CA were rated higher quality than apples stared refrigeration.

• Archives of design research
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• v.18 no.1 s.59
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• pp.59-68
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• 2005

In 20th century, that is the times of mass production with mass consumption, a company supplies standard product by the system of mass production line. Therefore, the company, itself, had to introduce its product quality to the customers. It was the buying criterion of consumer against product. In that period, a company utilized its identity in order to give customers product information such as product value, price and quality, etc. However, as digital technology with the wide-spread of informationalization & technical revolution is developed, products have diversification and customers have better incomes. So, buying method tends to thi purchase of self-satisfaction generally. In the buying criterion of consumerbased on personality & sensibility, a company must offer the buying criterion of product which can appeal the special quality & image of product itself to customers, and it must stop appealing the Cl of company under the condition of mass production by product quality and function. This study tried to focus on the method which can create effective brand and its image that are the buying criterion of new product. Also, this study tried to find the effective relation between economical & social paradigm which is the result of social informationalization with intensive knowledge, and buying determination of customer, And, this study tried to present guideline of effective brand image and brand special Quality that is affected to buying determination of customers together. The model of Positive analysis had two types. The first model studied the mutual relation between economical/social change factors and special quality of brand. And, the second model studied the mutual relation between the cause of special quality of brand and formation of brand image through regression analysis. Therefore, the construction of sensitive brand image for forming brand must be requested. The sensitive brand image is highly related to preference of sensibility, and it must be based on mind identity & visual identity. And, mind identity must have creation of value, satisfaction, combination of community, personal preference, etc. Visual identity must have esthetic order, and originality of molding, etc. Namely, brand image must form the accommodation of era change, personality & sensibility satisfaction, the effectiveness of service, etc., in order to create effective brand image.