• 산업공학
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• 제12권1호
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• pp.150-157
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• 1999

Mini-Mill process has been recently in operation at Pohang steel company, which enables more flexible steel coil production on customer demands. The effects of process parameters in Mini-Mill process need to be analyzed not only to make the process stable but also to improve product quality. This work aims to develop a regression model of Mini-Mill process using accumulated product data such that the process parameter effects on product tensile strength may be analyzed. The analysis shows that tensile strength is influenced mainly by the amount of components such as carbon, manganese, silicon, and sulfur. The effect of temperature is shown to be small. It is concluded that control of the components is much more responsible for both meeting the target and reducing the variation of the product tensile strength. Heat treatment is more useful in compensating tensile strength variations due to thickness differences and improving workability and other quality characteristics. More work is necessary for establishing regression expressions of the process that is reliable and accurate enough to dispense with the off-line inspection of the product tensile strength.

• Journal of Pharmaceutical Investigation
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• 제37권6호
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• pp.329-338
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• 2007

The quality assurance issue of drug products is more important than the general product because it is highly related to the human health and life. In this reason, the regulatory guide lines have continuously been intensified all around the world. In order to achieve effective quality assurance and real-time product release (RTPR) of drug products, process analytical technology (PAT), which can analyze and control a manufacturing process, has been proposed from the United States. With the PAT process, we can obtain significant process features of materials, quality characteristics and product capabilities from a raw material to the final product in the real-time procedure. PAT can also be utilized to process validation using information system that can analyze the risk of drug products through out an entire product life-cycle. In this paper, we first offered a new concept for the off-line process design methods to prepare the improved quality assurance restrictions and a real-time control method by establishing an information system. We also introduced an automatic inspection system by obtaining surrogate variables based on drug product formulations. Finally, we proposed an advanced PAT concept using validation and feedback principles through out the entire life-cycle of drug product manufacturing processes.

• 품질경영학회지
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• 제25권2호
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• pp.140-153
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• 1997

As product quality is maily determined in the product design and process design step, systematic design should be performed through parameter design and tolerance design. Therefore, we introduced analysis of variance and regression analysis as a statistical method which determine optimal levels of affective design factors to product characteristics, then we compared that process and result. In analysis of variance, variation of quality characteristics arises from noise factors, so the optimal levels of design factors are selected to minimize the effect of noise factors. In regression analysis, variation of quality characteristics aries from variation of each own design factors. As a method to reduce variation of these quality characteristics, sensitivity analysis was performed about each design factors. Through this sensitivity analysis, we represented process to calculate the interaction term of the factors.

• 품질경영학회지
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• 제21권2호
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• pp.27-34
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• 1993

Quality Assurance Method of Defense Logistics Agency, U. S. A., was changed from Contract Quality Assurance Program to In-Plant Quality Evaluation in May, 1990. IQUE focuses on working with contractor in spirit of team work to measure and continuously improve processes and resulting product quality. The goals are to achieve customer satisfaction, improved product quality, and a reduction in the costs of items and ownership. It is suggested to adopt and apply the IQUE method to the effective accomplishment of Korean aircraft projects.

• 한국응용과학기술학회지
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• 제15권4호
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• pp.27-34
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• 1998

The natural body foam product which palm oil is added to this product, differs from products for clothes and Kitchen detergent, industrial and domestic detergent, and It has a various characteristics as a soft detergent for bath and hair product. Up to now, vidal sassoon product which imports form overseas and sells in our country, increases every year in consumption quantity. The development of this product tested to consider the quality of product in the effect of import transfer. First of all, the experiment of this product tested the fundamental items of pH, foam formation force, the moisture effect of product, the biodegradation degree of product. In case of palm oil, when it was added to this product in 0.25wt%, we could get experiment results that pH appeared in 6.2, foam formation force in product 1wt% solution appeared in 104ml per 30sec, the skin moisture effect of product appeared in incleasing from 82 a.u to 90 a.u within one hour since we have used the product, the biodegradation degree of surfactant appeared in 96.7%. According to the experiment result of product, we could know the fact that it has a high quality in comparison with other products.

• 한국의류학회지
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• 제32권10호
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• pp.1509-1521
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• 2008

The subjects of this study were middle-aged women in their 40s$\sim$50s and older women aged 60 and over who were living in Seoul and Kyonggi-do, Korea. Through studying the participants' responses to the questions regarding the attributes of apparel quality in terms of the levels of satisfaction and importance, the target consumers' demand has been studied. And, they are applied to a QFD Matrix, to find out the relationship between the attributes of product quality and the guidelines of clothing design. For this study, apparel product quality is composed of five parameters: practicality, aesthetics, brand image, ease of care and fit. For the parameters of apparel product quality, the result of this study show that product improvements are needed in fit, aesthetics and practicality(in order of importance). The level of satisfaction(how satisfied consumer feels) was marked higher in brand image than that of importance(how important it is). To review demands for the apparel product attributes of formal suits for middle-aged and older women, the priority of these attributes through QFD Matrix that shows the relationship between the attributes and dress elements emphasized by designers has been examined. Material was the most important design element in designing formal suits. The shape of the pants was the second because the harmony between the jacket and the pants is important in formal suits. These were followed by trim and color tone of the jacket.

• 품질경영학회지
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• 제34권4호
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• pp.93-101
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• 2006

Robust parameter design is an off-line production technique for reducing variation and improving the quality of products and processes by using product arrays. However, the use of the product arrays usually requires a large number of runs. To overcome the drawback of the product array, the combined array can be used. Also optimizing multiple responses is increasingly important in industry. Using simultaneous optimization measures, we can deal with the multiple response case. In this paper we compare the simultaneous optimization using the Taguchi's product array with using the combined array. And models possible to set on combined arrays are also investigated and compared with the cases of product arrays.

• 품질경영학회지
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• 제43권4호
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• pp.589-606
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• 2015

Purpose: In developing new products, reducing performance variation is important for competitiveness factors such as quality, cost, and delivery. This paper aims at evaluating three performance variations; measurement, performance evaluation, and manufacturing variations, and then improving product and process design, focused on paper helicopter making case study. Methods: For measurement system analysis, gage R&R (repeatability and reproducibility), linearity, stability are evaluated. Since gage R&R are not satisfactory, the measurement system is improved by adopting voice memos application of iPhone and providing standard measurement procedure. To evaluate performance variation, product deterioration and environment factor (wind speed) is considered. Since the existing design is sensitive to these noise factors, a new product design is developed, which is proven to be robust to the noise factors. Finally, manufacturing variations are evaluated with five factors which can cause variation in flight time. To reduce the impact of three significant factors, three improvement methods are applied. Results: Three performance variations are evaluated and robust paper helicopter design is presented. Conclusion: To reduce measurement and process variations, improved measurement method and paper helicopter making procedure are proposed. A new product design is also presented which is robust to deterioration and environmental variation. This paper is expected to benefit students and practitioners who want to have hands-on knowledge on new product quality improvement.

• Journal of Information Technology Applications and Management
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• 제30권2호
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• pp.1-18
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• 2023

Recently, as technology development has accelerated and product life cycles have been shortened, it is necessary to derive key product features from customers in the R&D planning and evaluation stage. More companies want differentiated competitiveness by providing consumer-tailored products based on big data and artificial intelligence technology. To achieve this, the need to correctly grasp the required quality, which is a requirement of consumers, is increasing. However, the existing methods are centered on suppliers or domain experts, so there is a gap from the actual perspective of consumers. In other words, product attributes were defined by suppliers or field experts, but this may not consider consumers' actual perspective. Accordingly, the demand for deriving the product's main attributes through reviews containing consumers' perspectives has recently increased. Therefore, we propose a review data analysis-based required quality methodology containing customer requirements. Specifically, a pre-training language model with a good understanding of Korean reviews was established, consumer intent was correctly identified, and key contents were extracted from the review through a combination of KeyBERT and topic modeling to derive the required quality for each product. RevBERT, a Korean review domain-specific pre-training language model, was established through further pre-training. By comparing the existing pre-training language model KcBERT, we confirmed that RevBERT had a deeper understanding of customer reviews. In addition, all processes other than that of selecting the required quality were linked to the automation process, resulting in the automation of deriving the required quality based on data.

• 품질경영학회지
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• 제43권1호
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• pp.57-66
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• 2015

Purpose: The purpose of this study is to apply the constrained Bayesian estimation methodology for product quality control process and prove the effectiveness of the product management by comparing with the well-known Bayes estimator through data performance result. Methods: The Bayes and constrained Bayes estimators were produced based on the theoretical background and for confirming the effectiveness of suggested application, the deviation index was defined and calculated for the comparison. Results: The statistical analysis result shows that applying the suggested estimation methodology, that is, constrained Bayes estimator improves the effectiveness of the index with regard to reduce the error by matching the first two empirical moments. Conclusion: Considering the advanced Bayesian approaches such as constrained Bayes estimation for the product quality control process, the newly defined deviation index reduces the error for estimating the parameter histogram which is reflected both location and deviation parameters and furthermore various Bayesian perspective approaches seems to be meaningful for managing the product quality control process.