Earticle

In plants, glycoproteins have been implicated in a wide variety of cellular processes including production of cell walls, pollination, pathogen defence and cell-to-cell communication. In addition, they have attracted considerable interest from the medical field as the main cause of food and pollen allergies. N-glycosylation is a complex process that encompasses the biosynthesis and modification of sugar moieties in the endoplasmic reticulum (ER) and Golgi. The core oligosaccharide Glc3Man9GlcNAc2 is assembled by a series of membrane-bound glycosyltransferases as the lipid carrier dolichylpyrophosphate-linked glycan in the endoplasmic reticulum (ER). The first step of this assembly pathway on the ER luminal side is mediated by ALG3 (asparagine-linked glycosylation 3), which is a highly conserved reaction among eukaryotic cells. In Arabidopsis ALG3 mutant (alg3), an immature lipid-linked oligosaccharide structure, M5ER, was synthesized and efficiently processed into complex-type glycans. Although no high-mannose-type glycoproteins are detected in alg3 plants, these plants do not show a growth phenotype under normal growth conditions. However, the glycosylation abnormalities result in activation of marker genes diagnostic of the unfolded protein response and alg3 mutant showed a stress sensitive phenotype. These results indicate that ALG3 is a critical factor for correct N-glycosylation of proteins and is involved in the ER stress response.

This paper deals with the performance evaluation of determining production size specifications. A customer who does not find the size specification he or she wants may purchase rather a larger or smaller one, but the purchasing desire decreases as the difference between the required and the prepared sizes increases. Introducing a generalized quality loss function which reflects how much the purchasing desire changes according to the difference, Park and Kim(1992) formulated a mathematical model for determining the size specifications so as to minimize the expected loss. Afterward the model has been applied to the determination of sizing system for mail order clothing and brassiere (Lee and Choi, 1996; Chun, et.al., 1996). The performance of the size determination method proposed by Park and Kim is evaluated in this paper. Usually the intervals between two successive size specifications are determined to be equal, but the size determination method compares favorably with the equidistance case, and more favorably if the population distribution is more skewed.

Quality requirements of manufactured products or parts are given in the form of specification limits on the quality characteristics of individual units. If a product is to meet the customer's fitness for use criteria, it should be produced by a process which is stable or repeatable. In other words, it must be capable of operating with little variability around the target value or nominal value of the product's quality characteristic. In order to maintain and improve product quality, we need to apply statistical process control techniques such as histogram, check sheet, Pareto chart, cause and effect diagram, or control charts. Among those techniques, the most important one is control charting. The cumulative sum (CUSUM) control charts have been used in statistical process control (SPC) in industries for monitoring process shifts and supporting online measurement. The objective of this research is to apply Taguchi's quality loss function concept to cost based CUSUM control chart design. In this study, a modified quality loss function was developed to reflect quality loss situation where general quadratic loss curve is not appropriate. This research also provided a methodology for the design of CUSUM charts using Taguchi quality loss function concept based on the minimum cost per hour criterion. The new model differs from previous models in that the model assumes that quality loss is incurred even in the incontrol period. This model was compared with other cost based CUSUM models by Wu and Goel, According to numerical sensitivity analysis, the proposed model results in longer average run length in in-control period compared to the other two models.

Process capability indices are widely used in industries and quality assurance system. In past years, process capability analysis have been used to characterize process performance on the basis of univariate quality characteristics. However, in actual manufacturing industrial, statistical process control (SPC) often entails characterizing or assessing processes or products based on more than one engineering specification or quality characteristic. Therefore, the analysis have to be required a multivariate statistical technique. This paper introduces to multivariate capability indices and then selects a multivariate process capability index incorporated both the process variation and the process deviation from target among these indices under the multivariate normal distribution. We propose a new multivariate capability index $MC_{pm}^+$ using quality loss function instead of the process variation and this index is compared with the proposed indices when quality characteristics are independent and dependent of each other.

If the specifications of product. in general. art determined too wide. the precision of product becomes diminished. Otherwise it costs dearly to keep the precision. Therefore, It is realistic to consider various factors in determining specification of qualify characteristics TAGUCH Idefines quality of an object as "Quality is the loss that a product causes to society after being shipped. other than any losses caused by its intrinsic function". Particularly, to improve the performances of product TAGUCHI focuses his attention on the product design and process design which enable the functional characteristics of product to he robust to noises. In this paper, by the TAGUCHI's loss function, the characteristics which affect the variation of a product performance are classified into the scrappable characteristics and the reworkable characteristics when the target values of functional characteristics have been determined. And we will determine the tolerance of each characteristic which minimize the quality cost by the cost function which considers the economic factors and probability features of each characteristic.cteristic.

기업이 품질 지향적이어야 한다는 점에 대해서는 모두가 동의하는 사실이며, 품질개선을 추구하는 것은 모든 기업들에게 가장 핵심적인 이슈중의 하나가 되고 있다. 그러나 기존의 품질연구 및 실행들을 살펴보면, 사회적 책임 등에 대한 문제제기에도 불구하고, 대부분 경영/관리적인 측면에만 집중되어 왔던 것이 사실이다. 따라서 품질경영에 있어 사회적 측면을 감안할 필요성이 생겨나게 되었고, 본 연구에서는 사회적 측면과 경영/관리적 측면을 통합적으로 고려하여 품질에 대한 폭넓은 해석을 시도하고, 이를 토대로 품질지향성이라는 새로운 개념을 도출하였다.