PL시대의 제품안전과 신뢰성을 확보하기 위한 각종 활동 체계와 기법들 및 그 관련성을 알아본다 제품의 신뢰도, 가용도, 안전성, 그리고 보전성을 종합적으로 다루는 통합신뢰성 (dependability) 에 관한 예측 및 분석 기법들과 각 기법의 특징, 적용에 대해 소개하고, 이들 기법을 효과적으로 연계, 활용할 수 있는 안전/신뢰성/품질보증 통합경영시스템에 대해 고찰한다.
시스템이 제공하는 서비스의 질, 정착성 및 연속성과 관련된 정서적 요소 신뢰도, 가용도, 보전도, 안전도를 종합적으로 관리하는 Dependability Management를 다루고 있는 국제표준 IEC 60300 Dependability Management의 Part 3-5(IEC 60300-3-5): 신뢰성 시험조건 및 통계적 검정 원칙의 적용지침을 소개하였다. 표준의 적용범위 및 용어정의, 일반적인 고려사항, 신뢰성시험의 종류와 적용표준, 신뢰성 시험조건, 데이터 수집과 고장분류방법을 요약하였다.
In this paper, the QFD(quality function deployment) technique is used to acquire the quality requirements of package software which is sold in a commercial software shop. To select the principal quality characteristics of package software, an user survey was conducted for a quality model developed based on the international standards and the previous research. The software user is divided into three groups:the general user, the expert, and the developer. The method of QFD is applied to choose the software quality attributes which have strong correlation with the selected quality characteristics.
This paper studies the structure and reliability of homogeneous s-coherent multistate system. We describe efficiency of inclusion-exclusion algorithm and pivotal decomposition algorithm for reliability calculation of 2-states system which developed in (Lee 1999) [10]. We extend our method, applied in [10], to the case when components of the system are given multi-states. As an application, the high pressure injection system of a pressurized water reactor is modeled as a multistate system composed of homogeneous s-coherent multistate subsystems. And Several examples are illustrated.
The objective of this work is to develop the capability to analyze accurately the mixed-mode propagation of a crack in composite structures with elastic orthotropic material stiffness properties and anisotropic material strength characteristics. We employ the normal stress ratio theory to predict the direction of crack extension. It is shown that the angle of crack extension can be altered by the use of second order term in the series expansion is important for the accurate determination of crack growth direction.
Many production management systems for increasing productivity, minimizing inventory, keeping due dates and maximizing use of resources have been proposed, and GT, MRP and JIT are frequently used among these systems. The three systems have merits and demerits through comparing with each other. Because each system has mutual dependence, a hybrid production system is necessary for using their merits maximally. In this study, a hybrid production system is designed by combining GT, MRP and JIT, which is suitable in the domestic production system.
This paper analyses the tool switching problem in the dynamic environment, where parts to be processed on a flexible machine arrive randomly. As the total number of tools required to Process a set of parts on the machine is generally larger than the available magazine storage capacity, tool switches between parts are usually necessary. We assume that tool switching must be made just before the processing of the parts. Since the time required for tool switches can be significant relative to processing time and cause the processing of parts to be delayed, it is desirable to minimize the number of tool switches. Therefore, we present one heuristic algorithm to minimize the total number of tool switches and the t)reposed heuristic is compared with the KTNS (Keep Tool Needed Soonest) policy on randomly generated problems.
This paper addresses the problem of placing tools in a tool magazine with random-select capability on a flexible machine. The tool placement problem could be a significant portion of the total processing time. It is assumed that the total number of tools required to process a set of parts exceeds the available magazine capacity, and so tool switches may occur between two adjacent parts in a given part sequence. Two heuristics are presented so as to minimize the total travel distance of the tool magazine before the completion of all parts.
In today's business transactions, it is more and more common to see that the buyers are allowed some grace period before they settle the account with the supplier. In this regard, we analyze the problem of determining the buyer's EOQ when the supplier allows day-terms credit. For the analysis, it is assumed that the buyer's demand rate is a function of the on -hand inventory level and the relevant mathematical model is developed.
A study to analyze and solve problems of multi wire installation duct experiment has presented in this paper We have taken Taguchi's parameter design approach, specifically orthogonal array, and determined the optimal levels of the selected variables through analysis of the experimental results using S/N ratio.
In the last year, the number of registered vehicles in Korea surpassed the 12 million mark, and increase in number continuously Nowdays, this tendency has raised some problems inevitably in the view of expansion of ELV(end of life vehicle) and earth environment pollution resulted from it. For the proper scope with this environment pollution, recycling of parts and materials, minimization of wastes are desirable. And application of disassembly technology is required for it necessarily. Therefore it is essential to study systematically about disassembly technology of ELV with high efficiency for improvement recycling ratio and diminution shredder dust amount also in Korea.
We consider some alternative management models(IEC300, NASA AHB 5300.1, IEC1508) based on dependability, especially reliability and safety, including resources on world- wide leading standard- bodies and informations.
The purpose of this study is to develop an insurance system for product quality liability(PQL) by reviewing some legal issues concerning the product liability It is concluded that the purpose and the function of PQL insurance have to be considered with robust experience data for the life of product, quality system of the company, size of company, the number and amount of products produced by a company and the type of company etc. And this article reviews some problems of policy including the possibility of anti-selection and reverse selection.
Subsequently in Korea product liability has been introduced. The position of consumers for defective products have been disadvantageous. Defective products should be broght under the law. Then, while consumers would be largely protected, a producer would take the heavy responsibility by law, Therefore, a producer would not be able to take countermeasures for product liability. Object of this paper to investigate and analyze the actual state of management for product liability in advanced countries, and to join it with our quality management system.
Nowadays the most important thing is not to gather new membership but to manage existing membership with useful information in electronic commerce system. To satisfy various customers, it is vital to understand and analyze customer's need. This paper presents the modeling method for efficient marketing system in mobile commerce.