• International Journal of Quality Innovation
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• v.2 no.2
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• pp.69-92
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• 2001

The laser-assisted seeding (LAS) process has potential to replace conventional electroless copper plating in Printed Circuit Board (PCB) manufacturing since it combines the steps of laser drilling and plating into one single process. In the LAS process, the single extra LAS step can metallize a microvia. Thus, the process steps can be greatly reduced and the productivity enhanced, but also the high aspect ratio microvias can be metallized. The objectives of this paper are to study the LAS copper thickness within PCB microvias and the thermal reliability of the microvias produced by this process. It was found that results were satisfactory in both the reliability test and also the LAS copper thickness which both comply with IPC standard, the copper thickness produced by the LAS process is sufficient for subsequent electro-plating process. The reliability of the microvias produced by LAS process is acceptable which are free from any voids, corner cracks, and distortion in the plated copper.

• Industrial Engineering and Management Systems
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• v.7 no.2
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• pp.113-125
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• 2008

This paper presents a model for designing cellular manufacturing systems (CMS) by integrating system cost, machine reliability, and preventive maintenance (PM) planning. In a CMS, a part is processed using alternative process routes, each consisting of a sequence of visits to machines. Thus, a level of 'system reliability' is associated with the machines along the process route assigned to a part type. Assuming machine reliabilities to follow the Weibull distribution, the model assigns the machines to cells, and selects, for each part type, a process route which maximizes the overall system reliability and minimizes the total costs of manufacturing operations, machine underutilization, and inter-cell material handling. The model also incorporates a reliability based PM plan and an algorithm to implement the plan. The algorithm determines effective PM intervals for the CMS machines based on a group maintenance policy and thus minimizes the maintenance costs subject to acceptable machine reliability thresholds. The model is a large mixed integer linear program, and is solved using LINGO. The results point out that integrating PM in the CMS design improves the overall system reliability markedly, and reduces the total costs significantly.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.206-210
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• 2007

IEC 62278 presents a process to implement a consistent approach to the management of reliability for railway applications. A reliability program has to be established at the outset of a project in order to manage reliability activities effectively through the life cycle. The first step of the reliability program is to evaluate reliability requirements and targets based on the system specifications. The system specifications are derived from the customer's needs. The way in which the system requirements reflect the customer's needs is strongly dependent on the characteristics of the product. In general the customer of commercial trains presents the system requirements from their needs. However, the relation between the customer and supplier is equivocal for a project to development a prototype train, and the reliability program should be different from that of an usual commercial project. This paper deals with a process to manage reliability activities for the development of a protype train based on the experiences obtained from the development of the Korea High-Speed Train: Hanvit-350.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.2 no.2
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• pp.1-4
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• 1979

In order to cope with the violent environment of surrounding enterprises, development of new products, advance to other industry field, unification or abolition of factories and rationlization of labor are needed. But production process being made quality and using process after shipment are the things that we have to think about, first of all and to practice always. Insurance problem of reliability, that is, the positive quality maintenance that has being presented many debate issues recently, will be studied. The accident of nuclear power-plant in America, in connection with reliability maintenance and human engineering, will be analyzed. But as its accident details is not announced, in this study, it is a sort of method of methodology to be studied this paper rather than studying the fact of the accident. Therefore this study will be done as follows, For reliability study. 1. Investigation of problems. 2. Quality maintenance activity and reliability maintenance activity 3. Reliability acquisition in production process, 4. Reliability maintenance after shipment. 5. Conclusion. In addition to stating above, it is sure that liberalization of trade, interchange between nations and strengthening of international competition ability, etc. need high quality. But possibility that quality maintenance or reliability aquisition needs understanding and cooperation of consumer, will be stated.

• Journal of the Korean Society of Systems Engineering
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• v.3 no.2
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• pp.33-38
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• 2007

This paper describes a basic process of reliability analysis in shipped guided weapons. The OMS/MP provides originating data for RAM analysis. However, The process of reliability analysis is often done with an insufficient understanding of OMS/MP. This work proposed the improved reliability analysis process with Relax. It is shown that the process is applicable to shipped guided weapons.

• Journal of Information Technology Applications and Management
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• v.23 no.4
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• pp.117-125
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• 2016

Software reliability in the software development process is an important issue. In infinite failure non-homogeneous Poisson process software reliability models, the failure occurrence rates per fault. can be presented constant, monotonic increasing or monotonic decreasing pattern. In this paper, the reliability software cost model considering decreasing intensity function was studied in the software product testing process. The decreasing intensity function that can be widely used in the field of reliability using power law process, log-linear processes and Musal-Okumoto process were studied and the parameter estimation method was used for maximum likelihood estimation. In this paper, from the software model analysis, we was compared by applying a software failure interval failure data considering the decreasing intensity function The decreasing intensity function model is also efficient in terms of reliability in the arena of the conservative model can be used as an alternating model can be established. From this paper, the software developers have to consider life distribution by preceding information of the software to classify failure modes which can be gifted to support.

• Journal of Korean Society for Quality Management
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• v.43 no.4
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• pp.499-510
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• 2015

Purpose: This paper treats the improvement of the quality and reliability of military weapon systems based on the maintenance data. Methods: The proposed method of the data integration and refinement are used to obtain the component reliability information and to find the frequently failed components based on the Pareto analysis. Based on the reliability information and the number of failed component frequencies, the target components of quality improvement are determined and improved by multiple methods such as engineering changes, special meetings, additional training and revising maintenance manuals. Results: Based on the proposed process, we find some components which need to be improved in order to enhance the quality and reliability. Conclusion: A process is developed for improving the quality and reliability of weapon systems. This process will be adopted by various weapon systems to enhance the quality and reliability, as well as reduce military spending.

• Journal of Applied Reliability
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• v.13 no.3
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• pp.175-190
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• 2013

This study considers reliability growth management as the excellent method for construction equipment development with the effect on decreasing COPQ(Cost of Poor Quality Cost) of new products. MIL-HDBK-189A(1981) and RADC-TR-84-20(1984) standards provide a general concept of reliability growth management including to reliability growth test, models and FRACAS(Failure Reporting and Corrective Action System). There is no study how to apply reliability growth management to construction equipment(or machine) development. This paper propose the method to apply it to construction equipment development process from the reliability target setting for developing products to launching them at market. It is expecially showing how to set target reliability for new developing equipment and the development risk to reach the reliability target in detail.

• Journal of the Korean Institute of Gas
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• v.17 no.1
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• pp.49-55
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• 2013

Large scale systems, the facilities for the production of power, gas and chemical, have the complex structures. Most systems require the high reliability for the improvement of process efficiency, but it is difficult to analyze the reliability of processes with complex structures. In this study, we investigated reliability path of chemical process with k-out-of-n system by reliability block diagram(RBD) and calculated the reliability of process through the failure enumeration method of reliability path. This method should help in analyzing the reliability of k-out-of-n system.

• Journal of the Korean Society of Systems Engineering
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• v.17 no.1
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• pp.1-10
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• 2021

In this paper we proposed the alternative analysis of reliability design using redundancy technique. First, we presented the process for establishing the reliability design alternative analysis process considering the active redundancy and the standby redundancy. and then, the case analysis of A driving equipment was performed in accordance with the reliability design alternative analysis process presented. In case the series reliability design result is not met with the reliability target value. so, the target item for redundancy design of A driving equipment were selected as items with a severity of two or higher. The redundancy design applied with active and standby redundancy techniques were analyzed using BlockSim software. As a result, it was analyzed that reliability design to active redundancy with one of two elements required for A driving equipment is the most efficient compared to the target value of reliability. The results of this study can be usefully used before the reliability design is performed.