• Journal of Korea Society of Industrial Information Systems
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• v.11 no.2
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• pp.40-47
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• 2006

The learning control develops controllers that learn to improve their performance at executing a given task, based on experience performing this specific task. In a previous work the authors presented an iterative precision of linear decentralized learning control based on p-integrated teaming method for the vertical dynamic multiple systems. This paper develops an indirect decentralized learning control based on adaptive control method. The original motivation of the loaming control field was learning in robots doing repetitive tasks such as on a]1 assembly line. This paper starts with decentralized discrete time systems, and progresses to the robot application, modeling the robot as a time varying linear system in the neighborhood of the nominal trajectory, and using the usual robot controllers that are decentralized, treating each link as if it is independent of any coupling with other links. Error wave propagation method will show up in the numerical simulation for five-bar linkage as a vertical dynamic robot. The methods of learning system are shown up for the iterative precision of each link at each time step in repetition domain. Those can be helped to apply to the vertical multiple dynamic systems for precision quality assurance in the industrial robots and medical equipments.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.16 no.28
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• pp.181-186
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• 1993

The objective of this paper is to present a method for synthetic performance and quality evaluation of dial up network modem in users place. In the past, universally recognized criteria have not been available to model switched network modem performance. Reasonable assurance of modem performance on the public switched telephone network by standardized test channel which is suggested by ELA(Electronic Industries Association). These tests of modem from a variety manufacturers more reflective of actual performance on the network.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.15 no.25
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• pp.75-82
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• 1992

Standard acceptance sampling plans models the production pricess as a sequence of independent identically distributed Beruoulli random variables. However, the quality of items sampled sequentially from an ongoing production process of ten exhibits statistical dependency that is not accounted for in standard acceptance sampling plans. In this paper, a dependent production process is modelled as an ARMA process and as a two-state Markov chain. A simulation study of each is performed. A comparison of the probability of acceptance is done for the simulation method and for the approximation method.

• Journal of Welding and Joining
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• v.25 no.6
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• pp.84-95
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• 2007

The International System for Education and Qualification of Welding Personnel has been implemented based on the harmonized European System for education and qualification of welding personnel. This paper gives an overview of the International System focusing on the training guidelines and the quality assurance system developed. Systems for harmonization of Certification of Welding Personnel and for supporting companies using welding to implement ISO 3834 have been developed by EWF and are presently being transferred to IIW in line with the EWF/IIW agreement established in 2000.

• Journal of Korean Society for Quality Management
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• v.46 no.3
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• pp.465-482
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• 2018

Purpose: This article aims 1) to propose improvement directions of the certification by recognizing the quality management practices based on the analysis of the audit results of the military contractors and 2) to suggest some ideas on quality audit planning preparation to help the government quality assurance representatives. Methods: Based on the nonconformity report of the defense quality management system (DQMS) requirements, frequently occurring requirement components are found and summarized. Three hypothesis testings are executed to check whether the maturity levels of the quality management systems are influenced by the company size, weapon tye, and company type, regarding the nonconformity frequency as dependent variable. Results: Nonconformity occurs most frequently in the order of product realization, measurement analysis and improvement, management responsibility, resource management, and quality management system. Nonconformity reduces when the company size increases, for the guided weapons, and in the defense companies. Conclusion: Since small-sized companies are inferior to larger companies with respect to the DQMS maturity level, more support should be provided to these small-sized companies which produce military supplies.

• Journal of the Korean Society for Precision Engineering
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• v.13 no.12
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• pp.63-69
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• 1996

As the significance of quality in the sense of customer satisfaction is growing, the management of quality becomes one of the main interests in the manufacturing systems research. This paper presents the concept of quality-driven CIM(Computer Integrated Manufacturing) system which is composed of a business process domain and a quality domain. In the business process domain, business functions are integrated by conventional design and manufacturing databases on the one hand, and an integrated quality system is interlinked to them via several quality modules on the other hand. Quality information model connects the business process domain with the quality domain where various types of quality data are stored in the form of quality database. This framework helps a manufacturing enterprise to implement the quality-driven CIM system to achieve its final objective "customer satisfaction".ion".uot;.

• Journal of Korean Institute of Industrial Engineers
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• v.33 no.2
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• pp.191-200
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• 2007

We propose the QoS (Quality of Service) assurance model for AMR (Adaptive MultiRate) voice users considering the capacity and service quality jointly in downlink WCDMA system. For this purpose, we introduce a new system performance measure and the number-based AMR mode allocation scheme. The proposed number-based AMR mode allocation can be operated only with the information of total number of ongoing users. Therefore, it can be more simply implemented than the existing power-based allocation. The proposed system performance measure considers the stochastic variations of AMR modes of ongoing users and can be analytically obtained using CTMC (Continuous Time Markov Chain) modeling. In order to validate the proposed analytical model, a discrete event-based simulation model is also developed. The performance measure obtained from the analytical model is in agreement with the simulation results and is expected to be useful for parameter optimization.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.2
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• pp.335-342
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• 2020

ESS(Environmental Stress Screening) is an important production process to remove 'latent defects' introduced in the production of products. Recently, ESS is included in QAR(Quality Assurance Report) as an essential quality assurance requirement for products in the defense business. However, depending on the author of the QAR or the classification of the weapon system, it is often identified that the content and form are different or important elements are omitted. Therefore, this paper proposes a MIL-HDBK-344A based quantitative ESS requirement standard to secure the consistency and completeness of QAR. and to make easier to calculate PE(Precipitation Efficiency), which is an indicator for identifying the latent defects elimination effect.

• Journal of the Korea Institute of Building Construction
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• v.11 no.3
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• pp.292-300
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• 2011

The construction industry in Korea has seen significant improvements in quality management techniques, driven by the dramatic development of new technology through Manhattanization and enlargements, but compared with technical development, the level of building quality improvement is still lagging behind. In the meantime, as the interest in construction quality soars due to changes in user consciousness, the level of quality that is being demanded is rising. The government has reinforced quality systems by implementing responsible supervision requirements and granting overseas companies permission to enter the supervision business in Korea, and private sector companies also are attempting quality improvement through quality assurance approaches like the preliminary qualification screening system and ISO 9000 series. But currently, building constructions are done only according to the construction specifications of project owners, whose design, materials and construction methods are already decided, and do not leave any necessity or opportunity for technical developments for the quality improvement of contractors. Therefore, in this study, a work process and system improvement plan for payment regulations is proposed, with which contractors can secure quality voluntarily in the building construction phase.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.35 no.3
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• pp.148-154
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• 2012

The purpose of this study is to develop measurement items for quality cost in service industries. Quality cost is necessary in order to evaluate quality management activities. It is clear that the quality cost in service industry is different from manufacturing industry. Generally, in service industries, quality cost is very difficult to assess because it has a unique characteristics. This paper proposes an effective method for measuring quality cost in service industries. Based on the PAF (Prevention, Appraisal, Failure) cost model, we utilizes the concept of five demensions in SERVQUAL which are tangibles, reliability, responsiveness, assurance, empathy. This paper also presents to a standard model for quality cost measurement in service industries.