• 한국융합학회논문지
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• 제9권7호
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• pp.223-230
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• 2018

장시간 저장되어 있다가 사용되는 일회성 군수장비 시스템의 경우, 저장 시간이 지남에 따라 저장신뢰도에 변화가 발생하게 된다. 이에 사용시점이 도래하였을 때 제품 사용에 있어 저장신뢰도가 중요한 품질특성으로 작용하게 되며, 기존의 연구들은 저장신뢰도 향상을 위하여 최적의 정기검사주기 산출을 위한 연구에 초점이 맞춰져 있었다. 본 연구에서는 정기검사주기 뿐 아니라 설계신뢰도를 포함한 분석을 통해 융합적인 관점에서 저장신뢰도에 두 인자가 얼마나 영향을 미치는지 분석을 수행하였다. 이를 위해 일회성 시스템의 대표적인 제품인 유도탄에 기존의 Martinez 저장신뢰도 결정모델을 적용하여 각각 설계신뢰도와 정기검사주기가 미치는 정량적인 효과에 대하여 분석을 수행하였다. 분석 결과를 통해, 현 제품의 설계신뢰도 범주 내에서는 설계신뢰도보다는 정기검사주기 관리가 저장신뢰도 향상에 더 중요한 요인이라는 것을 확인해 볼 수 있었다.

• 한국유기농업학회지
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• 제20권2호
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• pp.125-142
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• 2012

The purposes of this study are to analyze the effect of consumption of environment-friendly agricultural products (EFAP) on improvement of family health, and to suggest directions for improvement of family health. A survey was conducted for qualitative analysis regarding relationship between EFAP consumption and family health. The method of his study was employed Cross-tabulation and an Ordinal Logistic Regression Model to derive more significant results in analyzing factors of improvement of family health. The result shows that improvement of health has a significant positive relationship with consumption of EFAP. In addition, those consumers with high reliability and quality contentment are more likely to experience improvement of health. As consumers constantly eat EFAP, they are more likely to experience improvement of health. In order to provide consumer reliability of EFAP, more strict certification management system with sound monitoring and an appropriate penalty for violation should be established.

• 한국철도학회논문집
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• 제11권4호
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• pp.390-397
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• 2008

정량적 RAM(Reliability, Availability, Maintainability)은 철도차량의 품질을 나타내는 중요한 척도중 하나이다. 국내외의 철도차량 구매사양서에서는 정량적 RAM 요구조건이 제시되고 있으며 이에 대한 달성과 입증을 요구하고 있다. 본 연구에서는 철도차량의 정량적 RAM의 목표값을 설정하는 방법을 서비스 신뢰도, 로지스틱 신뢰도, 운영가용도와 성취가용도 또는 고유가용도, 유지보수성 측면에서 제안한다. 그리고 이 설정방법을 실제 철도차량 운영데이터에 적용해 보았다.

• 수산해양교육연구
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• 제25권5호
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• pp.1214-1223
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• 2013

The purpose of this work is to analyze the factors, criteria and importance that shippers in the international logistics industry take into account in choosing third-party logistics, and thereby to propose the directions of the areas and functions that third-party logistics will need to enhance on the basis of Analytic Hierarchy Process (AHP) methodology. To do that, this work collected and analyzed materials about changing environments of logistic industry and previous studies, and especially conducted a questionnaire survey on the factors to choose third-party logistics with the study subjects of shippers in the international logistics industry. To draw attribute factors, this work repeatedly chose and classified candidate factors through Delphi technique on the basis of the data of previous studies. The analysis results are presented as follows: regarding pairwise comparison between logistic cost and logistic service in relation of conflict, logistic service was recognized to be more important than logistic cost; regarding pairwise comparison between corporate capability and logistic cost, logistic cost was recognized to be more important; and regarding comprehensive evaluation, logistic service factors, including accuracy of order handling, service reliability, freight damage and compensation, a degree of fulfillment of promise, quality of transportation, and problem-solving ability, were found to be in high position.

• 품질경영학회지
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• 제48권2호
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• pp.297-307
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• 2020

Purpose: The purpose of this study is to analyze the factors that affect ammunition performance by applying data mining techniques to the Ammunition Stockpile Reliability Program (ASRP) data of the 155mm propelling charge. Methods: The ASRP data from 1999 to 2017 have been utilized. Logistic regression and decision tree analysis were used to investigate the factors that affect performance of ammunition. The performance evaluation of each model was conducted through comparison with an artificial neural networks(ANN) model. Results: The results of this study are as follows; logistic regression and the decision tree analysis showed that major defect rate of visual inspection is the most significant factor. Also, muzzle velocity by base charge and muzzle velocity by increment charge are also among the significant factors affecting the performance of 155mm propelling charge. To validate the logistic regression and decision tree models, their classification accuracies have been compared with the results of an ANN model. The results indicate that the logistic regression and decision tree models show sufficient performance which conforms the validity of the models. Conclusion: The main contribution of this paper is that, to our best knowledge, it is the first attempt at identifying the significant factors of ASPR data by using data mining techniques. The approaches suggested in the paper could also be extended to other types ammunition data.

• 한국신뢰성학회:학술대회논문집
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• 한국신뢰성학회 2001년도 정기학술대회
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• pp.277-278
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• 2001

The successful operation of a product In service depends upon the effective provision of logistic support in order to achieve and maintain the required levels of performance and customer satisfaction. Logistic support encompasses the activities and facilities required to maintain a product (hardware and software) in service. Logistic support covers maintenance, manpower and personnel, training, spares, technical documentation and packaging handling, storage and transportation and support facilities.The cost of logistic support is often a major contributor to the Life Cycle Cost (LCC) of a product and increasingly customers are making purchase decisions based on lifecycle cost rather than initial purchase price alone. Logistic support considerations can therefore have a major impact on product sales by ensuring that the product can be easily maintained at a reasonable cost and that all the necessary facilities have been provided to fully support the product in the field so that it meets the required availability. Quantification of support costs allows the manufacturer to estimate the support cost elements and evaluate possible warranty costs. This reduces risk and allows support costs to be set at competitive rates.Integrated Logistic Support (ILS) is a management method by which all the logistic support services required by a customer can be brought together in a structured way and In harmony with a product. In essence the application of ILS:- causes logistic support considerations to be integrated into product design;- develops logistic support arrangements that are consistently related to the design and to each other;- provides the necessary logistic support at the beginning and during customer use at optimum cost.The method by which ILS achieves much of the above is through the application of Logistic Support Analysis (LSA). This is a series of support analysis tasks that are performed throughout the design process in order to ensure that the product can be supported efficiently In accordance with the requirements of the customer.The successful application of ILS will result in a number of customer and supplier benefits. These should include some or all of the following:- greater product uptime;- fewer product modifications due to supportability deficiencies and hence less supplier rework;- better adherence to production schedules in process plants through reduced maintenance, better support;- lower supplier product costs;- Bower customer support costs;- better visibility of support costs;- reduced product LCC;- a better and more saleable product;- Improved safety;- increased overall customer satisfaction;- increased product purchases;- potential for purchase or upgrade of the product sooner through customer savings on support of current product.ILS should be an integral part of the total management process with an on-going improvement activity using monitoring of achieved performance to tailor existing support and influence future design activities. For many years, ILS was predominantly applied to military procurement, primarily using standards generated by the US Government Department of Defense (DoD). The military standards refer to specialized government infrastructures and are too complex for commercial application. The methods and benefits of ILS, however, have potential for much wider application in commercial and civilian use. The concept of ILS is simple and depends on a structured procedure that assures that logistic aspects are fully considered throughout the design and development phases of a product, in close cooperation with the designers. The ability to effectively support the product is given equal weight to performance and is fully considered in relation to its cost.The application of ILS provides improvements in availability, maintenance support and longterm 3ogistic cost savings. Logistic costs are significant through the life of a system and can often amount to many times the initial purchase cost of the system.This study provides guidance on the minimum activities necessary to Implement effective ILS for a wide range of commercial suppliers. The guide supplements IEC60106-4, Guide on maintainability of equipment Part 4: Section Eight maintenance and maintenance support planning, which emphasizes the maintenance aspects of the support requirements and refers to other existing standards where appropriate. The use of Reliability and Maintainability studies is also mentioned in this study, as R&M is an important interface area to ILS.

• Journal of the Korean Data and Information Science Society
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• 제22권3호
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• pp.597-603
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• 2011

The half logistic distribution has been used intensively in reliability and survival analysis especially when the data is censored. In this paper, we provide prole likelihood estimation of the shape parameter and scale parameter in the generalized half logistic distribution based on progressively Type-II censored data. We also introduce approximate maximum prole likelihood estimates for the scale parameter. As an illustration, we examine the validity of our estimation using real data and simulated data.

• International Journal of Reliability and Applications
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• 제5권1호
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• pp.25-36
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• 2004

Ultrasonic inspection system consist of the examination procedures, equipment, and operators. The reliability of nondestructive testing is influenced by the inspection environment, materials and types of defect. It is very difficult to estimate the reliability of NDT due to the various factors. Piping inspection round robin was conducted to quantify the capability of ultrasonic inspection during in-service. In this study, the models for predicting the ultrasonic NDE reliability by logistic model and linear regression model are discussed. The utility of the NDT reliability assessment is verified by the analysis of the data from round robin test with these models.

• International Commerce and Information Review
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• 제2권1호
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• pp.25-48
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• 2009

With the rapid growth of e-logistics in the global logistics industry, it is important to gain further insight into this growing segment of Chinese logistics industry. The current situation in China consists of many small and medium-sized logistics firms. Furthermore, e-logistics is still relatively undeveloped in the majority of the Chinese logistics companies and presently there are still many problems unresolved. This paper attempted to review the concepts and theoretical background of e-logistics systems from previous studies. After acknowledging the essential issues related to e-logistics systems, a research model based on the theory acceptance model was designed and tested. The key factors to the e-logistics system (reliability, maintainability, software, facility and transportation) were validated through the modeling and testing process. Included in the modelling and testing process are other related factors of e-logistics process, logistics information system and added value as dependent variables in this model. The results of this study confirm that the e-logistics Process is affected by transportation, while maintainability and software factors influence logistics information system. reliability, maintainability, facility and transportation are significant factors associated with added value. This research aimed to provide theoretical and practical contribution to Chinese logistics companies and to give some insights into e-logistics system as a whole. The paper also provided some useful theoretical implication and practical guidelines for the development of e-logistics system in the chinese logistics industry.

• 통상정보연구
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• 제11권2호
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• pp.3-26
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• 2009

With the rapid growth of e-logistics in the global logistics industry, it is important to gain further insight into this growing segment of Chinese logistics industry. The current situation in China consists of many small and medium-sized logistics firms. Furthermore, e-logistics is still relatively undeveloped in the majority of the Chinese logistics companies and presently there are still many problems unresolved. This paper attempted to review the concepts and theoretical background of e-logistics systems from previous studies. After acknowledging the essential issues related to e-logistics systems, a research model based on the theory acceptance model was designed and tested. The key factors to the e-logistics system (reliability, maintainability, software, facility and transportation) were validated through the modeling and testing process. Included in the modelling and testing process are other related factors of e-logistics process, logistics information system and added value as dependent variables in this model. The results of this study confirm that the e-logistics Process is affected by transportation, while maintainability and software factors influence logistics information system. reliability, maintainability, facility and transportation are significant factors associated with added value. This research aimed to provide theoretical and practical contribution to Chinese logistics companies and to give some insights into e-logistics system as a whole. The paper also provided some useful theoretical implication and practical guidelines for the development of e-logistics system in the chinese logistics industry.