• 품질경영학회지
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• 제43권3호
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• pp.221-238
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• 2015

Purpose: In this study, A reliability assurance model (or reliability program) is proposed to evaluate the reliability of an armed vehicle. The reliability assurance is performed through the reliability-centered activities during its life cycle of development/design, production, deployment, maintenance, and disposal. Methods: By reflecting the current situations of korea defense industry, a reliability assurance model is built up based on the benchmarking results of world leading companies' best practices in same fields. Results: The proposed reliability program of armed vehicles, which is based on the reliability program of ANSI/GEIA-STD 0009, uses DMAIC process of the six sigma methodology from design phase to testing and evaluation phase. Conclusion: This research is supposed to develop reliability program of armed vehicles by integrating DFSS, DFR and reliability growth process.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2011년도 춘계학술대회 논문집
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• pp.735-741
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• 2011

In the early phase of vehicle development, CAE is conducted as tool for vehicle performance assessment. To maintain acceptable road noise performance, solution for reduced vehicle sensitivity is required. Chassis interface dynamic stiffness characteristics are key component to isolating vibration and noise of road from the vehicle interior. This research provide how to set up the optimized dynamic characteristics under noise effect through DFSS study. CAE-based DOE is performed to build prediction math model, CMS process involves DOE to achieve very fast run times while giving results very comparable. Minimized $95^{th}$ percentile of performance distribution is applied to minimize vehicle sensitivity and road noise levels variation during the optimization process. Finally, the results of optimization were reviewed for performance and robustness.

• The Plant Pathology Journal
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• 제29권1호
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• pp.59-66
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• 2013

Colonization studies previously performed with a green-fluorescent-protein, GFP, labeled derivative of Bacillus amyloliquefaciens FZB42 revealed that the bacterium behaved different in colonizing surfaces of plant roots of different species (Fan et al., 2012). In order to extend these studies and to elucidate which genes are crucial for root colonization, we applied targeted mutant strains to Arabidopsis seedlings. The fates of root colonization in mutant strains impaired in synthesis of alternative sigma factors, non-ribosomal synthesis of lipopeptides and polyketides, biofilm formation, swarming motility, and plant growth promoting activity were analyzed by confocal laser scanning microscopy. Whilst the wild-type strain heavily colonized surfaces of root tips and lateral roots, the mutant strains were impaired in their ability to colonize root tips and most of them were unable to colonize lateral roots. Ability to colonize plant roots is not only dependent on the ability to form biofilms or swarming motility. Six mutants, deficient in abrB-, sigH-, sigD-, nrfA-, yusV and RBAM017410, but not affected in biofilm formation, displayed significantly reduced root colonization. The nrfA- and yusV-mutant strains colonized border cells and, partly, root surfaces but did not colonize root tips or lateral roots.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2003년도 학술대회지
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• pp.129-138
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• 2003

Rolling bearings are classified one of the most important machine elements. The various function of bearings are greatly influenced by grease, and higher performance of rolling bearing greases is required in improve bearing lubrication. Three urea/ether oil greases with identical composition were synthesized to compare the performance of these greases according to the thickener content of grease. The typical grease physical properties were investigated. And life test of these greases was conducted by FE-9 grease life tester. The characteristics of the greases before and after life test were investigated using FT-IR, microscope, OIT and TAN meter. Large differences in the grease performance depending on the content of the thickener were observed. The grease with higher content of the hickener showed higher performance such as long life time and low TAN value. After preliminary test, twelve greases were synthesized and evaluated the performance of dropping point and OIT, then optimized two greases were selected by SSRED (Six Sigma Robust Engineering Design) using dropping point and OIT data. Characteristics of the optimized two greases were on the same level with estimated value. The optimized grease by means of OIT value showed longer grease life in comparison with optimized grease by dropping point. However two greases showed higher performance than typical urea/ether oil.

• 인터넷정보학회논문지
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• 제7권6호
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• pp.21-40
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• 2006

지식 기반 사회가 구축되면서 처리해야 할 업무 프로세스의 규모가 커지고 분석할 정보의 양이 증가함으로 인해 프로세스 관리와 개선에 대한 필요성이 높아지고 있다. 본 논문에서는 비즈니스 프로세스 관리를 위해 프로세스 수행에 필요한 명확한 규칙과 정의를 관리하는 룰 에이전트를 적용하여 프로세스의 정확한 수행을 가능하게 하고 일정관리 에이전트를 적용하여 프로세스 수행에 투입된 개개인의 일정을 정확하게 측정하고 관리할 수 있도록 했다. 에이전트를 적용한 프로세스 관리 모델은 조직 차원에서 비즈니스 프로세스의 자동화와 프로세스 중복 제거를 통한 프로세스의 통제성, 유연성, 민첩성, 신뢰성, 재사용성을 높이고 개인 차원에서는 개인의 프로세스 역량을 측정하고 프로세스 개선점을 식별하여 개선할 수 있도록 설계 및 구현하였다.

• 한국대기환경학회지
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• 제8권3호
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• pp.155-161
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• 1992

A simple, fast yet sensitive method is described for the determination of fifty elements in coal by inductively coupled plasma mass spectrometry. The method involves complete dissolution of coal with mixed acid $(HNO_3, HF, HClO_4)$ in hish pressure Teflon bomb and subsequent inductively coupled plasma mass spectrometric(ICP-MS) measurement. The accuracy of the method, being evaluated by the analysis of NIST SRMs (1632a, 1632b) is better than 20% RSD for most elements. The limits of detection defined by two times $\sigma$ (standard deviation of operational blank) are in order of sub-ppm to ppm, which are low enough to quantitate most elements. However, the determiantions for few elements such as V, As, Se are severely interfered by molecular ions such that their accurate determiantions are not possible. Analytical results for twentyon coals from eight countries including six ones world major coal producing, Korea, Japan, China, I.C.S., U.S.A., Canada, Australia, and South Africa are presented. While the results for major elements agree well with the existing ones, those for a few trace elements disagree considerably. The existing values are considerably higher. It is not possible to judge which are more accurate. However, the exisisting values are more likely to be errorous inasmuch as they are obtained without using high purity reagents and clean laboratory techniques.

• 자동차안전학회지
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• 제7권1호
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• pp.27-32
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• 2015

In order to protect occupant during car crash accident, Regulation and NCAP(New Car assessment Program) have been developed among various countries like U.S.A., Europe, Korea and Australia. Especially NCAP scores affect to sales of vehicles. So vehicle makers are trying to get good score in NCAP. Low leg injuries play an important role in Australia and Euro NCAP and these injuries are related with footrest design. Optimization of footrest design in early stage of vehicle development is necessary to obtain better and robust results of low legs during crash tests. In this paper, DFSS method and finite element model were used to optimize the low leg performance in small RHD vehicles. Compared with the lower leg injury of base model, the lower leg injury of proposed model was slightly improved and robustness was enhanced also.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 2004년도 추계학술대회 및 정기총회
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• pp.35-38
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• 2004

Global competitive pressures are asking industrial companies to find the best way to meet their customer's requirements, reduce the costs of products, and increase productivity. Quality improvement has been proposed and implemented as a primary means of achieving these purposes. The quality improvement usually includes a goal of reducing the costs due to poor quality. While these costs of poor quality (COPQ) are not known precisely, they are known to be very high. Also, they may be underestimated by the hidden costs due to non-value activities, such as potential lost sales, costs of redesign due to quality reasons, and extra manufacturing costs due to defects, etc. In any manufacturing or service operation, all actions and resource expenditures of a company should be focused on creating value for customers. Any activity or resource of not creating the value for customers could be regarded as waste, which consequently causes the COPQ. Some companies did use dashboards to understand and identify value added or non-value added activities in order to reduce or eliminate wastes. These dashboards must be properly designed to consider inherent differences in manufacturing or service operations among business organizations. In addition, a structured quality improvement program such as the Six Sigma must support these dashboards. In this paper, a case study of designing dashboards for evaluating and reporting the COPQ in business units is presented.

• 한국분무공학회지
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• 제17권3호
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• pp.140-145
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• 2012

Recent common-rail injector of a diesel engine needs more smaller nozzle hole to meet the stringent emission regulation. But, small nozzle hole diameter can cause nozzle coking which is occurred due to the deposits of post-combustion products. Nozzle coking has a negative effect on the performance of fuel injector because it obstructs the fuel flow inside a nozzle hole. In this study DFSS (Design for six sigma) method was applied to find the effect of nozzle design parameter on nozzle coking. Total 9 injector samples were chosen and tested at diesel engine. The results show that nozzle hole diameter and K-factor have more effect on nozzle coking than A-mass and hole length. Large hole diameter and A-mass, small hole length and K-factor give more positive performance on nozzle coking in these experimental conditions. But, a performance about nozzle coking and exhaust gas emission shows the opposite tendency. Further study is needed to find the relation between nozzle coking and emission characteristic for the optimization of injector nozzle design.

• 산업공학
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• 제16권spc호
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• pp.116-122
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• 2003

We analyze how much employees' work abilities and overall satisfaction on the job or corporate influence on the productivity and customer satisfaction in the service industry, which is characterized by simultaneity, heterogeneity, intangibility and etc. Employees always encounter customers in process of the service. So, the employees' attitudes and behaviors have direct influences on the service quality or satisfaction which customers perceive. Also, employees' satisfaction or work abilities can lead to increase or decrease the productivity. To grasp and demonstrate the cause and effect relationship, we firstly measure the degrees of employee satisfaction organized by 11 factors through survey, and also measure employees' overall satisfaction, organizational commitment and productivity. Secondly, we define service value as the employee's objective measure index and collect it with the data related to customer satisfaction. Based on the collected data, thirdly we define how the relationship among the employee satisfaction, the productivity, the service value and the customer satisfaction are affected by the employees' work abilities and overall satisfaction with SEM(Structural Equation Model). And finally, we classify employees according to their abilities and the degrees of satisfaction respectively and suggest important strategies to manage them effectively.