• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.496-501
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• 2007

Recently, as MEMS and NEMS devices have been widely used in the various engineering applications, the characteristics of nanoscale systems are investigated in the limelight. However, as opposed to a macroscale system, the identification of the state of nanoscale systems is extremely hard because they can include only the order of $10^{3}\sim10^{5}$ molecules, which requires highly expensive and accurate experimental apparatus for an investigation. This limitations make the study on nanoscale system use computer simulations. Therefore, it is strongly required to identify the state of nanoscale system simulated in computer simulation. In these molecular dynamics(MD) study, we suggest that the potential energy of individual molecule can be used as criterion for defining the state of clusters or nanoscale systems. In addition, we compared the phase state from the potential energy with one from the radial distribution function(RDF) for verification. The comparison showed that the intermolecular potential energy can be used as a criteria distinguishing the phase state of nanoscale systems (This study will be published soon in the KSME transaction of the section B).

• 전력전자학회논문지
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• 제6권1호
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• pp.82-89
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• 2001

본 논문은, HVDC 시스템의 인버터 제어기 및 고조파 필터의 설계를 위하여 동특성 및 정상상태 특성을 해석하는 방법을 제시한다. EMTP 시뮬레이션을 이용하면, 동특성 분석이 가능하며, 정상상태 특성의 분석은필터와 부하를 고려한 조류해석을 수행함으로써 가능하다. 또한 본 논문은 HVOC 시스템의 정적 및 동적 특성 분석이 가능한 단상 등가회로를 제안한다. 이 단상 등가회로에서 인버터는 스위치의 소호에 따른 전류원으로 취급된다. 또한 필터설계에 사용되고 있는 각종 목적함수를 단상 등가회로룹 이용하여 구할 수 있다, 본 논문은 전압의 고조파 성분 및 필터의 전력손실을 고려한 목적함수를 이용하여 펄터를 최적화하는 과정이 제시되어 있다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 19-21 Oct. 1992
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• pp.281-284
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• 1992

This paper is aiming to apply the Genetic Algorithms (GAs) to the interactive design. For that purpose, the scheme for utilizing the past design processes for the next interactive design process is proposed. In this scheme, the process consists of three phases: the searching phase, the tuning phase and the design phase. The first phase searches the optimal decision sequences for the past design instances by GAs. By the collected sequences, the second phase tunes the criteria of selecting decision sequences for the next design process. By this scheme, the implicit constraints satisfied in the past design can be applied to the next design. Finally, the computer simulations on the simple gear-train design were carried out to show the effectiveness of the scheme.

• Korean Journal of Radiology
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• 제21권4호
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• pp.471-482
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• 2020

Objective: We aimed to determine the optimized image-based surrogate endpoints (IBSEs) in targeted therapies for glioblastoma through a systematic review and meta-analysis of phase III randomized controlled trials (RCTs). Materials and Methods: A systematic search of OVID-MEDLINE and EMBASE for phase III RCTs on glioblastoma was performed in December 2017. Data on overall survival (OS) and IBSEs, including progression-free survival (PFS), 6-month PFS (6moPFS), 12-month PFS (12moPFS), median PFS, and objective response rate (ORR) were extracted. Weighted linear regression analysis for the hazard ratio for OS and the hazard ratios or odds ratios for IBSEs was performed. The associations between IBSEs and OS were evaluated. Subgroup analyses according to disease stage (newly diagnosed glioblastoma versus recurrent glioblastoma), types of test treatment, and types of response assessment criteria were performed. Results: Twenty-three phase III RCTs published between 2000 and 2017, including 8387 patients, met the inclusion criteria. OS showed strong correlations with PFS (standardized β coefficient [R] = 0.719), 6moPFS (R = 0.647), and 12moPFS (R = 0.638). OS showed no correlations with median PFS and ORR. In subgroup analysis according to types of therapies, PFS showed the highest correlations with OS in targeted therapies for cell cycle pathways (R = 0.913) and growth factor receptors and their downstream pathways (R = 0.962). 12moPFS showed the highest correlation with OS in antiangiogenic therapy (R = 0.821). The response assessment in neuro-oncology criteria provided higher correlation coefficients between OS and IBSEs than the Macdonald criteria. Conclusion: Overall, PFS is an optimized IBSE in targeted therapies for glioblastoma; however, 12moPFS is optimal in antiangiogenic therapy.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2002년도 춘계학술발표대회 논문집
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• pp.163-166
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• 2002

For the development of an all composite unmanned aerial vehicle (UAV), manufacturing consideration in design phase, works for composite parts fabrication, subassembly and final assembly are summarized. In design phase, to maximize the advantage of composite material, manufacturing processes such as cocuring, cobonding and secondary bonding are introduced. For the curing of designed parts, composite tools are designed and manufactured. Assembly jigs are designed to satisfy dimensional tolerance of the structure. Inspection criteria are established and applied to the manufacturing. Technical data about inspection items and methods are summarized as manufacturing specifications for the mass production of the UAV structure.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1987년도 전기.전자공학 학술대회 논문집(II)
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• pp.1445-1448
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• 1987

The phase-only filter (POF) to the classical matched filter is compared for the criteria of discrimination, correlation peak, and optical efficiency in Korean alphabet. In addition, logarithmically scaled POF is presented to improve the recognition efficiency and this shows the superior performances in English alpanumeric characters to Korean.

• 시스템엔지니어링워크숍
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• 통권1호
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• pp.60-64
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• 2003

In this study, we have analyzed the cost of korea high-speed railway system. The predicted cost in planning phase and adjustment data to 5th year are collected. Then, predicted cost is compared with adjustment in year/item/system base. We make a project history table for criteria to review project history and research & development activity. We have developed CBS(cost breakdown structure) and allocated adjustment data to them. It is shown that cost prediction related to research & development activity in planning phase is relatively correct.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 추계학술대회 논문집(I)
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• pp.376-381
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• 2002

In this study, we have analyzed the cost of korea high-speed rail project. The predicted cost in planning phase and adjustment data to 5th year are collected. Then, predicted cost is compared with adjustment in year/item/system base. We make a project history table for criteria to review project history and research ＆ development activity. We have developed CBS(cost breakdown structure) and allocated adjustment data to them. It is shown that cost prediction related to research St development activity in planning phase is relatively correct.

• The Journal of Advanced Prosthodontics
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• 제8권3호
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• pp.187-193
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• 2016

PURPOSE. This pilot study was to find the influence of complete denture on the brain activity and cognitive function of edentulous patients measured through Electroencephalogram (EEG) signals. MATERIALS AND METHODS. The study recruited 20 patients aged from 50 to 60 years requiring complete dentures with inclusion and exclusion criteria. The brain function and cognitive function were analyzed with a mental state questionnaire and a 15-minute analysis of power spectral density of EEG alpha waves. The analysis included edentulous phase and post denture insertion adaptive phase, each done before and after chewing. The results obtained were statistically evaluated. RESULTS. Power Spectral Density (PSD) values increased from edentulous phase to post denture insertion adaption phase. The data were grouped as edentulous phase before chewing (EEG p1-0.0064), edentulous phase after chewing (EEG p2-0.0073), post denture insertion adaptive phase before chewing (EEG p3-0.0077), and post denture insertion adaptive phase after chewing (EEG p4-0.0096). The acquired values were statistically analyzed using paired t-test, which showed statistically significant results (P<.05). CONCLUSION. This pilot study showed functional improvement in brain function of edentulous patients with complete dentures rehabilitation.

• 대한안전경영과학회지
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• 제14권2호
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• pp.245-252
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• 2012

The biggest difficulty the small and small business currently face is not to have the effective cusomer management system that is the computerization of management. This suggests their will to introduce data marketing in order to differentiate 'Customer Marketing' and 'One to One Marketing'. The potential needs as well as visible needs of customer should be considered in order to research and analyze the customer data. At this point mayor enterprises are paying much attention to Customer Segmentation and their related markets are expanding rapidly. I'll give a brief introduction to the Multi Criteria Importance-Performance Analysis and go into the problems that should be considered and which phase to emphasize when building this system.