• 한국정보시스템학회지:정보시스템연구
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• 제24권2호
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• pp.97-116
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• 2015

Purpose This study suggested the four forms of inter-organizational relationships(IORs): partnerships, inter-dependence relationship, trust relationship, and market relationship. The purposes of this study include the demonstration of four forms of IORs and the investigation of the relationships among forms of IORs, inter-organizational information flow(IOIF), kinds of e-commerce strategies, and the supply-chain performance of a firm. Design/methodology/approach The empirical data were collected through post-survey. 92 survey data were collected. With a cluster analysis, we confirmed four types of IORs, and the relationships among critical variables. Findings The results of cluster analysis showed that according to the types of IORs, the frequency and quality of IOIF are different. Appropriate kinds of e-commerce strategies were examined under the each types of IORs, which cause specific patterns of IOIF. It was found that the adoption of e-procurement strategy can improve the supply-chain performance of a firm in trust relationship. It was also observed that under partnerships, the use of e-partnerships strategy can contribute to the improvement of supply-chain performance.

• 한국음향학회지
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• 제34권3호
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• pp.240-246
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• 2015

본 논문은 시간 연속성을 갖는 비음수 행렬 분해(Nonnegative Matrix Factorization, NMF)를 이용하여 잡음에 열화된 음성 신호의 음질을 개선하는 문제를 다룬다. 음성과 잡음 신호는 포아송 분포로 모델되며, NMF의 기본 벡터와 이득 벡터는 감마 분포로 모델된다. 이득 벡터의 시간 연속성은 음질 개선에 중요한 영향을 미치는 것으로 알려져 있다. 본 논문에서 시간의 연속성은 이득 벡터를 감마-마르코프 연쇄(Gamma-Markov chain, GMC) 사전 분포로 모델함으로써 이루어진다. 실험 결과는 제안된 알고리즘이 잡음 신호의 시간 연속성을 효과적으로 모델하는 것을 보여준다.

• 품질경영학회지
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• 제45권4호
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• pp.867-888
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• 2017

Purpose: This study suggests a SCQM model for the national Defense field based on earlier studies on the Quality Management of supply chain and to identify critical activities factors of supply chain that makes effect on the business results. Also, this study analyzed moderating effects of performance sharing between businesses which is becoming the big issues with regard to the supply chain cooperation. Methods: A causality of qm activities factor of SCQM model affecting benefit sharing and business performance was analyzed by using structural equation model. A company used in analysis performed a survey by targeting 297 Defense SMEs(weapon-system/non-weapon system). Results: As a result of analyzing the influence relationship between key activity of SCQM on finance performance, it was identified that Management Infra(MI), Process Management(PM), Human Resource Management(HRM), Performance Sharing activity(PS) made significant effect on Financial Performance, and Human Resource Management(HRM) and Performance Sharing(PS) activity made effect on non-financial Performance. Conclusion: The four variables(MI, PM, HRM, PS) of Defense SCQM were significantly effecting Financial performance and two variables(HRM, PS) were significant effected non-Financial performance. We also proved the moderating effect of performance sharing.

• 대한조선학회논문집
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• 제28권2호
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• pp.228-240
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• 1991

균열진전에 관한 많은 실험결과는 피로 균열진전 과정이 확률과정(stochastic process)임을 보여주고 있다. 따라서, 피로 균열진전에 관한 연구는 확률론적 기반에서 다루어져야 한다. 본 연구에서는 균열의 진전과정을 discrete Markov process로 가정하여, Bogdanoff가 제안한 Markov chain model(MCM)을 이용하여 구조물의 신뢰도를 평가할 수 있는 방법을 제시한다. 본 연구에서는 구조부재의 파괴형태로 누출, 소성붕괴 그리고 취성파괴를 취하였으며, 초기 균열크기의 변동성, 검사의 효과 등이 고려되었다. 또한, 불규칙 하중은 등가음력의 개념을 도입하여 처리하였다. 그리고, 구조물에의 계산례를 통하여 본 연구의 유용성을 보였다.

• International Journal of Naval Architecture and Ocean Engineering
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• 제11권1호
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• pp.178-201
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• 2019

The appropriate design of a mooring system to maintain the position of an offshore structure in deep sea under various environmental loads is important. Fatigue design of the mooring line considering OPB/IPB(out-of-plane bending/in-plane bending) became an essential factor after the incident of premature fatigue failure of the mooring chain due to OPB/IPB in the Girassol region in West Africa. In this study, mooring line fatigue analysis was performed considering the OPB/IPB of a spread moored FPSO in deep sea. The tension of the mooring line was derived by hydrodynamic analysis using the de-coupled analysis method. The floater motion time histories were calculated under the assumption that the mooring line behaves in quasi-static manner. Additional time domain analysis was carried out by prescribing the obtained motions on top of the selected critical mooring line, which was determined based on spectral fatigue analysis. In addition, nonlinear finite element analysis was performed considering the material nonlinearities, and both the interlink stiffness and stress concentration factors were derived. The fatigue damage to the chain surface was estimated by combining both the hydrodynamic and stress analysis results.

• Current Applied Physics
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• 제18권11호
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• pp.1313-1319
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• 2018

The coil-to-globule behavior of poly{${\gamma}$-2-[2-(2methoxyethoxy)ethoxy]ethoxy-3-caprolactone} (PMEEECL) as a ${\gamma}$-substituted poly (${\varepsilon}$-caprolactone) was investigated via atomistic molecular dynamics (MD) simulation. For this purpose, radius of gyration, end-to-end distance and radial distribution function of the chain in the presence of water were calculated. Consequently, the lower critical solution temperature (LCST) of PMEEECL chain at which the coil-to-globule transition takes place, was determined in each calculated parameter curve. The simulation results indicated that the LCST of PMEEECL was occurred at close to 320 K, which is in a good agreement with previous experimental results. Additionally, the appearance of sudden change in both Flory-Huggins interaction parameter (${\chi}$) and interaction energy between the PMEEECL chain and water molecules at about 320 K confirmed the calculated LCST result. The radial distribution function (RDF) results showed that the affinity of the PMEEECL side chain to water molecules is lower than its backbone.

• IMMUNE NETWORK
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• 제22권1호
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• pp.5.1-5.22
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• 2022

The approval of immunotherapies such as checkpoint inhibitors (CPIs), adoptive cell therapies and cancer vaccines has revolutionized the way cancer treatment is approached. While immunotherapies have improved clinical outcome in a variety of tumor types, some cancers have proven harder to combat using single agents, underscoring the need for multi-targeted immunotherapy approaches. Efficacy of CPIs and cancer vaccines requires patients to have a competent immune system with adequate cell numbers while the efficacy of adoptive cellular therapy is limited by the expansion and persistence of cells after infusion. A promising strategy to overcome these challenges is combination treatment with common gamma-chain cytokines. Gamma-chain cytokines play a critical role in the survival, proliferation, differentiation and function of multiple immune cell types, including CD8 T-cells and NK cells, which are at the center of the anti-tumor response. While the short halflife of recombinant cytokines initially limited their application in the clinic, advancements in protein engineering have led to the development of several next-generation drug candidates with dramatically increased half-life and bioactivity. When combining these cytokines with other immunotherapies, strong evidence of synergy has been observed in preclinical and clinical cancer settings. This promising data has led to the initiation of 70 ongoing clinical trials including IL-2, IL-7, IL-15 and IL-21. This review summarizes the recent advancements of common gamma-chain cytokines and their potential as a cancer immunotherapy.

• Industrial Engineering and Management Systems
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• 제15권4호
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• pp.385-395
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• 2016

Game theory is a powerful tool for analyzing the Supply chain (SC) with different conflicting elements. Among them, the Stackelberg game is the one in which a player as leader has more power than the other ones as followers. Since in many SC systems one element has, in essence, more power than the others; the Stackelberg game has found many applications in SC studies. In this paper, we apply the Stackelberg game-theoretic approach and the corresponding equilibrium point to formulate and analyze a two echelon VMI SC. Comprehensive computational results on an experimental case are conducted to numerically analyze the performance of VMI system against three groups of critical parameters. Moreover, a critical comparison demonstrates the poorer performance of decentralized VMI system than centralized one. This naturally necessitates designing proper contracts between VMI partners in order to more effectively implement the realistic decentralized system.

• 한국건설관리학회논문집
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• 제5권5호
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• pp.84-92
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• 2004

건설 공사의 여러 관리 요소 중 일정관리는 매우 중요하다. 하지만 현재의 건설 프로젝트 일정관리 수준은 1950년대에 만들어진 PERT나 CPM을 반세기가 지난 지금까지 그대로 사용하고 있을 정도로 후진성을 면치 못하고 있다. 이런 PERT/CPM의 사용은 소요공기추정의 불확실성과 그 활동에 할당된 자원의 경합과 같은 여러 가지 문제들을 야기하고 있다. 따라서 본 연구에서는 기존의 일정관리 기법인 PERT/CPM의 단점을 보완하고 국내 건설공사의 일정관리 효율성을 증대시키기 위하여, 1997년에 개발된 새로운 일정관리 이론인 CCPM(Critical Chain Project Management)에 대한 소개와 함께, 가상의 교량건설 프로젝트를 대상으로 한 모의시험을 통하여 CCPM의 국내건설사업에의 적용 가능성을 검증 하였다.

• 한국해양공학회지
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• 제31권4호
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• pp.299-307
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• 2017

The design of the mooring line to maintain the position of an offshore structure in rough marine environments is recognized as a very important consideration. Conventional fatigue evaluation of a mooring line was performed by considering the tensile force acting on the mooring line, but the mooring line broke after 238 days in the girassol area even though the expected fatigue life was expected to be longer. The causes of this event are known to be due to OPB/IPB (out-of-plane bending/in-plane bending) caused by chain link friction due to the excessive tensile strength of the mooring line. In this study, three models with different boundary conditions were proposed for fatigue analysis of a mooring line considering OPB/IPB. Interlink stiffness was calculated by nonlinear structure analysis and a stress concentration factor was derived. In addition, the sensitivity of interlink stiffness according to the magnitude of tensile force, large deformation effect, and coefficient of friction was analyzed, and the effect of critical elastic slip and bending moment calculation position on interlink stiffness was confirmed.