• Proceedings of the Korean Information Science Society Conference
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• 2003.04d
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• pp.575-577
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• 2003

다양한 인터넷 응용분야에서 사용자와 서비스 제공자간에 서비스 수준 계약(SLA, Service Level Agreement)을 체결하여 차별화된 서비스를 제공하고자 하는데, 계약 조건의 대표적인 예는 일정시간 내에 서비스를 제공반기 위한 서비스 지연시간과 같은 시스템 성능 척도이다. 따라서 본 논문에서는 클러스터 시스템 환경에서 차별화된 서비스 제공을 위한 알고리즘을 제안하고 이에 대한 가용도 분석을 통해 성능 척도와 가용도 사이의 상관관계를 박히며, 성능 향상을 위한 고려사항을 제시한다.

• Proceedings of the Korean Nuclear Society Conference
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• 1997.05b
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• pp.636-642
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• 1997

원자력 수출시 적용되어야 할 여러 가지 통제지침을 분석하고 원자력 수출제도상의 문제점을 살펴보았다. 한국 표준형 원자력 발전소의 해외진출에는 외적요인으로 제3국에 재 이전시 원공급국의 사전동의권과 원자력관련 국제협약이나 제도상 부과된 공급조건의 이행보장을 당사국으로부터 받아야 하는 점이다. 이에 대한 최선의 해결책은 공급국과 수입국 사이에 원자력협력협정을 체결하는 것이다. 국내 원자력 수출체제의 개선점으로는 원자력 전용품목에 대한 수출허가 절차의 개선과 원자력 통제품목의 재 이전에 대한 대비책이다. 원자력해외진출에 기존 원자력 선진국의 영향을 최소화시키기 위해서는 국제적인 원자력 통제지침의 이행을 통하여 대외 신뢰도를 구축해 나아감과 동시에 해외공동 진출을 모색하는 것이 최선이라고 사료된다.

• 한국디지털정책학회:학술대회논문집
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• 2004.05a
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• pp.205-228
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• 2004

오늘날 정보와 정보서비스 나아가 정보거래는 경제의 중심에 그 자리를 잡아가고 있다. 이러한 변화중의 하나가 방법의 다양화이다. 현대적 시장의 수요를 충족하는 정보제품을 제작하고 이를 배포함에 있어 그 방법의 다양화가 이루어지고 있는 것이다. 개인용 컴퓨터의 사용이 일반화됨에 따라 범용컴퓨터소프트웨어가 일반소매시장에서 거래되는데, 사용자는 이를 대부분 소프트웨어 상점에 매매의 형식으로 구입한다. 그러나 이 소프트웨어를 사용하기 위해서는 사용자가 동 소프트웨어의 출판인(publisher) 으로부터 라이센스를 득해야 하고, 이를 위해 출판인과사용자 사이에 라이센스 계약이 체결된다. 이러한 라이센스계약의 체결에 있어 소위 "쉬링크랩" (shrink-warp) 방식이 널리 사용되는데, 이 방식의 라이센스계약, 즉 쉬링크랩 라이센스 혹은 쉬링크랩라이센스계약이 미국 계약 법하에서 완전한 효력 즉 강제력을 가지는 지가 문제되어 왔다. 쉬링크랩라이센스는 소프트웨어거래의 효율성을 높이고 거래비용을 감소시킴으로써 규모의 경제를 가능케 하고 나아가 다양한 지적재산권의 보호를 받는 소프트웨어의 탄력적인 라이센스를 가능케 함으로써 결국 소프트웨어출판인과 최종사용자 모두가 그 혜택을 누리게 된다. 쉬링크랩라이센스에 의한 소프트웨어 거래의 경우 라이센스이용자에 의한 대금지급이 선행하고 그 이후에 비로소 계약조건의 검토가 행하여진다는 사정에 기하여 종래 판례법에서 그 강제력이 부인되어 오다가 정보 산업의 급속하게 성장하고 이에 따라 그 사용에 불가피하다는 현실적인 요구에 응하여 판례법은 물론 UCITA 라는 제정법에 의하여 그 강제력을 인정받게 되었다. UCITA 는 컴퓨터소프트웨어 등의 컴퓨터정보거래와 관련하여 체결되는 라이센스 계약의 모호한 법적 상태를 명확히 한다는 점에서 중요한 입법이라 평가된다. UCITA 는 쉬링크랩라이센스의 효력 문제와 동 라이센스에 적용될 법의 해결이라는 통일법으로서의 주요한 목적 중의 하나를 달성하고 있다. 더욱이 오늘날 우리 경제는 소위 정보혁명(information revolution) 이라 하는 또 다른 근본적 변화를 경험하고 있다.

• Journal of Korean Society of Steel Construction
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• v.9 no.3 s.32
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• pp.301-307
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• 1997

In field fabrication of steel members, the oversize hole is frequently required due to reaming and mismatching. But, there are no provisions and investigations about oversize hole in the Korean specifications. So, in this study, the tension test of friction type high-tention bolted joints is performed with parameters of bolt hole size, surface treatment and tightening force, and investigate the effect of slip behavior with those parameters. From the results, the enough tightening force is needed to obtain some degree slip load in shot blast treatment case, although tightening force is reduced somewhat, it is no problem to guarantee slip load in zincrich primer case. The slip behavior of joints with oversize hole(26mm) is similar to the slip behavior of joints with hole of nominal size.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.38 no.11
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• pp.1115-1122
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• 2010

The main objective of this study is to experimentally investigate the effect of adhesive thickness and environmental conditions on the failure and strength of sandwich-to-laminate bonded joints. Three different adhesive thicknesses (t=0.2, 2 and 4 mm) and two different environmental conditions were considered. Environmental conditions include the RTD(room temperature and dry condition) and ETW(elevated temperature and wet condition). Test results show as the adhesive thickness increases from 0.2 mm to 2 and 4 mm, the joint strength decreases 16 and 30%, respectively. Regarding the effect of environmental conditions, except for one case, the joint strength in the ETW conditions turned out to be 12% higher than those in the RTD conditions. In the joints with adhesive thickness of 0.2 mm, remarkable difference from RTD condition was not found.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.10 no.3
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• pp.39-46
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• 2011

The automotive air conditioning hose is used for connecting the components of air conditioner in a vehicle. The hose is usually manufactured by the swaging process to connect the rubber hose with the metal fitting at the end of the hose. In case that the clamping force is small, the refrigerant gas in the hose can leak locally under the severe operating circumstances. The practical test of clamping force is performed by means of the measurement of separation force. In this study, the swaging process of a hose is simulated with the finite element method, to investigate the effect of friction coefficient on the clamping force. The contact condition is used in consideration of real manufacturing process, and the material properties for the Mooney-Rivlin model is obtained by the experimental results. The result interpretations are focused on the contact forces, which is displayed graphically with respect to friction coefficient, on the surfaces between the hose and the metal fittings.

• Korean Business Review
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• v.12
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• pp.303-321
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• 1999

Electronic commerce, driven by the development of the Internet and computer, premises to be an important engine for growth for the world economy in th the 21st century. Electronic commerce offers considerable new opportunities for the business and citizens in all regions of the world by enhancing productivity across of our economics and encourage trade in both goods and services. Specially in relation to contract, electronic commerce requires a coherent, coordinated approach internationally on key issues such as a validity, a legality, consumer protection. Electronic commerce, which breaks down national boundaries and widens the gap between the place where services are performed and the place where they are consumed, requires a new paradigm when making an between contracting parties.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.35 no.7
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• pp.601-611
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• 2007

Most of mechanically jointed aircraft structures are always encountered the fretting damages on the contact surfaces between two jointed structural members or at the edges of fastener holes. The partial slip and contact stresses associated with fretting contact can lead to severe reduction in service lifetime of aircraft structures. Thus a critical need exists for predicting fretting crack initiation in mechanically jointed aircraft structures, which requires characterizing both the near-surface mechanics and intimate relationship with fretting parameters. In this point of view, a series of fretting fatigue specimen tests for 2024-T351 Al-alloy, have been conducted to validate a mechanics-based model for predicting fretting fatigue life. And included in this investigaion were elasto-plastic contact stress analyses using commercial FEA code to quantify the stress and strain fields in subsurface to evaluate the fretting fatigue crack initiation.

• Composites Research
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• v.28 no.6
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• pp.348-355
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• 2015

NDT (Non Destructive Test) of the adhesive joints is very important because their strengths have greatly affected by the worker's skill and environmental condition. Recently, the electric impedance method in which 1-2 wt% CNT was dispersed in the adhesive and the electric resistance of the adhesive joint was measured was suggested for the defect detection of the adhesive joint. The uniform dispersion of CNT in the electric impedance method is very important to make a constant electric resistance of the adhesive joint and the accuracy of defect detection depends on the uniform dispersion. In this paper, the adhesive joints in which CNT was dispersed in the adhesive by the four dispersion methods were made and their electric resistance were measured. The pre-process and evaporation process of CNT using the ultrasonic method and agitation method was used and the effective dispersion method was suggested. Also, the criteria to evaluate the dispersivity was proposed.

• The Journal of the Convergence on Culture Technology
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• v.7 no.2
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• pp.405-410
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• 2021

In this study, a finite element analysis was performed applying a nonlinear material model and fatigue load conditions to evaluate the service life and spring stiffness of the resilient pad for rail fastening system. As a result of the fatigue analysis, the rate of change in spring stiffness compared to the initial condition was about 16%, indicating that fatigue hardening occurred. As for the stress generated in the longitudinal direction of the resilient pad, the difference between the stress generated at the center and the edge was about 10 times or more. In addition, it was analyzed that the equivalent stress of the outer boundary was more than twice as large as that of the central part. Therefore, it was analyzed that the damage and deformation of the resilient pad are the corners of the resilient pad under actual service conditions. The fatigue life diagram of the resilient pad (S-N curve) was derived using the equivalent stress of the resilient pad according to the fatigue cycles. Using the fatigue life diagram of the resilient pad derived in this study, it is considered that it can be used to predict the fatigue life under the relevant conditions by calculating the equivalent stress of the resilient pad under various load conditions.