• KSCE Journal of Civil and Environmental Engineering Research
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• v.44 no.3
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• pp.375-383
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• 2024

The size of the construction industry is increasing, and its impact on the entire national industry is also significant. However, construction cost increases, construction period delays, safety accidents, and quality problems occur during the construction process. This paper analyzed the construction cost, construction period, and change order performance for civil infrastructures for which post evaluation was performed. The analysis was conducted by dividing civil engineering facilities by type, construction nature, construction cost, contract nature, and delivery method. Planned and actual construction cost and period were compared during the planning, design, and construction process of civil engineering facilities. There is a possibility of input errors in project performance data, this paper proposes to the post-evaluation center should perform post-evaluation. Also, post-evaluation implementation guidelines for change orders should be revised. Additionally, further analysis of each facility was proposed through continuous data collection.

• Electronics and Telecommunications Trends
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• v.26 no.4
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• pp.175-181
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• 2011

이동망 착신독점력 규제를 위해 각국 규제당국은 이동망 착신접속료(Mobile Termination Rate: MTR)를 원가기준으로 규제하고 있다. 원가기준으로는 과거 FDC 방식이 채택되어 왔으나 2002년 영국이 "LRIC+" 방식으로 MTR을 결정한 이래 "LRIC+" 방식이 EU를 비롯한 OECD 주요국의 MTR 산정방식으로 보편화되어 왔다. 그러나 2009년 EU에서 순수증분비용(Pure Long Run Incremental Cost) 방식으로 착신접속료 규제방식 변경을 권고하는 권고안을 채택함으로써 EU 가맹국은 Pure LRIC 방식으로 MTR을 변경하여야 한다. 본 고에서는 Pure LRIC 방식 채택을 권하는 EU 권고안 채택 배경, Pure LRIC 산정 방법론, EU 권고안에 대한 각국의 이행계획을 살펴보며, Pure LRIC 채택이 가져올 영향을 살펴보고자 한다.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2006.07a
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• pp.376-376
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• 2006

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.4
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• pp.201-209
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• 2020

In this study, issues related to changes in base year, which have controversial effects on fees in service contracts, were reviewed. In this regard, sensitivity analysis was conducted on the effects of changes in base year on conversion factor by type. The benefits and disadvantages of each specific type of medical institution were examined. Main conclusions are as follows. First, changing the base year to be closer to the present time had a beneficial effect on the conversion factor of hospitals. Second, changing the base year to be closer to the current point of time had an adverse effect on the conversion factor of pharmacies and clinics and had a significant adverse effect on clinics. Third, assuming that a single conversion factor is collectively applied to all types, a favorable effect occurred in all cases when the base year was changed to be closer to the present time. Base year changes can bring about conflicts of interest between insurer and providers, and within providers. Therefore, changing the base year should be pursued upon mutual agreement on a reasonable basis for resource allocation. In addition, it is necessary to provide incentives for temporary compensation for the types of losses incurred.

• Journal of Korean Society of Transportation
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• v.28 no.1
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• pp.97-105
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• 2010

An All-red clearance interval(AR) has been operating with amber signal in order to avoid collision between vehicles which cannot come out of the intersections, vehicles coming in from the opposite direction, and pedestrians(bicycles) on the crosswalk during the signal conversion time at the intersections. Foreign nations have been analyzing AR's influences of traffic accidents. On the other hand, the similar research has not been conducted in the country. The objective of this paper, therefore, is to analyze the safety at the intersections with respect to the installation of AR through the hypothesis test. A before-and-after analysis has been performed for 10 intersections where applied AR. From the 95% of significance level, the results of Non-parametric Test show that the installation of AR improves a safety at the intersections. The results indicates that AR discharges vehicles passing through the intersections and control entering vehicles at the intersections.

• The Journal of Society for e-Business Studies
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• v.13 no.4
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• pp.93-110
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• 2008

Reference modeling for Collaborative Networked Organizations(CNOs) has just started, and Enterprise Architecture Modeling Languages(EAMLs) for CNOs are very few. Lack of reference models makes it difficult for people to communicate with each other and lack of EAMLs also makes it difficult to implement information systems for CNOs. We propose an EAML for CNO called CAML. It supports (1) multi-level modeling based on Model- Driven Architecture of OMG's for expressive power and efficiency of implementations, and (2) multi-focus modeling based on Zachman Framework for completeness of modeling The effectiveness of the CAML is investigated through modeling of a supply chain and execution of change impact analysis.

• Journal of Digital Contents Society
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• v.14 no.2
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• pp.179-189
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• 2013

With the rapid development of information technology in 21st century, networks are being used with various devices. Most human actions are processed through cyber space, and it is no longer separate from daily life; it has changed into one of the most important aspects of human life. Unfortunately, in cyber space, certification method has not only technical problems, but also ethological problems. Many users seemed to use the same password throughout several sites. And for a long period they refused to change it or made a small change from the earlier password. This research aims to discuss general factors of choosing and using passwords within information security through statistical analysis.

• Electronics and Telecommunications Trends
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• v.13 no.1 s.49
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• pp.14-20
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• 1998

본 논문은 대도시 전화망에서 루팅 효과, 통화량에 준한 망설계기법에서 전송시설의 경제적 규모, 그리고 투자비용 변화를 분석하기 위한 시뮬레이션 모델 개발에 관한 것이다. 모의시험 결과는 전화망에서 교환/전송에 소요되는 비용은 루팅방식의 변경에 따라서 크게 영향을 받으며, 고속 전송로 사용에 따른 규모의 경제효과가 클수록 망 구축에 소요되는 비용이 현저히 작아지는 것으로 나타났다.

• Korean Chemical Engineering Research
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• v.60 no.4
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• pp.512-518
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• 2022

In this study, safety devices for ammonia tanks of a company in Ulsan petrochemical industrial complex were studied. The type of a tank is cylindrical and this tank was originally designed to store propylene in 1972. Due to the changes of the production schedule according to market environments, the usage of this tank has been changed to store ammonia. Despite of the changes of materials, there is no scientific information or reviews for guaranteeing the safety. Therefore, in this study, the current status of this tank is investigated to confirm that the operational conditions are complying with safety conditions. Moreover, the safety devices such as an ammonia absorbing system and water curtains are analyzed how they mitigate the impact of an accident. In addition, consequence analysis is performed to provide a proper emergency response plan. Throughout these analysis, it is confirmed that installed safety devices effectively mitigate the impact of accidents, and the necessary time for an emergency response plan is suggested when ammonia release.

• Proceedings of the Korean Information Science Society Conference
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• 2003.04d
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• pp.439-441
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• 2003

사용자의 인터넷 환경이 점차 무선 접속을 통한 인터넷의 사용과 실시간 응용 데이터의 사용이 늘어가는 추세에 따라. 이동 인터넷 서비스를 하기 위한 방안으로 Mobile If와 Mobile IPv6가 제시되었다. 본 논문에서는 Mobile IPv6 환경에서 Neighbor Discovery 중 Router Solicitation과 Router Advertisement가 호스트의 이동성 지원에 미치는 영향을 분석하였다. Neighbor Discovery 메시지들의 주기를 변경하여, 실제 구현, 측정하여 Handoff의 효율성과 전송 대역폭 overhead의 상관관계를 알아보았다.