• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 춘계학술대회 논문집
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• pp.1324-1332
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• 2008

The change of the transportation circumstance related to the deep environmental pollution, escalation of the energy price, increasing social cost of the congestion and traffic accident, improving a income level, advanced social structure etc, is rapidly proceeded. For the corresponding this transportation circumstance, the role of the railway is being increased and that is friendly with environment, efficient for the energy, observed the time schedule and the transportation device which is high speed and safe mass transportation. In addition, government's R&D investment is being increased according to deeping a strength of the international competitiveness through the technical innovation. So railway's R&D investment is being increased. Accordingly, This study suggest improving a fruit of the R&D related to railway R&D system for a efficient R&D investment.

• 기술사
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• 제45권5호
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• pp.26-35
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• 2012

Korea is now the 12th largest economy in the world, surpassing its annual trade in the amount of $1 trillion, and it has joined the socalled 20-50 Club, becoming one of the seven countries in the world with capita income of more than $20,000 with population of 50 million. However it ranked 24th of the Global competitiveness index evaluated by World Economic Forum based on the basic requirements including infrastructures, efficiency enhances, innovation and sophistication factors, etc. The extensive and efficient SOC infrastructures are critical for ensuring the global competitiveness of each country. Effective modes of SOC facilities including quality roads, railroads, ports, air transport, etc will be able to reduce the annual traffic congestion cost as well as macro economic logistics costs in Korea, thereby the global competitiveness can be strengthened in the global market.

• 대한전기학회논문지:전력기술부문A
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• 제51권7호
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• pp.311-316
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• 2002

It has been a basic model for the present electric power industry that more than two generators compete, and thereby the market clearing price and the generation schedules are determined through the bid process. In order for this paradigm to be applicable to real electric power systems and markets, it is necessary to reflect many physical and economic constraints related to frequency and transmission in the dispatching schedule. The paper presents an approach to deriving a Nash bargaining solution in a competitive electricity market where multiple generators are playing with the system operator who mitigates the transmission congestion to minimize the total transaction cost. In this study, we take the effect of the line flows and the role of system operator into the Game. Finally, a case study has been demonstrated to verify the proposed cooperative game.

• 한국시뮬레이션학회논문지
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• 제6권1호
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• pp.97-108
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• 1997

For the purpose of decreasing economic loss from the traffic jam, a car route guidance system efficiently utilizing the existing roads has attracted a great deal of attention. In this paper, the search algorithm for optimal path and alternative paths, which is the main function of a car route guidance system, was presented using evolution program. Search efficiency was promoted by changing the population size of path individuals in each generation, applying the concept of age and lifetime to path individuals. Through simulation on the virtual road-traffic network consisting of 100 nodes with various turn constraints and traffic volumes, not only the optimal path with the minimal cost was obtained, avoiding turn constraints and traffic congestion, but also alternative paths with similar costs and acceptable difference was acquired, compared with optimal path.

• 정보와 통신
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• 제10권8호
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• pp.77-87
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• 1993

There has been increasing attention paid to the influence of fascimile type of technologies on transportation costs. This attention is noticeable in large business companies, as fascimile become widely available in Korea. The importance of the fascimile usage is that it might effectively substitute for transportation, thereby reducing transportation costs. This paper presents an analysis of cost saving resulting from fascimile usage for substitutable trips. Data were collected from business companies on various aspects of the fascimile usage patterns, with particular emphasis on usage behavior substitutable for trips. Although by no means comprehensive, the analysis revealed that significant benefits can be derived from the usage of fascimile for substitutable trips in business settings. The results of benefit estimation show that net benefits turn out to be 7,608 won and 5,055 won per one usage for large and small companies respectively. If traffic congestion were to be considered, total social benefits would be higher.

• 한국항해항만학회지
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• 제29권9호
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• pp.795-800
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• 2005

Nowadays, road transportation which has played a key role in the market of both passenger and freight transportation is facing with a serious problem, the traffic congestion causing a delay of transportation. Therefore, railroad transportation is considered as an attractive alternative mode of inland transportation due to its inherent merits in mass transportation such as relatively low cost compared with road transportations, less air pollution and noise than other mode ets. In this paper, therefore, we examine the current situation of railroad transportation markets including TKR(Trans- Korean Railway}, TSR(Trans-Siberian Railway} and prospects for the connection of TKR-TSR. And then we examine the structure of the container transportation market by railroad in Korea with a brief analysis of the traffic volume of TKR-TSR.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권12호
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• pp.6123-6138
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• 2018

Named data networking (NDN) is a new network architecture designed for next generation Internet. Router-side content caching is one of the key features in NDN, which can reduce redundant transmission, accelerate content distribution and alleviate congestion. However, several security problems are introduced as well. One important security risk is cache privacy leakage. By measuring the content retrieve time, adversary can infer its neighbor users' hobby for privacy content. Focusing on this problem, we propose a cache privacy protection mechanism (named as CPPM-DAM) to identify legitimate user and adversary using Bloom filter. An optimization for storage cost is further provided to make this mechanism more practical. The simulation results of ndnSIM show that CPPM-DAM can effectively protect cache privacy.

• Structural Engineering and Mechanics
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• 제90권3호
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• pp.301-311
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• 2024

Different methods have been proposed in the literature for splicing the reinforcing bars in the construction of concrete structures, which are alternatively used depending on design requirements. The most common approach is the lap splicing which is known as a cost-effective method although, its main disadvantages including congestion of bars at the lap zone and consequently, material wastage has motivated utilization of the other techniques such as mechanical splices (couplers). To better evaluate the performance of the couplers, 6 reinforced concrete (RC) beams whose difference is only the type and location of splices have been experimentally studied in this paper. Based on the results, the mechanical connection of the bars did not markedly affect the load-carrying capacity of the specimens. Moreover, it was observed that after applying the loads and failure of the specimens, none of the bars ruptured at the splice location and all couplers remained undamaged.

• 한국ITS학회 논문지
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• 제6권2호
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• pp.57-69
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• 2007

도시 내 물류 활동과 관련하여 직면한 중요한 문제 중 하나는 교통체증 심화에 따른 수송효율성 저하이다. 이러한 교통체증의 심화는 화물차량의 평균 통행속도를 감소시켜 운행효율을 저하시키는 것은 물론 수송비용을 증가시켜 궁극적으로 물류비 증가를 초래하고 있다. 이러한 물류비의 상승은 선진물류체계로 전환하는 과정에 있어서 장애가 되는 주요 원인으로 작용하고 있다. 따라서 본 연구에서는 대부분 자가용 화물차량이 1톤 이하의 소형트럭임을 감안할 때 이러한 자가용 화물차량의 증가가 교통 혼잡의 원인이 되어 수송비 증가와 그에 따른 물류비 상승으로 연결되는 문제를 해결하기 위해 실측 조사된 RP (Revealed Preference)자료를 이용한 로지스틱 회귀분석으로 영업용 화물차량 선택에 영향을 주는 요인을 분석하고자 하였으며, 이에 따른 영업용 화물차량 이용 장려 정책을 제시하고자 한다.

• 한국정보통신학회논문지
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• 제7권2호
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• pp.214-227
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• 2003

어플리케이션을 개발하는 데 있어서 전통적인 텍스트 기반의 방법으로는 정확한 요구사항을 파악하기 어렵다. 그리고 각 개발 단계에서의 분석과 확인에 관한 문제점이 있다. 그러므로 만약 검증에서 에러와 요구사항의 교환이 요구된다면 모든 시스템에 나쁜 효력이 발생할 수 있다. 이 경우 개발비용과 기간에 불리하게 작용한다. 따라서 분석과 검증은 에러가 자주 일어나는 것을 방지하기 위해서 수행한다. 본 논문에서는 각 개발 단계에 대한 분석과 확인 그리고 그래픽 인터페이스를 제공하는 SDL을 이용한 TCP/IP 혼잡제어 알고리즘에 대해서 논한다. SDL을 사용함으로써 각 개발 단계에 대한 명확한 표현과 정확한 에러 또는 요구사항 교환에 검증을 쉽게 할 수 있다. 추가적으로 프로토콜의 단계는 MSC의 확인을 통해서 시뮬레이션으로 확인하고 결론에서는 TCP/IP 프로토콜보다 개발의 가능성을 보인다.