• Journal of Korea Port Economic Association
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• v.22 no.3
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• pp.189-207
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• 2006

As the development of Northeast Asian logistics hub becomes one of the national agenda for further development, the sea&Air transport around the Yellow Sea regions has drawn attention of many scholars and government officials. The Sea&air transport is a mode of transportation combining the advantage of high-speed in air transport with the advantage of low-price in sea transport. Hence the sea&air aims at a niche market between air and sea. This paper reviews the possibility of development of the sea&air transport in the aspects of competitiveness over other modes, future demand condition, and the change of the technology and transport environment. The result is that the sea&air is competitive in the aspect of time as well as cost, and sustainable in the aspect of future demand condition. But, it is not stable in the aspect of the conditions of technology or transport demand. Especially, the progress of air transport technology which is aiming at the door-to-door transport among mid- and small- cities, and the rapidly increasing strategic alliances of international airlines with Chinese airlines for the market of China will undermine the stability of the sea&air transport seriously As alternatives, this paper proposes the 3-stage development strategy of sea&air transport. First, at the stage of transshipement, the development of high speed vessels to reduce the time crossing the Yellow Sea and the proactive marketing strategy to induce Chinese-owned products should be emphasized. Second, the value added logistics activity which will secure the demand of the sea&air transport should be developed. Third, demand creation by developing the SCM hub in Incheon is final goal for the logistics hub strategy as well as the sea&air transport.

• Journal of the Korean Society of Propulsion Engineers
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• v.3 no.1
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• pp.104-117
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• 1999

The Composite materials has been used in the field of high technology industry because of high specific stiffness and high specific strength. Specially, the composite materials has been widely applied to the field of the aircraft and the transportation by the effectiveness of light weight due to low specific weight and reduction of the parts due to bonding, molding and so on. These advantages about the composite have led to study and apply in the transmission shaft for the aircraft and the drive shaft for the automobile. The composite material propeller shaft with the high vibrational stability was designed and analyzed. In order to verify the analysis, two types of experimental test which are the FFT analyzer with impact hammer and the rotational equipment were applied.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.217-218
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• 2003

지구의 기후변화는 자연, 인위적인 요인 모두에 의해서 발생되지만 UN IPCC는 "인간의 활동에 의해 발생되는 온실가스가 자연적인 기후변화에 단독으로 미치는 영향보다도 복합적으로 작용하여 현재보다 휠 씬 더 지구온난화 등 기후변화를 가속화시키고 있다"고 하여 인위적인 요인의 중요성을 시사하고 있으며, 인위적 온실가스 배출량의 상당부분은 에너지산업, 제조/건설업, 수송 등의 연료연소부문에서 기인하고 있다. (중략)

• Bulletin of the Korea Photovoltaic Society
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• v.5 no.1
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• pp.7-15
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• 2019

최근 유기물과 무기물의 복합된 구조를 가지는 페로브스카이트 소재를 광흡수층으로 사용한 태양전지가 연구적으로 큰 관심을 받고 있다. 이러한 유무기 하이브리드형 페로브스카이트 소재는 기존의 광흡수 소재들에서는 발견되지 않던 독특한 광전기적인 특성과 이에 기인하는 고 광전변환효율 그리고 저렴한 박막제조 공정 등으로 인해 기존 차세대 태양전지의 한계에 돌파구를 제시하고 있다. 본 글에서는 이러한 고효율, 고안정성 페로브스카이트 태양전지 구현을 위해 사용되는 전하수송소재의 종류와 개발동향에 대해서 살펴보고자 한다.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.2075-2089
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• 2008

Improvement of transport system is necessary to advance the freight traffic meanwhile logistics are getting bigger and faster by worldwide tendency. The link between each transportations occurs bottleneck state and it raises the necessity of non-stop mixed transport system which can reduce the cost of logistics. DMT(Dual Mode Trailer) was designed to use road and railway at the same time for door to door service. It is called DMT for every transport system which can connect between road and railway in Korea. This study would like to examine the present condition of promotion for localization of DMT which is new idea and technology and suggest the new subjects from now.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.5
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• pp.173-181
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• 2013

This paper proposes a heuristic optimal solution of multicommodity transportation problem. The proposed algorithm has 3 steps. First the proposed algorithm transforms multicommodity transshipment problem to a general transportation problem, but if the problem is a multicommodity transportation problem, it is not transformed. And the multicommodity is disassembled to a single commodity. Second if it is a multicommodity transportation problem, the algorithm selects the minimum cost according to commodity, on the other hand if it is a multicommodity transshipment problem, the algorithm directly selects the minimum cost based on demand area. And the algorithm assigns carloadings to be satisfied the supply and demand quantity. The algorithm repeats these processes until a given demand quantity is satisfied. Last if it has a condition that is able to reduce the transportation expense, the proposed algorithm controls the assignment quantity of the initial value that got from the step 2. The proposed algorithm was applied to two multicommodity transportation problem and three multicommodity transshipment problem and it got more good result than an existing linear programming method.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2005.05a
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• pp.348-352
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• 2005

본 논문은 조선소에서 계획기간동안 각 플랜트의 생산일정에 따른 블록의 모든 수송요구량이 미리 알려져 있는 정적인(static) 수송환경을 고려한 트랜스포터 일정계획문제를 다룬다. 조선소 내에서 블록들의 수송은 몇 가지 특성을 가진다. 500톤을 초과하는 거대 블록들은 2대 이상이 결합된 새로운 형태의 트랜스포터를 이용하여 운반된다. 운반이 요구되는 블록들 중 일부는 계획기간동안 규정된 출발요구시각에 pick-up되기를 요구하는 반면 나머지 블록들은 계획기간동안 규정된 도착요구시각 전에 delivery되기를 요구한다. 이러한 트랜스포터의 결합 및 시간 제약은 문제를 더욱 복잡하게 하는 요인이 된다. 본 논문에서는 계획기간 내에 모든 블록운반 요구사항들(출발지와 도착지, pick-up과 delivery 시각, 톤수, 결선 등)을 만족시키는 트랜스포터 일정계획문제를 다룬다. 트랜스포터 일정계획문제에서 중요한 주제는 총 로지스틱스 시간 (공차운행시간, delay 시간 및 tardy 시간)을 최소화하기 위해 계획기간 내에 최소의 트랜스포터 운영대수로 각 트랜스포터에 어떤 블록을 할당하고 어떤 순서로 운반할 것인 지를 결정하는 것이다. 이에 본 논문에서는 주어진 트랜스포터 일정계획문제를 해결하기 위해, 1단계에서 최소비용 네트워크 흐름문제를 근간으로 트랜스포터의 최소사용대수를 구하고 이를 기초로 2단계에서 각 트랜스포터에의 블록 할당과 운반순서를 결정하는 2단계 휴리스틱 알고리즘을 제안한다.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.3268-3277
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• 2011

Uiwang ICD, which is the only inland container depot in the capital area, is equipped with modern facilities, and loading and unloading equipment, and can handle 1,000,000 TEU annually.It has many advantages such as advantageous conditions of location, the role of foothold for distribution transportation in the capital area, so it plays an important role of vitalizing the railroad transport. However, Uiwang ICD has reached the limit in the vitalization of railroad transport of containerized cargo due to the current problems in facilities and operations. This research analyzed the Uiwang ICD's problems by dividing them into facilities problems and operational problems, and presented short-term and medium and long-term improvement measures with the year 2023 when the private use permission expires as the basic year. However, the vitalization of railroad transport of Uiwang ICD can be attained only when it has support and cooperation from the government, Uiwang-si, Korea Rail Network Authority, and other related organizations together with efforts of Korea Railroad Corporation, and occupant companies. Such improvement measures for Uiwang ICD are expected to contribute to establishing combined transport system and forming efficient railroad distribution infrastructures and vitalizing railroad distribution, and also contribute to the government's low-carbon green growth policy by building environment-friendly transport system.

• Journal of Korean Society of Transportation
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• v.25 no.5
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• pp.111-122
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• 2007

This paper investigates the rail service patterns by train class. The emphasis in intercity rail planning is to more efficiently use of existing station facilities. Rail transit operations are affected by the system layout and ridership patterns and by work rules. Operations are also influenced by past practices and the institutional setting. Main factors to decide train service patterns are the location, socioeconomic characteristics, land use and travel demand of the station. In this context, the travel demand of intercity rail station is of crucial significance. Tests on a KTX case shows that train service frequency can be efficiently decreased in weekday to transport the same passenger demand. The work has shown many subjects that need further research including various factors influencing on train frequency. This study serves the railroad authorities in planning and determining business strategy in the increasingly competitive environment of regional rail transport.

• Journal of Korean Society of Transportation
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• v.3 no.1
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• pp.94-104
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• 1985

도시부의 활동이 지방부의 그것과 크게 다른점은 토지이용의 집약도가 높은 데 있 다 하겠다. 지금까지 도시부 토지이용의 밀도변위등에 관계되는 사정은 잘 인식되어 오기는 하였으나 이를 실용적 모형으로 다룬 예는 극히 드물다. 본 논문은 다양한 수송수단을 포용 하는 교통망에서의 혼잡비용이 토지이용의 집약도에 따라 효과적으로 결정될 수 있도록 하 는 토지이용과 교통의 복합모형을 제시하였다. 이를 위하여 다품종교통류 및 I/O모형의 범 주에서 비선형계획의 접근방법이 채택되었다.