• 한국항해항만학회지
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• 제44권6호
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• pp.517-523
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• 2020

평택·당진항은 국내에서 가장 많은 완성차 물동량을 처리하는 항만으로 특히 수입 자동차는 국내 전체 물동량의 95% 이상을 처리하고 있다. 그러나 2015년부터 수입 자동차 물동량 증가가 정체되고 있어, 항만 개발이나 자동차 관련 산업에 투자를 계획하고 있는 관계자들에게 새로운 물동량 추정이 필요한 시점이다. 한편, 자동차 물동량 예측 시 그동안 GDP(국내총생산) 등 경제와 관련된 변수가 많이 활용되었으나, 선행연구를 통해 선진국에서는 이러한 경제관련 변수가 자동차 물동량에 미치는 영향이 점점 감소하고 있는 것으로 확인되었다. 특히 우리나라와 같이 짧은 시간내에 경제성장을 달성하고 선진국으로 진입한 경우에는 경제변수에 대한 주의가 필요하다. 이에 본 연구에서는 우리나라가 직면하고 있는 인구감소를 주요 요인으로 하여 시스템다이내믹스를 통해 평택·당진항의 수입 승용차 물동량을 예측하고자 한다. 예측결과 평택·당진항의 수입승용차 물량은 '21년을 기점으로 조금씩 감소하는 것으로 분석되었다. 그리고 예측된 결과값의 정확도를 측정하기 위해 MAPE 검증을 실시하였고, 수입 승용차 점유율에 대한 시나리로 분석을 실시하였다.

• 환경영향평가
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• 제7권1호
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• pp.109-116
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• 1998

As of July 1997, the registered number of automobiles exceeded 10 million and Korean auto industry produced 2,850,000 cars. Many environmentalists warn that the passenger cars are not sustainable urban transportation system in large cities. The cars produce about 80% of air pollutants, and consume 30% of petroleum imported. For the past 30 years the administration increased the road system, but the length of road per car is decreased from 813m in 1965 to 9m in 1995. The cost of traffic congestion was estimated to be \14.7 trillion in 1996, and is feared to increase without changing the present transportation system. The undesirable impact of cars include the casualties from traffic accidents, insurance loss, and separation of human relatioships. To construct sustainable urban transportation system, three principles should be followed. The first principle is to make the urban streets walkable for the people. The second principle is to encourage bicycling. Roads and traffic systems should be designed to let bicylces travel safely. The third principle is to supply more buses and construct integrated transportation system based on buses. The subway system is too expensive to construct and without the support of a well-organized bus system it may not work efficiently. The Brazilian city of Curitiba has constructed a very efficient bus system only with 1/80 of the estimated cost of subway system. The car-oriented transportation system does not seem to be an envrironmentally sustainable transportation system in most of the Korean cities.

• 드라이브 ㆍ 컨트롤
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• 제13권1호
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• pp.1-9
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• 2016

Nowadays automatic transmission equipped vehicles prevail in construction and agricultural equipment due to their convenience in driving and operation. Though domestic vehicle manufacturers install imported electronic controlled transmissions at present, overseas products will be replaced by domestic ones in the near future owing to development efforts over the past 10 years. For passenger cars, there are many kinds of shift control algorithms that enhance the shift quality such as feedback and learning control. However, since shift control technologies for heavy duty vehicles are not highly developed, it is possible to improve the shift quality with an organized control method. A feedback control algorithm for neutral-into-gear shift, which is enabled during the inertia phase for the master clutch slip speed to track the slip speed reference, is proposed based on the power transmission structure of TH100. The performance of the feedback shift control is verified by a vehicle test which is implemented with firmware embedded TCU. As the master clutch engages along the predetermined speed trajectory, it can be concluded that the shift quality can be managed by a shift time control parameter. By extending the proposed feedback algorithm for neutral-into-gear shift to gear change and shuttle shift, it is expected that the quality of the shift can be improved.