• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.4
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• pp.406-414
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• 2004

In Gerotor pump, the pressure pulsations which occur due to the pump geometry result in vibration and noise of pump elements as well as cavitation in hydraulic system when the chambers of gerotor enter the delivery port and leave the suction port. Therefore it is important to study on the pressure pulsations before design and analysis of characteristics in Gerotor pump. In this paper, to reduce the unnecessary pressure pulsations, the port plate of Gerotor pump is designed based on the notch of the vane pumps and the relief grove of the piston pumps. The theoretical analysis of the pressure pulsations is performed in consideration of design parameters of the port plate which include each port positions and groove width and operating conditions which include rotational velocity and delivery pressure.

• Journal of Mechanical Science and Technology
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• v.20 no.10
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• pp.1626-1637
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• 2006

The pressure pulsation due to the gear geometry of the gerotor (generalized rotor) pump mainly occurs in an instant that the chamber of the gerotor enters the delivery port and leaves the suction one. Such a pressure pulsation may result in undesirable vibration and noise of pump components as well as cavitation in hydraulic system. Therefore, it is very important to examine the pressure characteristic of the gerotor pump at its design and analysis stages. In this paper, in order to reduce the pressure pulsation in the gerotor pump, the port plate with the relief grooves is designed by referring to as notch of vane pump and relief groove of piston pump. A series of the theoretical analyses on the pressure pulsation is performed in consideration of various design parameters of the port plate, including the installation positions of the port inlet/outlet and the groove width, and the operating conditions such as rotational velocity and delivery pressure.

• Journal of Navigation and Port Research
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• v.29 no.4
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• pp.305-312
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• 2005

Pick-up/delivery of consumer goods to offices, shops, and restaurants in order to support urban lives is one of the most vital activities in a city. With economic growth and technological innovation, a greater variety of goods have come to be supplied, and pick-up/delivery of consumer goods has become more complex. Efficient urban goods movement in Central Business District(CBD} starts with an efficient system for loading/unloading, and pick-up/delivery activities. Loading/unloading activity may be carried out on-street, or on especially designated space inside or outside buildings. Therefore, purpose of this study is to clarity the efficient urban goods movement in CBD(also called the pick-up/delivery activity) from the three different types of loading/unloading facilities. For this purpose, the differences in loading/unloading and truck-trip activity time of each loading/unloading facility was compared by performing the simulation analysis.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.58
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• pp.127-148
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• 2013

The Rotterdam Rules provide that port terminal operator may avoid or limit their liability for cargo loss, damage or delay in delivery or breach of any other obligation under the Rules by invoking the provisions that may provide a defence for, or limit the liability of, the carrier. Consequently the port terminal operator who are involved in the provision of maritime services may avoid or limit their liability for cargo loss, damage or delay in delivery or breach of any other obligation under the Rules. The port terminal operator to be applied for the Himalaya clause under the Rules must show that it has the requisite link with a Contracting State. In addition, the port terminal operator performs service to the period of time between the arrival of the goods at the port of loading and their departure from the port of discharge. The port terminal operator's liability for breaches of its obligation is limited to 875 SDR per package or other shipping units, or 3 SDR per kilogram of the gross weight of the goods. In addition, compensation for delay shall be limited to an amount equivalent to two and one-half times the fright payable on the goods delayed.

• Journal of Navigation and Port Research
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• v.37 no.3
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• pp.321-327
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• 2013

As the market of express delivery services expands rapidly, delivery service companies are exposed to severe competition. As a result of the surplus of delivery companies, they are struggling with remaining competitive at a reasonable price with appropriate level of customer satisfaction. To cope with competition pressures, a strategic alliance is suggested as an effective solution to the challenges faced by small and medium enterprises (SMEs) in express delivery services. Therefore, this study suggests a combined optimization and simulation approach to the reconfiguration of an express delivery service network for strategic alliance with respect to strategy partnership of closing/keeping service centers among companies involved and adjustments of their cutoff times. An illustrative numerical example is presented to demonstrate the practicality and efficiency of the approach.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2007.12a
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• pp.207-209
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• 2007

본 논문은 내륙 운송 체계 하에서 공 컨테이너의 효율적인 운송관리 문제에 대하여 다루었다. 내부적으론 pickup and delivery 제약조건을 적용하여 특정 pick up 시간을 가지는 화물과 터미널에서의 적 컨테이너을 만족하는 차량의 스케줄링 문제이다. 차량의 내부 운송에서 공 컨테이너의 이동이나 공차의 이동 같은 불필요한 이동을 최소화함으로 효율적 운송을 할 수 있다. 또 한 모든 화물과 수입된 적 컨테이너의 pick up time 의 시간 제약으로 인한 차량의 이동 제약를 만족해야 한다. 이 문제를 해결하기 위해서 휴리스틱과 메타 휴리스틱 방법을 이용하여 근사해를 도출한다.

• Journal of Navigation and Port Research
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• v.28 no.8
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• pp.679-685
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• 2004

Logistics needs in Asia are surprisingly increasing due to rapid growth of China Therefore, each country is trying to develop ports in order to attract logistics needs. Korea, also, begins to perform active port marketing policy, centering around Busan port and Kwangyang port, in order to become a logistics hub in Northeast Asia Recently, competitiveness of Japan has decreased due to increase in the inland transport costs, so Japanese is deliberating various counter plans. While Japan is stagnant, Korea has an opportunity for activating Busan port and Kwangyang port. This study estimates logistics costs by classifying types of delivery routes of Japanese imports and exports containers; that is, by dividing the case of using main ports in Japan, or Busan port and Kwangyang port. As a result, logistics costs are greatly reduced when the containers go by way of Busan port and Kwangyang port social and logistics costs.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2007.12a
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• pp.319-321
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• 2007

엘엔지운반선(LNGC)의 대형화에 따른 잇단 대형선의 건조과정을 살펴보고 향후의 발전과정을 살펴보도록 한다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2003.05a
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• pp.237-241
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• 2003

To improve competitive power of the container terminal, we must enhance the yark efficiency of a domestic container terminal in the chronic shortage situation, Therefore, we investigate the basic concept and the expected effect delivery reservation when applying at existing container terminal.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2012.10a
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• pp.63-64
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• 2012

2008년부터 시작된 세계경제 위축은 전 세계 해상물동량 감소로 이어져 컨테이너선업계의 불황이 더욱 심화되고 있다. 선사들은 불황을 극복하기 위하여 여러 가지 전략들을 구사하고 있다. 대부분의 선사들은 잉여 선박의 추가투입으로 감속운항을 통해 선박 운영비용을 절감하고 있는데, 이와 같은 시도는 선사입장에서는 비용절감이 되지만 감속운항이 화물의 정시성을 저해하는 요소로 작용하고 있기 때문에 화주입장에서는 불만요인이 될 수 있다. 이러한 상황에서 'M'선사는 "On Time Delivery"를 보증하기 위해서 아시아-유럽항로에서 새로운 서비스인 Daily Maersk Service를 2011년 10월부터 적용하고 있다. 본 서비스는 아시아발 북유럽행 특정 기간 포트구간 수송에서 100% "On Time Delivery"를 보증하고, 또한 매일 화물수탁을 가능하게 한 신서비스이다. 본 연구에서는 업계 1위를 달리고 있는 'M'선사가 감속운항을 하면서도 화물의 정시성을 높이기 위해 실시하고 있는 Daily Maersk Service를 통하여 가격 경쟁과 더불어 서비스 경쟁에서도 우위를 확보하려는 전략이 효과를 나타내고 있는 지에 대하여 사례연구를 통하여 확인하였다.