• Title/Summary/Keyword: Air cargo

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화물유 펌프실의 환기특성에 관한 연구 (A Study on Ventilation Characteristics of Cargo-oil pump room)

  • 박찬수;조대환
    • Journal of Advanced Marine Engineering and Technology
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    • 제24권1호
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    • pp.134-141
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    • 2000
  • In this study, a scaled model chamber was built to investigate ventilation characteristics of the Under floor Air-conditioning System. Experimental study was performed in model for cargo-oil pump room with inlet and outlet by visualization equipment with laser apparatus. Instant simultaneous velocity vectors at whole field were measured by 2-D PIV system(CACTUS'2000) which adopted two-frame grey-level cross correlation algorithm. The flow pattern reveals the large scale counterclockwise forced-vortex rotation from upside louver to lower scupper toward diagonal corner and also found small eddies at bottom layer

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ENVIROMENTAL CONDITION DURING AIR SHIPMENT OF HORTICULTURAL PRODUCTS FROM OKINAWA TO TOKYO

  • Akinaga, Takayoshi;Kohda, Yoshihiro
    • 한국농업기계학회:학술대회논문집
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    • 한국농업기계학회 1993년도 Proceedings of International Conference for Agricultural Machinery and Process Engineering
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    • pp.413-422
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    • 1993
  • Air shipment affords the quickest possible delivery of horticultural products. The price of air shipped horticultural products are relatively high as most of these products are perishable. Usually the temperature in the cargo compartment is not controlled during flight. Thus, special attention should be paid to procooling prior to shipment. The environmental condition during transportation of horticultural products is an essential parameter for maintaining the quality of perishable products. Commonly horticultural products were loaded by ULD(Unit Load Devices) as a container or pallet in the aircraft (except for small aircraft) . Therefore, inside temperature of the container and cargo compartment came into question. Scarce literature on the relationship between environmental condition and quality changes of horticultural products during air shipment can be found. By the stand point of keeping fresh quality, investigations on the actual condition of air shipments were carried out to improve the technique during the distribution process of fresh horticultural products. Temperature, humidity, atmospheric pressure, carbon dioxide, ethylene, impacts, and changes in quality during the air shipment of snapbeans, okras and chrysanthemums were measured. Temperature was measured by recording thermometers, relative humidity by recording hygrometers, atmospheric pressure by a strain -guage type pressure sensor, carbon dioxide by testing tubes, ethylene by sampling bags and a gaschromatograph, impacts and vibrations by impact recorders and a 3D accelerometer. Relationships between environmental conditions and quality changes during air shipments were clarified. It was expected from investigations into actual shipments that the ventilation and insulation properties of air freight containers were related to the quality of agricultural products. Aircraft can no directly load and unload trucks into them. The transshipment is inclined to cause shocks and vibrations, and to invite damages within a short time.

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인천국제공항의 21세기 동북아 중추공항으로서의 역할 (Inchon International Airport's Role in the 21st Century as Northeast Asia's Hub Airport)

  • 이선
    • 기술사
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    • 제34권1호
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    • pp.14-22
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    • 2001
  • Kimpo International Airport, located within the Seoul metropolitan district, experienced a sudden surge of passengers and cargo in recent years. In 1990, MOCT sponsored feasibility studios and Youngjong Island location was selected as the most suitable choice among four proposed sites to build a new airport. The construction work was then commenced in November 1992. Phase I project facilities are scheduled to start its operation in March 2001 with an annual capacity of 27 million passengers and 1.7 million tons of cargo for both enplaning and deplaning from International liners. Kimpo International Airport will remain in operation primarily for domestic passengers and cargo only. Phase II project construction work will add two more runways with its related facilities by 2005. Inchon International Airport will then conveniently serve 100 million passengers for enplaning and deplaning, and 7 million tons of inbound and outbound cargo annually in its full capacity. All the airport facilities In phase I and phase II periods are constructed to meet international standards. A fully integrated transportation network and logistics function systems should be accomplished prior to the full operation of the airport. With these sccomplishments, the state-of-the-art airport is poised to meet the needs of a rapidly growing worldwide air transport industry, and will more than adequately fulfill its role as a hub airport for the Northeast Asia region.

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A Scalable Heuristic for Pickup-and-Delivery of Splittable Loads and Its Application to Military Cargo-Plane Routing

  • Park, Myoung-Ju;Lee, Moon-Gul
    • Management Science and Financial Engineering
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    • 제18권1호
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    • pp.27-37
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    • 2012
  • This paper is motivated by a military cargo-plane routing problem which is a pickup-and-delivery problem in which load splits and node revisits are allowed (PDPLS). Although this recent evolution of a VRP-model enhances the efficiency of routing, a solution method is more of a challenge since the node revisits entail closed walks in modeling vehicle routes. For such a case, even a compact IP-formulation is not available and an effective method had been lacking until Nowak et al. (2008b) proposed a heuristic based on a tabu search. Their method provides very reasonable solu-tions as demonstrated by the experiments not only in their paper (Nowak et al., 2008b) but also in ours. However, the computation time seems intensive especially for the class of problems with dynamic transportation requests, including the military cargo-plane routing problem. This paper proposes a more scalable algorithm hybridizing a tabu search for pricing subproblem paused as a single-vehicle routing problem, with a column generation approach based on Dantzig-Wolfe decomposition. As tested on a wide variety of instances, our algorithm produces, in average, a solution of an equiva-lent quality in 10~20% of the computation time of the previous method.

Rapid response calculation of LNG cargo containment system under sloshing load using wavelet transformation

  • Kim, Yooil
    • International Journal of Naval Architecture and Ocean Engineering
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    • 제5권2호
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    • pp.227-245
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    • 2013
  • Reliable strength assessment of the Liquefied Natural Gas (LNG) cargo containment system under the sloshing impact load is very difficult task due to the complexity of the physics involved in, both in terms of the hydrodynamics and structural mechanics. Out of all those complexities, the proper selection of the design sloshing load which is applied to the structural model of the LNG cargo containment system, is one of the most challenging one due to its inherent randomness as well as the statistical analysis which is tightly linked to the design sloshing load selection. In this study, the response based strength assessment procedure of LNG cargo containment system has been developed and proposed as an alternative design methodology. Sloshing pressure time history, measured from the model test, is decomposed into wavelet basis function targeting the minimization of the number of the basis function together with the maximization of the numerical efficiency. Then the response of the structure is obtained using the finite element method under each wavelet basis function of different scale. Finally, the response of the structure under entire sloshing impact time history is rapidly calculated by synthesizing the structural response under wavelet basis function. Through this analysis, more realistic response of the system under sloshing impact pressure can be obtained without missing the details of pressure time history such as rising pattern, oscillation due to air entrapment and decay pattern and so on. The strength assessment of the cargo containment system is then performed based on the statistical analysis of the stress peaks selected out of the obtained stress time history.

국제항공운송협약의 Door to Door 운송에의 적용에 관한 문제점 (Problems on the Door to Door Application of International Air Law Conventions)

  • 최명국
    • 무역상무연구
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    • 제78권
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    • pp.1-29
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    • 2018
  • This article demonstrates that both the Warsaw Convention Systemand the Montreal Convention are not designed for multimodal transport, let alone for "Door to Door" transport. The polemic directed against the "Door to Door" application of the Warsaw Convention systemand the Montreal Convention is predominantly driven by the text and the drafting philosophy of the said Contentions that since 1929 support unimodalism-with the rule that "the period of the carriage by air does not expend to any carriage by land, by sea or by inland waterway performed outside an airport" playing a profound role in restricting their multimodal aspirations. The drafters of the Montreal Convention were more adventurous than their predecessors with respect to the boundaries of the Montreal Convention. They amended Art. 18(3) by removing the phrase "whether in an aerodrome or on board an aircraft, or, in the case of landing outside an aerodrome, in any place whatsoever", however, they retained the first sentence of Art. 18(4). The deletion of the airport limitation fromArt. 18(3) creates its own paradox. The carrier can be held liable under the Montreal Convention for the loss or damage to cargo while it is in its charge in a warehouse outside an airport. Yet, damage or loss of the same cargo that occurs during its surface transportation to the aforementioned warehouse and vice versa is not covered by the Montreal Convention fromthe moment the cargo crosses the airport's perimeter. Surely, this result could not have been the intention of its drafters: it certainly does not make any commercial sense. I think that a better solution to the paradox is to apply the "functional interpretation" of the term"airport". This would retain the integrity of the text of the Montreal Convention, make sense of the change in the wording of Art. 18(3), and nevertheless retain the Convention's unimodal philosophy. English courts so far remain loyal to the judgment of the Court of Appeal in Quantum, which constitutes bad news for the supporters of the multimodal scope of the Montreal Convention. According the US cases, any losses occurring during Door to Door transportation under an air waybill which involves a dominant air segment are subject to the international air law conventions. Any domestic rules that might be applicable to the road segment are blatantly overlooked. Undoubtedly, the approach of the US makes commercial. But this policy decision by arguing that the intention of the drafters of the Warsaw Convention was to cover Door to Door transportation is mistaken. Any expansion to multimodal transport would require an amendment to the Montreal Convention, Arts 18 and 38, one that is not in the plans for the foreseeable future. Yet there is no doubt that air carriers and freight forwarders will continue to push hard for such expansion, especially in the USA, where courts are more accommodating.

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중국효과와 해상/항공 복합운송 (China Effect and Sea/Air Intermodal Transport in Korea)

  • 김창범
    • 한국항만경제학회지
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    • 제23권2호
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    • pp.25-40
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    • 2007
  • 우리나라가 중국발 해상/항공화물 운송을 발전시켜 복합운송시장의 우위를 점한다면 중국교역의 물류거점지역으로 자리를 잡을 가능성이 있다. 이에 따라 본고는 중국경기가 해상 및 항공물동량에 미치는 효과를 통해 새로운 운송체계의 필요성을 제기하며, 우리나라 해상/항공 복합물류의 특성과 현황을 살펴본 후 활성화 방안을 제시하였다. 먼저 이동회귀분석 통해 해상물동량과 항공물동량 모두에서 경기계수가 시간의 흐름에 따라 작아지고 있으며, 해상물동량의 경우가 항공물동량보다 더 빠르게 중국경기의 영향력이 감소하고 있음을 알 수 있었다. 따라서 중국경제의 성장과 물동량 증가가 우리나라 해상물동량과 항공물동량 증가로 이어지는 구조가 악화될 수 있음을 나타내고 있다. 앞으로 새로운 운송체제의 구축이 필요함을 알 수 있었다. 그리고 해상/항공 복합운송의 활성화를 위해 해상/항공 복합운송 잠재수요의 파악 및 마케팅, 중국내 면허자격의 완화와 교차물류단지와 조성, 한 중간 해상운송시간의 단축, 통관시스템의 개선, 국적항공사의 항공기 스페이스 확보와 저렴한 운임을 제시하였다.

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항공화물 물류관리 서비스와 경영성과의 상관성: Forwarder의 수익률 효과분석 (Correlations between Air Freight Logistic Service and Business Performance of Forwarder)

  • 김중관
    • 통상정보연구
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    • 제16권1호
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    • pp.145-161
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    • 2014
  • 21세기에는 물류운송 시스템의 정보화가 국제적으로 이루어져서 항공화물운송에서도 화물운송 통합서비스가 구현되고 있다. 본 연구에서는 항공화물운송 관리체계의 핵심적인 연구 주제인 운송관리 시스템과 고객만족과의 상관성을 전제로 Forwarder의 수익률을 중심으로 경영성과의 상관성을 규명하였다. 소규모 운송관리 품질과 고객만족의 상관성 연구에서 기존에 연구주제로 채택되지 않았던 경영성과와 고객 만족도를 측정하였다. 연구목적의 달성을 위해 포워딩 이용 무역업체들을 대상으로 항공화물 운송관리 품질, 성과, 만족 관련 조사를 통하여 실증분석을 하였다. 항공화물의 운송과정의 제 단계에서 시스템의 서비스조건 측면의 운송관리 부분을 대상으로 성과변수를 단일항목으로 한정하여 측정하였다. 분석 결과, 국내 포워더의 운송시장에서 업무행태가 소비자 집단인 무역업체들의 업무에 긍정적인 영향을 주는 것으로 확인되었으며 이는 본 연구의 전제조건과 합치된다. 운송관리 품질 구성 차원들은 수익률 평가로 측정된 성과에 직접적인 영향을 주는 것으로 평가되었다. 아울러 성과는 고객만족에 긍정적인 영향을 주는 것이 분석되었다. 즉, 소규모 운송관리 품질은 화물위탁자의 만족도에 영향을 주는 한편, 성과를 통해 고객만족에 영향을 주는 것이 확인되었다. 이러한 분석결과는 항공화물 운송관리 상의 업무행태와 고객의 만족의 관계를 경영성과 측면에서 규명하였다는 점에서 실학적 가치를 극대화 하였으며, 운송실무 측면에서 포워더의 운송관리 시스템 향상을 위한 지속적인 투자의 타당성을 확보해준다는 측면에서 의미가 있다.

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