• Title/Summary/Keyword: Maritime transport

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Permission of Costal Carriage of Import-Export Containers by Ocean Liner Carriers and Growth Plan of Costal Shipping Industry (외항선사(外航船社)의 수출입(輸出入) 컨테이너 내항운송(內航運送) 허용(許容)에 따른 문제점(問題點)과 내항해운(內航海運)의 육성방안(育成方案))

  • Ha, Yeong-Seok;Chung, Keun-Jon
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.19
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    • pp.96-118
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    • 2003
  • Government tries to revise the article 25 in Korea Maritime Transport Act which describes subject of coastal carriage for exported-imported container cargoes. The subject of coastal carriage will be replaced coastal carrier by ocean liner carrier according to the revised article 25. By adopting the revised article, coastal shipping industry will be deteriorated in terms of returns on investment, sales and etc. Even though the revision is inevitable to harmonize the flow of exported-imported container cargo movement, coastal shipping industry should be developed and restructured to get competitive power and to set up an efficient international logistics system. To enhance competitive power of coastal shipping companies successfully, government must realize the importance of coastal shipping, and aid the industry through various methods such as arrangement of law and regulation, indirected financial assistance, decrease of tax rate, etc.

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Power Management of Open Winding PM Synchronous Generator for Unbalanced Voltage Conditions

  • EL-Bardawil, Ashraf;Moussa, Mona Fouad
    • Journal of Power Electronics
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    • v.16 no.6
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    • pp.2192-2201
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    • 2016
  • Wind energy is currently the fastest-growing electricity source worldwide. The cost efficiency of wind generators must be high because these generators have to compete with other energy sources. In this paper, a system that utilizes an open-winding permanent-magnet synchronous generator is studied for wind-energy generation. The proposed system controls generated power through an auxiliary voltage source inverter. The VA rating of the auxiliary inverter is only a fraction of the system-rated power. An adjusted control system, which consists of two main parts, is implemented to control the generator power and the grid-side converter. This paper introduces a study on the effect of unbalanced voltages for the wind-generation system. The proposed system is designed and simulated using MATLAB/Simulink software. Theoretical and experimental results verify the validity of the proposed system to achieve the power management requirements for balanced and unbalanced voltage conditions of the grid.

Globalization and Consolidation in Maritime Transport and Its Implications for Container Port Business

  • Ryoo Dong-Keun
    • Journal of Navigation and Port Research
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    • v.29 no.9
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    • pp.801-806
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    • 2005
  • The world of container shipping and container terminal business is changing and container ports need to know what the changes are in order to plan how to respond. In particular, the container transport industry has noticed two major developments such as globalization and consolidation. The purpose of this paper is to review the current trend towards globalization and consolidation of container liner shipping and container terminal business. It also investigates the impact of these market developments on container ports and presents its implications for port development, management and operation, and port competition policy. According to the discussion of this paper a greater exercise of market power of container terminal operators will have negative impacts on international trade and national economy, especially port users, including container lines, exporters and importers. An empirical evidence on the exercise of market power is required to develop competition rules on market dominance at a national and international level. This paper suggests 'port coopetition' as a solution for smaller and regional container terminal operators to survive in a competitive business environment.

Gaza Seaport as a Way to Enhance the Palestinian Economic Development

  • Hassouna Abdallah;Nam Ki-Chan
    • Journal of Navigation and Port Research
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    • v.29 no.9
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    • pp.813-819
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    • 2005
  • The purpose of this paper is to present some main economic factors which influence Gaza Seaport. Without direct access to the international market, the Palestinian economy will continue its dependence on Israeli economy mainly in employment, transport facilitation, and international trade. The greatest potential for Palestinian economic growth lies in trade. The port is important for creating new job opportunities, and for enhancing exporting capabilities, which are the most essential elements for development of the Palestinian economy. Israeli policies and procedures incur Palestinian exporters additional transportation costs when delivering their products to Israeli Ports or when transit these products to neighboring countries through Israeli controlled area. The public profit for the port is greater than the private profit. Therefore, constructing the port will have a great effect on the Palestinian economy. There are many challenges facing the port, some of them are the political stability, the economies of scale, and Israeli security measures and procedures.

Prediction of a transverse shrinkage of butt welded joints in shipyard conditions using the design of experimental approach

  • Urbanski, Tomasz;Taczala, Maciej
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.12 no.1
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    • pp.784-798
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    • 2020
  • This paper presents the results of research on transverse shrinkage of welded butt joints conducted according to the principles of experimental design and under production conditions for two main welding techniques used in shipbuilding (FCAW and SAW). Analysis took into account the technological and structural parameters influencing the assembly suitability of a large steel structure. The presented method of evaluation makes it possible to apply approximation formulae to predict transverse shrinkage in real sections of a ship hull. The determined predictive formulae were verified to actual transverse shrinkage measurements during prefabrication of hull sections at a shipyard as well as the equations referring to the analyzed form of deformation available in the literature.

Numerical investigation of an add-on thrust vector control kit

  • AbuElkhier, Mohamed G.;Shaaban, Sameh;Ahmed, Mahmoud Y.M.
    • Advances in aircraft and spacecraft science
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    • v.9 no.1
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    • pp.39-57
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    • 2022
  • Instead of developing new guided missiles, converting unguided missile into guided ones by adding guidance and controlkits hasbecome aglobaltrend.Ofthemost efficient andwidelyused thrust vector control(TVC) techniquesin rocketry isthe jet vanes placed inside the nozzle divergentsection. Upon deflecting them, lift created on the vanesistransferred to the rocket generating the desired control moment. The presentstudy examinesthe concept of using an add-on jet vaneTVC kit to a plain nozzle.The impact of adding the kit with different vaneslocations and deflectionanglesisnumericallyinvestigatedbysimulatingtheflowthroughthenozzlewiththekit.Twohingelocations are examined namely, at 24% and 36% of nozzle exit diameter. For each location, angles of deflection namely 0°, 5°, 10°, and 15° are examined. Focus is made on variation of control force, thrust losses, lift and drag on vanes, jet inclination, and jetflow structure withTVCkit design parameters.

The Change of Beach Processes at the Coastal Zone with the Impact of Tide (조석(潮汐)의 영향(影響)이 있는 연안(沿岸)해역(海域)에서의 해안과정(海岸過程)의 변화(變化))

  • Kim, Sang-Ho;Lee, Joong-Woo
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2002.05a
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    • pp.257-262
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    • 2002
  • Numerical model introduced in this study combines wave refraction-diffraction, breaking, bottom friction, lateral mixing, and critical shear stress and three sub-models for simulating waves, currents, and bottom change were briefly discussed. Simulations of beach processes and harbor sedimentation were also described at the coast neighboring Bangpo Harbor, Anmyundo, Chungnam, where the area has suffered from accumulation of drifting sand in a small fishing harbor with a wide tidal range. We also made model test for the case of a narrow tidal range at Nakdong river's estuary area to understand the effect of water level variation on the littoral drift. Simulations are conducted in terms of incident wave direction and tidal level. Characteristics of wave transformation, nearshore current, sediment transport, and bottom change are shown and analyzed. We found from the simulation that the tidal level impact to the sediment transport is very important and we should apply the numerical model with different water level to analyze sediment transport mechanism correctly. Although the model study gave reasonable description of beach processes and harbor sedimentation mechanism, it is necessary to collect lots of field observation data, including waves, tides and bottom materials, etc. for better prediction.

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Dune Migration on an Offshore Sand Ridge in the Southern Gyeonggi Bay, Korea (경기만 남부지역 사퇴 위에 발달된 dune의 이동)

  • Kum, Byung-Cheol;Shin, Dong-Hyeok
    • Ocean and Polar Research
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    • v.35 no.1
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    • pp.51-61
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    • 2013
  • Two surveys were conducted in January 2006 and September 2007 with multibeam echosounder to investigate the dune shape, migration rate, and bedload transport rate using dune-tracking method on an offshore sand ridge at southern Gyeonggi Bay. The migration rates of dunes range from 1.8 $myr^{-1}$) to 56.0 $myr^{-1}$), at the upper northwestern side of sand ridge towards the southwest direction and from the center of the sand ridge towards the northeast direction respectively. Large (i.e. length 10-100 m) dunes show faster migration (0.3-23.4 $myr^{-1}$) ) than very large (i.e. length > 100 m) dunes because larger dunes have required a larger volume of sediments to be displaced. The decreases in dimensions and migration rates of dunes from the center of sand ridge to the lower part of southeastern side on the sand ridge can be ascribed to the decrease of sandy sediments availability, tidal currents with depth, and the coarsening of surface sediments from the crest of the sand ridge to the trough. Bedload transport rates on the basis of migration rates and dune dimensions decrease from 74.5 $m^2yr^{-1}$) at C transect to 35.6 $m^2yr^{-1}$) at R-02 transect.

Changes in Block Exemption Applied to Maritime Transport and its Implication

  • Pak, Myong-Sop;Yoon, Yu-Ri;Hong, Ran-Ju
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.48
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    • pp.57-76
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    • 2010
  • This study reviews maritime transport policy regarding liner conference and the changes in the liner market over the decades. Liner shipping industry has long been protected from competition by block exemption. To prevent excessive competition in punctual operation and its inelastic market structure, liner shipping companies formed conferences that are protected to fix the prices under the law. In the US, deregulation in transport sector began from 80's and continuing with OSRA 1998, conferences were dissolving. On the other hand, the EU with close conference system, Regulation 4056/86 contained block exemption remained in force for unlimited time without review clause. However, in Oct 2008, the EU has announced its removal, and conferences were no longer permitted to fix the price nor exchange information. Although OSRA 1998 has already broken up conferences by allowing individual service contracts, but the repeal of the immunity for price fixing will alter significantly the rule on cooperation in the industry since it is a unilateral move by the EU, especially in transatlantic lane. There are rapid changes in shipping market getting much more complicated, and with removal of 4056/86 allowing the market to be more competitive, opening up the industry with far more diverse strategic options. Hence this paper reviews on liner shipping industry and its changes of policies over the years from protected market to open competition market of today.

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Field Observation and Quasi-3D Numerical Modeling of Coastal Hydrodynamic Response to Submerged Structures

  • Yejin Hwang;Kideok Do;Inho Kim;Sungyeol Chang
    • Journal of Ocean Engineering and Technology
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    • v.37 no.2
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    • pp.68-79
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    • 2023
  • Even though submerged breakwater reduces incident wave energy, it redistributes the coastal area's wave-induced current, sediment transport, and morphological change. This study examines the coastal hydrodynamics and the morphological response of a wave-dominated beach with submerged breakwaters installed through field observation and quasi-3D numerical modeling. The pre-and post-storm bathymetry, water level, and offshore wave under storm forcing were collected in Bongpo Beach on the East coast of Korea and used to analyze the coastal hydrodynamic response. Four vertically equidistant layers were used in the numerical simulation, and the wave-induced current was examined using quasi-3D numerical modeling. The shore normal incident wave (east-northeast) generated strong cross-shore and longshore currents toward the hinterland of the submerged breakwater. However, the oblique incident wave (east-southeast) induced the southeastward longshore current and the sedimentation in the northeast area of the beach. The results suggested that the incident wave direction is a significant factor in determining the current and sediment transport patterns in the presence of the submerged breakwaters. Moreover, the quasi-3D numerical modeling is more appropriate for estimating the wave transformation, current, and sediment transport pattern in the coastal area with the submerged breakwater.