• Title/Summary/Keyword: Current transport

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Studies on Sustainable Policies of European Intermodal Transport System

  • Kim, Jin-Hwan
    • Journal of Distribution Science
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    • v.9 no.2
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    • pp.25-30
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    • 2011
  • Transport is animportant sector of government regulation. Every country has its own transport policy, but European countries are evolving a common transport policy, which has a long history. The establishment of a consistent common policy in the EU's transport sector is still underway. The key motivations of this policy are 1) to establish and implement a common transport policy, 2) to clarify the concept of sustainability in the transport sector, and 3) to integrate transport services into a common infrastructure. One of the policy's objectives is the progressive movement towards sustainable development in the transport section. The EU'stransport policy has recognised that intermodality is a very important competitive tool. The EU's policy thrustin intermodal transport can be catergorised into infrastructure, technology, and standards and rules. However, obstacles to success can be detected. Cases like that of TEN-T and Marco Polo illustrate European intermodal policies in practice. As regards sustainability in the transport sector, intermodality can be an alternative solution to the increasing imbalance between transport modes and congestion arising from increased road use. Sustainability has been emphasised by the EU, which aims to establish intermodality in its future alternative transport systems while fostering sustainable development in the transport sector. Therefore, intermodality can be defined as a general trend in the current transport market, drawing interest from public institutions and transport-related market players. The EU has thus made an effort to facilitate intermodality in its territory, materialised through various policy options. Therefore, looking into the EU's intermodal transport policies is worthwhile, as doing so can provide useful lessons for all concerned parties.

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Long-Term Shoreline Change and Evaluation of Total Longshore Sediment Transport Rate on Hupo Beach (후포해빈에서 해안선의 장기변화 및 전연안표사량의 추정)

  • Park, Il-Heum;Lee, Young-Kweon
    • Journal of Ocean Engineering and Technology
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    • v.21 no.4
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    • pp.15-20
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    • 2007
  • The harbor siltation by longshore sediment transports has become a serious problem on the East Coast of Korea. A reasonable prediction of the longshore sediment rate is important to approach the siltation problem effectively. In the recently developed 1-line model, the empirical constants of the sediment transport formula, which include the absolute quantity of sediment transport rate and the spatial distribution of breaking wave height by wave deformation, are treated as calibration parameters. Since these constants should be determined by the very long-term shoreline data, the longshore sediment rates are much more reasonable values. The method was applied to Hupo Beach, which has experienced heavy siltation. The authors also discuss long-term shoreline change using aerial photos and the observed wave-induced current patterns. According to the result, the SW-direction sediment transport rate was $146,892m^3/year$, and the NE direction was $2,694,450m^3/year$ at Hupo Beach for the last 11 years. The siltation in Hupo Harbor might be affected by the NE-direction sediment transport from Hupo Beach.

A Proposal for a Classification System and Evaluation Standards for Ensuring the Safety of Transport Ventilator in Korea (국내 운반형인공호흡기 안전성 확보를 위한 분류체계 및 평가기준 제안)

  • Kim, Ji-Hyun;Cho, Sung-Ku
    • The Korean Journal of Health Service Management
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    • v.11 no.4
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    • pp.189-202
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    • 2017
  • Objectives : This study aims to present a new classification system using evaluation standards to ensure the safety of transport ventilators used in Korea. Due to the rapid advancement of technology, various types of ventilators have been developed and as the range of application increases, so does demand. With quick access to information and a growing economy, the technology used in Korean hospitals is equivalent to that of other countries; however, regulatory and safety consciousness are still lagging in Korea. Methods : Based on researching overseas cases, reference data and standards for improving the current system in Korea are proposed. Results : According to the review of transport ventilator use in Korea, it was found that concerns about safety is due to the absence of a standardized classification system for evaluating the safety and effectiveness of transport ventilators. Conclusions : In order to improve the safety of patients and the quality of medical care, it is essential to establish guidelines and assessment standards guaranteeing the safety of transport ventilators in Korea. Clear definitions and classifications for devices must precede the application of such standards. In addition, effective evaluation standards should be developed in order to resolve problems and improve upon the current system through continuous validation.

Effect of an External AC Magnetic field on Dynamic Resistance and Loss Characteristic in a Bi-2223 Tape (외부 교류자장이 Bi-2223테이프의 동저항 및 손실특성에 미치는 영향)

  • Ryu, Kyung-Woo;Choi, Byoung-Ju
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.18 no.5
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    • pp.473-477
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    • 2005
  • A Bi-2223 tape has been developed for power applications such as a fault current limiter, a power cable and a superconducting magnetic energy storage system. In such applications, the Bi-2223 tape carries time varying transport current and in addition experiences time varying external magnetic field. It is well known that the external magnetic field not only causes magnetization loss in the Bi-2223 tape, but also drastically increases transport loss due to a so-called 'dynamic resistance' We developed an evaluation setup, which can measure transport loss in external at magnetic fields. Using this equipment, we measured the dynamic resistances for various amplitudes and frequencies of an external at magnetic field perpendicular to the face in the tape. Simultaneously we investigated the effect of an external ac field on transport loss with different experimental conditions. This paper describes test results ana discussions on correlation between the dynamic resistance and the transport loss for the Bi-2223 tape.

Properties of p-n junction threshold voltage of Silicon diode by transport current in cryogenic temperature (인입 전류에 따른 실리콘(Silicon) 다이오드의 극저온 p-n 접합의 문턱 전압 특성)

  • Lee, An-Su;Lee, Seung-Je;Lee, Eung-Ro;Ko, Tea-Kuk
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.07b
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    • pp.864-867
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    • 2003
  • Since the development of semiconductors, various related research has been conducted. During research, silicon diodes have been commonly used because of their simplicity and low cost in the manufacturing process. This research deals with p-n junction threshold voltages from silicon diodes due to transport current at a cryogenic temperature. At a cryogenic temperature(77K) we could get minimum current which junction threshold voltage becomes constant. This is experimented on GPIB communication and it consist of programmable current source, multimeter which gauge the threshold voltage in a very low temperature caused by transport current from 5nA to 1mA and $LN_2$(77K) for coolant. This experiment is programmed all process using Measurement studio(Lab window) tool.

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Analysis of Current Distribution of Multi-Layer HTSC Power Cable with a Shield Layer (차폐층을 갖는 다층고온초전도 전력케이블의 전류분류 분석)

  • Lee, Jong-Hwa;Lim, Sung-Hun;Ko, Seok-Cheol;Park, Chung-Ryul;Han, Byoung-Sung;Hwang, Si-Dole
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.07a
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    • pp.535-538
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    • 2004
  • Superconducting transmission power cable is one of interesting parts in power application using high temperature superconducting wire. One of important parameters in high-temperature superconduting (HTSC) cable design is transport current distribution because it is related with current transmission capacity and AC loss. In this paper, the transport current distribution at conducting layers was investigated through the analysis of the equivalent circuit for HTSC power cable with shield layer and compared with the case of without shield layer. The transport current distribution due to the pitch lenght was improved in the case of HTSC power cable with shield layer from the analysis.

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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.

A Study on the Improvement Direction of Shipping Conference Related Domestic Laws (해운동맹 관련 국내법의 개선방향에 관한 연구)

  • You, Kwang-Hyun
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.43
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    • pp.371-393
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    • 2009
  • The biggest issue of the current international maritime transport is that EU had decided to apply the Competition Law about Shipping Conference since 2008 and UNCITRAL Convention which is the substitute of international rules related with existing maritime transport passed UN General Assembly. This movement indicates that international rules of international maritime transport are not focusing on shipping companies or forwarders anymore but consignors. According to the current circumstances, it is time for us to convert existing shipping companies and forwarders centered rules system into consignors centered international rules system as well. Thus, this study has compared and analyzed between each country's law of Shipping Conference and Korean governing law, Ocean Shipping Act.

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Effects of Electron Transport Layers on Electrical and Optical Characteristics of Blue Phosphorescent Organic Light Emitting Diodes (전자수송층이 청색 인광 OLED의 전기 및 광학적 특성에 미치는 영향)

  • Suh, Won-Gyu;Moon, Dae-Gyu
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.22 no.4
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    • pp.323-326
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    • 2009
  • We have developed blue-emitting phosphorescent organic light emitting diodes (OLEDs) using 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) and tris (8-quinolinolato)aluminum ($Alq_3$) electron transport layers. As blue dopant and host materials, bis[(4,6-di-fluorophenyl)-pyridinate-N,C2']picolinate (FIrpic) and N,N'-dicarbazolyl-3,5-benzene (mCP) were used, respectively. The driving voltage, current efficiency and emission characteristics of devices were investigated. While the driving voltage was about $1{\sim}2$ V lower in the device with an $Alq_3$ layer, the current efficiency was about 66 % higher in the device with BCP electron transport layer. the blue phosphorescent OLED with BCP layer exhibited higher purity of color, resulting from a relatively weak electroluminescence intensity at 500 nm.

An Electrical Properties of Prototype HTS Cable using Bi-2223 tape (Bi-2223 선재를 이용한 Prototype 고온 초전도 케이블의 전기적 특성)

  • Kim, Young-Seok;Lee, Byung-Sung;Jang, Hyun-Man;Kwak, Min-Hwan;Kim, Sang-Hyun
    • Proceedings of the KIEE Conference
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    • 2000.07c
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    • pp.1551-1553
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    • 2000
  • Superconducting power cable is one of the most promising energy application of high-$T_c$ superconductors (HTS). A prototype HTS cable have been constructed multi-layer cable using Bi-2223 tape and tested. The result shows that the total transport current of HTS cable in $LN_2$ was 475[A], and transport current passed through almost the outer layer (2-layer). Also, AC transport losses in outer layer of HTS cable was proportion to $I^2$ and higher than losses of inner layer. As magnetic distribution were concentrated on outer layer.

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