• Title/Summary/Keyword: high-speed transport

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A Study on Loading/Unloading Methods for High-Speed Container Loading/Unloading System (고속 컨테이너 하역시스템의 하역방법에 관한 연구)

  • 박경택;김선호;김두형
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 1998.10a
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    • pp.167-174
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    • 1998
  • Recently several researches of high speed container ship and loading system are mainly accomplished in U.S.A. and Japan. Its shipping service is not realized but it is realized in near future. To effective use of the feature and efficiency of them, quay, loading/unloading. yard operation system, port management system and connection transport system must be well integrated and operated. Specially, loading /unloading speed of container crane is important for making effective use of them. To speed up loading/unloading system, RO-RO and LO-LO methods that are mostly exclusive system are studied on the container crane with special structure and mechanism to handle individual container or bundle of containers. In this paper these methods are shown. When new high speed loading system of container is desighed, the realistic constrains must be considered.

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Analysis of Meteorological Characteristics related to Changes in Atmospheric Environment on Jeju Island during 2010-2012 (최근(2010~2012년) 제주지역 대기환경 변화에 관한 기상특성 분석)

  • Song, Sang-Keun;Han, Seung-Bum;Kim, Suk-Woo
    • Journal of Environmental Science International
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    • v.23 no.11
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    • pp.1889-1907
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    • 2014
  • The characteristics of meteorological conditions related to changes in atmospheric environment on Jeju Island were investigated during recent years (2010-2012). This analysis was performed using the hourly observed data of meteorological variables (air temperature, wind speed and direction) and air pollutants ($O_3$, $PM_{10}$, $SO_2$, $NO_2$, and CO). Out of 5 pollutants, $O_3$ and $PM_{10}$ concentrations have frequently exceeded national environmental standards in the study area during the study period, with relatively higher concentrations than the others. The concentrations of $O_3$ and $PM_{10}$ in 2010 and 2011 were somewhat higher than those in 2012, and their highest concentrations were mostly observed in spring followed by fall. Nighttime $O_3$ concentrations (with relatively high concentration levels) were almost similar to its daytime concentrations, due to less $O_3$ titration by very low NO concentrations in the target area and in part to $O_3$ increase resulting from atmospheric transport processes. The transport effect related to the concentration variations of $O_3$ and $PM_{10}$ was also clarified in correlation between these pollutants and meteorological variables, e.g. the high exceedance frequency of concentration criteria with strong wind speed and the high concentrations with the westerly/northwesterly winds (e.g., transport from the polluted regions of China). The overall results of this study suggest that the changes in atmospheric environment in the study area were likely to be caused by the transport effect (horizontal and vertical) due to the meteorological conditions rather than the contribution of local emission sources.

Analysis of loading capacity of Korean High-Speed Train by using MAS(Moving Autoblock System) method (MAS(Moving Autoblock System) 방법을 이용한 한국형 고속전철의 선로 효율 분석)

  • Jeong, P.G.;Lee, J.D.;Lee, J.H.;Cho, C.H.;Kim, K.H.;Kim, Y.J.
    • Proceedings of the KIEE Conference
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    • 2000.07b
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    • pp.1426-1428
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    • 2000
  • A new block system - MAS (Moving Autoblock System) whose efficiency is higher than FAS(Fixed Autoblock System) in the loading capacity is required to accomodate the increasing transport volume. That MAS has higher efficiency has already been verified through various studies, especially in a line with different types of travelling trains. The efficiency of MAS for Korean high speed line with two different train model is analyzed by computer simulation. The results show that MAS is more efficient than FAS in the loading capacity.

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A Simulation-Based Study of FAST TCP Compared to SCTP: Towards Multihoming Implementation Using FAST TCP

  • Arshad, Mohammad Junaid;Saleem, Mohammad
    • Journal of Communications and Networks
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    • v.12 no.3
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    • pp.275-284
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    • 2010
  • The current multihome-aware protocols (like stream control transmission protocol (SCTP) or parallel TCP for concurrent multipath data transfer (CMT) are not designed for high-capacity and large-latency networks; they often have performance problems transferring large data files over shared long-distance wide area networks. It has been shown that SCTP-CMT is more sensitive to receive buffer (rbuf) constraints, and this rbuf-blocking problem causes considerable throughput loss when multiple paths are used simultaneously. In this research paper, we demonstrate the weakness of SCTP-CMT rbuf constraints, and we then identify that rbuf-blocking problem in SCTP multihoming is mostly due to its loss-based nature for detecting network congestion. We present a simulation-based performance comparison of FAST TCP versus SCTP in high-speed networks for solving a number of throughput issues. This work proposes an end-to-end transport layer protocol (i.e., FAST TCP multihoming as a reliable, delaybased, multihome-aware, and selective ACK-based transport protocol), which can transfer data between a multihomed source and destination hosts through multiple paths simultaneously. Through extensive ns-2 simulations, we show that FAST TCP multihoming achieves the desired goals under a variety of network conditions. The experimental results and survey presented in this research also provide an insight on design decisions for the future high-speed multihomed transport layer protocols.

Web Tension Control Using Output Feedback

  • Oh, Seung-Rohk
    • Journal of IKEEE
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    • v.11 no.4
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    • pp.213-218
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    • 2007
  • We consider a web transport system. The objective of this paper is to design the output feedback controller such that the controller can track a desired tension and processing speed on web transport system. We propose the new design method using observer and feedback linearization technique. The proposed method use a nonlinear feedback to transform to linear system and high gain observer to estimate the state value. We show that the proposed controller can achieve the control object using only output. We show a performance of controller via the simulation.

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HYBRID LIGHT DUTY VEHICLES EVALUATION PROGRAM

  • Trigui, R.;Badin, F.;Jeanneret, B.;Harel, F.;Coquery, G.;Lallemand, R.;Ousten, JP.;Castagne, M.;Debest, M.;Gittard, E.;Vangraefshepe, F.;Morel, V.;Baghli, L.;Rezzoug, A.;Labbe, J.;Biscalia, S.
    • International Journal of Automotive Technology
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    • v.4 no.2
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    • pp.65-75
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    • 2003
  • A HEV evaluation program, funded by ADEME, was carried out by a group of Laboratories of different specialties in order to evaluate and compare consumption, emission and component technologies of the three first HEVs put on the market (Toyota Prius, Nissan Tino and Honda Insight). This paper presents the results obtained until now. These results show good consumption and emission performance of the tested vehicles compared to conventional ones. The energy management seems to be globally the same for the three vehicles excepting for cold stans where the Insight allows a very earlier stop of the engine compared to the Tino and especially to the Prius. A mapping of the engine consumption of the Prius and the Insight was performed in order to furnish data for the simulation models. The Permanent Magnet motors of the Prius and Tino have different number of pair poles and then different emf at a given speed. The low emf values of the Prius allow operation at high speed with less field weakening control than for the Tino. The inverters of the Prius and the Tino, controlled by a PWM at respectively 5 kHz and 7 kHz switching frequency, are made of IGBTs with high commutation performances.

Characteristics of East Asia Synoptic Meteorological Conditions in Association with Haze phenomena (연무와 연관된 동아시아의 종관기상 특성)

  • Jo, Hyun-Young;Kim, Cheol-Hee
    • Atmosphere
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    • v.20 no.2
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    • pp.161-172
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    • 2010
  • In an effort to investigate the characteristics of synoptic meteorological conditions in association with long-range transport of haze phenomena occurred over Korea, we statistically classified characteristics of haze events into two types of haze: stagnant case and long-range transport case, based on the synoptic meteorological parameters, and analyze comparatively the characteristics of synoptic meteorological conditions for each case. The results showed that the occurrence frequency of stagnant case accounts for 64.5%, showing superiority of stagnant haze cases over the long-range transport case which occupies only 35.5% among total 67 cases for the period from 2000 to 2007. This result indicates that haze phenomena occurred over Korea has influenced by not only the emission in Korea by itself but long range transport effects originating from China inland. The synoptic condition on 850hPa level showed that, when stagnant case occurred, Korean peninsula was located under the effects of negative vorticity with the significantly weak wind speed and stable atmospheric condition. In contrast, long-range transport case shows positive vorticity and relatively strong wind speed over 850hPa level, especially with the location of high pressure system over the area of southwestern China. This location of high pressure system implies to induce the westerlies or northwesteries consistently due to its pressure gradient by itself. Also other comparative studies haze days (vs.) Asian dust days are carried out, and we found out that the patterns of long-range transport of haze phenomena in Korea shows similar to Asian dust case but the static stability condition indicates more stabilized atmospheric condition than dust phenomena.

BI-DIRECTIONAL TRANSPORT AND NETWORKED DISPLAY INTERFACE OF UNCOMPRESSED HD VIDEO

  • Park, Jong-Churl;Jo, Jin-Yong;Goo, Bon-Cheol;Kim, Jong-Won
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2009.01a
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    • pp.184-188
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    • 2009
  • To interactively share High Definition (HD)-quality visualization over emerging ultra-high-speed network infrastructure, several lossless and low-delay real-time media (i.e., uncompressed HD video and audio) transport systems are being designed and prototyped. However, most of them still rely on expensive hardware components. As an effort to reduce the building cost of system, in this paper, we propose the integration of both transmitter and receiver machines into a single bi-directional transport system. After detailed bottleneck analysis and subsequent refinements of embedded software components, the proposed integration can provide Real-time Transport Protocol (RTP)-based bi-directional transport of uncompressed HD video and audio from a single machine. We also explain how to interface the Gbps-bandwidth display output of uncompressed HD media system to the networked tiled display of 10240 $\times$ 3200 super-high-resolution. Finally, to verify the feasibility of proposed integration, several prototype systems are built and evaluated by operating them in several different experiment scenarios.

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The Feasibility Study of the Scenario of 400kph Maximum Speed Test in HEMU (High-speed Electric Multiple Unit) System (400km/h급 전차선로 시스템의 시범적용 구간선정 연구)

  • Ryoo, Hyang-Bok;Jang, Sa-Sool;Park, Jae-Woong;Lee, Hae-Won
    • Proceedings of the KSR Conference
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    • 2011.10a
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    • pp.761-767
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    • 2011
  • Since the "Low Carbon, Green Growth" as a social requirements is attracted public attention, the policies and investments of the railway which have been less estimated than road is re-considered. Since the starting the commercial service (2004. April), the KTX have been operated successfully while transport passengers over 100million for years. And also the project for development of KHST (Korea High Speed Train ; G7) had been accomplished with a good result, the first trainset of KTX-II which base on G7 project was manufactured and testing now. On the other hand, the world's technology of the high speed train is more faster, and changing to a distributed traction system. To catch up the world's leading technology, the HEMU(High-speed Electric Multiple Unit) project will secure new technology and aims to promote the technology of domestic high-speed train. The authors indicates the result of detail review such as a curve, slope of the track and electrical dead section of the catenary to test at 400kph and also the performance simulation of the developed rolling stock in this paper. As the result, the authors devise the test scenario to perform a maximum speed test (stability at max. speed, acceleration & deceleration etc) with the restricted conditions such as track length, track available time etc by considering above result.

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