• Title/Summary/Keyword: Transport speed

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Transport of a capsule immersed in a vertical pipe (수직한 수송관 내부의 캡슐 이송)

  • Kim, Taehong;Park, Ryeol;Jeong, Joonho;Kim, Wonjung
    • Journal of the Korean Society of Visualization
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    • v.17 no.1
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    • pp.19-25
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    • 2019
  • We report a study on the dynamics of the transport of a capsule immersed in a vertical pipe. Techniques to convey objects through liquid flow pipes using a hydraulic mean are used to transport sludge and hazardous materials. For the better understanding of the techniques, we developed a theoretical model to predict the transport speed of a cylindrical capsule in a vertical pipe. The comparison of the model prediction with the experiments shows that our model using the lubrication approximation precisely describes the experimental observations in cases where the gap between the capsule and pipe wall is sufficiently small. Our study suggests parameters to control the falling speed and thus enable an accurate control of the capsule speed in hydraulic transport systems.

A Comparative Study on the Transport Policies for the Railway-centered Transport Network (철도중심교통체계로의 개편을 위한 교통정책비교분석 연구)

  • Bhang, Youn-Keun;Oh, Suk-Mun
    • Proceedings of the KSR Conference
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    • 2011.05a
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    • pp.796-811
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    • 2011
  • Authors analysized transport policies of the European countries about the intermodal transport since 2002 and urban transport to add new ones to the Korean transport policies for the railway-oriented transport network. Now the Ministry of Korean transport tries to invest more than before in the railway to increase the speed of the conventional lines and to construct high speed lines. The Ministry also try to integrate ticketing and payment of urban public transport with a smart card nationwide.

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Adaptive FEC and Rate Adaptation for High-speed Transport (고속 전송을 위한 적응형 FEC 및 전송률 제어)

  • Chang Hye young;Kim Jong won
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.3B
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    • pp.85-94
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    • 2005
  • In this paper, we propose a reliable high-speed UDP-based media transport with an adaptive error control. The proposed adaptive transport scheme controls the amount of redundancy by monitoring the network in order to adapt to network fluctuations efficiently. The feedback of receiver enables the sender to be aware of current reception status (i.e., rate and type of packet loss) and to estimate the expected network status. Based on this, the proposed transport attempts to enable reliable transport by adaptively controlling the amount of both whole sending rate and the ratio for adaptive FEC code. Experiment with high-speed network has been conducted to verify the performance of the proposed system that demonstrates the enhanced reliability of the proposed transport at the speed of up to several hundred Mbps.

High speed rail-air links : some lessons from the French case (고속철도와 항공기의 연계체계 : 프랑스 사례와 시사점)

  • 이경철;문대섭;정병현
    • Proceedings of the KSR Conference
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    • 2002.05a
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    • pp.111-115
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    • 2002
  • The TGV has been developed in a competition with the domestic air transport. But recently, with congestion, do-regulation of air transport and with the increase of number of cities served by the TGV, operators of rail and air transport are looking for a complementarity between the two modes. In this paper, we'll analyse the background and development of high-speed rail-air links in France for a development plan of high speed transportation network in a national level in Korea.

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Speed-up of the Railway Freight Services (철도화물의 고속화 방안)

  • Kim Hyun-Woong;Lee Dae-Seop;Lee Kyung-Chul;Kim Jin-Sun;Kim Kyung-Tae
    • Proceedings of the KSR Conference
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    • 2004.10a
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    • pp.1691-1694
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    • 2004
  • This paper is aiming to study of the speed-up of the railway freight services. Recently investment in freight continues to support the growth both traditional and intermodal markets, and will begin to influence newer markets. Railways offer the highest speeds in ground-based transport systems and therefore offer competitive transport times on routes between large cities. In freight transport, top speeds of 100$\∼%$150km/h are competitive with the road transport. The speed of freight railway can be increased in particular by the creation of a network of freight corridors, the speed-up of freight train, and efficient transhipment installations.

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The Use of Bituminous Subballast on Future High-Speed Lines in Spain: Structural Design and Economical Impact

  • Teixeira, P.F.;Ferreira, P.A.;Pita, A. Lopez;Casas, C.;Bachiller, A.
    • International Journal of Railway
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    • v.2 no.1
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    • pp.1-7
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    • 2009
  • The development of structural solutions for high-speed or very high-speed tracks that minimize total life cycle costs of the system is a key issue to improve the operational profitability of new investments. In opposition to conventional ballasted tracks, slab track solutions can be a cost-effective solution, but only in the cases where the benefits due to the increase in track availability and the reduction of track maintenance offsets its much higher construction costs. In the cases where such investment is not feasible, it is worth to evaluate possible structural improvements to ballasted track that allow reducing its maintenance needs without increasing too much its construction costs. This paper evaluates the design requirements and the impact of improving conventional high-speed ballasted tracks by using a bituminous subballast layer. It is divided into two main parts: first the design requirements of the structural solutions with bituminous subballast and its possible benefits on high-speed track deterioration, and secondly the evaluation of the economic impact, in terms of construction costs, of using this structural solution material in future Spanish high-speed lines.

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An Analysis of the Importance of Accessibility for High Speed Railway : Stated-Preference Approach (고속철도에 있어서 접근도의 중요성 분석에 관한 연구)

  • Park, D.R.;Nam, K.C.
    • Journal of Korean Port Research
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    • v.8 no.1
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    • pp.49-63
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    • 1994
  • The introduction of high speed railway system a significant impact on the conventional inter-urban transport systems by inducing a significant traffic from the existing modes as well as generating a new traffic. It is also closely related to intra-urban transport systems as the inter-urban traffic has its origin and destination in a city. In the context of mode choice, for high speed transport systems, it has been argued that the accessibility is the most important attribute conceived by users. Thus this study attempts to analysis the importance of the accessibility for the planned high speed railway systems particularly with respect to the location of Busan Station. For this Stated-Preference approach, which is considered appropriate for such study, is adopted, and disaggregate binary logit models for mode choice between the high speed railway and air service in Busan-Seoul corridor are developed. The elasticities for cost and service variables are also derived. The results disclose that cost is the most important which is inconsistent with most previous studies ; accessibility has considerable impact on the choice ; and frequency however has a little impacts. Concerning location of the high speed railway station the results suggest that the longer the access distance is, the more important the accessibility is. This implies that the connection of reliable access transport services such as underground are essential between the terminal and urban center.

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Recovery of Golden yellow and Cibacron LSG dyes from aqueous solution by bulk liquid membrane technique

  • Muthuraman, G;Ali, P. Jahfar
    • Membrane and Water Treatment
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    • v.3 no.4
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    • pp.243-252
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    • 2012
  • Tri-n-butyl phosphate (TBP) was used as carrier for the transport of Golden yellow and Cibacron LSG dyes through a hexane bulk liquid membrane. The transport efficiency of dyes by TBP was investigated under various experimental conditions such as pH of the feed phase (dyes solution), concentration of the receiving phase (NaOH solution), concentration of TBP in membrane, rate of stirring, effect of transport time, type of solvent, dye concentration in feed phase, effect of temperature.. The maximum transport dyes occurs at ratio of 1:1 TBP-hexane At pH 3.0 0.1 (feed phase) the transport dyes decreased. At high stirring speed (300 rpm) the dyes transport from the feed phase to the strip phase was completed within 60 minutes at $27^{\circ}C$. Under optimum conditions: Feed phase 100 mg/L dyes solution at pH 1.0 0.1, receiving phase 0.1 mol/L NaOH solution, membrane phase 1:1 TBP-hexane , Stirring speed 300 rpm and temperature $27^{\circ}C$, the proposed liquid membrane was applied to recover the textile effluent.

친환경 교통수단으로서 KTX의 역할과 기대

  • Bang Yeon-Geun
    • Journal of the Korean Society for Railway
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    • v.9 no.2 s.31
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    • pp.19-24
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    • 2006
  • Green gas emissions Trading System(ETS) came into effect in the Europe last year 2005. All transport modes have tried to reduce green gas emission and EU member countries are promoting the use of environmental friendly transport mode to avoid economic loss due to green gas emission. Besides ETS, rapidly rising of oil price and peak oil urge to invest more in the environmental friendly public transport mode and to discourage the use of private cars. The operation of KTX is estimated to bring external cost reduction up to 570 bil. won in 2004 based on European external unit costs of transport modes. This result implies that the expansion of high speed rail network and reconsideration of East-West high speed rail network which is not considered because of weak economic validity is required.

Analysis on Accuracy of GPS installed in Digital Tachograph of Commercial vehicles (사업용 차량의 프로브 활용 가능성 평가를 위한 디지털운행기록계 위치정보 정확도 분석)

  • Sim, HyeonJeong;Chae, Chandle;Kang, Minju;Lee, Jonghoon
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.18 no.6
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    • pp.164-175
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    • 2019
  • Installation of digital tachograph, black box, and ADAS have been enforced to commercial vehicles for preventing violent driving and accidents by the Traffic Safety Act in Korea. Nevertheless, the damage caused by road hazards has increased 1.5 times in 2016 compared to 2013. So, developing new technologies that can identify road hazard using the sensors installed in commercial vehicles are conducting by the Ministry of Land, Infrastructure and Transport. As a part of the technologies, this research analyze the error range of GPS installed in commercial vehicles that vary according to the driving speed. As a result, the average error was 9.72m at the driving speed of 100km/h, and the error was 2.1 times larger than the average error of 4.69m at the driving speed of 40km/h. The event point proper integration/separation range(m) was analyzed to be 20m with a recognition rate of 90% or more at the same point regardless of driving speed. The results of this research can be used as basic data for improving the accuracy of location-based data would be collected using commercial vehicles.