• 한국가시화정보학회지
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• 제17권1호
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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.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 춘계학술대회 논문집
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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.

• 한국통신학회논문지
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• 제30권3B호
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• pp.85-94
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• 2005

본 논문은 적응형 오류제어 기법을 바탕으로 신뢰성 있는 UDP 기반의 미디어 고속 전송을 제안한다. 제안된 적응형 전송기법은 대역폭의 변화에 효과적으로 대처하기 위해서 네트워크 모니터링을 기반으로 잉여 데이터의 양을 제어한다. 수신측 피드백은 패킷 손실의 유형, 전송률 등의 수신 상황을 송신측이 인지하도록 하여 앞으로 발생될 네트워크 상황을 예측하고 이를 바탕으로 전송률과 적응형 FEC 코드 조합을 적응적으로 제어함으로써 신뢰성 있는 전송을 가능하게 한다. 제안된 시스템의 성능을 측정하기 위한 고속 네트워크에서의 전송 실험은 수백 Mbps의 전송 속도를 보이며 향상된 신뢰성을 보여준다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 춘계학술대회 논문집
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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.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 추계학술대회 논문집
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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.

• International Journal of Railway
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• 제2권1호
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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.

• 한국항만학회지
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• 제8권1호
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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.

• Membrane and Water Treatment
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• 제3권4호
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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.

• 한국철도학회지
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• 제9권2호
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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.

• 한국ITS학회 논문지
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• 제18권6호
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• pp.164-175
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• 2019

사업용 차량은 교통안전법상 난폭운전 및 사고 방지를 위해 운행기록계, 블랙박스, ADAS를 의무적으로 장착하여야 한다. 한편 도로 위 위험요소들로 인한 피해는 2013년 대비 2016년에 1.5배로 증가하고 있으며 이에 국토교통부는 도로위험정보를 수집할 수 있는 센서를 개발하고 사업용 차량에 장착하여 프로브 차량으로 활용할 수 있는 기술을 개발 중에 있다. 본 연구는 이러한 기술개발을 대비하여 주행속도에 따른 GPS 오차 편차 발생 여부를 확인하고 이벤트 지점을 통합·분리할 적정 통합 범위(m)를 도출하는 분석을 수행하였다. 그 결과 주행속도가 100km/h일 때 평균오차는 9.72m로 주행속도가 40km/h일 때 평균오차 4.69m에 비해 오차가 약 2.1배 커지는 것으로 나타났다. 이벤트 지점 적정 통합·분리 범위(m)는 주행속도와 관계없이 동일지점 인식률 90% 이상인 20m로 분석되었다. 본 연구결과는 사업용 차량이 수집할 위치기반 정보 정확도 향상 및 정책개발의 기초자료로 활용될 수 있을 것이다.