Evaluating New Track Construction Costs of Two Different Options

Hag Lae Rho,Seong Ho Han,Gang Seog Kim 한국철도학회 2012 International Journal of Railway Vol.5 No.3

Infrastructure costs could be greatly reduced if the need for bridges and tunnels was reduced, or if the line could be shortened. Tilting trains might be a less costly alternative to building new tracks with large curve radii, because tilting trains can negotiate tighter curves without having to decrease their speeds. Tracks built for tilting trains would be cheaper, as they require fewer bridges and tunnels. This paper compares the construction costs of two different options for the new Dodam-Yeoncheong section on the Central line, which includes 148.65 km of new electrified double-track with a design speed of 250 km/h. The first option is to straighten the high-speed line. The second option is to build a line with small radii curves and run tilting trains on the line. In the first option, tunnels would account for about 51% of the new section. In comparison, the second option would have shorter curves and fewer tunnels and bridges which would reduce construction costs. Furthermore, alignment modifications could be made to several segments on the straight line, making the most of the existing roadbed. The analysis concluded that the line suited to tilting trains would be 95.7 million USD cheaper to build the straight route. That is a savings of 2.8% of the total project cost. However, this option would increase the total travel time of the route by 1.2 minutes, which means it is not necessarily the best choice.

Performance Verification of Korean Tilting-Train Experimental and Running-Time Estimation of its Imaginary Production Version on the Gyeongbu line

Hag-Lae Rho 제어로봇시스템학회 2013 제어로봇시스템학회 국제학술대회 논문집 Vol.2013 No.10

In the future, railway has to play a more important role to encounter the increasing problems within the transport sector. For attracting more traffic into the railway, it is important for railway to improve the competitiveness with other modes, especially as regards travel time or schedule speed. Korea is a mountainous country, with as much as 70% of the area is covered by hills and mountains. This geography places constraints on the minimum radius of curvature for the rail network. So it was expected that the speed of trains could be enhanced on the existing railway network without a huge investment in infrastructure by using tilting trains. Running time for tilting train is one of the most important factors, with which will be done whether the commercialization of tilting train is needed or not. In this paper, we first evaluate the performance of the Korean tilting train experimental. And then the running time and time saving of future tilting train production version will be evaluated compared with 2012’s conventional trains and non-tilting trains, based on the Gyeongbu line. The running time for the tilting train on the Gyeongbu line (Seoul~Busan) is 4 hours 20 minutes, which is 31 minutes shorter than that of conventional train journey, which took 4 hours 51minutes. This decrease is separated into two effects. 14 minutes, 45%, of the total time saving is due to the enhanced dynamic capabilities of a train, which results from the diesel-powered trains to EMU trains. But on the other hand, the time saving benefit with tilting device is beyond 55% - 17 minutes - from reduced total running time.

Study on the Calculation of Safe Sidetracking Time for the Local Train using Blocking Time Model

Hag Lae Rho,Yu Duck Won,Kyu Hyoung Choi,Gang Seog Kim 한국도시철도학회 2015 IJAR Vol.3 No.3

It is increasing interested in the introduction of an express train to enhance the competitiveness of the railway. If the express train would be introduced in a certain line on which only local trains run, sidetrack is needed for the express train to overtake local train. In addition, it is also very important to properly set the sidetracking time of local train in terms of ensuring safety of rail traffic flows. This paper explains the calculation method of safety sidetracking time for the local train on the shunting station using the blocking rime model. And then, a case study shows the operation of the mixed train traffic using overnight-staying track of SMRT Line 6. It includes the estimation of safety sidetracking time for local train and the possible operation plan for the conflict-free local & express traffic flows.

경부선 틸팅열차의 가능 운전시간 추정 연구

노학래(Hag-Lae Rho),한성호(Seong-Ho Han) 대한전기학회 2015 전기학회논문지 P Vol.64 No.4

A rising attention is paid to the railway system in many countries. KOREA is also of the opinion that the railway has to play a more important role in the near future to face up to the problems that increase gradually in the transport sector. To attract more traffic to the rail networks, it is important for rail modes to have running time competitiveness. Tilting trains, where it is possible to tilt the car-body towards the center of the curve, are a less expensive alternative to shorten travelling times on existing lines. Running time for tilting train is one of the most important factors, with which passenger demand forecasting or economic feasibility analysis will be done. This paper evaluates the speed limitation of tilting train around curves and also presents calculation process of its simulated possible running time. Then the adequacy of estimated time is verified with running time for Korean protype tilting train TTX (Tilting Train eXpress) by actual test run. As a case study, the estimated running time for the production version of tilting train and its time saving are presented compared with 2012’s conventional Saemaul trains and non-tilting trains on the Gyeongbu line in the Korean rail network.

On an Injective System for Normed Algebras

Rhee,Hag Lae 漢陽大學校 1974 論文集 Vol.8 No.-

이 글에서는 ??가 單位를 가지은 R 環의 單射系이고, Unitary環의 準同型寫像이라고 할 때 環으로서 單射極限 B는 φ??로 極限準同形寫像族으로 한 λφ??를 定義함으로써 R 環으로 되는 것에 對해서 적었고, B??가 單位를 가지는 實數위에서 Norm 環이고 φ??가 Norm 保存埋藏인 單射系(B?? ??에 처해서 적었으며, 單射極限 B와 極限準同 形寫像φ??를 가지는 單射系??에 對해서 적었다. ??가 完全하면 ??에 對한 逆 Element의 集合??는 開이고 ??에 對한 極大 Ideal은 閉되어 있는 것에 對해서 펼쳤고, 完全한 正規 Hausdorff 位相空間의 Filter 基底에서 定義된 有界 實數連續函數에 對한 環의 直系에 對하여 펼쳤다. 이 글에서는 單位를 가지는 實數위에서 Norm 多元環의 單射系에 對한 特殊型을 연구하였다.

완 · 급행열차 혼합운행에 따른 부본선 설치 정거장 검토 (At which station would be installed subsidiary-main track? - Problems of interference with mixed traffic on the railway)

노학래(Hag-Lae Rho) 한국철도학회 2011 한국철도학회 학술발표대회논문집 Vol.2011 No.5

A subsidiary-main track for passenger station is a low-speed track section distinct from a through route such as a main track. It is parallel to a through track and connected to it at both ends by switches. Sidetracks allow for fast, high priority trains to pass slower or lower priority trains going the same direction. They are important for efficiency to order and organize the flow of rail traffic. In this paper we first describe the minimum headway between trains using the concept of occupation time in a block section, which depends on block systems, signalling system and safety technology. And then a stepwise approach is presented to select station, which is suitable to install sidetrack for a given train-traffic pattern. This approach is tested with sample example data, which are surveyed from track geometry based on the to-be-constructed line.

틸팅열차 중앙선, 태백/영동선 투입에 따른 운행시간 단축효과 검토

노학래(Hag-Lae Rho) 한국철도학회 2010 한국철도학회 세미나자료 Vol.2010 No.10

It is expected that the 1<SUP>st</SUP> commercial service of tilting-train will be launched on the 194 ㎞ Jungang-line between Cheongnyangni and Youngju at the end of 2013. In this paper, competition with express bus is evaluated as regards travelling time. Travelling times will be reduced 47% from 3:33 (in 2009) to 1:53 (in 2016). It should be pointed out that competitive power for tilting-train will be increased mainly due to the following factors; (a) reduction in the travelling times due to the tilting devices and increased top-speed, (b) more train departure due to running time reduction, (c) higher service quality and (d) a customers’ better image to tilting-train as a new product. We hope the railway will become the market leader in the future and attain profitability from the viewpoint of both business as well as national economics after introducing tilting-train services at 2013 in KOREA.

시뮬레이션 기반 철도 선로용량의 최적 활용범위 설정

노학래(Hag Lae Rho) 한국도시철도학회 2020 한국도시철도학회논문집 Vol.8 No.2

철도운영에서는 철도 인프라의 활용도를 최대화하면서 동시에 열차 간 간섭에 의한 운영품질 저하를 최소화할 수 있는 용량 활용의 적정 범위를 결정하여야 한다. 이를 위해서는 해당 인프라의 최대용량과 열차 교통량에 따른 대기시간 함수가 필요하다. 본 논문에서는 열차시각표 시뮬레이션을 통하여 얻은 열차당 평균 대기시간과 최대용량 자료를 이용하여 대기시간 함수의 파라미터를 추정하였다. 이 대기시간 함수식을 기반으로 대기시간의 상대적 최소 민감도와 평균 정규화 트래픽의 최대 성능을 나타내는 철도 선로용량 이용률의 상‧하한을 도출하였다. 따라서 철도 인프라의 적정이용률은 이와 같은 상‧하한 사이에서 결정되어야 할 것이다. 본 논문에서 제시하는 시뮬레이션 실험기반의 최적 용량 활용범위 설정 방법은 복잡한 역 구내 선로 또는 네트워크 구조의 철도 노선용량분석에 활용 가능할 것으로 기대되며, 이는 철도 인프라의 추가 투자수요를 파악하는 데에도 도움이 될 것이다. Railway operation deals with determining optimal degree of capacity utilization for given infrastructure. This is to fully use railway infrastructure and to minimize the decreasing operation quality which is caused by conflicts between trains. For this, we need a maximum capacity for given infrastructure and a waiting time function on train traffic. In this paper, the parameters of waiting time function are estimated using average waiting time per train and maximum capacity obtained from timetable simulation. Based on this waiting time function, the lower and upper bounds of capacity utilization rate are derived, which show minimum relative sensitivity of waiting time and maximum average normalized traffic performance, respectively. Therefore, the reasonable capacity utilization rate of railway infrastructure should be decided between these lower and upper limits. Simulation-based estimation for optimal capacity utilization range in this paper could be used to determine the utilization of existing infrastructure including large stations with complicated track-layout and railway lines with network structure, which will help us to identify additional investment needs for rail infrastructure.

일반 EMU열차와 틸팅 EMU열차의 운전시간 비교 : 중앙선 청량리~영주 구간

노학래(Hag-Lae Rho) 한국철도학회 2011 한국철도학회 학술발표대회논문집 Vol.2011 No.10

Korea is a mountainous country, with as much as 70% of the area is covered by hills and mountains. This geography places constraints on the minimum radius of curvature for the rail network. It was expected that the speed of trains could be enhanced on the existing railway network without a huge investment in infrastructure by using tilting trains. The development of tilting trains in Korea started in 2001 as research & development project. A 6-car prototype test tilting train, called the Tilting Train eXpress (TTX), was built in December 2006 and experimental trials began in 2007. TTX has distributed power, is designed to run at 200 km/h, and has a planned service speed of 180 km/h. In this paper, we first describe the performance of tilting train, and then present the estimated running times, and the time saving compared with today's conventional trains and non-tilting trains, based on the Jungang line. So the time saving could be separated into two effects by higher track top-speed and tilting devices.

Evaluating New Track Construction Costs of Two Different Options: Conventional Trains vs. Tilting Trains

Rho, Hag Lae,Han, Seong Ho,Kim, Gang Seog The Korean Society for Railway 2012 International Journal of Railway Vol.5 No.3

Infrastructure costs could be greatly reduced if the need for bridges and tunnels was reduced, or if the line could be shortened. Tilting trains might be a less costly alternative to building new tracks with large curve radii, because tilting trains can negotiate tighter curves without having to decrease their speeds. Tracks built for tilting trains would be cheaper, as they require fewer bridges and tunnels. This paper compares the construction costs of two different options for the new Dodam-Yeoncheong section on the Central line, which includes 148.65 km of new electrified double-track with a design speed of 250 km/h. The first option is to straighten the high-speed line. The second option is to build a line with small radii curves and run tilting trains on the line. In the first option, tunnels would account for about 51% of the new section. In comparison, the second option would have shorter curves and fewer tunnels and bridges which would reduce construction costs. Furthermore, alignment modifications could be made to several segments on the straight line, making the most of the existing roadbed. The analysis concluded that the line suited to tilting trains would be 95.7 million USD cheaper to build the straight route. That is a savings of 2.8% of the total project cost. However, this option would increase the total travel time of the route by 1.2 minutes, which means it is not necessarily the best choice.