• Proceedings of the KSR Conference
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• 2010.06a
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• pp.1159-1165
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• 2010

This paper describes an energy efficient train control. In these days, the researchers develop the energy efficient railway technologies, such as energy storage system, energy efficient driving. Mass rapid transit (MRT) railways, which are an important means of public transportation in urban areas, have operational characteristics that include short headways, frequent departures and arrivals. Therefore, when multiple trains are operating in the same power supply system, it is important to synchronize the energy tractions and regenerations. This paper define the group of trains for energy saving according to a power supply. We analyze the current synchronized driving situations and estimate the effect.

• Journal of the Korean Society for Railway
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• v.6 no.3
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• pp.169-173
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• 2003

Transportation by railroad is superior to other transport in a mass transport, stability, rapid transit, delightfulness and low-pollution etc. But, it need to ensure a track stability that supports the train-load for high-speed in transportation by railroad. Ballast resistance force resists against the buckling of track taking a rail-tie's place. So, it plays an important role in a careful train-service. So, in this papers, we forced on measuring and theorizing about the Ballast Resistance Force that play a key role in track stability and high-speed. And we studied the mechanical property. Finally, we suggested the method of securing Ballast Resistance Force and the report for a careful train-service in high-speed.

• Journal of Microbiology and Biotechnology
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• v.15 no.5
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• pp.1094-1099
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• 2005

Photosynthetic dinoflagellates contain a water-soluble, light-harvesting antenna called the peridinin-chlorophyll-protein (PCP) complex, which has an apoprotein with no sequence similarity to other known proteins. There are two forms of PCP apoproteins; the 15-kDa short form and the 32- to 35­kDa long form. The present study describes the PCP protein and its cDNA from Alexandrium tamarense. A cDNA library was constructed from mRNA isolated from A. tamarense. The complete PCP cDNA was generated by reverse-transcription coupled to polymerase chain reaction (RT-PCR), together with rapid-amplification of cDNA ends (RACE). The A. tamarense PCP cDNA encoded a 55-amino acid signal peptide and a 313-amino acid mature protein with a calculated mass of 32 kDa, which corresponded to that of the long form of PCP. Phylogenetic analysis indicated that the sequence of A. tamarense PCP did not cluster with the short-form PCPs, to which it was only about $55\%$ identical, but which were $79-83\%$ identical to other long-form PCPs. The deduced amino acid sequence of A. tamarense PCP contains an internal duplication, which suggests the possibility that long-form PCPs arose by gene duplication or by the fusion of genes encoding the short form. The abundance of PCP mRNA changed substantially in response to different light conditions, indicating the possible existence of a photo-acclimation response in A. tamarense.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.24 no.5
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• pp.399-408
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• 2006

Railroads have been developed as public transportation and made a great contribution to national economic growth. But after the mid-20th century, its qualities have been getting low because of focusing on the investment and development of cars and airplanes. Its role which is getting the excellent merits on the mass transportation, rapid transit, safety, state period, energy efficiency, and prevention of environmental pollution has been reconsidered. Elements of horizontal alignment are needed in the case where the existing railroad lines should be improved or moved. If its design drawing was lost or damaged, it is impossible to recover. It is not easy to repair for it as disasters. We must understand an existing railroad line to bring a function included a basic geography situation. In this study, we acquire, analyze, and process the digital images of the railroad and then reappear shape of three dimension. And we expect to be utilized to construct the facility information by extracting the alignment elements of existing railroad lines reversely.

• Journal of the Korean Society for Railway
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• v.14 no.2
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• pp.167-173
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• 2011

This paper considers the problem of revising train departure time to reduce electric power consumption of mass rapid transit (MRT) railways. The motion of a train running between stations is divided into three phases: traction, coasting, and deceleration phases. The traction phase requires high electric power to operate MRT railways. In the coasting phase, the train moves stably by consuming little or no power. The deceleration phase is a braking mode and produces some electric power called regenerated brake power owing to inertia force for the train generated In the traction and coasting phases. The regenerative energy can be used by other accelerating trains within a specific range from the train and thereby the power consumptions of train can be reduced. We developed a mixed integer programming model to solve the problem. To validate the suggested model, a computational experiment was conducted using real data from Korea Metropolitan Subway.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.20 no.5
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• pp.1-17
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• 2021

Identifying the exact train and the type of train boarded by passengers is practically cumbersome. Previous studies identified the trains boarded by each passenger by matching the Automated Fare Collection (AFC) data and the train schedule diagram. However, this approach has been shown to be inefficient as the exact train boarded by a considerable number of passengers cannot be accurately determined. In this study, we demonstrate that the AFC data - diagram matching technique could not estimate 28% of the train type selected by passengers using the Seoul Metro line no.9. To obtain more accurate results, this paper developed a two-step method for estimating the train type boarded by passengers by applying the AFC data - diagram matching method followed by a mixture distribution analysis. As a result of the analysis, we derived reasonable express train use/non-use passenger classification points based on 298 origin-destination pairs that satisfied the verification criteria of this study.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.9 no.2
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• pp.43-54
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• 1989

In this paper, measured and calculated responses are compared in order to give how the static and dynamic responses occurred in steel railway bridges due to train loads could be calculated appropriately. From this, it is investigated how the impact factors are varied by changing the train speed above 100km/h Field measurement is carried out by the steel strain gages and displacement transducers at the main design points, and then the static and dynamic response, fundamental frequencies, damping ratios and impact factors of the bridges are obtained. Static analysis is done using the computer program developed according to three dimensional matrix structural analysis in which the trains and bridges are modelled as 1,2 and 3 dimensions. Dynamic analysis is done according to 2 approaches, the moving force and mass problem. In moving force problem, the solutions are obtained by the modesuperposition-method and in moving mass problem by the direct integration method. From this study, it is known that in order to obtain the static response in the railway bridges, the bridge could be modelled by 1 or 2 dimension as in the highway bridge, however the response ratio(measured/calculaled) is high comparing to the highway bridges. By the way, the dynamic response should be obtained by the moving mass problem. And by comparing the measured and code specified impact factors, it is known that the factors specified in the present railway bridge code are very safe under the present service speed below 100km/h. However, because the factors become very high under the speed above 100km/h, especially in the simple plate girder bridge, it is thought that the code specification on impact factor should be discussed enough under the rapid transit system.

• Journal of Korean Society for Atmospheric Environment
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• v.32 no.2
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• pp.216-232
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• 2016

In present, the Seoul City is undergoing traffic congestion problems caused by rapid urbanization and population growth. Thus the City government has reorganized the mass transportation system since 2004 and the subway has become a very important means for public transit. Since the subway system is typically a closed environment, the indoor air quality issues have often raised by the public. Especially since a huge amount of PM (particulate matter) is emitted from ground tunnels passing through the subway train, it is now necessary to assess the characteristics and behaviors of fine PM inside the tunnel. In this study, the concentration patterns of $PM_1$, $PM_{2.5}$, and $PM_{10}$ in the Seoul subway line-2 were analyzed by real-time measurement during winter (Jan 13, 2015) and summer (Aug 7, 2015). The line-2 consisting of 51 stations is the most busy circular line in Seoul having the railway of 60.2 km length. The the one-day average $PM_{10}$ concentrations were $148{\mu}g/m^3$ in winter and $66.3{\mu}g/m^3$ in summer and $PM_{2.5}$ concentrations were $118{\mu}g/m^3$ and $58.5{\mu}g/m^3$, respectively. The $PM_{2.5}/PM_{10}$ ratio in the underground tunnel was lower than the outdoor ratio and also the ratio in summer is higher than in winter. Further the study examined structural types of underground subsections to explain the patterns of elevated PM concentrations in the line-2. The subsections showing high PM concentration have longer track, shorter curvature radius, and farther from the outdoor stations. We also estimated the outdoor PM concentrations near each station by a spatial statistical analysis using the $PM_{10}$ data obtained from the 40 Seoul Monitoring Sites, and further we calculated $PM_{2.5}/PM_{10}$ and $PM_1/PM_{10}$ mass ratios near the outdoor subway stations by using our observed outdoor $PM_1$, $PM_{2.5}$, and $PM_{10}$ data. Finally, we could develop pollution maps for outdoor $PM_1$ and $PM_{2.5}$ near the line-2 by using the kriging method in spatial analysis. This methodology may help to utilize existing $PM_{10}$ database when managing and control fine particle problems in Korea.