• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.67 no.1
• /
• pp.137-141
• /
• 2018

The voltage drop is important in electric railway for feeding a huge power of train on fixed feeding area. Nowadays it is tried to operate a high speed trains on conventional lines and there is problem on the voltage drop too. It is simulated on the conditions increased the turn ratio of trolley, installed autotransformer neutral line with variable taps. In result, it is compensated the voltage drop between ATs and better on last AT, not on the position of AT. And it is decreased a return current and neutral current of AT because of unbalance between trolley and feeder. It should be studied faster and more controllable the solid state switchs instead of the mechanical one in order to utilize this system.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2005.11a
• /
• pp.33-42
• /
• 2005

Studies on community annoyance caused by transportation noise exposure were carried out in fifty-one areas around Gimpo and Gimhae international airports, Gyungbu and Honam railway lines and east and riverside-northen motorway to accumulate social survey data and to assess the relationship between each transportation noise level and degree of annoyance in Korea. The measurements of transpotation noise were carried out using portable precision sound level meters (B&K type 2238 and LD 812) except in aircraft noise. Aircraft noise levels were measured automatically by airport noise monitoring system, B&K type 35n Social surveys were carried out to people living around noise measurement points. Questionnaires were only aggregated by face-to-face interviews using various questions concerned with demographic factors, degree of noise annoyance, interference with daily activities and health-related symptoms. The questions of noise annoyance were answered on an 11-point numerical scale. The respondents, from 18 to 70 years of age, were randomly selected and completed the questionnaire for themselves. The total number of respondents for the questionnaires was 1,839. The results showed that community annoyance of railway noise in Korea is similar to that in Japan, but is more severe than that in European countries.

• Proceedings of the KSR Conference
• /
• 2006.11b
• /
• pp.407-413
• /
• 2006

Railways are very important to get stability of railway structure as transportation system carrying a lot of passengers and freight. These days the construction of underground railway crossing such as expansion of new roads, construction of subway and gas pipe is increasing because of economic and social development. But these kinds of construction didn't take into account Cost-benefit analysis of railway which has the most important aspects of railway safety, so the results of construction didn't get a good evaluation. This study adapt Cost-benefit analysis to evaluate the economic validity of underground railway crossing. This study adjust about Cost-benefit analysis of railway part, and analyze the new method and technology of underground railway crossing constructed by Korean National Railroad and Railway Network Authority. Also this study divide between high frequency line and low frequency lineusing B/C, NPV, and IRR analysis. After analysis, B/C ratio method is the most suitable method among B/C, NPV, and IRR analysis method. Therefore this study can express economic benefit quantitatively and decrease the cost by adapting Cost-benefit analysis, and can clearly express the construction feasibility and investment effects of construction of underground railway crossing method.

• Journal of the Korean Society of Systems Engineering
• /
• v.7 no.2
• /
• pp.13-19
• /
• 2011

A LRT(Light Rail Transit) is one of the Future Urban Railway Development Project. The project's goal is to reduce a transportation congestion in the center of the city. New transportation is intensely required in order to overcome a limit of the ground transportation that is the existing public transportation, A LRT(Light Rail Transit) construction project to be based on an unmanned driving system is the large composition system that a vehicle, a signal, communication, electric, track etc. were organically integrated as echo-friendly urban transportation systems. It also put a huge budget, which is a large-scale infrastructure projects. It is international trend that Light Rail Transit projects apply a technique in System Engineering for a schedule, cost, quality elevations, and to approach in viewpoints of life-cycle from initial construction steps to operation, abolition. This paper intends to analyze RAM requirements taking into consideration ISO/IEC 15288 throughout life-cycle from concept, design, manufacture, operation and maintenance to the final phase, decommissioning, and the study seeks to suggest directions of efficient use to domestic LRT projects.

• Proceedings of the KSR Conference
• /
• 2010.06a
• /
• pp.397-407
• /
• 2010

The Railroad that is representative transportation of Low Coal and Green Growth is industry that meet and serve unspecificness many customer unexpensive price as industry doing against as social overhead capital. Present our country railroad achievement is real condition that is not coming out in eternal in the red management. Accordingly, In this research, analyze success factor of management black-ink balance of railroad advanced nation such as Japan, France and Compare with our country and grasps problem of present city railroad fare system. Finally, alleviate fare burden of customer through diversification of fare system service such as establishing point uniformly for railroad fare that introduce first in Japan JR Kyushu railroad and propose the improvement of management of railway operation organization through demand enlargement.

• Proceedings of the KSR Conference
• /
• 2007.05a
• /
• pp.1233-1238
• /
• 2007

In recently, our social is entering to service infinite competitive time., So If companys don't give satifactory and an impression customers, they don't exist. The Companies that operate railway are promoted(Seoul metro). The Korail, Seol metropolitan Rapid Transit Corperation, Incheon Rapid Transit Corporation), they are into a stronger competitor. So the service for customer is more inportant to improve the image and administration than before. Especially, station workers who work near the customer are important for cooperation image. But, there are only a few employees to operate the station like ticketing in railway station, There aren't reinforcement the service employees and expanse the utility system. especially, since the transportation card is introduced in 1996, the customers who use the T-Money card are increased. So the change of service system is necessary to provide a substantial service to customer. This paper derives the problems through analysising the operating system of station, and presents the improvement to provide substantial services to customer

• Proceedings of the KSR Conference
• /
• 2007.11a
• /
• pp.511-516
• /
• 2007

Rubber wheeled AGT(Automated Guide-way Transit) system is a prominence transportation system for urban area, because of its low construction cost and management, low noise and vibration and fine exterior view. AGT system uses concrete tracks. Concrete can be easily damaged by the impact, change of temperature and external loads. The fault of concrete track is harmful not only to riding quality but also to bridge. Therefore, in this study, the effects of railway prominence to the bridge are surveyed by experimental method. The experiment was executed for PSC bridge at AGT test line in Kyungsan. And the test results for 5mm, 10mm prominence and without prominence are compared and investigated, according to the vehicle speed.

• Proceedings of the KIEE Conference
• /
• 2001.11b
• /
• pp.333-335
• /
• 2001

In this paper, an algorithm for fault location in Auto Transformer(AT) Feeding Railway system is presented. If a fault occurs at the AT feeding circuits of electrical railway system, it is very important to find fault location and to remove it immediately for the purpose of ensuring safety for transportation. Because the characteristics of reactance-distance are not linear, only using one terminal signals to give fault distance is difficult. In this paper, first, using the KVL, 4 voltage equation are obtained. Secondly, eliminating voltage a distance equation which consists of currents at rail and line parameters including mutual effects.

• Proceedings of the KSR Conference
• /
• 2006.11b
• /
• pp.1312-1319
• /
• 2006

Several countries including Korea, Japan and European countries have reached the stage of planning, constructing their high-speed railway systems. High-speed train will become a key tool for intercity passenger transportation. Before that, safety of high-speed train must be secured. It is connected directly with track. The track is composed of ballast, tie, fastening and rail. Also, the fastening system makes tie and rail connect. In this case of the railway bridges used concrete slab track, the deflection of the bridge cause uplife of the rail at the areas between segments. In the structural analysis about it, stiffness of the fastening systems has been assumed. Therefore, use of the stiffness according to an experimental study needs. In this study, the stiffness values of various types of fastening systems are determined by the experiment and the structural behavior of fastening system is analyzed.

• Journal of the Korean Society for Railway
• /
• v.13 no.5
• /
• pp.516-520
• /
• 2010

Parametric study has been conducted to calculate the capacity of vacuum pump system that will be used to maintain the pressure of the tube structure under atmosphere level. Recently many railroad researchers pay attention to the tube train system as one of the super high speed transportation system. To achieve the super high speed, the inside of tube system should be maintained at low pressure level. In the low pressure environment, it is well known that air resistance of train is drastically decreased. Vacuum pump system will be used to make low pressure state for tube structure, exhaust the leakage air and supplement additional vacuum pumping. As results of these studies, we get the lump capacity of vacuum pump for various parameters. These results can be applied to analyze the effects of the reduction of air resistance.