• 한국인터넷방송통신학회논문지
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• 제18권5호
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• pp.103-109
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• 2018

5G 목표 중 하나는 기차와 같이 고속으로 이동하는 사용자에 대해 고속의 데이터 속도를 제공하는 것이다. 따라서, High speed train (HST) 시나리오와 같은 높은 이동성 시나리오는 5세대 통신 시스템의 전형적인 시나리오가 될 것으로 예상된다. HST가 급속하게 발전함에 따라 열차 승객에게 무선 통신 데이터를 전송 해야하며, 이용자들의 요구하는 통신 속도는 점차 증가하고 있다. HST 사용자는 현재 HST 통신 시스템의 기능을 벗어나는 위치 또는 속도에 관계없이 높은 네트워크 용량과 안정적인 통신 서비스를 요구한다. 따라서, 5세대 이동통신으로 사용될 mm대역에서 5G 이동통신 시스템에 맞춰 전송 frame을 구성하고 HST 통신 시스템을 구현하고 HST 시나리오에서 광대역 비 정지 MIMO HST 채널에 대한 성능을 분석한다.

• 한국산학기술학회논문지
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• 제11권2호
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• pp.469-475
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• 2010

철도신호시스템은 열차들의 운행간격과 열차진로를 제어하는 기능을 담당함으로써 열차를 안전하고 효율적으로 운영하는 데 있어 핵심적인 역할을 수행한다. 철도신호시스템의 고장은 열차운행중지를 비롯하여 열차충돌이나 탈선등과 같은 치명적인 사고로 직결될 수 있기 때문에 시스템의 신뢰성과 안전성이 매우 중요하다. 현재까지 철도신호시스템에서는 기존의 지상신호방식이 많이 사용되어 왔으나, 지상에 설치된 신호기 현시상태를 기관사가 육안으로 확인하여 열차속도를 제어함에 따른 기관사의 인적오류 등의 사고 위험이 있다. 아울러 시스템의 수명이 다 되어 시스템절체의 필요성이 있다. 이에 따라 최근에는 컴퓨터 및 통신기술을 이용하여 열차속도제어 정보를 차량으로 송신하여 차량에서 열차속도를 제어하는 차상신호방식이 도입 및 적용되어 효과를 나타내고 있다. 수명이 다 된 신호시스템을 교체하기 위하여 승객을 위한 운행서비스를 하면서 새로운 방식으로 절체하는 것이 필요하다. 이에 본 논문에서는 열차를 운영하면서 기존의 시스템과 새로운 시스템을 혼용하여 사용하면서 절체과정의 절차와 시스템 검증을 위한 일련의 과정 중 간섭 문제에 대하여 특정한 기능을 부가하여 해결된 사례를 시험평가를 통해 검증하였다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 춘계학술대회 논문집
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• pp.1009-1013
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• 2011

Seoul Metro Line 1 to 4 guests per day to 4.5 million people have been using the subway. This is close to the city population, 57 percent of people use the subway and found that 57 percent of people use the subway and found that this is close to the city population. Motor vehicle indoor air quality, especially of the major factors affecting is passenger's clothing, cosmetics, adhesives and formaldehyde by the action and so are able to keep. Enclosure 30ppm formaldehyde during prolonged exposure at concentrations above the nose, bronchial cough and a burning can cause symptoms. It is necessary to introduce an appropriate ventilation system. 1-4 Line Press in 2008, leaving the subway, and normally the train measured in room air quality. Measurements in 2005, $19.3{\sim}83{\mu}g/m^3$, 2008 Year ND ~ $61.7{\mu}g/m^3$ is. When congestion(rush hour) to temporarily increase the formaldehyde can result in a higher number. Automatic detection of formaldehyde and improve ventilation to a practical system, and it is necessary to chatneun. In research since 2006, Removal of formaldehyde were analyzed for the study. the passengers on the effects of formaldehyde in rush hour, the plan for increasing the ventilation through the analysis of various factors, such as electric vehicle practical ways to improve air quality have been studied.

• 기술사
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• 제42권4호
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• pp.45-50
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• 2009

The modal split structure of the Korea's transportation system has been dominated by road-oriented structure. The shortage of the inftrastructure to accommodate the rapidly increasing travel demand has brought about socio-economic losses such as severe traffic congestion and high logistic costs, and thereby weakened the competitiveness of the country. Highway transportation sector is more vulnerable to energy consumption comparing with railway sector since the highway sector is dependent mostly on fossil fuels for its energy source. In 2006 annual road cogestion costs in Korea reached 24.6 trillion won, with an average annual growth rate of 5.4%. The annual road congestion cost of intercity highways were 9.2 trillion won. As the new cities that recently developed are located far from Seoul area, the boundary of commuting in Seoul metropolitan area is extended. It makes passengers have longer trips with longer travel time, and the congestion problem to be more serious. In this regards, Gyeonggi Provincial Government proposed a deeper underground metropolitan express train system for the greater Metropolitan area. which is named as GTX. Gyeonggi Province suggested 3 key underground lines, based on the outcome of the feasibility study conducted by the Korea Society of Transportation, and submitted to the Ministry of Land Transportation and Maritime Affairs for its review. If the project is approved for construction and completed in 2016, the daily volume of surface traffic bound for Seoul will be reduced substantially and therefore the users will be benefitted for time savings by an annual amount of 2 trilion won every year.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 춘계학술대회 논문집
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• pp.530-535
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• 2005

To monitor the flood level under heavy rainfall and the scour at railroad bridge, the system, which can effectively collect, store and transmit the data, is developed and applied to the field. The results in this study are as follows. 1) Monitoring for water level and scour depth is well done in view of the recording velocity and the accuracy of data which are measured. 2) This system is based on the web, internet and it is able to collect the realtime data and to analyze the risk. 3) When water level excesses the limit of danger level of a river on which railroad bridge is located, or when scour depth and angle of inclination of pier is increased, the scenario for early warning signal which sends to managers at central traffic control and drivers of trains is automatically made. It is judged that this system secures the safety of railroad and protects lives of train passengers as the warning signal sends to running train in advance at risky situation of railroad bridge under heavy rainfall.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 춘계학술대회 논문집
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• pp.947-956
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• 2005

In this paper, I scrutinize what Korea has achieved from the KTX(Korea Train Express) project for the past one year of operation since it was open to public in April 2004 while looking into some improvement measures for better services in the future. I tried to compare the clements with those of the Tokaido Shinkasen in Japan. As things may turn at its premier operation, the KTX has been suffering from a small number of passengers, low in demand. However, when I compared the previous year with the post KTX operation of one year, demand of the passenger has increased $40\%$ on Kyong-bu line. I figured the first one year of the KTX operation pretty much followed in the footstep of the Tokaido Shinkansen's. For example, the rate of the each train to be on time as the timetable was equivalent while KTX went through less technical problems than the Tokaido Shinkansen. I have come up with some ideas for improvement, which I believe will lead to the development growth of KTX. First, I suggest that we complete the construction of laying new rails on Kyong-bu line at the earliest possible time. Second, we need to extend the high speed network as well as the rail modernization. Last, I have no doubt that we should secure high technology before we forge in the overseas markets.

• 한국소음진동공학회논문집
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• 제26권1호
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• pp.97-103
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• 2016

The sensitivity of interior noise that the passengers perceive is comparatively high in the train, and structure-borne and air-borne types of noises come into the train. In this paper, to analyze contributions of these noise sources operational transfer path analysis(OTPA) is used. OTPA has some advantages of executing the contribution rates of several sources simultaneously, and in this work, 29 points are measured while running. Transfer functions between reference measurement points and response measurement points are calculated by the singular value decomposition(SVD) and Principal component analysis(PCA) method, and the frequency characteristics of the noise source are successfully derived. Also the interior noise is predicted and compared with measurement data to show the reliability.

• 한국화재소방학회논문지
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• 제22권1호
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• pp.61-67
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• 2008

본 연구에서는 화재가 발생한 전동차가 지하철 역사에 정차된 상황에서 승강장과 터널에 설치된 환기팬 작동 유무 및 전환 시간에 따른 열 및 연기 배출 특성 예측을 위하여 수치해석을 수행하였다. 환기팬 작동 방식에 따른 온도, 일산화탄소 및 가시거리 분포를 피난자의 호흡높이를 1.7m로 고려하여 비교 분석하였다. 수치해석 결과 터널 환기팬 작동으로 인하여 승강장 내의 열 및 연기가 신속히 터널부로 배출되었다. 또한 피난 진행 중에는 승강장 환기팬을 작동하고 피난이 완전히 완료된 후 터널에 설치된 환기팬을 작동하는 것이 효과적인 배연방법임을 확인할 수 있었다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집
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• pp.91-98
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• 2009

For maintaining railroad, accumulated passing tonnage is a determinant factor of appropriate rail replacement time. Recently, Seoul Metro's rail maintaining system and technology is being improved from previous years, which increasing a standard of rail replacement. Thus, this brings importance of estimating and managing for accumulated passing tonnage. In case of light weighted train such as subway, current method of calculating accumulated passing tonnage has defaults of misrepresenting accumulated passing tonnage data. Because current method is based on the weight of passengers and train., and operation data. In addition, currently there is no mechanical and electronic system that could represent and support the accurate data between heavy and non-heavy traffic area, and accumulated passing tonnage is calculated inaccurately by estimating average value each line. The current method of calculating accumulated passing tonnage misleads to unpredictable data that represent inappropriate rail replacement period, which leads to under or over analyzed replacement period. If accumulated passing tonnage is over estimated, rail replacement leads to waste of budget. Hence, it is necessary to construct reliable actual measurement system to manage rail's life safely and efficiently, and in this study the accumulated passing tonnage measurement device is installed with using rail pad of optical fiber sensors and its effect is analyzed.

• 한국철도학회:학술대회논문집
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• 한국철도학회 1998년도 창립기념 춘계학술대회 논문집
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• pp.604-611
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• 1998

High-speed railway trains entering and leaving tunnels generate finite amplitude pressure wave which propagate back and forth along the tunnels, reflecting at the open ends of the tunnels and at other discontinuities such as ventilation shafts and the train themselves. In present day railways, the magnitudes of the pressure waves are much too small to cause structual damage, but they are a serious potential source of aural discomport for passengers on unsealed trains. Almost always do the pressure waves propagating along the tunnels lead to a hazardous impulse noise near the exit portal of the tunnel. In order to alleviate such undesirable phenomena, some control strategies have been applied to the compression wave propagating inside the tunnel. The objective of the current work is to investigate the effect of tunnel entrance hoods on the entry compression wave at the vicinity of the tunnel entrance. Three types of entrance hoods were tested by the numerical method using the characteristics of method for a wide range of train speeds. The results show that the maximum pressure gradient of compression wave can be considerably reduced by the tunnel entrance hood. Desirable hood shape for reduction of the pressure transients and impulse noise was found to be of abrupt type hood with its cross-sectional area 2.5times the tunnel area.