• The Journal of The Korea Institute of Intelligent Transport Systems
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• 제21권6호
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• pp.70-86
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• 2022

An autonomous demand-responsive bus with mobility-on-demand service is an innovative transport compensating for the disadvantages of an autonomous bus and a demand-responsive bus with mobility-on-demand service. However, less attention has been paid to the quantitative impact assessment of the autonomous demand-responsive bus due to the technological complexity of the autonomous demand-responsive bus. This study simulates autonomous demand-responsive bus trips by reinforcement learning on a microscopic traffic simulation to quantify the impact of the autonomous demand-responsive bus. The Chungju campus of the Korea National University of Transportation is selected as a testbed. Simulation results show that the introduction of the autonomous demand-responsive bus can reduce the wait time of passengers, average control delay, and increase the traffic speed compared to the results with fixed route bus service. This study contributes to the quantitative evaluation of the autonomous demand-responsive bus.

• Journal of Korean Society of Transportation
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• 제16권3호
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• pp.123-136
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• 1998

본 연구에서는 일반균형이론을 이용하여 버스전용차로의 효과분석모형을 정립하였 고, 이 모형을 이용하여 경부고속도로의 버스 전용차로에 대한 효과분석을 수행하였다. 본 연구에서 제안된 버스전용차로 효과분석모형에 있어 수요모형으로는 로짓 모형을 사용하였 고, 서비스모형, 즉 공급모형으로는 지체함 수식을 사용하였다. 이를 통하여 버스전용차로 설치에 따른 교통수단간 전환수요를 내생화 하였다. 경부고속도로를 대상으로 한 사례분석 의 결과, 버스전용차로의 효과를 극대화하는 혼잡수준이 존재한다는 것과, 버스전용차를 설 치할 경우 교통수단간의 수요전이효과에 따라 버스뿐만 아니라 일반 차로를 이용하는 승용 차의 통행여건도 개선된다는 사실을 발견하였다.

• Journal of Korean Society of Transportation
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• 제16권2호
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• pp.169-176
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• 1998

버스운행시격은 주어진 고정된 승객수요와 버스운행시간에 대해 최적의 버스운행시격을 결정하고, 이러한 운행시격을 요일과 시간대에 관계없이 그대로 유지하는 것이 일반적이다. 여기에 첨두시와 비첨두시의 운행시격으로 구분하여 결정하기도 한다. 그러나 실제 버스운행시간과 승객수요는 요일별 시간대별로 변화하고 이에 맞는 운행시격으로 조정하지 못함에 따라 버스운영의 비효율성을 초래하기 쉽다. 본 연구의 목적은 요일별, 시간대별로 변화하는 시내버스의 승객수요 및 버스운행 소요시간을 변수로 하여 운영자비용과 이용자비용의 합으로 본 총교통비용 모형을 수립하고, 요일별, 시간대별 최적의 버스운행시격을 구하는데 있다. 또한 최적의 버스보유대수를 구하고, 이에 따른 운행시격 조정 방법을 제안하였다. 또한 서울시에서 운행되고 있는 시내버스 노선 1개에 대한 사례연구를 통해 요일별, 시간대 별로 버스운행시격을 탄력적으로 조정함에 따라, 총교통비용을 상당히 절감할 수 있음을 입증하였고, 버스보유대수의 최적화도 유사한 결과를 나타내었다.

• Aerospace Industry
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• 제80권
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• pp.8-11
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• 2003

세계 상업용 항공기 생산의 양대 산맥을 이루는 보잉과 에어버스는 해마다 세계 항공여행 수요를 분석하고 이를 바탕으로 향후 20년을 전망하는 여객기와 화물기의 수요분석 자료를 발간하고 있다. 다음은 보잉의 Current Market Outlook 2002와 에어버스의 Global Market Forecast 2001~2002를 통해 양사의 항공기 수요전망과 시장전략을 비교해 본다.

• Journal of Korean Society for Geospatial Information Science
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• 제22권1호
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• pp.41-46
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• 2014

Bus service is easily adjusted to accommodate the changed demand. Despite the flexibility of that, its relocation should overcome the following problems: first, Bus line rearrangement should consider the balance between the demand and the supply to enhance the transit equity among the users scattered around the area that supply against demand imbalances. Second, the existing demand analysed is to crude since the demand was analysed based on TAZ. mainly based on the Dong unit. Utilization of the GWR and GIS-T data can resolve the problem. In this paper, the limitation of the conventional transit demand analysis model is overcome by deploying the GWR model which identifies the transit demand based on the geographic relation between the service location and those of the users. GWR model considers the spatial effect of the bus demand in accordance with the distance to the each bus stops using SCD(Smart Card Data) and BIS(Bus Information System). This demand map was then superimposes with the existing bus route which identified the areas where the balance between demand and supply is severly skewed. since the analysis was computed with SCD and BIS at every bus stops. the shortage and surplus of bus service of entire study area could computed. Further. based on this computational result and considering the entire bus service capacity data. Bus routes optimization from the oversupplied areas to the undersupplied area was illustrated thus this study clearly compared the benefits the GIS.

• Journal of Korean Society of Transportation
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• 제29권5호
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• pp.43-54
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• 2011

After implementing "Semi-public management system of intra-city bus", the burden of financial aid for unprofitable routes is on the increase in Busan metro city. It becomes a heavy burden on the local finance, which needs to be resolved for improving the intra-bus system. The rainfall is one of the factors influencing the demands for intra-bus in urban transportation. Motivated by this fact, this study investigates the impact of rainfall on the intra-city bus demand. Actual bus users are surveyed on their patterns and recognition of using the bus according to the amount of rainfall. A rainfall forecast model using ordered probit model is presented, and the elasticity of the intra-city bus utilization to the amount of rainfall is also analyzed. The resulting findings could be applied to promote the use of intra-city buses and also be utilized as basic data for other studies to improve the intra-city bus system.

• Journal of Korean Society of Transportation
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• 제26권5호
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• pp.81-90
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• 2008

Bus passengers need some time to adapt to the changed bus route or free bus transfer system which is part of the public transportation system restructuring plan. This research is focused on the characteristics of monthly patterns of bus passengers. The period of stabilization of bus passenger demand after the rearrangement of bus route system by a time series were analysed. In order to look into the characteristics of bus passenger demand by month, data on the number of monthly bus passengers of recent five years in metropolitan cities across the nation was collected. Kendall's coefficient of concordance is used to test whether the cities showed concordance with respect to the number of monthly bus passengers during a period of five years. The study collected and performed a time series analysis of data on the number of monthly bus passengers during the past ten years in Daegu metropolitan area which carried out a new bus route plan in February 2006. The number of monthly bus passengers in 2006 was estimated using the time series analysis. The city of Daegu found that after six months the estimated and actual values displayed a similar pattern. This result can be applied to other cities in estimating the passenger demands in the future.

• KSCE Journal of Civil and Environmental Engineering Research
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• 제28권6D호
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• pp.791-799
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• 2008

To build the system which has high utilization and usefulness for users, it is necessary to know the information type and use-demand that the use want. The purpose of this study is to forecast the preference and demand of utilization for bus information when bus information is offered through cellular phon. The accomplishments of this research are as follow : Firstly, importance on the level of individual factor and the value of change's figure can be evaluated, using preference analysis on bus information by conjoint analysis. Secondly, by establishing the use-demand model bus information using binary logit model, influence factor on whether or not the use of the user. Finally, ordered probit model was built by use behavior model in payment per call or per month of potential user of bus information. Through call times and sensitive analysis by payment methods, elasticity point, optimal payment fee, and use probability was analyzed. This study make application as basic to efficient bus information policy and to improve use rate of bus information in future because this study make it possible to get preference analysis, use-demand analysis and estimation of optimal payment fee which is reflecting various requirement in use of bus information user.

• International Journal of Highway Engineering
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• 제10권3호
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• pp.139-147
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• 2008

8 Exclusive Median Bus Lanes(EMBL) are operated in Seoul metropolitan city after the opening of Chon-ho section in 1996. But the changes in the road traffic demand on the direct and indirect influence area have not reported. In this paper, before and after survey and analysis of road traffic demand on 3 EMBLs opened in 2004 are conducted. In summary, the traffic demand of 3 EMBL road section decreased dramatically to 24.7% after the opening and then increased 1.4% after a year. The traffic demand of detour road decreased to 2.9% after the opening and then increased 0.3% after a year. Considering measurement error as ${\pm}5%$, Road traffic demands on the influence area of EMBL section are a stable state after one year. So it is presumed that the trip demand on EMBL section using vehicle does not make a detour around the influence area but divert into another transport modal.

• Aerospace Industry
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• 제53권
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• pp.30-33
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• 1997

미국의 보잉사와 록히드의 양사가 여타 항공기 제조업자를 합병 혹은 흡수하여 사실상 맘모스 기업으로 발판을 굳힘에 따라 유럽세인 에어버스를 비호하는 유럽연합측이 실질적인 시장 독점을 위한 기업연합이라고 항의하는 등 국제 항공기 시장을 놓고 항공기 제조업계의 경쟁은 갈수록 치열해지고 있다. 한편 지난 6월의 파리 에어쇼를 전후하여 보잉사와 에어버스 양사는 민간 여객기 판매에 더욱 열을 올리고 있으며 그중에도 에어버스사의 세계 시장 절반 점유계획이 크게 돋보이고 있다. 이러한 세계시장의 열띈 기운을 배경으로 항공기 수요의 장기 전망과 시장점유동향에 대하여 그 개관을 알아 보기로 한다.