• Proceedings of the KSR Conference
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• 2011.10a
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• pp.2917-2920
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• 2011

This study aim at demonstrating the environmental performance of freight transport of the rail and road mode through an indicator of embodied energy and $CO_2$ emissions. Using the concept of LCA, the scope of evaluation includes energy production, supply chain activity and operation. The results of embodied energy and $CO_2$ emissions are normalized by means of traffic volume. The results shown that embodied $CO_2$ emissions road mode is 607.07 $gCO_2-eq./tkm$ and 284.67 $gCO_2-eq./tkm$ for road and rail mode, respectively. This number reveals that road mode is 2.1 times larger than rail mode. The results also indicate that the main contribution of $CO_2$ emission from road mode is in the operation stage, which accounts for 70%; however, it is the construction and supply chain stage that accounts for over 50% of the emission of rail mode.

• Journal of Korean Society of Transportation
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• v.31 no.3
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• pp.55-64
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• 2013

Conventionally, greenhouse gas (GHG) emissions in the transport sector have been estimated using the fuel consumption (i.e. Tier 1 method). However, the GHG emissions on road networks may not be practically estimated using the Tier 1 method because it is not practical to monitor fuel consumption on a road segment. Further, air pollutant emissions on a road may not be estimated efficiently by the Tier 1 method either due to the diverse characteristics of vehicles, such as travel speed, vehicle type, model year, fuel type, etc. Given these conditions, the goal of this study is to propose a Tier 3 level methodology to calculate $CO_2$ and $NO_X$ emissions on inter-regional roads using the information from ITS infrastructure. The methodology may avoid the under-estimation issue caused by the concavity of emission factor curves because the ITS speed or volume information is aggregated by a short time interval. The proposed methodology was applied to 4 road segments as a case study. The results show that the management of heavy vehicles' speed is important to control the $CO_2$ and $NO_X$ emissions on road networks.

• Journal of Korean Society of Transportation
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• v.20 no.7
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• pp.167-175
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• 2002

The objective of this study is to reveal a shipper's preference for road freight transport according to commodity classification code. The shipper's preference in freight transport can be obtained by using value of travel-time savings. The characteristics of freight are so various that the shipper's preference also appear widely different. In these days, there were few attempts to estimate value of freight travel-time savings in Korea. but most of them included only rail or marine freight transport so it couldn't obtain unique travel-time savings for road freight transport. In this study the value of travel-time savings of road freight transport was estimated according to commodity classification code. Revealed preference method and associated binominal logit models were applied to estimate the value of travel-time savings in transit from a Seoul metropolitan commodity flow survey data in 1998. Data sets were segmented by commodity classification code and nineteen binominal legit models were estimated according to segmented groups. The results of this study showed that the value of freight travel-time savings varied wide ranges from 16,441 won to 66,769 won per hour a vehicle along with commodity classification code.

• Safety and Health at Work
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• v.9 no.4
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• pp.454-461
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• 2018

Background: Working conditions and psychosocial work factors have acquired an important role explaining the well-being and performance of professional drivers, including those working in the field of public transport. This study aimed to examine the association between job strain and the operational performance of public transport drivers and to compare the expositions with psychosocial risk at work of three different types of transport workers: taxi drivers, city bus drivers, and interurban bus drivers. Method: A sample of 780 professional drivers was drawn from three transport companies in Bogota (Colombia). The participants answered the Job Content Questionnaire and a set of sociodemographic and driving performance questions, including age, professional driving experience, work schedules, and accidents and penalties suffered in the last 2 years. Results: Analyses showed significant associations between measures of socio-labor variables and key performance indicators such road traffic accidents and penalties. Furthermore, multiple linear regression analysis contributed to explain significantly suffered accidents from key variables of the Job Demand-Control model, essentially from job strain. In addition, throughout post-hoc analyses, significant differences were found in terms of perceived social support, job strain, and job insecurity. Conclusion: Work stress is an issue that compromises the safety of professional drivers. This research provides evidence supporting a significant effect of job strain on the professional driver's performance. Moreover, the statistically significant differences between taxi drivers, city bus drivers, and interurban bus drivers in their expositions to work-related stress suggest the need for tailored occupational safety interventions on each occupational group.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.2455-2462
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• 2008

Global warming has become one of the most important social responsibilities. After Kyoto protocol for greenhouse gas reduction by climatic change convention came into effect, developed countries are presenting various policies to reduce greenhouse gas that is produced in transport field. One of those policies is modal shift that change from road freight to sea, inland waterway and railway transportation that is eco-friendly. Because increase of road freight brings about road congestion and accident, logistics cost, air pollution and green house gases. Railways are superior to all other modes of transport in mass transportability, high speed, timeliness, safety and environmental-friendliness, but the railway industry has been pushed behind in competition. In developed country's government actively promoted relevant legislation, policies, and countermeasures known as modal shift policies to shift freight transport from road to large volume mode such as railway and ship. In this paper, we discuss the current situation in modal shift, compare it with cases in other countries EU and Japan, identify problems in Korea, and propose the following ways to enhance competitiveness of rail freight.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.9
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• pp.94-101
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• 2016

With increasing global concerns for environmental impacts, efforts have been made to encourage a modal shift from road freight to an eco-friendly transport system such as rail freight. In Korea, the government has set master plans for a green transport system but has not taken any substantial action to promote rail freight transport. In developing policies and actions to promote rail freight, quantitative studies on environmental impacts among transportation means are essential. This study examined the air pollutant emissions and greenhouse gas (GHG) emissions per unit freight transported by road and rail, respectively. To improve the accuracy, we analyzed emission data and freight transport mileage of rail freight considering diesel locomotives and electric locomotives separately. The results show that unit air pollutant emissions (except SO2) from road freight are about 7~15 times more than those from rail freight. In addition, the GHG emission unit of road freight is about 4 times higher than that of rail freight.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.8 no.5
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• pp.114-120
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• 2009

In outdoor visible light communication channels and LED road illumination communications for the intelligent transport systems (ITS), inter symbol interference (ISI) due to multipath propagation prevents high data rate transmission. Indoor wireless optical communication systems utilizing white LED lights and on the road illumination have been studying about it. Generally, plural lights are installed in room and considered to the traffic information system using existing LED traffic lights. Therefore, their optical path difference must be considered. In this paper, the influence of an optical path difference has been investigated and two approaches against this problem are introduced. One uses on-off keying, return-to-zero (OOK-RZ) coding and the other uses optical orthogonal frequency division multiplexing(OFDM).

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.1671-1676
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• 2004

This thesis watches for the present condition of both economic exchange and goods transport between South and North Korea focused on material side as a provision for the railway connection between them. This is also a predicting thesis for a smooth goods transport in case of setting up a goods transport system between south and North Korea predicting transport demand for the connection of a railway and road studying fundamental facilities and transport related laws.

• Proceedings of the KSR Conference
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• 2003.05a
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• pp.190-195
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• 2003

This thesis watches for the present condition of both economic exchange and goods transport between South and North Korea focused on material side as a provision for the railway connection between them. This is also a predicting thesis for a smooth goods transport in case of setting up a goords transport system between south and North Korea predicting transport demand for the connection of a railway and road studying fundamental facilities and transport related laws.

• 한국ITS학회:학술대회논문집
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• 2003.11a
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• pp.132-135
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• 2003