• International Journal of Naval Architecture and Ocean Engineering
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• v.4 no.4
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• pp.437-446
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• 2012

An ocean buoy energy farm is considered for Green energy generation and delivery to small towns along the Korean coast. The present study presents that the floating buoy-type energy farm appears to be sufficiently feasible for trapping more energy compared to affixed cylinder duck array. It is also seen from the numerical results that the resonated waves between spaced buoys are further trapped by floating buoy motion.Our numerical study is analyzed by a plane-wave approximation, in which evanescent mode effects are included in a modified mild-slope equation based on the scattering characteristics for a single buoy.

• International Journal of Railway
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• v.7 no.4
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• pp.109-116
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• 2014

For optimization of a low-noise track system, rail vibration and noise radiation needs to be investigated. The main influencing parameters for the noise radiation and the quantitative results of every track system can be obtained using a calculation model of generation and radiation of railway noise. This kind of model includes contact modeling and the calculation model of the dynamic properties of the wheel and the rail. This study used a nonlinear wheel/rail interaction model in the time domain to investigate the excitation of the rolling noise. Wheel/rail response is determined by time integrating Green's function of the rail together with force impulses from the wheel/rail contact. This model and the results of the study can be used for supporting calculation with the conventional model by an addition of the contributions due to nonlinearities to the roughness spectrum.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.1853-1859
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• 2008

A lot of efforts are inclined by concluding the Kyoto Protocol in Japan for the exhaust decreasing of the $CO_2$ gas in 1997. The Japan Ministry of Land, Infrastructure, Transport and Tourism is promoting various policies through various policies such as `new synthesis logistics policy', 'green logistic partnership meeting', establishment of 'logistics efficiency law' etc. The modal shift case that the individual logistic company in Japan was promoting under such a policy was analyzed in this research, and a modal shift on the distribution site was very promoted, and applicability in our country was examined through the instruction point to this in the future.

• Journal of the Korean Society for Railway
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• v.15 no.4
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• pp.388-393
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• 2012

Recently, various attempts are made to increase the efficiency of railway freight transport including bulk cement, the most important transport item of railway transport market. The major seven cement companies have started common use of private bulk cement car since April 2008 for the efficiency of railway freight transport. At that time, major seven cement companies owned 75% of whole bulk cement car. Railway companies forecasted that this project will decrease the amount of cost and transport time of freight car. With these data, it analyzed the effectiveness of the joint use of freight car on actual used data.

• International Commerce and Information Review
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• v.15 no.2
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• pp.3-23
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• 2013

In 1997, 180 countries signed the Kyoto Protocol in Kyoto, Japan. The Kyoto Protocol came into force in February 2005. The agreement calls for industrialized nations to cut greenhouse gas emissions by 5 percent from 1990 levels by 2008 to 2012. One of those polices is a modal shift that change from road freight to sea, inland waterway and railroad transportation that is eco-friendly. The increase of road freight brings road congestion, accidents, logistic costs, air pollution and greenhouse gases. Railroads are superior than the other modes of transportation in mass transportability, high speed, timeliness, safety and environmental-friendliness, but the railway industry has been pushed behind in competition. Korean railroads were used by passengers and freight transport popularly until the middle of 20th century, however, by the sudden change of logistics environments, a shaving time efficiency being most important, railroad logistic lost its competitive power against the transportation by truck. From the research which sees consequently investigated a various policy, a system and a law about Chinese logistics industry and present condition of the Chinese goods enterprise and instance analysis of the large Chinese corporation that branch out to undeveloped markets led and a Chinese logistics industry and problem point escape hereafter the heightening of competitiveness plan which is rational under prsenting boil.

• Journal of the Korean Society for Railway
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• v.20 no.2
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• pp.165-172
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• 2017

High frequency squeal noise can be generated when a railroad vehicle runs a sharp curved section; this noise causes environmental complaints and excessive wear on the wheel and the railroad track. In this paper, curved squeal noise experiments on a commercial railway were carried out to investigate this phenomenon. The relationship of the squeal noise pressure level, the frequency characteristics, the railway running speed, and the modal behavior of the wheel were investigated. At the same time, the lateral motion of the wheel relative to the rail was captured using a video camera; wheel movement was calculated when the noise was generated. queal noise occurred at the highest level at the inner front wheel; this phenomena is considered to be related to the lateral vibration response characteristics of the wheel. It can be seen that the magnitude of this squeal noise is not directly related to the increase in vehicle speed.

• Journal of Korean Society of Transportation
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• v.34 no.2
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• pp.135-145
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• 2016

This study assumes a vehicle choice model based on the multinomial model and analyzes the vehicle choice behaviors of consumer. An SP survey targeting drivers was implemented and data was collected for model estimates, with the possible choice options of the survey takers limited to gasoline, HEV, PHEV, and EV vehicles. The explanatory variable mostly displayed a significance level of under 5%, and excluding variables for price and fuel the remaining variables were all consistent with the logical direction with the plus (+) sign and the results were determined to be rational. Consumers selecting mid-size & full-size vehicles are able to afford more than consumers that selected other vehicle types, so there was relatively little consideration given to low fuel costs when compared to vehicle price. For this reason, it was determined that for the full-size vehicle model the fuel variable could be disregarded. Socio-economic variables that were statistically significant were the age and infor variables for the sub-compact & compact, the age, infor and inc3 variables for the mid-sized & full-size vehicles.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.872-880
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• 2011

In terms of accessibility and time the tram rail and bus transportation system is equipped with all the benefits of. In addition, construction and operating costs than light rail trams reduce AGT, and by car from the city center by inhibiting the transport demand management, pedestrian-oriented transportation system, including city jaebuheung can expect several effects, depending on the expected introduction of trams are. Accordingly, increasing interest in streetcars and trams, and the forum is running and the green at the National Assembly, Korea Railroad Research Institute samurai tram lines in the Korean research team developed the tram is thriving. In this study, in Korea as a way to introduce a tram tram to enhance the safety and reliability challenges for the advancement and promotion of foreign tram with the safety regulations and accident cases learn safety measures to strengthen the domestic transportation. The expected introduction of the tram fits the matter at issue and the perception of citizens and the passengers can make changes to present policies, the successful national introduction of trams and safety study aims to review.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.64 no.4
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• pp.212-219
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• 2015

Korea's first tram (so called "tram"), which was commenced the operation on May 4, 1899 of late Joseon Dynasty and run until 1968, played a pivotal role of public transportation. However, tram as new transportation mean is being recognized as traffic congestion problem becomes issue due to geometric automobile increase and reckless urban plan after stoppage of tram service. Tram has an advantage of inexpensive construction cost and eco-friendly means compared to existing and city railway, carrying more passengers rather than existing bus, excellent connectivity of existing transportation because of easy accessible to destination in the city center. Therefore, tram, what is called "Green Rvolution of Public Transportation", has a dreaming of revival and in the process of pushing. We suggest the accident type which might break out in the early stage of tram introduction and preventive measures by surveying the accident cases of tram advanced country, and study the crossing control measures.

• Korean Journal of Environment and Ecology
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• v.22 no.6
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• pp.691-706
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• 2008

This study analysed problems of railroadside buffer green space and suggested planting methods according to space function and planting concept in seashore reclaimed land, Ansan city. Planting density of railroadside buffer green zone of Ansan city was $0.04{\sim}0.17tree/m^2$, GVZ was $0.15{\sim}1.65m^3/m^2$ which is represented of deficiency of buffer function. In addition, soil hardness of mounded buffer green zone was $2.72{\sim}15kg/cm^2$. It was examined to have functions in terms of habitat for wildbirds and other organisms, surrounding landuse, urban greens, seasonality, landscape for function improvement of buffer green space. Functions of buffer green space were re-established as habitat for organism, buffer and landscape improvement, landscape and urban park, buffer zone and habitat. It was suggested to select Pinus thunbergii as a dominated species of planting method for buffer function and planting density in canopy and under-canopy layer was $0.4tree/m^2$, $0.5/m^2$ in shrub layer. In terms of landscape improvement function, Zelkova serrata, Prunus sargentii and Prunus armeniaca were selected as major species and it in canopy and under-canopy layer was $0.2tree/m^2$ and $0.5tree/m^2$ in shrub layer. In terms of habitat function Quercus acutissima, Prunus sargentii and Sorbus alnifolia were as major species and it in canopy layer was $0.06tree/m^2$, $0.1tree/m^2$ in under canopy layer, $0.8tree/m^2$ in shrub layer.