• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.3 no.1 s.4
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• pp.45-52
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• 2004

There are many cities installing ITS(Intelligent Transportation Systems) and running TMC(Trafnc Management Center) to improve mobility and safety of roadway transportation by providing roadway information to drivers. There are many devices in ITS which collect real-time traffic data. We can obtain many valuable traffic data from the devices. But it's impossible to avoid missing traffic data for many reasons such as roadway condition, adversary weather, communication shutdown and problems of the devices itself. We couldn't do any secondary process such as travel time forecasting and other transportation related research due to the missing data. If we use the traffic data to produce AADT and DHV, essential data in roadway planning and design, We might get skewed data that could make big loss. Therefore, He study have explored some imputation techniques such as heuristic methods, regression model, EM algorithm and time-series analysis for the missing traffic volume data using some evaluating indices such as MAPE, RMSE, and Inequality coefficient. We could get the best result from time-series model generating 5.0$\%$, 0.03 and 110 as MAPE, Inequality coefficient and RMSE, respectively. Other techniques produce a little different results, but the results were very encouraging.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.9 no.2
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• pp.12-22
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• 2010

The variable message sign(VMS) is a facility to smoothen traffic flows and enable safe passing by providing real-time necessary information on roads, weather, transportation, and traffic regulations. The VMS also solves a feeling of uneasiness and gives a sense of psychological security by providing information to drivers. However, the VMS has a strong character of being a non-market product but a public product, so it has not normally been evaluated for its value. This research has evaluated a value of satisfaction level for traffic information users, using a contingent valuation method(CVM). As a result of evaluating the value of satisfaction level for users through division into an urban roadway and an urban highway for the cities where an intelligent transportation system(ITS) has been established, the urban highway had a value of 96.7 won/system and the urban roadway had a value of 76.3 won/system.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.16 no.1
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• pp.1-13
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• 2017

A national highway takes on an arterial roadway role between regions. It's traffic volume of minor approach is very lower than mainline because most of the traffic of national highway consists of through traffic. This means an actuated signal operation is more efficient on the national highway than pre-timed signal. actuated signals have detections on some or all movements except the mainline. In spite of these effects have been evaluated in previous studies, widespread propagation of actuated signal operation has not made so much in Korea. Because there are so many problems to use actuated signal as it is in side of roadway facilities. In this study, improved a actuation system for the national highway and evaluated it with field implementation.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.4 no.2 s.7
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• pp.33-43
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• 2005

In autumn 2000, the Korea Ministry of Construction and Transportation (MOCT) announced that Daejeon metropolitan city, Jeonju and Jeju were chosen to showcase deployment of Intelligent Transportation Systems(ITS). The program called the Advanced Transportation Systems Model Deployment Initiatives makes a significant step in Intelligent Transportation Infrastructure (In) in Korea. The Initiative is poised to increase the performance and efficiency of the area's roadway and transportation systems to meet growth demand. Three citie's $\$$50 million Model Deployment Initiative project is poised to increase the performance and efficiency of the area's roadway and transportation systems to meet growth demand. The effort particularly focused on the traveler information systems that should raise the level of ITS awareness in Korea. In this paper, project management, funding, private investment, procedures and detailed review of ITS Model Deployment Initiatives are discussed.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.9 no.6
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• pp.54-62
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• 2010

The scientific analysis of car-pedestrian accidents is not an easy task because of the characteristic of the accidents itself. Since the analysis involved human being, there were few experimental data that could be used for the analysis. The coefficient of friction of human body was the one of crucial data for accident analysis, but no field experiment report was available for various roadway conditions. This study intends to measure the coefficient of friction of human body through field studies. Results showed that the coefficient of friction of human body for dry asphalt pavement conditions was 0.59~0.62, and for dry concrete pavement conditions was 0.59~0.61. In addition, the coefficients for wet asphalt pavement and for wet concrete pavement conditions were 0.56~0.59 and 0.51~0.54 respectively, indicating 5.0% and 8.3% reduction compared to the dry conditions. The deduced coefficients were validated using the simulation program. It has been confirmed that the experiment values were close to the simulation results.

• International Journal of Highway Engineering
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• v.14 no.2
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• pp.73-81
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• 2012

The bicycle is an environment-friendly transport mode leading to a more sustainable transportation system. To innovatively increase the use of bicycle as a significant transport mode, bicycling-friendly roadway environment should be provided. From this perspective, the scientific and effective assessment of roadway environment in term of the bicyclist perception for safety and comfortability is of keen interest. This study develops a methodology for evaluation cycling environment using probe bicycles. A global positioning system(GPS) based speedometer was used to collect bicycle speed data. Cycling comfortability index(CCI) was derived for the purpose of evaluating cycling environment. The proposed CCI can be effectively used as an assessment tool in the field of bicycle transportation.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.3
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• pp.513-520
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• 2017

For the last 60years, North Korea has constructed a lot of roadway bridges with different standard from that used in South Korea, and since North Korea prefer to take advantage of train more than truck for long distance transport, the construction and maintenance of roadway bridges have not been constructed effectively. Upon these situations, an exact evaluation of the resisting capacity for bridges in North Korea has been required to check of any bridge can be used in time of war. This paper introduces an evaluation of bridges in North Korea on the basis of Military Load Classification (MLC). Three different types of concrete bridges are considered, and the numerical analysis and design calculation give the military loadings which can pass through the bridges in North Korea.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.17 no.5
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• pp.14-28
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• 2018

Thanks to technical improvement on the vehicle to vehicle communication and the intelligent transportation system, gradual introduction of the autonomous vehicles is expected soon in the market. The study analyzes the autonomous vehicles' impacts on the network efficiencies. In order to measure the network efficiencies, the study applies the sequential procedures that combines the microscopic and macroscopic simulations. The microscopic simulation attends to the capacity changes due to the autonomous vehicles' proportions on the roadway while the macroscopic simulation utilizes the simulation results in order to identify the network-wide improvement. As expected, the autonomous vehicles efficiently utilizes the existing capacity of the roadway than the human driving does. Particularly, the maximum capacity improvements are expected by the 190.5% on the expressway. The significant capacity change is observed when the autonomous vehicles' proportions are about 80% or more. These improvements are translated into the macroscopic model, which also yields overall network efficiency improvement by the autonomous vehicles' penetration. However, the study identifies that the market debut of the autonomous vehicles does not promise the free flow condition, which implies the possible needs of the system optimal routing scheme for the era of the autonomous vehicles.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.19 no.2
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• pp.18-35
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• 2020

Many human, roadway, and vehicle factors affect vehicle-pedestrian crashes. Especially, the roadway factors are easily defined and suitable for suggesting countermeasures. The characteristics of the road network are one of the roadway factors. The road network significantly influences behaviors and conflicts of drivers and pedestrians. A metropolitan city such as Seoul contains various types of road networks, and crash prevention strategy considering characteristics of the road network is required. In this study, we analyze the effects of road networks on vehicle-pedestrian crashes. In the study, high order road ratio, intersection ratio, high-low intersection ratio are considered as road network variables. Using Geographically Weighted Poisson Regression, crash frequencies in Dongs of Seoul are analyzed based on the road network variable as well as socioeconomic variables. As a result, Dongs are grouped by coefficient signs, and each group is suggested about improvement directions considering conflict situations.

• Journal of Distribution Science
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• v.21 no.8
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• pp.23-34
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• 2023

Purpose: To examine the economic effects of logistics under the influence of policies. Research design, data and methodology: This study is the first to use the panel data of 31 provinces and municipalities in China from 2012 to 2021, and use the OLS and DID models to evaluate whether the New Western Land-Sea Corridor (NWLSC) has promoted the economic development of the regions along the corridor. Results: The NWLSC has stimulated local economic growth by promoting the development of transportation, postal, and telecommunications industries along the corridor. Further, considering the locational differences of the regions along the NWLSC, we examined the differences in economic effects between regions along the Yangtze River and those not along the Yangtze River under the background of NWLSC implementation. We found that waterway and airway transport located along the NWLSC and in the Yangtze River Economic Belt (YREB) region can significantly promote economic growth. However, for regions located along the NWLSC but not in the YREB region, the impact of roadway, railway, and airway transport in these regions on economic growth is more significant. Conclusions: This study has important reference value on how to use logistics to promote the economic and cross-border commerce development of landlocked countries or regions.