• International Journal of Highway Engineering
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• v.15 no.2
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• pp.131-138
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• 2013

PURPOSES : The intents of the study are to identify the accident factors and to demonstrate the potentials of tobit model as a tool to study the number of accidents on arterial roads segments. METHODS : This paper uses a tobit regression as a methodology to analyze the factors affecting the number of accidents. In pursuing the above goal, this study gives particular attentions to analyzing the data of 2,446 accidents (1,610 in major arterial roads and 836 in minor arterial roads) occurred on arterial roads in 2007 to 2010. RESULTS : First, 3 accident models which were classified by total arterial roads, major arterial roads and minor arterial roads, and were all statistically significant were developed. Second, the exclusive right-turn lane as common variable, and the number of accident, traffic volume, number of lanes, link length, rate of median, number of entrances, number of pedestrian crossings, number of curves, number of bus stops and exclusive left-turn as specific variables of the models were selected. Finally, the paired sample t-test could not be rejected the null hypotheses of three types of models. CONCLUSIONS : Using data from vehicle accidents on arterial roads, the estimation results show that many factors related to roadway geometrics and traffic characteristics significantly affect to the number of accidents.

• International Journal of Highway Engineering
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• v.19 no.6
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• pp.155-164
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• 2017

PURPOSES : Owing to the growth of income and socio-economic levels, demands from road users have diversified. Accordingly, new road policies are being actively sought. The metropolitan city government of Busan has been focused on constructing and expanding roads to accommodate the increasing traffic demand. Given the increase in functional characteristics, we need to re-evaluate the hierarchy and function of roads, and specifically remodel the road planning and operations that fit into their functions. METHODS : First, this study focuses on introducing the minimum condition required to redefine the hierarchy of the roads. Second, the authors propose a new model that identifies the impact level of road hierarchy adopting discriminated analysis technique. RESULTS : Authors suggest that we redefine the hierarchy of roads in the central business distinct in Busan, and specifically the arterial roads in Busan, namely, Joonang-daero and Gaya-ro. These roads need to be reequipped with cross walks, a lower speed limit, and exclusive bus lanes to improve their accessibility. CONCLUSIONS : The authors found that the sub-arterial and collector roads have been subjected to excessive loads, owing to inappropriate functions being assigned to the main arterial road. Moreover, given that through traffic is concentrated on the sub-arterial and collector roads, over-speeding and other safety issues are consequently created.

• International Journal of Highway Engineering
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• v.13 no.1
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• pp.49-57
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• 2011

This study deals with the traffic accident of arterial link sections in the case of Cheongju. The purpose of the study is to develop the traffic accident model by the function of arterial links. In pursuing the above, this study gives particular attentions to developing the appropriate models using the accident data of main and minor arterial roads divided by 472 small link sections. The main results analyzed are as follows. First, as the t test on the accident characteristics of main and minor arterial roads shows that there are differences in the number of accident and EPDO(equivalent property damage only) between two roads, the development of models by function is analyzed to be appropriate. Second, it is analyzed that ZINB models are all statistically suitable to the number of accident and EPDO of main arterial roads. Third, the analysis shows that EPDOs of minor arterial roads fit to ZINB, and the number of the accident fit to ZIP model. Finally, the common variables of main arterial roads are evaluated to be the traffic volume and the number of inflection point, and those of minor be the average grade.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.17 no.2
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• pp.32-38
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• 2018

Studies on classification of national roads have been continued, but there is little research on the classification of urban arterial roads. Due to the increase of traffic volume, urban arterial roads do not perform well as main roads. In this paper, the function of urban arterial road was established by using cluster analysis using traffic characteristics. Traffic characteristics such as traffic volume, weekend coefficient and speed coefficient were used to establish the functions of 55 main arterial roads in Seoul. The results of this paper are compared with those of the method using AADT. The method using AADT classifies the characteristics according to the traffic volume of the whole lane. In this paper, however, the results are derived using the traffic volume per lane reflecting the actual traffic volume. In addition, the functional classification of the arterial roads in Seoul was compared with the results of this paper to verify that the traffic characteristics were reflected. As a result, the method presented in this paper is more effective in showing traffic characteristics than the current highway functional classification method, and the functional classification system will be helpful for road extension and planning design.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.5D
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• pp.485-496
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• 2010

An increase in number of vehicles owned by individuals worsens the conditions of parking in residential areas. So to speak, the pedestrians' safety is seriously threatened by illegally parked vehicles on the residential area roads. As a result, the number of vehicle-to-pedestrian accidents has been increasing annually. Also, illegal parking on arterial roads is increasingly becoming common, especially by cooommercial trucks. However, no solution has been found to reduce or eliminate accidents caused by vehicles illegally parked on readside. The result of this study provides the solutions to enhance the safety of residential area roads and arterial roads, from viewpoints of both long-term and short-term, by collecting data about the status of illegal parking and addressing critical problems.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.1
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• pp.34-52
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• 2019

This paper proposes an intelligent system performing an application with assistance of an Internet of Things (IoT) platform to control a traffic lights system. In our proposed systems, the traffic lights can be remotely controlled through the Internet. Based on IoT platform, the traffic conditions at different intersections of roads are collected and the traffic lights are controlled in a central manner. For the software part, the algorithm is designed based on the green wave theory to maximize the green bandwidth of arterial roads while addressing a challenging issue: the rapid changes of parameters including cycle time, splits, offset, non-fixed vehicles' velocities and traffic flow along arterial roads. The issue typically happens at some areas where the transportation system is not well organized like in Vietnam. For the hardware part, PLC S7-1200 are placed at the intersections for two purposes: to control traffic lights and to collect the parameters and transmit to a host machine at the operation center. For the communication part, the TCP/IP protocol can be done using a Profinet port embedded in the PLC. Some graphical user interface captures are also presented to illustrate the operation of our proposed system.

• Journal of the Korean Society of Safety
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• v.27 no.3
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• pp.141-146
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• 2012

This study deals with the accident model using panel data which are composed of time series data of 2005 through 2007 and cross sectional data of link sections in Cheongju. Panel data are repeatedly collected over time from the same sample. The purpose of the study is to develop the traffic accident model using the above panel data. In pursuing the above, this study gives particular attentions to deriving the optimal models among various models including TSCSREG (Time Series Cross Section Regression). The main results are as follows. First, 8 panel data models which explained the various effects of accidents were developed. Second, $R^2$ values of fixed effect models were analyzed to be higher than those of random effect models. Finally, such the variables as the sum of the number of crosswalk on intersections and sum of the number of intersections were analyzed to be positive to the accidents.

• Journal of the Korean housing association
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• v.21 no.5
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• pp.137-144
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• 2010

The purpose of this study is to clarify locational characteristics and the road systems of existing 22 old settlements in Cheongju downtown of Korea. These old settlements are classified largely into two types by geographical feature; Hill type located in ridge and Valley type in the valley from the ridge. The Hill type is further categorized into San-rock located on ridge and Gogae located on hillside, and the Valley type into closed large and small valley, that is, Daegok and Sogok by the shape and size of the valley. The road systems are classified into outer road, approaching road, inner road, and side road. In San-rock type villages, Inner road is changed side roads by new arterial road, and new ones become inner road. The outer road are almost cut off, but side roads maintain. In the case of the Gogae type, main road becomes inner road, maintain old hierarchical road, and in other cases, villages are formed around side roads derived from main road, and outer road and inner road are cut off. Among the Valley type, Daegok type maintains old hierarchical road, while for Sogok type, outer roads are cut off, and new roads are outer road.

• Journal of Korean Society of Transportation
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• v.14 no.2
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• pp.7-29
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• 1996

Traffic flow characteristics is analysed on eight multi-lane roads which are unsignalized in urban areas. Data of traffic flow rates by classification and average speed were gathered every ten minutes interval for twenty-four hours. Machine (NC-90A) was used to acquire the field data. The major purpose of this study is to build up speed-density models on urban arterial roads. Five different kinds of models were tested. Those models are Greenshields' model, Greenberg's model, modified Greenberg's model, Underwood's model and Drake's model. The modified Greenberg's model fits best at six points and the Greenshield's model fits best two points out of eight points. The breakpoint(Kb) of modified Greenberg's model is between 10 and 32 pcphpl. Capacity drawn from speed-volume relationships were appeared to be arround 2,000 and 2,200 pcphpl at the Hannam Bridge and the Hannam Overpass and 1,100 and 1,700 pcphpl at Namsan Tunnel(No1) and the beginning point of Gyeong-Bu Expressway.

• Journal of the Korean Society of Safety
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• v.25 no.3
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• pp.131-136
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• 2010

This study deals with the accident models of arterial link sections by vehicle type. The objectives are to analyze the characteristics of accidents, and to develop the models by type. In pursuing the above, this study uses the data of 414 accidents occurred on 24 major arterial links in 2007. The main results analyzed are as follows. First, the number of accidents is analyzed to account for about 47% in passenger car, 15% in SUV and 10% in trucks. Second, 3 Poisson regression models which are all statistically significant are developed using passenger car, SUV and truck as dependant variables. Finally, AADT and the number of traffic islands as common variables, and the number of pedestrian crossings, lanes, connecting roads, intersections(4-Leg), rate of medians and the number of bus stops as specific variables of the models are selected.