• Journal of Korean Society for Geospatial Information Science
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• v.6 no.1 s.11
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• pp.35-51
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• 1998

This article aims at presenting a new framework for traffic accident analysis by proposing a new methodology for the management of the accident data and by establishing the relationship between accidents and roadway characteristics within it For the first issue, authors introduced geographic information system (GIS) into the analysis framework of the accident data since it is believed that analysis based on GIS seems to provide more effective information in reducing accidents. Point-based, line-based, and polygon (grid)-based approaches were set of along with concrete examples. Especially, the location-based scores such as localization, specialization coefficients, and Tress score have been added to identify the intensity of certain accident types within study area or grids. The second issue addressed the equation formulation of accident and fatality numbers with roadway characteristics like number of intersections and road length in a grid with a sense that (1) accidents on roadways are the function of the roadway physical characteristics rather than the socio-economical secondary data (2) the equation can be applied to the any 'suggested' area, not just region or nation, and (3) the accident forecasting model should emphasize the accident location itself more than any other factors. Some equations based on those assumption have been derived along with some future research agenda.

• Journal of Korean Society of Transportation
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• v.25 no.4
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• pp.79-87
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• 2007

The interchanges of urban freeways have many problems with traffic operation due to high off-ramp flows and frequent congestion at adjacent intersections. The flow exiting from off-ramps is affected by the operational status and traffic volume conditions of the nearest signalized intersection. As a result, off-ramp flow cannot exit and the queue backs up the freeway mainline when queues from the signalized intersection form up to the junction of the off-ramp and street. The spacing between an off-ramp and an adjacent intersection is likely to determine the traffic conditions at the adjacent intersection. However, the current design guidelines do not consider such a factor. This study is to develop a model calculating the spacing between off-ramps and adjacent intersections considering the signal, traffic, and road conditions. The variables affecting the model in this study are effective green time (g/C), volume-capacity ratio (v/c), the number of lanes, and off-ramp volume. Various scenarios are designed to represent the effects of the variables and the road networks are constructed using VISSIM, which is a common traffic micro-simulation software package. The queue length is derived from VISSIM and this length is considered as the recommended spacing between the off-ramp and the adjacent intersection. Through the simulation analysis, regression models are developed to calculate the queue length reflecting the various conditions such as signals, traffic, and road configurations. The developed model can be used to create road design guidelines to determine the location of off-ramps in the planning stage.

• International Journal of Highway Engineering
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• v.11 no.3
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• pp.61-74
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• 2009

Traffic accident risk index Computation model's development apply traffic level of significance about area of road user group, road and street network area, population group etc.. through numerical formula or model by countermeasure to reduce the occurrence rate of traffic accidents. Is real condition that is taking advantage of risk by tangent section through estimation model and by method to choose improvement way to intersection from outside the country, and is utilizing being applied in part business in domestic. However, question is brought in the accuracy being utilizing changing some to take external model in domestic real condition than individual development of model. Therefore, selection intersection estimation element through traffic accidents occurrence present condition, geometry structure, control way, traffic volume, turning traffic volume etc. in 96 intersections in this research, and select final variable through correlation analysis of abstracted estimation elements. Developed intersection design model taking advantage of signal type, numeric of lane, intersection type, analysis of variance techniques through ANOVA analysis of three variables of intersection form with selected variable lastly, in signal crossing through three class intersection, distinction variable choice risk in model, no-signal crossing risk distinction analysis model and so on develop.

• Journal of Korean Society of Transportation
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• v.21 no.1
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• pp.91-102
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• 2003

There are two goals in this paper. The one is development of existing CA(Cellular Automata) model to explain more realistic deceleration process to stop. The other is the application of the updated CA model to forecasting simulation to predict short term link travel time that takes a key rule in finding the shortest path of route guidance system of ITS. Car following theory of CA models don't makes not response to leading vehicle's velocity but gap or distance between leading vehicles and following vehicles. So a following vehicle running at free flow speed must meet steeply sudden deceleration to avoid back collision within unrealistic braking distance. To tackle above unrealistic deceleration rule, “Slow-to-stop” rule is integrated into NaSch model. For application to interrupted traffic flow, this paper applies “Slow-to-stop” rule to both normal traffic light and random traffic light. And vehicle packet method is used to simulate a large-scale network on the desktop. Generally, time series data analysis methods such as neural network, ARIMA, and Kalman filtering are used for short term link travel time prediction that is crucial to find an optimal dynamic shortest path. But those methods have time-lag problems and are hard to capture traffic flow mechanism such as spill over and spill back etc. To address above problems. the CA model built in this study is used for forecasting simulation to predict short term link travel time in Kangnam district network And it's turned out that short term prediction simulation method generates novel results, taking a crack of time lag problems and considering interrupted traffic flow mechanism.

• Journal of the Korean Society for Railway
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• v.19 no.2
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• pp.224-233
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• 2016

Embedded Railway Systems (ERS) will be adapted for wireless trams and will be constructed along city roadways. An asphalt layer should be overlaid on top of the concrete slab used as the trackbed structure in order to ensure smoothness and surface levels equal to those of existing road pavement in downtown city areas. However, the characteristics of an asphalt layer when used as overlay pavement for an ERS are complicated and the behavior of this material is not yet well defined and understood. Therefore, in this study, laboratory shear and tensile bond strength tests were conducted to investigate the bonding behavior of an asphalt layer in a multilayered trackbed section of an ERS. For the laboratory tests, a waterproof coating material was selected as a bonding material between the asphalt overlay and a concrete specimen. Valuable design parameters could be obtained based on the tensile and shear bond strength test results, providing information about the serviceability and durability of the overlaid pavements to be constructed alongside the ERS for wireless trams. In addition, a deformation analysis to assess the tensile strain generated due to truck axle loads at the interface between the asphalt layer and the concrete slab was conducted to verify the stability and performance of the asphalt layer.

• Journal of Korean Society of Transportation
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• v.26 no.4
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• pp.63-76
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• 2008

The goals of this study are to develop travel time functions based on intersection delay and to analyze the applicability of the functions to traffic assignment models. The study begins with the premise that the existing assignment models can not effectively account for intersection delay time. In pursuing the goals, this study gives particular attention to dividing the link travel time into link moving time and stopped time at node, making the models based on such variables as the travel speed, volume, geometry, and signal data of signalized intersections in Cheongju, and analyzing the applicability of these models to traffic assignment. There are several major findings. First, the study presents the revised percentage of lanes (considering type of intersection) instead of g/C for calculating intersection delay, which is analyzed to be significant in the paired t-test. Second, the assigned results of applying these models to the Cheongju network in EMME/2 are compared with the data observed from a test car survey in Cheongju. The analyses show that the BPR models do not consider the intersection delay, but the modified uniform delay model and modified Webster model are comparatively well fitted to the observed data. Finally, the assigned results of applying these models are statistically compared with the test car survey data in assigned volume, travel time, and average speed. The results show that the estimates from the divided travel time model are better fitted to observed data than those from the BPR model.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.1828-1838
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• 2009

This study will analyze what is favorable of urban structure in order to introduce new transit system like bi-modal tram. As a reasonable transport mode in a city, the bi-modal tram needs to be considered with respect to the space structural pattern and city growth process. The result of this study may provide the basic resource that helps transport decision makers to decide how to introduce bi-modal tram by considering the urban structural characteristics. Also, the results that analyzed a functional characteristic of a bi-modal tram with a effective urban polices will be informative for practical use.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.24 no.4
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• pp.99-106
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• 2024

The problem of the bridges(Hasjiwokakero, Hasi) puzzle, which connects the bridge(edge) required by the island(vertex) without crossing the horizontal and vertical straight bridges except for the diagonal to form a connected network, is a barren ground for research without any related research. For this problem, there is no algorithm that presents a generalized exponential time brute-force or branch-and-bound method. This paper obtained the initial solution of the lattice graph by drawing a grid without diagonal lines for a given BP, removing unnecessary edges, and supplementing essential bridges. Next, through insufficient island pair path matching, the method of adding insufficient edges to the route and deleting the crossed surplus edges(bridges) was adopted. Applying the proposed algorithm to 24 benchmarking experimental data showed that accurate solutions can be obtained for all problems.

• Proceedings of The Korean Society of Health Promotion Conference
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• 2005.09a
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• pp.197-230
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• 2005

일본의 Soyo town에서 진행된 건강도시사업은 건강증진 프로그램 모형을 통하여 건강한 도시를 건설하겠다는 슬로건을 가지고 주민들이 참여하여 자신의 건강관리능력을 함양하고 서로의 장점을 공유하는 것을 사명으로 하고 있다. 또한 삶의 질 향상, 주관적 건강상태 향상, 삶의 만족도 향상, 정서적 유대감 향상, 수입증가 그리고 조기사망의 감소를 구체적 목적으로 설정하고 있다. 이러한 목적을 달성하게 위한 매우 실제적이며 수량화된 목표들이 설정되어 있다. 1992년에 사전조사를 실시하고 1996년과 2002년에 사후 조사를 실시하였다. 프로그램 내용과 과정에는 보건의료전문가와 시설에 대한 정비, 평가에 대한 계획, 학교를 포함한 포괄적인 보건의료시스템이 포함된다. 모든 부문은 자신들이 설정한 보건정책 결과에 대하여 모니터링을 진행하며 적절한 정책을 다시 설정하고 수량화된 목표를 설정하며 프로그램을 수행한다. 프로그램 수행의 가장 중요한 원칙은 사업의 기획, 수행, 평가 과정에 주민이 최우선적으로 참여한다는 점이다. Soyo town은 사업을 위하여 학교 및 지역 내 사조직과 협력하고 모든 사업의 기획과정에 다양한 구성원들을 참여시켰는데 이는 건강자원 개발에 있어 매우 중요하게 실천되어야 하는 문제이다. 특히 모든 Soyo town의 주민들이 참여하는 것을 원칙으로 하였다. 주민들은 건강관련 자원의 배치상태와 과학적 근거를 고려하여 효과적인 사업을 선정하는 것을 포함한 모든 사업의 과정에 참여하였다. 바람직한 생활양식을 향상시키기 위하여 식품회사, 자원단체 그리고 사회적 관계망 그리고 지역의 단체급식시설, 식당 등이 파악되었으며, 요양원, 가사도우미, 공중보건간호사, 방문간호사, 사회사업가로 구성된 보건의료 시설과 인력들이 협력하였다. 사업이 주민의 건강을 향상시켰는가와 건강향상에 사업이 효과적이었는지를 판단하기 위해서 평가가 진행되었는데, 서비스 제공자 뿐 아니라 소비자와 주민들도 평가를 수행하였다. Soyo town의 건강도시사업의 평가 결과, 조기사망률이 1988년 22.1%이 1992년 18.2%로, 1998년 15.6%로 감소하였다. 또한 주관적인 건강상태는 1988년 48%에서 1992년 67.1%로, 1998년 71.5%로 증가하였다. 전반적으로 주관적 건강상태, 사회적 관계망, 보건의료서비스에 대한 접근성은 증가하였으며, 조기사망, 의료비용은 감소하였다. 한편 보건의료부문의 질적인 향상을 가져왔으며, Soyo town은 건강한 도시의 명성을 얻게 되었다. 사업의 효과성을 향상시킨 요인은 주민 개개인들에게 사업의 기획과정에 처음부터 참여할 기회가 주어졌다는 점과 자원개발에 있어 기존자원의 재개발에 우선순위를 두었다는 점이었다. 효과적인 사업의 수행을 위하여 행정부, 주민, 건강관련 단체들은 수단과 방법에 관한 정보를 교환하는 것이 중요하다. 사업의 기획단계에 모든 이해당사자들이 참여하여 각자의 역할분담을 명확히 하는 것이 필요하며, 건강증진은 개인의 노력 뿐 아니라 사회적 환경의 개선과 자원의 개발을 통해서 달성되는 것이므로 주민들은 건강증진을 위한 환경개선을 위해 노력도 병행되어야 한다.

• Journal of Korean Society for Geospatial Information Science
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• v.8 no.1 s.15
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• pp.51-63
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• 2000

Dynamic traffic assignment(DTA) has been a topic of substantial research during the past decade. While DTA is gradually maturing, many aspects of DTA still need improvement, especially regarding its formulation and solution algerian Recently, with its promise for In(Intelligent Transportation System) and GIS(Geographic Information System) applications, DTA have received increasing attention. This potential also implies higher requirement for DTA modeling, especially regarding its solution efficiency for real-time implementation. But DTA have many mathematical difficulties in searching process due to the complexity of spatial and temporal variables. Although many solution algorithms have been studied, conventional methods cannot iud the solution in case that objective function or constraints is not convex. In this paper, the genetic algorithm to find the solution of DTA is applied and the Merchant-Nemhauser model is used as DTA model because it has a nonconvex constraint set. To handle the nonconvex constraint set the GENOCOP III system which is a kind of the genetic algorithm is used in this study. Results for the sample network have been compared with the results of conventional method.