• The Journal of the Korea institute of electronic communication sciences
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• v.12 no.1
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• pp.9-16
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• 2017

In this paper, we introduce a warning message providing methodology by considering the elderly's walking behavior in V2P(: Vehicle-to-Pedestrian) communication systems. Using the elderly's accident records in Kyounggi-do area from 2011 to 2014, the elderly's accident behaviors are analyzed by categorizing accidents as road type (single road/ crossing road), existence of traffic signal (with signal/ without signal), existence of crosswalk (crosswalk/ jaywalk), cause of accident (jaywalk/ signal violation/ carelessness accident/ Etc.). In addition, the elderly's behavior variable and vehicle speed are applied, then some threshold values are utilized in a warning message providing in conflict area. Finally, we propose a distance which can protect an accident depending on the elderly's walking speed, safety margin and vehicle speed. By applying the results of this research to the V2P/P2V communication based road safety message providing system with the elderly's walking behavior, it may be helpful to reduce accident rate of the elderly.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.11 no.4
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• pp.1-9
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• 2012

This study deals with the operation effectiveness of roundabout. The objective of this study was to analyze the operational effectiveness of roundabout based on the operation of pedestrian signal. For pursuing the above, VISSIM was as a traffic simulation program. this study gives particular attention to analyzing the 1,680 scenarios by operation of Pedestrian Signal(7 cases), roundabout type(2 cases), pedestrian volume(8 cases) and entering volume(15 cases). The main results analyzed are as follows. First, the operational effectiveness analyzed by 2 type of 4-legged 1-lane roundabout and 6 type of 4-legged 2-lane were evaluated to be better than that by the others type. Second, the average delay time analyzed by operation of pedestrian signal were evaluated to be less than that by unsignalized pedestrian crossing. Finally, the average delay time analyzed by pedestrian crossing were decreased 8.18% than that by staggered pedestrian crossing in 4-legged 1-lane. However, the average delay time analyzed by staggered pedestrian crossing were evaluated to be decreased 36.53% than that by pedestrian crossing in 4-legged 2-lane.

• Journal of Korean Society of Transportation
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• v.22 no.7 s.78
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• pp.131-137
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• 2004

Conventional traffic signal optimization models assume that green intervals for pedestrian crossings are given as exogenous inputs such as minimum green intervals for straight-ahead movements. As the result, in reality, the green intervals of traffic movements may not distribute adequately by the volume/saturation-flow of them. In this paper, we proposed signal optimization models formulated in BMILP to integrate pedestrian crossings into traffic movements under under-saturated traffic flow. The model simultaneously optimizes traffic and pedestrian movements to minimize weighted queues of primary queues during red interval and secondary queues during queue clearance time. A set of linear objective function and constraints set up to ensure the conditions with respect to pedestrian and traffic maneuvers. Numerical examples are given by pedestrian green intervals and the number of pedestrian crossings located at an arm. Optimization results illustrated that pedestrian green intervals using proposed models are greater than those using TRANSYT-7F, but opposite in the ratios of pedestrian green intervals to the cycle lengths. The simulation results show that proposed models are superior to TRANSYT-7F in reducing delay, where the longer the pedestrian green interval the greater the effect.

• Proceedings of the Korean Information Science Society Conference
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• 2006.06c
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• pp.226-228
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• 2006

관심사 분리는 소프트웨어 공학에서 핵심 문제로 다루어왔다. 기존의 OOD나 CBD등은 관심사를 분리하여 모듈화함으로써 프로그램 개발 및 유지보수를 용이하도록 발전해왔다. 하지만, 에러 처리나 로깅과 같이 여러 모듈에 산재되어 실행되는 횡단 관심사는 기존의 방법으로 해결하기 어려웠다. AOP는 이와 같은 횡단 관심사를 처리하려는 데 목적을 두고 제안된 방법으로 기존의 OOD나 CBD의 단점을 보완하면서 병행적으로 발전해왔다[1]. AOP가 나타난 가장 큰 특징은 기존의 개발 방법론을 기반으로 핵심 관심사를 개발하고 해결하기 어려운 횡단 관심사는 AOP로 개발하려는데 초기 목적을 두고 있다. 하지만, 대부분의 연구가 초기 요구사항 분석 단계에서 관심사를 명시하는데 초점을 두고 있을 뿐 구현 단계에서 효율적인 접근 방법은 아직 부족한 편이다. 본 논문에서는 Java와 AspectJ를 이용하여 구현한 간단한 사례 연구를 적용한 AOP 개발 프레임워크를 제안한다. AOP 개발 프레임워크에서는 관심사 분리, 구현, 평가의 세 단계를 기술한다. 이 중 구현단계에서는 핵심 관심사와 횡단 관심사 구현에 초점을 두고 AOP 기법에 쉽게 접근할 수 있는 방법을 기술하고 있다. 프레임워크는 프로그램 개발을 보다 용이하게 하고 확장 및 유지보수시 많은 시간을 단축시키려는데 있다.

• Ecology and Resilient Infrastructure
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• v.7 no.4
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• pp.320-326
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• 2020

The present study aimed to assess the longitudinal connectivity owing to migrant characteristics of the target fish. The study area was Wonju-cheon Stream, and the target species were Zacco platypus and Minnows. The HEC-RAS model was used for the computation of the flow, and the ICE (Information sur la Continuite Ecologique) method was used to analyze the longitudinal connectivity. The longitudinal connectivity was assessed using the minimum overflow height, velocity, and depth of the cross sectional structure of a plunge pool and considering the swimming speed of the target fish. Simulation results indicated that the longitudinal connectivity scores for the Zacco platypus and Minnows were approximately 76 and 23, respectively.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.6
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• pp.1075-1082
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• 2016

In order to calculate the optimum installation interval between a speed hump and hump type crosswalk that are installed continuously in succession, this study examined the speed of a vehicle that passes different intervals between speed humps and hump type crosswalks from the approach section of a roundabout having a maximum speed limit of 30km/h; analyzed the effects of speed humps and hump type crosswalks installed continuously in succession on vehicle driving speed; and simulated the optimum installation height of hump type crosswalk. As a result, the following conclusion was drawn. First, it was found that the optimum interval between a speed hump and hump type crosswalk, which are the representative traffic calming techniques for reducing vehicle speed, to control vehicle speed under 30km/h is 30m. Second, as a result of comparing the deceleration of a vehicle that pass hump type crosswalks, it was found that if the installation interval is 65 m and above, a speed hump and hump type crosswalk had no effect. Therefore, it is desirable that the maximum installation interval between a speed hump and hump type crosswalk for controlling vehicle speed within a fixed road section should not exceed 65m. Third, the analysis showed that the optimum installation height of hump type crosswalk is 6-8cm in case vehicle speed at the approach section is 20km/h or lower, 8-10cm in case of 30km/h, and 10cm in case of 30km/h or higher, respectively. Fourth, even at a road section on which a speed hump and hump type crosswalk are installed, speed reduction effects may sometimes be insignificant due to a driver's studying effect, traffic conditions and so on. Thus, it is judged that speed reduction effects will be greater if several traffic calming techniques such as speed hump, chicane, and choker are applied at the same time. Therefore, in case of applying traffic calming techniques for the purpose of reducing vehicle speed in order to promote pedestrian safety, the composite application of several techniques should be considered.

• Journal of the Korean Society for Railway
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• v.16 no.3
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• pp.207-216
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• 2013

The components of concrete track (rail and rail fastening system) in railway bridge deck ends are damaged and deteriorated by track-bridge interaction forces such as uplift forces and compression forces owing to their structural flexural characteristics (bridge end rotation). This had led to demand for alternatives to improve structural safety and serviceability. In this study, the authors aim to develop a transition track to enhance the long term workability and durability of concrete track components in railway bridge deck ends and thereby improve the performance of concrete track. A time-history analysis and a three-dimensional finite element method analysis were performed to consider the train speed and the effect of multiple train loads and the results were compared with the performance requirements and German standard for transition track. Furthermore, two specimens, a normal concrete track and a transition track, were fabricated to evaluate the effects of application of the developed transition track, and static tests were conducted. From the results, the track-bridge interaction force acting on the track components (rail displacement, rail stress, and clip stress) of the railway bridge deck end were significantly reduced with use of the developed transition track compared with the non-transition track specimen.

• Proceedings of the Korean Society of Disaster Information Conference
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• 2017.11a
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• pp.249-250
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• 2017

현재 전체 교통사고 건수는 감소하는 추세이지만 보행자 교통사고는 점점 증가하고 있다. 또한 보행자 교통사고 중 고령보행자 교통사고건수 비율이 높은데 이에 따른 원인분석과 예방 대책에 관한 연구가 필요하다. 이에 본 연구는 고령보행자 다발지역을 분석하여 사고 원인을 비교분석 하는 것이다. 다발지역 분석결과 대부분 보행자가 횡단 중 일 때 사고가 발생하였고, 도로형태에서는 교차로, 신호기가 없는 일반도로에서 많이 발생했다. 이에 무단횡단을 방지하는 시설 확대 설치와, 무단횡단의 위험성을 알리는 안전교육의 필요성이 있다고 본다.

• Journal of Korean Society of Transportation
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• v.24 no.5 s.91
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• pp.57-66
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• 2006

This paper presents new pedestrian signal timings considering pedestrian demand Pedestrian characteristics, and land use which were obtained by Pedestrian characteristics field survey and pedestrian signal operation survey. Pedestrian signal timings suggested were compared to the existing pedestrian signal timings by using real field data. pedestrian characteristics field survey was conducted to collect pedestrian crossing speed data and reaction time data. Sixteen areas in Seoul were selected for the data collection. The average pedestrian crossing speed was 1.30m/sec and the 15th Percentile speed was 1.11m/sec. The average reaction time was 2.24 seconds. Pedestrian crossing speed differs by land use, road width. pedestrian age, sex, and number of Pedestrians. Reaction time also differs by road width, pedestrian age, and number of pedestrians. Statistical testing was performed to secure reliability of the collected data.

• Journal of Korean Society of Forest Science
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• v.107 no.3
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• pp.278-286
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• 2018

This study examined the damage characteristics through investigation for a total of 10 factors (longitudinal position, crossing position, soil type, collecting well volume, outlet position, water apron material, waterway existence, pipe culvert diameter, pipe culvert gradient, pipe culvert height) affecting outlet damages of forest road cross drainage for forest roads in the Research Forest of Kangwon National University. We predicted outlet damages of forest road cross drainage for forest roads using a discriminant analysis Results showed that longitudinal position, crossing position, soil type and pipe culvert height did not affect damages caused to forest road cross drainage. Most influential factors affecting outlet damages were outlet position, waterway existence, pipe culvert diameter, pipe culvert gradient and collecting well volume, respectively. The discriminant ratio calculated from the developed discriminant function was 68.8% which is reasonably reliable.