• Title/Summary/Keyword: Roadways

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Ab-Anbar, the Ancient Underground Water Houses of Iran

  • Yazdi, J. Tababaee;Han, Moo-Young
    • Proceedings of the Korea Water Resources Association Conference
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    • 2008.05a
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    • pp.1438-1441
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    • 2008
  • Throughout the history, the people of Iran have battled the dryness by innovations to preserve every drop of water that lands from the rare clouds, or from a stream flowing out of distant springs. Water is precious and held with highest respect, whether stored for drinking at an Ab-Anbar, or for washing and farming at the Houz in the middle of their oasis homes and orchards, or sourced at a Qanat spring or Jooy under ground. How it is that drinking water as cold as a mountain fall is found in desert of Iran? Ab-Anbar is an ancient means of water preservation and cooling through anunderground building structure. These underground structures have been present in Khorasan and other desert provinces of Iran as public or private water storage facilities, widely used before the installation of public plumbing systems in the late 1950s. Although many of these structures are still functional, most have been protected by government for restoration or viewing by the public as historical heritage. Khorasan natural dry climate and the massive surrounding deserts have been a breeding ground for many designs of Ab-Anbars. Today the existing number of such facilities stands in the province of Khorasan. Usually these structures were built in populated areas, also there are some forms of such structures on old trade routes and roadways leading to and from populated towns. This paper considers the history of Ab-Anbars in Khorasan as well as other relevant aspects such as types, components, construction methods and materials, filling and withdrawal systems.

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An Evaluation of Speed Monitoring Display about Reducing Traffic Speed (가변속도 표출기의 속도저감 효과평가에 관한 연구)

  • Song Ki-Uok;Lee Eui-Eun
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.4 no.1 s.6
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    • pp.97-106
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    • 2005
  • Since traffic engineering in 1950's, 'speed control technology' has experienced tremendous growth and developed constantly. However, speeding remains a major safety concern on many roadways. Many crashes is believed to be the result of driving too fast. Recently the speed reduction device, the speed monitoring display with ITS technologies have developed and introduced in many countries including our nation, Korea. Therefore This paper describes an evaluation of the use of a speed monitoring display, speed limit sign, and school zone sign. Two conditions were evaluated; without installation of Speed Monitoring Display, in Operation of Speed Monitoring Display.

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Tight Budgets and Roadway Maintenance: The Need for Further Study of the Conversion/Reconversion Scenario for Low-Volume Roadways (예산 및 도로 유지관리 : 저교통량 도로의 포장 변경을 위한 추가연구의 필요성)

  • Kim, Hyun Hwan;Humphries, Evan;Hu, Jiong;Lee, Soon Jae;Lee, Moon Sup
    • International Journal of Highway Engineering
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    • v.17 no.3
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    • pp.1-12
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    • 2015
  • PURPOSES : This paper presents a description of the current issues facing road managers regarding the surface-type conversion of low-volume roads for cost savings. METHODS: The paper reviews previous works conducted toward this end, acknowledges gaps in the current research, and lays out what information is needed for further studies. RESULTS : If the cost to maintain an unsurfaced road is less than the cost of maintaining a surfaced road, then there is potential for cost savings for the management agency. However, the problem is bigger than simply maintaining the roads that already exist. If unsurfaced roads prove to be more economical than surfaced roads, then the cost to convert from a surfaced to an unsurfaced roadway, and vice versa, when necessary, must also be examined. CONCLUSIONS : No other studies have addressed the un-surfacing of a road for cost savings, and it is therefore unknown whether substantial savings can be realistically obtained by converting from a surfaced to an unsurfaced road. To determine whether a conversion policy would be a viable option, additional data and research are needed.

Determining the Appropriate Installation Angle of Skewed Sensor to Measure Vehicle Wandering (차량 원더링 계측을 위한 사선센서 적정 설치각도 결정)

  • Oh, Ju-Sam;Jang, Kyung-Chan;Kim, Min-Sung;Jang, Jin-Hwan
    • International Journal of Highway Engineering
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    • v.10 no.3
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    • pp.79-86
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    • 2008
  • This paper proposed the appropriate installation angle of skewed sensors for measuring vehicle wandering data, which are collected to figure out the location of dynamic weight of a moving vehicle on roadways. We developed a device using tape-switch sensors and a computer program and collected vehicle wandering data with the device and probe vehicles. As a result, the steeper the skewed sensor was installed, the lower the error was shown. However, we could not collect proper data when a skewed sensor was set up higher than $30^{\circ}$ due to tandem axle. Therefore, this study suggested the appropriate angle of skewed sensors as a degree of $20^{\circ}$ to $25^{\circ}$ for gathering wandering data.

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Practical fatigue/cost assessment of steel overhead sign support structures subjected to wind load

  • van de Lindt, John W.;Ahlborn, Theresa M.
    • Wind and Structures
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    • v.8 no.5
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    • pp.343-356
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    • 2005
  • Overhead sign support structures number in the tens of thousands throughout the trunk-line roadways in the United States. A recent two-phase study sponsored by the National Cooperative Highway Research Program resulted in the most significant changes to the AASHTO design specifications for sign support structures to date. The driving factor for these substantial changes was fatigue related cracks and some recent failures. This paper presents the method and results of a subsequent study sponsored by the Michigan Department of Transportation (MDOT) to develop a relative performance-based procedure to rank overhead sign support structures around the United States based on a linear combination of their expected fatigue life and an approximate measure of cost. This was accomplished by coupling a random vibrations approach with six degree-of-freedom linear dynamic models for fatigue life estimation. Approximate cost was modeled as the product of the steel weight and a constructability factor. An objective function was developed and used to rank selected steel sign support structures from around the country with the goal of maximizing the objective function. Although a purely relative approach, the ranking procedure was found to be efficient and provided the decision support necessary to MDOT.

Characteristics of Air Pollutant Concentrations Near Major Roadways in Daegu (대구지역 주요 도로변 대기오염물질의 농도 특성)

  • Jo, Wan-Kuen;Choi, Sung-Rak
    • Journal of Environmental Science International
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    • v.15 no.8
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    • pp.737-744
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    • 2006
  • Present study was designed to characterize the concentrations of major roadside air pollutants in Daegu and to compare with those of Seoul and Busan. Evaluated were the exceedance frequence of mean concentrations of target compounds(CO, NO$_2$, O$_3$, PM$_{10}$, SO$_2$) and the relationship for time variation. Two air pollution monitoring stations(one roadside station and one residential station) in Daegu were selected for this study. In addition, one roadside monitoring station from each of Seoul and Busan was chosen for the comparison of Daegu monitoring stations. The data analyzed in the current study were collected from 1998 to 2000 by Daegu Regional Environmental Management Office. The roadside concentrations of NO2 and PM to and the exceedance frequency of ambient air standard levels in Daegu were higher than those of Seoul and Busan. Except 03, the roadside concentrations of all target compounds showed following three distinguished patterns; first, possibly due to increased traffic density, the concentrations increased from 0500 to 0900(LST), second, the concentrations decreased from 0900 to 1700(LST) possibly due to the increased wind velocity and decreased traffic density, and finally, increased traffic density, the concentrations increased again from 1700 to 2100(LST). An implication was that major air pollution sources shifted from residential area to road-area during rush hours.

A Study on the Integrated Ventilation Control Algorithm for Road Tunnels (다중터널의 통합환기제어 알고리즘 연구)

  • Kim, Tae-Hyung;Hong, Dae-Hie;Chu, Baek-Suk;Kim, Dong-Nam;Keum, Jae-Sung;Kim, Jin
    • Proceedings of the SAREK Conference
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    • 2008.11a
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    • pp.405-409
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    • 2008
  • Over 70% of the land is mountains in Korea, so that many roadways naturally includes tunnels. The air flow inside tunnel has complex characteristics, such that a new flow field is formed by following vehicles passing through the tunnel before previous flow field is stabilized. Due to these time delayed-transient characteristics, the ventilation facility requires the complex control algorithm that can handle adaptive and predictive controls. Also, it needs to be closely related to the disaster prevention system. The technology to integrate these system determines the success of TGMS. The pollutant levels exhausted from the vehicles passing through tunnel depend on vehicle years and passing velocity. They also depend on the slope and altitude of the tunnel. In order to solve this problem, an algorithm for estimating the compensating factors for calculating on design capacity of ventilation facilities was developed. Also, an integrated ventilation control algorithm with disaster prevention program to operate several tunnels was developed based on TGMS.

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Gradation Image Processing for Text Recognition in Road Signs Using Image Division and Merging

  • Chong, Kyusoo
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.13 no.2
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    • pp.27-33
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    • 2014
  • This paper proposes a gradation image processing method for the development of a Road Sign Recognition Platform (RReP), which aims to facilitate the rapid and accurate management and surveying of approximately 160,000 road signs installed along the highways, national roadways, and local roads in the cities, districts (gun), and provinces (do) of Korea. RReP is based on GPS(Global Positioning System), IMU(Inertial Measurement Unit), INS(Inertial Navigation System), DMI(Distance Measurement Instrument), and lasers, and uses an imagery information collection/classification module to allow the automatic recognition of signs, the collection of shapes, pole locations, and sign-type data, and the creation of road sign registers, by extracting basic data related to the shape and sign content, and automated database design. Image division and merging, which were applied in this study, produce superior results compared with local binarization method in terms of speed. At the results, larger texts area were found in images, the accuracy of text recognition was improved when images had been gradated. Multi-threshold values of natural scene images are used to improve the extraction rate of texts and figures based on pattern recognition.

Evaluation of the Permanent Deformation Behavior on Geosynthetics-Reinforced Asphalt Pavement by using the Wheel Tracking Tests (휠트래킹 시험을 통한 토목섬유시트 보강 아스팔트포장의 소성변형 거동특성 평가)

  • Cho, Sam-Deok;Lee, Dae-Young;Kim, Jin-Hwan;Kim, Nam-Ho
    • Journal of the Korean Geosynthetics Society
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    • v.2 no.3
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    • pp.39-46
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    • 2003
  • The major pavement distress types found in the domestic roadways include rutting, fatigue cracking, and reflection cracking which are results of the environment and repeated traffic loads. These distresses usually occur before pavements approach their design life, and therefore, a significant amount of national budget is spent for maintenance of roadway pavements. The purpose of this study is to establish a geosynthetics-asphalt pavement system. For the study, wheel tracking tests are conducted to analyze the controlling effect of geosynthetics on rutting of asphalt pavement. On the basis of these works, the reinforcement effect of geosynthetics on the rutting of the asphalt pavement is clarified and deformation characteristics of geosynthetics-asphalt mixture is examined.

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Safety Performance Evaluation Scenarios for Extraordinary Service Permission of Autonomous Vehicle (자율주행 자동차 임시운행 허가를 위한 안전 성능 평가 시나리오)

  • Chae, Heungseok;Jeong, Yonghwan;Yi, Kyongsu;Choi, Inseong;Min, Kyongchan
    • Transactions of the Korean Society of Automotive Engineers
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    • v.24 no.5
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    • pp.495-503
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    • 2016
  • Regulation for the testing and operation of autonomous vehicles on public roadways has been recently developed all over the world. For example, the licensing standards and the evaluation technology for autonomous vehicles have been proposed in California, Nevada and EU. But specific safety evaluation scenarios for autonomous vehicles have not been proposed yet. This paper presents safety evaluation scenarios for extraordinary service permission of autonomous vehicles on highways. A total of five scenarios are selected in consideration of safety priority and real traffic situation. These scenarios are developed based on existing ADAS evaluation and simulation of autonomous vehicle algorithm. Also, Safety evaluation factors are developed based on ISO requirements, other papers and the current traffic regulations. These scenarios are investigated via computer simulation.