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Sample records for two-lane rural roads

  1. Assisted overtaking : An assessment of overtaking on two-lane rural roads

    NARCIS (Netherlands)

    Hegeman, G.

    2008-01-01

    At the start of the 21st century overtaking on two-lane rural roads is a major traffic safety problem. However, this dissertation research demonstrates that most drivers are perfectly able to safely perform these manoeuvres. Their time spent in the left lane is about eight seconds. Preparing

  2. Investigation of pedestrian crashes on two-way two-lane rural roads in Ethiopia.

    Science.gov (United States)

    Tulu, Getu Segni; Washington, Simon; Haque, Md Mazharul; King, Mark J

    2015-05-01

    Understanding pedestrian crash causes and contributing factors in developing countries is critically important as they account for about 55% of all traffic crashes. Not surprisingly, considerable attention in the literature has been paid to road traffic crash prediction models and methodologies in developing countries of late. Despite this interest, there are significant challenges confronting safety managers in developing countries. For example, in spite of the prominence of pedestrian crashes occurring on two-way two-lane rural roads, it has proven difficult to develop pedestrian crash prediction models due to a lack of both traffic and pedestrian exposure data. This general lack of available data has further hampered identification of pedestrian crash causes and subsequent estimation of pedestrian safety performance functions. The challenges are similar across developing nations, where little is known about the relationship between pedestrian crashes, traffic flow, and road environment variables on rural two-way roads, and where unique predictor variables may be needed to capture the unique crash risk circumstances. This paper describes pedestrian crash safety performance functions for two-way two-lane rural roads in Ethiopia as a function of traffic flow, pedestrian flows, and road geometry characteristics. In particular, random parameter negative binomial model was used to investigate pedestrian crashes. The models and their interpretations make important contributions to road crash analysis and prevention in developing countries. They also assist in the identification of the contributing factors to pedestrian crashes, with the intent to identify potential design and operational improvements. Copyright © 2015. Published by Elsevier Ltd.

  3. Identifying significant predictors of head-on conflicts on two-lane rural roads using inductive loop detectors data.

    Science.gov (United States)

    Shariat-Mohaymany, Afshin; Tavakoli-Kashani, Ali; Nosrati, Hadi; Ranjbari, Andisheh

    2011-12-01

    To identify the significant factors that influence head-on conflicts resulting from dangerous overtaking maneuvers on 2-lane rural roads in Iran. A traffic conflict technique was applied to 12 two-lane rural roads in order to investigate the potential situations for accidents to occur and thus to identify the geometric and traffic factors affecting traffic conflicts. Traffic data were collected via the inductive loop detectors installed on these roads, and geometric characteristics were obtained through field observations. Two groups of data were then analyzed independently by Pearson's chi-square test to evaluate their relationship to traffic conflicts. The independent variables were percentage of time spent following (PTSF), percentage of heavy vehicles, directional distribution of traffic (DDT), mean speed, speed standard deviation, section type, road width, longitudinal slope, holiday or workday, and lighting condition. It was indicated that increasing the PTSF, decreasing the percentage of heavy vehicles, increasing the mean speed (up to 75 km/h), increasing DDT in the range of 0 to 60 percent, and decreasing the standard deviation of speed significantly increased the occurrence of traffic conflicts. It was also revealed that traffic conflicts occur more frequently on curve sections and on workdays. The variables road width, slope, and lighting condition were found to have a minor effect on conflict occurrence. To reduce the number of head-on conflicts on the aforementioned roads, some remedial measures are suggested, such as not constructing long "No Passing" zones and constructing passing lanes where necessary; keeping road width at the standard value; constructing roads with horizontal curves and a high radius and using appropriate road markings and overtaking-forbidden signs where it is impossible to modify the radius; providing enough light and installing caution signs/devices on the roads; and intensifying police control and supervision on workdays

  4. Calibration of the inertial consistency index to assess road safety on horizontal curves of two-lane rural roads.

    Science.gov (United States)

    Llopis-Castelló, David; Camacho-Torregrosa, Francisco Javier; García, Alfredo

    2018-05-26

    One of every four road fatalities occurs on horizontal curves of two-lane rural roads. To this regard, many studies have been undertaken to analyze the crash risk on this road element. Most of them were based on the concept of geometric design consistency, which can be defined as how drivers' expectancies and road behavior relate. However, none of these studies included a variable which represents and estimates drivers' expectancies. This research presents a new local consistency model based on the Inertial Consistency Index (ICI). This consistency parameter is defined as the difference between the inertial operating speed, which represents drivers' expectations, and the operating speed, which represents road behavior. The inertial operating speed was defined as the weighted average operating speed of the preceding road section. In this way, different lengths, periods of time, and weighting distributions were studied to identify how the inertial operating speed should be calculated. As a result, drivers' expectancies should be estimated considering 15 s along the segment and a linear weighting distribution. This was consistent with drivers' expectancies acquirement process, which is closely related to Short-Term Memory. A Safety Performance Function was proposed to predict the number of crashes on a horizontal curve and consistency thresholds were defined based on the ICI. To this regard, the crash rate increased as the ICI increased. Finally, the proposed consistency model was compared with previous models. As a conclusion, the new Inertial Consistency Index allowed a more accurate estimation of the number of crashes and a better assessment of the consistency level on horizontal curves. Therefore, highway engineers have a new tool to identify where road crashes are more likely to occur during the design stage of both new two-lane rural roads and improvements of existing highways. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. Analysis of the injury severity of crashes by considering different lighting conditions on two-lane rural roads.

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    Jafari Anarkooli, A; Hadji Hosseinlou, M

    2016-02-01

    Many studies have examined different factors contributing to the injury severity of crashes; however, relatively few studies have focused on the crashes by considering the specific effects of lighting conditions. This research investigates lighting condition differences in the injury severity of crashes using 3-year (2009-2011) crash data of two-lane rural roads of the state of Washington. Separate ordered-probit models were developed to predict the effects of a set of factors expected to influence injury severity in three lighting conditions; daylight, dark, and dark with street lights. A series of likelihood ratio tests were conducted to determine if these lighting condition models were justified. The modeling results suggest that injury severity in specific lighting conditions are associated with contributing factors in different ways, and that such differences cannot be uncovered by focusing merely on one aggregate model. Key differences include crash location, speed limit, shoulder width, driver action, and three collision types (head-on, rear-end, and right-side impact collisions). This paper highlights the importance of deploying street lights at and near intersections (or access points) on two-lane rural roads because injury severity highly increases when crashes occur at these points in dark conditions. Copyright © 2016 Elsevier Ltd and National Safety Council. All rights reserved.

  6. Capacity of two-lane roads

    CSIR Research Space (South Africa)

    Kennedy, DA

    1991-01-01

    Full Text Available Relationships of speed vs density, volume and percentage loop occupation are investigated. The effect of differing directional splits in traffic volumes is also examined. A method of determining the Level-of Service of two-lane roads in terms...

  7. Safety impacts of rural road construction

    Science.gov (United States)

    2001-02-01

    Crash data in Kentucky show that the fatal crash rate on two-lane rural roads is substantially higher than on any other type of road. Improvements have been proposed at some locations on this type of road which involve either upgrading the existing t...

  8. Misuse of speed-bumps on two-lane main rural roads. A generalized practice in Venezuela

    Energy Technology Data Exchange (ETDEWEB)

    Calderas Volcanes, R.J.; Moreno Gonzalez, E.G.

    2016-07-01

    Settlements of uncontrolled population on side of road in Venezuela originate the excessive use of traffic speed reducers to mitigate accidents. Misuse of these speed control devices generate problem of functionality in the two-lane main rural roads which requires to be studied to demonstrate its effect on the capacity and level of service. Although other factors may occur (i.e, environmental problems and health), the disproportionate use of speed-bumps worsens circulation quality by increase of travel time as most sensitive parameter. Where this effect not can be reversed it should be made efforts to mitigate speed using another traffic-calming device. The studied stretches are selected according to particular characteristics such as: urban settlement, isolated speed-bump and its installation in series, including case without speed-bumps which guarantees the proper contrast. Video cameras to detect the travel time of vehicles are used in each road section, it allow the measures of other parameters. The travel time distribution with or without speed-bumps and probability distribution that characterizes vehicle movement in each stretch allows the simulation and modeling with the ARENA software. Travel time allows obtain the speed which, together with the volume of traffic, determines the level of service according to the Highway Capacity Manual criterion. The economic cost of substitute measures versus travel time is evaluated and may be useful in decision-making or implementation of better policies by transport governmental institutions. (Author)

  9. Road Lane Detection by Discriminating Dashed and Solid Road Lanes Using a Visible Light Camera Sensor.

    Science.gov (United States)

    Hoang, Toan Minh; Hong, Hyung Gil; Vokhidov, Husan; Park, Kang Ryoung

    2016-08-18

    With the increasing need for road lane detection used in lane departure warning systems and autonomous vehicles, many studies have been conducted to turn road lane detection into a virtual assistant to improve driving safety and reduce car accidents. Most of the previous research approaches detect the central line of a road lane and not the accurate left and right boundaries of the lane. In addition, they do not discriminate between dashed and solid lanes when detecting the road lanes. However, this discrimination is necessary for the safety of autonomous vehicles and the safety of vehicles driven by human drivers. To overcome these problems, we propose a method for road lane detection that distinguishes between dashed and solid lanes. Experimental results with the Caltech open database showed that our method outperforms conventional methods.

  10. Road Lane Detection by Discriminating Dashed and Solid Road Lanes Using a Visible Light Camera Sensor

    Directory of Open Access Journals (Sweden)

    Toan Minh Hoang

    2016-08-01

    Full Text Available With the increasing need for road lane detection used in lane departure warning systems and autonomous vehicles, many studies have been conducted to turn road lane detection into a virtual assistant to improve driving safety and reduce car accidents. Most of the previous research approaches detect the central line of a road lane and not the accurate left and right boundaries of the lane. In addition, they do not discriminate between dashed and solid lanes when detecting the road lanes. However, this discrimination is necessary for the safety of autonomous vehicles and the safety of vehicles driven by human drivers. To overcome these problems, we propose a method for road lane detection that distinguishes between dashed and solid lanes. Experimental results with the Caltech open database showed that our method outperforms conventional methods.

  11. Analysis of factors associated with traffic injury severity on rural roads in Iran.

    Science.gov (United States)

    Kashani, Ali Tavakoli; Shariat-Mohaymany, Afshin; Ranjbari, Andishe

    2012-01-01

    Iran is a country with one of the highest rates of traffic crash fatality and injury, and seventy percent of these fatalities happen on rural roads. The objective of this study is to identify the significant factors influencing injury severity among drivers involved in crashes on two kinds of major rural roads in Iran: two-lane, two-way roads and freeways. According to the dataset, 213569 drivers were involved in rural road crashes in Iran, over the 3 years from 2006 to 2008. The Classification And Regression Tree method (CART) was applied for 13 independent variables, and one target variable of injury severity with 3 classes of no-injury, injury and fatality. Some of the independent variables were cause of crash, collision type, weather conditions, road surface conditions, driver's age and gender and seat belt usage. The CART model was trained by 70% of these data, and tested with the rest. It was indicated that seat belt use is the most important safety factor for two-lane, two-way rural roads, but on freeways, the importance of this variable is less. Cause of crash, also turned out to be the next most important variable. The results showed that for two-lane, two-way rural roads, "improper overtaking" and "speeding", and for rural freeways, "inattention to traffic ahead", "vehicle defect", and "movement of pedestrians, livestock and unauthorized vehicles on freeways" are the most serious causes of increasing injury severity. The analysis results revealed seat belt use, cause of crash and collision type as the most important variables influencing the injury severity of traffic crashes. To deal with these problems, intensifying police enforcement by means of mobile patrol vehicles, constructing overtaking lanes where necessary, and prohibiting the crossing of pedestrians and livestock and the driving of unauthorized vehicles on freeways are necessary. Moreover, creating a rumble strip on the two edges of roads, and paying attention to the design consistency of

  12. Impacts of wireless charging lanes on travel time and energy consumption in a two-lane road system

    Science.gov (United States)

    He, Jia; Yang, Hai; Huang, Hai-Jun; Tang, Tie-Qiao

    2018-06-01

    In this paper, we propose a method to compare different energy consumption models and design a strategy to study the quantitative effects of wireless charging lane (WCL) on each electric vehicle's (EV's) link travel time. We utilize the modified energy consumption model and strategy to explore electric vehicle's electricity consumption and link travel time in a two-lane system with a WCL. The numerical results show that EVs' charging behavior on WCL will cause the drivers to execute the lane-changing maneuvers frequently and that the WCL has prominent impacts on EV's energy consumption and travel time, i.e., the capacity drops by 8%-17% while the EV's energy consumption increases by 3%-14% in the two-lane road system.

  13. Analysis of factors associated with traffic injury severity on rural roads in Iran

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    Andishe Ranjbari

    2012-01-01

    Full Text Available BACKGROUND: Iran is a country with one of the highest rates of traffic crash fatality and injury, and seventy percent of these fatalities happen on rural roads. The objective of this study is to identify the significant factors influencing injury severity among drivers involved in crashes on two kinds of major rural roads in Iran: two-lane, two-way roads and freeways. METHODS: According to the dataset, 213569 drivers were involved in rural road crashes in Iran, over the 3 years from 2006 to 2008. The Classification And Regression Tree method (CART was applied for 13 independent variables, and one target variable of injury severity with 3 classes of no-injury, injury and fatality. Some of the independent variables were cause of crash, collision type, weather conditions, road surface conditions, driver's age and gender and seat belt usage. The CART model was trained by 70% of these data, and tested with the rest. RESULTS: It was indicated that seat belt use is the most important safety factor for two-lane, two-way rural roads, but on freeways, the importance of this variable is less. Cause of crash, also turned out to be the next most important variable. The results showed that for two-lane, two-way rural roads, "improper overtaking" and "speeding", and for rural freeways, "inattention to traffic ahead", "vehicle defect", and "movement of pedestrians, livestock and unauthorized vehicles on freeways" are the most serious causes of increasing injury severity. CONCLUSIONS: The analysis results revealed seat belt use, cause of crash and collision type as the most important variables influencing the injury severity of traffic crashes. To deal with these problems, intensifying police enforcement by means of mobile patrol vehicles, constructing overtaking lanes where necessary, and prohibiting the crossing of pedestrians and livestock and the driving of unauthorized vehicles on freeways are necessary. Moreover, creating a rumble strip on the two edges of

  14. Dynamic access control for two-direction shared traffic lanes

    NARCIS (Netherlands)

    Ebben, Mark; van der Zee, D.J.; van der Heijden, Matthijs C.

    2001-01-01

    In specific traffic situations, a single lane is available for traffic from two directions. Examples are traffic accidents or road maintenance reducing the number of available lanes on a road or, as we faced in a project on underground freight transportation, construction of a single lane for two

  15. Dynamic access control for two-direction shared traffic lanes

    NARCIS (Netherlands)

    Ebben, M.J.R.; van der Zee, D.J.; van der Heijden, M.C.

    2000-01-01

    In specilic traflic situations, a single lane is available for traiffic from two directions. Examples are traffic accidents or road maintenance reducing thc number of available lanes on a road or, as we faced in a project on underground freight transportation, construction of a slnglc lane for two

  16. Exploring the relationships between drivers' familiarity and two-lane rural road accidents. A multi-level study.

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    Intini, Paolo; Berloco, Nicola; Colonna, Pasquale; Ranieri, Vittorio; Ryeng, Eirin

    2018-02-01

    Previous research has suggested that drivers' route familiarity/unfamiliarity (using different definitions of familiarity), and the interactions between familiar and unfamiliar drivers, may affect both the driving performances and the likelihood of road crashes. The purpose of this study is to provide a contribution in the search for relationships between familiarity and crashes by: 1) introducing a measure of familiarity based on the distance from residence; 2) analyzing a traffic and accident dataset referred to rural two-lane sections of the Norwegian highways E6 and E39; 3) using a multi-level approach, based on different perspectives, from a macro analysis to more detailed levels. In the macro analyses, the accident rates computed for different seasons and for different summer traffic variation rates (used as indicators of the share of familiar drivers in the flow) were performed. At the second level, a logistic regression model was used to explain the familiarity/unfamiliarity of drivers (based on their distance from residence), through variables retrieved from the database. In the last step, an in-depth analysis considering also accident types and dynamics was conducted. In the macro analysis, no differences were found between accident rates in the different conditions. Whereas, as emerged from the detailed analyses, the factors: high traffic volume, low summer traffic variation, autumn/winter, minor intersections/driveways, speed limits accident risk, possibly due to distraction and dangerous behaviors, while the influence of being unfamiliar on the accident proneness has some unclarified aspects. However, crashes to unfamiliar drivers may cluster at sites showing high summer traffic variation and in summer months. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Development of regionalized SPFs for two-lane rural roads in Pennsylvania.

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    Li, Lingyu; Gayah, Vikash V; Donnell, Eric T

    2017-11-01

    The American Association of State Highway and Transportation Officials' Highway Safety Manual (HSM) contains safety performance functions (SPFs) to predict annual crash frequencies for several roadway types. When applying these SPFs in a jurisdiction whose data were not used to develop the SPF, a calibration factor can be applied to adjust the expected crash frequency estimate to statewide or local conditions. Alternatively, the HSM suggests that transportation agencies may develop their own SPFs in lieu of applying the calibration factor to the HSM SPFs. However, the HSM does not provide guidance on the appropriate level of regionalization that should be adopted for either method, even though safety performance may vary considerably within a state. In light of this, the present study considers the development of local or regionalized SPFs for two-lane rural highways within the Commonwealth of Pennsylvania. Three regionalization levels were considered: statewide, engineering district and individual counties. The expected crash frequency for each level of regionalization was compared to the reported crash frequency over an eight-year analysis period. The results indicate that district-level SPFs with county-level adjustment factors provide better predictive accuracy than the development of a statewide SPF or application of the HSM-calibrated SPF. The findings suggest that there are significant differences in safety performance across engineering districts within Pennsylvania. As such, other state transportation agencies developing SPFs or using calibration factors may also consider how variations across jurisdictions will affect predicted crash frequencies. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Lane-Level Road Information Mining from Vehicle GPS Trajectories Based on Naïve Bayesian Classification

    Directory of Open Access Journals (Sweden)

    Luliang Tang

    2015-11-01

    Full Text Available In this paper, we propose a novel approach for mining lane-level road network information from low-precision vehicle GPS trajectories (MLIT, which includes the number and turn rules of traffic lanes based on naïve Bayesian classification. First, the proposed method (MLIT uses an adaptive density optimization method to remove outliers from the raw GPS trajectories based on their space-time distribution and density clustering. Second, MLIT acquires the number of lanes in two steps. The first step establishes a naïve Bayesian classifier according to the trace features of the road plane and road profiles and the real number of lanes, as found in the training samples. The second step confirms the number of lanes using test samples in reference to the naïve Bayesian classifier using the known trace features of test sample. Third, MLIT infers the turn rules of each lane through tracking GPS trajectories. Experiments were conducted using the GPS trajectories of taxis in Wuhan, China. Compared with human-interpreted results, the automatically generated lane-level road network information was demonstrated to be of higher quality in terms of displaying detailed road networks with the number of lanes and turn rules of each lane.

  19. The effects of lane width, shoulder width, and road cross-sectional reallocation on drivers' behavioral adaptations.

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    Mecheri, Sami; Rosey, Florence; Lobjois, Régis

    2017-07-01

    Previous research has shown that lane-width reduction makes drivers operate vehicles closer to the center of the road whereas hard-shoulder widening induces a position farther away from the road's center. The goal of the present driving-simulator study was twofold. First, it was aimed at further investigating the respective effects of lane and shoulder width on in-lane positioning strategies, by examining vehicle distance from the center of the lane. The second aim was to assess the impact on safety of three possible cross-sectional reallocations of the width of the road (i.e., three lane-width reductions with concomitant shoulder widening at a fixed cross-sectional width) as compared to a control road. The results confirmed that lane-width reduction made participants drive closer to the road's center. However, in-lane position was affected differently by lane narrowing, depending on the traffic situation. In the absence of oncoming traffic, lane narrowing gave rise to significant shifts in the car's distance from the lane's center toward the edge line, whereas this distance remained similar across lane widths during traffic periods. When the shoulders were at least 0.50m wide, participants drove farther away from both the road center and the lane center. Road reallocation operations resulted in vehicles positioned farther away from the edge of the road and less swerving behavior, without generating higher driving speeds. Finally, it is argued that road-space reallocation may serve as a good low-cost tool for providing a recovery area for steering errors, without impairing drivers' behavior. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Image processing-based framework for continuous lane recognition in mountainous roads for driver assistance system

    Science.gov (United States)

    Manoharan, Kodeeswari; Daniel, Philemon

    2017-11-01

    This paper presents a robust lane detection technique for roads on hilly terrain. The target of this paper is to utilize image processing strategies to recognize lane lines on structured mountain roads with the help of improved Hough transform. Vision-based approach is used as it performs well in a wide assortment of circumstances by abstracting valuable information contrasted with other sensors. The proposed strategy processes the live video stream, which is a progression of pictures, and concentrates on the position of lane markings in the wake of sending the edges through different channels and legitimate thresholding. The algorithm is tuned for Indian mountainous curved and paved roads. A technique of computation is utilized to discard the disturbing lines other than the credible lane lines and show just the required prevailing lane lines. This technique will consequently discover two lane lines that are nearest to the vehicle in a picture as right on time as could reasonably be expected. Various video sequences on hilly terrain are tested to verify the effectiveness of our method, and it has shown good performance with a detection accuracy of 91.89%.

  1. Road Lane Detection Robust to Shadows Based on a Fuzzy System Using a Visible Light Camera Sensor.

    Science.gov (United States)

    Hoang, Toan Minh; Baek, Na Rae; Cho, Se Woon; Kim, Ki Wan; Park, Kang Ryoung

    2017-10-28

    Recently, autonomous vehicles, particularly self-driving cars, have received significant attention owing to rapid advancements in sensor and computation technologies. In addition to traffic sign recognition, road lane detection is one of the most important factors used in lane departure warning systems and autonomous vehicles for maintaining the safety of semi-autonomous and fully autonomous systems. Unlike traffic signs, road lanes are easily damaged by both internal and external factors such as road quality, occlusion (traffic on the road), weather conditions, and illumination (shadows from objects such as cars, trees, and buildings). Obtaining clear road lane markings for recognition processing is a difficult challenge. Therefore, we propose a method to overcome various illumination problems, particularly severe shadows, by using fuzzy system and line segment detector algorithms to obtain better results for detecting road lanes by a visible light camera sensor. Experimental results from three open databases, Caltech dataset, Santiago Lanes dataset (SLD), and Road Marking dataset, showed that our method outperformed conventional lane detection methods.

  2. Road Lane Detection Robust to Shadows Based on a Fuzzy System Using a Visible Light Camera Sensor

    Directory of Open Access Journals (Sweden)

    Toan Minh Hoang

    2017-10-01

    Full Text Available Recently, autonomous vehicles, particularly self-driving cars, have received significant attention owing to rapid advancements in sensor and computation technologies. In addition to traffic sign recognition, road lane detection is one of the most important factors used in lane departure warning systems and autonomous vehicles for maintaining the safety of semi-autonomous and fully autonomous systems. Unlike traffic signs, road lanes are easily damaged by both internal and external factors such as road quality, occlusion (traffic on the road, weather conditions, and illumination (shadows from objects such as cars, trees, and buildings. Obtaining clear road lane markings for recognition processing is a difficult challenge. Therefore, we propose a method to overcome various illumination problems, particularly severe shadows, by using fuzzy system and line segment detector algorithms to obtain better results for detecting road lanes by a visible light camera sensor. Experimental results from three open databases, Caltech dataset, Santiago Lanes dataset (SLD, and Road Marking dataset, showed that our method outperformed conventional lane detection methods.

  3. Modeling and simulation of driver's anticipation effect in a two lane system on curved road with slope

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    Kaur, Ramanpreet; Sharma, Sapna

    2018-06-01

    The complexity of traffic flow phenomena on curved road with slope is investigated and a new lattice model is presented with the addition of driver's anticipation effect for two lane system. The condition under which the free flow turns into the jammed one, is obtained theoretically by using stability analysis. The results obtained through linear analysis indicates that the stable region increases (decreases) corresponding to uphill (downhill) case due to increasing slope angle for fixed anticipation parameter. It is found that when the vehicular density becomes higher than a critical value, traffic jam appears in the form of kink antikink density waves. Analytically, the kink antikink density waves are described by the solution of mKdV equation obtained from non linear analysis. In addition, the theoretical results has been verified through numerical simulation, which confirm that the slope on a curved highway significantly influence the traffic dynamics and traffic jam can be suppressed efficiently by considering the anticipation parameter in a two lane lattice model when lane changing is allowed.

  4. Lane changing trajectory planning and tracking control for intelligent vehicle on curved road.

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    Wang, Lukun; Zhao, Xiaoying; Su, Hao; Tang, Gongyou

    2016-01-01

    This paper explores lane changing trajectory planning and tracking control for intelligent vehicle on curved road. A novel arcs trajectory is planned for the desired lane changing trajectory. A kinematic controller and a dynamics controller are designed to implement the trajectory tracking control. Firstly, the kinematic model and dynamics model of intelligent vehicle with non-holonomic constraint are established. Secondly, two constraints of lane changing on curved road in practice (LCCP) are proposed. Thirdly, two arcs with same curvature are constructed for the desired lane changing trajectory. According to the geometrical characteristics of arcs trajectory, equations of desired state can be calculated. Finally, the backstepping method is employed to design a kinematic trajectory tracking controller. Then the sliding-mode dynamics controller is designed to ensure that the motion of the intelligent vehicle can follow the desired velocity generated by kinematic controller. The stability of control system is proved by Lyapunov theory. Computer simulation demonstrates that the desired arcs trajectory and state curves with B-spline optimization can meet the requirements of LCCP constraints and the proposed control schemes can make tracking errors to converge uniformly.

  5. Multivariate poisson lognormal modeling of crashes by type and severity on rural two lane highways.

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    Wang, Kai; Ivan, John N; Ravishanker, Nalini; Jackson, Eric

    2017-02-01

    In an effort to improve traffic safety, there has been considerable interest in estimating crash prediction models and identifying factors contributing to crashes. To account for crash frequency variations among crash types and severities, crash prediction models have been estimated by type and severity. The univariate crash count models have been used by researchers to estimate crashes by crash type or severity, in which the crash counts by type or severity are assumed to be independent of one another and modelled separately. When considering crash types and severities simultaneously, this may neglect the potential correlations between crash counts due to the presence of shared unobserved factors across crash types or severities for a specific roadway intersection or segment, and might lead to biased parameter estimation and reduce model accuracy. The focus on this study is to estimate crashes by both crash type and crash severity using the Integrated Nested Laplace Approximation (INLA) Multivariate Poisson Lognormal (MVPLN) model, and identify the different effects of contributing factors on different crash type and severity counts on rural two-lane highways. The INLA MVPLN model can simultaneously model crash counts by crash type and crash severity by accounting for the potential correlations among them and significantly decreases the computational time compared with a fully Bayesian fitting of the MVPLN model using Markov Chain Monte Carlo (MCMC) method. This paper describes estimation of MVPLN models for three-way stop controlled (3ST) intersections, four-way stop controlled (4ST) intersections, four-way signalized (4SG) intersections, and roadway segments on rural two-lane highways. Annual Average Daily traffic (AADT) and variables describing roadway conditions (including presence of lighting, presence of left-turn/right-turn lane, lane width and shoulder width) were used as predictors. A Univariate Poisson Lognormal (UPLN) was estimated by crash type and

  6. Distinguishing between Rural and Urban Road Segment Traffic Safety Based on Zero-Inflated Negative Binomial Regression Models

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    Xuedong Yan

    2012-01-01

    Full Text Available In this study, the traffic crash rate, total crash frequency, and injury and fatal crash frequency were taken into consideration for distinguishing between rural and urban road segment safety. The GIS-based crash data during four and half years in Pikes Peak Area, US were applied for the analyses. The comparative statistical results show that the crash rates in rural segments are consistently lower than urban segments. Further, the regression results based on Zero-Inflated Negative Binomial (ZINB regression models indicate that the urban areas have a higher crash risk in terms of both total crash frequency and injury and fatal crash frequency, compared to rural areas. Additionally, it is found that crash frequencies increase as traffic volume and segment length increase, though the higher traffic volume lower the likelihood of severe crash occurrence; compared to 2-lane roads, the 4-lane roads have lower crash frequencies but have a higher probability of severe crash occurrence; and better road facilities with higher free flow speed can benefit from high standard design feature thus resulting in a lower total crash frequency, but they cannot mitigate the severe crash risk.

  7. Speed Distribution on Two-Lane Rural Highways with Mixed Traffic: A Case Study in North East India

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    Saha, Pritam; Roy, Nabanita; Sarkar, Ashoke Kumar; Pal, Manish

    2017-06-01

    This work focuses on minimising inaccuracies in distributional assumptions of speed data on two-lane roads with heterogeneous traffic to improve accuracy in capacity and level of service analysis. Accordingly, field study was conducted on a two-lane highway in India that exhibits heterogeneity in its traffic composition. Two distribution functions, namely, normal and logistic were examined for the observed speed data. The appropriate function was chosen using a methodology based on K-S test and field validation. Logistic distribution function was found to exhibit its aptness in describing speed under such traffic and was, thereby, considered in estimating the limiting speed of slower vehicles that tends to obstruct the flow of traffic. Vehicles that move at or below this speed cause delay to the faster ones resulting in formation of platoons at moderate and heavy flow when passing is restricted. Since the percent time-spent-following, a performance measure to assess level-of-service of two-lane highways, considers proportion of vehicles that are trapped inside platoons, it is imperative to estimate the limiting speed of slower vehicles correctly to approximate the delayed vehicles.

  8. Crash prediction model for two-lane rural highways in the Ashanti region of Ghana

    Directory of Open Access Journals (Sweden)

    Williams Ackaah

    2011-07-01

    Full Text Available Crash Prediction Models (CPMs have been used elsewhere as a useful tool by road Engineers and Planners. There is however no study on the prediction of road traffic crashes on rural highways in Ghana. The main objective of the study was to develop a prediction model for road traffic crashes occurring on the rural sections of the highways in the Ashanti Region of Ghana. The model was developed for all injury crashes occurring on selected rural highways in the Region over the three (3 year period 2005–2007. Data was collected from 76 rural highway sections and each section varied between 0.8 km and 6.7 km. Data collected for each section comprised injury crash data, traffic flow and speed data, and roadway characteristics and road geometry data. The Generalised Linear Model (GLM with Negative Binomial (NB error structure was used to estimate the model parameters. Two types of models, the ‘core’ model which included key exposure variables only and the ‘full’ model which included a wider range of variables were developed. The results show that traffic flow, highway segment length, junction density, terrain type and presence of a village settlement within road segments were found to be statistically significant explanatory variables (p<0.05 for crash involvement. Adding one junction to a 1 km section of road segment was found to increase injury crashes by 32.0% and sections which had a village settlement within them were found to increase injury crashes by 60.3% compared with segments with no settlements. The model explained 61.2% of the systematic variation in the data. Road and Traffic Engineers and Planners can apply the crash prediction model as a tool in safety improvement works and in the design of safer roads. It is recommended that to improve safety, highways should be designed to by-pass village settlements and that the number of junctions on a highway should be limited to carefully designed ones.

  9. Lane Departure System Design using with IR Camera for Night-time Road Conditions

    Directory of Open Access Journals (Sweden)

    Osman Onur Akırmak

    2015-02-01

    Full Text Available Today, one of the largest areas of research and development in the automobile industry is road safety. Many deaths and injuries occur every year on public roads from accidents caused by sleepy drivers, that technology could have been used to prevent. Lane detection at night-time is an important issue in driving assistance systems. This paper deals with vision-based lane detection and tracking at night-time. This project consists of a research and development of an algorithm for automotive systems to detect the departure of vehicle from out of lane. Once the situation is detected, a warning is issued to the driver with sound and visual message through “Head Up Display” (HUD system. The lane departure is detected through the images obtained from a single IR camera, which identifies the departure at a satisfactory accuracy via improved quality of video stream. Our experimental results and accuracy evaluation show that our algorithm has good precision and our detecting method is suitable for night-time road conditions.

  10. Lane Changing Trajectory Planning and Tracking Controller Design for Intelligent Vehicle Running on Curved Road

    Directory of Open Access Journals (Sweden)

    Lie Guo

    2014-01-01

    Full Text Available To enhance the active safety and realize the autonomy of intelligent vehicle on highway curved road, a lane changing trajectory is planned and tracked for lane changing maneuver on curved road. The kinematics model of the intelligent vehicle with nonholonomic constraint feature and the tracking error model are established firstly. The longitudinal and lateral coupling and the difference of curvature radius between the outside and inside lane are taken into account, which is helpful to enhance the authenticity of desired lane changing trajectory on curved road. Then the trajectory tracking controller of closed-loop control structure is derived using integral backstepping method to construct a new virtual variable. The Lyapunov theory is applied to analyze the stability of the proposed tracking controller. Simulation results demonstrate that this controller can guarantee the convergences of both the relative position tracking errors and the position tracking synchronization.

  11. Lane assignment traffic control devices on frontage roads and conventional roads at interchanges : technical report.

    Science.gov (United States)

    2011-11-01

    The intersection and mandatory movement lane control signs placed on intersection approaches are critical to : safe and efficient intersection operations. Ramp, frontage road, and cross-street approaches to interchanges : often widen at intersections...

  12. Modelling of lane-changing behaviour integrating with merging effect before a city road bottleneck

    Science.gov (United States)

    Lv, Wei; Song, Wei-guo; Fang, Zhi-ming; Ma, Jian

    2013-10-01

    Merging behaviour is a compulsive action in a discretionary lane-changing traffic system, especially in a system with a bottleneck. This paper aims to investigate the generic lane-changing behaviour considering the merging effect before a city road bottleneck. Thus firstly the merging behaviour is distinguished from other generic lane-changing behaviour. Combining discretionary lane-changing and compulsive merging, we developed an integrative traffic model, in which a method to calculate the lane-changing probability and the merging probability was proposed. A simulation scenario derived from real life was conducted to validate the proposed programming algorithm. Finally, a discussion on the simulation findings shows that the merging influence can be expanded and the merging behaviour can increase the probability of local traffic jamming in its affected area of the adjacent lane. The distribution of the merging distance provides fundamental insights for actual traffic management. The result of the clearance time implies the position of the incident point has a significant effect on the clearing time and it is important to ensure the end (exit) of the road is unimpeded in traffic evacuation.

  13. Road diet informational guide.

    Science.gov (United States)

    2014-11-01

    A classic Road Diet converts an existing four-lane undivided roadway segment to a three-lane segment consisting of two : through lanes and a center two-way left turn lane (TWLTL). A Road Diet improves safety by including a protected left-turn lane : ...

  14. A multiclass vehicular dynamic traffic flow model for main roads and dedicated lanes/roads of multimodal transport network

    Energy Technology Data Exchange (ETDEWEB)

    Sossoe, K.S., E-mail: kwami.sossoe@irt-systemx.fr [TECHNOLOGICAL RESEARCH INSTITUTE SYSTEMX (France); Lebacque, J-P., E-mail: jean-patrick.lebacque@ifsttar.fr [UPE/IFSTTAR-COSYS-GRETTIA (France)

    2015-03-10

    We present in this paper a model of vehicular traffic flow for a multimodal transportation road network. We introduce the notion of class of vehicles to refer to vehicles of different transport modes. Our model describes the traffic on highways (which may contain several lanes) and network transit for pubic transportation. The model is drafted with Eulerian and Lagrangian coordinates and uses a Logit model to describe the traffic assignment of our multiclass vehicular flow description on shared roads. The paper also discusses traffic streams on dedicated lanes for specific class of vehicles with event-based traffic laws. An Euler-Lagrangian-remap scheme is introduced to numerically approximate the model’s flow equations.

  15. New geometric design consistency model based on operating speed profiles for road safety evaluation.

    Science.gov (United States)

    Camacho-Torregrosa, Francisco J; Pérez-Zuriaga, Ana M; Campoy-Ungría, J Manuel; García-García, Alfredo

    2013-12-01

    To assist in the on-going effort to reduce road fatalities as much as possible, this paper presents a new methodology to evaluate road safety in both the design and redesign stages of two-lane rural highways. This methodology is based on the analysis of road geometric design consistency, a value which will be a surrogate measure of the safety level of the two-lane rural road segment. The consistency model presented in this paper is based on the consideration of continuous operating speed profiles. The models used for their construction were obtained by using an innovative GPS-data collection method that is based on continuous operating speed profiles recorded from individual drivers. This new methodology allowed the researchers to observe the actual behavior of drivers and to develop more accurate operating speed models than was previously possible with spot-speed data collection, thereby enabling a more accurate approximation to the real phenomenon and thus a better consistency measurement. Operating speed profiles were built for 33 Spanish two-lane rural road segments, and several consistency measurements based on the global and local operating speed were checked. The final consistency model takes into account not only the global dispersion of the operating speed, but also some indexes that consider both local speed decelerations and speeds over posted speeds as well. For the development of the consistency model, the crash frequency for each study site was considered, which allowed estimating the number of crashes on a road segment by means of the calculation of its geometric design consistency. Consequently, the presented consistency evaluation method is a promising innovative tool that can be used as a surrogate measure to estimate the safety of a road segment. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. Permeability of roads to movement of scrubland lizards and small mammals

    Science.gov (United States)

    Brehme, Cheryl S.; Tracey, Jeff A.; McClenaghan, Leroy R.; Fisher, Robert N.

    2013-01-01

    A primary objective of road ecology is to understand and predict how roads affect connectivity of wildlife populations. Road avoidance behavior can fragment populations, whereas lack of road avoidance can result in high mortality due to wildlife-vehicle collisions. Many small animal species focus their activities to particular microhabitats within their larger habitat. We sought to assess how different types of roads affect the movement of small vertebrates and to explore whether responses to roads may be predictable on the basis of animal life history or microhabitat preferences preferences. We tracked the movements of fluorescently marked animals at 24 sites distributed among 3 road types: low-use dirt, low-use secondary paved, and rural 2-lane highway. Most data we collected were on the San Diego pocket mouse (Chaetodipus fallax), cactus mouse (Peromyscus eremicus), western fence lizard (Sceloporus occidentalis), orange-throated whiptail (Aspidoscelis hyperythra), Dulzura kangaroo rat (Dipodomys simulans) (dirt, secondary paved), and deer mouse (Peromyscus maniculatus) (highway only). San Diego pocket mice and cactus mice moved onto dirt roads but not onto a low-use paved road of similar width or onto the highway, indicating they avoidpaved road substrate. Both lizard species moved onto the dirt and secondary paved roads but avoided the rural 2-lane rural highway, indicating they may avoid noise, vibration, or visual disturbance from a steady flow of traffic. Kangaroo rats did not avoid the dirt or secondary paved roads. Overall, dirt and secondary roads were more permeable to species that prefer to forage or bask in open areas of their habitat, rather than under the cover of rocks or shrubs. However, all study species avoided the rural 2-lane highway. Our results suggest that microhabitat use preferences and road substrate help predict species responses to low-use roads,but roads with heavy traffic may deter movement of a much wider range of small animal

  17. Development of lane change aid system; Lane change aid system no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Uemura, H; Yoshida, T; Butsuen, T [Mazda Motor Corp., Hiroshima (Japan); Sakai, N; Nakano, T; Nakamoto, T

    1997-10-01

    We have developed a lane change aid system, which detects vehicles behind in adjacent lanes with CCD images, shows the driver the information of vehicle location with a head-up display, and warns him/her if necessary. By comparing the brightness on two CCD images, distance distribution along several CCD lines is measured. To assure the effective vehicle detection on public roads, we have developed a detection algorithm which distinguishes vehicles and guard-rails by observing the patterns of measured distances. We will show the system configuration, detection logic, and the system evaluation on public road. 5 refs., 12 figs.

  18. Report of concrete pavement evaluation : project 105 C-4181-01 Donahoo Road, Wyandotte County.

    Science.gov (United States)

    2013-12-01

    The physical properties of hardened concrete cores and fresh concrete test results were compared with aggregate : gradation workability differences. The concrete cores were taken from a rural two-lane concrete road in northeastern Kansas : constructe...

  19. An investigation of merging and diverging cars on a multi-lane road using a cellular automation model

    Science.gov (United States)

    Jetto, K.; Ez-Zahraouy, H.; Benyoussef, A.

    2012-11-01

    In this paper, we have investigated two observed situations in a multi-lane road. The first one concerns a fast merging vehicle. The second situation is related to the case of a fast vehicle leaving the fastest lane back into the slowest lane and targeting a specific way out. We are interested in the relaxation time τ, i.e., which is the time that the merging (diverging) vehicle spends before reaching the desired lane. Using analytical treatment and numerical simulations for the NaSch model, we have found two states, namely, the free state in which the merging (diverging) vehicle reaches the desired lane, and the trapped state in which τ diverges. We have established phase diagrams for several values of the braking probability. In the second situation, we have shown that diverging from the fast lane targeting a specific way out is not a simple task. Even if the diverging vehicle is in the free phase, two different states can be distinguished. One is the critical state, in which the diverging car can probably reach the desired way out. The other is the safe state, in which the diverging car can surely reach the desired way out. In order to be in the safe state, we have found that the driver of the diverging car must know the critical distance (below which the way out will be out of his reach) in each lane. Furthermore, this critical distance depends on the density of cars, and it follows an exponential law.

  20. The Relationship between Road Characteristics and Speed Collected from Floating Car Data

    DEFF Research Database (Denmark)

    Andersen, Camilla Sloth; Reinau, Kristian Hegner; Agerholm, Niels

    2016-01-01

    and driver characteristics. The analysis is based on big data on speed and driver characteristics combined with data on road characteristics on 49 secondary rural two-lane roads in Denmark. Data is modelled using multivariate linear regression. The results show a primarily influence from road and shoulder......Speed is of great importance to the safety level of a road. Speed choice is strongly influenced by the road environment and the drivers’ assessment of safe speed level at a specific location. This paper presents an analysis of the relationships between speed and road characteristics and speed...

  1. Lane marking detection based on waveform analysis and CNN

    Science.gov (United States)

    Ye, Yang Yang; Chen, Hou Jin; Hao, Xiao Li

    2017-06-01

    Lane markings detection is a very important part of the ADAS to avoid traffic accidents. In order to obtain accurate lane markings, in this work, a novel and efficient algorithm is proposed, which analyses the waveform generated from the road image after inverse perspective mapping (IPM). The algorithm includes two main stages: the first stage uses an image preprocessing including a CNN to reduce the background and enhance the lane markings. The second stage obtains the waveform of the road image and analyzes the waveform to get lanes. The contribution of this work is that we introduce local and global features of the waveform to detect the lane markings. The results indicate the proposed method is robust in detecting and fitting the lane markings.

  2. Crashes and near-crashes on horizontal curves along rural two-lane highways: Analysis of naturalistic driving data.

    Science.gov (United States)

    Wang, Bo; Hallmark, Shauna; Savolainen, Peter; Dong, Jing

    2017-12-01

    Prior research has shown the probability of a crash occurring on horizontal curves to be significantly higher than on similar tangent segments, and a disproportionally higher number of curve-related crashes occurred in rural areas. Challenges arise when analyzing the safety of horizontal curves due to imprecision in integrating information as to the temporal and spatial characteristics of each crash with specific curves. The second Strategic Highway Research Program(SHRP 2) conducted a large-scale naturalistic driving study (NDS),which provides a unique opportunity to better understand the contributing factors leading to crash or near-crash events. This study utilizes high-resolution behavioral data from the NDS to identify factors associated with 108 safety critical events (i.e., crashes or near-crashes) on rural two-lane curves. A case-control approach is utilized wherein these events are compared to 216 normal, baseline-driving events. The variables examined in this study include driver demographic characteristics, details of the traffic environment and roadway geometry, as well as driver behaviors such as in-vehicle distractions. Logistic regression models are estimated to discern those factors affecting the likelihood of a driver being crash-involved. These factors include high-risk behaviors, such as speeding and visual distractions, as well as curve design elements and other roadway characteristics such as pavement surface conditions. This paper successfully integrated driver behavior, vehicle characteristics, and roadway environments into the same model. Logistic regression model was found to be an effective way to investigate crash risks using naturalistic driving data. This paper revealed a number of contributing factors to crashes on rural two-lane curves, which has important implications in traffic safety policy and curve geometry design. This paper also discussed limitations and lessons learned from working with the SHRP 2 NDS data. It will benefit

  3. Report of concrete pavement evaluation : project 105 C-4181-01 Donahoo Road, Wyandotte County : [technical summary].

    Science.gov (United States)

    2013-12-01

    The physical properties of hardened concrete cores and fresh concrete test results were compared with aggregate gradation workability differences. The concrete cores were taken from a rural two-lane concrete road in northeastern Kansas constructed in...

  4. Permeability of roads to movement of scrubland lizards and small mammals.

    Science.gov (United States)

    Brehme, Cheryl S; Tracey, Jeff A; McClenaghan, Leroy R; Fisher, Robert N

    2013-08-01

    A primary objective of road ecology is to understand and predict how roads affect connectivity of wildlife populations. Road avoidance behavior can fragment populations, whereas lack of road avoidance can result in high mortality due to wildlife-vehicle collisions. Many small animal species focus their activities to particular microhabitats within their larger habitat. We sought to assess how different types of roads affect the movement of small vertebrates and to explore whether responses to roads may be predictable on the basis of animal life history or microhabitat preferences preferences. We tracked the movements of fluorescently marked animals at 24 sites distributed among 3 road types: low-use dirt, low-use secondary paved, and rural 2-lane highway. Most data we collected were on the San Diego pocket mouse (Chaetodipus fallax), cactus mouse (Peromyscus eremicus), western fence lizard (Sceloporus occidentalis), orange-throated whiptail (Aspidoscelis hyperythra), Dulzura kangaroo rat (Dipodomys simulans) (dirt, secondary paved), and deer mouse (Peromyscus maniculatus) (highway only). San Diego pocket mice and cactus mice moved onto dirt roads but not onto a low-use paved road of similar width or onto the highway, indicating they avoid paved road substrate. Both lizard species moved onto the dirt and secondary paved roads but avoided the rural 2-lane rural highway, indicating they may avoid noise, vibration, or visual disturbance from a steady flow of traffic. Kangaroo rats did not avoid the dirt or secondary paved roads. Overall, dirt and secondary roads were more permeable to species that prefer to forage or bask in open areas of their habitat, rather than under the cover of rocks or shrubs. However, all study species avoided the rural 2-lane highway. Our results suggest that microhabitat use preferences and road substrate help predict species responses to low-use roads, but roads with heavy traffic may deter movement of a much wider range of small animal

  5. Is improved lane keeping during cognitive load caused by increased physical arousal or gaze concentration toward the road center?

    Science.gov (United States)

    Li, Penghui; Markkula, Gustav; Li, Yibing; Merat, Natasha

    2018-08-01

    Driver distraction is one of the main causes of motor-vehicle accidents. However, the impact on traffic safety of tasks that impose cognitive (non-visual) distraction remains debated. One particularly intriguing finding is that cognitive load seems to improve lane keeping performance, most often quantified as reduced standard deviation of lateral position (SDLP). The main competing hypotheses, supported by current empirical evidence, suggest that cognitive load improves lane keeping via either increased physical arousal, or higher gaze concentration toward the road center, but views are mixed regarding if, and how, these possible mediators influence lane keeping performance. Hence, a simulator study was conducted, with participants driving on a straight city road section whilst completing a cognitive task at different levels of difficulty. In line with previous studies, cognitive load led to increased physical arousal, higher gaze concentration toward the road center, and higher levels of micro-steering activity, accompanied by improved lane keeping performance. More importantly, during the high cognitive task, both physical arousal and gaze concentration changed earlier in time than micro-steering activity, which in turn changed earlier than lane keeping performance. In addition, our results did not show a significant correlation between gaze concentration and physical arousal on the level of individual task recordings. Based on these findings, various multilevel models for micro-steering activity and lane keeping performance were conducted and compared, and the results suggest that all of the mechanisms proposed by existing hypotheses could be simultaneously involved. In other words, it is suggested that cognitive load leads to: (i) an increase in arousal, causing increased micro-steering activity, which in turn improves lane keeping performance, and (ii) an increase in gaze concentration, causing lane keeping improvement through both (a) further increased micro

  6. Real-Time Lane Detection on Suburban Streets Using Visual Cue Integration

    Directory of Open Access Journals (Sweden)

    Shehan Fernando

    2014-04-01

    Full Text Available The detection of lane boundaries on suburban streets using images obtained from video constitutes a challenging task. This is mainly due to the difficulties associated with estimating the complex geometric structure of lane boundaries, the quality of lane markings as a result of wear, occlusions by traffic, and shadows caused by road-side trees and structures. Most of the existing techniques for lane boundary detection employ a single visual cue and will only work under certain conditions and where there are clear lane markings. Also, better results are achieved when there are no other on-road objects present. This paper extends our previous work and discusses a novel lane boundary detection algorithm specifically addressing the abovementioned issues through the integration of two visual cues. The first visual cue is based on stripe-like features found on lane lines extracted using a two-dimensional symmetric Gabor filter. The second visual cue is based on a texture characteristic determined using the entropy measure of the predefined neighbourhood around a lane boundary line. The visual cues are then integrated using a rule-based classifier which incorporates a modified sequential covering algorithm to improve robustness. To separate lane boundary lines from other similar features, a road mask is generated using road chromaticity values estimated from CIE L*a*b* colour transformation. Extraneous points around lane boundary lines are then removed by an outlier removal procedure based on studentized residuals. The lane boundary lines are then modelled with Bezier spline curves. To validate the algorithm, extensive experimental evaluation was carried out on suburban streets and the results are presented.

  7. Refining Lane-Based Traffic Signal Settings to Satisfy Spatial Lane Length Requirements

    Directory of Open Access Journals (Sweden)

    Yanping Liu

    2017-01-01

    Full Text Available In conventional lane-based signal optimization models, lane markings guiding road users in making turns are optimized with traffic signal settings in a unified framework to maximize the overall intersection capacity or minimize the total delay. The spatial queue requirements of road lanes should be considered to avoid overdesigns of green durations. Point queue system adopted in the conventional lane-based framework causes overflow in practice. Based on the optimization results from the original lane-based designs, a refinement is proposed to enhance the lane-based settings to ensure that spatial holding limits of the approaching traffic lanes are not exceeded. A solution heuristic is developed to modify the green start times, green durations, and cycle length by considering the vehicle queuing patterns and physical holding capacities along the approaching traffic lanes. To show the effectiveness of this traffic signal refinement, a case study of one of the busiest and most complicated intersections in Hong Kong is given for demonstration. A site survey was conducted to collect existing traffic demand patterns and existing traffic signal settings in peak periods. Results show that the proposed refinement method is effective to ensure that all vehicle queue lengths satisfy spatial lane capacity limits, including short lanes, for daily operation.

  8. Multi-lane detection based on multiple vanishing points detection

    Science.gov (United States)

    Li, Chuanxiang; Nie, Yiming; Dai, Bin; Wu, Tao

    2015-03-01

    Lane detection plays a significant role in Advanced Driver Assistance Systems (ADAS) for intelligent vehicles. In this paper we present a multi-lane detection method based on multiple vanishing points detection. A new multi-lane model assumes that a single lane, which has two approximately parallel boundaries, may not parallel to others on road plane. Non-parallel lanes associate with different vanishing points. A biological plausibility model is used to detect multiple vanishing points and fit lane model. Experimental results show that the proposed method can detect both parallel lanes and non-parallel lanes.

  9. Road traffic injury on rural roads in Tanzania: measuring the effectiveness of a road safety program.

    Science.gov (United States)

    Zimmerman, Karen; Jinadasa, Deepani; Maegga, Bertha; Guerrero, Alejandro

    2015-01-01

    Road traffic injuries (RTIs) are a major public health burden, especially in low- and middle-income countries. There is limited data on RTIs in low-volume, rural African settings. This study attempted to survey all individuals living in households within 200 m of two low-volume rural roads in Tanzania and to collect data on RTIs. Local communities and users of the Bago to Talawanda road (intervention site) and Kikaro to Mihuga road (control site) were targeted and received an intensive program of road safety measures tailored using the crash characteristics of the baseline sample. Demographic data on all household members were collected, and those individuals who suffered an RTI in the previous 3 months had comprehensive information collected about the crash characteristics and the socioeconomic impact. The follow-up data collection occurred nine months after the baseline data were collected. The majority of crashes that caused an RTI involved a motorcycle (71%) and the majority of victims were male (82%) with an average age of 27. Injuries to the legs (55%) were most common and the average length of time away from normal activity was 27 (±33) days. RTI incidence at the intervention site increased during the course of the study (incidence before vs. incidence after) and was unchanged in the community control (incidence before vs. incidence after). The incidence of RTIs in the low-volume rural setting is unacceptably high and most commonly associated with motorcycles. The change in incidence is unreliable due to logistic restraints of the project and more research is needed to quantify the impact of various RTI prevention strategies in this setting. This study provides insight into road traffic injuries on low-volume rural roads, areas where very little research has been captured. Additionally, it provides a replicable study design for those interested in collecting similar data on low-volume rural roads.

  10. The “green wave” mode production on the two-lane highways during the construction works time period

    Directory of Open Access Journals (Sweden)

    А. Berezhnoy

    2007-12-01

    Full Text Available In the paper, the problem of a bi-directional “green wave” mode production is considered for the vehicle flows motion on two-lane highways during the conducting of construction works. The solution of the given task allows to develop practical recommendations for the sphere of the construction works management on two-lane roads and country highways, and also to raise traffic control efficiency in the pointed conditions. The comparative analysis of possible traffic regulation modes for the set scheme of road construction works sites and the estimation of their effi ciency is performed, the test of a hypothesis regarding the possibility of a bi-directional “green wave” mode realization is carried out, and calculation of traffic lights signal control phases time is performed.

  11. IRI performance models for recently constructed low and medium-traffic two lane roads of the province of Biscay

    Energy Technology Data Exchange (ETDEWEB)

    Perez Acebo, H.; Gonzalo-Orden, H.

    2016-07-01

    Reliable pavement prediction models are needed for pavement management systems (PMS), as they are a key component to forecast future conditions of the pavement and to prioritize maintenance, rehabilitation and reconstruction strategies. The International Roughness Index (IRI) is the most used parameter worldwide for calibrating pavement roughness and measures reasonably the ride comfort perceived by occupants of passenger cars. The Regional Government of Biscay also collects this value on the road network under its control These surveys are carried out regularly in the XXI century. Several IRI performance models have been proposed by different authors and administrations, varying greatly in their comprehensiveness, the ability to predict performance with accurancy and input data requirements. The aim of this paper is to develop a roughness performance model for Biscay's roads, based on availablbe IRI data, taking into account heavy traffic volume and the age of pavement. Local characteristics as climate conditions and average rainfall are not considered. IRI performance models have been suggested for regional two lane highways with low and medium heavy traffic constructed in the last 20 years in the province of Biscay, with no treatments during their life. They can be applied for flexible pavements, but no logical coherent results have been concluded for semi-rigid pavements. (Author)

  12. Effects of Car Accidents on Three-Lane Traffic Flow

    Directory of Open Access Journals (Sweden)

    Jianzhong Chen

    2014-01-01

    Full Text Available A three-lane traffic flow model is proposed to investigate the effect of car accidents on the traffic flow. The model is an extension of the full velocity difference (FVD model by taking into account the lane changing. The extended lane-changing rules are presented to model the lane-changing behaviour. The cases that the car accidents occupy the exterior or interior lane, the medium lane, and two lanes are studied by numerical simulations. The time-space diagrams and the current diagrams are presented, and the traffic jams are investigated. The results show that the car accident has a different effect on the traffic flow when it occupies different lanes. The car accidents have a more serious effect on the whole road when they occupy two lanes. The larger the density is, the greater the influence on the traffic flow becomes.

  13. Stability of the car-following model on two lanes

    Science.gov (United States)

    Tang, Tie-Qiao; Huang, Hai-Jun; Gao, Zi-You

    2005-12-01

    In the case of two-lane traffic, vehicle drivers always worry about the lane changing actions from neighbor lane. This paper studies the stability of a car-following model on two lanes which incorporates the lateral effects in traffic. The stability condition of the model is obtained by using the linear stability theory. The modified Korteweg-de Vries equation is constructed and solved, and three types of traffic flows in the headway-sensitivity space—stable, metastable, and unstable—are classified. Both analytical and simulation results show that the anxiousness about lane changing from neighbor lane indeed has influence upon people’s driving behavior and the consideration of lateral effects could stabilize the traffic flows on both lanes.

  14. Quantification of Gravel Rural Road Sediment Production

    Science.gov (United States)

    Silliman, B. A.; Myers Toman, E.

    2014-12-01

    Unbound rural roads are thought to be one of the largest anthropogenic sources of sediment reaching stream channels in small watersheds. This sediment deposition can reduce water quality in the streams negatively impacting aquatic habitat as well as impacting municipal drinking water sources. These roads are thought to see an increase in construction and use in southeast Ohio due to the expansion of shale gas development in the region. This study set out to quantify the amount of sediment these rural roads are able to produce. A controlled rain event of 12.7 millimeters of rain over a half hour period was used to drive sediment production over a 0.03 kilometer section of gravel rural road. These 8 segments varied in many characteristics and produced from 2.0 to 8.4 kilograms of sediment per 0.03 kilometers of road with the average production over the 8 segments being 5.5 kilograms of sediment. Sediment production was not strongly correlated with road segment slope but traffic was found to increase sediment production from 1.1 to 3.9 times as much sediment after traffic use. These results will help inform watershed scale sediment budgeting, and inform best management practices for road maintenance and construction. This study also adds to the understanding of the impacts of rural road use and construction associated with the changing land use from agricultural to natural gas extraction.

  15. Automatic speed management systems : great safety potential ? Paper presented at the Fourth European workshop on Recent Developments in Road Safety Research, October 22-23, 1991 at Bundesanstalt für Strassenwesen (BASt) Bergisch Gladbach, Germany.

    NARCIS (Netherlands)

    Oei, H.-l.

    1991-01-01

    A description is given of a speed management project in the Netherlands, carried out and evaluated by SWOV Institute for Road Safety Research. The following hypotheses form the basis of the four experiments conducted on two-lane rural roads with a speed limit of 80 km/h: (1) Drivers will comply to

  16. Contribution to Accident Prediction Models Development for Rural Two-Lane Roads in Serbia

    Directory of Open Access Journals (Sweden)

    Draženko Glavić

    2016-08-01

    Full Text Available Over the last three decades numerous research efforts have been conducted worldwide to determine the relationship between traffic accidents and traffic and road characteristics. So far, the mentioned studies have not been carried out in Serbia and in the region. This paper represents one of the first attempts to develop accident prediction models in Serbia. The paper provides a comprehensive literature review, describes procedures for collection and analysis of the traffic accident data, as well as the methodology used to develop the accident prediction models. The paper presents models obtained by both univariate and multivariate regression analyses. The obtained results are compared to the results of other studies and comparisons are discussed. Finally, the paper presents conclusions and important points for future research. The results of this research can find theoretical as well as practical application.

  17. Safety effects of cross-section design for two-lane roads. Volume 1

    Science.gov (United States)

    1987-10-01

    This study was intended to quantify the benefits and costs resulting from lane widening, shoulder widening, shoulder surfacing, sideslope flattening, and roadside improvements. Detailed traffic, accident, and roadway data were collected on 4,951 mile...

  18. Tool to manage Road Safety Deficiencies and risk of highway crashes

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Maldonado, G.; Baena Ruiz, L.; Garach Morcillo, L.; Oña Lopez, J. de

    2016-07-01

    In order to facilitate the management of the results obtained in the project “Analysis of the relationship between Road Safety Deficiencies, crashes and hazardous sections” financed by Public Works Agency of the Regional Government of Andalusia (AOPJA) and led by the research group TRYSE from University of Granada, a safety management tool has been developed. This application allows safety managers to consult some factors affecting crashes on two-lane rural highways.The main aim of that project was to analyze the influence of some road deficiencies on crashes and hazardous sections in the Complementary Road Network of Andalusia. These deficiencies were defined in a checklist and were identified by a road inspection. Decision Trees (DTs), that are a data mining technique that allows the extraction of Decision Rules (DRs), were used. DRs revealed the relationship between road deficiencies and crashes.The application allows two different analyses. A specific analysis of the Complementary Road Network of Andalusia, in which, particular safety problems can be identified, and the location of roads with those problems can be obtained. A more general analysis in which some characteristics related to road safety can be selected in order to know the combination of factors contributing to traffic crashes. Safety problems are based on data from Complementary Road Network of Andalusia but results can be extrapolated to other rural highways in Spain. (Author)

  19. Excursions out-of-lane versus standard deviation of lateral position as outcome measure of the on-the-road driving test.

    Science.gov (United States)

    Verster, Joris C; Roth, Thomas

    2014-07-01

    The traditional outcome measure of the Dutch on-the-road driving test is the standard deviation of lateral position (SDLP), the weaving of the car. This paper explores whether excursions out-of-lane are a suitable additional outcome measure to index driving impairment. A literature search was conducted to search for driving tests that used both SDLP and excursions out-of-lane as outcome measures. The analyses were limited to studies examining hypnotic drugs because several of these drugs have been shown to produce next-morning sedation. Standard deviation of lateral position was more sensitive in demonstrating driving impairment. In fact, solely relying on excursions out-of-lane as outcome measure incorrectly classifies approximately half of impaired drives as unimpaired. The frequency of excursions out-of-lane is determined by the mean lateral position within the right traffic lane. Defining driving impairment as having a ΔSDLP > 2.4 cm, half of the impaired driving tests (51.2%, 43/84) failed to produce excursions out-of-lane. Alternatively, 20.9% of driving tests with ΔSDLP < 2.4 cm (27/129) had at least one excursion out-of-lane. Excursions out-of-lane are neither a suitable measure to demonstrate driving impairment nor is this measure sufficiently sensitive to differentiate adequately between differences in magnitude of driving impairment. Copyright © 2014 John Wiley & Sons, Ltd.

  20. Effects of Lane Width, Lane Position and Edge Shoulder Width on Driving Behavior in Underground Urban Expressways: A Driving Simulator Study

    Directory of Open Access Journals (Sweden)

    Shuo Liu

    2016-10-01

    Full Text Available This study tested the effects of lane width, lane position and edge shoulder width on driving behavior for a three-lane underground urban expressway. A driving simulator was used with 24 volunteer test subjects. Five lane widths (2.85, 3.00, 3.25, 3.50, and 3.75 m and three shoulder widths (0.50, 0.75, and 1.00 m were studied. Driving speed, lane deviation and subjective perception of driving behavior were collected as performance measures. The results show that lane and shoulder width have significant effects on driving speed. Average driving speed increases from 60.01 km/h in the narrowest lane to 88.05 km/h in the widest lane. While both narrower lanes and shoulders result in reduced speed and lateral lane deviation, the effect of lane width is greater than that of shoulder width. When the lane and shoulder are narrow, drivers in the left or right lane tend to shy away from the tunnel wall, even encroaching into the neighboring middle lane. As the lane or shoulder gets wider, drivers tend to stay in the middle of the lane. An interesting finding is that although few participants acknowledged that lane position had any great bearing on their driving behaviors, the observed driving speed is statistically higher in the left lane than in the other two lanes when the lane width is narrow (in 2.85, 3 and 3.25 m lanes. These findings provided support for amending the current design specifications of urban underground roads, such as the relationship between design speed and lane width, speed limit, and combination form of lanes.

  1. In-Vehicle Dynamic Curve-Speed Warnings at High-Risk Rural Curves

    Science.gov (United States)

    2018-03-01

    Lane-departure crashes at horizontal curves represent a significant portion of fatal crashes on rural Minnesota roads. Because of this, solutions are needed to aid drivers in identifying upcoming curves and inform them of a safe speed at which they s...

  2. Excursions out-of-lane versus standard deviation of lateral position as outcome measure of the on-the-road driving test

    NARCIS (Netherlands)

    Verster, Joris C; Roth, Thomas

    BACKGROUND: The traditional outcome measure of the Dutch on-the-road driving test is the standard deviation of lateral position (SDLP), the weaving of the car. This paper explores whether excursions out-of-lane are a suitable additional outcome measure to index driving impairment. METHODS: A

  3. Risk Factors Associated with Crash Severity on Low-Volume Rural Roads in Denmark

    DEFF Research Database (Denmark)

    Prato, Carlo Giacomo; Rasmussen, Thomas Kjær; Kaplan, Sigal

    2014-01-01

    Safety on low-volume rural roads is drawing attention due to the high fatality and severe injury rates in comparison with high-volume roads and the increasing awareness of sustainable rural development among policy makers. This study analyzes the risk factors associated with crash severity on low......-volume rural roads, including crash characteristics, driver attributes and behavior, vehicle type, road features, environmental conditions, distance from the nearest hospital, and zone rurality degree. The data consist of a set of crashes occurred on low-volume rural roads in Denmark between 2007 and 2011...... advantage in accommodating the ordered-response nature of severity while relaxing the proportional odds assumption. Model estimates and pseudoelasticities show that aggravated crash injury severity is significantly associated with (1) alcohol and failure to wear seatbelts, (2) involvement of vulnerable road...

  4. Marginal effects of rural roads and irrigation canals on woody and ...

    African Journals Online (AJOL)

    TUOYO

    smaller patches by rural roads network with significant edge effects on plant species composition and abundance. In this study .... information and road inventory details. ... field tests of anti-erosion and maintenance techniques on terrene rural ...

  5. Comparative analysis of the performance of One-Way and Two-Way urban road networks

    Science.gov (United States)

    Gheorghe, Carmen

    2017-10-01

    The fact that the number of vehicles is increasing year after year represents a challenge in road traffic management because it is necessary to adjust the road traffic, in order to prevent any incidents, using mostly the same road infrastructure. At this moment one-way road network provides efficient traffic flow for vehicles but it is not ideal for pedestrians. Therefore, a proper solution must be found and applied when and where it is necessary. Replacing one-way road network with two-way road network may be a viable solution especially if in the area is high pedestrian traffic. The paper aims to highlight the influence of both, one-way and two-way urban road networks through an experimental research which was performed by using traffic data collected in the field. Each of the two scenarios analyzed were based on the same traffic data, the same geometrical conditions of the road (lane width, total road segment width, road slopes, total length of the road network) and also the same signaling conditions (signalised intersection or roundabout). The analysis which involves two-way scenario reveals changes in the performance parameters like delay average, stops average, delay stop average and vehicle speed average. Based on the values obtained, it was possible to perform a comparative analysis between the real, one-way, scenario and the theoretical, two-way, scenario.

  6. Towards End-to-End Lane Detection: an Instance Segmentation Approach

    OpenAIRE

    Neven, Davy; De Brabandere, Bert; Georgoulis, Stamatios; Proesmans, Marc; Van Gool, Luc

    2018-01-01

    Modern cars are incorporating an increasing number of driver assist features, among which automatic lane keeping. The latter allows the car to properly position itself within the road lanes, which is also crucial for any subsequent lane departure or trajectory planning decision in fully autonomous cars. Traditional lane detection methods rely on a combination of highly-specialized, hand-crafted features and heuristics, usually followed by post-processing techniques, that are computationally e...

  7. Semantic Information Extraction of Lanes Based on Onboard Camera Videos

    Science.gov (United States)

    Tang, L.; Deng, T.; Ren, C.

    2018-04-01

    In the field of autonomous driving, semantic information of lanes is very important. This paper proposes a method of automatic detection of lanes and extraction of semantic information from onboard camera videos. The proposed method firstly detects the edges of lanes by the grayscale gradient direction, and improves the Probabilistic Hough transform to fit them; then, it uses the vanishing point principle to calculate the lane geometrical position, and uses lane characteristics to extract lane semantic information by the classification of decision trees. In the experiment, 216 road video images captured by a camera mounted onboard a moving vehicle were used to detect lanes and extract lane semantic information. The results show that the proposed method can accurately identify lane semantics from video images.

  8. Perception and Practice of Road Safety among Medical Students, Mansoura, Egypt.

    Science.gov (United States)

    Helal, Randah; El-Khawaga, Ghada; El-Gilany, Abdel-Hady

    2018-01-01

    To assess the knowledge and attitude of medical students towards road safety and to determine their driving behavior and its relation to different related factors. This cross-sectional study involved 480 medical students at Mansoura University, Egypt. A self-administered questionnaire was used to collect student personal data, knowledge about road safety, attitude towards road safety, and driving practices. More than 40% of students experienced an injury in the previous year, mainly as a pedestrian (56%), and 15.2% practiced driving, although only 9.6% had a driving licence. Most of the students had correct road safety knowledge except for awareness that the safe time to read maps is when your vehicle is parked (44%), one should drive in the left lane (29.6%), and one should overtake from the right-hand lane only (25.8%). The majority of the students reported that road traffic injuries can be prevented (89.2%). The mean score of the driving practices of the students ranged from 0.66±1.04 to 2.44±6.28 and rural residents showed significantly higher score regarding errors and lapses. Good road safety knowledge and a favorable, low risk attitude, did not translate into improved road traffic behavior and this highlights the importance of stricter implementation of the existing rules and including road safety in medical education programs.

  9. Mobility and Access for Off-Road Rural Farmers in West-Akim District

    African Journals Online (AJOL)

    Mobility and Access for Off-Road Rural. Farmers in West-Akim District. Esther Yeboah Da11so-Wired11. Abstract. The study is on the rural transportation problem in Ghana and its consequences on the rural people, especially those who live in off road villages (villages that do not have access to regular transportation ...

  10. An extended two-lane car-following model accounting for inter-vehicle communication

    Science.gov (United States)

    Ou, Hui; Tang, Tie-Qiao

    2018-04-01

    In this paper, we develop a novel car-following model with inter-vehicle communication to explore each vehicle's movement in a two-lane traffic system when an incident occurs on a lane. The numerical results show that the proposed model can perfectly describe each vehicle's motion when an incident occurs, i.e., no collision occurs while the classical full velocity difference (FVD) model produces collision on each lane, which shows the proposed model is more reasonable. The above results can help drivers to reasonably adjust their driving behaviors when an incident occurs in a two-lane traffic system.

  11. "Bicycles May Use Full Lane" Signage Communicates U.S. Roadway Rules and Increases Perception of Safety.

    Science.gov (United States)

    Hess, George; Peterson, M Nils

    2015-01-01

    Many global challenges, including obesity, health care costs, and climate change, could be addressed in part by increasing the use of bicycles for transportation. Concern about the safety of bicycling on roadways is frequently cited as a deterrent to increasing bicycle use in the USA. The use of effective signage along roadways might help alleviate these concerns by increasing knowledge about the rights and duties of bicyclists and motorists, ideally reducing crashes. We administered a web-based survey, using Twitter for recruitment, to examine how well three US traffic control devices communicated the message that bicyclists are permitted in the center of the travel lane and do not have to "get out of the way" to allow motorists to pass without changing lanes: "Bicycles May Use Full Lane" and "Share the Road" signage, and Shared Lane Markings on the pavement. Each was compared to an unsigned roadway. We also asked respondents whether it was safe for a bicyclist to occupy the center of the travel lane. "Bicycles May Use Full Lane" signage was the most consistently comprehended device for communicating the message that bicyclists may occupy the travel lane and also increased perceptions of safety. "Share the Road" signage did not increase comprehension or perceptions of safety. Shared Lane Markings fell somewhere between. "Bicycles May Use Full Lane" signage showed notable increases in comprehension among novice bicyclists and private motor vehicle commuters, critical target audiences for efforts to promote bicycling in the USA. Although limited in scope, our survey results are indicative and suggest that Departments of Transportation consider replacing "Share the Road" with "Bicycles May Use Full Lane" signage, possibly combined with Shared Lane Markings, if the intent is to increase awareness of roadway rights and responsibilities. Further evaluation through virtual reality simulations and on-road experiments is merited.

  12. "Bicycles May Use Full Lane" Signage Communicates U.S. Roadway Rules and Increases Perception of Safety.

    Directory of Open Access Journals (Sweden)

    George Hess

    Full Text Available Many global challenges, including obesity, health care costs, and climate change, could be addressed in part by increasing the use of bicycles for transportation. Concern about the safety of bicycling on roadways is frequently cited as a deterrent to increasing bicycle use in the USA. The use of effective signage along roadways might help alleviate these concerns by increasing knowledge about the rights and duties of bicyclists and motorists, ideally reducing crashes. We administered a web-based survey, using Twitter for recruitment, to examine how well three US traffic control devices communicated the message that bicyclists are permitted in the center of the travel lane and do not have to "get out of the way" to allow motorists to pass without changing lanes: "Bicycles May Use Full Lane" and "Share the Road" signage, and Shared Lane Markings on the pavement. Each was compared to an unsigned roadway. We also asked respondents whether it was safe for a bicyclist to occupy the center of the travel lane. "Bicycles May Use Full Lane" signage was the most consistently comprehended device for communicating the message that bicyclists may occupy the travel lane and also increased perceptions of safety. "Share the Road" signage did not increase comprehension or perceptions of safety. Shared Lane Markings fell somewhere between. "Bicycles May Use Full Lane" signage showed notable increases in comprehension among novice bicyclists and private motor vehicle commuters, critical target audiences for efforts to promote bicycling in the USA. Although limited in scope, our survey results are indicative and suggest that Departments of Transportation consider replacing "Share the Road" with "Bicycles May Use Full Lane" signage, possibly combined with Shared Lane Markings, if the intent is to increase awareness of roadway rights and responsibilities. Further evaluation through virtual reality simulations and on-road experiments is merited.

  13. Improving safety on rural local and tribal roads safety toolkit.

    Science.gov (United States)

    2014-08-01

    Rural roadway safety is an important issue for communities throughout the country and presents a challenge for state, local, and Tribal agencies. The Improving Safety on Rural Local and Tribal Roads Safety Toolkit was created to help rural local ...

  14. Detection and recognition of road markings in panoramic images

    Science.gov (United States)

    Li, Cheng; Creusen, Ivo; Hazelhoff, Lykele; de With, Peter H. N.

    2015-03-01

    Detection of road lane markings is attractive for practical applications such as advanced driver assistance systems and road maintenance. This paper proposes a system to detect and recognize road lane markings in panoramic images. The system can be divided into four stages. First, an inverse perspective mapping is applied to the original panoramic image to generate a top-view road view, in which the potential road markings are segmented based on their intensity difference compared to the surrounding pixels. Second, a feature vector of each potential road marking segment is extracted by calculating the Euclidean distance between the center and the boundary at regular angular steps. Third, the shape of each segment is classified using a Support Vector Machine (SVM). Finally, by modeling the lane markings, previous falsely detected segments can be rejected based on their orientation and position relative to the lane markings. Our experiments show that the system is promising and is capable of recognizing 93%, 95% and 91% of striped line segments, blocks and arrows respectively, as well as 94% of the lane markings.

  15. Design of a Multi-layer Lane-Level Map for Vehicle Route Planning

    Directory of Open Access Journals (Sweden)

    Liu Chaoran

    2017-01-01

    Full Text Available With the development of intelligent transportation system, there occurs further demand for high precision localization and route planning, and simultaneously the traditional road-level map fails to meet with this requirement, by which this paper is motivated. In this paper, t he three-layer lane-level map architecture for vehicle path guidance is established, and the mathematical models of road-level layer, intermediate layer and lane-level layer are designed considering efficiency and precision. The geometric model of the lane-level layer of the map is characterized by Cubic Hermite Spline for continuity. A method of generating the lane geometry with fixed and variable control points is proposed, which can effectively ensure the accuracy with limited num ber of control points. In experimental part, a multi-layer map of an intersection is built to validate the map model, and an example of a local map was generated with the lane-level geometry.

  16. Mobility and Access for Off-Road Rural Farmers in West-Akim District

    African Journals Online (AJOL)

    The study is on the rural transportation problem in Ghana and its consequences on the rural people, especially those who live in off road villages (villages that do not have access to regular transportation systems). The study specifically discusses the failure of the existing road transport network to provide sufficient services ...

  17. Extended-Search, Bézier Curve-Based Lane Detection and Reconstruction System for an Intelligent Vehicle

    Directory of Open Access Journals (Sweden)

    Xiaoyun Huang

    2015-09-01

    Full Text Available To improve the real-time performance and detection rate of a Lane Detection and Reconstruction (LDR system, an extended-search-based lane detection method and a Bézier curve-based lane reconstruction algorithm are proposed in this paper. The extended-search-based lane detection method is designed to search boundary blocks from the initial position, in an upwards direction and along the lane, with small search areas including continuous search, discontinuous search and bending search in order to detect different lane boundaries. The Bézier curve-based lane reconstruction algorithm is employed to describe a wide range of lane boundary forms with comparatively simple expressions. In addition, two Bézier curves are adopted to reconstruct the lanes' outer boundaries with large curvature variation. The lane detection and reconstruction algorithm — including initial-blocks' determining, extended search, binarization processing and lane boundaries' fitting in different scenarios — is verified in road tests. The results show that this algorithm is robust against different shadows and illumination variations; the average processing time per frame is 13 ms. Significantly, it presents an 88.6% high-detection rate on curved lanes with large or variable curvatures, where the accident rate is higher than that of straight lanes.

  18. Naturalistic validation of an on-road driving test of older drivers.

    Science.gov (United States)

    Ott, Brian R; Papandonatos, George D; Davis, Jennifer D; Barco, Peggy P

    2012-08-01

    The objective was to compare a standardized road test to naturalistic driving by older people who may have cognitive impairment to define improvements that could potentially enhance the validity of road testing in this population. Road testing has been widely adapted as a tool to assess driving competence of older people who may be at risk for unsafe driving because of dementia; however, the validity of this approach has not been rigorously evaluated. For 2 weeks, 80 older drivers (38 healthy elders and 42 with cognitive impairment) who passed a standardized road test were video recorded in their own vehicles. Using a standardized rating scale, 4 hr of video was rated by a driving instructor. The authors examine weighting of individual road test items to form global impressions and to compare road test and naturalistic driving using factor analyses of these two assessments. The road test score was unidimensional, reflecting a major factor related to awareness of signage and traffic behavior. Naturalistic driving reflected two factors related to lane keeping as well as traffic behavior. Maintenance of proper lane is an important dimension of driving safety that appears to be relatively underemphasized during the highly supervised procedures of the standardized road test. Road testing in this population could be improved by standardized designs that emphasize lane keeping and that include self-directed driving. Additional information should be sought from observers in the community as well as crash evidence when advising older drivers who may be cognitively impaired.

  19. Rural Roads and Local Market Development in Vietnam

    OpenAIRE

    Mu, Ren; van de Walle, Dominique

    2007-01-01

    The authors assess impacts of rural road rehabilitation on market development at the commune level in rural Vietnam and examine the variance of those impacts and the geographic, community, and household factors that explains it. Double difference and matching methods are used to address sources of selection bias in identifying impacts. The results point to significant average impacts on the ...

  20. Municipal consultation key to understanding haul road maintenance agreements for Saskatchewan rural municipalities

    International Nuclear Information System (INIS)

    Leibel, R.E.A.

    1998-01-01

    Current municipal perspectives regarding the oil and gas industry in Saskatchewan were described. Municipal jurisdiction and authority regarding road development and heavy haul road maintenance agreements were defined. Based on actual work experience, collaborative working relationships between the oil and gas industry and the municipal sector is well worth some industry time and effort since it will result in cost savings for the industry. In general, rural municipalities receive very limited tax benefits to recapture the costs of road reconstruction and maintenance caused by heavy industry traffic. Road servicing costs can be recaptured only if companies respect the weight limits, hauling regulations and road bans. On the whole, municipalities in Saskatchewan are favourably disposed towards the oil and gas industry, and have done well in the past to accommodate industry's needs. It is not unreasonable therefore to expect that industry show sensitivity to the impact of its activities on the local municipality, and does its level best to be on good terms with the municipalities through early two-way communication. Text of some relevant acts of the Legislature respecting the powers and authorities of rural municipalities are appended

  1. Lane detection using Randomized Hough Transform

    Science.gov (United States)

    Mongkonyong, Peerawat; Nuthong, Chaiwat; Siddhichai, Supakorn; Yamakita, Masaki

    2018-01-01

    According to the report of the Royal Thai Police between 2006 and 2015, lane changing without consciousness is one of the most accident causes. To solve this problem, many methods are considered. Lane Departure Warning System (LDWS) is considered to be one of the potential solutions. LDWS is a mechanism designed to warn the driver when the vehicle begins to move out of its current lane. LDWS contains many parts including lane boundary detection, driver warning and lane marker tracking. This article focuses on the lane boundary detection part. The proposed lane boundary detection detects the lines of the image from the input video and selects the lane marker of the road surface from those lines. Standard Hough Transform (SHT) and Randomized Hough Transform (RHT) are considered in this article. They are used to extract lines of an image. SHT extracts the lines from all of the edge pixels. RHT extracts only the lines randomly picked by the point pairs from edge pixels. RHT algorithm reduces the time and memory usage when compared with SHT. The increase of the threshold value in RHT will increase the voted limit of the line that has a high possibility to be the lane marker, but it also consumes the time and memory. By comparison between SHT and RHT with the different threshold values, 500 frames of input video from the front car camera will be processed. The accuracy and the computational time of RHT are similar to those of SHT in the result of the comparison.

  2. Análisis del adelantamiento en carreteras convencionales y propuesta de modelos para la mejora del diseño y de la señalización de las mismas.

    OpenAIRE

    Llorca García, Carlos

    2016-01-01

    [EN] On two-lane rural roads, passing maneuvers allow faster vehicles to pass the slower ones, in order to reduce interferences and improve level of service. However, to pass a slower vehicle, it is necessary to occupy the opposing lane, which had a significant impact on road safety and road operations. For this reason, passing is only permitted at certain parts of the road, where, according to geometric design and marking guidelines, there is sufficient passing sight distance. Passing sight ...

  3. Modeling electric bicycle's lane-changing and retrograde behaviors

    Science.gov (United States)

    Tang, Tie-Qiao; Luo, Xiao-Feng; Zhang, Jian; Chen, Liang

    2018-01-01

    Recently, electric bicycle (EB) has been one important traffic tool due to its own merits. However, EB's motion behaviors (especially at a signalized/non-signalized intersection) are more complex than those of vehicle since it always has lane-changing and retrograde behaviors. In this paper, we propose a model to explore EB's lane-changing and retrograde behaviors on a road with a signalized intersection. The numerical results indicate that the proposed model can qualitatively describe each EB's lane-changing and retrograde behaviors near a signalized intersection, and that lane-changing and retrograde behaviors have prominent impacts on the signalized intersection (i.e., prominent jams and congestions occur). The above results show that EB should be controlled as a vehicle, i.e., lane-changing and retrograde behaviors at a signalized intersection should strictly be prohibited to improve the operational efficiency and traffic safety at the signalized intersection.

  4. Studies of vehicle lane-changing dynamics and its effect on traffic efficiency, safety and environmental impact

    Science.gov (United States)

    Li, Xiang; Sun, Jian-Qiao

    2017-02-01

    Drivers often change lanes on the road to maintain desired speed and to avoid slow vehicles, pedestrians, obstacles and lane closure. Understanding the effect of lane-changing on the traffic is an important topic in designing optimal traffic control systems. This paper presents a comprehensive study of this topic. We review the theory of microscopic dynamic car-following models and the lane-changing models, propose additional lane-changing rules to deal with moving bottleneck and lane reduction, and investigate the effects of lane-changing on the traffic efficiency, traffic safety and fuel consumption as a function of different variables including the distance of the emergency sign ahead of the lane closure, speed limit, traffic density, etc. Extensive simulations of the traffic system have been carried out in different scenarios. A number of important findings of the effect of various factors on the traffic are reported. These findings provide guidance on the traffic management and are important to the designers and engineers of modern highway or inner city roads to achieve high traffic efficiency and safety with minimum environmental impact.

  5. Analytical Model for Passing Sight Distance Design Criteria of Two-Lane Roads in Sri Lanka

    Directory of Open Access Journals (Sweden)

    Mampearachchi W. K.

    2018-03-01

    Full Text Available For a safe overtaking manoeuvre on two-lane highways, drivers need a sufficient sight distance along the roadway, but it depends on the traffic environment. To provide an adequate Passing Sight Distance (PSD, a number of models have been proposed since the initial model introduced by American Association of State Highways and Transport Officials (AASHTO in 1954. It is a current design practice in Sri Lanka as well, however, not validated for local traffic conditions. This paper will present an alternative PSD model and an evaluation of AASHTO model for national highway design. Experiment was based on GPS data collection. In conclusion, PSD demand was satisfied by AASHTO PSD under mix traffic conditions, but not the safety concerns for speeds greater than 80 km/h, while alternative model successful for all speeds.

  6. a Novel Approach to Camera Calibration Method for Smart Phones Under Road Environment

    Science.gov (United States)

    Lee, Bijun; Zhou, Jian; Ye, Maosheng; Guo, Yuan

    2016-06-01

    Monocular vision-based lane departure warning system has been increasingly used in advanced driver assistance systems (ADAS). By the use of the lane mark detection and identification, we proposed an automatic and efficient camera calibration method for smart phones. At first, we can detect the lane marker feature in a perspective space and calculate edges of lane markers in image sequences. Second, because of the width of lane marker and road lane is fixed under the standard structural road environment, we can automatically build a transformation matrix between perspective space and 3D space and get a local map in vehicle coordinate system. In order to verify the validity of this method, we installed a smart phone in the `Tuzhi' self-driving car of Wuhan University and recorded more than 100km image data on the road in Wuhan. According to the result, we can calculate the positions of lane markers which are accurate enough for the self-driving car to run smoothly on the road.

  7. Naturalistic Validation of an On-Road Driving Test of Older Drivers

    Science.gov (United States)

    Ott, Brian R.; Papandonatos, George D.; Davis, Jennifer D.; Barco, Peggy P.

    2013-01-01

    Objective The objective was to compare a standardized road test to naturalistic driving by older people who may have cognitive impairment to define improvements that could potentially enhance the validity of road testing in this population. Background Road testing has been widely adapted as a tool to assess driving competence of older people who may be at risk for unsafe driving because of dementia; however, the validity of this approach has not been rigorously evaluated. Method For 2 weeks, 80 older drivers (38 healthy elders and 42 with cognitive impairment) who passed a standardized road test were video recorded in their own vehicles. Using a standardized rating scale, 4 hr of video was rated by a driving instructor. The authors examine weighting of individual road test items to form global impressions and to compare road test and naturalistic driving using factor analyses of these two assessments. Results The road test score was unidimensional, reflecting a major factor related to awareness of signage and traffic behavior. Naturalistic driving reflected two factors related to lane keeping as well as traffic behavior. Conclusion Maintenance of proper lane is an important dimension of driving safety that appears to be relatively underemphasized during the highly supervised procedures of the standardized road test. Application Road testing in this population could be improved by standardized designs that emphasize lane keeping and that include self-directed driving. Additional information should be sought from observers in the community as well as crash evidence when advising older drivers who may be cognitively impaired. PMID:22908688

  8. Cost, performance, and esthetic impacts of an experimental forest road in Montana

    Science.gov (United States)

    Rulon B. Gardner

    1978-01-01

    An experimental logging road designed to minimize environmental and esthetic impact was constructed in northwest Montana. The road was single-lane (14-foot finished surface, 3-foot ditch), constructed along the contour. Esthetically, the single-lane experimental road was judged far superior to existing roads on the forest.

  9. Analysis of optimum density of forest roads in rural properties

    Directory of Open Access Journals (Sweden)

    Flávio Cipriano de Assis do Carmo

    2013-09-01

    Full Text Available This study analyzed the density of roads in rural properties in the south of the Espírito Santo and compared it with the calculation of the optimal density in forestry companies in steep areas. The work was carried out in six small rural properties based on the costs of roads of forest use, wood extraction and the costs of loss of productive area. The technical analysis included time and movement study and productivity. The economic analysis included operational costs, production costs and returns for different scenarios of productivity (180m.ha-1, 220m.ha-1and 250 m.ha-1. According to the results, all the properties have densities of road well above the optimum, which reflects the lack of criteria in the planning of the forest stands, resulting in a inadequate use of plantation area. Property 1 had the highest density of roads (373.92 m.ha-1 and the property 5 presented the lowest density (111.56 m.ha-1.

  10. Trauma on rural roads: the role of a peripheral hospital.

    LENUS (Irish Health Repository)

    Street, J T

    2012-02-03

    Road accident trauma is a leading cause of death and serious morbidity among healthy young adults in the developed world. The Irish Republic has the third worst road safety record in the EU. In studying the unique demographics of rural road accidents, our aim was to provide information essential to the future development of trauma care in Ireland. Our figures highlight the inadequacies of data received by the National Roads Authority, illustrate the resource impact of road trauma on a peripheral hospital, and demonstrate the need for similar studies in the rationalisation of trauma care as we approach the next millennium.

  11. Improving the Lane Reference Detection for Autonomous Road Vehicle Control

    Directory of Open Access Journals (Sweden)

    Felipe Jiménez

    2016-01-01

    Full Text Available Autonomous road vehicles are increasingly becoming more important and there are several techniques and sensors that are being applied for vehicle control. This paper presents an alternative system for maintaining the position of autonomous vehicles without adding additional elements to the standard sensor architecture, by using a 3D laser scanner for continuously detecting a reference element in situations in which the GNSS receiver fails or provides accuracy below the required level. Considering that the guidance variables are more accurately estimated when dealing with reference points in front of and behind the vehicle, an algorithm based on vehicle dynamics mathematical model is proposed to extend the detected points in cases where the sensor is placed at the front of the vehicle. The algorithm has been tested when driving along a lane delimited by New Jersey barriers at both sides and the results show a correct behaviour. The system is capable of estimating the reference element behind the vehicle with sufficient accuracy when the laser scanner is placed at the front of it, so the robustness of the control input variables (lateral and angular errors estimation is improved making it unnecessary to place the sensor on the vehicle roof or to introduce additional sensors.

  12. A new shared control for lane keeping and road departure prevention

    Science.gov (United States)

    Merah, Abdelkader; Hartani, Kada; Draou, Azeddine

    2016-01-01

    In recent years, the driver's active assistances have become important features in commercialised vehicles. In this paper, we present one of these features which consists of an advanced driver assistance system for lane keeping. A thorough analysis of its performance and stability with respect to variations in driver behaviour will be given. Firstly, the lateral control model based on visual preview is established and the kinematics model based on visual preview, including speed and other factors, is used to calculate the lateral error and direction error. Secondly, and according to the characteristics of the lateral control, an efficient strategy of intelligent electric vehicle lateral mode is proposed. The integration of the vehicle current lateral error and direction error is chosen as the parameter of the sliding mode switching function to design the sliding surface. The control variables are adjusted according to the fuzzy control rules to ensure that they meet the existence and reaching condition. A new fuzzy logic-based switching strategy with an efficient control law is also proposed to ensure a level of continuous and variable sharing according to the state of the driver and the vehicle positioning on the roadway. The proposed control law acts either at the centre of the lane, as a lane keeping assistance system to reduce the driver's workload for long trips, or as a lane departure avoidance system that intervenes for unintended lane departures. Simulation results are included in this paper to explain this concept.

  13. A good road lies easy on the land: Water harvesting from low-standard rural roads

    OpenAIRE

    Zeedyk, B.

    2006-01-01

    Metadata only record This book addresses the construction and maintenance of unpaved rural roads including strategies, techniques and practices for dealing with problems frequently encountered by landowners, land managers and maintenance personnel. Running water is the primary force affecting road condition and generating the need for maintenance. Economical maintenance means dealing effectively with water, but not just surface runoff. Standing water, seeping water, rain, snow, ice, frost ...

  14. Risk Factors for Road Transport-Related Injury among Pedestrians in Rural Ghana: Implications for Road Safety Education

    Science.gov (United States)

    Teye-Kwadjo, Enoch

    2017-01-01

    Objectives: Injuries and mortality resulting from pedestrian road traffic crashes are a major public health problem in Ghana. This study investigated risk factors for road transport-related injury among pedestrians in rural Ghana. Design: Case study design using qualitative data. Method: In-depth interviews were conducted with pedestrians.…

  15. Alternatives to conventional gravel wearing courses on low volume rural roads: Phase 1

    CSIR Research Space (South Africa)

    Paige-Green, P

    2003-01-01

    Full Text Available Adviser Abstract Gundo Lashu, the ‘Labour Intensive Rural Roads Maintenance Programme’ that is currently being implemented in Limpopo Province, South Africa has set out to train 24 emerging contractors in rehabilitation of rural gravel roads. All.... The proposal is to treat the in situ materials and sand with a diluted emulsion and a nominal cement application (to assist with breaking of the emulsion) and surface the road with an Otta seal. The aggregate for the Otta seal can be obtained form...

  16. Sensitivity Analysis Based SVM Application on Automatic Incident Detection of Rural Road in China

    Directory of Open Access Journals (Sweden)

    Xingliang Liu

    2018-01-01

    Full Text Available Traditional automatic incident detection methods such as artificial neural networks, backpropagation neural network, and Markov chains are not suitable for addressing the incident detection problem of rural roads in China which have a relatively high accident rate and a low reaction speed caused by the character of small traffic volume. This study applies the support vector machine (SVM and parameter sensitivity analysis methods to build an accident detection algorithm in a rural road condition, based on real-time data collected in a field experiment. The sensitivity of four parameters (speed, front distance, vehicle group time interval, and free driving ratio is analyzed, and the data sets of two parameters with a significant sensitivity are chosen to form the traffic state feature vector. The SVM and k-fold cross validation (K-CV methods are used to build the accident detection algorithm, which shows an excellent performance in detection accuracy (98.15% of the training data set and 87.5% of the testing data set. Therefore, the problem of low incident reaction speed of rural roads in China could be solved to some extent.

  17. A NOVEL APPROACH TO CAMERA CALIBRATION METHOD FOR SMART PHONES UNDER ROAD ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    B. Lee

    2016-06-01

    Full Text Available Monocular vision-based lane departure warning system has been increasingly used in advanced driver assistance systems (ADAS. By the use of the lane mark detection and identification, we proposed an automatic and efficient camera calibration method for smart phones. At first, we can detect the lane marker feature in a perspective space and calculate edges of lane markers in image sequences. Second, because of the width of lane marker and road lane is fixed under the standard structural road environment, we can automatically build a transformation matrix between perspective space and 3D space and get a local map in vehicle coordinate system. In order to verify the validity of this method, we installed a smart phone in the ‘Tuzhi’ self-driving car of Wuhan University and recorded more than 100km image data on the road in Wuhan. According to the result, we can calculate the positions of lane markers which are accurate enough for the self-driving car to run smoothly on the road.

  18. Visibility of road markings on wet road surfaces : a literature study.

    NARCIS (Netherlands)

    Schreuder, D.A.

    1981-01-01

    The English version of B 14153 is presented. Road markings, notably lane markers, are often only poorly visible when the road is wet. This is particularly a problem at night on unlit roads. A study is made of whether a solution for this problem can be found on the basis of the known, published

  19. The changes of densities and patterns of roads and rural buildings: a case study on Dongzhi Yuan of the Loess Plateau, China.

    Science.gov (United States)

    Bi, Xiaoli; Wang, Hui; Ge, Jianping

    2010-05-01

    Roads and buildings are considered as primary causes of rural landscape changes. In this study, linear regression models were used to analyze the dynamic influences of environmental factors and variables on roads and rural buildings from 1979 to 2005 in Dongzhi Yuan (tableland) of the Loess Plateau, China. The relationship between roads and rural buildings and their effects on Dongzhi Yuan are discussed also. The results showed that three environmental factors (topography, land cover, and development level) explained roads better than rural buildings referring densities and patterns. The environmental variables significantly related to roads have decreased, whereas those related to rural buildings have increased over time. Among these significant variables, percent of farmland mostly determined the densities and patterns of both roads and rural buildings. There was significant correlation between roads and rural buildings in terms of density and pattern. In addition, roads and rural buildings have increased greatly in gully areas of this region. Therefore, more attention should be paid to planning of roads and rural buildings in Dongzhi Yuan.

  20. Highway driving safety the day after using sleep medication: the direction of lapses and excursions out-of-lane in drowsy drivers.

    Science.gov (United States)

    Verster, Joris C; Mooren, Loes; Bervoets, Adriana C; Roth, Thomas

    2017-10-24

    The primary outcome measure of the on-road driving test is the Standard Deviation of Lateral Position. However, other outcome measures, such as lapses and excursions out-of-lane, also need to be considered as they may be related to crash risk. The aim of this study was to determine the direction of lapses and excursions out-of-lane (i.e. towards/into the adjacent traffic lane or towards/into the road shoulder). In total, data from 240 driving tests were re-analysed, and 628 lapses and 401 excursions out-of-lane were identified. The analyses revealed that lapses were made equally frequently over left (49.4%) and over right (43.3%). In contrast, excursions out-of-lane were almost exclusively directed over right into the (safer) road shoulder (97.3%). These findings suggest that drivers are unaware of having lapses, whereas excursions out-of-lane are events where the driver is aware of loss of vehicle control. © 2017 The Authors. Journal of Sleep Research published by John Wiley & Sons Ltd on behalf of European Sleep Research Society.

  1. Human factors study of driver assistance systems to reduce lane departures and side collision accidents.

    Science.gov (United States)

    2008-07-01

    This study investigated the human factors issues related to the implementation of lane departure warning systems (LDWS) to reduce side collision and run-off-road crashes for heavy trucks. Lane departures can be either intentional (e.g., to pass anoth...

  2. Bifurcation of Lane Change and Control on Highway for Tractor-Semitrailer under Rainy Weather

    Directory of Open Access Journals (Sweden)

    Tao Peng

    2017-01-01

    Full Text Available A new method is proposed for analyzing the nonlinear dynamics and stability in lane changes on highways for tractor-semitrailer under rainy weather. Unlike most of the literature associated with a simulated linear dynamic model for tractor-semitrailers steady steering on dry road, a verified 5DOF mechanical model with nonlinear tire based on vehicle test was used in the lane change simulation on low adhesion coefficient road. According to Jacobian matrix eigenvalues of the vehicle model, bifurcations of steady steering and sinusoidal steering on highways under rainy weather were investigated using a numerical method. Furthermore, based on feedback linearization theory, taking the tractor yaw rate and joint angle as control objects, a feedback linearization controller combined with AFS and DYC was established. The numerical simulation results reveal that Hopf bifurcations are identified in steady and sinusoidal steering conditions, which translate into an oscillatory behavior leading to instability. And simulations of urgent step and single-lane change in high velocity show that the designed controller has good effects on eliminating bifurcations and improving lateral stability of tractor-semitrailer, during lane changing on highway under rainy weather. It is a valuable reference for safety design of tractor-semitrailers to improve the traffic safety with driver-vehicle-road closed-loop system.

  3. The economics of potential reduction of the rural road system in Kansas.

    Science.gov (United States)

    2011-11-01

    Benefitcost analysis was used to examine the question of road closure in the three counties. The cost of road : closure is the additional travel cost of rural residents due to more circuitous routing to their destinations. The benefit is : the avo...

  4. Risk assessment of metals in road-deposited sediment along an urban–rural gradient

    International Nuclear Information System (INIS)

    Zhao, Hongtao; Li, Xuyong

    2013-01-01

    We applied the traditional risk assessment methods originally designed for soils and river sediments to evaluation of risk associated with metals in road-deposited sediment (RDS) along an urban–rural gradient that included central urban (UCA), urban village (UVA), central suburban county (CSA), rural town (RTA), and rural village (RVA) areas in the Beijing metropolitan region. A new indicator RI RDS was developed which integrated the RDS characteristics of mobility, grain size and amount with the potential ecological risk index. The risk associated with metals in RDS in urban areas was generally higher than that in rural areas based on the assessment using traditional methods, but the risk was higher in urban and rural village areas than the areas with higher administration units based on the indicator RI RDS . These findings implied that RDS characteristics variation with the urban–rural gradient must be considered in metal risk assessment and RDS washoff pollution control. Highlights: ► Spatial pattern of metal risk level associated with road-deposited sediment (RDS) along urban–rural gradients varied. ► Risk level of metals changed significantly when grain size was considered. ► A new index integrating RDS characteristics and potential ecological risk was developed. ► Results from the new index were improved relative to those of traditional assessment methods. -- A new index integrating road-deposited sediment characteristics and potential ecological risk was developed to assess metal risk along the urban–rural gradient

  5. Using endemic road features to create self-explaining roads and reduce vehicle speeds.

    Science.gov (United States)

    Charlton, Samuel G; Mackie, Hamish W; Baas, Peter H; Hay, Karen; Menezes, Miguel; Dixon, Claire

    2010-11-01

    This paper describes a project undertaken to establish a self-explaining roads (SER) design programme on existing streets in an urban area. The methodology focussed on developing a process to identify functional road categories and designs based on endemic road characteristics taken from functional exemplars in the study area. The study area was divided into two sections, one to receive SER treatments designed to maximise visual differences between road categories, and a matched control area to remain untreated for purposes of comparison. The SER design for local roads included increased landscaping and community islands to limit forward visibility, and removal of road markings to create a visually distinct road environment. In comparison, roads categorised as collectors received increased delineation, addition of cycle lanes, and improved amenity for pedestrians. Speed data collected 3 months after implementation showed a significant reduction in vehicle speeds on local roads and increased homogeneity of speeds on both local and collector roads. The objective speed data, combined with residents' speed choice ratings, indicated that the project was successful in creating two discriminably different road categories. 2010 Elsevier Ltd. All rights reserved.

  6. Rural roadway safety perceptions among rural teen drivers living in and outside of towns.

    Science.gov (United States)

    Ramirez, Marizen; Roth, Lisa; Young, Tracy; Peek-Asa, Corinne

    2013-01-01

    To compare perceptions about rural road and general driving behaviors between teens who live in- and out-of-town from rural communities in Iowa. A cross-sectional survey was conducted with 160 teens anticipating their Intermediate License within 3 months upon enrollment into this study. Self-administered surveys were used to collect demographics and driving exposures (eg, frequency of driving, age when first drove unsupervised). Two Likert scales were included to measure agreement with safe driving behaviors on rural roads and general safe driving behaviors (eg, speeding, seat belt use). T-tests were calculated comparing mean composite scores between in- and out-of-town teens, and between mean rural road and general driving safety attitude scores. A linear regression multivariable model was constructed to identify predictors of the rural road score. While the majority of teens endorsed rural road and general safe driving behaviors, up to 40% did not. Thirty-two percent did not believe the dangers of animals on rural roads, and 40% disagreed that exceeding the speed limit is dangerous. In-town teens were less safety conscious about rural road hazards with a significantly lower mean composite score (4.4) than out-of-town teens (4.6); mean scores for general driving behaviors were similar. Living out-of-town and owning one's own car were significant predictors of increased rural road safety scores. Rural, in-town teens have poorer safety attitudes about rural roadway hazards compared with out-of-town teens. Interventions that involve education, parental supervision, and practice on rural roads are critical for preventing teen crashes on rural roads. No claim to original US government works.

  7. Engineering Solutions to Enhance Traffic Safety Performance on Two-Lane Highways

    Directory of Open Access Journals (Sweden)

    Lina Wu

    2015-01-01

    Full Text Available Improving two-lane highway traffic safety conditions is of practical importance to the traffic system, which has attracted significant research attention within the last decade. Many cost-effective and proactive solutions such as low-cost treatments and roadway safety monitoring programs have been developed to enhance traffic safety performance under prevailing conditions. This study presents research perspectives achieved from the Highway Safety Enhancement Project (HSEP that assessed safety performance on two-lane highways in Beijing, China. Potential causal factors are identified based on proposed evaluation criteria, and primary countermeasures are developed against inferior driving conditions such as sharp curves, heavy gradients, continuous downgrades, poor sight distance, and poor clear zones. Six cost-effective engineering solutions were specifically implemented to improve two-lane highway safety conditions, including (1 traffic sign replacement, (2 repainting pavement markings, (3 roadside barrier installation, (4 intersection channelization, (5 drainage optimization, and (6 sight distance improvement. The effectiveness of these solutions was examined and evaluated based on Empirical Bayes (EB models. The results indicate that the proposed engineering solutions effectively improved traffic safety performance by significantly reducing crash occurrence risks and crash severities.

  8. Weighted Poisson analyses à la Goodman using SAS-GENMOD. [Paper presented at 15th SAS European Users Group International SEUGI Conference, Madrid, 12-16 May 1997].

    NARCIS (Netherlands)

    Vogelesang, A.W.

    2010-01-01

    In traffic safety analysis, weight factors are often applied, to correct for road length, traffic volume, numbers of kilometers driven, etc. Also, many data are subdivided into classes (road type: freeway, 80 km/hr, two lanes, rural area, etc); combining factors often leads to a

  9. Enrichment and sources of trace metals in roadside soils in Shanghai, China: A case study of two urban/rural roads.

    Science.gov (United States)

    Yan, Geng; Mao, Lingchen; Liu, Shuoxun; Mao, Yu; Ye, Hua; Huang, Tianshu; Li, Feipeng; Chen, Ling

    2018-08-01

    The road traffic has become one of the main sources of urban pollution and could directly affect roadside soils. To understand the level of contamination and potential sources of trace metals in roadside soils of Shanghai, 10 trace metals (Sb, Cr, Co, Ni, Cu, Cd, Pb, Hg, Mn and Zn) from two urban/rural roads (Hutai Road and Wunign-Caoan Road) were analyzed in this study. Antimony, Ni, Cu, Cd, Pb, Hg and Zn concentrations were higher than that of soil background values of Shanghai, whereas accumulation of Cr, Co and Mn were minimal. Significantly higher Sb, Cd, Pb contents were found in samples from urban areas than those from suburban area, suggesting the impact from urbanization. The concentrations of Sb and Cd in older road (Hutai) were higher than that in younger road (Wunign-Caoan). Multivariate statistical analysis revealed that Sb, Cu, Cd, Pb and Zn were mainly controlled by traffic activities (e.g. brake wear, tire wear, automobile exhaust) with high contamination levels found near traffic-intensive areas; Cr, Co, Ni and Mn derived primarily from soil parent materials; Hg was related to industrial activities. Besides, the enrichment of Sb, Cd, Cu, Pb and Zn showed a decreasing trend with distance to the road edges. According to the enrichment factors (EF s ), 78.5% of Sb, Cu, Cd, Pb and Zn were in moderate or significant pollution, indicating considerable traffic contribution. In particular, recently introduced in automotive technology, accumulation of Sb has been recognized in 42.9% samples of both roads. The accumulation of these traffic-derived metals causes potential negative impact to human health and ecological environment and should be concerned, especially the emerging trace elements like Sb. Copyright © 2018 Elsevier B.V. All rights reserved.

  10. Establecimiento de parámetros de riesgo para la seguridad de los ciclistas durante las maniobras de adelantamiento en carreteras convencionales

    OpenAIRE

    Ferrer Pérez, Vicente Melchor

    2017-01-01

    Concerning road safety, overtaking to cyclists is one of the most dangerous maneuvers that appear in two-lane rural roads, for both motor vehicles and cyclists. The underlying cause is that vehicles must partially invade the opposite lane, while driving parallel to them. Cyclists are very vulnerable users, thus being under a situation of clear inferiority with the rest of vehicles. In addition, the maneuver entirely depends on drivers, involving many variables in a complex decision process to...

  11. Sensor fusion: lane marking detection and autonomous intelligent cruise control system

    Science.gov (United States)

    Baret, Marc; Baillarin, S.; Calesse, C.; Martin, Lionel

    1995-12-01

    In the past few years MATRA and RENAULT have developed an Autonomous Intelligent Cruise Control (AICC) system based on a LIDAR sensor. This sensor incorporating a charge coupled device was designed to acquire pulsed laser diode emission reflected by standard car reflectors. The absence of moving mechanical parts, the large field of view, the high measurement rate and the very good accuracy for distance range and angular position of targets make this sensor very interesting. It provides the equipped car with the distance and the relative speed of other vehicles enabling the safety distance to be controlled by acting on the throttle and the automatic gear box. Experiments in various real traffic situations have shown the limitations of this kind of system especially on bends. All AICC sensors are unable to distinguish between a bend and a change of lane. This is easily understood if we consider a road without lane markings. This fact has led MATRA to improve its AICC system by providing the lane marking information. Also in the scope of the EUREKA PROMETHEUS project, MATRA and RENAULT have developed a lane keeping system in order to warn of the drivers lack of vigilance. Thus, MATRA have spread this system to far field lane marking detection and have coupled it with the AICC system. Experiments will be carried out on roads to estimate the gain in performance and comfort due to this fusion.

  12. Marginal effects of rural roads and irrigation canals on woody and ...

    African Journals Online (AJOL)

    Across the northern rural regions of Iran, gardens and farmlands are being fragmented into smaller and smaller patches by rural roads network with significant edge effects on plant species composition and abundance. In this study, the presence of different plant species was recorded in ninety 1´1 m plots on nine 100 m ...

  13. First motorcycle-exclusive lane (Motovia) in Colombia: perceptions of users in Cali, 2012-2013.

    Science.gov (United States)

    Osorio-Cuéllar, Gisel V; Pacichana-Quinayaz, Sara G; Bonilla-Escobar, Francisco J; Fandiño-Losada, Andrés; Jaramillo-Molina, Ciro; Gutiérrez-Martínez, María I

    2017-06-01

    This study's goal was to evaluate the pilot exclusive lane for motorcycles (Motovía) in Cali, Colombia, from the perception of its users in 2012-2013. A cross-sectional study using roadside surveys plus a qualitative component of individual semi-structured interviews was carried out. Road users' perceptions were investigated before and after implementation of lane dividers (LD) and were compared with other roads in the city. Perceptions were compared using chi-square tests. In the study, 293 motorcyclists, 111 cyclists, and 115 automobile drivers were interviewed. Following the installation of the LD, the majority of motorcyclists and cyclists reported that LD made easier the driving maneuvers and decreased travel time, in contrast to perceptions of automobile drivers (p motorcycles. Further research about vulnerable road users' infrastructure is required.

  14. Simulation of three lanes one-way freeway in low visibility weather by possible traffic accidents

    Science.gov (United States)

    Pang, Ming-bao; Zheng, Sha-sha; Cai, Zhang-hui

    2015-09-01

    The aim of this work is to investigate the traffic impact of low visibility weather on a freeway including the fraction of real vehicle rear-end accidents and road traffic capacity. Based on symmetric two-lane Nagel-Schreckenberg (STNS) model, a cellular automaton model of three-lane freeway mainline with the real occurrence of rear-end accidents in low visibility weather, which considers delayed reaction time and deceleration restriction, was established with access to real-time traffic information of intelligent transportation system (ITS). The characteristics of traffic flow in different visibility weather were discussed via the simulation experiments. The results indicate that incoming flow control (decreasing upstream traffic volume) and inputting variable speed limits (VSL) signal are effective in accident reducing and road actual traffic volume's enhancing. According to different visibility and traffic demand the appropriate control strategies should be adopted in order to not only decrease the probability of vehicle accidents but also avoid congestion.

  15. Multi-lane Roundabout Capacity Evaluation

    Directory of Open Access Journals (Sweden)

    Ammar Šarić

    2017-07-01

    Full Text Available Although two-lane roundabouts theoretically exhibit excellent operating performance, in practice, safety problems arise because of inappropriate driving behavior. Turbo roundabouts, which are characterized by a much higher level of safety, are alternatives to classic two-lane roundabouts, but the capacity-related benefits derived from such roundabouts remain an open issue. Accordingly, this study uses an equilibrium traffic flow allocation approach to evaluate multi-lane roundabout capacity based on gap acceptance theory. Capacity levels are calculated and compared for different gap acceptance parameters, including local parameters, and different traffic flow scenarios. It is found that the capacity of minor approaches on turbo roundabouts is always higher than on two-lane roundabouts, but that the main approaches on two-lane roundabouts exhibit better performance in terms of fully equilibrium traffic allocation. This state, however, cannot be achieved for every demand scenario. The results depend strongly on traffic movements and gap acceptance parameters indicating the need for local calibration processes.

  16. Effects of turning and through lane sharing on traffic performance at intersections

    Science.gov (United States)

    Li, Xiang; Sun, Jian-Qiao

    2016-02-01

    Turning vehicles strongly influence traffic flows at intersections. Effective regulation of turning vehicles is important to achieve better traffic performance. This paper studies the impact of lane sharing and turning signals on traffic performance at intersections by using cellular automata. Both right-turn and left-turn lane sharing are studied. Interactions between vehicles and pedestrians are considered. The transportation efficiency, road safety and energy economy are the traffic performance metrics. Extensive simulations are carried out to study the traffic performance indices. It is observed that shared turning lanes and permissive left-turn signal improve the transportation efficiency and reduce the fuel consumption in most cases, but the safety is usually sacrificed. It is not always beneficial for the through vehicles when they are allowed to be in the turning lanes.

  17. Hydrogeomorphic connectivity on roads crossing in rural headwaters and its effect on stream dynamics.

    Science.gov (United States)

    Thomaz, Edivaldo L; Peretto, Gustavo T

    2016-04-15

    Unpaved roads are ubiquitous features that have been transforming the landscape through human history. Unpaved roads affect the water and sediment pathways through a catchment and impacts the aquatic ecosystem. In this study, we describe the effect of unpaved road on the hydrogeomorphic connectivity at the rural headwater scale. Measurement was based on the stream crossing approach, i.e., road superimposing the drainage system. We installed a Parshall flume coupled with single-stage suspended sediment sampler at each stream crossing. In addition, we displayed our monitoring scheme with an upscaling perspective from second-order to third-order stream. We concluded that the road-stream coupling dramatically changed the stream dynamic. The increase of discharge caused by roads at the headwater was 50% larger compared to unaffected streams. Additionally, suspended sediment concentration enhancement at stream crossings ranged from to 413% at second-order streams to 145% at third-order streams. The landform characteristics associated with the road network produced an important hydrogeomorphic disruption in the landscape. As a result, the sediment filter function of the riparian zone was reduced dramatically. Therefore, we recommend that projects for aquatic system restoration or conservation in rural landscape consider the role of the road network on stream dynamics. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Robust Vehicle Detection under Various Environments to Realize Road Traffic Flow Surveillance Using an Infrared Thermal Camera

    Directory of Open Access Journals (Sweden)

    Yoichiro Iwasaki

    2015-01-01

    Full Text Available To realize road traffic flow surveillance under various environments which contain poor visibility conditions, we have already proposed two vehicle detection methods using thermal images taken with an infrared thermal camera. The first method uses pattern recognition for the windshields and their surroundings to detect vehicles. However, the first method decreases the vehicle detection accuracy in winter season. To maintain high vehicle detection accuracy in all seasons, we developed the second method. The second method uses tires’ thermal energy reflection areas on a road as the detection targets. The second method did not achieve high detection accuracy for vehicles on left-hand and right-hand lanes except for two center-lanes. Therefore, we have developed a new method based on the second method to increase the vehicle detection accuracy. This paper proposes the new method and shows that the detection accuracy for vehicles on all lanes is 92.1%. Therefore, by combining the first method and the new method, high vehicle detection accuracies are maintained under various environments, and road traffic flow surveillance can be realized.

  19. Robust vehicle detection under various environments to realize road traffic flow surveillance using an infrared thermal camera.

    Science.gov (United States)

    Iwasaki, Yoichiro; Misumi, Masato; Nakamiya, Toshiyuki

    2015-01-01

    To realize road traffic flow surveillance under various environments which contain poor visibility conditions, we have already proposed two vehicle detection methods using thermal images taken with an infrared thermal camera. The first method uses pattern recognition for the windshields and their surroundings to detect vehicles. However, the first method decreases the vehicle detection accuracy in winter season. To maintain high vehicle detection accuracy in all seasons, we developed the second method. The second method uses tires' thermal energy reflection areas on a road as the detection targets. The second method did not achieve high detection accuracy for vehicles on left-hand and right-hand lanes except for two center-lanes. Therefore, we have developed a new method based on the second method to increase the vehicle detection accuracy. This paper proposes the new method and shows that the detection accuracy for vehicles on all lanes is 92.1%. Therefore, by combining the first method and the new method, high vehicle detection accuracies are maintained under various environments, and road traffic flow surveillance can be realized.

  20. Robust Vehicle Detection under Various Environments to Realize Road Traffic Flow Surveillance Using an Infrared Thermal Camera

    Science.gov (United States)

    Iwasaki, Yoichiro; Misumi, Masato; Nakamiya, Toshiyuki

    2015-01-01

    To realize road traffic flow surveillance under various environments which contain poor visibility conditions, we have already proposed two vehicle detection methods using thermal images taken with an infrared thermal camera. The first method uses pattern recognition for the windshields and their surroundings to detect vehicles. However, the first method decreases the vehicle detection accuracy in winter season. To maintain high vehicle detection accuracy in all seasons, we developed the second method. The second method uses tires' thermal energy reflection areas on a road as the detection targets. The second method did not achieve high detection accuracy for vehicles on left-hand and right-hand lanes except for two center-lanes. Therefore, we have developed a new method based on the second method to increase the vehicle detection accuracy. This paper proposes the new method and shows that the detection accuracy for vehicles on all lanes is 92.1%. Therefore, by combining the first method and the new method, high vehicle detection accuracies are maintained under various environments, and road traffic flow surveillance can be realized. PMID:25763384

  1. Properties of Phase Transition of Traffic Flow on Urban Expressway Systems with Ramps and Accessory Roads

    International Nuclear Information System (INIS)

    Mei Chaoqun; Liu Yejin

    2011-01-01

    In this paper, we develop a cellular automaton model to describe the phase transition of traffic flow on urban expressway systems with on-off-ramps and accessory roads. The lane changing rules are given in detailed, the numerical results show that the main road and the accessory road both produce phase transitions. These phase transitions will often be influenced by the number of lanes, lane changing, the ramp flow, the input flow rate, and the geometry structure. (interdisciplinary physics and related areas of science and technology)

  2. An Empirical Bayes before-after evaluation of road safety effects of a new motorway in Norway.

    Science.gov (United States)

    Elvik, Rune; Ulstein, Heidi; Wifstad, Kristina; Syrstad, Ragnhild S; Seeberg, Aase R; Gulbrandsen, Magnus U; Welde, Morten

    2017-11-01

    This paper presents an Empirical Bayes before-after evaluation of the road safety effects of a new motorway (freeway) in Østfold county, Norway. The before-period was 1996-2002. The after-period was 2009-2015. The road was rebuilt from an undivided two-lane road into a divided four-lane road. The number of killed or seriously injured road users was reduced by 75 percent, controlling for (downward) long-term trends and regression-to-the-mean (statistically significant at the 5 percent level; recorded numbers 71 before, 11 after). There were small changes in the number of injury accidents (185 before, 123 after; net effect -3%) and the number of slightly injured road users (403 before 279 after; net effect +5%). Motorways appear to mainly reduce injury severity, not the number of accidents. The paper discusses challenges in implementing the Empirical Bayes design when less than ideal data are available. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Modeling mechanical restriction differences between car and heavy truck in two-lane cellular automata traffic flow model

    Science.gov (United States)

    Li, Xin; Li, Xingang; Xiao, Yao; Jia, Bin

    2016-06-01

    Real traffic is heterogeneous with car and truck. Due to mechanical restrictions, the car and the truck have different limited deceleration capabilities, which are important factors in safety driving. This paper extends the single lane safety driving (SD) model with limited deceleration capability to two-lane SD model, in which car-truck heterogeneous traffic is considered. A car has a larger limited deceleration capability while a heavy truck has a smaller limited deceleration capability as a result of loaded goods. Then the safety driving conditions are different as the types of the following and the leading vehicles vary. In order to eliminate the well-known plug in heterogeneous two-lane traffic, it is assumed that heavy truck has active deceleration behavior when the heavy truck perceives the forming plug. The lane-changing decisions are also determined by the safety driving conditions. The fundamental diagram, spatiotemporal diagram, and lane-changing frequency were investigated to show the effect of mechanical restriction on heterogeneous traffic flow. It was shown that there would be still three traffic phases in heterogeneous traffic condition; the active deceleration of the heavy truck could well eliminate the plug; the lane-changing frequency was low in synchronized flow; the flow and velocity would decrease as the proportion of heavy truck grows or the limited deceleration capability of heavy truck drops; and the flow could be improved with lane control measures.

  4. Effects of transverse rumble strips on safety of pedestrian crosswalks on rural roads in China.

    Science.gov (United States)

    Liu, Pan; Huang, Jia; Wang, Wei; Xu, Chengcheng

    2011-11-01

    The primary objective of this study is to evaluate the impacts of transverse rumble strips in reducing crashes and vehicle speeds at pedestrian crosswalks on rural roads in China. Using crash data reported at 366 sites, the research team conducted an observational before-after study using a comparison group and the Empirical Bayesian (EB) method to evaluate the effectiveness of transverse rumble strips in reducing crashes at pedestrian crosswalks. It was found that transverse rumble strips may reduce expected crash frequency at pedestrian crosswalks by 25%. The research team collected more than 15,000 speed observations at 12 sites. The speed data analysis results show that transverse rumble strips significantly reduce vehicle speeds in vicinity of pedestrian crosswalks on rural roads with posted speed limits of 60 km/h and 80 km/h. On average, the mean speed at pedestrian crosswalks declined 9.2 km/h on roads with a speed limit of 60 km/h; and 11.9 km/h on roads with a speed limit of 80 km/h. The 85th percentile speed declined 9.1 km/h on roads with a speed limit of 60 km/h; and 12.0 km/h on roads with a speed limit of 80 km/h. However, the speed reduction impacts were not found to be statistically significant for the pedestrian crosswalk on the road with a speed limit of 40 km/h. The study also looked extensively at the influence area of transverse rumble strips on rural roads. Speed profiles developed in this study show that the influence area of transverse rumble strips is generally less than 0.3 km. Copyright © 2011 Elsevier Ltd. All rights reserved.

  5. Reducing habitat fragmentation on minor rural roads through traffic calming

    NARCIS (Netherlands)

    Jaarsma, C.F.; Willems, G.P.A.

    2002-01-01

    The rural road network suffers continually from ambiguity. On the one hand, the presence of this network and its traffic flows offer accessibility and make a contribution to economic development. While on the other, its presence and its traffic flows cause fragmentation. The actual ecological impact

  6. Lane Changing Control to Reduce Traffic Load Effect on Long-Span Bridges

    OpenAIRE

    Caprani, Colin C; Enright, Bernard; Carey, Colm

    2012-01-01

    Long span bridges are critical parts of a nation’s infrastructure network and congested traffic loading is the governing form of traffic loading. Groups of trucks travelling in conveys are created when fast-er moving vehicles, such as cars, change lane. In this research the authors investigate how the control of these lane-changing events can help reduce the traffic load effects on long span bridges. Real traffic data is used to simulate a traffic stream on a virtual road and bridge using a m...

  7. An Agent-Based Model for Optimization of Road Width and Public Transport Frequency

    Directory of Open Access Journals (Sweden)

    Mark E. Koryagin

    2015-04-01

    Full Text Available An urban passenger transportation problem is studied. Municipal authorities and passengers are regarded as participants in the passenger transportation system. The municipal authorities have to optimise road width and public transport frequency. The road consists of a dedicated bus lane and lanes for passenger cars. The car travel time depends on the number of road lanes and passengers’ choice of travel mode. The passengers’ goal is to minimize total travel costs, including time value. The passengers try to find the optimal ratio between public transport and cars. The conflict between municipal authorities and the passengers is described as a game theoretic model. The existence of Nash equilibrium in the model is proved. The numerical example shows the influence of the value of time and intensity of passenger flow on the equilibrium road width and public transport frequency.

  8. Single lane traffic in Adams road (Prévessin Site)

    CERN Multimedia

    2003-01-01

    From 20th August, ST Division will be opening trenches in order to allow a number of power, control and optical fibre cables to be laid across Adams road (see plan). For the duration of the work, the road will be barred to all heavy loads/lorries and alternative arrangements will be put in place for normal traffic. Temporary lights will be installed. We kindly ask all users to respect these temporary arrangements. The work will take two weeks given favorable conditions. Thank you for your understanding in this matter. ST-EL Group Tel. 72978 - 164082

  9. Single lane traffic in Adams road (Prévessin Site)

    CERN Document Server

    2003-01-01

    From 20th August, ST Division will be opening trenches in order to allow a number of power, control and optical fibre cables to be laid across Adams road (see plan). For the duration of the work, the road will be barred to all heavy loads/lorries and alternative arrangements will be put in place for normal traffic. Temporary lights will be installed. We kindly ask all users to respect these temporary arrangements. The work will take two weeks given favorable conditions. Thank you for your understanding in this matter. ST-EL Group Tél. 72978 - 164082

  10. An empirical Bayes safety evaluation of tram/streetcar signal and lane priority measures in Melbourne.

    Science.gov (United States)

    Naznin, Farhana; Currie, Graham; Sarvi, Majid; Logan, David

    2016-01-01

    Streetcars/tram systems are growing worldwide, and many are given priority to increase speed and reliability performance in mixed traffic conditions. Research related to the road safety impact of tram priority is limited. This study explores the road safety impacts of tram priority measures including lane and intersection/signal priority measures. A before-after crash study was conducted using the empirical Bayes (EB) method to provide more accurate crash impact estimates by accounting for wider crash trends and regression to the mean effects. Before-after crash data for 29 intersections with tram signal priority and 23 arterials with tram lane priority in Melbourne, Australia, were analyzed to evaluate the road safety impact of tram priority. The EB before-after analysis results indicated a statistically significant adjusted crash reduction rate of 16.4% after implementation of tram priority measures. Signal priority measures were found to reduce crashes by 13.9% and lane priority by 19.4%. A disaggregate level simple before-after analysis indicated reductions in total and serious crashes as well as vehicle-, pedestrian-, and motorcycle-involved crashes. In addition, reductions in on-path crashes, pedestrian-involved crashes, and collisions among vehicles moving in the same and opposite directions and all other specific crash types were found after tram priority implementation. Results suggest that streetcar/tram priority measures result in safety benefits for all road users, including vehicles, pedestrians, and cyclists. Policy implications and areas for future research are discussed.

  11. Exploring road design factors influencing tram road safety - Melbourne tram driver focus groups.

    Science.gov (United States)

    Naznin, Farhana; Currie, Graham; Logan, David

    2018-01-01

    Melbourne, Australia has the largest tram/streetcar network in the world including the largest mixed traffic tram operating environment. Therefore, Melbourne tram drivers are responsible for controlling one of the heaviest vehicles on road ranging from shared tram lanes to exclusive tram lanes. In addition to different tram lane configurations, tram drivers need to follow different traffic signal phases at intersections including tram priority signals as well as need to serve passengers at various types of closely spaced tram stops. Despite all these challenges, no research has explored tram driver perceptions of the risk factors on different tram route road design configurations. Therefore, the aim of this study is to investigate how tram drivers' safety perceptions alter along various tram route sections, signal settings and stop configurations. A tram driver focus group approach was adopted for this research involving thirty tram drivers (4 female and 26 male drivers). The tram drivers' age ranged from 29 to 63 years, with an average age of 47.6 years (standard deviation of 10.1 years), and their experience of tram driving ranged from 1.17 to 31 years, with an average experience of 12.5 years (standard deviation of 10.2 years). The participating tram drivers perceived that the raised tram tracks and tramways with raised yellow curbing beside tracks are safer lane priority features on the Melbourne tram network compared to full-time, part-time and mixed traffic tram lanes. They regarded 'hook turns' as a safe form of tram signal priority treatment at intersections and platform tram stops as the safest tram stop design for all passengers among all other tram stop designs in Melbourne. Findings of this research could enhance the understanding of crash risk factors for different tram route features and thus can offer effective planning strategies for transit agencies to improve tram road safety. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Modeling Lane-Changing Behavior in Freeway Off-Ramp Areas from the Shanghai Naturalistic Driving Study

    Directory of Open Access Journals (Sweden)

    Lanfang Zhang

    2018-01-01

    Full Text Available The objective of this study is to investigate lane-changing characteristics in freeway off-ramp areas using Shanghai Naturalistic Driving Study (SH-NDS data, considering a four-lane freeway stretch in various traffic conditions. In SH-NDS, the behavior of drivers is observed unobtrusively in a natural setting for a long period of time. We identified 433 lane-changing events with valid time series data from the whole dataset. Based on the logit model developed to analyze the choice of target lanes, a likelihood analysis of lane-changing behavior was graphed with respect to three traffic conditions: free flow, medium flow, and heavy flow. The results suggested that lane-changing behavior of exiting vehicles is the consequence of the balance between route plan (mandatory incentive and expectation to improve driving condition (discretionary incentive. In higher traffic density, the latter seems to play a significant role. Furthermore, we found that lane-change from the slow lane to the fast lane would lead to higher speed variance value, which indicates a higher crash risk. The findings contribute to a better understanding on drivers’ natural driving behavior in freeway off-ramp areas and can provide important insight into road network design and safety management strategies.

  13. Lane Level Localization; Using Images and HD Maps to Mitigate the Lateral Error

    Science.gov (United States)

    Hosseinyalamdary, S.; Peter, M.

    2017-05-01

    In urban canyon where the GNSS signals are blocked by buildings, the accuracy of measured position significantly deteriorates. GIS databases have been frequently utilized to improve the accuracy of measured position using map matching approaches. In map matching, the measured position is projected to the road links (centerlines) in this approach and the lateral error of measured position is reduced. By the advancement in data acquision approaches, high definition maps which contain extra information, such as road lanes are generated. These road lanes can be utilized to mitigate the positional error and improve the accuracy in position. In this paper, the image content of a camera mounted on the platform is utilized to detect the road boundaries in the image. We apply color masks to detect the road marks, apply the Hough transform to fit lines to the left and right road boundaries, find the corresponding road segment in GIS database, estimate the homography transformation between the global and image coordinates of the road boundaries, and estimate the camera pose with respect to the global coordinate system. The proposed approach is evaluated on a benchmark. The position is measured by a smartphone's GPS receiver, images are taken from smartphone's camera and the ground truth is provided by using Real-Time Kinematic (RTK) technique. Results show the proposed approach significantly improves the accuracy of measured GPS position. The error in measured GPS position with average and standard deviation of 11.323 and 11.418 meters is reduced to the error in estimated postion with average and standard deviation of 6.725 and 5.899 meters.

  14. LANE LEVEL LOCALIZATION; USING IMAGES AND HD MAPS TO MITIGATE THE LATERAL ERROR

    Directory of Open Access Journals (Sweden)

    S. Hosseinyalamdary

    2017-05-01

    Full Text Available In urban canyon where the GNSS signals are blocked by buildings, the accuracy of measured position significantly deteriorates. GIS databases have been frequently utilized to improve the accuracy of measured position using map matching approaches. In map matching, the measured position is projected to the road links (centerlines in this approach and the lateral error of measured position is reduced. By the advancement in data acquision approaches, high definition maps which contain extra information, such as road lanes are generated. These road lanes can be utilized to mitigate the positional error and improve the accuracy in position. In this paper, the image content of a camera mounted on the platform is utilized to detect the road boundaries in the image. We apply color masks to detect the road marks, apply the Hough transform to fit lines to the left and right road boundaries, find the corresponding road segment in GIS database, estimate the homography transformation between the global and image coordinates of the road boundaries, and estimate the camera pose with respect to the global coordinate system. The proposed approach is evaluated on a benchmark. The position is measured by a smartphone’s GPS receiver, images are taken from smartphone’s camera and the ground truth is provided by using Real-Time Kinematic (RTK technique. Results show the proposed approach significantly improves the accuracy of measured GPS position. The error in measured GPS position with average and standard deviation of 11.323 and 11.418 meters is reduced to the error in estimated postion with average and standard deviation of 6.725 and 5.899 meters.

  15. Traffic conflict assessment for non-lane-based movements of motorcycles under congested conditions

    Directory of Open Access Journals (Sweden)

    Long Xuan Nguyen

    2014-03-01

    Full Text Available Traffic conflict under congested conditions is one of the main safety issues of motorcycle traffic in developing countries. Unlike cars, motorcycles often display non-lane-based movements such as swerving or oblique following of a lead vehicle when traffic becomes congested. Very few studies have quantitatively evaluated the effects of such non-lane-based movements on traffic conflict. Therefore, in this study we aim to develop an integrated model to assess the traffic conflict of motorcycles under congested conditions. The proposed model includes a concept of safety space to describe the non-lane-based movements unique to motorcycles, new features developed for traffic conflict assessment such as parameters of acceleration and deceleration, and the conditions for choosing a lead vehicle. Calibration data were extracted from video clips taken at two road segments in Ho Chi Minh City. A simulation based on the model was developed to verify the dynamic non-lane-based movements of motorcycles. Subsequently, the assessment of traffic conflict was validated by calculating the probability of sudden braking at each time interval according to the change in the density of motorcycle flow. Our findings underscore the fact that higher flow density may lead to conflicts associated with a greater probability of sudden breaking. Three types of motorcycle traffic conflicts were confirmed, and the proportions of each type were calculated and discussed.

  16. Brick Lane Patchwork

    Directory of Open Access Journals (Sweden)

    Emanuele Monegato

    2009-12-01

    Full Text Available The essay Brick Lane Patchwork takes its roots in the consideration that the most effective cultural representations of London Brick Lane are explicitly or implicitly linked to the nature of a patchwork. Many contemporary cultural representations made a vain and ambitious effort to portray the real soul(s of Brick Lane, without taking into consideration its complexity and, therefore, delivering a distinctive image of the area as if it was a single piece of cloth, not a whole quilt. Starting from already existing cultural representations of Brick Lane (Monica Ali's first novel Brick Lane and its filmic adaptation directed by Sarah Gavron, the poetic memoir Salaam Brick Lane - a Year in the New East End and the short film Brick Lane by Paul Makkar, which are going to be privileged squared cloths to be sewn in the above mentioned patchwork, the aim of this essay is both to detect its proper cultural representations and to sew an imaginative patchwork quilt, a new and multiple image of this London area enhancing its hybrid soul(s, its blending procedure and contemporary facets. Ali M., 2004, Brick Lane, Doubleday Black Swan, London.Gavron S., 2007, Brick Lane, Sony Pictures Classics.Hall T., 2005, Salaam Brick Lane - A Year in the New East End, John Murray Publishers, London. Makkar P., 2002, Brick Lane, Anapurna Films.

  17. Road Interpretation for Driver Assistance Based on an Early Cognitive Vision System

    DEFF Research Database (Denmark)

    Baseski, Emre; Jensen, Lars Baunegaard With; Pugeault, Nicolas

    2009-01-01

    In this work, we address the problem of road interpretation for driver assistance based on an early cognitive vision system. The structure of a road and the relevant traffic are interpreted in terms of ego-motion estimation of the car, independently moving objects on the road, lane markers and large...... scale maps of the road. We make use of temporal and spatial disambiguation mechanisms to increase the reliability of visually extracted 2D and 3D information. This information is then used to interpret the layout of the road by using lane markers that are detected via Bayesian reasoning. We also...... estimate the ego-motion of the car which is used to create large scale maps of the road and also to detect independently moving objects. Sample results for the presented algorithms are shown on a stereo image sequence, that has been collected from a structured road....

  18. Microscopic Model of Automobile Lane-changing Virtual Desire Trajectory by Spline Curves

    Directory of Open Access Journals (Sweden)

    Yulong Pei

    2010-05-01

    Full Text Available With the development of microscopic traffic simulation models, they have increasingly become an important tool for transport system analysis and management, which assist the traffic engineer to investigate and evaluate the performance of transport network systems. Lane-changing model is a vital component in any traffic simulation model, which could improve road capacity and reduce vehicles delay so as to reduce the likelihood of congestion occurrence. Therefore, this paper addresses the virtual desire trajectory, a vital part to investigate the behaviour divided into four phases. Based on the boundary conditions, β-spline curves and the corresponding reverse algorithm are introduced firstly. Thus, the relation between the velocity and length of lane-changing is constructed, restricted by the curvature, steering velocity and driving behaviour. Then the virtual desire trajectory curves are presented by Matlab and the error analysis results prove that this proposed description model has higher precision in automobile lane-changing process reconstruction, compared with the surveyed result. KEY WORDS: traffic simulation, lane-changing model, virtual desire trajectory, β-spline curves, driving behaviour

  19. Lane Changing and Lane Utilization Behavior for Three Lane Normal Section in Iraq Traffic Sites

    Directory of Open Access Journals (Sweden)

    Hamid Athab Eedan Al-Jameel

    2017-05-01

    Full Text Available Recently, different programs or methods have been produced to solve the traffic problem everywhere in the world. Iraq is one of the countries which suffer from high problems in traffic operation, design and planning. Therefore, to use the sophisticated traffic programs or models such as simulation models there is an urgent need to investigate specified field parameters which correspond to calibrated parameters used in the model under study. This study has focused on studying driver behavior which represents the core stone in a traffic simulation. This behavior represents lane changing (LC and lane utilization (LU in normal sections. Three normal sections with three lanes have been selected in different sites in Iraq: two sites in Al-Najaf city and one site in Al-Muthna city. The results of data analysis show that the driver behavior in both LC and LU is similar to the behavior in the UK. The current observed data could be used for the calibration process for any traffic simulation model in order to mimic the reality of Iraqi drivers.

  20. Risk and safety perception on urban and rural roads: Effects of environmental features, driver age and risk sensitivity.

    Science.gov (United States)

    Cox, Jolene A; Beanland, Vanessa; Filtness, Ashleigh J

    2017-10-03

    The ability to detect changing visual information is a vital component of safe driving. In addition to detecting changing visual information, drivers must also interpret its relevance to safety. Environmental changes considered to have high safety relevance will likely demand greater attention and more timely responses than those considered to have lower safety relevance. The aim of this study was to explore factors that are likely to influence perceptions of risk and safety regarding changing visual information in the driving environment. Factors explored were the environment in which the change occurs (i.e., urban vs. rural), the type of object that changes, and the driver's age, experience, and risk sensitivity. Sixty-three licensed drivers aged 18-70 years completed a hazard rating task, which required them to rate the perceived hazardousness of changing specific elements within urban and rural driving environments. Three attributes of potential hazards were systematically manipulated: the environment (urban, rural); the type of object changed (road sign, car, motorcycle, pedestrian, traffic light, animal, tree); and its inherent safety risk (low risk, high risk). Inherent safety risk was manipulated by either varying the object's placement, on/near or away from the road, or altering an infrastructure element that would require a change to driver behavior. Participants also completed two driving-related risk perception tasks, rating their relative crash risk and perceived risk of aberrant driving behaviors. Driver age was not significantly associated with hazard ratings, but individual differences in perceived risk of aberrant driving behaviors predicted hazard ratings, suggesting that general driving-related risk sensitivity plays a strong role in safety perception. In both urban and rural scenes, there were significant associations between hazard ratings and inherent safety risk, with low-risk changes perceived as consistently less hazardous than high

  1. Pedestrian Safety in Road Traffic in Poland

    Science.gov (United States)

    Budzynski, Marcin; Jamroz, Kazimierz; Mackun, Tomasz

    2017-10-01

    Every third road accident in Poland involves a pedestrian as a participant or, most of the time, a casualty. Pedestrian accidents are usually the result of complex situations and the outcome of a number of factors related to driver and pedestrian behaviour and road infrastructure. Safety depends largely on how well the traffic condition is perceived and on visibility in traffic. The paper presents the results of analyses of methodologies for systematic studies of pedestrian behaviour and pedestrian-driver relations. The effects of the location of the site, type of cross-section and other selected parameters on pedestrian and driver behaviour are demonstrated. The analyses showed that pedestrians are most often put at risk by too long pedestrian crossings, vehicles going too fast around pedestrian crossings, lack of proper sight distance and poorly lit or unlit pedestrian crossings. The reason for such defective infrastructure is that planners, designers, contractors and maintenance services are not receiving any support from design, marking and maintenance regulations for pedestrian traffic. In addition, the Road Traffic Law is not restrictive enough when it comes to drivers’ obligations towards pedestrian safety. Polish design regulations allow long pedestrian crossings up to four lanes in one direction or three lanes in two directions irrespective of traffic control and speed limits. Pedestrian crossings should be kept at a maximum of three lanes. There is nothing in the design regulations about the required driver-pedestrian sight distance. Neither does the Road Traffic Law help engineers with that. It is legal to park vehicles within 10 m of a pedestrian crossing which does not guarantee the necessary sight distance. Drivers must be able to see a pedestrian waiting or stepping onto the crossing from a distance that will help them come to a stop safely. It is safer to follow the principle of providing adequate pedestrian sight distance. Recommendations for

  2. Armenia - Rural Road Rehabilitation

    Data.gov (United States)

    Millennium Challenge Corporation — The key research questions guiding our design of the RRRP evaluation are: • Did rehabilitating roads affect the quality of roads? • Did rehabilitating roads improve...

  3. Environmental implications of Universal Rural Road Access Program (URRAP roads in Southwestern Ethiopia: The case of Jimma and Buno Bedelle zones

    Directory of Open Access Journals (Sweden)

    Hassen Negesso

    2018-03-01

    Full Text Available Ethiopia has been undertaking numerous development programs and projects with the objective of taking a country to the middle-income countries in the near future. Universal Rural Road Access Program (URRAP roads being constructed in Jimma and Bunno Bedele zones are among the projects in Ethiopia. Although these projects are assumed to bring desirable positive change, there are sometimes negative consequences on environmental issues. Accordingly, the objective of this study was to investigate the negative sides of these projects on environmental elements. Household survey with randomly selected household heads and in-depth interview, focus group discussion (FGD and observation for purposively selected samples were used to collect relevant and required data. Thereby, data were analyzed quantitatively by using Statistical Package for Social Sciences (SPSS and qualitatively through thematic method. The findings from the analyzed data show that rural roads being constructed by URRAP have both positive and negative impacts on plant species, bird species, reptile species, mammal’s species, amphibians’ species, soil, and climate. Finally, URRAP is in dilemma and needs an extensive and frequent supervision, monitoring, inclusive, interdisciplinary and sound strategies and policies by responsible bodies at all expected levels and contexts.

  4. Testing bird response to roads on a rural environment: A case study from Central Italy

    Science.gov (United States)

    Morelli, Federico; Jerzak, Leszek; Pruscini, Fabio; Santolini, Riccardo; Benedetti, Yanina; Tryjanowski, Piotr

    2015-11-01

    The construction of roads is currently well spread in many parts of our world and impacts strongly on wildlife distribution. Some bird species avoid, while other prefer to be in the vicinity of these human structures. However, studies on roads effects on birds, in terms of strength or direction of these effects, are scarce. Therefore, in a study carried out in Central Italy we tested the responses of different bird species to roads at a local spatial scale, using generalized linear models (GLM). Analysis were conducted on a large dataset (more than 1400 sampled sites, mainly on rural environments). Both positive and negative effects of roads on birds were found for bird species of close or semi-close environments, while the negative effects of roads were negligible for bird species of open and semi-open environments. This fact suggest that roads can be a source of "functional heterogeneity" on semi-open environments, providing marginal habitats, hedgerows and residual vegetation typical of roadsides, offering breeding and feeding habitat for some bird species. The proposed methodology provide a useful explorative tool, in order to develop conservation policies to preserve the biodiversity, mainly in rural landscapes. The outputs of GLM can be used as inputs in ecological planning: direction and strength of the effects of roads on bird species are adequate to estimate the response of bird community, up front to the presence of new structures, or identifying which of them should be mitigated to reduce negative effects on the biodiversity.

  5. Source diagnostics of polycyclic aromatic hydrocarbons in urban road runoff, dust, rain and canopy throughfall.

    Science.gov (United States)

    Zhang, Wei; Zhang, Shucai; Wan, Chao; Yue, Dapan; Ye, Youbin; Wang, Xuejun

    2008-06-01

    Diagnostic ratios and multivariate analysis were utilized to apportion polycyclic aromatic hydrocarbon (PAH) sources for road runoff, road dust, rain and canopy throughfall based on samples collected in an urban area of Beijing, China. Three sampling sites representing vehicle lane, bicycle lane and branch road were selected. For road runoff and road dust, vehicular emission and coal combustion were identified as major sources, and the source contributions varied among the sampling sites. For rain, three principal components were apportioned representing coal/oil combustion (54%), vehicular emission (34%) and coking (12%). For canopy throughfall, vehicular emission (56%), coal combustion (30%) and oil combustion (14%) were identified as major sources. Overall, the PAH's source for road runoff mainly reflected that for road dust. Despite site-specific sources, the findings at the study area provided a general picture of PAHs sources for the road runoff system in urban area of Beijing.

  6. A two-Lane model with anomalous slow dynamics

    Science.gov (United States)

    Linford, Dan; Richards, Trevor; Pleimling, Michel

    2011-10-01

    It is known that in one-dimensional equilibrium systems with short range interactions a phase transition cannot exist at finite, non-zero temperatures. However, far from equilibrium, one-dimensional systems with local interactions can exhibit a phase transition. The ABC model, a three species model defined on a chain characterized by non-symmetric exchanges between particles, is known to possess a non-equilibrium phase transition. This model exhibits anomalous slow dynamics that we investigate in some detail using two-time quantities. In addition we discuss an extension of this model to a case where this single lane is coupled to a one-dimensional particle bath. This coupling yields an additional phase transition that we discuss in some detail.

  7. Circulatory Markings at Double-Lane Traffic Roundabout.

    NARCIS (Netherlands)

    Bie, Jing; Lo, Hong K.; Wong, S.C.

    2008-01-01

    This paper compares two types of circulatory markings at a double-lane traffic roundabout: the concentric marking scheme and the Alberta marking scheme. The effects of these two marking schemes on drivers' lane choice behavior, delay, and safety, are compared based on data collected from before and

  8. Computer Vision Based Smart Lane Departure Warning System for Vehicle Dynamics Control

    Directory of Open Access Journals (Sweden)

    Ambarish G. Mohapatra

    2011-09-01

    Full Text Available Collision Avoidance System solves many problems caused by traffic congestion worldwide and a synergy of new information technologies for simulation, real-time control and communications networks. The above system is characterized as an intelligent vehicle system. Traffic congestion has been increasing world-wide as a result of increased motorization, urbanization, population growth and changes in population density. Congestion reduces utilization of the transportation infrastructure and increases travel time, air pollution, fuel consumption and most importantly traffic accidents. The main objective of this work is to develop a machine vision system for lane departure detection and warning to measure the lane related parameters such as heading angle, lateral deviation, yaw rate and sideslip angle from the road scene image using standard image processing technique that can be used for automation of steering a motor vehicle. The exact position of the steering wheel can be monitored using a steering wheel sensor. This core part of this work is based on Hough transformation based edge detection technique for the detection of lane departure parameters. The prototype designed for this work has been tested in a running vehicle for the monitoring of real-time lane related parameters.

  9. Correspondence between Simulator and On-Road Drive Performance: Implications for Assessment of Driving Safety.

    Science.gov (United States)

    Aksan, Nazan; Hacker, Sarah D; Sager, Lauren; Dawson, Jeffrey; Anderson, Steven; Rizzo, Matthew

    2016-03-01

    Forty-two younger (Mean age = 35) and 37 older drivers (Mean age = 77) completed four similar simulated drives. In addition, 32 younger and 30 older drivers completed a standard on-road drive in an instrumented vehicle. Performance in the simulated drives was evaluated using both electronic drive data and video-review of errors. Safety errors during the on-road drive were evaluated by a certified driving instructor blind to simulator performance, using state Department of Transportation criteria. We examined the degree of convergence in performance across the two platforms on various driving tasks including lane change, lane keeping, speed control, stopping, turns, and overall performance. Differences based on age group indicated a pattern of strong relative validity for simulator measures. However, relative rank-order in specific metrics of performance suggested a pattern of moderate relative validity. The findings have implications for the use of simulators in assessments of driving safety as well as its use in training and/or rehabilitation settings.

  10. Understanding the emission impacts of high-occupancy vehicle (HOV) to high-occupancy toll (HOT) lane conversions: Experience from Atlanta, Georgia.

    Science.gov (United States)

    Xu, Yanzhi Ann; Liu, Haobing; Rodgers, Michael O; Guin, Angshuman; Hunter, Michael; Sheikh, Adnan; Guensler, Randall

    2017-08-01

    Converting a congested high-occupancy vehicle (HOV) lane into a high-occupancy toll (HOT) lane is a viable option for improving travel time reliability for carpools and buses that use the managed lane. However, the emission impacts of HOV-to-HOT conversions are not well understood. The lack of emission impact quantification for HOT conversions creates a policy challenge for agencies making transportation funding choices. The goal of this paper is to evaluate the case study of before-and-after changes in vehicle emissions for the Atlanta, Georgia, I-85 HOV/HOT lane conversion project, implemented in October 2011. The analyses employed the Motor Vehicle Emission Simulator (MOVES) for project-level analysis with monitored changes in vehicle activity data collected by Georgia Tech researchers for the Georgia Department of Transportation (GDOT). During the quarterly field data collection from 2010 to 2012, more than 1.5 million license plates were observed and matched to vehicle class and age information using the vehicle registration database. The study also utilized the 20-sec, lane-specific traffic operations data from the Georgia NaviGAtor intelligent transportation system, as well as a direct feed of HOT lane usage data from the State Road and Tollway Authority (SRTA) managed lane system. As such, the analyses in this paper simultaneously assessed the impacts associated with changes in traffic volumes, on-road operating conditions, and fleet composition before and after the conversion. Both greenhouse gases and criteria pollutants were examined. A straight before-after analysis showed about 5% decrease in air pollutants and carbon dioxide (CO 2 ). However, when the before-after calendar year of analysis was held constant (to account for the effect of 1 yr of fleet turnover), mass emissions at the analysis site during peak hours increased by as much as 17%, with little change in CO 2 . Further investigation revealed that a large percentage decrease in criteria

  11. Design and development of multi-lane smart electromechanical actuators

    CERN Document Server

    Annaz, Fawaz Yahya

    2014-01-01

    Design and Development of Multi-Lane Smart Electromechanical Actuators presents the design of electromechanical actuators in two types of architectures, namely, Torque Summed Architecture (TSA) and Velocity Summed Architecture, (VSA). It examines them in: * Hardware redundancy, where the architecture is made up of 3 or 4 lanes. * Digital Math Model redundancy, where a more compact two lanes architectures will be presented. The book starts with the very basic concepts and introduces the design process logically so that an understanding of the smart multi-lane systems that drive an aileron

  12. Source diagnostics of polycyclic aromatic hydrocarbons in urban road runoff, dust, rain and canopy throughfall

    International Nuclear Information System (INIS)

    Zhang Wei; Zhang Shucai; Wan Chao; Yue Dapan; Ye Youbin; Wang Xuejun

    2008-01-01

    Diagnostic ratios and multivariate analysis were utilized to apportion polycyclic aromatic hydrocarbon (PAH) sources for road runoff, road dust, rain and canopy throughfall based on samples collected in an urban area of Beijing, China. Three sampling sites representing vehicle lane, bicycle lane and branch road were selected. For road runoff and road dust, vehicular emission and coal combustion were identified as major sources, and the source contributions varied among the sampling sites. For rain, three principal components were apportioned representing coal/oil combustion (54%), vehicular emission (34%) and coking (12%). For canopy throughfall, vehicular emission (56%), coal combustion (30%) and oil combustion (14%) were identified as major sources. Overall, the PAH's source for road runoff mainly reflected that for road dust. Despite site-specific sources, the findings at the study area provided a general picture of PAHs sources for the road runoff system in urban area of Beijing. - Urban road runoff and road dust, canopy throughfall and rain were considered as a system for diagnostics of PAH sources

  13. Comparisons of mandatory and discretionary lane changing behavior on freeways

    Directory of Open Access Journals (Sweden)

    Matthew Vechione

    2018-06-01

    Full Text Available This research performs comparative analyses on drivers’ behavior during mandatory and discretionary lane changes. We do this by examining the statistical properties of four lane changing decision variables that describe the gaps between the subject vehicle and the surrounding vehicles. Mandatory and discretionary lane changes in NGSIM’s I-80 Freeway and U.S. Highway 101 data collection sites were identified. First, for each variable at the same site, descriptive statistics for the two types of lane changes were compared, and hypothesis tests on the difference between two means were conducted. Then, for each decision variable at the same site, the observed cumulative distributions between the mandatory and discretionary lane changes were compared by means of the Kolmogorov–Smirnov test. This test was repeated for the fitted distributions of the same decision variable at the same site. The results show that, for the three decision variables associated with gaps in the target lane, the means and distributions between the two types of lane changes are not significantly different. The only variable found to have significant differences in means and distributions is the gap between the subject vehicle and the preceding vehicle in the original lane. This may be because this variable is not an important input in mandatory lane change decisions. This finding provides statistical justification for researchers to develop models with different inputs for mandatory and discretionary lane changes in driver assist systems, in autonomous vehicles, and in microscopic traffic simulation tools.

  14. Extraction of basic roadway information for non-state roads in Florida : [summary].

    Science.gov (United States)

    2015-07-01

    The Florida Department of Transportation (FDOT) maintains a map of all the roads in Florida, : containing over one and a half million road links. For planning purposes, a wide variety : of information, such as stop lights, signage, lane number, and s...

  15. Lane detection algorithm for an onboard camera

    Science.gov (United States)

    Bellino, Mario; Lopez de Meneses, Yuri; Ryser, Peter; Jacot, Jacques

    2005-02-01

    After analysing the major causes of injuries and death on roads, it is understandable that one of the main goals in the automotive industry is to increase vehicle safety. The European project SPARC (Secure Propulsion using Advanced Redundant Control) is developing the next generation of trucks that will fulfil these aims. The main technologies that will be used in the SPARC project to achieve the desiderated level of safety will be presented. In order to avoid accidents in critical situations, it is necessary to have a representation of the environment of the vehicle. Thus, several solutions using different sensors will be described and analysed. Particularly, a division of this project aims to integrate cameras in automotive vehicles to increase security and prevent driver's mistakes. Indeed, with this vision platform it would be possible to extract the position of the lane with respect to the vehicle, and thus, help the driver to follow the optimal trajectory. A definition of lane is proposed, and a lane detection algorithm is presented. In order to improve the detection, several criteria are explained and detailed. Regrettably, such an embedded camera is subject to the vibration of the truck, and the resulting sequence of images is difficult to analyse. Thus, we present different solutions to stabilize the images and particularly a new approach developed by the "Laboratoire de Production Microtechnique". Indeed, it was demonstrated in previous works that the presence of noise can be used, through a phenomenon called Stochastic Resonance. Thus, instead of decreasing the influence of noise in industrial applications, which has non negligible costs, it is perhaps interesting to use this phenomenon to reveal some useful information, such as for example the contour of the objects and lanes.

  16. Evaluación de los caminos rurales: hacia un enfoque orientado al usuario. / Assessment of rural roads. Towards a user-oriented approach.

    Directory of Open Access Journals (Sweden)

    González, Sergio

    2000-03-01

    Full Text Available Este trabajo presente algunos resultados de un estudio piloto realizado para el IFRTD (Foro Internacional para el Transporte Rural y el Desarrollo, Londres sobre los temas de movilización y vialidad en la comuna de Canela, IV Región de Chile. El planteamiento es que una política coherente de vialidad rural debe tener como fundamento un entendimiento de las necesidades percibidas por las comunidades rurales y de las prioridades que expresan. Este tema se explora en el proyecto en forma preliminar utilizando metodologías cualitativas y cuantitativas para investigar las necesidades de movilización en diversas comunidades de Canela desde el punto de vista de los usuarios, operadores de transporte y autoridades locales. Se presentará un análisis de los resultados pertinentes al asunto de la vialidad, que pretende establecer de manera tentativa un perfil del usuario de los caminos rurales de la zona y las características de sus traslados más difíciles. Entre los resultados más significativos se destacan:Una percepción de los amplios efectos modernizadores que introduce la pavimentación de un camino de acceso al sector.La existencia de una correlación baja pero positiva entre la dificultad percibida por el usuario de su traslado y su evaluación del camino, que se ve relacionado con el modo de transporte que se ocupa.La conclusión principal del trabajo es que un conocimiento de los criterios propios con los cuales el usuario rural evalúa su traslado es necesario para una gestión exitosa de la vialidad rural./The author argues that a coherent policy for rural roads should be founded on the understanding of the perceived needs of rural communities and the priorities expressed. It describes the Methodological approaches to assess, in this way, rural roads.

  17. Characteristics of on-road driving performance of persons with central vision loss who use bioptic telescopes.

    Science.gov (United States)

    Wood, Joanne M; McGwin, Gerald; Elgin, Jennifer; Searcey, Karen; Owsley, Cynthia

    2013-05-01

    To compare the on-road driving performance of visually impaired drivers using bioptic telescopes with age-matched controls. Participants included 23 persons (mean age = 33 ± 12 years) with visual acuity of 20/63 to 20/200 who were legally licensed to drive through a state bioptic driving program, and 23 visually normal age-matched controls (mean age = 33 ± 12 years). On-road driving was assessed in an instrumented dual-brake vehicle along 14.6 miles of city, suburban, and controlled-access highways. Two backseat evaluators independently rated driving performance using a standardized scoring system. Vehicle control was assessed through vehicle instrumentation and video recordings used to evaluate head movements, lane-keeping, pedestrian detection, and frequency of bioptic telescope use. Ninety-six percent (22/23) of bioptic drivers and 100% (23/23) of controls were rated as safe to drive by the evaluators. There were no group differences for pedestrian detection, or ratings for scanning, speed, gap judgments, braking, indicator use, or obeying signs/signals. Bioptic drivers received worse ratings than controls for lane position and steering steadiness and had lower rates of correct sign and traffic signal recognition. Bioptic drivers made significantly more right head movements, drove more often over the right-hand lane marking, and exhibited more sudden braking than controls. Drivers with central vision loss who are licensed to drive through a bioptic driving program can display proficient on-road driving skills. This raises questions regarding the validity of denying such drivers a license without the opportunity to train with a bioptic telescope and undergo on-road evaluation.

  18. Satellite Remote Sensing and Transportation Lifelines: Safety and Risk Analysis Along Rural Roads

    Science.gov (United States)

    Williamson, R.

    the application of satellite Earth Observation (EO) methods to the analysis of transportation networks. Other geospatial technologies, including geographic information systems (GIS) and the Global Positioning System (GPS), sharply enhance the utility of EO data in identifying potential road hazards and providing an objective basis for allocating resources to reduce their risks. In combination, these powerful information technologies provide substantial public benefits and increased business opportunities to remote sensing value-added firms. departments in rural jurisdictions improve the trafficability of the roads under their management during severe weather. We are developing and testing these methods in the U.S. Southwest, where thousands of kilometers of unimproved and graded dirt roads cross Native American reservations. This generally arid region is nevertheless subject to periodic summer rainstorms and winter snow and ice, creating hazardous conditions for the region's transportation lifelines. Arizona and Southeast Utah, as well as digital terrain models from the U.S. Geological Survey. We have analyzed several risk factors, such as slope, road curvature, and intersections, by means of multi-criteria evaluation (MCE) on both unimproved and improved roads. In partnership with the Hopi Indian Nation in Arizona, we have acquired and analyzed GPS road centerline data and accident data that validate our methodology. hazards along paved and unpaved roads of the American Southwest. They are also transferable to the international settings, particularly in similarly arid climates.

  19. Effects of new roads on environmental resource use in the Central Himalaya

    DEFF Research Database (Denmark)

    Charlery, Lindy Callen; Nielsen, Martin Reinhardt; Meilby, Henrik

    2016-01-01

    Construction of roads into remote rural areas can improve livelihoods by reducing transportation costs, but may also have negative environmental impacts, such as increased deforestation. However, evidence of the effect of rural roads on household environmental income and reliance, as well as local...... income and reliance, and how are they affected by road establishment; and (iii) what are the short-term impacts of the construction of a rural road on local forest conservation? Following the Poverty Environment Network (PEN) methodology, income data from 176 randomly-sampled households were collected...... in 2006 from two similar Himalayan villages, Lete and Lulang, and again in 2012 after a new road was constructed in 2008 in Lete. Forest strata data were collected in Lete through permanent sample plots (n = 59) measured in 2005 and 2010 and used to estimate stock change (before and after road...

  20. Motion Planning of Autonomous Vehicles on a Dual Carriageway without Speed Lanes

    Directory of Open Access Journals (Sweden)

    Rahul Kala

    2015-01-01

    Full Text Available The problem of motion planning of an autonomous vehicle amidst other vehicles on a straight road is considered. Traffic in a number of countries is unorganized, where the vehicles do not move within predefined speed lanes. In this paper, we formulate a mechanism wherein an autonomous vehicle may travel on the “wrong” side in order to overtake a vehicle. Challenges include assessing a possible overtaking opportunity, cooperating with other vehicles, partial driving on the “wrong” side of the road and safely going to and returning from the “wrong” side. The experimental results presented show vehicles cooperating to accomplish overtaking manoeuvres.

  1. Robust lane detection and tracking using multiple visual cues under stochastic lane shape conditions

    Science.gov (United States)

    Huang, Zhi; Fan, Baozheng; Song, Xiaolin

    2018-03-01

    As one of the essential components of environment perception techniques for an intelligent vehicle, lane detection is confronted with challenges including robustness against the complicated disturbance and illumination, also adaptability to stochastic lane shapes. To overcome these issues, we proposed a robust lane detection method named classification-generation-growth-based (CGG) operator to the detected lines, whereby the linear lane markings are identified by synergizing multiple visual cues with the a priori knowledge and spatial-temporal information. According to the quality of linear lane fitting, the linear and linear-parabolic models are dynamically switched to describe the actual lane. The Kalman filter with adaptive noise covariance and the region of interests (ROI) tracking are applied to improve the robustness and efficiency. Experiments were conducted with images covering various challenging scenarios. The experimental results evaluate the effectiveness of the presented method for complicated disturbances, illumination, and stochastic lane shapes.

  2. Pattern of Injuries from Road Traffic Accidents Presented at a Rural Teaching Institution of Karachi.

    Science.gov (United States)

    Shamim, Muhammad

    2017-08-01

    The aim of the study is to study the pattern of injuries from road traffic accidents presented at the emergency department of a rural teaching institution in Karachi. This descriptive case series was conducted prospectively in the Emergency Department of Fatima Hospital and Baqai Medical University from 1 January 2012 to 21 March 2013. There were 385 patients in the series. All of the patients with recent injuries from road traffic accidents were included. Cases with injuries more than 72 h old were excluded. The majority of patients had lower limb injuries 172 (44.7%), followed by head and neck injuries 107 (27.8%), multiple injuries 62 (16.1%), upper limb injuries 22 (5.7%), abdominoperineal injuries 19 (5%), and chest injuries 3 (0.8%). Majority (229, 59.5%) of patients were given first aid treatment and discharged, while 151 (39.3%) patients were either admitted or referred to better equipped hospitals. Three patients were brought dead, and two patients left against medical advice. The lower limb injuries were the commonest road traffic accidental injuries, followed by head and neck injuries, multiple injuries, upper limb injuries, abdominoperineal injuries, and chest injuries.

  3. Modelling Free Flow Speed on Two-Lane Rural Highways in Bosnia and Herzegovina

    Directory of Open Access Journals (Sweden)

    Ivan Lovrić

    2014-04-01

    Full Text Available Free flow speed is used as a parameter in transportation planning and capacity analysis models, as well as speed-flow diagrams. Many of these models suggest estimating free flow speed according to measurements from similar highways, which is not a practical method for use in B&H. This paper first discusses problems with using these methodologies in conditions prevailing in B&H and then presents a free flow speed evaluation model developed from a comprehensive field survey conducted on nine homogeneous sections of state and regional roads.

  4. Assessing and Mapping of Road Surface Roughness based on GPS and Accelerometer Sensors on Bicycle-Mounted Smartphones

    Science.gov (United States)

    Shen, Jie; Wan, Mi; Shi, Jiafeng

    2018-01-01

    The surface roughness of roads is an essential road characteristic. Due to the employed carrying platforms (which are often cars), existing measuring methods can only be used for motorable roads. Until now, there has been no effective method for measuring the surface roughness of un-motorable roads, such as pedestrian and bicycle lanes. This hinders many applications related to pedestrians, cyclists and wheelchair users. In recognizing these research gaps, this paper proposes a method for measuring the surface roughness of pedestrian and bicycle lanes based on Global Positioning System (GPS) and accelerometer sensors on bicycle-mounted smartphones. We focus on the International Roughness Index (IRI), as it is the most widely used index for measuring road surface roughness. Specifically, we analyzed a computing model of road surface roughness, derived its parameters with GPS and accelerometers on bicycle-mounted smartphones, and proposed an algorithm to recognize potholes/humps on roads. As a proof of concept, we implemented the proposed method in a mobile application. Three experiments were designed to evaluate the proposed method. The results of the experiments show that the IRI values measured by the proposed method were strongly and positively correlated with those measured by professional instruments. Meanwhile, the proposed algorithm was able to recognize the potholes/humps that the bicycle passed. The proposed method is useful for measuring the surface roughness of roads that are not accessible for professional instruments, such as pedestrian and cycle lanes. This work enables us to further study the feasibility of crowdsourcing road surface roughness with bicycle-mounted smartphones. PMID:29562731

  5. Road safety practices among commercial motorcyclists in a rural town in Nigeria: implications for health education.

    Science.gov (United States)

    Amoran, O E; Eme, Owoaje; Giwa, O A; Gbolahan, O B

    This cross-sectional, community-based study was carried out among commercial motorcyclists in Igboora. All the commercial motor parks in Igboora were visited and all the commercial motorcyclists who consented to participate in the study were interviewed. Information on the respondents' socio-demographic characteristics, and the practice of road safety measures was collected using an interviewer administered questionnaire. A total of 299 motorcyclists were interviewed. All (100%) of them were males. The mean age of the respondents was 27.4 +/- 7.4 years. One hundred eighty-two (60.7%) of the motorcyclists had the correct knowledge of the purpose of Highway Code. Only 70 (23.3%) could recognize more than half of the currently used road safety codes and 47 (15.7%) obey these road safety codes more than half of the time they see it. Only 183 (61.2%) of them had a driving license and 72 (24.1%) were able to produce these licenses on demand. All (100%) of the respondents did not use any protective helmet. Those who have longer years of working experience, higher level of education and higher knowledge of the safety codes practice it more regularly (r = 0.198, p = 0.001, chi2= 9.31, p = 0.025, and r = 0.28, p = 0.001 respectively). One hundred thirty-six (45.5%) have been involved in at least one accident in the preceding year. The overall incidence of road traffic accident was 2.16 per 1,000. There was however on statistically significant association between the practice of road safety codes and the occurrence of road traffic accidents (chi2= 0.176, p = 0.916). The study shows that the practice of road safety measures was low in this rural Nigerian community and was not associated with the incidence of road traffic accidents. Introducing road safety education particularly targeted at educating the motorcyclists on the importance and practice of road safety measures would lead to an increase in the practice of the safety measures and hopefully a reduction in the incidence

  6. Road user behaviour changes following a self-explaining roads intervention.

    Science.gov (United States)

    Mackie, Hamish W; Charlton, Samuel G; Baas, Peter H; Villasenor, Pablo C

    2013-01-01

    The self-explaining roads (SER) approach uses road designs that evoke correct expectations and driving behaviours from road users to create a safe and user-friendly road network. Following the implementation of an SER process and retrofitting of local and collector roads in a suburb within Auckland City, lower speeds on local roads and less variation in speed on both local and collector roads were achieved, along with a closer match between actual and perceived safe speeds. Preliminary analyses of crash data shows that the project has resulted in a 30% reduction crash numbers and an 86% reduction in crash costs per annum, since the road changes were completed. In order to further understand the outcomes from this project, a study was carried out to measure the effects of the SER intervention on the activity and behaviour of all road users. Video was collected over nine separate days, at nine different locations, both before and after SER construction. Road user behaviour categories were developed for all potential road users at different location types and then used to code the video data. Following SER construction, on local roads there was a relatively higher proportion of pedestrians, less uniformity in vehicle lane keeping and less indicating by motorists along with less through traffic, reflecting a more informal/low speed local road environment. Pedestrians were less constrained on local roads following SER construction, possibly reflecting a perceptually safer and more user-friendly environment. These behaviours were not generally evident on collector roads, a trend also shown by the previous study of speed changes. Given that one of the objectives of SER is to match road user behaviour with functionally different road categories, the road user behaviour differences demonstrated on different road types within the SER trial area provides further reinforcement of a successful SER trial. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. a Geographic Weighted Regression for Rural Highways Crashes Modelling Using the Gaussian and Tricube Kernels: a Case Study of USA Rural Highways

    Science.gov (United States)

    Aghayari, M.; Pahlavani, P.; Bigdeli, B.

    2017-09-01

    Based on world health organization (WHO) report, driving incidents are counted as one of the eight initial reasons for death in the world. The purpose of this paper is to develop a method for regression on effective parameters of highway crashes. In the traditional methods, it was assumed that the data are completely independent and environment is homogenous while the crashes are spatial events which are occurring in geographic space and crashes have spatial data. Spatial data have spatial features such as spatial autocorrelation and spatial non-stationarity in a way working with them is going to be a bit difficult. The proposed method has implemented on a set of records of fatal crashes that have been occurred in highways connecting eight east states of US. This data have been recorded between the years 2007 and 2009. In this study, we have used GWR method with two Gaussian and Tricube kernels. The Number of casualties has been considered as dependent variable and number of persons in crash, road alignment, number of lanes, pavement type, surface condition, road fence, light condition, vehicle type, weather, drunk driver, speed limitation, harmful event, road profile, and junction type have been considered as explanatory variables according to previous studies in using GWR method. We have compered the results of implementation with OLS method. Results showed that R2 for OLS method is 0.0654 and for the proposed method is 0.9196 that implies the proposed GWR is better method for regression in rural highway crashes.

  8. A GEOGRAPHIC WEIGHTED REGRESSION FOR RURAL HIGHWAYS CRASHES MODELLING USING THE GAUSSIAN AND TRICUBE KERNELS: A CASE STUDY OF USA RURAL HIGHWAYS

    Directory of Open Access Journals (Sweden)

    M. Aghayari

    2017-09-01

    Full Text Available Based on world health organization (WHO report, driving incidents are counted as one of the eight initial reasons for death in the world. The purpose of this paper is to develop a method for regression on effective parameters of highway crashes. In the traditional methods, it was assumed that the data are completely independent and environment is homogenous while the crashes are spatial events which are occurring in geographic space and crashes have spatial data. Spatial data have spatial features such as spatial autocorrelation and spatial non-stationarity in a way working with them is going to be a bit difficult. The proposed method has implemented on a set of records of fatal crashes that have been occurred in highways connecting eight east states of US. This data have been recorded between the years 2007 and 2009. In this study, we have used GWR method with two Gaussian and Tricube kernels. The Number of casualties has been considered as dependent variable and number of persons in crash, road alignment, number of lanes, pavement type, surface condition, road fence, light condition, vehicle type, weather, drunk driver, speed limitation, harmful event, road profile, and junction type have been considered as explanatory variables according to previous studies in using GWR method. We have compered the results of implementation with OLS method. Results showed that R2 for OLS method is 0.0654 and for the proposed method is 0.9196 that implies the proposed GWR is better method for regression in rural highway crashes.

  9. Optimal Corridor Selection for a Road Space Management Strategy: Methodology and Tool

    Directory of Open Access Journals (Sweden)

    Sushant Sharma

    2017-01-01

    Full Text Available Nationwide, there is a growing realization that there are valuable benefits to using the existing roadway facilities to their full potential rather than expanding capacity in a traditional way. Currently, state DOTs are looking for cost-effective transportation solutions to mitigate the growing congestion and increasing funding gaps. Innovative road space management strategies like narrowing of multiple lanes (three or more and shoulder width to add a lane enhance the utilization while eliminating the costs associated with constructing new lanes. Although this strategy (among many generally leads to better mobility, identifying optimal corridors is a challenge and may affect the benefits. Further, there is a likelihood that added capacity may provide localized benefits, at the expense of system level performance measures (travel time and crashes because of the relocation of traffic operational bottlenecks. This paper develops a novel transportation programming and investment decision method to identify optimal corridors for adding capacity in the network by leveraging lane widths. The methodology explicitly takes into consideration the system level benefits and safety. The programming compares two conflicting objectives of system travel time and safety benefits to find an optimal solution.

  10. Macroscopic and microscopic analyses of managed lanes on freeway facilities in South Florida

    Directory of Open Access Journals (Sweden)

    Soheil Sajjadi

    2017-02-01

    The results of the study indicate that the percent drop in capacity for the one-lane FP site is 7.6% while the flow did not substantially change after the breakdown in the two-lane FP site. The research findings also include guidelines for simulating the breakdown events and calibrating one-lane and two-lane managed lane facilities in VISSIM microsimulation software. The Wiedemann car-following parameters (CC0 = 3.9 ft, CC1 = 1.9 s, CC2 = 26.25 ft, CC4 = −0.35, and CC5 = 0.35 provided the best fit for the one-lane FP site, while the combination (CC0 = 4.92 ft, CC1 = 1.9 s, CC2 = 39.37 ft, CC4 = −0.7, and CC5 = 0.7 parameters is recommended for the two-lane FP site.

  11. Motorcycle lane-sharing : literature review.

    Science.gov (United States)

    2010-06-01

    This report examines the use of lane-sharing (also sometimes referred to as lane-splitting and filtering) nationally and internationally and includes discussions on motorcycle and driver (auto) safety, and the potential benefits of lane-sharing.

  12. Dynamic path planning for autonomous driving on various roads with avoidance of static and moving obstacles

    Science.gov (United States)

    Hu, Xuemin; Chen, Long; Tang, Bo; Cao, Dongpu; He, Haibo

    2018-02-01

    This paper presents a real-time dynamic path planning method for autonomous driving that avoids both static and moving obstacles. The proposed path planning method determines not only an optimal path, but also the appropriate acceleration and speed for a vehicle. In this method, we first construct a center line from a set of predefined waypoints, which are usually obtained from a lane-level map. A series of path candidates are generated by the arc length and offset to the center line in the s - ρ coordinate system. Then, all of these candidates are converted into Cartesian coordinates. The optimal path is selected considering the total cost of static safety, comfortability, and dynamic safety; meanwhile, the appropriate acceleration and speed for the optimal path are also identified. Various types of roads, including single-lane roads and multi-lane roads with static and moving obstacles, are designed to test the proposed method. The simulation results demonstrate the effectiveness of the proposed method, and indicate its wide practical application to autonomous driving.

  13. Calculation of the temperature of asphalt concrete at making the joints of multilane road pavement of non-rigid type

    Directory of Open Access Journals (Sweden)

    Giyasov Botir Iminzhonovich

    2015-03-01

    Full Text Available The construction quality of road surface of non-rigid type essentially depend on providing the temperature regimes in the process of laying and packing of hot asphalt concrete mixtures. In order to provide the required characteristics of asphalt concrete due to the surface width it is necessary to provide the temperature regimes of hot asphalt concrete mixture in the zones of lane connection. The hot mixture is promptly cooling right after laying within several minutes, which results, according to the construction technology and the specific conditions of work production, in temperature abuse of the mixture at joints of the lanes at packing. The authors present the analysis of the technology of arranging multilane road surface by one paver with the possibility of heating the surface lane edge with the temperature of the adjacent lane. The results of the studies of the production conditions effect on the temperature of edge heating of the previously laid lanes, and the time required to achieve the maximum heating temperature depending on the relative thickness of coating layers.

  14. The effectiveness of lane departure warning systems-A reduction in real-world passenger car injury crashes.

    Science.gov (United States)

    Sternlund, Simon; Strandroth, Johan; Rizzi, Matteo; Lie, Anders; Tingvall, Claes

    2017-02-17

    The objective of this study was to estimate the safety benefits of in vehicle lane departure warning (LDW) and lane keeping aid (LKA) systems in reducing relevant real-world passenger car injury crashes. The study used an induced exposure method, where LDW/LKA-sensitive and nonsensitive crashes were compared for Volvo passenger cars equipped with and without LDW/LKA systems. These crashes were matched by car make, model, model year, and technical equipment; that is, low-speed autonomous emergency braking (AEB) called City Safety (CS). The data were extracted from the Swedish Traffic Accident Data Acquisition database (STRADA) and consisted of 1,853 driver injury crashes that involved 146 LDW-equipped cars, 11 LKA-equipped cars, and 1,696 cars without LDW/LKA systems. The analysis showed a positive effect of the LDW/LKA systems in reducing lane departure crashes. The LDW/LKA systems were estimated to reduce head-on and single-vehicle injury crashes on Swedish roads with speed limits between 70 and 120 km/h and with dry or wet road surfaces (i.e., not covered by ice or snow) by 53% with a lower limit of 11% (95% confidence interval [CI]). This reduction corresponded to a reduction of 30% with a lower limit of 6% (95% CI) for all head-on and single-vehicle driver injury crashes (including all speed limits and all road surface conditions). LDW/LKA systems were estimated to lower the driver injury risk in crash types that the systems are designed to prevent; that is, head-on and single-vehicle crashes. Though these are important findings, they were based on a small data set. Therefore, further research is desirable to evaluate the effectiveness of LDW/LKA systems under real-world conditions and to differentiate the effectiveness between technical solutions (i.e., LDW and LKA) proposed by different manufacturers.

  15. Guidebook for Providing Economic Assistance at the Tactical Level During Stability Operations

    Science.gov (United States)

    2009-01-01

    roads with single-lane bridges are ade- quate to connect rural villages to major roads where traffic is light. Asphalt or concrete is suit- able for...updated annually and can be purchased directly from the World Bank through the inter- net site at http://publications.worldbank.org/ ecommerce /catalog...help ex-combatants and rural workers to start their own businesses. Most ex-combatants and unskilled civilian laborers do not have the business

  16. Guidebook for Supporting Economic Development in Stability Operations

    Science.gov (United States)

    2009-01-01

    purpose. Gravel roads with single-lane bridges are ade- quate to connect rural villages to major roads where traffic is light. Asphalt or concrete is suit...It is updated annually and can be purchased directly from the World Bank through the inter- net site at http://publications.worldbank.org/ ecommerce ...providing grants to help ex-combatants and rural workers to start their own businesses. Most ex-combatants and unskilled civilian laborers do not have the

  17. Lie Group Classification of a Generalized Lane-Emden Type System in Two Dimensions

    Directory of Open Access Journals (Sweden)

    Motlatsi Molati

    2012-01-01

    Full Text Available The aim of this work is to perform a complete Lie symmetry classification of a generalized Lane-Emden type system in two dimensions which models many physical phenomena in biological and physical sciences. The classical approach of group classification is employed for classification. We show that several cases arise in classifying the arbitrary parameters, the forms of which include amongst others the power law nonlinearity, and exponential and quadratic forms.

  18. Classification of busses and lorries in an automatic road toll system

    OpenAIRE

    Jarl, Adam

    2003-01-01

    An automatic road toll system enables the passing vehicles to change lanes and no stop is needed for payment. Because of different weight of personal cars, busses, lorries (trucks) and other vehicles, they affect the road in different ways. It is of interest to categorize the vehicles into different classes depending of their weight so that the right fee can be set. An automatic road toll system developed by Combitech Traffic Systems AB (now Kapsch TrafficCom AB), Joenkoping, Sweden, classifi...

  19. Modelling traffic flows with intelligent cars and intelligent roads

    NARCIS (Netherlands)

    van Arem, Bart; Tampere, Chris M.J.; Malone, Kerry

    2003-01-01

    This paper addresses the modeling of traffic flows with intelligent cars and intelligent roads. It will describe the modeling approach MIXIC and review the results for different ADA systems: Adaptive Cruise Control, a special lane for Intelligent Vehicles, cooperative following and external speed

  20. Bayesian road safety analysis: incorporation of past evidence and effect of hyper-prior choice.

    Science.gov (United States)

    Miranda-Moreno, Luis F; Heydari, Shahram; Lord, Dominique; Fu, Liping

    2013-09-01

    This paper aims to address two related issues when applying hierarchical Bayesian models for road safety analysis, namely: (a) how to incorporate available information from previous studies or past experiences in the (hyper) prior distributions for model parameters and (b) what are the potential benefits of incorporating past evidence on the results of a road safety analysis when working with scarce accident data (i.e., when calibrating models with crash datasets characterized by a very low average number of accidents and a small number of sites). A simulation framework was developed to evaluate the performance of alternative hyper-priors including informative and non-informative Gamma, Pareto, as well as Uniform distributions. Based on this simulation framework, different data scenarios (i.e., number of observations and years of data) were defined and tested using crash data collected at 3-legged rural intersections in California and crash data collected for rural 4-lane highway segments in Texas. This study shows how the accuracy of model parameter estimates (inverse dispersion parameter) is considerably improved when incorporating past evidence, in particular when working with the small number of observations and crash data with low mean. The results also illustrates that when the sample size (more than 100 sites) and the number of years of crash data is relatively large, neither the incorporation of past experience nor the choice of the hyper-prior distribution may affect the final results of a traffic safety analysis. As a potential solution to the problem of low sample mean and small sample size, this paper suggests some practical guidance on how to incorporate past evidence into informative hyper-priors. By combining evidence from past studies and data available, the model parameter estimates can significantly be improved. The effect of prior choice seems to be less important on the hotspot identification. The results show the benefits of incorporating prior

  1. Road Fatality Model Based on Over-Dispersion Data Along Federal Route F0050

    Directory of Open Access Journals (Sweden)

    Musa Wan Zahidah

    2017-01-01

    Full Text Available According to The World Health Ranking 2011 has ranked Malaysia as 20th in its list of countries with the most deaths caused by road accidents. Road accidents also have been identified as the prime cause of death in Malaysia after the heart disease, stroke, influenza and pneumonia. To date, previous researches from Malaysian Institute of Road Safety (MIROS have reported that averages of 18 people were killed on Malaysian road daily. There are many kinds of models that have been developed in modelling the circumstance of accidents. The most widely applied was Poisson and Negative Binomial regression models while Zeroinflated Poisson and Zero-inflated Negative Binomial are the modification of Poisson and Negative Binomials regression models. This study interested to focus on road F0050 as statistic data from Royal Malaysian Police 2014 list F0050 as one of the high accident road in Malaysia from kilometre 0 until kilometre 58. R programming was chose to analyse the relationship between road fatality and its factor (annual average daily traffic (AADT, speed, shoulder width, lane width. Negative binomial and Zero-inflated negative binomial (ZINB were shown to be preferred modelling methods for this study. Significant positive relationships were also identified between road fatality and annual average daily traffic (AADT and lane width. This relationship can be a helpful support to the decision making of accident management for road F0050.

  2. A hybrid clustering and classification approach for predicting crash injury severity on rural roads.

    Science.gov (United States)

    Hasheminejad, Seyed Hessam-Allah; Zahedi, Mohsen; Hasheminejad, Seyed Mohammad Hossein

    2018-03-01

    As a threat for transportation system, traffic crashes have a wide range of social consequences for governments. Traffic crashes are increasing in developing countries and Iran as a developing country is not immune from this risk. There are several researches in the literature to predict traffic crash severity based on artificial neural networks (ANNs), support vector machines and decision trees. This paper attempts to investigate the crash injury severity of rural roads by using a hybrid clustering and classification approach to compare the performance of classification algorithms before and after applying the clustering. In this paper, a novel rule-based genetic algorithm (GA) is proposed to predict crash injury severity, which is evaluated by performance criteria in comparison with classification algorithms like ANN. The results obtained from analysis of 13,673 crashes (5600 property damage, 778 fatal crashes, 4690 slight injuries and 2605 severe injuries) on rural roads in Tehran Province of Iran during 2011-2013 revealed that the proposed GA method outperforms other classification algorithms based on classification metrics like precision (86%), recall (88%) and accuracy (87%). Moreover, the proposed GA method has the highest level of interpretation, is easy to understand and provides feedback to analysts.

  3. Improving the Sustainability of Transportation: Environmental and Functional Benefits of Right Turn By-Pass Lanes at Roundabouts

    Directory of Open Access Journals (Sweden)

    Marco Guerrieri

    2015-05-01

    Full Text Available The functional performances of conventional roundabouts (single-lane and multi-lane and innovative roundabouts (spiral, flower, C and turbo can be improved through right-turn bypass lanes controlled by stop, yield or free-flow signs. The article presents evaluations of the emissions of air pollutants (carbon dioxide, nitrogen oxides, particle pollution (PM10 and PM2.5, fuel consumption and construction, management, energetic and environmental costs in roundabouts without or with bypass lanes (controlled by stop, yield or free-flow. The suggested methodology has a general character and can be applied as a multi-parametric criterion for choosing road intersections, although, in the present paper, it has been employed only for a case study. For the aims of this research, we employed recent closed-form formulations to determine roundabout performances; moreover, we used the COPERT IV® software to estimate air emissions in nine different types of vehicles. Numerous traffic simulations were carried out. The variation in the maximum hourly traffic Qmax and annual traffic QTOT provided the appropriate domains of the examined geometric layouts, both in functional and environmental terms and with regard to generalized costs, estimated for a 10-year period. It resulted that the introduction of right-turn bypasses in all arms of conventional roundabouts with a one ring lane and one lane at the entries (single-lane roundabouts is the most cost-effective when the flows entering the roundabout are higher than Qmax = 2000 veh/h. Moreover, free-flow bypass lanes always provide greater capacity and lower delays than stop- or yield-signaled bypasses. However, with extremely high Qmax values, stop-controlled bypasses guarantee lower fuel consumption, while those with a yield sign lower total costs.

  4. Multi-lane Changing Model with Coupling Driving Intention and Inclination

    Directory of Open Access Journals (Sweden)

    Jiangfeng Wang

    2017-04-01

    Full Text Available Considering the impact of drivers’ psychology and behaviour, a multi-lane changing model coupling driving intention and inclination is proposed by introducing two quantitative indices of intention: strength of lane changing and risk factor. According to the psychological and behavioural characteristics of aggressive drivers and conservative drivers, the safety conditions for lane changing are designed respectively. The numerical simulations show that the proposed model is suitable for describing the traffic flow with frequent lane changing, which is more consistent with the driving behaviour of drivers in China. Compared with symmetric two-lane cellular automata (STCA model, the proposed model can improve the average speed of vehicles by 1.04% under different traffic demands when aggressive drivers are in a higher proportion (the threshold of risk factor is 0.4. When the risk factor increases, the average speed shows the polarization phenomenon with the average speed slowing down in big traffic demand. The proposed model can reflect the relationship among density, flow, and speed, and the risk factor has a significant impact on density and flow.

  5. Egocentric framing - one way people may fail in a switch dilemma: evidence from excessive lane switching.

    Science.gov (United States)

    Navon, David; Kaplan, Todd R; Kasten, Ronen

    2013-11-01

    To study switching behavior, an experiment mimicking the state of a driver on the road was conducted. In each trial participants were given a chance to switch lanes. Despite the fact that lane switching had no sound rational basis, participants often switched lanes when the speed of driving in their lane on the previous trial was relatively slow. That tendency was discerned even when switching behavior had been sparsely reinforced, and was especially marked in almost a third of the participants, who manifested it consistently. The findings illustrate a type of behavior occurring in various contexts (e.g., stocks held in a portfolio, conduct pertinent for residual life expectancy, supermarket queues). We argue that this behavior may be due to a fallacy reminiscent of that arising in the well-known "envelopes problem", in which each of two players holds a sum of money of which she knows nothing about except that it is either half or twice the amount held by the other player. Players may be paradoxically tempted to exchange assets, since an exchange fallaciously appears to always yield an expected value greater than whatever is regarded as the player's present assets. We argue that the fallacy is due to egocentrically framing the problem as if the "amount I have" is definite, albeit unspecified, and shows that framing the paradox acentrically instead eliminates the incentive to exchange assets. A possible psychological source for the human disposition to frame problems in a way that inflates expected gain is discussed. Finally, a heuristic meant to avert the source of the fallacy is proposed. © 2013.

  6. Lane Detection in Video-Based Intelligent Transportation Monitoring via Fast Extracting and Clustering of Vehicle Motion Trajectories

    Directory of Open Access Journals (Sweden)

    Jianqiang Ren

    2014-01-01

    Full Text Available Lane detection is a crucial process in video-based transportation monitoring system. This paper proposes a novel method to detect the lane center via rapid extraction and high accuracy clustering of vehicle motion trajectories. First, we use the activity map to realize automatically the extraction of road region, the calibration of dynamic camera, and the setting of three virtual detecting lines. Secondly, the three virtual detecting lines and a local background model with traffic flow feedback are used to extract and group vehicle feature points in unit of vehicle. Then, the feature point groups are described accurately by edge weighted dynamic graph and modified by a motion-similarity Kalman filter during the sparse feature point tracking. After obtaining the vehicle trajectories, a rough k-means incremental clustering with Hausdorff distance is designed to realize the rapid online extraction of lane center with high accuracy. The use of rough set reduces effectively the accuracy decrease, which results from the trajectories that run irregularly. Experimental results prove that the proposed method can detect lane center position efficiently, the affected time of subsequent tasks can be reduced obviously, and the safety of traffic surveillance systems can be enhanced significantly.

  7. The effect of rural road transport infrastructure on smallholder farmers’ agricultural productivity in Horro Guduru Wollega Zone, Western Ethiopia

    Directory of Open Access Journals (Sweden)

    Sileshi Tamene

    2017-04-01

    Full Text Available This study was carried out to examine access to rural road infrastructure and its effects on smallholder farmers’ agricultural productivity in Horro Guduru Wollega Zone, Western Ethiopia. A three stage random sampling technique was employed to select 500 farming households in the study area and data was collected on their socio-economic and farm specific characteristics. The collected data was analyzed using descriptive statistics and stepwise multiple regression analysis. The result of multiple regression model used revealed that distance to major market is important in predicting agricultural productivity of smallholder farmers at 5% levels of probability in Abe Dongoro, Amuru and Hababo Guduru districts. Ownership of intermediate means of transport was also found to influence agricultural productivity in Horro, Amuru and Hababo Guduru districts (p = 0.05. Further analysis of the regression model showed a significant negative correlation between distance to nearest all weather roads and distance to zonal head quarter on one hand and agricultural productivity on the other hand in Abe Dongoro, Hababo Guduru and Amuru districts. Rural kebeles of Abe Dongoro and Amuru districts which has vast agricultural potential were found to be the most inaccessible in Horro Guduru Wollega Zone. It is therefore suggested that interventions in the transport sector should include provision of rural roads as well as measures that will help improve vehicle supply in rural areas. An attempt has to be done also to increase the use of intermediate means of transport to ease agricultural inputs and outputs mobility and farm access.

  8. Local resource based approach to maintaining and preserving rural local access roads assets: Siyatentela institutional framework and governance case study discourses

    CSIR Research Space (South Africa)

    Chakwizira, J

    2010-10-01

    Full Text Available and other development agencies focusing on the use of appropriate technologies for civil construction be it in the road, transport, water, agriculture or environmental sectors (World Bank 2001; ILO, 2002; Clegg, 2003). The seminal study conducted... and contribution of local resource based approach to rural and community access roads requires a review of the labour based initiatives in the road, transport and infrastructure sub-sector. An apt statement that captures the essence of building local community...

  9. FROM THE ROAD SIGN TO THE MAP: 3D MODELING IN SUPPORT OF THE URBAN AND RURAL ROAD CONDITIONS

    Directory of Open Access Journals (Sweden)

    A. Palummo

    2017-05-01

    Full Text Available Unmanned Aerial Vehicles (UAV, commonly known as a drone, and an Unmanned Aircraft Systems (UAS have been spreading on a massive scale during the last few years, especially for civilian use. And this situation can have significant repercussions on the ways and purposes with which we make photogrammetry nowadays. In this brief article we take into account the italian road signs as a case study on which to apply the new potential of photogrammetry realized with the aid of drones. Our main purpose is to achieve a specific method which allows the calculation of centimeter precision measurements of solids reconstructed for a mapping of (public and private road signs which require verification or replacement in urban, peri-urban and rural areas. Our hope is that this new approach to photogrammetry may arise opportunities for dialogue with policy makers especially where the usefulness of mapping could also appear predictive with respect to recurrent issues before they become consolidated.

  10. Improvement of driving safety in road traffic system

    Science.gov (United States)

    Li, Ke-Ping; Gao, Zi-You

    2005-05-01

    A road traffic system is a complex system in which humans participate directly. In this system, human factors play a very important role. In this paper, a kind of control signal is designated at a given site (i.e., signal point) of the road. Under the effect of the control signal, the drivers will decrease their velocities when their vehicles pass the signal point. Our aim is to transit the traffic flow states from disorder to order and then improve the traffic safety. We have tested this technique for the two-lane traffic model that is based on the deterministic Nagel-Schreckenberg (NaSch) traffic model. The simulation results indicate that the traffic flow states can be transited from disorder to order. Different order states can be observed in the system and these states are safer.

  11. LANES - LOCAL AREA NETWORK EXTENSIBLE SIMULATOR

    Science.gov (United States)

    Gibson, J.

    1994-01-01

    The Local Area Network Extensible Simulator (LANES) provides a method for simulating the performance of high speed local area network (LAN) technology. LANES was developed as a design and analysis tool for networking on board the Space Station. The load, network, link and physical layers of a layered network architecture are all modeled. LANES models to different lower-layer protocols, the Fiber Distributed Data Interface (FDDI) and the Star*Bus. The load and network layers are included in the model as a means of introducing upper-layer processing delays associated with message transmission; they do not model any particular protocols. FDDI is an American National Standard and an International Organization for Standardization (ISO) draft standard for a 100 megabit-per-second fiber-optic token ring. Specifications for the LANES model of FDDI are taken from the Draft Proposed American National Standard FDDI Token Ring Media Access Control (MAC), document number X3T9.5/83-16 Rev. 10, February 28, 1986. This is a mature document describing the FDDI media-access-control protocol. Star*Bus, also known as the Fiber Optic Demonstration System, is a protocol for a 100 megabit-per-second fiber-optic star-topology LAN. This protocol, along with a hardware prototype, was developed by Sperry Corporation under contract to NASA Goddard Space Flight Center as a candidate LAN protocol for the Space Station. LANES can be used to analyze performance of a networking system based on either FDDI or Star*Bus under a variety of loading conditions. Delays due to upper-layer processing can easily be nullified, allowing analysis of FDDI or Star*Bus as stand-alone protocols. LANES is a parameter-driven simulation; it provides considerable flexibility in specifying both protocol an run-time parameters. Code has been optimized for fast execution and detailed tracing facilities have been included. LANES was written in FORTRAN 77 for implementation on a DEC VAX under VMS 4.6. It consists of two

  12. Trajectory generation for an on-road autonomous vehicle

    Science.gov (United States)

    Horst, John; Barbera, Anthony

    2006-05-01

    We describe an algorithm that generates a smooth trajectory (position, velocity, and acceleration at uniformly sampled instants of time) for a car-like vehicle autonomously navigating within the constraints of lanes in a road. The technique models both vehicle paths and lane segments as straight line segments and circular arcs for mathematical simplicity and elegance, which we contrast with cubic spline approaches. We develop the path in an idealized space, warp the path into real space and compute path length, generate a one-dimensional trajectory along the path length that achieves target speeds and positions, and finally, warp, translate, and rotate the one-dimensional trajectory points onto the path in real space. The algorithm moves a vehicle in lane safely and efficiently within speed and acceleration maximums. The algorithm functions in the context of other autonomous driving functions within a carefully designed vehicle control hierarchy.

  13. A New Approach to Lane Guidance Systems

    OpenAIRE

    Eidehall, Andreas; Pohl, Jochen; Gustafsson, Fredrik

    2005-01-01

    This paper presents a new automotive safety function called Emergency Lane Assist (ELA). ELA combines conventional lane guidance systems with a threat assessment module that tries to activate and deactivate the lane guidance interventions according to the actual risk level of lane departure. The goal is to only prevent dangerous lane departure manoeuvres. Such a threat assessment algorithm is dependent on detailed information about the vehicle surroundings, i.e., positions and motion of other...

  14. Applicability of models to estimate traffic noise for urban roads.

    Science.gov (United States)

    Melo, Ricardo A; Pimentel, Roberto L; Lacerda, Diego M; Silva, Wekisley M

    2015-01-01

    Traffic noise is a highly relevant environmental impact in cities. Models to estimate traffic noise, in turn, can be useful tools to guide mitigation measures. In this paper, the applicability of models to estimate noise levels produced by a continuous flow of vehicles on urban roads is investigated. The aim is to identify which models are more appropriate to estimate traffic noise in urban areas since several models available were conceived to estimate noise from highway traffic. First, measurements of traffic noise, vehicle count and speed were carried out in five arterial urban roads of a brazilian city. Together with geometric measurements of width of lanes and distance from noise meter to lanes, these data were input in several models to estimate traffic noise. The predicted noise levels were then compared to the respective measured counterparts for each road investigated. In addition, a chart showing mean differences in noise between estimations and measurements is presented, to evaluate the overall performance of the models. Measured Leq values varied from 69 to 79 dB(A) for traffic flows varying from 1618 to 5220 vehicles/h. Mean noise level differences between estimations and measurements for all urban roads investigated ranged from -3.5 to 5.5 dB(A). According to the results, deficiencies of some models are discussed while other models are identified as applicable to noise estimations on urban roads in a condition of continuous flow. Key issues to apply such models to urban roads are highlighted.

  15. Miami, FL I-95 express lanes.

    Science.gov (United States)

    2013-01-01

    The Miami-Ft. Lauderdale region is creating a 22-mile managed-lane facility, : including HOT lanes on I-95, between I-395 and I-595, with a longer term goal of : providing a network of managed lanes throughout the congested region. Freeflowing : cond...

  16. Social dilemma structures hidden behind traffic flow with lane changes

    International Nuclear Information System (INIS)

    Tanimoto, Jun; Kukida, Shinji; Hagishima, Aya

    2014-01-01

    Aiming to merge traffic flow analysis with evolutionary game theory, we investigated the question of whether such structures can be formed from frequent lane changes in usual traffic flow without any explicit bottlenecks. In our model system, two classes of driver-agents coexist: C-agents (cooperative strategy) always remain in the lane they are initially assigned, whereas D-agents (defective strategy) try to change lanes to move ahead. In relatively high-density flows, such as the metastable and high-density phases, we found structures that correspond to either n-person prisoner dilemma (n-PD) games or quasi-PD games. In these situations, lane changes by D-agents create heavy traffic jams that reduce social efficiency. (paper)

  17. Recognizablility of rural roads in the Netherlands.

    NARCIS (Netherlands)

    Aarts, L.T. & Davidse, R.J.

    2008-01-01

    In the Netherlands, the Sustainable Safety vision is an important guide in improving road safety. It is considered that the road environment shouldconform to the expectations of road users in order to prevent errors thatcould lead to road crashes. These expectations are based on the characteristics

  18. Perceiving and Acting on Complex Affordances: How Children and Adults Bicycle across Two Lanes of Opposing Traffic

    Science.gov (United States)

    Grechkin, Timofey Y.; Chihak, Benjamin J.; Cremer, James F.; Kearney, Joseph K.; Plumert, Jodie M.

    2013-01-01

    This investigation examined how children and adults negotiate a challenging perceptual-motor problem with significant real-world implications--bicycling across two lanes of opposing traffic. Twelve- and 14-year-olds and adults rode a bicycling simulator through an immersive virtual environment. Participants crossed intersections with continuous…

  19. Runoff and sediment yield from rural roads, trails and settlements in the upper Konto catchment, East Java, Indonesia

    Science.gov (United States)

    Rijsdijk, Anton; Sampurno Bruijnzeel, L. A.; Sutoto, C. Kukuh

    2007-06-01

    The potential importance of roads and settlements for the generation of storm runoff and sediment in tropical steeplands is increasingly recognised but rarely quantified. This paper presents runoff and sediment yield data for a cobbled and an unpaved road section, two large unbounded settlement plots, and several trails draining residential areas or terraced fields in a volcanic upland catchment in East Java. In addition, the sediment yield of major landslides associated with roads was quantified. The unpaved road section exhibited an average runoff coefficient of about 65% and yielded about 7 kg m - 2 yr - 1 of sediment. Both the runoff coefficient and the sediment yield for the cobbled road section (plus adjacent yards) were lower (38% and 1.9 kg m - 2 yr - 1 ). Sediment output from a 4160-m 2 hillside plot including a network of trails draining terraced fields (for which runoff and sediment outputs were shown to be negligible) was similar to that for the cobbled road (2-3 kg m - 2 yr - 1 depending on rainfall). However, a much higher value was obtained when the overall soil loss from the plot was expressed per square metre of trail surface area (ca. 42 kg m - 2 yr - 1 ) whereas the associated trail runoff coefficient was about 70%. The results obtained for several trails and large unbounded plots draining residential areas at two locations were less extreme (runoff coefficients of 24-43%; soil loss 1.3-3.5 kg m - 2 yr - 1 ). Landsliding occurred mainly at the end of the rainy season (March) and was estimated to have contributed ca. 2365 m 3 of sediment to the main road network during the 1988/89 wet season vs. ca. 905 m 3 in 1989/90 and only ca. 150 m 3 in 2000/01. It is concluded that, despite their relatively small areal extent (5% in the study area), rural roads, trails and settlements are significant producers of runoff and sediment at the catchment scale and should be included in watershed management programmes designed to reduce catchment sediment yields

  20. Rebound Attack on the Full LANE Compression Function

    DEFF Research Database (Denmark)

    Matusiewicz, Krystian; Naya-Plasencia, Maria; Nikolic, Ivica

    2009-01-01

    In this work, we apply the rebound attack to the AES based SHA-3 candidate Lane. The hash function Lane uses a permutation based compression function, consisting of a linear message expansion and 6 parallel lanes. In the rebound attack on Lane, we apply several new techniques to construct...... a collision for the full compression function of Lane-256 and Lane-512. Using a relatively sparse truncated differential path, we are able to solve for a valid message expansion and colliding lanes independently. Additionally, we are able to apply the inbound phase more than once by exploiting the degrees...

  1. A Hybrid Vision-Map Method for Urban Road Detection

    Directory of Open Access Journals (Sweden)

    Carlos Fernández

    2017-01-01

    Full Text Available A hybrid vision-map system is presented to solve the road detection problem in urban scenarios. The standardized use of machine learning techniques in classification problems has been merged with digital navigation map information to increase system robustness. The objective of this paper is to create a new environment perception method to detect the road in urban environments, fusing stereo vision with digital maps by detecting road appearance and road limits such as lane markings or curbs. Deep learning approaches make the system hard-coupled to the training set. Even though our approach is based on machine learning techniques, the features are calculated from different sources (GPS, map, curbs, etc., making our system less dependent on the training set.

  2. Real driving at night - Predicting lane departures from physiological and subjective sleepiness

    NARCIS (Netherlands)

    Hallvig, D.; Anund, A.; Fors, C.; Kecklund, L.G.; Äkerstedt, T.

    2014-01-01

    Only limited information is available on how driving performance relates to physiological and subjective sleepiness on real roads. This relation was the focus of the present study. 33 volunteers drove for 90 min on a rural road during the afternoon and night in an instrumented car, while

  3. Implementation elements for conversion of general-purpose freeway lane into high-occupancy-vehicle lane

    Science.gov (United States)

    1997-01-01

    Conversion of a general-purpose freeway into a high-occupancy-vehicle (HOV) lane is an alternative to infrastructure addition for HOV system implementation. Research indicates that lane conversion is feasible technically if sufficient HOV usage and m...

  4. Characterizing on-road driving performance in individuals with traumatic brain injury who pass or fail an on-road driving assessment.

    Science.gov (United States)

    Stolwyk, Renerus J; Charlton, Judith L; Ross, Pamela E; Bédard, Michel; Marshall, Shawn; Gagnon, Sylvain; Gooden, James R; Ponsford, Jennie L

    2018-01-15

    To characterise on-road driving performance in individuals with traumatic brain injury who fail on-road driving assessment, compared with both those who pass assessment and healthy controls, and the injury and cognitive factors associated with driving performance. Cross-sectional. Forty eight participants with traumatic brain injury (Age M = 40.50 SD = 14.62, 77% male, post-traumatic amnesia days M = 28.74 SD =27.68) and 48 healthy matched controls completed a standardised on-road driving assessment in addition to cognitive measures. Individuals with traumatic brain injury who passed on-road driving assessment performed no differently from controls while individuals with traumatic brain injury who failed the assessment demonstrated significantly worse driving performance relative to controls across a range of driving manoeuvres and error types including observation of on-road environment, speed control, gap selection, lane position, following distance and basic car control. Longer time post-injury and reduced visual perception were both significantly correlated with reduced driving skills. This exploratory study indicated that drivers with traumatic brain injury who failed on-road assessment demonstrated a heterogeneous pattern of impaired driving manoeuvres, characterised by skill deficits across both operational (e.g., basic car control and lane position) and tactical domains (e.g., following distance, gap selection, and observation) of driving. These preliminary findings can be used for implementation of future driving assessments and rehabilitation programs. Implications for rehabilitation Clinicians should be aware that the majority of individuals with traumatic brain injury were deemed fit to resume driving following formal on-road assessment, despite having moderate to very severe traumatic brain injuries. Drivers with traumatic brain injury who failed an on-road assessment demonstrated a heterogeneous pattern of impaired skills including errors

  5. Heavy metal contents of road-deposited sediment along the urban-rural gradient around Beijing and its potential contribution to runoff pollution.

    Science.gov (United States)

    Zhao, Hongtao; Li, Xuyong; Wang, Xiaomei

    2011-09-01

    Understanding the contribution of road-deposited sediment (RDS) and its washoff process is essential for controlling urban runoff pollution. Ninety-seven RDS samples were collected along the urban-suburban-rural gradient from areas of five administrative units in the Beijing metropolitan region, including central urban (UCA), urban village (UVA), central suburban county (CSA), rural town (RTA), and rural village (RVA) areas. RDS washoff was evaluated with different particle sizes using a rainfall simulator. Heavy metal elements (i.e., Cr, Cu, Ni, Pb, and Zn) were estimated in both RDS and runoff samples. The RDS mass per unit area increased in the order UCA (21 ± 24 g/m(2)) ≈ CSA (20 ± 16 g/m(2)) runoff pollution contributions per unit area. Our findings imply that controlling the first flush in the UCA and CSA, and improving existing street cleaning methods and road surface conditions in the TRA, UVA, and RVA will be appropriate strategies for controlling runoff pollution from RDS.

  6. A comparative study of bike lane injuries.

    Science.gov (United States)

    Wee, Jung Hee; Park, Jeong Ho; Park, Kyu Nam; Choi, Seung Pill

    2012-02-01

    Because of the increased number of bicycle riders and governmental promotions, a recent increase in the construction of bicycle lanes has occurred. We aimed to characterize injuries specific to bicycle lane accidents by comparing them with injuries that occurred on regular roadways. On the basis of our findings, we provide suggestions on proper preventive strategies. We performed a retrospective study on 408 cases obtained between January 1, 2009, and December 31, 2010. Of these cases, 387 met the criterion that the location of the injury could be confirmed by telephone or via review of the patient's chart. Data regarding age, gender, Injury Severity Score, time of the accident, location of the accident, and other characteristics were collected. Data were analyzed using SPSS 12.0K. Of the 387 cases, 204 (52.7%) patients were injured in bicycle lanes and 183 (47.3%) were injured on regular roadways. Comparing cases of bicycle lane injuries and non-bicycle lane injuries, there were no differences in age, day of the week, season, or the time at which the accident occurred. Bicycle helmets were used more frequently in bicycle lane injuries (33.2% vs. 13.7%; p cases, falls (42.6%) and collisions with other vehicles (39.3%) were the most common causes of injury. Although the severity of injuries was slightly lower in bicycle lane cases, it was not significantly lower than non-bicycle lane cases. Although people are increasingly using bicycle lanes for safety, this study shows that they are not definitively safer. Therefore, improvements in the policies related to implementing bicycle lane safety are needed, for example, by enforcing the use of protective gear or preventing the use of bicycle lanes by pedestrians. More safety education programs are also needed. III.

  7. Effect of bike lane infrastructure improvements on ridership in one New Orleans neighborhood.

    Science.gov (United States)

    Parker, Kathryn M; Rice, Janet; Gustat, Jeanette; Ruley, Jennifer; Spriggs, Aubrey; Johnson, Carolyn

    2013-02-01

    Incorporating cycling into daily life is one way to increase physical activity. This study examined the impact of building new bike lanes in New Orleans to determine whether more people were cycling on the street and with the flow of traffic after bike lanes were built. Through direct observation of one intervention and two adjacent streets, observers counted cyclists riding on the street and sidewalk, with and against traffic, before and after installation of the lanes. Data were tallied separately for adults, children, males, females, and by race for each location. There was an increase in cyclists on all three streets after the installation of the bike lanes, with the largest increase on the street with the new lane. Additionally, the proportion of riders cycling with traffic increased after the lanes were striped. Bike lanes can have a positive impact in creating a healthy neighborhood.

  8. At the cross-roads: an on-road examination of driving errors at intersections.

    Science.gov (United States)

    Young, Kristie L; Salmon, Paul M; Lenné, Michael G

    2013-09-01

    A significant proportion of road trauma occurs at intersections. Understanding the nature of driving errors at intersections therefore has the potential to lead to significant injury reductions. To further understand how the complexity of modern intersections shapes behaviour of these errors are compared to errors made mid-block, and the role of wider systems failures in intersection error causation is investigated in an on-road study. Twenty-five participants drove a pre-determined urban route incorporating 25 intersections. Two in-vehicle observers recorded the errors made while a range of other data was collected, including driver verbal protocols, video, driver eye glance behaviour and vehicle data (e.g., speed, braking and lane position). Participants also completed a post-trial cognitive task analysis interview. Participants were found to make 39 specific error types, with speeding violations the most common. Participants made significantly more errors at intersections compared to mid-block, with misjudgement, action and perceptual/observation errors more commonly observed at intersections. Traffic signal configuration was found to play a key role in intersection error causation, with drivers making more errors at partially signalised compared to fully signalised intersections. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Deployment strategies of managed lanes on arterials.

    Science.gov (United States)

    2015-02-01

    This report investigates issues related to planning, financing, deployment, and operation of managed : lanes on arterials. In this report, a strategy for managed lanes refers to a combination of the managed : lane type, the design and implementation,...

  10. Aerometrics' laser-based lane-tracker sensor: engineering and on-the-road evaluation of advanced prototypes

    Science.gov (United States)

    Schuler, Carlos A.; Tapos, Francis M.; Alayleh, Mehyeddine M.; Bachalo, William D.

    1997-02-01

    Aerometrics initiated and continues on the development an innovative laser-diode based device that provides a warning signal when a motor-vehicle deviates from the center of the lane. The device is based on a sensor that scans the roadway on either side of the vehicle and determines the lateral position relative to the existing painted lines marking the lane. The principles of operation of the sensor, and the results of Aerometrics' early testing were presented last year in this forum. This paper presents Aerometrics' continuing efforts in bringing the technology to market. New prototypes have been developed and tested. Aerometrics' engineering efforts and the use of latest technologies have resulted in a 24-fold reduction in sensor volume when compared to their predecessors and similar reductions in weight. The current prototype measures less than 9 cm X 8 cm X 7 cm, and can be easily fit within the cavity of rear-view mirror holders used in most present-day vehicles. Also, advances in signal conditioning and processing have improved the reliability of the sensor. Results of continuing testing of the sensor will be presented.

  11. Road design and environment : best practice on self-explaining and forgiving roads. Deliverable D3 of the RiPCORD-iSEREST project (Road Infrastructure Safety Protection - Core-Research and Development for Road Safety in Europe; Increasing safety and reliability of secondary roads for a sustainable Surface Transport).

    NARCIS (Netherlands)

    Matena, S. Louwerse, W. Schermers, G. Vaneerdewegh, P. Pokorny, P. Gaitanidou, L. Elvik, R. & Cardoso, J.

    2009-01-01

    Main objective of work-package 3 of Ripcord-lserest was to collect information on best practices concerning the design of self-explaining and forgiving roads. In order to gain an overview on existing practises on road categorisation and the layout of typical rural roads a questionnaire survey had

  12. Lane Detection on the iPhone

    Science.gov (United States)

    Ren, Feixiang; Huang, Jinsheng; Terauchi, Mutsuhiro; Jiang, Ruyi; Klette, Reinhard

    A robust and efficient lane detection system is an essential component of Lane Departure Warning Systems, which are commonly used in many vision-based Driver Assistance Systems (DAS) in intelligent transportation. Various computation platforms have been proposed in the past few years for the implementation of driver assistance systems (e.g., PC, laptop, integrated chips, PlayStation, and so on). In this paper, we propose a new platform for the implementation of lane detection, which is based on a mobile phone (the iPhone). Due to physical limitations of the iPhone w.r.t. memory and computing power, a simple and efficient lane detection algorithm using a Hough transform is developed and implemented on the iPhone, as existing algorithms developed based on the PC platform are not suitable for mobile phone devices (currently). Experiments of the lane detection algorithm are made both on PC and on iPhone.

  13. Lupino Lane

    OpenAIRE

    Couderc, Jean-Jacques

    2015-01-01

    Henry George Lupino est né à Londres le 16 juin 1892 d’une famille d’acteurs d’origine italienne : les Lupino, célèbre troupe de smarionnettistes, avaient émigré dès le xviie siècle, puis s’étaient illustrés au music-hall. Le père, Henry Charles, épousa une Lane, famille célèbre de la scène anglaise, et eut deux fils : Henry George qui adopta comme pseudonyme les noms de ses deux géniteurs (Lupino Lane) et Wallace qui comme son frère fit une carrière cinématographique. Le petit Henry George s...

  14. Cross-border shipment route selection utilizing analytic hierarchy process (AHP method

    Directory of Open Access Journals (Sweden)

    Veeris Ammarapala

    2018-02-01

    Full Text Available Becoming a member of ASEAN Economic Community (AEC, Thailand expects a growth of cross-border trade with neighboring countries, especially the agricultural products shipment. To facilitate this, a number of strategies are set, such as the utilization of single check point, the Asian Highway (AH route development, and the truck lane initiation. However, majority of agricultural products traded through the borders are transported using the rural roads, from growing area to the factory, before continuing to the borders using different highways. It is, therefore, necessary for the Department of Rural Roads (DRR to plan for rural road improvement to accommodate the growth of the cross-border trades in the near future. This research, thus, aims to select potential rural roads to support cross-border shipment utilizing the analytic hierarchy process (AHP method. Seven key factors affecting rural roads selection, with references from transport and other related literatures, are extracted. They include:1 cross-border trade value, 2 distance from border to rural road, 3 agriculture and processed agriculture goods transported across the border, 4 compatibility with national strategies, 5 area characteristics around the rural road, 6 truck volume, and 7 number of rural roads in the radius of 50 kilometers from the border. Interviews are conducted with the experts based on seven key factors to collect data for the AHP analysis. The results identify the weight of each factor with an acceptable consistency ratio. It shows that the cross-border trade value is the most important factor as it achieves the highest weight. The distance from border to rural road and the compatibility with national strategies are also found crucial when making rural road selection decision. The Department of Rural Roads could use the results to select suitable roads, and plan for road improvement to support the crossborder shipment when the AEC is fully implemented.

  15. Application of a performance management framework for priced lanes.

    Science.gov (United States)

    2013-04-01

    The Texas Department of Transportation and its agency partners have implemented various forms of lane : management and pricing over the past three decades, including high-occupancy vehicle (HOV) lanes, highoccupancy toll lanes, managed lanes, and tol...

  16. An epidemiological survey on road traffic crashes in Iran: application of the two logistic regression models.

    Science.gov (United States)

    Bakhtiyari, Mahmood; Mehmandar, Mohammad Reza; Mirbagheri, Babak; Hariri, Gholam Reza; Delpisheh, Ali; Soori, Hamid

    2014-01-01

    Risk factors of human-related traffic crashes are the most important and preventable challenges for community health due to their noteworthy burden in developing countries in particular. The present study aims to investigate the role of human risk factors of road traffic crashes in Iran. Through a cross-sectional study using the COM 114 data collection forms, the police records of almost 600,000 crashes occurred in 2010 are investigated. The binary logistic regression and proportional odds regression models are used. The odds ratio for each risk factor is calculated. These models are adjusted for known confounding factors including age, sex and driving time. The traffic crash reports of 537,688 men (90.8%) and 54,480 women (9.2%) are analysed. The mean age is 34.1 ± 14 years. Not maintaining eyes on the road (53.7%) and losing control of the vehicle (21.4%) are the main causes of drivers' deaths in traffic crashes within cities. Not maintaining eyes on the road is also the most frequent human risk factor for road traffic crashes out of cities. Sudden lane excursion (OR = 9.9, 95% CI: 8.2-11.9) and seat belt non-compliance (OR = 8.7, CI: 6.7-10.1), exceeding authorised speed (OR = 17.9, CI: 12.7-25.1) and exceeding safe speed (OR = 9.7, CI: 7.2-13.2) are the most significant human risk factors for traffic crashes in Iran. The high mortality rate of 39 people for every 100,000 population emphasises on the importance of traffic crashes in Iran. Considering the important role of human risk factors in traffic crashes, struggling efforts are required to control dangerous driving behaviours such as exceeding speed, illegal overtaking and not maintaining eyes on the road.

  17. The improved degree of urban road traffic network: A case study of Xiamen, China

    Science.gov (United States)

    Wang, Shiguang; Zheng, Lili; Yu, Dexin

    2017-03-01

    The complex network theory is applied to the study of urban road traffic network topology, and we constructed a new measure to characterize an urban road network. It is inspiring to quantify the interaction more appropriately between nodes in complex networks, especially in the field of traffic. The measure takes into account properties of lanes (e.g. number of lanes, width, traffic direction). As much, it is a more comprehensive measure in comparison to previous network measures. It can be used to grasp the features of urban street network more clearly. We applied this measure to the road network in Xiamen, China. Based on a standard method from statistical physics, we examined in more detail the distribution of this new measure and found that (1) due to the limitation of space geographic attributes, traditional research conclusions acquired by using the original definition of degree to study the primal approach modeled urban street network are not very persuasive; (2) both of the direction of the network connection and the degree's odd or even classifications need to be analyzed specifically; (3) the improved degree distribution presents obvious hierarchy, and hierarchical values conform to the power-law distribution, and correlation of our new measure shows some significant segmentation of the urban road network.

  18. Understanding Traveler Behavior : The Psychology Behind Managed Lane Use

    Science.gov (United States)

    2012-07-01

    Recent analysis of Katy Freeway/Managed Lane (ML) travelers and I-394 Freeway/High : Occupancy Toll (HOT) lane traveler data has found that many travelers pay to use these HOT : lanes and MLs when adjacent toll-free lanes are operating at nearly the ...

  19. road sector development and economic growth in ethiopia1

    African Journals Online (AJOL)

    Eyerusalem

    Regarding community roads, both the management and accountancy .... previous years and its impact on overall and sectoral economic growth. Descriptive analysis is deployed to capture the link between the road transport sector and performance indicators, like rural accessibility, road density, road network, road financing ...

  20. An electric vehicle driving behavior model in the traffic system with a wireless charging lane

    Science.gov (United States)

    He, Jia; Huang, Hai-Jun; Yang, Hai; Tang, Tie-Qiao

    2017-09-01

    In this paper, a car-following model is proposed to study each EV's (electric vehicle) motion behavior near the WCL (wireless charging lane) and a lane-changing rule is designed to describe the EV's lane-changing behavior. Then, the car-following model and lane-changing rule are used to explore each EV's micro driving behavior in a two-lane system with a WCL. Finally, the impacts of the WCL on each EV's motion behavior are investigated. The numerical results show that each EV should run slowly on the WCL if it needs charge of electricity, that the EV's lane-changing behavior has great effects on the whole system, that the delay time caused by the WCL turns more prominent when the traffic turns heavy, and that lane-changing frequently occurs near the WCL (especially at the downstream of the WCL).

  1. Towards a definition of safety for individual drivers lane behavior

    NARCIS (Netherlands)

    van Loon, R.J.

    2012-01-01

    To assess lateral control performance in drivers, lane behaviour indicators such as the mean lane position, standard deviation of lane position and time-to-line-crossing are the most frequently used measures. For lane position, the commonly accepted (qualitative) proposition is that increased lane

  2. Advanced laser-based tracking device for motor vehicle lane position monitoring and steering assistance

    Science.gov (United States)

    Bachalo, William D.; Inenaga, Andrew; Schuler, Carlos A.

    1995-12-01

    Aerometrics is developing an innovative laser-diode based device that provides a warning signal when a motor-vehicle deviates from the center of the lane. The device is based on a sensor that scans the roadway on either side of the vehicle and determines the lateral position relative to the existing painted lines marking the lane. No additional markings are required. A warning is used to alert the driver of excessive weaving or unanticipated departure from the center of the lane. The laser beams are at invisible wavelengths to that operation of the device does not pose a distraction to the driver or other motorists: When appropriate markers are not present on the road, the device is capable of detecting this condition and warn the driver. The sensor system is expected to work well irrespective of ambient light levels, fog and rain. This sensor has enormous commercial potential. It could be marketed as an instrument to warn drivers that they are weaving, used as a research tool to monitor driving patterns, be required equipment for those previously convicted of driving under the influence, or used as a backup sensor for vehicle lateral position control. It can also be used in storage plants to guide robotic delivery vehicles. In this paper, the principles of operation of the sensor, and the results of Aerometrics ongoing testing will be presented.

  3. Changing lanes in a simulator: effects of aging on the control of the vehicle and visual inspection of mirrors and blind spot.

    Science.gov (United States)

    Lavalliere, Martin; Laurendeau, Denis; Simoneau, Martin; Teasdale, Normand

    2011-04-01

    The aim of this study was to examine lane change strategies in active younger and older drivers. Visual inspection of mirrors and the blind spot and the control of the vehicle were documented in a simulator environment. Younger (n = 10, 21-31 years) and older (n = 11, 65-75 years) active drivers drove through a continuous simulated environment including urban and rural sections. The scenario included events where, to negotiate a secure lane change, the driver needed to look at 3 regions of interest (ROI): (1) the rearview mirror, (2) the left side mirror, and (3) the left blind spot. The lane change maneuvers were necessary to avoid a vehicle parked halfway in the rightmost lane that was partially or completely blocking the lane or for overtaking a slower moving vehicle. Compared with younger drivers, older drivers showed a reduced frequency of visual inspection toward the rearview mirror and the blind spot. Also, though the older drivers showed a constant frequency of visual inspection across the 2 types of driving maneuvers, the younger drivers increased their frequency of inspection when overtaking a slower vehicle. Control of the car was mostly similar for both groups. A better knowledge of the drivers' visual search strategies when changing lanes could help in identifying suboptimal strategies at-risk of causing crashes and also serves to develop retraining programs.

  4. Intelligent driving in traffic systems with partial lane discipline

    Science.gov (United States)

    Assadi, Hamid; Emmerich, Heike

    2013-04-01

    It is a most common notion in traffic theory that driving in lanes and keeping lane changes to a minimum leads to smooth and laminar traffic flow, and hence to increased traffic capacity. On the other hand, there exist persistent vehicular traffic systems that are characterised by habitual disregarding of lane markings, and partial or complete loss of laminar traffic flow. Here, we explore the stability of such systems through a microscopic traffic flow model, where the degree of lane-discipline is taken as a variable, represented by the fraction of drivers that disregard lane markings completely. The results show that lane-free traffic may win over completely ordered traffic at high densities, and that partially ordered traffic leads to the poorest overall flow, while not considering the crash probability. Partial order in a lane-free system is similar to partial disorder in a lane-disciplined system in that both lead to decreased traffic capacity. This could explain the reason why standard enforcement methods, which rely on continuous increase of order, often fail to incur order to lane-free traffic systems. The results also provide an insight into the cooperative phenomena in open systems with self-driven particles.

  5. Life in the Fast Lane: Road Crossing Behavior of Mule Deer in a Wildland-Urban Interface

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, Leslie A. [Los Alamos National Laboratory; Biggs, James [Northern New Mexico College; Bennett, Kathryn D. [Los Alamos National Laboratory; Bare, Carey [Bare and Associates, LLC; Sherwood, Sherri R. [Los Alamos National Laboratory

    2012-04-04

    In 2009, approximately 260,000 animal-vehicle collisions were reported in the United States, resulting in 12,000 human injuries and 173 human fatalities. Research has focused on identifying factors associated with high densities of animal-vehicle collisions, including variables such as traffic speed and volume, road design, topographic features, vegetative cover, and local deer or elk (Cervus elaphus) abundance. The purposes of this study were to document how often and where mule deer (Odocoileus hemionus) crossed roads in a western United States wildland-urban interface area, and to relate deer road-crossing behavior to deer-vehicle collision locations. Seven adult mule deer (four males [M] and three females [F]) were captured and collared with GPS-enabled collars during December 2001 and January 2002. Five of the seven deployed collars were recovered. None of the roads in the study area appeared to act as a substantial barrier to deer passage. Deer home ranges straddled highways and primary, secondary, and tertiary arterial roads. Deer crossed all types of roads. The average number of times deer crossed road during 24 hours of monitoring ranged from 2.1 to 7.0. Deer in the Los Alamos townsite avoided crossing roads during day and before sunset. Deer-vehicle accidents occurred at 350 percent of the level expected after sunset. All other time periods had fewer accidents than expected. The distribution of accidents across time periods was not similar to the distribution of road crossings across time periods for any deer. Within Los Alamos County there was a clear trend for deer-vehicle collisions to occur on roads with speed limits > 35 mph. Deer in the townsite frequently crossed roads with lower speed limits; therefore, the reason for the paucity of accidents along these roads was evidently the ability of drivers to detect deer (or the ability of deer to detect vehicles) and respond before an accident occurred. There was a significant but not strong correlation

  6. Diurnal variation of on-road air pollution in an urban street canyon in Seoul

    Science.gov (United States)

    Ho, Woo, Sung; Lee, Seung-Bok; Kim, Kyung Hwan; Bae, Gwi-Nam; Sunwoo, Young; Ma, Young-Il; Han, Dokyoung; Song, Sanghoo

    2014-05-01

    Motor vehicles are a major source of CO, NOx and particulate matters. Especially, in the surroundings of high-raised buildings, so-called an urban street canyon, air pollution levels increase due to limited dispersion of vehicle emissions. In this study, a mobile laboratory was used to measure diurnal variation of on-road concentrations of air pollutants such as NOx, particle-bound polycyclic aromatic hydrocarbons, black carbon and particle number in the urban street canyon on the Teheran road with eight lanes in Seoul, Korea from 5th to 8th November 2013. Each traveling distance was about 3.3km. Traveling vehicle at the middle of the Teheran road was recorded by video camera, and then the car counting by vehicle types. On road measurements conducted for 3~6 hours per day. Hourly average of air pollutant concentration in morning rush hour more than two times higher than those at the daybreak. We will analyze the correlation between air pollution levels and traffic volume by vehicle types. We will discuss about spatial characteristics of on-road air pollution levels in the urban street canyon.

  7. Environmental resources and poverty in rural communities

    DEFF Research Database (Denmark)

    Charlery, Lindy Callen

    , is to be sustainably realized. However, most datasets on rural livelihoods do not accurately account for environmental income and therefore cannot answer this question. The Poverty Environment Network (PEN) project was initiated specifically to address this issue in the assessment of rural livelihoods in developing......D study focuses on answering two main research questions: 1) What is the importance of environmental income in assessments of poverty and poverty dynamics in rural forest reliant communities? and 2) What are the impacts of infrastructural development, in the form of rural roads, on rural household income......Over the last two decades, the burgeoning empirical evidence on the importance of forests and environmental resources to rural livelihoods in developing countries has attracted the attention of policy makers aiming to develop and implement strategies for reducing poverty and improving livelihoods...

  8. Head-on crashes on two-way interurban roads: a public health concern in road safety.

    Science.gov (United States)

    Olabarria, Marta; Santamariña-Rubio, Elena; Marí-Dell'Olmo, Marc; Gotsens, Mercè; Novoa, Ana M; Borrell, Carme; Pérez, Katherine

    2015-09-01

    To describe the magnitude and characteristics of crashes and drivers involved in head-on crashes on two-way interurban roads in Spain between 2007 and 2012, and to identify the factors associated with the likelihood of head-on crashes on these roads compared with other types of crash. A cross-sectional study was conducted using the National Crash Register. The dependent variables were head-on crashes with injury (yes/no) and drivers involved in head-on crashes (yes/no). Factors associated with head-on crashes and with being a driver involved in a head-on crash versus other types of crash were studied using a multivariate robust Poisson regression model to estimate proportion ratios (PR) and confidence intervals (95% CI). There were 9,192 head-on crashes on two-way Spanish interurban roads. A total of 15,412 men and 3,862 women drivers were involved. Compared with other types of crash, head-on collisions were more likely on roads 7 m or more wide, on road sections with curves, narrowings or drop changes, on wet or snowy surfaces, and in twilight conditions. Transgressions committed by drivers involved in head-on crashes were driving in the opposite direction and incorrectly overtaking another vehicle. Factors associated with a lower probability of head-on crashes were the existence of medians (PR=0.57; 95%CI: 0.48-0.68) and a paved shoulder of less than 1.5 meters (PR=0.81; 95%CI: 0.77-0.86) or from 1.5 to 2.45 meters (PR=0.90; 95%CI: 0.84-0.96). This study allowed the characterization of crashes and drivers involved in head-on crashes on two-way interurban roads. The lower probability observed on roads with median strips point to these measures as an effective way to reduce these collisions. Copyright © 2014 SESPAS. Published by Elsevier Espana. All rights reserved.

  9. Road pricing, air pollution and external costs; Road pricing, luftforurening og eksternalitetsomkostninger

    Energy Technology Data Exchange (ETDEWEB)

    Solvang Jensen, S.; Ketzel, M. (Aarhus Univ., Danmarks Miljoeundersoegelser, Afd. for Atmosfaerisk Miljoe, Roskilde (Denmark)); Skou Andersen, M. (Aarhus Univ., Danmarks Miljoeundersoegelser, Afd. for Systemanalyse, Roskilde (Denmark))

    2010-06-15

    The objective of this assessment is to improve the foundation for decision-making about introduction of a road pricing system that aims to reduce the health impacts and social costs of traffic-related air pollution. The analysis focuses on how road emissions, air quality, population exposure, and social costs of air pollution depend on geography (different city sizes and rural areas) and time of the day (rush hours versus non-rush hours). A review of Danish studies related to road pricing has also been carried out to assess the expected effect of road pricing on traffic performance (km travelled), vehicle composition and speed that are factors affecting air pollution. (LN)

  10. How long do the dead survive on the road? Carcass persistence probability and implications for road-kill monitoring surveys.

    Directory of Open Access Journals (Sweden)

    Sara M Santos

    Full Text Available BACKGROUND: Road mortality is probably the best-known and visible impact of roads upon wildlife. Although several factors influence road-kill counts, carcass persistence time is considered the most important determinant underlying underestimates of road mortality. The present study aims to describe and model carcass persistence variability on the road for different taxonomic groups under different environmental conditions throughout the year; and also to assess the effect of sampling frequency on the relative variation in road-kill estimates registered within a survey. METHODOLOGY/PRINCIPAL FINDINGS: Daily surveys of road-killed vertebrates were conducted over one year along four road sections with different traffic volumes. Survival analysis was then used to i describe carcass persistence timings for overall and for specific animal groups; ii assess optimal sampling designs according to research objectives; and iii model the influence of road, animal and weather factors on carcass persistence probabilities. Most animal carcasses persisted on the road for the first day only, with some groups disappearing at very high rates. The advisable periodicity of road monitoring that minimizes bias in road mortality estimates is daily monitoring for bats (in the morning and lizards (in the afternoon, daily monitoring for toads, small birds, small mammals, snakes, salamanders, and lagomorphs; 1 day-interval (alternate days for large birds, birds of prey, hedgehogs, and freshwater turtles; and 2 day-interval for carnivores. Multiple factors influenced the persistence probabilities of vertebrate carcasses on the road. Overall, the persistence was much lower for small animals, on roads with lower traffic volumes, for carcasses located on road lanes, and during humid conditions and high temperatures during the wet season and dry seasons, respectively. CONCLUSION/SIGNIFICANCE: The guidance given here on monitoring frequencies is particularly relevant to provide

  11. How long do the dead survive on the road? Carcass persistence probability and implications for road-kill monitoring surveys.

    Science.gov (United States)

    Santos, Sara M; Carvalho, Filipe; Mira, António

    2011-01-01

    Road mortality is probably the best-known and visible impact of roads upon wildlife. Although several factors influence road-kill counts, carcass persistence time is considered the most important determinant underlying underestimates of road mortality. The present study aims to describe and model carcass persistence variability on the road for different taxonomic groups under different environmental conditions throughout the year; and also to assess the effect of sampling frequency on the relative variation in road-kill estimates registered within a survey. Daily surveys of road-killed vertebrates were conducted over one year along four road sections with different traffic volumes. Survival analysis was then used to i) describe carcass persistence timings for overall and for specific animal groups; ii) assess optimal sampling designs according to research objectives; and iii) model the influence of road, animal and weather factors on carcass persistence probabilities. Most animal carcasses persisted on the road for the first day only, with some groups disappearing at very high rates. The advisable periodicity of road monitoring that minimizes bias in road mortality estimates is daily monitoring for bats (in the morning) and lizards (in the afternoon), daily monitoring for toads, small birds, small mammals, snakes, salamanders, and lagomorphs; 1 day-interval (alternate days) for large birds, birds of prey, hedgehogs, and freshwater turtles; and 2 day-interval for carnivores. Multiple factors influenced the persistence probabilities of vertebrate carcasses on the road. Overall, the persistence was much lower for small animals, on roads with lower traffic volumes, for carcasses located on road lanes, and during humid conditions and high temperatures during the wet season and dry seasons, respectively. The guidance given here on monitoring frequencies is particularly relevant to provide conservation and transportation agencies with accurate numbers of road

  12. Glaucoma and Driving: On-Road Driving Characteristics

    Science.gov (United States)

    Wood, Joanne M.; Black, Alex A.; Mallon, Kerry; Thomas, Ravi; Owsley, Cynthia

    2016-01-01

    Purpose To comprehensively investigate the types of driving errors and locations that are most problematic for older drivers with glaucoma compared to those without glaucoma using a standardized on-road assessment. Methods Participants included 75 drivers with glaucoma (mean = 73.2±6.0 years) with mild to moderate field loss (better-eye MD = -1.21 dB; worse-eye MD = -7.75 dB) and 70 age-matched controls without glaucoma (mean = 72.6 ± 5.0 years). On-road driving performance was assessed in a dual-brake vehicle by an occupational therapist using a standardized scoring system which assessed the types of driving errors and the locations where they were made and the number of critical errors that required an instructor intervention. Driving safety was rated on a 10-point scale. Self-reported driving ability and difficulties were recorded using the Driving Habits Questionnaire. Results Drivers with glaucoma were rated as significantly less safe, made more driving errors, and had almost double the rate of critical errors than those without glaucoma. Driving errors involved lane positioning and planning/approach, and were significantly more likely to occur at traffic lights and yield/give-way intersections. There were few between group differences in self-reported driving ability. Conclusions Older drivers with glaucoma with even mild to moderate field loss exhibit impairments in driving ability, particularly during complex driving situations that involve tactical problems with lane-position, planning ahead and observation. These results, together with the fact that these drivers self-report their driving to be relatively good, reinforce the need for evidence-based on-road assessments for evaluating driving fitness. PMID:27472221

  13. Glaucoma and Driving: On-Road Driving Characteristics.

    Directory of Open Access Journals (Sweden)

    Joanne M Wood

    Full Text Available To comprehensively investigate the types of driving errors and locations that are most problematic for older drivers with glaucoma compared to those without glaucoma using a standardized on-road assessment.Participants included 75 drivers with glaucoma (mean = 73.2±6.0 years with mild to moderate field loss (better-eye MD = -1.21 dB; worse-eye MD = -7.75 dB and 70 age-matched controls without glaucoma (mean = 72.6 ± 5.0 years. On-road driving performance was assessed in a dual-brake vehicle by an occupational therapist using a standardized scoring system which assessed the types of driving errors and the locations where they were made and the number of critical errors that required an instructor intervention. Driving safety was rated on a 10-point scale. Self-reported driving ability and difficulties were recorded using the Driving Habits Questionnaire.Drivers with glaucoma were rated as significantly less safe, made more driving errors, and had almost double the rate of critical errors than those without glaucoma. Driving errors involved lane positioning and planning/approach, and were significantly more likely to occur at traffic lights and yield/give-way intersections. There were few between group differences in self-reported driving ability.Older drivers with glaucoma with even mild to moderate field loss exhibit impairments in driving ability, particularly during complex driving situations that involve tactical problems with lane-position, planning ahead and observation. These results, together with the fact that these drivers self-report their driving to be relatively good, reinforce the need for evidence-based on-road assessments for evaluating driving fitness.

  14. Glaucoma and Driving: On-Road Driving Characteristics.

    Science.gov (United States)

    Wood, Joanne M; Black, Alex A; Mallon, Kerry; Thomas, Ravi; Owsley, Cynthia

    2016-01-01

    To comprehensively investigate the types of driving errors and locations that are most problematic for older drivers with glaucoma compared to those without glaucoma using a standardized on-road assessment. Participants included 75 drivers with glaucoma (mean = 73.2±6.0 years) with mild to moderate field loss (better-eye MD = -1.21 dB; worse-eye MD = -7.75 dB) and 70 age-matched controls without glaucoma (mean = 72.6 ± 5.0 years). On-road driving performance was assessed in a dual-brake vehicle by an occupational therapist using a standardized scoring system which assessed the types of driving errors and the locations where they were made and the number of critical errors that required an instructor intervention. Driving safety was rated on a 10-point scale. Self-reported driving ability and difficulties were recorded using the Driving Habits Questionnaire. Drivers with glaucoma were rated as significantly less safe, made more driving errors, and had almost double the rate of critical errors than those without glaucoma. Driving errors involved lane positioning and planning/approach, and were significantly more likely to occur at traffic lights and yield/give-way intersections. There were few between group differences in self-reported driving ability. Older drivers with glaucoma with even mild to moderate field loss exhibit impairments in driving ability, particularly during complex driving situations that involve tactical problems with lane-position, planning ahead and observation. These results, together with the fact that these drivers self-report their driving to be relatively good, reinforce the need for evidence-based on-road assessments for evaluating driving fitness.

  15. SOCIO-SPATIAL INTEGRATION OF LANDSCAPE BACK LANE OF HOUSING AT BANDAR BARU NILAI: PRIVACY AND COMMUNITY

    Directory of Open Access Journals (Sweden)

    SITI F. M. LIAS

    2016-05-01

    Full Text Available Urban informal spaces in the form of back lane tend to promote socio-spatial integration between neighbourhood communities. The Back Lane Planning Design Guidelines issued in 2014 by Town and Country Planning Department of Malaysia identified back lane as such a place to encourage communal lifestyle whereas an area of owns residents privacy. In reality, back lane portrays as the wasted unfavourable paths thus several social concerns of safety, security, health issues as well as invading privacy and sense of deficiency community bonding issues arise. This study quantitatively analyses dwellers perception focusing to level of visual privacy and level of spiritual neighbourhood interaction towards effectiveness of newly landscape back lane (LBL in contemporary urban dwellings. Comparison of socio-spatial integration between two types of back lane design in grid-linear housing scheme ; the pleasing greenery landscape back lane (LBL and the plain empty bare paved back lane (PBL in residential area of Kota Seriemas, Nilai, Negeri Sembilan . Structured questionnaire distributed to 115 respondents to assess on privacy and comfort level, neighbourhood activities and communal lifestyle, back -lane usage, resident’s perception and expectation.The study proved the landscape design back lane (LBL is ensuring own right privacy lacking in promoting community interaction among the residents due to contemporary urban lifestyles.

  16. The influence of road curvature on fatal crashes in New Zealand

    DEFF Research Database (Denmark)

    Haynes, Robin; Lake, Iain R.; Kingham, Simon

    2008-01-01

    Bends in roads can cause crashes but a recent study in the UK found that areas with mostly curved roads had lower crash rates than areas with straighter roads. This present study aimed to replicate the previous research in a different country. Variations in the number of fatal road crashes...... occurring between 1996 and 2005 in 73 territorial local authorities across New Zealand were modelled against possible predictors. The predictors were traffic flow, population counts and characteristics, car use, socio-economic deprivation, climate, altitude and road characteristics including four measures...... of average road curvature. The best predictors of the number of fatal crashes on urban roads, rural state highways and other rural roads were traffic flow, speed limitation and socio-economic deprivation. Holding significant factors constant, there was no evidence that TLAs with the most curved roads had...

  17. Lane-changing model with dynamic consideration of driver's propensity

    Science.gov (United States)

    Wang, Xiaoyuan; Wang, Jianqiang; Zhang, Jinglei; Ban, Xuegang Jeff

    2015-07-01

    Lane-changing is the driver's selection result of the satisfaction degree in different lane driving conditions. There are many different factors influencing lane-changing behavior, such as diversity, randomicity and difficulty of measurement. So it is hard to accurately reflect the uncertainty of drivers' lane-changing behavior. As a result, the research of lane-changing models is behind that of car-following models. Driver's propensity is her/his emotion state or the corresponding preference of a decision or action toward the real objective traffic situations under the influence of various dynamic factors. It represents the psychological characteristics of the driver in the process of vehicle operation and movement. It is an important factor to influence lane-changing. In this paper, dynamic recognition of driver's propensity is considered during simulation based on its time-varying discipline and the analysis of the driver's psycho-physic characteristics. The Analytic Hierarchy Process (AHP) method is used to quantify the hierarchy of driver's dynamic lane-changing decision-making process, especially the influence of the propensity. The model is validated using real data. Test results show that the developed lane-changing model with the dynamic consideration of a driver's time-varying propensity and the AHP method are feasible and with improved accuracy.

  18. Detection and analyse of hazardous roads in rural areas

    DEFF Research Database (Denmark)

    Sørensen, Michael

    2003-01-01

    For the last period of 5-10 years the notion "Grey roads" (hazardous roads) has appeared in Danish traffic safety work and improvement of these roads has become a very important part of the traffic safety work in many countries. The problem is, that the notion never has been clearly defined......, and therefore there are no unambiguos methods to point out and analyse "Grey roads". In this article based on a ph.D.-project a method to detecting "Grey roads" is introduced....

  19. Investigation of the impact of low cost traffic engineering measures on road safety in urban areas.

    Science.gov (United States)

    Yannis, George; Kondyli, Alexandra; Georgopoulou, Xenia

    2014-01-01

    This paper investigates the impact of low cost traffic engineering measures (LCTEMs) on the improvement of road safety in urban areas. A number of such measures were considered, such as speed humps, woonerfs, raised intersections and other traffic calming measures, which have been implemented on one-way, one-lane roads in the Municipality of Neo Psychiko in the Greater Athens Area. Data were analysed using the before-and-after safety analysis methodology with large control group. The selected control group comprised of two Municipalities in the Athens Greater Area, which present similar road network and land use characteristics with the area considered. The application of the methodology showed that the total number of crashes presented a statistically significant reduction, which can be possibly attributed to the introduction of LCTEMs. This reduction concerns passenger cars and single-vehicle crashes and is possibly due to the behavioural improvement of drivers of 25 years old or more. The results of this research are very useful for the identification of the appropriate low cost traffic engineering countermeasures for road safety problems in urban areas.

  20. Assessment of the neighborhood environmental effects of highway improvements through micronetwork simulation

    Energy Technology Data Exchange (ETDEWEB)

    Schimpeler, C.C. (Schimpeler--Corradino Associates, Louisville, KY); Corradino, J.C.; Siria, B.S.

    1978-01-01

    New Cut Road is a major arterial highway serving South Louisville. Until recently, it was a narrow two-lane highway of rural-type design carrying up to 14,000 vehicles per day under forced flow conditions. Then construction began to widen the road from Southside Drive to Old Third Street Road, as a result of Urban Corridor Demonstration Program funding. The impacts (traffic, noise, and air pollution) on the neighborhoods surrounding this widening have been measured through micronetwork simulation techniques. Traffic will be diverted from surrounding roads (up to 20 percent) to the widened New Cut facility, thereby eliminating ''over-capacity'' conditions in these facilities, adding several years' life. Further, expeditious movement of vehicles through the New Cut Road ''area of influence'' will have a beneficial, albeit small, effect on the local air and noise environment. New Cut Road will be a highly cost-effective, low-capital-intensive improvement.

  1. Prediction of Driver's Intention of Lane Change by Augmenting Sensor Information Using Machine Learning Techniques.

    Science.gov (United States)

    Kim, Il-Hwan; Bong, Jae-Hwan; Park, Jooyoung; Park, Shinsuk

    2017-06-10

    Driver assistance systems have become a major safety feature of modern passenger vehicles. The advanced driver assistance system (ADAS) is one of the active safety systems to improve the vehicle control performance and, thus, the safety of the driver and the passengers. To use the ADAS for lane change control, rapid and correct detection of the driver's intention is essential. This study proposes a novel preprocessing algorithm for the ADAS to improve the accuracy in classifying the driver's intention for lane change by augmenting basic measurements from conventional on-board sensors. The information on the vehicle states and the road surface condition is augmented by using an artificial neural network (ANN) models, and the augmented information is fed to a support vector machine (SVM) to detect the driver's intention with high accuracy. The feasibility of the developed algorithm was tested through driving simulator experiments. The results show that the classification accuracy for the driver's intention can be improved by providing an SVM model with sufficient driving information augmented by using ANN models of vehicle dynamics.

  2. Appropriate roads for rural access

    CSIR Research Space (South Africa)

    Paige-Green, P

    2006-03-01

    Full Text Available be reduced, the result remains environmentally unsustainable. Low cost but appropriate techniques for upgrading these roads cost-effectively to sealed standards have been implemented in many countries recently. These techniques optimize the use of local...

  3. The Effect of Sharrows, Painted Bicycle Lanes and Physically Protected Paths on the Severity of Bicycle Injuries Caused by Motor Vehicles.

    Science.gov (United States)

    Wall, Stephen P; Lee, David C; Frangos, Spiros G; Sethi, Monica; Heyer, Jessica H; Ayoung-Chee, Patricia; DiMaggio, Charles J

    2016-01-01

    We conducted individual and ecologic analyses of prospectively collected data from 839 injured bicyclists who collided with motorized vehicles and presented to Bellevue Hospital, an urban Level-1 trauma center in New York City, from December 2008 to August 2014. Variables included demographics, scene information, rider behaviors, bicycle route availability, and whether the collision occurred before the road segment was converted to a bicycle route. We used negative binomial modeling to assess the risk of injury occurrence following bicycle path or lane implementation. We dichotomized U.S. National Trauma Data Bank Injury Severity Scores (ISS) into none/mild (0-8) versus moderate, severe, or critical (>8) and used adjusted multivariable logistic regression to model the association of ISS with collision proximity to sharrows (i.e., bicycle lanes designated for sharing with cars), painted bicycle lanes, or physically protected paths. Negative binomial modeling of monthly counts, while adjusting for pedestrian activity, revealed that physically protected paths were associated with 23% fewer injuries. Painted bicycle lanes reduced injury risk by nearly 90% (IDR 0.09, 95% CI 0.02-0.33). Holding all else equal, compared to no bicycle route, a bicycle injury nearby sharrows was nearly twice as likely to be moderate, severe, or critical (adjusted odds ratio 1.94; 95% confidence interval (CI) 0.91-4.15). Painted bicycle lanes and physically protected paths were 1.52 (95% CI 0.85-2.71) and 1.66 (95% CI 0.85-3.22) times as likely to be associated with more than mild injury respectively.

  4. The Effect of Sharrows, Painted Bicycle Lanes and Physically Protected Paths on the Severity of Bicycle Injuries Caused by Motor Vehicles

    Directory of Open Access Journals (Sweden)

    Stephen P. Wall

    2016-12-01

    Full Text Available We conducted individual and ecologic analyses of prospectively collected data from 839 injured bicyclists who collided with motorized vehicles and presented to Bellevue Hospital, an urban Level-1 trauma center in New York City, from December 2008 to August 2014. Variables included demographics, scene information, rider behaviors, bicycle route availability, and whether the collision occurred before the road segment was converted to a bicycle route. We used negative binomial modeling to assess the risk of injury occurrence following bicycle path or lane implementation. We dichotomized U.S. National Trauma Data Bank Injury Severity Scores (ISS into none/mild (0–8 versus moderate, severe, or critical (>8 and used adjusted multivariable logistic regression to model the association of ISS with collision proximity to sharrows (i.e., bicycle lanes designated for sharing with cars, painted bicycle lanes, or physically protected paths. Negative binomial modeling of monthly counts, while adjusting for pedestrian activity, revealed that physically protected paths were associated with 23% fewer injuries. Painted bicycle lanes reduced injury risk by nearly 90% (IDR 0.09, 95% CI 0.02–0.33. Holding all else equal, compared to no bicycle route, a bicycle injury nearby sharrows was nearly twice as likely to be moderate, severe, or critical (adjusted odds ratio 1.94; 95% confidence interval (CI 0.91–4.15. Painted bicycle lanes and physically protected paths were 1.52 (95% CI 0.85–2.71 and 1.66 (95% CI 0.85–3.22 times as likely to be associated with more than mild injury respectively.

  5. Quantifying the number of lane changes in traffic : An empirical analysis

    NARCIS (Netherlands)

    Knoop, V.L.; Hoogendoorn, S.P.; Shiomi, Y.; Buisson, C.

    2012-01-01

    Lane changes are an important aspect of freeway flow. Most lane change models are microscopic, describing whether individual vehicles/drives will change lanes, and hence are calibrated microscopically. Macroscopic validation often is restricted to the distribution of vehicles across lanes. To the

  6. The Road Movies' Space Dynamics in the 70s: Richard C. Sarafian, Monte Hellman and Terrence Malick

    Directory of Open Access Journals (Sweden)

    Filipa Rosário

    2014-07-01

    Full Text Available Vanishing Point (Richard C. Sarafian, 1971, Two-lane Blacktop (Monte Hellmann, 1971 and Badlands (Terrence Malick, 1973 are road movies that incorporate distinctive journeys, which, at a certain moment, become similar. Their heroes act as non-mystical pilgrims to whom the trip is a journey in itself, even if they come up as a chase, a car race or an escape from the police.In a filmic genre built from the spatial element, the road life structures each narrative in each film. In this way, the moment when the journey looses its teleological sense acquires even more relevance, allowing us to understand the genre’s space dynamics with a different depth.In this essay, I will analyse comparatively the ways through which characters and directors relate to the scenery/landscape, in order to identify ideological constraints related to space, i.e., those symbolic limitations the road movie seems to conceal. Easy Rider (Dennis Hopper, 1969 will be a constant presence since, as the inaugural road movie, it has determined the genre’s underlying forces.

  7. Lane Determination with GPS Precise Point Positioning

    NARCIS (Netherlands)

    Knoop, V.L.; de Bakker, P.F.; Tiberius, C.C.J.M.; van Arem, B.

    2017-01-01

    Modern intelligent transport solutions can achieve an improvement of traffic flow on motorways. With lane-specific measurements and lane-specific control, more measures are possible. Single frequency precise point positioning (PPP) is a newly developed and affordable technique to achieve an

  8. Development of a sensor platform for roadway mapping : part b - mapping the road fog lines : final report.

    Science.gov (United States)

    2015-04-01

    Our objective is the development and evaluation of a low-cost, vehicle-mounted sensor suite capable of generating : map data with lane and road boundary information accurate to the 10 cm (4 in) level. Such a map could be used for : a number of differ...

  9. Water-soluble ions in nano/ultrafine/fine/coarse particles collected near a busy road and at a rural site

    International Nuclear Information System (INIS)

    Lin, C.-C.; Chen, S.-J.; Huang, K.-L.; Lee, W.-J.; Lin, W.-Y.; Liao, C.-J.; Chaung, H.-C.; Chiu, C.-H.

    2007-01-01

    This study investigated water-soluble ions in the sized particles (particularly nano (PM 0.01-0.056 )/ultrafine (PM 0.01-0.1 )) collected using MOUDI and Nano-MOUDI samplers near a busy road site and at a rural site. The analytical results demonstrate that nano and coarse particles exhibited the highest (16.3%) and lowest (8.37%) nitrate mass ratios, respectively. The mass ratio of NO 3 - was higher than that of SO 4 2- in all the sized particles at the traffic site. The secondary aerosols all displayed trimodal distributions. The aerosols in ultrafine particles collected at the roadside site exhibited Aitken mode distributions indicating they were of local origin. This finding was not observed for those ultrafine particles collected at the rural site. The mass median diameters (MMDs) of the nano, ultrafine, and fine particles were smaller at the traffic site than at the rural site, possibly related to the contribution of mobile engine emissions. - NO 3 - > SO 4 2- in mass ratio, different from common observations in rural areas, was found in (particularly the nano) traffic-associated particles

  10. Real-time 3D reconstruction of road curvature in far look-ahead distance from analysis of image sequences

    Science.gov (United States)

    Behringer, Reinhold

    1995-12-01

    A system for visual road recognition in far look-ahead distance, implemented in the autonomous road vehicle VaMP (a passenger car), is described. Visual cues of a road in a video image are the bright lane markings and the edges formed at the road borders. In a distance of more than 100 m, the most relevant road cue is the homogeneous road area, limited by the two border edges. These cues can be detected by the image processing module KRONOS applying edge detection techniques and areal 2D segmentation based on resolution triangles (analogous to a resolution pyramid). An estimation process performs an update of a state vector, which describes spatial road shape and vehicle orientation relative to the road. This state vector is estimated every 40 ms by exploiting knowledge about the vehicle movement (spatio-temporal model of vehicle dynamics) and the road design rules (clothoidal segments). Kalman filter techniques are applied to obtain an optimal estimate of the state vector by evaluating the measurements of the road border positions in the image sequence taken by a set of CCD cameras. The road consists of segments with piecewise constant curvature parameters. The borders between these segments can be detected by applying methods which have been developed for detection of discontinuities during time-discrete measurements. The road recognition system has been tested in autonomous rides with VaMP on public Autobahnen in real traffic at speeds up to 130 km/h.

  11. Prediction of Driver’s Intention of Lane Change by Augmenting Sensor Information Using Machine Learning Techniques

    Science.gov (United States)

    Kim, Il-Hwan; Bong, Jae-Hwan; Park, Jooyoung; Park, Shinsuk

    2017-01-01

    Driver assistance systems have become a major safety feature of modern passenger vehicles. The advanced driver assistance system (ADAS) is one of the active safety systems to improve the vehicle control performance and, thus, the safety of the driver and the passengers. To use the ADAS for lane change control, rapid and correct detection of the driver’s intention is essential. This study proposes a novel preprocessing algorithm for the ADAS to improve the accuracy in classifying the driver’s intention for lane change by augmenting basic measurements from conventional on-board sensors. The information on the vehicle states and the road surface condition is augmented by using an artificial neural network (ANN) models, and the augmented information is fed to a support vector machine (SVM) to detect the driver’s intention with high accuracy. The feasibility of the developed algorithm was tested through driving simulator experiments. The results show that the classification accuracy for the driver’s intention can be improved by providing an SVM model with sufficient driving information augmented by using ANN models of vehicle dynamics. PMID:28604582

  12. Prediction of Driver’s Intention of Lane Change by Augmenting Sensor Information Using Machine Learning Techniques

    Directory of Open Access Journals (Sweden)

    Il-Hwan Kim

    2017-06-01

    Full Text Available Driver assistance systems have become a major safety feature of modern passenger vehicles. The advanced driver assistance system (ADAS is one of the active safety systems to improve the vehicle control performance and, thus, the safety of the driver and the passengers. To use the ADAS for lane change control, rapid and correct detection of the driver’s intention is essential. This study proposes a novel preprocessing algorithm for the ADAS to improve the accuracy in classifying the driver’s intention for lane change by augmenting basic measurements from conventional on-board sensors. The information on the vehicle states and the road surface condition is augmented by using an artificial neural network (ANN models, and the augmented information is fed to a support vector machine (SVM to detect the driver’s intention with high accuracy. The feasibility of the developed algorithm was tested through driving simulator experiments. The results show that the classification accuracy for the driver’s intention can be improved by providing an SVM model with sufficient driving information augmented by using ANN models of vehicle dynamics.

  13. Road traffic injuries among riders of electric bike/electric moped in southern China.

    Science.gov (United States)

    Zhang, Xujun; Yang, Yaming; Yang, Jie; Hu, Jie; Li, Yang; Wu, Ming; Stallones, Lorann; Xiang, Henry

    2018-05-19

    Electric bike/moped-related road traffic injuries have become a burgeoning public health problem in China. The objective of this study was to identify the prevalence and potential risk factors of electric bike/moped-related road traffic injuries among electric bike/moped riders in southern China. A cross-sectional study was used to interview 3,151 electric bike/moped riders in southern China. Electric bike/moped-related road traffic injuries that occurred from July 2014 to June 2015 were investigated. Data were collected by face-to-face interviews and analyzed between July 2015 and June 2017. The prevalence of electric bike/moped-related road traffic injuries among the investigated riders was 15.99%. Electric bike/moped-related road traffic injuries were significantly associated with category of electric bike (adjusted odds ratio [AOR] = 1.36, 95% confidence interval [CI], 1.01-1.82), self-reported confusion (AOR = 1.77, 95% CI, 1.13-2.78), history of crashes (AOR = 6.14, 95% CI, 4.68-8.07), running red lights (AOR = 3.57, 95% CI, 2.42-5.25), carrying children while riding (AOR = 1.96, 95% CI, 1.37-2.85), carrying adults while riding (AOR = 1.68, 95% CI, 1.23-2.28), riding in the motor lane (AOR = 2.42, 95% CI, 1.05-3.93), and riding in the wrong traffic direction (AOR = 1.63, 95% CI, 1.13-2.35). In over 77.58% of electric bike/moped-related road traffic crashes, riders were determined by the police to be responsible for the crash. Major crash-causing factors included violating traffic signals or signs, careless riding, speeding, and riding in the wrong lane. Traffic safety related to electric bikes/moped is becoming more problematic with growing popularity compared with other 2-wheeled vehicles. Programs need to be developed to prevent electric bike/moped-related road traffic injuries in this emerging country.

  14. Express Lane Eligibility for Medicaid and CHIP Coverage

    Data.gov (United States)

    U.S. Department of Health & Human Services — States may rely on eligibility information from "Express Lane" agency programs to streamline and simplify enrollment and renewal in Medicaid and CHIP. Express Lane...

  15. Traffic flow behavior at a single-lane urban roundabout

    Science.gov (United States)

    Lakouari, N.; Oubram, O.; Ez-Zahraouy, H.; Cisneros-Villalobos, L.; Velásquez-Aguilar, J. G.

    In this paper, we propose a stochastic cellular automata model to study the traffic behavior at a single-lane roundabout. Vehicles can enter the interior lane or exit from it via N intersecting lane, the boundary conditions are stochastic. The traffic is controlled by a self-organized scheme. It has turned out that depending on the rules of insertion to the roundabout, five distinct traffic phases can appear, namely, free flow, congestion, maximum current, jammed and gridlock. The transition between the free flow and the gridlock is forbidden. The density profiles are used to study the traffic pattern at the interior lane of the roundabout. In order to quantify the interactions between vehicles in the interior lane of the roundabout, the velocity correlation coefficient (VCC) is also studied. Besides, the spatiotemporal diagrams corresponding to the entry/exit lanes are derived numerically. Furthermore, we have investigated the effect of displaying signal (PIn), as the PIn decreases, the maximum current increases at the expense of the free flow and the jamming phase. Finally, we have investigated the effect of the braking probability P on the interior lane of the roundabout. We have found that the increase of P raises the spontaneous jam formation on the ring. Thus, enlarges the maximum current and the jamming phase while the free flow phase decreases.

  16. Wildlife friendly roads: the impacts of roads on wildlife in urban areas and potential remedies

    Science.gov (United States)

    Riley, Seth P D; Brown, Justin L.; Sikich, Jeff A.; Schoonmaker, Catherine M.; Boydston, Erin E.

    2014-01-01

    Roads are one of the most important factors affecting the ability of wildlife to live and move within an urban area. Roads physically replace wildlife habitat and often reduce habitat quality nearby, fragment the remaining habitat, and cause increased mortality through vehicle collisions. Much ecological research on roads has focused on whether animals are successfully crossing roads, or if the road is a barrier to wildlife movement, gene flow, or functional connectivity. Roads can alter survival and reproduction for wildlife, even among species such as birds that cross roads easily. Here we examine the suite of potential impacts of roads on wildlife, but we focus particularly on urban settings. We report on studies, both in the literature and from our own experience, that have addressed wildlife and roads in urban landscapes. Although road ecology is a growing field of study, relatively little of this research, and relatively few mitigation projects, have been done in urban landscapes. We also draw from the available science on road impacts in rural areas when urban case studies have not fully addressed key topics.

  17. Road following for blindBike: an assistive bike navigation system for low vision persons

    Science.gov (United States)

    Grewe, Lynne; Overell, William

    2017-05-01

    Road Following is a critical component of blindBike, our assistive biking application for the visually impaired. This paper talks about the overall blindBike system and goals prominently featuring Road Following, which is the task of directing the user to follow the right side of the road. This work unlike what is commonly found for self-driving cars does not depend on lane line markings. 2D computer vision techniques are explored to solve the problem of Road Following. Statistical techniques including the use of Gaussian Mixture Models are employed. blindBike is developed as an Android Application and is running on a smartphone device. Other sensors including Gyroscope and GPS are utilized. Both Urban and suburban scenarios are tested and results are given. The success and challenges faced by blindBike's Road Following module are presented along with future avenues of work.

  18. Pattern of Road Traffic Injuries in Rural Bangladesh: Burden Estimates and Risk Factors.

    Science.gov (United States)

    Ul Baset, Md Kamran; Rahman, Aminur; Alonge, Olakunle; Agrawal, Priyanka; Wadhwaniya, Shirin; Rahman, Fazlur

    2017-11-07

    Globally, road traffic injury (RTI) causes 1.3 million deaths annually. Almost 90% of all RTI deaths occur in low- and middle-income countries. RTI is one of the leading causes of death in Bangladesh; the World Health Organization estimated that it kills over 21,000 people in the country annually. This study describes the current magnitude and risk factors of RTI for different age groups in rural Bangladesh. A household census was carried out in 51 unions of seven sub-districts situated in the north and central part of Bangladesh between June and November 2013, covering 1.2 million individuals. Trained data collectors collected information on fatal and nonfatal RTI events through face-to-face interviews using a set of structured pre-tested questionnaires. The recall periods for fatal and non-fatal RTI were one year and six months, respectively. The mortality and morbidity rates due to RTI were 6.8/100,000 population/year and 889/100,000 populations/six months, respectively. RTI mortality and morbidity rates were significantly higher among males compared to females. Deaths and morbidities due to RTI were highest among those in the 25-64 years age group. A higher proportion of morbidity occurred among vehicle passengers (34%) and pedestrians (18%), and more than one-third of the RTI mortality occurred among pedestrians. Twenty percent of all nonfatal RTIs were classified as severe injuries. RTI is a major public health issue in rural Bangladesh. Immediate attention is needed to reduce preventable deaths and morbidities in rural Bangladesh.

  19. Blind spot detection & passive lane change assist systems

    NARCIS (Netherlands)

    Surovtcev, I.

    2015-01-01

    The project goal was design and implementation of proof-of-concept for two systems that aim to tackle the blind spot problem of for the commercial vehicles: Blind Spot Detection and Passive Lane Change Assist functions. The system implementation was done using Rapid Control Prototype (RCP) hardware.

  20. Aberrant Behaviors and Road Accidents among Iranian Truck Drivers, 2010

    Directory of Open Access Journals (Sweden)

    Amir Houshang Mehrparvar

    2011-12-01

    Full Text Available structural dimensions of which as well as technologic failures such as road quality, and tech-nical faults of automobiles, need to be assessed in detail. Iran has the first order in the world for deadly road accidents. This study was designed to assess the association between aberrant behaviors of truck drivers and the incidence of road accidents in Yazd, center of Iran, in 2010.Methods: This cross-sectional descriptive-analytic study was conducted on 300 truck drivers in Yazd. We used 3 questionnaires, including one for demographic data, Driver Behavior Questionnaire (DBQ, and one for drivers' self-evaluation of the of their driving.Results: Five types of the behavior had the highest frequency: Misjudge speed of oncoming vehicle when overtaking.; Deliberately disregard the speed limits late at night or very early in the morning.; Ignore 'give way' signs, and narrowly avoid colliding with traffic having right of way.; Stuck behind a slow-moving vehicle on a two-lane highway, you are driven by frustration to try to overtake in risky circumstances.; Drive with only 'half-an-eye' on the road while looking at a map, changing a cassette or radio channel, etc. The more the driver's driv-ing was influenced by emotional and mental states the more deliberate violations and slips.Conclusion: Among truck drivers, safety has not developed sufficiently, and because of the dangers of road accidents both for the drivers and other people and its economic losses, the importance of the presenting some solutions is completely obvious.

  1. An entropy-based analysis of lane changing behavior: An interactive approach.

    Science.gov (United States)

    Kosun, Caglar; Ozdemir, Serhan

    2017-05-19

    As a novelty, this article proposes the nonadditive entropy framework for the description of driver behaviors during lane changing. The authors also state that this entropy framework governs the lane changing behavior in traffic flow in accordance with the long-range vehicular interactions and traffic safety. The nonadditive entropy framework is the new generalized theory of thermostatistical mechanics. Vehicular interactions during lane changing are considered within this framework. The interactive approach for the lane changing behavior of the drivers is presented in the traffic flow scenarios presented in the article. According to the traffic flow scenarios, 4 categories of traffic flow and driver behaviors are obtained. Through the scenarios, comparative analyses of nonadditive and additive entropy domains are also provided. Two quadrants of the categories belong to the nonadditive entropy; the rest are involved in the additive entropy domain. Driving behaviors are extracted and the scenarios depict that nonadditivity matches safe driving well, whereas additivity corresponds to unsafe driving. Furthermore, the cooperative traffic system is considered in nonadditivity where the long-range interactions are present. However, the uncooperative traffic system falls into the additivity domain. The analyses also state that there would be possible traffic flow transitions among the quadrants. This article shows that lane changing behavior could be generalized as nonadditive, with additivity as a special case, based on the given traffic conditions. The nearest and close neighbor models are well within the conventional additive entropy framework. In this article, both the long-range vehicular interactions and safe driving behavior in traffic are handled in the nonadditive entropy domain. It is also inferred that the Tsallis entropy region would correspond to mandatory lane changing behavior, whereas additive and either the extensive or nonextensive entropy region would

  2. Gap Acceptance During Lane Changes by Large-Truck Drivers-An Image-Based Analysis.

    Science.gov (United States)

    Nobukawa, Kazutoshi; Bao, Shan; LeBlanc, David J; Zhao, Ding; Peng, Huei; Pan, Christopher S

    2016-03-01

    This paper presents an analysis of rearward gap acceptance characteristics of drivers of large trucks in highway lane change scenarios. The range between the vehicles was inferred from camera images using the estimated lane width obtained from the lane tracking camera as the reference. Six-hundred lane change events were acquired from a large-scale naturalistic driving data set. The kinematic variables from the image-based gap analysis were filtered by the weighted linear least squares in order to extrapolate them at the lane change time. In addition, the time-to-collision and required deceleration were computed, and potential safety threshold values are provided. The resulting range and range rate distributions showed directional discrepancies, i.e., in left lane changes, large trucks are often slower than other vehicles in the target lane, whereas they are usually faster in right lane changes. Video observations have confirmed that major motivations for changing lanes are different depending on the direction of move, i.e., moving to the left (faster) lane occurs due to a slower vehicle ahead or a merging vehicle on the right-hand side, whereas right lane changes are frequently made to return to the original lane after passing.

  3. Active training and driving-specific feedback improve older drivers' visual search prior to lane changes.

    Science.gov (United States)

    Lavallière, Martin; Simoneau, Martin; Tremblay, Mathieu; Laurendeau, Denis; Teasdale, Normand

    2012-03-02

    Driving retraining classes may offer an opportunity to attenuate some effects of aging that may alter driving skills. Unfortunately, there is evidence that classroom programs (driving refresher courses) do not improve the driving performance of older drivers. The aim of the current study was to evaluate if simulator training sessions with video-based feedback can modify visual search behaviors of older drivers while changing lanes in urban driving. In order to evaluate the effectiveness of the video-based feedback training, 10 older drivers who received a driving refresher course and feedback about their driving performance were tested with an on-road standardized evaluation before and after participating to a simulator training program (Feedback group). Their results were compared to a Control group (12 older drivers) who received the same refresher course and in-simulator active practice as the Feedback group without receiving driving-specific feedback. After attending the training program, the Control group showed no increase in the frequency of the visual inspection of three regions of interests (rear view and left side mirrors, and blind spot). In contrast, for the Feedback group, combining active training and driving-specific feedbacks increased the frequency of blind spot inspection by 100% (32.3 to 64.9% of verification before changing lanes). These results suggest that simulator training combined with driving-specific feedbacks helped older drivers to improve their visual inspection strategies, and that in-simulator training transferred positively to on-road driving. In order to be effective, it is claimed that driving programs should include active practice sessions with driving-specific feedbacks. Simulators offer a unique environment for developing such programs adapted to older drivers' needs.

  4. An Optimization Model for the Selection of Bus-Only Lanes in a City.

    Science.gov (United States)

    Chen, Qun

    2015-01-01

    The planning of urban bus-only lane networks is an important measure to improve bus service and bus priority. To determine the effective arrangement of bus-only lanes, a bi-level programming model for urban bus lane layout is developed in this study that considers accessibility and budget constraints. The goal of the upper-level model is to minimize the total travel time, and the lower-level model is a capacity-constrained traffic assignment model that describes the passenger flow assignment on bus lines, in which the priority sequence of the transfer times is reflected in the passengers' route-choice behaviors. Using the proposed bi-level programming model, optimal bus lines are selected from a set of candidate bus lines; thus, the corresponding bus lane network on which the selected bus lines run is determined. The solution method using a genetic algorithm in the bi-level programming model is developed, and two numerical examples are investigated to demonstrate the efficacy of the proposed model.

  5. An Optimization Model for the Selection of Bus-Only Lanes in a City.

    Directory of Open Access Journals (Sweden)

    Qun Chen

    Full Text Available The planning of urban bus-only lane networks is an important measure to improve bus service and bus priority. To determine the effective arrangement of bus-only lanes, a bi-level programming model for urban bus lane layout is developed in this study that considers accessibility and budget constraints. The goal of the upper-level model is to minimize the total travel time, and the lower-level model is a capacity-constrained traffic assignment model that describes the passenger flow assignment on bus lines, in which the priority sequence of the transfer times is reflected in the passengers' route-choice behaviors. Using the proposed bi-level programming model, optimal bus lines are selected from a set of candidate bus lines; thus, the corresponding bus lane network on which the selected bus lines run is determined. The solution method using a genetic algorithm in the bi-level programming model is developed, and two numerical examples are investigated to demonstrate the efficacy of the proposed model.

  6. Optimizing traffic flow efficiency by controlling lane changes: collective, group and user optima

    NARCIS (Netherlands)

    Yao, S.; Knoop, V.L.; van Arem, B.

    2017-01-01

    Lane changes can lead to disturbances in traffic flow, whilst the uneven distribution of traffic over different lanes as a result of lane changes can also lead to instabilities and congestion on one specific lane. Therefore, giving advice on lane change can be beneficial for both individual drivers

  7. Effects of Potential Lane-Changing Probability on Uniform Flow

    International Nuclear Information System (INIS)

    Tang Tieqiao; Huang Haijun; Shang Huayan

    2010-01-01

    In this paper, we use the car-following model with the anticipation effect of the potential lane-changing probability (Acta Mech. Sin. 24 (2008) 399) to investigate the effects of the potential lane-changing probability on uniform flow. The analytical and numerical results show that the potential lane-changing probability can enhance the speed and flow of uniform flow and that their increments are related to the density.

  8. Gap Acceptance During Lane Changes by Large-Truck Drivers—An Image-Based Analysis

    Science.gov (United States)

    Nobukawa, Kazutoshi; Bao, Shan; LeBlanc, David J.; Zhao, Ding; Peng, Huei; Pan, Christopher S.

    2016-01-01

    This paper presents an analysis of rearward gap acceptance characteristics of drivers of large trucks in highway lane change scenarios. The range between the vehicles was inferred from camera images using the estimated lane width obtained from the lane tracking camera as the reference. Six-hundred lane change events were acquired from a large-scale naturalistic driving data set. The kinematic variables from the image-based gap analysis were filtered by the weighted linear least squares in order to extrapolate them at the lane change time. In addition, the time-to-collision and required deceleration were computed, and potential safety threshold values are provided. The resulting range and range rate distributions showed directional discrepancies, i.e., in left lane changes, large trucks are often slower than other vehicles in the target lane, whereas they are usually faster in right lane changes. Video observations have confirmed that major motivations for changing lanes are different depending on the direction of move, i.e., moving to the left (faster) lane occurs due to a slower vehicle ahead or a merging vehicle on the right-hand side, whereas right lane changes are frequently made to return to the original lane after passing. PMID:26924947

  9. Assessing the safety of the road network : a simple method.

    NARCIS (Netherlands)

    Janssen, S.T.M.C.

    1993-01-01

    Research by the SWOV Institute for Road Safety Research in The Netherlands assessing the safety of the Dutch road network is presented. In The Netherlands urban and rural roads and motorways are used roughly equally, however accident rates vary greatly. These are discussed in this paper. Tables show

  10. Lane-changing behavior and its effect on energy dissipation using full velocity difference model

    Science.gov (United States)

    Wang, Jian; Ding, Jian-Xun; Shi, Qin; Kühne, Reinhart D.

    2016-07-01

    In real urban traffic, roadways are usually multilane with lane-specific velocity limits. Most previous researches are derived from single-lane car-following theory which in the past years has been extensively investigated and applied. In this paper, we extend the continuous single-lane car-following model (full velocity difference model) to simulate the three-lane-changing behavior on an urban roadway which consists of three lanes. To meet incentive and security requirements, a comprehensive lane-changing rule set is constructed, taking safety distance and velocity difference into consideration and setting lane-specific speed restriction for each lane. We also investigate the effect of lane-changing behavior on distribution of cars, velocity, headway, fundamental diagram of traffic and energy dissipation. Simulation results have demonstrated asymmetric lane-changing “attraction” on changeable lane-specific speed-limited roadway, which leads to dramatically increasing energy dissipation.

  11. Long-term sodium chloride retention in a rural watershed: legacy effects of road salt on streamwater concentration.

    Science.gov (United States)

    Kelly, Victoria R; Lovett, Gary M; Weathers, Kathleen C; Findlay, Stuart E G; Strayer, David L; Burns, David I; Likens, Gene E

    2008-01-15

    Sodium and chloride concentrations and export increased from 1986 to 2005 in a rural stream in southeastern New York. Concentrations increased 1.5 mg/L per year (chloride) and 0.9 mg/L per year (sodium), and export increased 33,000 kg/year (chloride) and 20,000 kg/year (sodium) during this period. We estimate that salt used for deicing accounted for 91% of the sodium chloride input to the watershed, while sewage and water softeners accounted for less than 10% of the input. Road salt use in the watershed did not increase during the study, but sodium and chloride from sewage and water softeners is likely to have increased slightly due to a small increase in population. Increased input from sewage and water softeners cannot account for the increase in concentration and export from the watershed. Model results suggest that the increase in streamwater concentration and export was likely due to a lag effect of long-term road salt use and subsurface buildup.

  12. Effects of age and illumination on night driving: a road test.

    Science.gov (United States)

    Owens, D Alfred; Wood, Joanne M; Owens, Justin M

    2007-12-01

    This study investigated the effects of drivers' age and low light on speed, lane keeping, and visual recognition of typical roadway stimuli. Poor visibility, which is exacerbated by age-related changes in vision, is a leading contributor to fatal nighttime crashes. There is little evidence, however, concerning the extent to which drivers recognize and compensate for their visual limitations at night. Young, middle-aged, and elder participants drove on a closed road course in day and night conditions at a "comfortable" speed without speedometer information. During night tests, headlight intensity was varied over a range of 1.5 log units using neutral density filters. Average speed and recognition of road signs decreased significantly as functions of increased age and reduced illumination. Recognition of pedestrians at night was significantly enhanced by retroreflective markings of limb joints as compared with markings of the torso, and this benefit was greater for middle-aged and elder drivers. Lane keeping showed nonlinear effects of lighting, which interacted with task conditions and drivers' lateral bias, indicating that older drivers drove more cautiously in low light. Consistent with the hypothesis that drivers misjudge their visual abilities at night, participants of all age groups failed to compensate fully for diminished visual recognition abilities in low light, although older drivers behaved more cautiously than the younger groups. These findings highlight the importance of educating all road users about the limitations of night vision and provide new evidence that retroreflective markings of the limbs can be of great benefit to pedestrians' safety at night.

  13. Study of current and planned high occupancy vehicle lane use: performance and prospects

    Energy Technology Data Exchange (ETDEWEB)

    Southworth, F.; Westbrook, F.

    1985-12-01

    This report details the results of a nationwide study of HOV lanes: their characteristics and performance as traffic congestion mitigating and rideshare enhancing facilities. The study took the form of telephone interviews with a variety of planning agencies in each of the 48 contiguous states and Hawaii over the period April through June 1985, with subsequent receipt of the most current documentation on regional HOV lane operations. The most up-to-date evidence on each lane's performance is presented: its hourly and peak period person throughput vis-a-vis the highway's adjacent, conventional mixed traffic lane(s), its vehicle throughput and occupancy, travel speed and travel time savings for HOVs, lane rule violation rates, lane construction and maintenance costs and accident data. Estimates are provided of the growth in ridesharing over the life of the HOV-only lanes, of the number of vehicles removed from the highway through ridesharing, and of the subsequent fuel savings attributable to HOV lane projects. The relationship between bus patronage and carpool/vanpool mode adoption is looked at, and it is concluded that both forms of HOV can do well on properly planned lanes. The authors also point out the very partial nature of the existing evidence upon which to base HOV lane project evaluation, and the subsequent difficulty associated with ''selling'' the HOV lane concept to many planners and members of the public. They identify those characteristics associated with clearly successful HOV lane projects. Finally, the current state of planning for new HOV lanes in cities around the nation is described, and the major reasons given for rejection or abandonment of HOV lane projects are discussed.

  14. Kansas Non-State Road System

    Data.gov (United States)

    Kansas Data Access and Support Center — This dataset is a single centerline road network representation of 120,000 miles of the Kansas non-state highway system with limited attribution. It includes rural...

  15. MILLS B. LANE, JR. AND ENTERPRISE IN A NEW SOUTH

    Directory of Open Access Journals (Sweden)

    Randall L. Patton

    2009-01-01

    Full Text Available For a century, Citizens & Southern Bank was a fixture in Georgia. In 1991, the C&S brand name disappeared in a merger with North Carolina National Bank. This was one of the bittersweet consequences of the slow, confusing swirl of bank deregulation after 1970, when institutions such as C&S simply disappeared, swallowed by the “winners” in the new competitive environment of interstate banking in the 1980s and 1990s. Even earlier, however, the Lane family had ceased to control the bank started by Mills Lane, Sr. in 1891. Mills B. Lane, Jr. was the last member of the Lane family to run C&S. After his retirement in 1973, Mills handpicked his successor and tried to retain some influence, but the bank began slipping away from the Lanes. By the early 80s, a decade before Hugh McColl’s NCNB acquired C&S, Mills Lane, Jr. was deeply alienated from the institution that had been, according to many, “Georgia’s cornerstone bank.”

  16. Large Gaps in Canopy Reduce Road Crossing by a Gliding Mammal

    Directory of Open Access Journals (Sweden)

    Rodney van der Ree

    2010-12-01

    Full Text Available Roads and traffic reduce landscape connectivity and increase rates of mortality for many species of wildlife. Species that glide from tree to tree may be strongly affected by roads and traffic if the size of the gap between trees exceeds their gliding capability. Not only are wide roads likely to reduce crossing rates, but mortality may also be increased if gliders that do cross have poor landing opportunities. The road-crossing behavior of 47 squirrel gliders (Petaurus norfolcensis was investigated in southeast Australia using radio-tracking. The proportion of gliders crossing one or both roadways of a freeway where trees were present or absent from the center median was compared to that at single-lane country roads (control. The proportion of gliders crossing the road at control sites (77% was similar to the proportion that crossed one or both roadways at the freeway with trees in the median (67%, whereas only a single male (6% crossed the freeway where trees were absent from the median. The frequency of crossing for each individual was also similar at control sites and freeway sites with trees in the median. The almost complete lack of crossing at sites where trees were absent from the median was attributed to the wider gap in canopy (50 - 64 m vs. 5 - 13 m at sites with trees in the median. This suggests that traffic volume, up to 5,000 vehicles per day on each roadway, and the other characteristics of the freeway we studied are not in themselves complete deterrents to road crossing by squirrel gliders. This study demonstrates that retaining and facilitating the growth of tall trees in the center median of two-way roads may mitigate the barrier effect of roads on gliders, thus contributing positively to mobility and potentially to connectivity. This information will be essential for the assessment of road impacts on gliding species using population viability models.

  17. A Congestion Control System Based on VANET for Small Length Roads

    Directory of Open Access Journals (Sweden)

    Ruchin Jain

    2018-01-01

    Full Text Available As vehicle population has been increasing on a daily basis, this leads towards increased number of accidents. To overcome this issue, Vehicular Ad Hoc Network (VANET has come up with lot of novel ideas such as vehicular communication, navigation and traffic controlling. In this study, the main focus is on congestion control at the intersections which result from unclear ahead. For this purpose, a city lane and intersection model has been proposed to manage vehicle mobility. It shows the actual vehicle to vehicle and vehicle to traffic infrastructure communication. The experiment was conducted using Network Simulator 2 (NS 2. The implementation required modelling the road side unit, traffic control unit, and on-board unit along the roadside. In the simulation, including traffic volume, the distance between two signals, end-to-end delay, packet delivery ratio, throughput and packet lost were taken into consideration. These parameters ensure efficient communication between the traffic signals. This results in improved congestion control and road safety, since the vehicles will be signalled not to enter the junction box and information about other vehicles.

  18. Prediction of Chinese Drivers' Intentions to Park Illegally in Emergency Lanes: An Application of the Theory of Planned Behavior.

    Science.gov (United States)

    Zheng, Yubing; Ma, Yang; Guo, Lixin; Cheng, Jianchuan; Zhang, Yunlong

    2018-06-21

    Illegal parking in emergency lanes (paved highway shoulders) is becoming a serious road safety issue in China. The aim of this study was: 1) to examine the utility of the theory of planned behavior (TPB) extended with descriptive norm, past behavior, facilitating and deterring circumstances, sensation seeking and invulnerability in predicting Chinese drivers' intentions in illegal emergency lane parking; 2) to investigate whether respondents' demographic characteristics would impact their views towards the behavior and predictive patterns of intentions; 3) to identify significant predictors of intentions. In this cross-sectional study, eligible respondents were all qualified Chinese drivers. A self-administered questionnaire was employed to collect data including demographic information, descriptive norm, past behavior, facilitating and deterring circumstances, sensation seeking and scenario-based invulnerability combined with TPB constructs. Descriptive statistics, MANOVAs and a series of hierarchical multiple linear regression analyses were conducted in SPSS. A total of 435 qualified drivers (234 males and 201 females) with a mean age of 35.2 years (S.D.=10.3) were included in analysis. The descriptive analysis showed that most participants reported weak intentions (M = 2.35) to park illegally in emergency lanes with negative attitude (M = 3.19), low perceived support (M = 2.91) and high control (M = 5.08) over the behavior. The model succeeded in explaining 64% of the variance in intentions for the whole sample, and principal TPB components accounted for 21% of variance in intentions after demographic variables were controlled. MANOVAs revealed that significant differences of respondents' opinions towards illegal emergency lane parking were only found between better-educated drivers (with college education background) and less-educated ones. Separate regression analyses revealed that predictive pattern of better-educated participants also

  19. Lane changing and speed interaction on freeways : An analytical microscopic study

    NARCIS (Netherlands)

    Keyvan Ekbatani, M.; Grebert, V.; Daamen, W.; Knoop, V.L.

    2015-01-01

    Understanding the influence of lane changing manoeuvre on the capacity, stability, and breakdown of traffic flows is a crucial issue. In a recent study, four distinct lane change strategies on freeways have been empirically found: (1) Speed Leading; (2) Speed Leading with Overtaking; (3) Lane

  20. Evaluating the employment-generating impact of rural roads in Nicaragua

    DEFF Research Database (Denmark)

    Rand, John

    2011-01-01

    This paper analyses the employment-generating impact of a tertiary road project in Nicaragua, applying a matched double-difference approach to control for initial conditions and time variant factors that simultaneously influence the placement of roads and subsequent employment growth rates. Results......, more integrated road networks....

  1. Active training and driving-specific feedback improve older drivers' visual search prior to lane changes

    Directory of Open Access Journals (Sweden)

    Lavallière Martin

    2012-03-01

    Full Text Available Abstract Background Driving retraining classes may offer an opportunity to attenuate some effects of aging that may alter driving skills. Unfortunately, there is evidence that classroom programs (driving refresher courses do not improve the driving performance of older drivers. The aim of the current study was to evaluate if simulator training sessions with video-based feedback can modify visual search behaviors of older drivers while changing lanes in urban driving. Methods In order to evaluate the effectiveness of the video-based feedback training, 10 older drivers who received a driving refresher course and feedback about their driving performance were tested with an on-road standardized evaluation before and after participating to a simulator training program (Feedback group. Their results were compared to a Control group (12 older drivers who received the same refresher course and in-simulator active practice as the Feedback group without receiving driving-specific feedback. Results After attending the training program, the Control group showed no increase in the frequency of the visual inspection of three regions of interests (rear view and left side mirrors, and blind spot. In contrast, for the Feedback group, combining active training and driving-specific feedbacks increased the frequency of blind spot inspection by 100% (32.3 to 64.9% of verification before changing lanes. Conclusions These results suggest that simulator training combined with driving-specific feedbacks helped older drivers to improve their visual inspection strategies, and that in-simulator training transferred positively to on-road driving. In order to be effective, it is claimed that driving programs should include active practice sessions with driving-specific feedbacks. Simulators offer a unique environment for developing such programs adapted to older drivers' needs.

  2. AN EPIDEMIOLOGICAL STUDY OF ROAD TRAFFIC ACCIDENT CASES AT A TERTIARY CARE HOSPITAL IN RURAL HARYANA

    Directory of Open Access Journals (Sweden)

    Abhishek Singh

    2011-12-01

    Full Text Available Background- Accidents occur not only due to ignorance but also due to carelessness, thoughtlessness and over confidence. Human, vehicular and environmental factors play role before, during and after a Road Traffic Accidents (RTA. Road traffic injuries are partially predictable and hence preventable. Objectives- To study the pattern of road traffic accidents, socio demographic profile of road traffic injury victims seeking care at Maharishi Markandeshwar Institute of Medical Sciences And Research, Mullana and to study the antecedent factors influencing the road traffic accidents. Material and Methods-The present cross-sectional study was carried out at Maharishi Markandeshwar Institute of Medical Sciences and Research (MMIMSR, Mullana (Ambala. All the victims who reported to MMIMSR emergency and various OPD clinics of the institute between September 2009 to February 2011 were included in the study. Various parameters like age and sex distribution, time of occurrence, protective gears worn, injuries sustained, receipt of First -Aid, alcohol consumption, category of road user, vehicles involved in RTA, types of RTA, road conditions, environmental conditions etc were studied and valid conclusions were drawn. Results- There was a marked male preponderance (88.77 % with maximum involvement of younger age groups. Most of the accidents had taken place in the evening hours (6 pm -12 midnight. The vulnerable road users like motorized two wheeler, LMV and pedestrians constituted 41.52%, 19.39% and 13.41% respectively. Only 158 of 545 two-wheeler users wore a helmet at the time of injury. 16.24% of drivers did not have a valid driving license. Not using indicator lights and not following speed limits were two most common factors responsible for these RTA.

  3. The use of yellow longitudinal markings on roads with two-directional traffic. Contribution to OECD Research Group TS 304 "Improving road safety at night".

    NARCIS (Netherlands)

    Schreuder, D.A.

    1978-01-01

    The question is posed whether the application of a colour difference for the central line on the road is the best solution available for the coding of the categories of road. It has been proposed to apply yellow centre lines on roads with two-way traffic and white centre lines on roads with

  4. Towards the Mainstreaming of an Approach to Include Social Benefits Within Road Appraisal : A Case Study from Uganda

    OpenAIRE

    Odoki, Jennaro B.; Ahmed, Farhad; Taylor, Gary; Okello, Sunday A.

    2008-01-01

    Developing countries dedicate a considerable share of total infrastructure investment to roads. The adoption in 2000 of the Millennium Development Goals and an increasing emphasis on justifying road investments in terms of their contribution to poverty reduction have directed considerable attention to low volume rural roads. Often the poorest of the poor live in remote rural areas and impr...

  5. Parameterizing road construction in route-based road weather models: can ground-penetrating radar provide any answers?

    International Nuclear Information System (INIS)

    Hammond, D S; Chapman, L; Thornes, J E

    2011-01-01

    A ground-penetrating radar (GPR) survey of a 32 km mixed urban and rural study route is undertaken to assess the usefulness of GPR as a tool for parameterizing road construction in a route-based road weather forecast model. It is shown that GPR can easily identify even the smallest of bridges along the route, which previous thermal mapping surveys have identified as thermal singularities with implications for winter road maintenance. Using individual GPR traces measured at each forecast point along the route, an inflexion point detection algorithm attempts to identify the depth of the uppermost subsurface layers at each forecast point for use in a road weather model instead of existing ordinal road-type classifications. This approach has the potential to allow high resolution modelling of road construction and bridge decks on a scale previously not possible within a road weather model, but initial results reveal that significant future research will be required to unlock the full potential that this technology can bring to the road weather industry. (technical design note)

  6. Evaluating the Influence of Road Lighting on Traffic Safety at Accesses Using An Artificial Neural Network.

    Science.gov (United States)

    Xu, Yueru; Ye, Zhirui; Wang, Yuan; Wang, Chao; Sun, Cuicui

    2018-05-18

    This paper focuses on the effect of road lighting on road safety at accesses and tries to quantitatively analyze the relationship between road lighting and road safety. An Artificial Neural Network (ANN) was applied in this study. This method is one of the most popular machine-learning methods in recent years and does not require any pre-defined assumptions. This method was applied using field data collected from ten road segments in Nanjing, Jiangsu Province, China. The results show that the impact of road lighting on road safety at accesses is significant. In addition, road lighting has greater influence when vehicle speeds are higher or the number of lanes is larger. A threshold illuminance was also found in this paper, and the results show that the safety level at accesses will become stable when reaching this value. The improvement of illuminance can decrease the speed variation among vehicles and improve the safety level. In addition, high-grade roads need better illuminance at accesses. A threshold value can also be obtained based on related variables and used to develop scientific guidelines for traffic management organizations.

  7. Recognition of Damaged Arrow-Road Markings by Visible Light Camera Sensor Based on Convolutional Neural Network

    Directory of Open Access Journals (Sweden)

    Husan Vokhidov

    2016-12-01

    Full Text Available Automobile driver information as displayed on marked road signs indicates the state of the road, traffic conditions, proximity to schools, etc. These signs are important to insure the safety of the driver and pedestrians. They are also important input to the automated advanced driver assistance system (ADAS, installed in many automobiles. Over time, the arrow-road markings may be eroded or otherwise damaged by automobile contact, making it difficult for the driver to correctly identify the marking. Failure to properly identify an arrow-road marker creates a dangerous situation that may result in traffic accidents or pedestrian injury. Very little research exists that studies the problem of automated identification of damaged arrow-road marking painted on the road. In this study, we propose a method that uses a convolutional neural network (CNN to recognize six types of arrow-road markings, possibly damaged, by visible light camera sensor. Experimental results with six databases of Road marking dataset, KITTI dataset, Málaga dataset 2009, Málaga urban dataset, Naver street view dataset, and Road/Lane detection evaluation 2013 dataset, show that our method outperforms conventional methods.

  8. Recognition of Damaged Arrow-Road Markings by Visible Light Camera Sensor Based on Convolutional Neural Network.

    Science.gov (United States)

    Vokhidov, Husan; Hong, Hyung Gil; Kang, Jin Kyu; Hoang, Toan Minh; Park, Kang Ryoung

    2016-12-16

    Automobile driver information as displayed on marked road signs indicates the state of the road, traffic conditions, proximity to schools, etc. These signs are important to insure the safety of the driver and pedestrians. They are also important input to the automated advanced driver assistance system (ADAS), installed in many automobiles. Over time, the arrow-road markings may be eroded or otherwise damaged by automobile contact, making it difficult for the driver to correctly identify the marking. Failure to properly identify an arrow-road marker creates a dangerous situation that may result in traffic accidents or pedestrian injury. Very little research exists that studies the problem of automated identification of damaged arrow-road marking painted on the road. In this study, we propose a method that uses a convolutional neural network (CNN) to recognize six types of arrow-road markings, possibly damaged, by visible light camera sensor. Experimental results with six databases of Road marking dataset, KITTI dataset, Málaga dataset 2009, Málaga urban dataset, Naver street view dataset, and Road/Lane detection evaluation 2013 dataset, show that our method outperforms conventional methods.

  9. Recognition of Damaged Arrow-Road Markings by Visible Light Camera Sensor Based on Convolutional Neural Network

    Science.gov (United States)

    Vokhidov, Husan; Hong, Hyung Gil; Kang, Jin Kyu; Hoang, Toan Minh; Park, Kang Ryoung

    2016-01-01

    Automobile driver information as displayed on marked road signs indicates the state of the road, traffic conditions, proximity to schools, etc. These signs are important to insure the safety of the driver and pedestrians. They are also important input to the automated advanced driver assistance system (ADAS), installed in many automobiles. Over time, the arrow-road markings may be eroded or otherwise damaged by automobile contact, making it difficult for the driver to correctly identify the marking. Failure to properly identify an arrow-road marker creates a dangerous situation that may result in traffic accidents or pedestrian injury. Very little research exists that studies the problem of automated identification of damaged arrow-road marking painted on the road. In this study, we propose a method that uses a convolutional neural network (CNN) to recognize six types of arrow-road markings, possibly damaged, by visible light camera sensor. Experimental results with six databases of Road marking dataset, KITTI dataset, Málaga dataset 2009, Málaga urban dataset, Naver street view dataset, and Road/Lane detection evaluation 2013 dataset, show that our method outperforms conventional methods. PMID:27999301

  10. “Rejecting the inevitability of poverty”: Empower women for sustainable rural livelihoods through community-based employment intensive rural infrastructure maintenance projects

    CSIR Research Space (South Africa)

    Mashiri, M

    2008-11-01

    Full Text Available This paper discuses the extent to which employment-intensive rural infrastructure maintenance projects can be used as a tool to empower women to achieve sustainable rural livelihoods using Siyatentela rural road maintenance program in Mpumalanga...

  11. High lane density slab-gel electrophoresis using micromachined instrumentation.

    Science.gov (United States)

    Papautsky, I; Mohanty, S; Weiss, R; Frazier, A B

    2001-10-01

    In this paper, micromachined pipette arrays (MPAs) and microcombs were studied as a means of enabling high lane density gel electrophoresis. The MPA provide a miniaturized format to interface sub-microliter volumes of samples between macroscale sample preparation formats and microscale biochemical analysis systems. The microcombs provide a means of creating sample loading wells in the gel material on the same center-to-center spacing as the MPAs. Together, the two micromachined instruments provide an alternative to current combs and pipetting technologies used for creating sample loading wells and sample delivery in gel electrophoresis systems. Using three designs for the microcomb-MPA pair, center-to-center spacings of 1.0 mm, 500 microm, and 250 microm are studied. The results demonstrate an approximate 10-fold increase in lane density and a 10-fold reduction in sample size from 5 microL to 500 pL. As a result, the number of theoretical plates has increased 2.5-fold, while system resolution has increased 1.5-fold over the conventional agarose gel systems. An examination of changes in resolution across the width of individual separation lanes in both systems revealed dependence in the case of the conventional gels and no dependence for the gels loaded with the micromachined instrumentation.

  12. Towards appropriate standards for rural roads: discussion document

    CSIR Research Space (South Africa)

    van Zyl, GD

    1993-03-01

    Full Text Available signs 6-7 6.9 Road markings 6-11 6.10 Delineation 6-11 6.11 References 6·12 '~ CHAPTER 7: SAFETY ASPECTS 7.1 Introduction 7-1 7.2 Design and construction 7-2 7.3 Maintenance and rehabilitation 7-9 7.4 Legal aspects 7-11 7.5 References 7... The major comment on Chapter3 : Geometric D.::sign relates to the philosophy adopted namely where it is proposed thai the operating speed approaches the design speed against the existing practice where there is a marked difference between the two speeds...

  13. Accelerated Lane-Changing Trajectory Planning of Automated Vehicles with Vehicle-to-Vehicle Collaboration

    Directory of Open Access Journals (Sweden)

    Haijian Bai

    2017-01-01

    Full Text Available Considering the complexity of lane changing using automated vehicles and the frequency of turning lanes in city settings, this paper aims to generate an accelerated lane-changing trajectory using vehicle-to-vehicle collaboration (V2VC. Based on the characteristics of accelerated lane changing, we used a polynomial method and cooperative strategies for trajectory planning to establish a lane-changing model under different degrees of collaboration with the following vehicle in the target lane by considering vehicle kinematics and comfort requirements. Furthermore, considering the shortcomings of the traditional elliptical vehicle and round vehicle models, we established a rectangular vehicle model with collision boundary conditions by analysing the relationships between the possible collision points and the outline of the vehicle. Then, we established a simulation model for the accelerated lane-changing process in different environments under different degrees of collaboration. The results show that, by using V2VC, we can achieve safe accelerated lane-changing trajectories and simultaneously satisfy the requirements of vehicle kinematics and comfort control.

  14. Towards trusted trade-lanes

    NARCIS (Netherlands)

    Hulstijn, J.; Hofman, W.; Zomer, G.; Tan, Y.H.

    2016-01-01

    Customs administrations are exploring system-based approaches to regulatory supervision, taking the entire set of controls in a process into account. In addition to Trusted Traders, which are recognized by a certification process, customs are considering to identify so called Trusted Trade Lanes:

  15. Effect of speed hump characteristics on pavement condition

    Directory of Open Access Journals (Sweden)

    Talaat Ali Abdel-Wahed

    2017-02-01

    Full Text Available Speed humps are the most common type of traffic calming devices due to their low cost and easy installation. However, in many Egyptian roads, considerable number of these humps is randomly placed without proper engineering studies and justifications. Deterioration of pavement condition is observed near these humps. This paper presents a case study applied to collect and analyze visual inspection data for the reason of evaluating the impact of speed humps on pavement condition on intercity rural roads. The paper used 52 speed humps located in an intercity two-lane, two-way road that connects two cities, Tahta and Gerga, in Upper Egypt. The total length of this road is about 34 km. Pavement condition index (PCI, in road sections, near speed humps in the two directions of travel were calculated from the visual inspection measurements. The characteristics of each speed hump (width, height, and distance from preceding hump were measured. Using statistical analyses, the correlations between the pavement conditions and hump characteristics were examined. Regression analysis models were developed to represent the relationships between pavement conditions and hump characteristics. Generally, the results proved that the pavement conditions are greatly influenced by the presence of speed humps and hump characteristics.

  16. Rural transformations in the context of changing rural-urban connections

    DEFF Research Database (Denmark)

    Birch-Thomsen, Torben; Ørtenblad, Sinne Borby; Msese, Lukelo

    , the infrastructure, including road systems and means of communication, has in general increased and improved. This development has among a number of other things caused changing patterns of mobility. These changes are highly interrelated and connected to changing rural-urban linkages, which include flows of people......, capital, resources, agricultural commodities, goods, services, technology and information, between rural and urban locations. We emphasize that the rural-urban connections go beyond the spatial dichotomy and that the linkages often occur in a dynamic rural-urban continuum. Influenced by these changes......, this paper sets out to elucidate patterns and dynamics of rural transformation in Tanzania in the context of changing rural-urban linkages by presenting data from a particularly dynamic region; namely Njombe Region in the Southern Highlands of Tanzania. Based on fieldwork conducted during 2014 and 2015...

  17. Toward a best practice model for managed lanes in Texas.

    Science.gov (United States)

    2013-09-01

    Increasing implementation of managed lanes in the : United States : Katy Freeway Managed Lanes : (KML) offers lessons learned : for other projects : First operational, multilane, : variably priced, managed facility : in Texas : Became oper...

  18. Development of a lane change risk index using vehicle trajectory data.

    Science.gov (United States)

    Park, Hyunjin; Oh, Cheol; Moon, Jaepil; Kim, Seongho

    2018-01-01

    Surrogate safety measures (SSMs) have been widely used to evaluate crash potential, which is fundamental for the development of effective safety countermeasures. Unlike existing SSMs, which are mainly focused on the evaluation of longitudinal vehicle maneuvering leading to rear-end crashes, this study proposes a new method for estimating crash risk while a subject vehicle changes lanes, referred to as the lane change risk index (LCRI). A novel feature of the proposed methodology is its incorporation of the amount of exposure time to potential crash and the expected crash severity level by applying a fault tree analysis (FTA) to the evaluation framework. Vehicle interactions between a subject vehicle and adjacent vehicles in the starting lane and the target lane are evaluated in terms of crash potential during lane change. Vehicle trajectory data obtained from a traffic stream, photographed using a drone flown over a freeway segment, is used to investigate the applicability of the proposed methodology. This study compares the characteristics of compulsory and discretionary lane changes observed in a work zone section and a general section of a freeway using the LCRI. It is expected that the outcome of this study will be valuable in evaluating the effectiveness of various traffic operations and control strategies in terms of lane change safety. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. A multi criteria analog model for assessing the vulnerability of rural catchments to road spills of hazardous substances

    Energy Technology Data Exchange (ETDEWEB)

    Siqueira, Hygor Evangelista; Pissarra, Teresa Cristina Tarlé [Departamento de Engenharia Rural, Faculdade de Ciências Agrárias e Veterinárias, Universidade Estadual Paulista, Jaboticabal (Brazil); Farias do Valle Junior, Renato [Laboratório de Geoprocessamento, Instituto Federal do Triângulo Mineiro, Campus Uberaba, Uberaba (Brazil); Fernandes, Luis Filipe Sanches [Centro de Investigação e Tecnologias Agroambientais e Biológicas, Universidade de Trás-os-Montes e Alto Douro, Ap 1013, 5001–801 Vila Real (Portugal); Pacheco, Fernando António Leal, E-mail: fpacheco@utad.pt [Centro de Química de Vila Real, Universidade de Trás-os-Montes e Alto Douro, Ap 1013, 5001–801 Vila Real (Portugal)

    2017-05-15

    Area (APA), located in the Uberaba region, state of Minas Gerais, Brazil. In this region, the risk of accidents causing chemical spills is preoccupying because large quantities of dangerous materials are transported in two important distribution highways while the APA is fundamental for the protection of water resources, the riverine ecosystems and remnants of native vegetation. In some tested scenarios, model results show 60% of vulnerable areas within the studied area. The most sensitive parameter to vulnerability is soil type. To prevent soils from contamination, specific measures were proposed involving minimization of land use conflicts that would presumably raise the soil's organic matter and in the sequel restore the soil's structural functions. Additionally, the present study proposed the preservation and reinforcement of riparian forests as one measure to protect the quality of surface water. - Highlights: • A multi criteria analog model was developed to assess rural catchment vulnerability along roads. • Model parameters were defined by analogy with urban wash-off equations and routing algorithms. • The model mixes up various biophysical and socio-economic parameters. • Model application was based on a scenario analysis. • The study is focused on the Environmental Protection Area of Uberaba River, Brazil.

  20. A multi criteria analog model for assessing the vulnerability of rural catchments to road spills of hazardous substances

    International Nuclear Information System (INIS)

    Siqueira, Hygor Evangelista; Pissarra, Teresa Cristina Tarlé; Farias do Valle Junior, Renato; Fernandes, Luis Filipe Sanches; Pacheco, Fernando António Leal

    2017-01-01

    Area (APA), located in the Uberaba region, state of Minas Gerais, Brazil. In this region, the risk of accidents causing chemical spills is preoccupying because large quantities of dangerous materials are transported in two important distribution highways while the APA is fundamental for the protection of water resources, the riverine ecosystems and remnants of native vegetation. In some tested scenarios, model results show 60% of vulnerable areas within the studied area. The most sensitive parameter to vulnerability is soil type. To prevent soils from contamination, specific measures were proposed involving minimization of land use conflicts that would presumably raise the soil's organic matter and in the sequel restore the soil's structural functions. Additionally, the present study proposed the preservation and reinforcement of riparian forests as one measure to protect the quality of surface water. - Highlights: • A multi criteria analog model was developed to assess rural catchment vulnerability along roads. • Model parameters were defined by analogy with urban wash-off equations and routing algorithms. • The model mixes up various biophysical and socio-economic parameters. • Model application was based on a scenario analysis. • The study is focused on the Environmental Protection Area of Uberaba River, Brazil.

  1. Road Maintenance in Africa: Approaches and Perspectives

    Directory of Open Access Journals (Sweden)

    M Mostafa Hassan

    2018-01-01

    Full Text Available In Africa, roads are the dominant mode of passenger and freight transport, for which the need is growing rapidly. It is noticeable that most of the African countries do not do enough to ensure the sustainability of road infrastructure as it has been widely reported that roads are affected, to varying degrees, by premature deterioration. Most of the African countries have adopted institutional reforms, notably entailing the creation of road funds and road agencies, and made significant progress on road maintenance. However, many challenges remain to be addressed in all of them to ensure appropriate maintenance. Although spending on road maintenance has increased over time in all African countries it remains insufficient to cover the needs. Poorly maintained roads constrain mobility, significantly raise vehicle operating costs, increase accident rates and their associated human and property costs, and aggravate isolation, poverty, poor health, and illiteracy in rural communities. This paper focuses, in particular, on road maintenance in some African countries considering types of road maintenance and the different approaches aiming at a comparison to reflect on similarities and differences.

  2. Road Maintenance in Africa: Approaches and Perspectives

    Science.gov (United States)

    M, Mostafa Hassan

    2018-06-01

    In Africa, roads are the dominant mode of passenger and freight transport, for which the need is growing rapidly. It is noticeable that most of the African countries do not do enough to ensure the sustainability of road infrastructure as it has been widely reported that roads are affected, to varying degrees, by premature deterioration. Most of the African countries have adopted institutional reforms, notably entailing the creation of road funds and road agencies, and made significant progress on road maintenance. However, many challenges remain to be addressed in all of them to ensure appropriate maintenance. Although spending on road maintenance has increased over time in all African countries it remains insufficient to cover the needs. Poorly maintained roads constrain mobility, significantly raise vehicle operating costs, increase accident rates and their associated human and property costs, and aggravate isolation, poverty, poor health, and illiteracy in rural communities. This paper focuses, in particular, on road maintenance in some African countries considering types of road maintenance and the different approaches aiming at a comparison to reflect on similarities and differences.

  3. Rural general practice training: experience of a rural general practice team and a postgraduate year two registrar.

    Science.gov (United States)

    Scott-Jones, Joseph; Lucas, Sarah

    2013-09-01

    Undertaking training in rural areas is a recognised way of helping recruit staff to work in rural communities. Postgraduate year two medical doctors in New Zealand have been able to undertake a three-month placement in rural practice as part of their pre-vocational training experience since November 2010. To describe the experience of a rural general practice team providing training to a postgraduate year two medical trainee, and to describe the teaching experience and range of conditions seen by the trainee. A pre- and post-placement interview with staff, and analysis of a logbook of cases and teaching undertaken in the practice. The practice team's experience of having the trainee was positive, and the trainee was exposed to a wide range of conditions over 418 clinical encounters. The trainee received 22.5 hours of formal training over the three-month placement. Rural general practice can provide a wide range of clinical experience to a postgraduate year two medical trainee. Rural practices in New Zealand should be encouraged to offer teaching placements at this training level. Exposure to rural practice at every level of training is important to encourage doctors to consider rural practice as a career.

  4. A review of game-theoretic models of road user behaviour.

    Science.gov (United States)

    Elvik, Rune

    2014-01-01

    This paper reviews game-theoretic models that have been developed to explain road user behaviour in situations where road users interact with each other. The paper includes the following game-theoretic models: 1.A general model of the interaction between road users and their possible reaction to measures improving safety (behavioural adaptation).2.Choice of vehicle size as a Prisoners’ dilemma game.3.Speed choice as a co-ordination game.4.Speed compliance as a game between drivers and the police.5.Merging into traffic from an acceleration lane as a mixed-strategy game.6.Choice of level of attention in following situations as an evolutionary game.7.Choice of departure time to avoid congestion as variant of a Prisoners’ dilemma game.8.Interaction between cyclists crossing the road and car drivers.9.Dipping headlights at night well ahead of the point when glare becomes noticeable.10.Choice of evasive action in a situation when cars are on collision course. The models reviewed are different in many respects, but a common feature of the models is that they can explain how informal norms of behaviour can develop among road users and be sustained even if these informal norms violate the formal regulations of the traffic code. Game-theoretic models are not applicable to every conceivable interaction between road users or to situations in which road users choose behaviour without interacting with other road users. Nevertheless, it is likely that game-theoretic models can be applied more widely than they have been until now. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Vehicle operation characteristic under different ramp entrance conditions in underground road: Analysis, simulation and modelling

    Science.gov (United States)

    Yao, Qiming; Liu, Shuo; Liu, Yang

    2018-05-01

    An experimental design was used to study the vehicle operation characteristics of different ramp entrance conditions in underground road. With driving simulator, the experimental scenarios include left or right ramp with first, second and third service level, respectively, to collect vehicle speed, acceleration, lateral displacement and location information at the ramp entrance section. By using paired t-test and ANOVA, the influence factors of vehicle operating characteristics are studied. The result shows that effects of ramp layout and mainline traffic environment on vehicle operation characteristics are significant. The regression model of vehicle traveling distance on acceleration lane is established. Suggestions are made for ramp entrance design of underground road.

  6. Design and scope of impact of auxiliary lanes : technical report.

    Science.gov (United States)

    2014-06-01

    For decades, Texas Department of Transportation districts have constructed auxiliary lanes to support interchange : ramp operations and to resolve congestion proximate to freeway entrance and exit ramps. While auxiliary lanes are : built throughout T...

  7. Why are some animal populations unaffected or positively affected by roads?

    Science.gov (United States)

    Rytwinski, Trina; Fahrig, Lenore

    2013-11-01

    In reviews on effects of roads on animal population abundance we found that most effects are negative; however, there are also many neutral and positive responses [Fahrig and Rytwinski (Ecol Soc 14:21, 2009; Rytwinski and Fahrig (Biol Conserv 147:87-98, 2012)]. Here we use an individual-based simulation model to: (1) confirm predictions from the existing literature of the combinations of species traits and behavioural responses to roads that lead to negative effects of roads on animal population abundance, and (2) improve prediction of the combinations of species traits and behavioural responses to roads that lead to neutral and positive effects of roads on animal population abundance. Simulations represented a typical situation in which road mitigation is contemplated, i.e. rural landscapes containing a relatively low density (up to 1.86 km/km(2)) of high-traffic roads, with continuous habitat between the roads. In these landscapes, the simulations predict that populations of species with small territories and movement ranges, and high reproductive rates, i.e. many small mammals and birds, should not be reduced by roads. Contrary to previous suggestions, the results also predict that populations of species that obtain a resource from roads (e.g. vultures) do not increase with increasing road density. In addition, our simulations support the predation release hypothesis for positive road effects on prey (both small- and large-bodied prey), whereby abundance of a prey species increased with increasing road density due to reduced predation by generalist road-affected predators. The simulations also predict an optimal road density for the large-bodied prey species if it avoids roads or traffic emissions. Overall, the simulation results suggest that in rural landscapes containing high-traffic roads, there are many species for which road mitigation may not be necessary; mitigation efforts should be tailored to the species that show negative population responses to roads.

  8. Homotopy perturbation method with Laplace Transform (LT-HPM) for solving Lane-Emden type differential equations (LETDEs).

    Science.gov (United States)

    Tripathi, Rajnee; Mishra, Hradyesh Kumar

    2016-01-01

    In this communication, we describe the Homotopy Perturbation Method with Laplace Transform (LT-HPM), which is used to solve the Lane-Emden type differential equations. It's very difficult to solve numerically the Lane-Emden types of the differential equation. Here we implemented this method for two linear homogeneous, two linear nonhomogeneous, and four nonlinear homogeneous Lane-Emden type differential equations and use their appropriate comparisons with exact solutions. In the current study, some examples are better than other existing methods with their nearer results in the form of power series. The Laplace transform used to accelerate the convergence of power series and the results are shown in the tables and graphs which have good agreement with the other existing method in the literature. The results show that LT-HPM is very effective and easy to implement.

  9. Road accident fatality risks for "vulnerable" versus "protected" road users in northern Ghana.

    Science.gov (United States)

    Damsere-Derry, James; Palk, Gavan; King, Mark

    2017-10-03

    for the safety of VRUs in northern Ghana. Cycle paths and lanes (for cyclists) as well as sidewalks (for pedestrians) in particular will separate VRUs from motorists and improve their safety. Enforcement of traffic laws particularly regarding helmet use, speeding, and alcohol use will be beneficial. Introduction of the demerit points system in the enforcement of traffic regulations may have significant deterrent effects on road users who have the penchant for violating traffic regulations. Road safety education is also required to create responsible road users.

  10. “Bus Lane Within The Area Of Intersection” Method For Buses Priority On The Intersections

    Directory of Open Access Journals (Sweden)

    Vikovych Ihor

    2015-12-01

    Full Text Available The primary objective of this article is to formalize the “special bus lanes within the area of intersection” method that allows providing buses with space-time priority at signalized intersections (mostly of the isolated type, including those with no more than two traffic lanes in each direction at the approaches to the intersection. The article establishes the limits for efficient application of this method, and describes the results of a simulation experiment conducted in the VISSIM environment to investigate the functioning of the method on an actual intersection. The most critical phase of implementation of this method is to determine the optimum length of the special bus lane at the approach to the intersection. The optimum length of special bus lanes at the approaches to isolated or coordinated intersections is determined based on the maximum length of queued vehicles which is computed using the simulation models developed in the Objective-C language. The article covers the basic characteristics of those models, their structure and building principles, and also provides the model validation results. Simulation models can be used both for determination of the optimum length of special bus lanes at the approaches to signalized intersections and for analysis of intersection performance based on the maximum length of queued vehicles.

  11. How a fast lane may replace a congestion toll

    DEFF Research Database (Denmark)

    Fosgerau, Mogens

    2011-01-01

    This paper considers a congested bottleneck. A fast lane reserves a more than proportional share of capacity to a designated group of travellers. Travellers are otherwise identical and other travellers can use the reserved capacity when it would otherwise be idle. The paper shows that such a fast...... welfare improving when demand is elastic....... lane is always Pareto improving under Nash equilibrium in arrival times at the bottleneck and inelastic demand. It can replicate the arrival schedule and queueing outcomes of a toll that optimally charges a constant toll during part of the demand peak. Within some bounds, the fast lane scheme is still...

  12. How a fast lane may replace a congestion toll

    DEFF Research Database (Denmark)

    Fosgerau, Mogens

    This paper considers a congested bottleneck. A fast lane reserves a more than proportional share of capacity to a designated group of travellers. Travellers are otherwise identical and other travellers can use the reserved capacity when it would otherwise be idle. The paper shows that such a fast...... welfare improving when demand is elastic....... lane is always Pareto improving under Nash equilibrium in arrival times at the bottleneck and inelastic demand. It can replicate the arrival schedule and queueing outcomes of a toll that optimally charges a constant toll during part of the demand peak. Within some bounds, the fast lane scheme is still...

  13. Intelligent Lane Reservation System for Highway(s)

    OpenAIRE

    Dobre, Ciprian

    2012-01-01

    Highways tend to get congested because of the increase in the number of cars travelling on them. There are two solutions to this. The first one, which is also expensive, consists in building new highways to support the traffic. A much cheaper alternative consists in the introduction of advanced intelligent traffic control systems to manage traffic and increase the efficiency of the already existing highways. Intelligent lane reservation system for highways (ILRSH) is such a software control s...

  14. A case study on multi-lane roundabouts under congestion: Comparing software capacity and delay estimates with field data

    Directory of Open Access Journals (Sweden)

    Xuanwu Chen

    2016-04-01

    Full Text Available Existing studies on modern roundabouts performance are mostly based on data from singe lane roundabouts that are not heavily congested. For planners and designers interested in building multilane roundabouts for intersections with potential growth in future traffic, there has been a lack of existing studies with field data that provide reference values in terms of capacity and delay measurements. With the intent of providing such reference values, a case study was conducted by using the East Dowling Road Roundabouts in Anchorage, Alaska, which are currently operating with extensive queues during the evening peak hours. This research used multiple video camcorders to capture vehicle turning movements at the roundabouts as well as the progression of vehicle queues at the roundabout entrance approaches. With these video records, the number of vehicles in the queues can be accurately counted in any single minute during the peak hours. This study shows that unbalanced entrance flow patterns (i.e., one entrance has significant higher flow than others can intensify the queue and delay for the overall roundabouts. Then various software packages including RODEL, SIDRA and VISSIM were used to estimate several performance measurements, such as capacity, queue length, and delay, compared with the collected field data. With the comparison, it is found that all the three software packages overestimate multi-lane roundabout capacity before calibration. With default parameters, SIDRA and VISSIM tend to underestimate delays and queue lengths for the multi-lane roundabouts under congestion, while RODEL results in higher delay and queue length estimations at most of the entrance approaches.

  15. Rural general practice training: experience of a rural general practice team and a postgraduate year two registrar

    Directory of Open Access Journals (Sweden)

    Scott-Jones J

    2013-09-01

    Full Text Available INTRODUCTION: Undertaking training in rural areas is a recognised way of helping recruit staff to work in rural communities. Postgraduate year two medical doctors in New Zealand have been able to undertake a three-month placement in rural practice as part of their pre-vocational training experience since November 2010. AIM: To describe the experience of a rural general practice team providing training to a postgraduate year two medical trainee, and to describe the teaching experience and range of conditions seen by the trainee. METHODS: A pre- and post-placement interview with staff, and analysis of a logbook of cases and teaching undertaken in the practice. RESULTS: The practice team's experience of having the trainee was positive, and the trainee was exposed to a wide range of conditions over 418 clinical encounters. The trainee received 22.5 hours of formal training over the three-month placement. DISCUSSION: Rural general practice can provide a wide range of clinical experience to a postgraduate year two medical trainee. Rural practices in New Zealand should be encouraged to offer teaching placements at this training level. Exposure to rural practice at every level of training is important to encourage doctors to consider rural practice as a career.

  16. A mathematical model for predicting lane changes using the steering wheel angle.

    Science.gov (United States)

    Schmidt, Kim; Beggiato, Matthias; Hoffmann, Karl Heinz; Krems, Josef F

    2014-06-01

    Positive safety effects of advanced driver assistance systems can only become effective if drivers accept and use these systems. Early detection of driver's intention would allow for selective system activation and therefore reduce false alarms. This driving simulator study aims at exploring early predictors of lane changes. In total, 3111 lane changes of 51 participants on a simulated highway track were analyzed. Results show that drivers stopped their engagement in a secondary task about 7s before crossing the lane, which indicates a first planning phase of the maneuver. Subsequently, drivers start moving toward the lane, marking a mean steering wheel angle of 2.5°. Steering wheel angle as a directly measurable vehicle parameter appears as a promising early predictor of a lane change. A mathematical model of the steering wheel angle is presented, which is supposed to contribute for predicting lane change maneuvers. The mathematical model will be part of a further predictor of lane changes. This predictor can be a new advanced driver assistance system able to recognize a driver's intention. With this knowledge, other systems can be activated or deactivated so drivers get no annoying and exhausting alarm signals. This is one way how we can increase the acceptance of assistance systems. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Briefing paper : toward a best practice model for managed lanes in Texas.

    Science.gov (United States)

    2013-09-01

    Over the past two decades, agencies : have increasingly implemented managed : lanes (MLs) to mitigate growing urban traffic : congestion in the United States. Multiple operating : projects : representing a combination : of HOV-to-HOT conversions a...

  18. The Sight Distance Issues with Retrofitted Single-Lane HOV Facilities

    Directory of Open Access Journals (Sweden)

    Zhongren Wang

    2013-06-01

    Full Text Available It is well-known that obstruction inside a highway horizontal curve will lead to impaired sight distance. Highway alignment design standards in terms of the minimum horizontal curve radius are specified to allow for adequate stopping sight distance at given design speeds. For a single-lane HOV facility, inside curve obstruction may occur no matter when the facility curves to the left (per travel direction or right. A unique situation that calls for special attention is that the adjacent mixed-flow lane traffic, once queued, may become sight obstruction. Calculations indicated that such obstruction may govern the minimum curve radius design as long as the left shoulder is not less than 0.92 m, when the HOV lane is contiguous to the mixed-flow lanes. Such governance may necessitate design speed reduction, horizontal and cross-section design adjustment, or both.

  19. ON THE CURVATURE OF DUST LANES IN GALACTIC BARS

    International Nuclear Information System (INIS)

    Comeron, Sebastien; MartInez-Valpuesta, Inma; Knapen, Johan H.; Beckman, John E.

    2009-01-01

    We test the theoretical prediction that the straightest dust lanes in bars are found in strongly barred galaxies, or more specifically, that the degree of curvature of the dust lanes is inversely proportional to the strength of the bar. The test uses archival images of barred galaxies for which a reliable nonaxisymmetric torque parameter (Q b ) and the radius at which Q b has been measured (r(Q b )) have been published in the literature. Our results confirm the theoretical prediction but show a large spread that cannot be accounted for by measurement errors. We simulate 238 galaxies with different bar and bulge parameters in order to investigate the origin of the spread in the dust lane curvature versus Q b relation. From these simulations, we conclude that the spread is greatly reduced when describing the bar strength as a linear combination of the bar parameters Q b and the quotient of the major and minor axes of the bar, a/b. Thus, we conclude that the dust lane curvature is predominantly determined by the parameters of the bar.

  20. Deposition and solubility of airborne metals to four plant species grown at varying distances from two heavily trafficked roads in London

    International Nuclear Information System (INIS)

    Peachey, C.J.; Sinnett, D.; Wilkinson, M.; Morgan, G.W.; Freer-Smith, P.H.; Hutchings, T.R.

    2009-01-01

    In urban areas, a highly variable mixture of pollutants is deposited as particulate matter. The concentration and bioavailability of individual pollutants within particles need to be characterised to ascertain the risks to ecological receptors. This study, carried out at two urban parks, measured the deposition and water-solubility of metals to four species common to UK urban areas. Foliar Cd, Cr, Cu, Fe, Ni, Pb and Zn concentrations were elevated in at least one species compared with those from a rural control site. Concentrations were, however, only affected by distance to road in nettle and, to a lesser extent, birch leaves. Greater concentrations of metal were observed in these species compared to cypress and maple possibly due to differences in plant morphology and leaf surfaces. Solubility appeared to be linked to the size fraction and, therefore, origin of the metal with those present predominantly in the coarse fraction exhibiting low solubility. - High density traffic resulted in elevated metal concentrations on vegetation, which were related to distance from road and plant species.

  1. Deposition and solubility of airborne metals to four plant species grown at varying distances from two heavily trafficked roads in London

    Energy Technology Data Exchange (ETDEWEB)

    Peachey, C.J. [Forest Research, Centre for Forestry and Climate Change, Alice Holt Lodge, Farnham, Surrey GU10 4LH (United Kingdom); Sinnett, D., E-mail: danielle.sinnett@forestry.gsi.gov.u [Forest Research, Centre for Forestry and Climate Change, Alice Holt Lodge, Farnham, Surrey GU10 4LH (United Kingdom); Wilkinson, M., E-mail: matthew.wilkinson@forestry.gsi.gov.u [Forest Research, Centre for Forestry and Climate Change, Alice Holt Lodge, Farnham, Surrey GU10 4LH (United Kingdom); Morgan, G.W., E-mail: geoff.morgan@forestry.gsi.gov.u [Forest Research, Centre for Forestry and Climate Change, Alice Holt Lodge, Farnham, Surrey GU10 4LH (United Kingdom); Freer-Smith, P.H., E-mail: peter.freer-smith@forestry.gsi.gov.u [Forest Research, Centre for Forestry and Climate Change, Alice Holt Lodge, Farnham, Surrey GU10 4LH (United Kingdom); Hutchings, T.R., E-mail: tony.hutchings@forestry.gsi.gov.u [Forest Research, Centre for Forestry and Climate Change, Alice Holt Lodge, Farnham, Surrey GU10 4LH (United Kingdom)

    2009-08-15

    In urban areas, a highly variable mixture of pollutants is deposited as particulate matter. The concentration and bioavailability of individual pollutants within particles need to be characterised to ascertain the risks to ecological receptors. This study, carried out at two urban parks, measured the deposition and water-solubility of metals to four species common to UK urban areas. Foliar Cd, Cr, Cu, Fe, Ni, Pb and Zn concentrations were elevated in at least one species compared with those from a rural control site. Concentrations were, however, only affected by distance to road in nettle and, to a lesser extent, birch leaves. Greater concentrations of metal were observed in these species compared to cypress and maple possibly due to differences in plant morphology and leaf surfaces. Solubility appeared to be linked to the size fraction and, therefore, origin of the metal with those present predominantly in the coarse fraction exhibiting low solubility. - High density traffic resulted in elevated metal concentrations on vegetation, which were related to distance from road and plant species.

  2. Geo-Hazards and Mountain Road Development in Nepal: Understanding the Science-Policy-Governance Interface

    Science.gov (United States)

    Dugar, Sumit; Dahal, Vaskar

    2015-04-01

    The foothills of Nepalese Himalayas located in the neotectonic mountain environment are among some of the most unstable and geomorphologically dynamic landscapes in the world. Young fold mountains in this region are characterized by complex tectonics that influence the occurrence of earthquakes, while climatic processes such as intense orographic rainfall often dictate the occurrence of floods and landslides. Development of linear infrastructures, such as roads, in mountainous terrain characterized by high relief and orogeny is considerably challenging where the complexity of landscape in steep and irregular topography, difficult ground conditions and weak geology, presents engineers and planners with numerous difficulties to construct and maintain mountain roads. Whilst application of engineering geology, geomorphic interpretation of terrain in terms of physiography and hydrology, and identification of geo-hazards along the road corridor is critical for long term operation of mountain roads, low-cost arterial roads in the Himalayan foothills generally fail to incorporate standard road slope engineering structures. This research provides unique insights on policy and governance issues in developing mountainous countries such as Nepal, where achieving a sound balance between sustainability and affordability is a major challenge for road construction. Road development in Nepal is a complex issue where socio-economic and political factors influence the budget allocation for road construction in rural hilly areas. Moreover, most mountain roads are constructed without any geological or geo-technical site investigations due to rampant corruption and lack of adequate engineering supervision. Despite having good examples of rural road construction practices such as the Dharan-Dhankuta Road in Eastern Nepal where comprehensive terrain-evaluation methods and geo-technical surveys led to an improved understanding of road construction, learnings from this project have not

  3. Prevalence of driver physical factors leading to unintentional lane departure crashes.

    Science.gov (United States)

    Cicchino, Jessica B; Zuby, David S

    2017-07-04

    Some lane-keeping assist systems in development and production provide autonomous braking and steering to correct unintentional lane drift but otherwise require drivers to fully control their vehicles. The goal of this study was to quantify the proportion of drivers involved in unintentional lane drift crashes who would be unable to regain control of their vehicles to inform the design of such systems. The NHTSA's National Motor Vehicle Crash Causation Survey collected in-depth, on-scene data for a nationally representative sample of 5,470 U.S. police-reported passenger vehicle crashes during 2005-2007 that occurred between 6 a.m. and midnight and for which emergency medical services were dispatched. The physical states of drivers involved in the 631 lane drift crashes in the sample, which represented 259,034 crashes nationally, were characterized. Thirty-four percent of drivers who crashed because they drifted from their lanes were sleeping or otherwise incapacitated. These drivers would be unlikely to regain full control of their vehicles if an active safety system prevented their initial drift. An additional 13% of these drivers had a nonincapacitating medical issue, blood alcohol concentration (BAC) ≥ 0.08%, or other physical factor that may not allow them to regain full vehicle control. When crashes involved serious or fatal injuries, 42% of drivers who drifted were sleeping or otherwise incapacitated, and an additional 14% were impacted by a nonincapacitating medical issue, BAC ≥ 0.08%, or other physical factor. Designers of active safety systems that provide autonomous lateral control should consider that a substantial proportion of drivers at risk of lane drift crashes are incapacitated. Systems that provide only transient corrective action may not ultimately prevent lane departure crashes for these drivers, and drivers who do avoid lane drift crashes because of these systems may be at high risk of other types of crashes when they attempt to regain

  4. Agricultural vehicles and rural road safety: tackling a persistent problem.

    Science.gov (United States)

    Jaarsma, Catharinus F; De Vries, Jasper R

    2014-01-01

    Crashes involving agricultural vehicles (AVs) on public roads are an increasing road safety problem. We aim to analyze developments in the appearance and severity of these accidents, identify influencing factors, and draw lessons for possible interventions for accident prevention within the context of modern mechanized agriculture. To analyze developments in the appearance of accidents we use a subset of accidents with AVs involved on public roads in The Netherlands aggregated per year for 1987-2010. To identify and explore preventive measures we use an in-depth study of the Dutch Safety Board. With a study of international literature we put our findings in a wider context. During this time span, Dutch annual averages show 15 registered fatal accidents involving AVs, 93 with hospitalization and 137 with slight injuries. For nonfatal accidents, the numbers are decreasing over time. This decrease is proportionate to the reduction in the total number of traffic victims. For fatalities, however, the number is stable, increasing its proportion in all traffic fatalities from 1 in 1987 to 2 percent in 2010. Related to the number of inhabitants, this number is 2 times the value in the UK and 3 times the value in the United States. Influencing factors can be related to the 3 road system components (AV, driver, and infrastructure). Weak points for AVs are the view from the driver's seat, visibility at night, permitted vehicle width, and crash aggressivity (large kinetic energy of the AV) that is transferred to other road users in case of a collision. Important factors identified for the driver are poor risk perception and high risk acceptance, in combination with speeding, dysfunctional use such as the use of AVs as modes of transport to and from school, and driving on public roads without protecting or removing protruding and sharp components. For infrastructure, the focus is on road design and separation of AVs from other motor vehicles. Lessons to be learned follow from

  5. Motorcycle emissions and fuel consumption in urban and rural driving conditions.

    Science.gov (United States)

    Chen, K S; Wang, W C; Chen, H M; Lin, C F; Hsu, H C; Kao, J H; Hu, M T

    2003-08-01

    This work reports sampling of motorcycle on-road driving cycles in actual urban and rural environments and the development of representative driving cycles using the principle of least total variance in individual regions. Based on the representative driving cycles in individual regions, emission factors for carbon monoxide (CO), hydrocarbons (HC), nitrogen oxides (NO(x)=NO+NO(2)) and carbon dioxide (CO(2)), as well as fuel consumption, were determined using a chassis dynamometer. The measurement results show that the representative driving cycles are almost identical in the three largest cities in Taiwan, but they differ significantly from the rural driving cycle. Irrespective of driving conditions, emission factors differ insignificantly between the urban and rural regions at a 95% confidence level. However, the fuel consumption in urban centers is approximately 30% higher than in the rural regions, with driving conditions in the former usually poor compared to the latter. Two-stroke motorcycles generally have considerably higher HC emissions and quite lower NO(x) emissions than those of four-stroke motorcycles. Comparisons with other studies suggest that factors such as road characteristics, traffic volume, vehicle type, driving conditions and driver behavior may affect motorcycle emission levels in real traffic situations.

  6. Motorcycle emissions and fuel consumption in urban and rural driving conditions

    International Nuclear Information System (INIS)

    Chen, K.S.; Wang, W.C.; Chen, H.M.; Lin, C.F.; Hsu, H.C.; Kao, J.H.; Hu, M.T.

    2003-01-01

    This work reports sampling of motorcycle on-road driving cycles in actual urban and rural environments and the development of representative driving cycles using the principle of least total variance in individual regions. Based on the representative driving cycles in individual regions, emission factors for carbon monoxide (CO), hydrocarbons (HC), nitrogen oxides (NO x =NO+NO 2 ) and carbon dioxide (CO 2 ), as well as fuel consumption, were determined using a chassis dynamometer. The measurement results show that the representative driving cycles are almost identical in the three largest cities in Taiwan, but they differ significantly from the rural driving cycle. Irrespective of driving conditions, emission factors differ insignificantly between the urban and rural regions at a 95% confidence level. However, the fuel consumption in urban centers is approximately 30% higher than in the rural regions, with driving conditions in the former usually poor compared to the latter. Two-stroke motorcycles generally have considerably higher HC emissions and quite lower NO x emissions than those of four-stroke motorcycles. Comparisons with other studies suggest that factors such as road characteristics, traffic volume, vehicle type, driving conditions and driver behavior may affect motorcycle emission levels in real traffic situations

  7. A Review of Adverse Effects of Road Traffic Noise on Human Health

    Science.gov (United States)

    Singh, Devi; Kumari, Neeraj; Sharma, Pooja

    Noise pollution due to road traffic is a potential threat to human health. Since it is a global hazard, the rapid urbanization and exponential traffic growth have aggravated the problem. Population residing along the busy traffic lanes is continuously exposed to the sound levels which are above the permissible limits. This constant exposure to noise pollution is a cause of concern as it leads to several adverse impacts on human health. Traffic noise causes irritation and annoyance, sleep disturbances, cardiovascular disease, risk of stroke, diabetes, hypertension and loss of hearing. It results in decreased work performance. The present review highlights the serious health hazards of road traffic noise (RTN) which needs to be curbed. Preventive measures of noise pollution can help in combating noise-induced health hazards and increased work performance.

  8. Fast food purchasing and access to fast food restaurants: a multilevel analysis of VicLANES

    Science.gov (United States)

    Thornton, Lukar E; Bentley, Rebecca J; Kavanagh, Anne M

    2009-01-01

    Background While previous research on fast food access and purchasing has not found evidence of an association, these studies have had methodological problems including aggregation error, lack of specificity between the exposures and outcomes, and lack of adjustment for potential confounding. In this paper we attempt to address these methodological problems using data from the Victorian Lifestyle and Neighbourhood Environments Study (VicLANES) – a cross-sectional multilevel study conducted within metropolitan Melbourne, Australia in 2003. Methods The VicLANES data used in this analysis included 2547 participants from 49 census collector districts in metropolitan Melbourne, Australia. The outcome of interest was the total frequency of fast food purchased for consumption at home within the previous month (never, monthly and weekly) from five major fast food chains (Red Rooster, McDonalds, Kentucky Fried Chicken, Hungry Jacks and Pizza Hut). Three measures of fast food access were created: density and variety, defined as the number of fast food restaurants and the number of different fast food chains within 3 kilometres of road network distance respectively, and proximity defined as the road network distance to the closest fast food restaurant. Multilevel multinomial models were used to estimate the associations between fast food restaurant access and purchasing with never purchased as the reference category. Models were adjusted for confounders including determinants of demand (attitudes and tastes that influence food purchasing decisions) as well as individual and area socio-economic characteristics. Results Purchasing fast food on a monthly basis was related to the variety of fast food restaurants (odds ratio 1.13; 95% confidence interval 1.02 – 1.25) after adjusting for individual and area characteristics. Density and proximity were not found to be significant predictors of fast food purchasing after adjustment for individual socio-economic predictors

  9. Fast food purchasing and access to fast food restaurants: a multilevel analysis of VicLANES.

    Science.gov (United States)

    Thornton, Lukar E; Bentley, Rebecca J; Kavanagh, Anne M

    2009-05-27

    While previous research on fast food access and purchasing has not found evidence of an association, these studies have had methodological problems including aggregation error, lack of specificity between the exposures and outcomes, and lack of adjustment for potential confounding. In this paper we attempt to address these methodological problems using data from the Victorian Lifestyle and Neighbourhood Environments Study (VicLANES) - a cross-sectional multilevel study conducted within metropolitan Melbourne, Australia in 2003. The VicLANES data used in this analysis included 2547 participants from 49 census collector districts in metropolitan Melbourne, Australia. The outcome of interest was the total frequency of fast food purchased for consumption at home within the previous month (never, monthly and weekly) from five major fast food chains (Red Rooster, McDonalds, Kentucky Fried Chicken, Hungry Jacks and Pizza Hut). Three measures of fast food access were created: density and variety, defined as the number of fast food restaurants and the number of different fast food chains within 3 kilometres of road network distance respectively, and proximity defined as the road network distance to the closest fast food restaurant.Multilevel multinomial models were used to estimate the associations between fast food restaurant access and purchasing with never purchased as the reference category. Models were adjusted for confounders including determinants of demand (attitudes and tastes that influence food purchasing decisions) as well as individual and area socio-economic characteristics. Purchasing fast food on a monthly basis was related to the variety of fast food restaurants (odds ratio 1.13; 95% confidence interval 1.02 - 1.25) after adjusting for individual and area characteristics. Density and proximity were not found to be significant predictors of fast food purchasing after adjustment for individual socio-economic predictors. Although we found an independent

  10. Fast food purchasing and access to fast food restaurants: a multilevel analysis of VicLANES

    Directory of Open Access Journals (Sweden)

    Kavanagh Anne M

    2009-05-01

    Full Text Available Abstract Background While previous research on fast food access and purchasing has not found evidence of an association, these studies have had methodological problems including aggregation error, lack of specificity between the exposures and outcomes, and lack of adjustment for potential confounding. In this paper we attempt to address these methodological problems using data from the Victorian Lifestyle and Neighbourhood Environments Study (VicLANES – a cross-sectional multilevel study conducted within metropolitan Melbourne, Australia in 2003. Methods The VicLANES data used in this analysis included 2547 participants from 49 census collector districts in metropolitan Melbourne, Australia. The outcome of interest was the total frequency of fast food purchased for consumption at home within the previous month (never, monthly and weekly from five major fast food chains (Red Rooster, McDonalds, Kentucky Fried Chicken, Hungry Jacks and Pizza Hut. Three measures of fast food access were created: density and variety, defined as the number of fast food restaurants and the number of different fast food chains within 3 kilometres of road network distance respectively, and proximity defined as the road network distance to the closest fast food restaurant. Multilevel multinomial models were used to estimate the associations between fast food restaurant access and purchasing with never purchased as the reference category. Models were adjusted for confounders including determinants of demand (attitudes and tastes that influence food purchasing decisions as well as individual and area socio-economic characteristics. Results Purchasing fast food on a monthly basis was related to the variety of fast food restaurants (odds ratio 1.13; 95% confidence interval 1.02 – 1.25 after adjusting for individual and area characteristics. Density and proximity were not found to be significant predictors of fast food purchasing after adjustment for individual socio

  11. Study on Hot Gases Flow in Case of Fire in a Road Tunnel

    Directory of Open Access Journals (Sweden)

    Aleksander Król

    2018-03-01

    Full Text Available This paper presents the results of hot smoke tests, which were conducted in a real road tunnel. The tunnel is located within the expressway S69 in southern Poland between cities Żywiec and Zwardoń. Its common name is Laliki tunnel. It is a bidirectional non-urban tunnel. The length of the tunnel is 678 m and it is inclined by 4%. It is equipped with the longitudinal ventilation system. Two hot smoke tests have been carried out according to Australian Standard AS 4391-1999. Hot smoke tests corresponded to a Heat Release Rate (HRR equal to respectively 750 kW and 1500 kW. The fire source was located in the middle of the road lane imitating an initial phase of a car fire (respectively 150 m and 265 m from S portal. The temperature distribution was recorded during both tests using a set of fourteen thermocouples that were mounted at two stand poles located at the main axis of the tunnel on windward. The stand poles were placed at distances of 5 m and 10 m. The recorded data were applied to validate a numerical model, which was built and solved using Ansys Fluent. The calculated temperature distribution matched the measured values.

  12. Determination of road dust loadings and chemical characteristics using resuspension.

    Science.gov (United States)

    Chen, Jianhua; Wang, Wei; Liu, Hongjie; Ren, Lihong

    2012-03-01

    The contribution of fugitive dust from traffic to air pollution can no longer be ignored in China. In order to obtain the road dust loadings and to understand the chemical characteristics of PM(10) and PM(2.5) from typical road dust, different paved roads in eight districts of Beijing were selected for dust collection during the four seasons of 2005. Ninety-eight samples from 28 roads were obtained. The samples were resuspended using equipment assembled to simulate the rising process of road dust caused by the wind or wheels in order to obtain the PM(10) and PM(2.5) filter samples. The average road dust loading was 3.82 g m(-2), with the highest of 24.22 g m(-2) being in Hutongs in the rural-urban continuum during winter. The road dust loadings on higher-grade roads were lower than those on lower-grade roads. Attention should be paid to the pollution in the rural-urban continuum areas. The sums of element abundances measured were 16.17% and 18.50% for PM(10) and PM(2.5) in road dust. The average abundances of OC and EC in PM(10) and PM(2.5) in road dust were 11.52%, 2.01% and 12.50%, 2.06%, respectively. The abundance of elements, water-soluble ions, and OC, EC in PM(10) and PM(2.5) resuspended from road dust did not change greatly with seasons and road types. The soil dust, construction dust, dust emitted from burning coal, vehicle exhaust, and deposition of particles in the air were the main sources of road dust in Beijing. Affected by the application of snow-melting agents in Beijing during winter, the amount of Cl( - ) and Na( + ) was much higher during that time than in the other seasons. This will have a certain influence on roads, bridges, vegetations, and groundwater.

  13. Rural Tourism - Alternative to the Development of Rural Areas

    Directory of Open Access Journals (Sweden)

    Maria Cristina PAIU

    2017-06-01

    Full Text Available Rural tourism through its content and its features is a distinct component in the economy of a region, and the sustainable, efficient use of local tourism resources can be an extremely important activity by: adding added value, boosting productivity, employment and increasing the living standard of the population. Rural tourism is considered a lever to mitigate local imbalances and besides attracting touristic areas in the circuit, it also has consequences on territorial development: housing construction, road development, development of public services and the development of small and medium-sized enterprises. Consequently, rural tourism has an impact on a country's economic and social development strategy, but also on a branch level.

  14. Design of a lane departure driver-assist system under safety specifications

    OpenAIRE

    Hoehener Daniel; Huang Geng; Del Vecchio Domitilla

    2016-01-01

    We use a controlled invariance approach to design a semi-autonomous lane departure assist system that is guaranteed to keep the vehicle in the lane. The controlled invariant safe set is the set of system states from which an input exists that can keep the vehicle in the lane. First we provide theoretical conditions under which this set has a simple characterization and can be computed in real-time. We then use this characterization to derive a feedback strategy that keeps the vehicle in the l...

  15. IMPACT OF ROAD TRANSPORT ON AGRICULTURAL ...

    African Journals Online (AJOL)

    Osondu

    2012-03-09

    Mar 9, 2012 ... major means of transporting agricultural produce from the farms to the markets as well as to ... methods were both employed to analyze the data gathered. ... Keywords: Rural Development, Marketing, Transportation, Agricultural Production & Road. Network ... traffic over short, medium and long distances.

  16. Housing Density and Ecosystem Function: Comparing the Impacts of Rural, Exurban, and Suburban Densities on Fire Hazard, Water Availability, and House and Road Distance Effects

    Directory of Open Access Journals (Sweden)

    Jelena Vukomanovic

    2013-11-01

    Full Text Available Many amenity-rich regions are experiencing rapid land-use change through low-density residential development or exurbanization. Those same natural-resource amenities that attracted migration are often degraded by housing growth and associated development. This study examines the impacts of exurbanization on three ecosystem indicators (fire hazard, water availability, and generalized distance effects of houses and roads and compares them to areas with rural and suburban housing densities in the Sonoita Plain, southeastern Arizona. We found that although they support significantly lower population densities, exurban areas have impacts on ecosystem function comparable to suburban areas. Exurban areas had the highest potential for fire, suggesting that it is the presence of people rather than the density that increases fire hazard. The increase in the number of wells in exurban areas far exceeded suburban areas and matched increases for agricultural use in rural areas. When the impacts of houses and roads on ecosystem function were considered, 98% of exurban areas were “highly” or “very highly” impacted, compared to 100% for suburban areas and 35% for rural areas. Since development in the area is not readily visible, assessing the spatial extent of impacts is important for understanding the vulnerability of systems and guiding decisions about development.

  17. Thermographic survey of two rural buildings in Spain

    Energy Technology Data Exchange (ETDEWEB)

    Martin Ocana, S.; Canas Guerrero, I. [Departamento de Construccion y Vias Rurales, Escuela Tecnica Superior de Ingenieros Agronomos, Universidad Politecnica de Madrid, Madrid (Spain); Gonzalez Requena, I. [Departamento de Materiales y Produccion Aeroespacial, Escuela Tecnica Superior de Ingenieros Aeronauticos, Universidad Politecnica de Madrid, Madrid (Spain)

    2004-07-01

    Two common housing prototypes of existing buildings in Spanish rural areas were surveyed by infrared inspection. The aim of the study is to assess the usefulness of infrared thermography as a technique for the detection of the thermal performance of rural buildings. For the traditional house the best results were obtained in the thermographic survey carried out in the evening. Contrarily, for the modern house the thermographic survey at daybreak provided more information. Infrared thermography allowed the comparison of the thermal performance of two buildings. (author)

  18. A Precise Lane Detection Algorithm Based on Top View Image Transformation and Least-Square Approaches

    Directory of Open Access Journals (Sweden)

    Byambaa Dorj

    2016-01-01

    Full Text Available The next promising key issue of the automobile development is a self-driving technique. One of the challenges for intelligent self-driving includes a lane-detecting and lane-keeping capability for advanced driver assistance systems. This paper introduces an efficient and lane detection method designed based on top view image transformation that converts an image from a front view to a top view space. After the top view image transformation, a Hough transformation technique is integrated by using a parabolic model of a curved lane in order to estimate a parametric model of the lane in the top view space. The parameters of the parabolic model are estimated by utilizing a least-square approach. The experimental results show that the newly proposed lane detection method with the top view transformation is very effective in estimating a sharp and curved lane leading to a precise self-driving capability.

  19. A Qualitative Study of Environmental Factors Important for Physical Activity in Rural Adults.

    Science.gov (United States)

    Cleland, Verity; Hughes, Clarissa; Thornton, Lukar; Venn, Alison; Squibb, Kathryn; Ball, Kylie

    2015-01-01

    Despite increasing evidence that the physical environment impacts on physical activity among urban-dwellers, little attention has been devoted to understanding this relationship in rural populations. Work in this area is further hindered by a lack of environmental measures specifically designed for rural settings. This qualitative study aimed to explore the salience of urban physical activity environment constructs among rural adults. In 2011, 49 rural men and women from three distinct areas (coastal, animal-based farming, forestry/plant-based farming) of rural Tasmania, Australia, were purposively recruited to participate in semi-structured interviews. Interviews explored features of the built and social environment commonly examined in studies of urban adults, including functional characteristics (eg, lighting, footpaths, roads/verges), road and personal safety, availability and accessibility of places to be active, destinations, and aesthetics. Interviews were recorded, transcribed verbatim and analysed using a content-thematic approach using QSR NVivo software. While some urban environmental constructs were salient to these rural adults, such as availability of and accessibility to places to be active, some constructs were operationalised differently, such as road safety (where large trucks and winding roads rather than traffic density was of concern), or were not considered relevant (eg, personal safety related to crime, availability of walkable destinations, aesthetics). The measurement of the physical environment in rural populations may require reconsideration and/or modification to ensure salience and appropriate quantification of associations with physical activity in future studies.

  20. A Qualitative Study of Environmental Factors Important for Physical Activity in Rural Adults.

    Directory of Open Access Journals (Sweden)

    Verity Cleland

    Full Text Available Despite increasing evidence that the physical environment impacts on physical activity among urban-dwellers, little attention has been devoted to understanding this relationship in rural populations. Work in this area is further hindered by a lack of environmental measures specifically designed for rural settings. This qualitative study aimed to explore the salience of urban physical activity environment constructs among rural adults.In 2011, 49 rural men and women from three distinct areas (coastal, animal-based farming, forestry/plant-based farming of rural Tasmania, Australia, were purposively recruited to participate in semi-structured interviews. Interviews explored features of the built and social environment commonly examined in studies of urban adults, including functional characteristics (eg, lighting, footpaths, roads/verges, road and personal safety, availability and accessibility of places to be active, destinations, and aesthetics. Interviews were recorded, transcribed verbatim and analysed using a content-thematic approach using QSR NVivo software.While some urban environmental constructs were salient to these rural adults, such as availability of and accessibility to places to be active, some constructs were operationalised differently, such as road safety (where large trucks and winding roads rather than traffic density was of concern, or were not considered relevant (eg, personal safety related to crime, availability of walkable destinations, aesthetics.The measurement of the physical environment in rural populations may require reconsideration and/or modification to ensure salience and appropriate quantification of associations with physical activity in future studies.

  1. Extracting Lane Geometry and Topology Information from Vehicle Fleet Trajectories in Complex Urban Scenarios Using a Reversible Jump Mcmc Method

    Science.gov (United States)

    Roeth, O.; Zaum, D.; Brenner, C.

    2017-05-01

    Highly automated driving (HAD) requires maps not only of high spatial precision but also of yet unprecedented actuality. Traditionally small highly specialized fleets of measurement vehicles are used to generate such maps. Nevertheless, for achieving city-wide or even nation-wide coverage, automated map update mechanisms based on very large vehicle fleet data gain importance since highly frequent measurements are only to be obtained using such an approach. Furthermore, the processing of imprecise mass data in contrast to few dedicated highly accurate measurements calls for a high degree of automation. We present a method for the generation of lane-accurate road network maps from vehicle trajectory data (GPS or better). Our approach therefore allows for exploiting today's connected vehicle fleets for the generation of HAD maps. The presented algorithm is based on elementary building blocks which guarantees useful lane models and uses a Reversible Jump Markov chain Monte Carlo method to explore the models parameters in order to reconstruct the one most likely emitting the input data. The approach is applied to a challenging urban real-world scenario of different trajectory accuracy levels and is evaluated against a LIDAR-based ground truth map.

  2. Rural Brazil at the cross-roads

    NARCIS (Netherlands)

    Meijer, H.

    1951-01-01

    The study attempts to detect and discuss the most urgently needed changes, as to resource distribution, production methods and supporting services in Brazilian agriculture. For that, it was necessary to describe and evaluate the existing situation in rural Brazil, a task taken up in the first part

  3. Safer Roads: Comparisons Between Road Assessment Program and Composite Road Safety Index Method

    Directory of Open Access Journals (Sweden)

    Mohd Razelan Intan Suhana

    2017-01-01

    Full Text Available In most countries, crash statistics have becoming very crucial in evaluating road’s safety level. In Malaysia, these data are very important in deciding crash-prone areas known as black spot where specific road improvements plan will be proposed. However due to the unavailability of reliable crash data in many developing countries, appropriate road maintenance measures are facing great troubles. In light of that, several proactive methods in defining road’s safety level such as Road Assessment Program (RAP have emerged. This research aim to compare two proactive methods that have been tested in Malaysian roads ; road assessment program and road environment risk index which was developed based on composite index theory in defining road’s safety level. Composite road environment risk index was combining several crucial environment indicators, assigning weight and aggregating the individual index together to form a single value representing the road’s safety level. Based on the results, it can be concluded that both road assessment program and composite road environment risk index are contradicted in six different ways such as type of speed used, type of analysis used and their final outcomes. However, with an aim to promote safer roads, these two methods can be used concurrently as the outcomes in both methods seems to fulfil each other’s gap very well.

  4. On-road driving impairments and associated cognitive deficits after stroke.

    Science.gov (United States)

    Devos, Hannes; Tant, Mark; Akinwuntan, Abiodun E

    2014-01-01

    Little is known about the critical on-road driving skills that get affected after a stroke. The purpose of this study was to investigate the key on-road driving impairments and their associated cognitive deficits after a stroke. A second aim was to investigate if lateralization of stroke impacts results of the cognitive and on-road driving tests. In this cross-sectional study, 99 participants with a first-ever stroke who were actively driving prior to stroke underwent a cognitive battery and a standardized road test that evaluated 13 specific on-road driving skills. These on-road driving skills were mapped onto an existing, theoretical framework that categorized the on-road items into hierarchic clusters of operational, tactical, visuo-integrative, and mixed driving skills. The total score on the road test and the on-road decision, made by a certified fitness-to-drive expert, decided the main outcome. The critical on-road driving skills predicting the on-road decision were identified using logistic regression analysis. Linear regression analysis was employed to determine the cognitive impairments leading to poor total on-road scores. Analyses were repeated for right- and left-sided strokes. In all, 37 persons scored poorly on the road test. These participants performed worse in all hierarchic clusters of on-road driving. Performances on the operational cluster and the visuo-integrative cluster best predicted on-road decisions (R(2) = 0.60). 'Lane changing' and 'understanding, insight, and quality of traffic participation' were the critical skill deficits leading to poor performance on the road test (R(2) = 0.65). Divided attention was the main determinant of on-road scores in the total group (R(2) = 0.06). Participants with right-sided stroke performed worse on visual field, visual neglect, visual scanning, visuo-constructive skills, and divided attention compared with those with left-sided stroke. Divided attention was the main determinant of total on-road scores

  5. Street Lighting Infrastructure Assessment Using Discriminant and GIS Method on Mount Merapi Evacuation Road

    Science.gov (United States)

    Izdihar, R. P.; Maryono, M.; Widjonarko, W.; Rahayu, S.

    2018-02-01

    This research aims to assess street lighting infrastructure in rural-urban of Mount Merapi Evacuation road. Three evacuation road/corridor; Mriyan-Boyolali, Wonodoyo-Boyolali and Samiran-Boyolali are selected as case study. By using discriminant this study examine 6 variables namely type of lamp, physical component, height, time, power and cons consumption. In addition this study also using GIS method to assessing geographical feature as of previous result. According to the discriminant analysis, the characteristic of street lighting could be distinguished as two characteristic, while from the GIS assessment, the study found three characteristic of geographical street lighting feature.

  6. Characteristic Analysis of Mixed Traffic Flow of Regular and Autonomous Vehicles Using Cellular Automata

    Directory of Open Access Journals (Sweden)

    Yangzexi Liu

    2017-01-01

    Full Text Available The technology of autonomous vehicles is expected to revolutionize the operation of road transport systems. The penetration rate of autonomous vehicles will be low at the early stage of their deployment. It is a challenge to explore the effects of autonomous vehicles and their penetration on heterogeneous traffic flow dynamics. This paper aims to investigate this issue. An improved cellular automaton was employed as the modeling platform for our study. In particular, two sets of rules for lane changing were designed to address mild and aggressive lane changing behavior. With extensive simulation studies, we obtained some promising results. First, the introduction of autonomous vehicles to road traffic could considerably improve traffic flow, particularly the road capacity and free-flow speed. And the level of improvement increases with the penetration rate. Second, the lane-changing frequency between neighboring lanes evolves with traffic density along a fundamental-diagram-like curve. Third, the impacts of autonomous vehicles on the collective traffic flow characteristics are mainly related to their smart maneuvers in lane changing and car following, and it seems that the car-following impact is more pronounced.

  7. Effects of 4WD and ABS of safe driving on slippery roads; Tei {mu} ji ni okeru 4WD to ABS no koka to unten sosa hoho

    Energy Technology Data Exchange (ETDEWEB)

    Kojima, Y [National Research Inst. of Police Science, Tokyo (Japan); Takigami, K; Asano, K [Japan Safe Driving Center, Tokyo (Japan); Nagai, M [Tokyo University of Agriculture and Technology, Tokyo (Japan)

    1997-10-01

    Effects of 4WD and ABS on safe driving were examined by brake, obstacle avoidance, acceleration, cornering and lane-changing tests on slippery road. The braking operations, used in these tests, are full, intermitted and modulated brakings. As the results of discussion, the major findings are (1) ABS is effective to shorten the stopping distance and to increase the ability of obstacle avoidance in many cases, (2) `Modulated Braking (without wheel locks)` has the same function as ABS, and (3) 4WD is effective to increase the stability while accelerating, cornering and lane-changing. 5 refs., 6 figs.

  8. Definition of run-off-road crash clusters-For safety benefit estimation and driver assistance development.

    Science.gov (United States)

    Nilsson, Daniel; Lindman, Magdalena; Victor, Trent; Dozza, Marco

    2018-04-01

    Single-vehicle run-off-road crashes are a major traffic safety concern, as they are associated with a high proportion of fatal outcomes. In addressing run-off-road crashes, the development and evaluation of advanced driver assistance systems requires test scenarios that are representative of the variability found in real-world crashes. We apply hierarchical agglomerative cluster analysis to define similarities in a set of crash data variables, these clusters can then be used as the basis in test scenario development. Out of 13 clusters, nine test scenarios are derived, corresponding to crashes characterised by: drivers drifting off the road in daytime and night-time, high speed departures, high-angle departures on narrow roads, highways, snowy roads, loss-of-control on wet roadways, sharp curves, and high speeds on roads with severe road surface conditions. In addition, each cluster was analysed with respect to crash variables related to the crash cause and reason for the unintended lane departure. The study shows that cluster analysis of representative data provides a statistically based method to identify relevant properties for run-off-road test scenarios. This was done to support development of vehicle-based run-off-road countermeasures and driver behaviour models used in virtual testing. Future studies should use driver behaviour from naturalistic driving data to further define how test-scenarios and behavioural causation mechanisms should be included. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. A FAST AND ROBUST ALGORITHM FOR ROAD EDGES EXTRACTION FROM LIDAR DATA

    Directory of Open Access Journals (Sweden)

    K. Qiu

    2016-06-01

    Full Text Available Fast mapping of roads plays an important role in many geospatial applications, such as infrastructure planning, traffic monitoring, and driver assistance. How to extract various road edges fast and robustly is a challenging task. In this paper, we present a fast and robust algorithm for the automatic road edges extraction from terrestrial mobile LiDAR data. The algorithm is based on a key observation: most roads around edges have difference in elevation and road edges with pavement are seen in two different planes. In our algorithm, we firstly extract a rough plane based on RANSAC algorithm, and then multiple refined planes which only contains pavement are extracted from the rough plane. The road edges are extracted based on these refined planes. In practice, there is a serious problem that the rough and refined planes usually extracted badly due to rough roads and different density of point cloud. To eliminate the influence of rough roads, the technology which is similar with the difference of DSM (digital surface model and DTM (digital terrain model is used, and we also propose a method which adjust the point clouds to a similar density to eliminate the influence of different density. Experiments show the validities of the proposed method with multiple datasets (e.g. urban road, highway, and some rural road. We use the same parameters through the experiments and our algorithm can achieve real-time processing speeds.

  10. An Abstract Model for Proving Safety of Multi-lane Traffic Manoeuvres

    DEFF Research Database (Denmark)

    Hilscher, Martin; Linker, Sven; Olderog, Ernst-Rüdiger

    2011-01-01

    on the view of each car. To guarantee safety, we present two variants of a lane-change controller, one with perfect knowledge of the safety envelopes of neighbouring cars and one which takes only the size of the neighbouring cars into account. Based on these controllers we provide a local safety proof...

  11. Effect of the Road Environment on Road Safety in Poland

    Science.gov (United States)

    Budzynski, Marcin; Jamroz, Kazimierz; Antoniuk, Marcin

    2017-10-01

    Run-off-road accidents tend to be very severe because when a vehicle leaves the road, it will often crash into a solid obstacle (tree, pole, supports, front wall of a culvert, barrier). A statistical analysis of the data shows that Poland’s main roadside hazard is trees and the severity of vehicles striking a tree in a run-off-road crash. The risks are particularly high in north-west Poland with many of the roads lined up with trees. Because of the existing rural road cross-sections, i.e. having trees directly on road edge followed immediately by drainage ditches, vulnerable road users are prevented from using shoulders and made to use the roadway. With no legal definition of the road safety zone in Polish regulations, attempts to remove roadside trees lead to major conflicts with environmental stakeholders. This is why a compromise should be sought between the safety of road users and protection of the natural environment and the aesthetics of the road experience. Rather than just cut the trees, other road safety measures should be used where possible to treat the hazardous spots by securing trees and obstacles and through speed management. Accidents that are directly related to the road environment fall into the following categories: hitting a tree, hitting a barrier, hitting a utility pole or sign, vehicle rollover on the shoulder, vehicle rollover on slopes or in ditch. The main consequence of a roadside hazard is not the likelihood of an accident itself but of its severity. Poland’s roadside accident severity is primarily the result of poor design or operation of road infrastructure. This comes as a consequence of a lack of regulations or poorly defined regulations and failure to comply with road safety standards. The new analytical model was designed as a combination of the different factors and one that will serve as a comprehensive model. It was assumed that it will describe the effect of the roadside on the number of accidents and their consequences

  12. Addressing Road Infrastructural Needs of Rural Communities for ...

    African Journals Online (AJOL)

    Journal of Agriculture and Social Research (JASR) ... In addition to extensive review of official document of Abia State governments, structured ... and recommends strategic measures for improving the road network and promoting social and ...

  13. In-transit charging lane model

    NARCIS (Netherlands)

    Verkerk, A.; Nijmeijer, H.; Khajepour, A.

    2012-01-01

    The current electric vehicles still have a problem with a short range and long charging time compared to the internal combustion vehicles. A possible solution for this problem is to charge the batteries while driving on the highway. For this, a special traffic lane is needed with an in-transit

  14. [Road safety in Italy: epidemiology of two-wheeled motor vehicles accidents. National statistics 2000].

    Science.gov (United States)

    Morandi, Anna; Berzolari, Francesca Gigli; Marinoni, Alessandra

    2004-01-01

    to describe road accidents occurred in Italy focusing, in particular, on two-wheeled motor vehicles. Analysis of road accidents based on current data referring to year 2000. Italy. In Italy, 67,127 two-wheeled motor vehicle accidents occurred in 2000. Two crash types account for 75% of the accidents: side impact and front-side impact. Per one million kilometres travelled 0.4 cars and 1.3 two-wheeled vehicles are involved (0.7 motorcycles and 2.2 mopeds). In 2000 there were 1,229 deaths and 69,543 injured riders. Males up to forty years old are the most represented. The masculinity ratio presents a decreasing trend from motorcycles to mopeds and to cars both for killed people and for injured people. The lethality rate increases with age for all types of vehicles but for mopeds this trend is much more evident. Most of the accident occur in urban road while most of the deaths happen in extra-urban road. Mopeds and motorcycles, which are a small subset of all motor vehicles (approximately 20%), are greatly overrepresented in crashes. Considering the kilometres travelled, the risk to be involved in a crash for mopeds is estimated to be 32.6 times higher than the comparable risk for cars and for motorcycles it is 17 times higher. The risk of death for riders is two times the risk for cars.

  15. Evaluation of safety ratings of roads based on frontal crashes with known crash pulse and injury outcome.

    Science.gov (United States)

    Stigson, H

    2009-06-01

    The objective in this study, using data from crashed cars fitted with on-board crash pulse recorders, was to present differences in average crash severity, distribution of crash severity, and injury outcomes, based on an independent safety rating of roads, also taking road type and speed limit into consideration. Furthermore, the objective was to evaluate differences in injury risk, based on the distribution of crash severity. The investigation included both frontal two-vehicle crashes and single-vehicle crashes with known injury outcome. In total, 209 real-world crashes involving cars fitted with crash pulse recorders were included. For all crashes, average mean acceleration and change of velocity of the vehicle acceleration pulse were measured and calculated. All crash spots were classified according to an independent road safety rating program (European Road Assessment Programme Road Protection Score), where the safety quality of roads is rated in relation to posted speed limits. The crash severity and injury outcome in crashes that occurred on roads with good safety ratings were compared with crashes on roads with poor safety ratings. The data were also divided into subcategories according to posted speed limit and road type, to evaluate whether there was a difference in crash severity and injury outcome within the categories. In total, crash severity was statistically significantly lower in crashes occurring on roads with good safety ratings than in crashes occurring on roads with poor safety ratings. It was found that crash severity and injury risk were lower on roads with good safety ratings with a speed limit of above 90 km/h compared with roads with poor safety ratings, irrespective of speed limit. On the other hand, crash severity was higher on roads with good safety ratings with speed limit of 70 km/h than on roads with poor safety ratings with the same speed limit. Though it was found that a higher speed limit resulted in higher crash severity on roads

  16. Design-Build-Finance in the US: The case of iROX, I-75 Road Expansion Project

    OpenAIRE

    Forcael,E; Ellis, JR,R; Jaramillo,F

    2011-01-01

    This project is part of the Interstate 75 road expansion, located in Southwest Florida and consisted of an expansion from four to six lanes along a 30-mile stretch. The paper presents a design, build and finance (DBF) approach applied to a US highway. This work focuses on the financial structure of the project, which did not include a concession (operation); the bidding procedure, which took into account an interesting bid evaluation criterion and; project management matters. The information ...

  17. Characterizing information propagation through inter-vehicle communication on a simple network of two parallel roads

    Science.gov (United States)

    2010-10-01

    In this report, we study information propagation via inter-vehicle communication along two parallel : roads. By identifying an inherent Bernoulli process, we are able to derive the mean and variance of : propagation distance. A road separation distan...

  18. Model simulation of Venezia-Mestre ring road air pollution: experimental check and model intercomparison

    Energy Technology Data Exchange (ETDEWEB)

    Biancotto, R.; Coraluppi, L.; Pistollato, S.; Rosa, M.; Tarabotti, E. [Veneto Region Environmental Protection Agency - Dept. of Venice, Mestre (Italy); Liguori, F.; Lorenzet, K.; Pillon, S. [Veneto Region Environmental Protection Agency - Regional Air Observatory, Mestre (Italy); Maffeis, G.R. [Terraria srl, Milano (Italy)

    2004-07-01

    Mestre is the mainland part of the City of Venice, one of the most densely populated urban centres in the Veneto Region. Its ring road is a 6-lane motorway, 8 kilometre long, passing through the urban centre (see. Figure 2). It is a toll-free elevated road, located in the intersection between the most important motorways in North-East Italy: the A4 motorway, connecting NW to NE Italy, and the A27 motorway that is part of the link between Southern and Northern Italy. The ring road is used not only for long-range travels, but also to drive through the urban area of Mestre, avoiding the urban network of roads. During winter time, average daily traffic (ADT) counts up to 40,000 vehicles. 60% is represented by Light Duty Vehicles (LDV), while the remaining 40% by Heavy Duty Vehicles (HDV). The highest ADT counts up to 65,000 vehicles, where 90% is represented by LDV while 10% by HDV. This ADT has been recorded in the summer season, when commuter and commercial travels add to vacation travels, whose destination are the beaches in the Veneto region coastline. (orig.)

  19. Virtual queuing at airport security lanes

    NARCIS (Netherlands)

    Lange, de R.; Samoilovich, I.; Rhee, van der B.

    2013-01-01

    Airports continuously seek opportunities to reduce the security costs without negatively affecting passenger satisfaction. In this paper, we investigate the possibilities of implementing virtual queuing at airport security lanes, by offering some passengers a time window during which they can arrive

  20. Modeling merging behavior at lane drops.

    Science.gov (United States)

    2015-02-01

    In work-zone configurations where lane drops are present, merging of traffic at the taper presents an operational concern. In : addition, as flow through the work zone is reduced, the relative traffic safety of the work zone is also reduced. Improvin...

  1. Evaluating the Interference of Bicycle Traffic on Vehicle Operation on Urban Streets with Bike Lanes

    Directory of Open Access Journals (Sweden)

    Ziyuan Pu

    2017-01-01

    Full Text Available Many urban streets are designed with on-street bike lanes to provide right-of-way for bicycle traffic. However, when bicycle flow is large, extensive passing maneuvers could occupy vehicle lanes and thus cause interferences to vehicle traffic. The primary objective of this study is to evaluate how bicycle traffic affects vehicle operation on urban streets with bike lanes. Data were collected on six street segments in Nanjing, China. The cumulative curves were constructed to extract traffic flow information including individual bicycle and vehicle speeds and aggregated traffic parameters such as flow and density. The results showed that as bicycle density on bike lanes continuously increases faster bicycles may run into vehicle lanes causing considerable reductions in vehicle speeds. A generalized linear model was estimated to predict the vehicle delay. Results showed that vehicle delay increases as bicycle flow and vehicle flow increase. Number of vehicle lanes and width of bike lane also have significant impact on vehicle delay. Findings of the study are helpful to regions around the world in bike infrastructure design in order to improve operations of both bicycles and vehicles.

  2. Deep Neural Network for Structural Prediction and Lane Detection in Traffic Scene.

    Science.gov (United States)

    Li, Jun; Mei, Xue; Prokhorov, Danil; Tao, Dacheng

    2017-03-01

    Hierarchical neural networks have been shown to be effective in learning representative image features and recognizing object classes. However, most existing networks combine the low/middle level cues for classification without accounting for any spatial structures. For applications such as understanding a scene, how the visual cues are spatially distributed in an image becomes essential for successful analysis. This paper extends the framework of deep neural networks by accounting for the structural cues in the visual signals. In particular, two kinds of neural networks have been proposed. First, we develop a multitask deep convolutional network, which simultaneously detects the presence of the target and the geometric attributes (location and orientation) of the target with respect to the region of interest. Second, a recurrent neuron layer is adopted for structured visual detection. The recurrent neurons can deal with the spatial distribution of visible cues belonging to an object whose shape or structure is difficult to explicitly define. Both the networks are demonstrated by the practical task of detecting lane boundaries in traffic scenes. The multitask convolutional neural network provides auxiliary geometric information to help the subsequent modeling of the given lane structures. The recurrent neural network automatically detects lane boundaries, including those areas containing no marks, without any explicit prior knowledge or secondary modeling.

  3. Rural casualty crashes on the Kings Highway: A new approach for road safety studies.

    Science.gov (United States)

    Alian, Sahar; Baker, R G V; Wood, Stephen

    2016-10-01

    This paper will consider the contribution that changes in road geometry and driver visual information make to the incidence and distribution of road casualties in different driving environments. This relationship will be explored specifically for the Kings Highway, a major arterial road connecting Queanbeyan with coastal southern New South Wales, Australia. It introduces and suggests a new empirical approach of plotting crashes with road segmentation, calculating sinuosity indices and grades as key features of road geometry, and critical visual points as a behavioural component of road curvature, within a GIS context. It is an approach that might be used when detailed road geometry data is not available. The visualisation and segmentation approach in this research might be used for summarising crash rates and road geometry factors, and for comparing day/night and eastbound/westbound driving conditions. The results suggest some early interpretations for detailed road safety studies that might be considered at local or national levels. The rate of crashes increases according to changes in road geometry factors during the day and for eastbound travel. This is not the case for night driving where the incidence of crashes is similar on both straight and curved roads segments due to the headlight effect and limited background visual field. Crash clusters at day-time may be due to the stronger effect of road geometry (e.g. combination of curvature and vertical grade) on driver behaviour travelling eastbound. The outcomes suggest that it might be essential to consider the effect of environmental factors in any road safety and crash analysis studies. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Video-based lane estimation and tracking for driver assistance: Survey, system, and evaluation

    OpenAIRE

    McCall, J C; Trivedi, Mohan Manubhai

    2006-01-01

    Driver-assistance systems that monitor driver intent, warn drivers of lane departures, or assist in vehicle guidance are all being actively considered. It is therefore important to take a critical look at key aspects of these systems, one of which is lane-position tracking. It is for these driver-assistance objectives that motivate the development of the novel "video-based lane estimation and tracking" (VioLET) system. The system is designed using steerable filters for robust and accurate lan...

  5. Experimental study of the vehicle dynamics behavior during lane changing in different speeds

    Science.gov (United States)

    Heerwan, P. M.; Asyraf, S. M.; Efistein, A. N.; Seah, C. H.; Zikri, J. M.; Syawahieda, J. N.

    2017-10-01

    During lane changing, the speed of the vehicle is related to the stability of the vehicle. If the driver changes the lane at a high speed, the vehicle will lose its stability and it can increase the possibility of an accident. In this study, the experiment has been developed to analyse how the speed of the vehicle can affect the vehicle dynamics behavior. To achieve this objective, the UMP Test Car which employed with global positioning system (GPS), steering torque and angle sensor, displacement sensor and gyro sensor is used in the experiment. The experiment is run at the UMP test track and the track has 2 lanes which can allows the vehicle to change the position from the left to the right. In the experiment, when the GPS monitor shows 30 km/h, the driver will maintain the speed and start to turn the steering just after the test car reaches to the first skittle. Then, the driver will turn again the steering when the test car reaches to the second skittle. This method is repeated two times and the same methods is used for the speed 50 km/h. The data from the sensors is recorded in the Dewetron software and the graph is plotted. From the experimental results, the steering angle, steering torque, yaw rate and displacement for the speed 30 km/h is smaller than 50 km/h. It means that during lane changing, the speed 30 km/h is more stable compared with 50 km/h.

  6. Investigating the Impact of Road Condition Complexity on Driving Workload Based on Subjective Measurement using NASA TLX

    Directory of Open Access Journals (Sweden)

    Sugiono Sugiono

    2017-01-01

    Full Text Available Prior researchers indicate that mental load is one of the most important contributors to a traffic accident. The aim of the paper is to investigate the impact and the correlation of road condition and driving experience on driver’s mental workload. The driving test consists of 3 road complicity situation (urban road, highway, rural road with 26 drivers with average 21 years old in different experience level (average 4.08 years’ experience. NASA TLX questioner is used as subjective driver’s mental load measurement with three dimensions relate to the demands imposed on the subject (Mental, Physical and Temporal Demands and three to the interaction of a subject with the task (Effort, Frustration, and Performance. There are 3 cameras placed on the left side, right side and front car to identify the road condition. According to experiment, it was found that drivers felt that frustration level, business, and mental-demand factors dominate the impact on high-level workload (96.15%. Highway road conditions provide an average overall workload score of 62 (OWS which was better compared to city road (OWS = 69 and rural road (OWS = 66. Based on street complexity, it is necessary to improve road conditions that resemble highway road by reducing potential hazard.

  7. Microscopic origin and macroscopic implications of lane formation in mixtures of oppositely driven particles

    Science.gov (United States)

    Klymko, Katherine; Geissler, Phillip L.; Whitelam, Stephen

    2016-08-01

    Colloidal particles of two types, driven in opposite directions, can segregate into lanes [Vissers et al., Soft Matter 7, 2352 (2011), 10.1039/c0sm01343a]. This phenomenon can be reproduced by two-dimensional Brownian dynamics simulations of model particles [Dzubiella et al., Phys. Rev. E 65, 021402 (2002), 10.1103/PhysRevE.65.021402]. Here we use computer simulation to assess the generality of lane formation with respect to variation of particle type and dynamical protocol. We find that laning results from rectification of diffusion on the scale of a particle diameter: oppositely driven particles must, in the time taken to encounter each other in the direction of the drive, diffuse in the perpendicular direction by about one particle diameter. This geometric constraint implies that the diffusion constant of a particle, in the presence of those of the opposite type, grows approximately linearly with the Péclet number, a prediction confirmed by our numerics over a range of model parameters. Such environment-dependent diffusion is statistically similar to an effective interparticle attraction; consistent with this observation, we find that oppositely driven nonattractive colloids display features characteristic of the simplest model system possessing both interparticle attractions and persistent motion, the driven Ising lattice gas [Katz, Leibowitz, and Spohn, J. Stat. Phys. 34, 497 (1984), 10.1007/BF01018556]. These features include long-ranged correlations in the disordered regime, a critical regime characterized by a change in slope of the particle current with the Péclet number, and fluctuations that grow with system size. By analogy, we suggest that lane formation in the driven colloid system is a phase transition in the macroscopic limit, but that macroscopic phase separation would not occur in finite time upon starting from disordered initial conditions.

  8. A high accuracy vehicle positioning system implemented in a lane assistance system when GPS Is unavailable.

    Science.gov (United States)

    2011-07-01

    The use of lane assistance systems can reduce the stress levels experienced by drivers and allow for better lane : keeping in narrow, bus-dedicated lanes. In 2008, the Intelligent Vehicles (IV) Lab at the University of Minnesota : has developed such ...

  9. Prediction of road accidents: A Bayesian hierarchical approach.

    Science.gov (United States)

    Deublein, Markus; Schubert, Matthias; Adey, Bryan T; Köhler, Jochen; Faber, Michael H

    2013-03-01

    In this paper a novel methodology for the prediction of the occurrence of road accidents is presented. The methodology utilizes a combination of three statistical methods: (1) gamma-updating of the occurrence rates of injury accidents and injured road users, (2) hierarchical multivariate Poisson-lognormal regression analysis taking into account correlations amongst multiple dependent model response variables and effects of discrete accident count data e.g. over-dispersion, and (3) Bayesian inference algorithms, which are applied by means of data mining techniques supported by Bayesian Probabilistic Networks in order to represent non-linearity between risk indicating and model response variables, as well as different types of uncertainties which might be present in the development of the specific models. Prior Bayesian Probabilistic Networks are first established by means of multivariate regression analysis of the observed frequencies of the model response variables, e.g. the occurrence of an accident, and observed values of the risk indicating variables, e.g. degree of road curvature. Subsequently, parameter learning is done using updating algorithms, to determine the posterior predictive probability distributions of the model response variables, conditional on the values of the risk indicating variables. The methodology is illustrated through a case study using data of the Austrian rural motorway network. In the case study, on randomly selected road segments the methodology is used to produce a model to predict the expected number of accidents in which an injury has occurred and the expected number of light, severe and fatally injured road users. Additionally, the methodology is used for geo-referenced identification of road sections with increased occurrence probabilities of injury accident events on a road link between two Austrian cities. It is shown that the proposed methodology can be used to develop models to estimate the occurrence of road accidents for any

  10. Comparison of the predictions of two road dust emission models with the measurements of a mobile van

    Science.gov (United States)

    Kauhaniemi, M.; Stojiljkovic, A.; Pirjola, L.; Karppinen, A.; Härkönen, J.; Kupiainen, K.; Kangas, L.; Aarnio, M. A.; Omstedt, G.; Denby, B. R.; Kukkonen, J.

    2014-09-01

    The predictions of two road dust suspension emission models were compared with the on-site mobile measurements of suspension emission factors. Such a quantitative comparison has not previously been reported in the reviewed literature. The models used were the Nordic collaboration model NORTRIP (NOn-exhaust Road TRaffic Induced Particle emissions) and the Swedish-Finnish FORE model (Forecasting Of Road dust Emissions). These models describe particulate matter generated by the wear of road surface due to traction control methods and processes that control the suspension of road dust particles into the air. An experimental measurement campaign was conducted using a mobile laboratory called SNIFFER, along two selected road segments in central Helsinki in 2007 and 2008. The suspended PM10 concentration was measured behind the left rear tyre and the street background PM10 concentration in front of the van. Both models reproduced the measured seasonal variation of suspension emission factors fairly well during both years at both measurement sites. However, both models substantially under-predicted the measured emission values. The article illustrates the challenges in conducting road suspension measurements in densely trafficked urban conditions, and the numerous requirements for input data that are needed for accurately applying road suspension emission models.

  11. 75 FR 22578 - Application To Export Electric Energy; Centre Lane Trading Limited

    Science.gov (United States)

    2010-04-29

    ... DEPARTMENT OF ENERGY [OE Docket No. EA-365] Application To Export Electric Energy; Centre Lane... application. SUMMARY: Centre Lane Trading Limited (CLT) has applied for authority to transmit electric energy...)). On April 20, 2010, DOE received an application from CLT for authority to transmit electric energy...

  12. Delays in accessing electroconvulsive therapy: a comparison between two urban and two rural populations in Australia.

    Science.gov (United States)

    Johnston, Natalie E

    2015-10-01

    A comparison of the timing, rates and characteristics of electroconvulsive therapy use between urban and rural populations. The medical records of patients who received an acute course of electroconvulsive therapy at two rural and two urban psychiatric hospitals in New South Wales (NSW), Australia, in 2010 were reviewed retrospectively. Main outcome measures were the time from symptom onset, diagnosis and admission to commencing electroconvulsive therapy. Rates of use of electroconvulsive therapy were also compared between rural and urban hospitals using NSW statewide data. There was a significant delay in the time it took for rural patients to receive electroconvulsive therapy compared with urban patients when measured both from the time of symptom onset and from when they received a diagnosis. There were corresponding delays in the time taken for rural patients to be admitted to hospital compared with urban patients. There was no difference in the time it took to commence electroconvulsive therapy once a patient was admitted to hospital. NSW statewide urban-rural comparisons showed rates of electroconvulsive therapy treatment were significantly higher in urban hospitals. Patients in rural areas receive electroconvulsive therapy later in their acute illness due to delays in being admitted to hospital. The rate of use of electroconvulsive therapy also differs geographically. © The Royal Australian and New Zealand College of Psychiatrists 2015.

  13. Socio-demographic impacts on lane-changing response time and distance in work zone with Drivers' Smart Advisory System

    Directory of Open Access Journals (Sweden)

    Qing Li

    2015-10-01

    Full Text Available Lane-changing behavior is an important component of traffic simulation. A lane-changing action is normally confined to a decision-making process of the task, and the action itself is sometimes assumed as an instantaneous event. Besides, the lane-changing behavior is based mostly on observable positions and speeds of other vehicles, rather than on vehicles' intentions. In practice, changing one lane requires about 5–6 s to complete. Existing lane-changing models do not comprehensively consider drivers' response to work zone lane-changing signs (or other related messages, if any. Furthermore, drivers' socio-demographics are normally not taken into account. With regard to this, fuzzy logic-based lane-changing models that consider drivers' socio-demographics were developed to improve the realism of lane-changing maneuvers in work zones. Drivers' Smart Advisory System (DSAS messages were provided as one of the scenarios. Drivers' responses, including reactions to work zone signs and DSAS messages, and actions to change lane, were investigated. Drivers' socio-demographic factors were primary independent variables, while Lane-Changing Response Time (LCRT and Distance (LCRD were defined as output variables. The model validation process yielded acceptable error ranges. To illustrate how these models can be used in traffic simulation, the LCRT and LCRD in work zones were estimated for five geo-locations with different socio-demographic specifications. Results show that the DSAS is able to instruct all drivers to prepare and change lanes earlier, thereby shortening the duration of changing lanes. Educational background and age are essential variables, whereas the impacts of gender on the output variables are indistinctive.

  14. The Role of Public Infrastructure in Market Development in Rural Peru

    OpenAIRE

    Escobal, J.A.

    2005-01-01

    Keywords:Peru, rural infrastructure, poverty, economic geography, rural roads, impact evaluation, non-agricultural employment.This study provides a conceptual framework toanalysethe impact of rural infrastructure investment on market development for the enhancement of income generating opportunities for the poor in ruralPeru. The study uses descriptive methods and regression analysis together with relatively new impact evaluation techniques, like propensity score matching, to understand the c...

  15. Controller Design and Evaluation of Lane-Keeping-Assistance System for Motorcycles

    Science.gov (United States)

    Katagiri, Nozomi; Marumo, Yoshitaka; Tsunashima, Hitoshi

    This study seeks to design a lane keeping controller for motorcycles and to evaluate it by computer simulation with a four-degree-of-freedom model and a rider control model. We applied the optimal control theory to the lane keeping controller as a model-based control. By examining the computer simulation with the rider-in-the-loop system consisting of the motorcycle, the controller, and the rider control model, good lane following performance is achieved without interference between the control input and the rider's input. In addition, the virtual point regulator, which compensates the lateral displacement at the virtual point ahead of the vehicle, corresponds to not only the steering torque disturbance but also the lateral force disturbance by choosing the distance to the virtual point.

  16. Lane fuzzy collision in channel with potential deformation by photon-phonon-electron excitation and sub-atomic control

    International Nuclear Information System (INIS)

    Shen Jing

    1998-01-01

    Collision between μ + and the μ - beams in the crystal are forbidden due to the two beams having different ''lanes'' in a channel. A laser pulse of ps-fs shocks lattice kernel vibration and dilates lattice electron distribution. It deforms the Lindhard's potential which is then expressed in a quantized form as the Huang-Zhu's potential[1]. The dynamic lanes can be made to overlap in a channel to allow collision without ductile fracture. This raises a new technology of sub-atomic information and control, which has been raised by T. D. Lee

  17. Response of moose to a high‐density road network

    Science.gov (United States)

    Wattles, David W.; Zeller, Katherine A.; DeStefano, Stephen

    2018-01-01

    Road networks and the disturbance associated with vehicle traffic alter animal behavior, movements, and habitat selection. The response of moose (Alces americanus) to roads has been documented in relatively rural areas, but less is known about moose response to roads in more highly roaded landscapes. We examined road‐crossing frequencies and habitat use of global positioning system (GPS)‐collared moose in Massachusetts, USA, where moose home ranges have road densities approximately twice that of previous studies. We compared seasonal road‐crossing frequencies of moose with a null movement model. We estimated moose travel speeds during road‐crossing events and compared them with speeds during other home range movements. To estimate the extent of the road effect zone and determine how roads influenced moose habitat use, we fit a third‐order resource selection function. With the exception of the lowest use road class (roads less than expected based on the null movement model and frequency decreased with increasing road size and traffic. Moose crossed roads faster than they traveled during other times. This effect increased with increasing road use intensity. Overall, roads were a major factor determining what portions of Massachusetts moose used and how they moved among habitat patches. Our results suggest that moose in Massachusetts can adapt to a high‐density road network, but the road effect is still strongly negative and, in some cases, is more pronounced than in study areas with lower road densities. Future road construction and the expansion of road networks may have a large effect on moose and other wildlife.

  18. Crowd of individuals walking in opposite directions. A toy model to study the segregation of the group into lanes of individuals moving in the same direction

    Science.gov (United States)

    Goldsztein, Guillermo H.

    2017-08-01

    Consider a corridor, street or bridge crowded with pedestrians walking in both directions. The individuals do not walk in a completely straight line. They adjust their path to avoid colliding with incoming pedestrians. As a result of these adjustments, the whole group sometimes end up split into lanes of individuals moving in the same direction. While this formation of lanes facilitates the flow and benefits the whole group, it is believed that results from the actions of the individuals acting only on their behalf, without considering others. This phenomenon is an example of self-organization. We analyze a simple model. We assume that individuals move around a two-lane circular track. All of them at the same speed. Half of them in one direction and the rest in the opposite direction. Each time two individuals collide, one of them moves to the other lane. The individual changing lanes is selected randomly. The system self-organizes. Eventually each lane is occupied with individuals moving in only one direction. We show that the time required for the system to self-organize is bounded by a linear function on the number of individuals. This toy model provides an example where global self-organization occurs even though each member of the group acts without considering the rest.

  19. CMOS Image Sensor with a Built-in Lane Detector

    Directory of Open Access Journals (Sweden)

    Li-Chen Fu

    2009-03-01

    Full Text Available This work develops a new current-mode mixed signal Complementary Metal-Oxide-Semiconductor (CMOS imager, which can capture images and simultaneously produce vehicle lane maps. The adopted lane detection algorithm, which was modified to be compatible with hardware requirements, can achieve a high recognition rate of up to approximately 96% under various weather conditions. Instead of a Personal Computer (PC based system or embedded platform system equipped with expensive high performance chip of Reduced Instruction Set Computer (RISC or Digital Signal Processor (DSP, the proposed imager, without extra Analog to Digital Converter (ADC circuits to transform signals, is a compact, lower cost key-component chip. It is also an innovative component device that can be integrated into intelligent automotive lane departure systems. The chip size is 2,191.4 x 2,389.8 mm, and the package uses 40 pin Dual-In-Package (DIP. The pixel cell size is 18.45 x 21.8 mm and the core size of photodiode is 12.45 x 9.6 mm; the resulting fill factor is 29.7%.

  20. CMOS Image Sensor with a Built-in Lane Detector.

    Science.gov (United States)

    Hsiao, Pei-Yung; Cheng, Hsien-Chein; Huang, Shih-Shinh; Fu, Li-Chen

    2009-01-01

    This work develops a new current-mode mixed signal Complementary Metal-Oxide-Semiconductor (CMOS) imager, which can capture images and simultaneously produce vehicle lane maps. The adopted lane detection algorithm, which was modified to be compatible with hardware requirements, can achieve a high recognition rate of up to approximately 96% under various weather conditions. Instead of a Personal Computer (PC) based system or embedded platform system equipped with expensive high performance chip of Reduced Instruction Set Computer (RISC) or Digital Signal Processor (DSP), the proposed imager, without extra Analog to Digital Converter (ADC) circuits to transform signals, is a compact, lower cost key-component chip. It is also an innovative component device that can be integrated into intelligent automotive lane departure systems. The chip size is 2,191.4 × 2,389.8 μm, and the package uses 40 pin Dual-In-Package (DIP). The pixel cell size is 18.45 × 21.8 μm and the core size of photodiode is 12.45 × 9.6 μm; the resulting fill factor is 29.7%.

  1. Not just a rural occurrence: differences in agricultural equipment crash characteristics by rural-urban crash site and proximity to town.

    Science.gov (United States)

    Harland, Karisa K; Greenan, Mitchell; Ramirez, Marizen

    2014-09-01

    Although approximately one-third of agricultural equipment-related crashes occur near town, these crashes are thought to be a rural problem. This analysis examines differences between agricultural equipment-related crashes by their urban-rural distribution and distance from a town. Agricultural equipment crashes were collected from nine Midwest Departments of Transportation (2005-2008). Crash zip code was assigned as urban or rural (large, small and isolated) using Rural-Urban Commuting Areas. Crash proximity to a town was estimated with ArcGIS. Multivariable logistic regression was used to estimate the odds of crashing in an urban versus rural zip codes and across rural gradients. ANOVA analysis estimated mean distance (miles) from a crash site to a town. Over four years, 4444 crashes involved agricultural equipment. About 30% of crashes occurred in urban zip codes. Urban crashes were more likely to be non-collisions (aOR=1.69[1.24-2.30]), involve ≥2 vehicles (2 vehicles: aOR=1.58[1.14-2.20], 3+ vehicles: aOR=1.68[0.98-2.88]), occur in a town (aOR=2.06[1.73-2.45]) and within one mile of a town (aOR=1.65[1.40-1.95]) than rural crashes. The proportion of crashes within a town differed significantly across rural gradients (Purban-rural distribution (Pagricultural equipment are unexpectedly common in urban areas and near towns and cities. Education among all roadway users, increased visibility of agricultural equipment and the development of complete rural roads are needed to increase road safety and prevent agricultural equipment-related crashes. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Pollutant concentrations in road runoff: Southeast Queensland case study

    Energy Technology Data Exchange (ETDEWEB)

    Drapper, D.; Tomlinson, R.; Williams, P.

    2000-04-01

    This paper discusses the results of research into the pollutants in runoff from road pavement surfaces following natural rainfall events. Road runoff water quality was monitored at 21 sites centering around Brisbane, in southeast Queensland, Australia. The sites were selected according to traffic volumes, surrounding land use, pavement surface type, ease of access, and commercial vehicle percentage. Bridge sites were chosen for convenience of sample collection and minimized infrastructure modification. First flush grab samplers were permanently installed at each site to collect the first 20 L of runoff from one of the bridge drainage scuppers. The runoff samples were tested for a number of heavy metals, hydrocarbons, pesticides, and other physical characteristics. The observed results fall within the ranges of concentrations reported internationally and nationally but do not typically follow the 30,000 average annual daily traffic results reported in the United States. Traffic volumes have not been found to be the best indicator of road runoff pollutant concentrations. Interevent duration has been found to be a statistically significant factor for pollutant concentrations. Sites incorporating exit lanes have recorded higher concentrations of acid-extractable copper and zinc, tending to support the hypothesis that brake pad and tire wear caused by rapid deceleration contributes to the concentrations of these metals in road runoff. Laser particle sizing has shown that a significant proportion of the sediment found in the runoff is <100 {micro}m. However, these particulates do settle in water within 24 h, under laboratory conditions. This may be due to the presence of heavy metals.

  3. Development of road infrastructure as a tool of transforming Ibiono ...

    African Journals Online (AJOL)

    Global Journal of Social Sciences ... Development of road infrastructure as a tool of transforming Ibiono Ibom local government area. V Umoren ... The improvement of transportation network in the rural area in this regard becomes imperative.

  4. Does the Walker Lane extend through the Nevada test site region?

    International Nuclear Information System (INIS)

    Fridrich, C.; O'Leary, D.

    1993-01-01

    The southeastern terminus of the Walker Lane is poorly defined and poorly understood. Recent work in and around the Nevada Test Site (NTS) suggests the presence of a structural zone that may be an extension of the Walker Lane, and that may be continuous with the Las Vegas valley shear zone farther to the southeast. Unlike the Walker Lane, large through-going strike-slip faults have not been found in the NTS zone. Instead, the strike-slip faults present are few, are relatively short, commonly consist of diffuse fault zones, are interconnected poorly if at all, and largely appear to represent zones of accommodation between domains in which extension occurred at different times and to different degrees. However, the majority of these right-slip and left-slip faults are northwest-trending and northeast-trending, respectively, suggesting that plate motions may have played a role in the creation of these accommodation zones. An obstacle to understanding the NTS zone is that major ignimbrite sheets and calderas of the southwestern Nevada volcanic field (SNVF) formed in this zone at the height of late Tertiary tectonic activity, possibly burying much of the structural evidence. The NTS zone could represent an intersection of the Walker Lane with another major structural feature, a significant bend in the Walker Lane, or a transtensional tear that localized accommodation structures as well as the prominent late Miocene calderas of the SNVF. Ongoing field work is aimed at determining which of these and competing interpretations is best

  5. Low Impact Development Intensive Rural Construction Planning in Xu Fu Village Ningbo, China: Planning Review through Rural Resilience Perspective

    Directory of Open Access Journals (Sweden)

    Roosmayri Lovina Hermaputi

    2017-08-01

    Full Text Available Xu Fu Village Ningbo LID Intensive Rural Construction Planning is a cooperation project between Zhejiang University and Ningbo Institute of Technology which named "12th Five-Year National Science and Technology support program-the comprehensive demonstration of the key technology of the beautiful rural construction in the rapid urbanization area of the Yangtze River Delta". This plan focuses on intensive rural construction as part of rural development and construction project that applies the principles of low impact development. Xu Fu Village located in the Yangtze River Delta Region. Currently, the rural growth brings the high impact of development, as a result of rapid urbanization growth arising several issues, such as low land use efficiency, dispersed rural residence, homestead occupies more, rural roads covering over, etc. Meanwhile, Xu Fu village wishes to develop its tourism potential. Thus, the intensive rural construction should be done to avoid the severe effect. The project result hopefully can improve the quality and level of rural residential planning, design, and construction; improve their living environment; save construction land and water use; and improve energy efficiency. The aim of this study is to review the Low Impact Development (LID Intensive Rural Construction in Xu Fu Village, Ningbo City through the rural resilience perspective. This paper will describe the project plan first, then review it through rural resilience perspective. This paper will elaborate the rural resilience theory and then review the rural resiliency through two parts; the first part is identifying rural resilience in rural infrastructure development based on the criteria created by Ayyob S. and Yoshiki Y. (2014, about urban resiliency criteria, and then the second part is reviewing Xu Fu Village resilience through Arup Resilience Qualities (2012, considering three rural resilience domain (economy, ecology, and cultural.

  6. Investigating the value of time and value of reliability for managed lanes : [summary].

    Science.gov (United States)

    2015-09-01

    Managed lanes employ various operational and design strategies to improve highway : efficiency by moving traffic to lanes that are restricted, for example, to drivers with one or : more passengers or to drivers that pay a fee. A drivers decision t...

  7. Effective public communication and marketing of high-occupancy-vehicle lanes : an agency perspective

    Science.gov (United States)

    1997-01-01

    The Massachusetts Highway Department (MassHighway) opened the Southeast Expressway high-occupancy-vehicle (HOV) lane on November 15, 1995. The 6-mi (9.6-km) contraflow lane, open to vehicles with at least three occupants, was MassHighways third at...

  8. A summary of design, policies and operational characteristics for shared bicycle/bus lanes.

    Science.gov (United States)

    2012-07-01

    This report contains the results of an investigation of the design and operation of shared bicycle/bus lanes in municipalities in the United States and other countries. These lanes are designated for use by public transit buses, bicycles, and usually...

  9. Two Belts, One Road? - The role of Africa in Chinas's Belt & Road initiative

    OpenAIRE

    Breuer, Julia

    2017-01-01

    In the light of the EU-Africa Summit 2017 and of the G20 Summit 2017 with Africa being one of the focus areas, China’s engagement in Africa seems more relevant than ever. China’s “One Belt, One Road” initiative (OBOR) or silk road initiative is often referred to as a Eurasian infrastructure network initiative, but it is in fact much more than that. The maritime silk road is supposed to go past the coast of East Africa, where several ports are being built and will be built. Furthermore, ports ...

  10. ROADSIDE BARRIER AND PASSIVE SAFETY OF MOTORCYCLISTS ALONG EXCLUSIVE MOTORCYCLE LANES

    Directory of Open Access Journals (Sweden)

    A.B. IBITOYE

    2007-04-01

    Full Text Available The tremendous increase in number of motorcycles and fatalities in some ASEAN countries is becoming a main concern for the safety of motorcyclists along exclusive motorcycle lanes. The existing w-beam guardrail system along exclusive motorcycle lanes was originally designed to reduce severity of a crash when cars and trucks involve in run-off road accident – but not specifically to protect motorcyclists during such accident. However, the consequences of this guardrail design on the passive safety of motorcyclist have been given little consideration. Thus, Probability of the motorcyclists getting injured on collision with guardrail is higher compared to other motor vehicle’s driver. In order to investigate the passive safety of motorcyclists while in collision with this guardrail, this study carried out computer simulation of typical crash scenario and conducted a physical crash test to validate the simulation model. The study examines the crash mechanism as related to injury severity when motorcyclist interacts with W-beam guardrail. A three-dimensional computer simulation of a scaled Hybrid III 50th percentile Male dummy mounted on a motorcycle and colliding with W-beam guardrail was carried out. Multi-body model of motorcycle and finite element model of guardrail were developed with commercially available software called MADYMO. The simulation model is validated with a simple crash test conducted with same initial impact configuration. The subsequent simulations were set up for impacting the existing w-beam guardrail with 110 kg motorcycle using eighteen impact conditions that consist of impact angles 15o, 30o and 45o, impact speeds of 32, 48 and 60km/h as well as post spacing of 2m and 4m. The predicted rider’s injury risk criteria were used to assess safety of guardrail response to motorcyclists. The obtained results confirmed that the existing w-beam guardrail is not safe to motorcyclist, especially for the head injury at impact speed

  11. Nonlinear model predictive control of a passenger vehicle for automated lane changes

    NARCIS (Netherlands)

    Acosta, A.F.; Marquez-Ruiz, A.; Espinosa, J.J.

    2017-01-01

    This article presents a nonlinear Model Predictive Control (MPC) for lane changes, based on a simplified Single Track Model (STM) of the vehicle. The STM includes the position of the vehicle in global coordinates as a state so that the position of the target lane can be specified to the MPC for

  12. Invasive Brown Treesnake movements at road edges indicate road-crossing avoidance

    Science.gov (United States)

    Siers, Shane R.; Savidge, Julie S; Reed, Robert N.

    2014-01-01

    Roads have significant impacts on the dispersal of wildlife. Although this poses a threat to the abundance and diversity of desirable flora and fauna, it also affords some opportunity for enhancing control of invasive species. Roads are the most common terrain features that may affect the rate of landscape-scale movements of invasive Brown Treesnakes (Boiga irregularis) throughout Guam. We radio tracked 45 free-ranging Brown Treesnakes in close proximity to two roads in Guam and recorded instances where daily relocations of snakes spanned roads. Then we reconstructed observed movement histories with randomized turning angles, which served as a useful null hypothesis for assessing the effect of roads or road edge habitat on Brown Treesnake movement patterns. Random walk simulations demonstrated that Brown Treesnakes crossed these roads at a rate far lower than would be expected if snake movement was random with respect to roads and road edge habitat. We discuss two alternative hypotheses for these results: 1) habitat gaps posed by roads physically or behaviorally restrict snake movement; or 2) road edges provide preferred foraging habitat from which snakes are reluctant to depart. Because roads often form the boundaries of jurisdictional and management units, the effects of roads on the movement of invasive Brown Treesnakes will influence the prospects for success of future landscape-level suppression efforts.

  13. Strabo's roads

    DEFF Research Database (Denmark)

    Bekker-Nielsen, Tønnes

    2017-01-01

    in the Geography, and the world-view, of Strabo. Strabo did not take much interest in roads as artefacts or monuments, in the technology of road construction, or in the mythological and historical background of individual roads. He is primarily interested in roads from a functional point of view. For the general......To ancient geographers, roads were important not only as arteries of communication, but also as sources of information, since mileages measured along the Roman highways were among the very few precise distances available to the ancient geographer. This chapter explores the place of roads...... or the statesman, roads provide routes of communication; for the systematic geographer, they provide measured distances and directions. Through case studies of Spain, Gaul, Italy, Greece and Anatolia, this chapter attempts to reach a better understanding of the place of roads in Strabo’s universe, especially two...

  14. Rural workload: study performed in two rural environments in the state of Rio Grande do Sul, Brazil

    Directory of Open Access Journals (Sweden)

    Laurelize Pereira Rocha

    2016-05-01

    Full Text Available ABSTRACT: This study aimed to analyze loads resulting from the rural work of fruit and vegetable farmers. This exploratory and descriptive study was conducted with 259 farm workers from two rural environments. A semi-structured questionnaire based on the concepts of NASA-TLX was used to assess workload. The male and female workers of one environment reported that the demand that contributed the most to their workload was the level of total effort, while the women of the other environment reported that the physical demand was more relevant for WL. In conclusion, evidence concerning workload supports further investigation into the health of rural workers and the development of preventive strategies related to rural work.

  15. Bird communities in two oceanic island forests fragmented by roads ...

    African Journals Online (AJOL)

    Although most studies on road effects on birds have been conducted on continental grounds, road fragmentation on oceanic islands is often heavier. We assessed variation in bird communities near (≤ 25 m) and far (>100 m) from forest roads dividing laurel and pine forests on Tenerife, Canary Islands. Line transects were ...

  16. Examining physiological responses across different driving maneuvers during an on-road driving task: a pilot study comparing older and younger drivers.

    Science.gov (United States)

    Koppel, S; Kuo, J; Berecki-Gisolf, J; Boag, R; Hue, Y-X; Charlton, J L

    2015-01-01

    This pilot study aimed to investigate physiological responses during an on-road driving task for older and younger drivers. Five older drivers (mean age = 74.60 years [2.97]) and 5 younger drivers (mean age = 30.00 years [3.08]) completed a series of cognitive assessments (Montreal Cognitive Assessment [MoCA], Mini Mental Status Examination [MMSE]; Trail Making Test [Trails A and Trails B]) and an on-road driving task along a predetermined, standardized urban route in their own vehicle. Driving performance was observed and scored by a single trained observer using a standardized procedure, where driving behaviors (appropriate and inappropriate) were scored for intersection negotiation, lane changing, and merging. During the on-road driving task, participants' heart rate (HR) was monitored with an unobtrusive physiological monitor. Younger drivers performed significantly better on all cognitive assessments compared to older drivers (MoCA: t(8) = 3.882, P task revealed a high level of appropriate overall driving behavior (M = 87%, SD = 7.62, range = 73-95%), including intersection negotiation (M = 89%, SD = 8.37%), lane changing (M = 100%), and merging (M = 53%, SD = 28.28%). The overall proportion of appropriate driving behavior did not significantly differ across age groups (younger drivers: M = 87.6%, SD = 9.04; older drivers: M = 87.0%, SD = 6.96; t(8) = 0.118, P =.91). Although older drivers scored lower than younger drivers on the cognitive assessments, there was no indication of cognitive overload among older drivers based on HR response to the on-road driving task. The results provide preliminary evidence that mild age-related cognitive impairment may not pose a motor vehicle crash hazard for the wider older driver population. To maintain safe mobility of the aging population, further research into the specific crash risk factors in the older driver population is warranted.

  17. An assessment of the skid resistance effect on traffic safety under wet-pavement conditions.

    Science.gov (United States)

    Pardillo Mayora, José M; Jurado Piña, Rafael

    2009-07-01

    Pavement-tire friction provides the grip that is required for maintaining vehicle control and for stopping in emergency situations. Statistically significant negative correlations of skid resistance values and wet-pavement accident rates have been found in previous research. Skid resistance measured with SCRIM and crash data from over 1750km of two-lane rural roads in the Spanish National Road System were analyzed to determine the influence of pavement conditions on safety and to assess the effects of improving pavement friction on safety. Both wet- and dry-pavement crash rates presented a decreasing trend as skid resistance values increased. Thresholds in SCRIM coefficient values associated with significant decreases in wet-pavement crash rates were determined. Pavement friction improvement schemes were found to yield significant reductions in wet-pavement crash rates averaging 68%. The results confirm the importance of maintaining adequate levels of pavement friction to safeguard traffic safety as well as the potential of pavement friction improvement schemes to achieve significant crash reductions.

  18. How the Guangzhou Government Can Curtail Air Pollution from Road Traffic in a Least Costly Manner

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Xu

    1998-12-01

    This thesis explores the relationship between the increased motorized traffic and air pollution in urban Guangzhou, the prosperous capital of the Guangdong Province in southern China that is located in the vicinity of Hong Kong and Macao. The emphasis is placed on PM 10 pollutants (particles of less than 10 microns in size). It reviews the current status of ambient air quality, the harmful effects of PM 10 emissions on human health and how to reduce the problem. It is estimated that 3300 premature deaths per year could be avoided if Guangzhou met the Class II of the Chinese National Ambient Air Quality Standard for PM 10, and the Guangzhou Government could save 10% of its GDP in 1994. A theoretical framework for reducing pollution problems is presented based on cost-effectiveness theory. There is also an overview of possible pollution reducing measures based on worldwide experience. The theoretical framework is applied to a case study of selected measures: (1) reduced sulfur content of diesel fuel, (2) creating bus lanes, (3) fuel taxation, (4) introduction of toll roads, (5) measures on the metro line. The bus lane measure is found to be the most cost-effective one, followed by the toll road and fuel taxation measures. The metro measure is the most expensive one. Finally, the report recommends to the Guangzhou Government what measures should have first priority according to cost-effectiveness. 23 refs., 14 figs., 21 tabs.

  19. Shipping Fairways, Lanes, and Zones for US waters

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Various shipping zones delineate activities and regulations for marine vessel traffic. Traffic lanes define specific traffic flow, while traffic separation zones...

  20. Risk Factor Profile of Motorcycle Crash Victims in Rural Kenya ...

    African Journals Online (AJOL)

    Background: Road traffic injuries involving motorcycles are increasing especially in rural Kenya resulting in both human and economic loss. This study was done to identify the risk factors and the host characteristics associated with motorcycle injury victims in rural setting so as to institute appropriate interventions for ...

  1. Policy options evaluation tool for managed lanes (POET-ML) users guide and methodology description : Federal Highway Administration HOV lane performance

    Science.gov (United States)

    2008-12-01

    Users guide for a sketch planning tool for exploring policy alternatives. It is intended for an audience of transportation professionals responsible for planning, designing, funding, operating, enforcing, monitoring, and managing HOV and HOT lanes...

  2. L’interaction urbain-rural : une problématique renouvelée Urban-rural interaction revisited

    Directory of Open Access Journals (Sweden)

    Christian Vandermotten

    2010-12-01

    Full Text Available La distinction entre l’urbain et le rural était claire sous l’Ancien Régime, dans des sociétés peu mobiles. La révolution industrielle accentue l’identification entre la ville, l’industrie et la modernité. Après la Seconde Guerre mondiale, le développement du transport routier affranchit l’industrie des localisations urbaines et la périurbanisation progresse. En même temps, l’accroissement des productivités agricoles libère de plus en plus de main-d’œuvre paysanne. Après deux siècles au moins d’exode rural, les campagnes se rurbanisent, mais cette rurbanisation s’inscrit dans un contexte global de mégapolisation. Cette configuration devrait imposer une nouvelle appréciation des rapports entre l’urbain et le rural, en ce compris leurs rapports politiques.The distinction between urban and rural was clear under the Ancien Régime, as societies featured a low level of mobility. The industrial revolution increased the identification between cities, manufacturing and modernity. After the Second World War, growing road traffic freed industries from urban locations and suburbanisation thus increased. Simultaneously, the increase in food productivity required fewer and fewer agricultural workers. After more than two centuries of rural exodus, rurbanisation transformed rural areas, even as this very process of rurbanisation should be seen as part of a global megapolization process. This pattern implies new kinds of relations between the rural and the urban, including from a political point of view.

  3. Rural poultry production in two agro-ecological zones of Uganda

    International Nuclear Information System (INIS)

    Illango, J.; Etoori, A.; Olupot, H.; Mabonga, J.

    2002-01-01

    A baseline study on rural poultry production, management and health was conducted in six selected villages in an agro-pastoral and montane zone of Uganda during the wet and dry season. In the 114 rural households visited, the farmers were interviewed by using a questionnaire. Poultry flocks were examined and samples were collected for laboratory investigations. A free-range management system with mixed poultry species was practiced by farmers in both zones. The major poultry flock parameters in the agro-pastoral and montane zone were, respectively, mean flock size of 22 (with a range of 3-65) and 17.5 (with a range of 6-60); mean hen:cock ratio of 2.6 to 1 and 4.8 to 1; mean egg production per hen per year of 8.8 and 11.5; mean hatchability of 70.8% and 85.7%; mean chick mortality of 39.6% and 28.6%. The flock ownership was single, mixed or shared among family households. Women were more involved in most of the activities regarding poultry management, although in both zones a division of labour existed within the household. Men predominantly made the decisions on sale, consumption and treatment of poultry. The most important health problems in the flocks in both zones in the two seasons were coughing, diarrhoea, fowl pox and internal parasites. It was concluded that the major constraints affecting rural poultry production in the two zones were diseases especially Newcastle disease and parasites, inadequate housing and poor feed supplementation especially in the dry season. Women had important responsibilities in rural poultry production in the two zones. The findings form the basis for an assessment of the effects of interventions on rural poultry production in the two zones. (author)

  4. Soil Landscape Pattern Changes in Response to Rural Anthropogenic Activity across Tiaoxi Watershed, China

    Science.gov (United States)

    Xiao, Rui; Jiang, Diwei; Christakos, George; Fei, Xufeng; Wu, Jiaping

    2016-01-01

    Soil sealing (loss of soil resources due to extensive land covering for the purpose of house building, road construction etc.) and subsequent soil landscape pattern changes constitute typical environmental problems in many places worldwide. Previous studies concentrated on soil sealing in urbanized regions, whereas rural areas have not been given sufficient attention. Accordingly, this paper studies soil landscape pattern dynamics (i.e., landscape pattern changes in response to rural anthropogenic activities) in the Tiaoxi watershed (Zhejiang province, eastern China), in which surface sealing is by far the predominant component of human forcing with respect to environmental change. A novel approach of quantifying the impacts of rural anthropogenic activities on soil resources is presented. Specifically, quantitative relationships were derived between five soil landscape pattern metrics (patch density, edge density, shape index, Shannon’s diversity index and aggregation index) and three rural anthropogenic activity indicators (anthropogenic activity intensity, distance to towns, and distance to roads) at two landscape block scales (3 and 5 km) between 1985 and 2010. The results showed that the Tiaoxi watershed experienced extensive rural settlement expansion and high rates of soil sealing. Soil landscapes became more fragmented, more irregular, more isolated, and less diverse. Relationships between soil landscape pattern changes and rural anthropogenic activities differed with the scale (spatial and temporal) and variable considered. In particular, the anthropogenic activity intensity was found to be the most important indicator explaining social development intensity, whereas the other two proximity indicators had a significant impact at certain temporal interval. In combination with scale effects, spatial dependency (correlation) was shown to play a key role that should be carefully taken into consideration in any relevant environmental study. Overall, the

  5. Assessing air quality impacts of managed lanes.

    Science.gov (United States)

    2010-12-01

    Impacts on transit bus performance and air quality were investigated for a case study high-occupancy / toll (HOT) lane project on a corridor of I-95 near Miami. Trends in air pollutant concentration monitoring data in the study area first were analyz...

  6. Towards a political economy of roads

    DEFF Research Database (Denmark)

    Wilson, Fiona

    2004-01-01

    by the state and the mobility practices of Andean indigenous/rural society. While a location 'off the beaten track' could be a source of autonomy in the past, the article outlines reasons why people in post-conflict, neo-liberal Peru now dedicate much time and effort to road-building, even though this may...... potentially lead to loss of land, community control and greater impoverishment....

  7. The evaluation of high occupancy vehicle lanes on Sun Yat-Sen freeway in Taiwan

    Energy Technology Data Exchange (ETDEWEB)

    Jou, R.C. [National Chi Nan Univ., Nantou, Taiwan (China). Dept. of Civil Engineering; Weng, M.C. [Ministry of Transportation and Communications, Taiwan (China); Chen, C.C. [National Central Univ., Taiwan (China)

    2005-06-30

    Travel demand in Taiwan, particularly intercity trips, has changed in response to the significant increase in domestic trade and economic activities. Most of Taiwan's population lives and works along the western corridor because there is a mountain range running north-south along the eastern coast. The existing transportation system includes highways, freeways, rail and aviation. The average travel time from Taipei to Koahsiung by the Sun Yat-Sen freeway can vary from 4 to 8 hours or more on weekends and holidays. The current capacity of the freeway is insufficient to accommodate the increasing travel demand. Many traffic management strategies such as ramp metering control, no tolls, and no tolls for high occupancy vehicles (HOV) have been proposed to alleviate traffic congestion. The government plans to reallocate one inner lane as an HOV lane in each direction at all times. However, this would require a preference survey to assess the drivers' decisions to use these HOV lanes at all times on the highway. In this study, 2 types of latent attributes, perceptions and attitudes were defined to analyze their effects on travelers' choice of HOV lanes. Revealed preference and stated preference data were collected and considered simultaneously to fully utilize the strength of each type. Travelers' decisions were found to be a function of socio-economic attributes, travel characteristics and perceptions of alternatives. A model system was developed to comprise a discrete choice model and the latent variable model's structural and measurement equations. It was concluded that the preferred choice was for the HOV lane to be used toll-free, by vehicles with 4 or more passengers, in which the HOV lane is separated from regular lanes with a guardrail. 8 tabs.

  8. Benefit-cost analysis of lane departure warning and roll stability control in commercial vehicles.

    Science.gov (United States)

    Medina-Flintsch, Alejandra; Hickman, Jeffrey S; Guo, Feng; Camden, Matthew C; Hanowski, Richard J; Kwan, Quon

    2017-09-01

    This paper presents the cost benefits of two different onboard safety systems (OSS) installed on trucks as they operated during normal revenue deliveries. Using a formal economic analysis approach, the study quantified the costs and benefits associated with lane departure warning (LDW) systems and roll stability control (RSC) systems. The study used data collected from participating carriers (many of these crashes were not reported to state or Federal agencies), and the research team also reviewed each crash file to determine if the specific OSS would have mitigated or prevented the crash. The deployment of each OSS was anticipated to increase the safety of all road users, but impact different sectors of society in different ways. Benefits that were inherent in each group (e.g., industry, society) were considered, and different benefit-cost analyses (BCAs) were performed. This paper presents two BCAs: a BCA focused on the costs and benefits in the carrier industry by implementing each OSS, and a BCA that measured the societal benefits of each OSS. In addition, a BCA for a theoretical mandatory deployment option for each OSS is presented. BCA results for LDW and RSC clearly showed their benefits outweighed their costs for the carrier and society. Practical applications: Cost information is a crucial factor in purchasing decisions in carriers; similarly, regulators must consider the cost burden prior to mandating technologies. The results in this study provide carrier decision makers and regulators with information necessary to make an informed decision regarding RSC and LDW. Copyright © 2017 National Safety Council and Elsevier Ltd. All rights reserved.

  9. The Road to Rural Primary Care: A Narrative Review of Factors That Help Develop, Recruit, and Retain Rural Primary Care Physicians.

    Science.gov (United States)

    Parlier, Anna Beth; Galvin, Shelley L; Thach, Sarah; Kruidenier, David; Fagan, Ernest Blake

    2018-01-01

    To examine the literature documenting successes in recruiting and retaining rural primary care physicians. The authors conducted a narrative review of literature on individual, educational, and professional characteristics and experiences that lead to recruitment and retention of rural primary care physicians. In May 2016, they searched MEDLINE, PubMed, CINAHL, ERIC, Web of Science, Google Scholar, the Grey Literature Report, and reference lists of included studies for literature published in or after 1990 in the United States, Canada, or Australia. The authors identified 83 articles meeting inclusion criteria. They synthesized results and developed a theoretical model that proposes how the findings interact and influence rural recruitment and retention. The authors' proposed theoretical model suggests factors interact across multiple dimensions to facilitate the development of a rural physician identity. Rural upbringing, personal attributes, positive rural exposure, preparation for rural life and medicine, partner receptivity to rural living, financial incentives, integration into rural communities, and good work-life balance influence recruitment and retention. However, attending medical schools and/or residencies with a rural emphasis and participating in rural training may reflect, rather than produce, intention for rural practice. Many factors enhance rural physician identity development and influence whether physicians enter, remain in, and thrive in rural practice. To help trainees and young physicians develop the professional identity of a rural physician, multifactorial medical training approaches aimed at encouraging long-term rural practice should focus on rural-specific clinical and nonclinical competencies while providing trainees with positive rural experiences.

  10. A geometric stochastic approach based on marked point processes for road mark detection from high resolution aerial images

    Science.gov (United States)

    Tournaire, O.; Paparoditis, N.

    Road detection has been a topic of great interest in the photogrammetric and remote sensing communities since the end of the 70s. Many approaches dealing with various sensor resolutions, the nature of the scene or the wished accuracy of the extracted objects have been presented. This topic remains challenging today as the need for accurate and up-to-date data is becoming more and more important. Based on this context, we will study in this paper the road network from a particular point of view, focusing on road marks, and in particular dashed lines. Indeed, they are very useful clues, for evidence of a road, but also for tasks of a higher level. For instance, they can be used to enhance quality and to improve road databases. It is also possible to delineate the different circulation lanes, their width and functionality (speed limit, special lanes for buses or bicycles...). In this paper, we propose a new robust and accurate top-down approach for dashed line detection based on stochastic geometry. Our approach is automatic in the sense that no intervention from a human operator is necessary to initialise the algorithm or to track errors during the process. The core of our approach relies on defining geometric, radiometric and relational models for dashed lines objects. The model also has to deal with the interactions between the different objects making up a line, meaning that it introduces external knowledge taken from specifications. Our strategy is based on a stochastic method, and in particular marked point processes. Our goal is to find the objects configuration minimising an energy function made-up of a data attachment term measuring the consistency of the image with respect to the objects and a regularising term managing the relationship between neighbouring objects. To sample the energy function, we use Green algorithm's; coupled with a simulated annealing to find its minimum. Results from aerial images at various resolutions are presented showing that our

  11. What externally presented information do VRUs require when interacting with fully Automated Road Transport Systems in shared space?

    Science.gov (United States)

    Merat, Natasha; Louw, Tyron; Madigan, Ruth; Wilbrink, Marc; Schieben, Anna

    2018-03-31

    As the desire for deploying automated ("driverless") vehicles increases, there is a need to understand how they might communicate with other road users in a mixed traffic, urban, setting. In the absence of an active and responsible human controller in the driving seat, who might currently communicate with other road users in uncertain/conflicting situations, in the future, understanding a driverless car's behaviour and intentions will need to be relayed via easily comprehensible, intuitive and universally intelligible means, perhaps presented externally via new vehicle interfaces. This paper reports on the results of a questionnaire-based study, delivered to 664 participants, recruited during live demonstrations of an Automated Road Transport Systems (ARTS; SAE Level 4), in three European cities. The questionnaire sought the views of pedestrians and cyclists, focussing on whether respondents felt safe interacting with ARTS in shared space, and also what externally presented travel behaviour information from the ARTS was important to them. Results showed that most pedestrians felt safer when the ARTS were travelling in designated lanes, rather than in shared space, and the majority believed they had priority over the ARTS, in the absence of such infrastructure. Regardless of lane demarcations, all respondents highlighted the importance of receiving some communication information about the behaviour of the ARTS, with acknowledgement of their detection by the vehicle being the most important message. There were no clear patterns across the respondents, regarding preference of modality for these external messages, with cultural and infrastructural differences thought to govern responses. Generally, however, conventional signals (lights and beeps) were preferred to text-based messages and spoken words. The results suggest that until these driverless vehicles are able to provide universally comprehensible externally presented information or messages during interaction

  12. Joint road safety operations in tunnels and open roads

    Science.gov (United States)

    Adesiyun, Adewole; Avenoso, Antonio; Dionelis, Kallistratos; Cela, Liljana; Nicodème, Christophe; Goger, Thierry; Polidori, Carlo

    2017-09-01

    The objective of the ECOROADS project is to overcome the barrier established by the formal interpretation of the two Directives 2008/96/EC and 2004/54/EC, which in practice do not allow the same Road Safety Audits/Inspections to be performed inside tunnels. The projects aims at the establishment of a common enhanced approach to road infrastructure and tunnel safety management by using the concepts and criteria of the Directive 2008/96/CE on road infrastructure safety management and the results of related European Commission (EC) funded projects. ECOROADS has already implemented an analysis of national practices regarding Road Safety Inspections (RSI), two Workshops with the stakeholders, and an exchange of best practices between European tunnel experts and road safety professionals, which led to the definition of common agreed safety procedures. In the second phase of the project, different groups of experts and observers applied the above common procedures by inspecting five European road sections featuring both open roads and tunnels in Belgium, Albania, Germany, Serbia and Former Yugoslav Republic of Macedonia. This paper shows the feedback of the 5 joint safety operations and how they are being used for a set of - recommendations and guidelines for the application of the RSA and RSI concepts within the tunnel safety operations.

  13. Towards 400GBASE 4-lane Solution Using Direct Detection of MultiCAP Signal in 14 GHz Bandwidth per Lane

    DEFF Research Database (Denmark)

    Iglesias Olmedo, Miguel; Tianjian, Zuo; Jensen, Jesper Bevensee

    2013-01-01

    We report on an experimental demonstration of 102 Gbit/s transmission over a 15km single wavelength and polarization fiber link with 14GHz 3dB bandwidth. Novel multiband CAP signaling allows for a 4-lane 400GBASE long reach solution....

  14. Road Accident Prevention with Instant Emergency Warning Message Dissemination in Vehicular Ad-Hoc Network.

    Directory of Open Access Journals (Sweden)

    P Gokulakrishnan

    Full Text Available A Road Accident Prevention (RAP scheme based on Vehicular Backbone Network (VBN structure is proposed in this paper for Vehicular Ad-hoc Network (VANET. The RAP scheme attempts to prevent vehicles from highway road traffic accidents and thereby reduces death and injury rates. Once the possibility of an emergency situation (i.e. an accident is predicted in advance, instantly RAP initiates a highway road traffic accident prevention scheme. The RAP scheme constitutes the following activities: (i the Road Side Unit (RSU constructs a Prediction Report (PR based on the status of the vehicles and traffic in the highway roads, (ii the RSU generates an Emergency Warning Message (EWM based on an abnormal PR, (iii the RSU forms a VBN structure and (iv the RSU disseminates the EWM to the vehicles that holds the high Risk Factor (RF and travels in High Risk Zone (HRZ. These vehicles might reside either within the RSU's coverage area or outside RSU's coverage area (reached using VBN structure. The RAP scheme improves the performance of EWM dissemination in terms of increase in notification and decrease in end-to-end delay. The RAP scheme also reduces infrastructure cost (number of RSUs by formulating and deploying the VBN structure. The RAP scheme with VBN structure improves notification by 19 percent and end-to-end delay by 14.38 percent for a vehicle density of 160 vehicles. It is also proved from the simulation experiment that the performance of RAP scheme is promising in 4-lane highway roads.

  15. Road Accident Prevention with Instant Emergency Warning Message Dissemination in Vehicular Ad-Hoc Network.

    Science.gov (United States)

    Gokulakrishnan, P; Ganeshkumar, P

    2015-01-01

    A Road Accident Prevention (RAP) scheme based on Vehicular Backbone Network (VBN) structure is proposed in this paper for Vehicular Ad-hoc Network (VANET). The RAP scheme attempts to prevent vehicles from highway road traffic accidents and thereby reduces death and injury rates. Once the possibility of an emergency situation (i.e. an accident) is predicted in advance, instantly RAP initiates a highway road traffic accident prevention scheme. The RAP scheme constitutes the following activities: (i) the Road Side Unit (RSU) constructs a Prediction Report (PR) based on the status of the vehicles and traffic in the highway roads, (ii) the RSU generates an Emergency Warning Message (EWM) based on an abnormal PR, (iii) the RSU forms a VBN structure and (iv) the RSU disseminates the EWM to the vehicles that holds the high Risk Factor (RF) and travels in High Risk Zone (HRZ). These vehicles might reside either within the RSU's coverage area or outside RSU's coverage area (reached using VBN structure). The RAP scheme improves the performance of EWM dissemination in terms of increase in notification and decrease in end-to-end delay. The RAP scheme also reduces infrastructure cost (number of RSUs) by formulating and deploying the VBN structure. The RAP scheme with VBN structure improves notification by 19 percent and end-to-end delay by 14.38 percent for a vehicle density of 160 vehicles. It is also proved from the simulation experiment that the performance of RAP scheme is promising in 4-lane highway roads.

  16. Commentary: Status of road safety in Asia.

    Science.gov (United States)

    Wismans, Jac; Skogsmo, Ingrid; Nilsson-Ehle, Anna; Lie, Anders; Thynell, Marie; Lindberg, Gunnar

    2016-01-01

    hand, lack of good high-quality accident data should not be an excuse to postpone interventions. There are many opportunities for evidence-based transport safety improvements, including measures concerning the 5 key risk factors: speed, drunk driving, not wearing motorcycle helmets, not wearing seat belts, and not using child restraints in cars, as specified in the Decade of Action for Road Safety 2011-2020. In this commentary, a number of additional measures are proposed that are not covered in the Decade of Action Plan. These new measures include separate roads or lanes for pedestrians and cyclists; helmet wearing for e-bike riders; special attention to elderly persons in public transportation; introduction of emerging collision avoidance technologies, in particular automatic emergency braking (AEB) and alcohol locks; improved truck safety focusing on the other road user (including blind spot detection technology; underride protection at the front, rear, and side; and energy-absorbing fronts); and improvements in motorcycle safety concerning protective clothing, requirements for advanced braking systems, improved visibility of motorcycles by using daytime running lights, and better guardrails.

  17. Spatio-temporal Variations in on-road CO2 Emissions in the Los Angeles Megacity

    Directory of Open Access Journals (Sweden)

    Preeti Rao

    2017-06-01

    Full Text Available We quantify hourly on-road fossil fuel carbon dioxide (FFCO2 emissions at the road segment level for the Los Angeles (LA megacity based on observed traffic data, and characterize emission patterns across space and time. This on-road FFCO2 emissions dataset for LA (from Hestia version 1.0, based on actual traffic volume, provides emissions per vehicle kilometer travelled (VKT—an important metric for greenhouse gas (GHG reductions. We further identify emissions hotpots that can help state and local policy makers plan the most effective GHG reduction strategies. On-road vehicle traffic accounts for half of the FFCO2 emissions in LA, of which 41% is from arterials (intermediate road type. Arterials also have the largest C emissions intensity—FFCO2 per VKT—possibly from high traffic congestion and fleet composition. Non-interstate emissions hotspots (> 419 tC lane-km-1 are equally dominated by arterials and collectors (the lowest road type in terms of FFCO2 emissions though collectors have a higher VKT. These hotspots occur in densely populated areas and developed landuse classes, largely in LA (67% and Orange (18% counties, and provide specific targets for emissions reduction efforts. The estimated uncertainties for interstate, arterial and collector emissions per road length are ± 2.1, ± 0.5 and ± 18.0%, respectively. Our overall estimates compare reasonably well with other products, DARTE and FIVE but with substantial differences in spatial distribution. The method for developing this dataset is easily replicable in other urban landscapes, and represents a powerful tool for carbon cycle science and regional policy makers.

  18. Investigating Car Users’ Driving Behaviour through Speed Analysis

    Directory of Open Access Journals (Sweden)

    Laura Eboli

    2017-04-01

    Full Text Available Speed has been identified for a long time as a key risk factor in road traffic: inappropriate speeds contribute to a relevant part of traffic accidents. Many literature studies have focused on the relationship between speed and accident risk. Starting from this consideration this paper investigates traffic accident risk by analysing the travelling speeds recorded by real tests on the road. A survey was conducted to collect experimental speed values in a real context. A specific road segment, belonging to an Italian rural two-lane road, was repeatedly run by 27 drivers in order to collect the instantaneous speed values for each trajectory. Smartphone-equipped vehicles were used to record continuous speed data. The recorded data were used to calculate: the average speed, 50th and 85th percentile speed for each geometric element of the analysed road segment. The main result of the research is the classification of car users’ driving behaviour based on the speed values. By using the above mentioned ranges of speed, the classification provides three types of driving behaviour: safe, unsafe, and safe but potentially dangerous. It was found that only four drivers feature “safe” behaviour, driving in a safe manner on most of the road elements. However, the major part of drivers, even if they feature safe behaviour, could be dangerous for other drivers because they drive at very low speeds.

  19. Cellular automata model for urban road traffic flow considering pedestrian crossing street

    Science.gov (United States)

    Zhao, Han-Tao; Yang, Shuo; Chen, Xiao-Xu

    2016-11-01

    In order to analyze the effect of pedestrians' crossing street on vehicle flows, we investigated traffic characteristics of vehicles and pedestrians. Based on that, rules of lane changing, acceleration, deceleration, randomization and update are modified. Then we established two urban two-lane cellular automata models of traffic flow, one of which is about sections with non-signalized crosswalk and the other is on uncontrolled sections with pedestrians crossing street at random. MATLAB is used for numerical simulation of the different traffic conditions; meanwhile space-time diagram and relational graphs of traffic flow parameters are generated and then comparatively analyzed. Simulation results indicate that when vehicle density is lower than around 25 vehs/(km lane), pedestrians have modest impact on traffic flow, whereas when vehicle density is higher than about 60 vehs/(km lane), traffic speed and volume will decrease significantly especially on sections with non-signal-controlled crosswalk. The results illustrate that the proposed models reconstruct the traffic flow's characteristic with the situation where there are pedestrians crossing and can provide some practical reference for urban traffic management.

  20. Multifractal chaotic attractors in a system of delay-differential equations modeling road traffic.

    Science.gov (United States)

    Safonov, Leonid A.; Tomer, Elad; Strygin, Vadim V.; Ashkenazy, Yosef; Havlin, Shlomo

    2002-12-01

    We study a system of delay-differential equations modeling single-lane road traffic. The cars move in a closed circuit and the system's variables are each car's velocity and the distance to the car ahead. For low and high values of traffic density the system has a stable equilibrium solution, corresponding to the uniform flow. Gradually decreasing the density from high to intermediate values we observe a sequence of supercritical Hopf bifurcations forming multistable limit cycles, corresponding to flow regimes with periodically moving traffic jams. Using an asymptotic technique we find approximately small limit cycles born at Hopf bifurcations and numerically preform their global continuations with decreasing density. For sufficiently large delay the system passes to chaos following the Ruelle-Takens-Newhouse scenario (limit cycles-two-tori-three-tori-chaotic attractors). We find that chaotic and nonchaotic attractors coexist for the same parameter values and that chaotic attractors have a broad multifractal spectrum. (c) 2002 American Institute of Physics.

  1. Open Access!: Review of Online Statistics: An Interactive Multimedia Course of Study by David Lane

    Directory of Open Access Journals (Sweden)

    Samuel L. Tunstall

    2016-01-01

    Full Text Available David M. Lane (project leader. Online Statistics Education: An Interactive Multimedia Course of Study (http://onlinestatbook.com/ Also: David M. Lane (primary author and editor, with David Scott, Mikki Hebl, Rudy Guerra, Dan Osherson, and Heidi Zimmer. Introduction to Statistics. Online edition (http://onlinestatbook.com/Online_Statistics_Education.pdf, 694 pp. It is rare that students receive high-quality textbooks for free, but David Lane's Online Statistics: An Interactive Multimedia Course of Study permits precisely that. This review gives an overview of the many features in Lane's online textbook, including the Java Applets, the textbook itself, and the resources available for instructors. A discussion of uses of the site, as well as a comparison of the text to alternative online statistics textbooks, is included.

  2. Removing non-urban roads from the National Land Cover Database to create improved urban maps for the United States, 1992-2011

    Science.gov (United States)

    Soulard, Christopher E.; Acevedo, William; Stehman, Stephen V.

    2018-01-01

    Quantifying change in urban land provides important information to create empirical models examining the effects of human land use. Maps of developed land from the National Land Cover Database (NLCD) of the conterminous United States include rural roads in the developed land class and therefore overestimate the amount of urban land. To better map the urban class and understand how urban lands change over time, we removed rural roads and small patches of rural development from the NLCD developed class and created four wall-to-wall maps (1992, 2001, 2006, and 2011) of urban land. Removing rural roads from the NLCD developed class involved a multi-step filtering process, data fusion using geospatial road and developed land data, and manual editing. Reference data classified as urban or not urban from a stratified random sample was used to assess the accuracy of the 2001 and 2006 urban and NLCD maps. The newly created urban maps had higher overall accuracy (98.7 percent) than the NLCD maps (96.2 percent). More importantly, the urban maps resulted in lower commission error of the urban class (23 percent versus 57 percent for the NLCD in 2006) with the trade-off of slightly inflated omission error (20 percent for the urban map, 16 percent for NLCD in 2006). The removal of approximately 230,000 km2 of rural roads from the NLCD developed class resulted in maps that better characterize the urban footprint. These urban maps are more suited to modeling applications and policy decisions that rely on quantitative and spatially explicit information regarding urban lands.

  3. Effects of age and auditory and visual dual tasks on closed-road driving performance.

    Science.gov (United States)

    Chaparro, Alex; Wood, Joanne M; Carberry, Trent

    2005-08-01

    This study investigated how driving performance of young and old participants is affected by visual and auditory secondary tasks on a closed driving course. Twenty-eight participants comprising two age groups (younger, mean age = 27.3 years; older, mean age = 69.2 years) drove around a 5.1-km closed-road circuit under both single and dual task conditions. Measures of driving performance included detection and identification of road signs, detection and avoidance of large low-contrast road hazards, gap judgment, lane keeping, and time to complete the course. The dual task required participants to verbally report the sums of pairs of single-digit numbers presented through either a computer speaker (auditorily) or a dashboard-mounted monitor (visually) while driving. Participants also completed a vision and cognitive screening battery, including LogMAR visual acuity, Pelli-Robson letter contrast sensitivity, the Trails test, and the Digit Symbol Substitution (DSS) test. Drivers reported significantly fewer signs, hit more road hazards, misjudged more gaps, and increased their time to complete the course under the dual task (visual and auditory) conditions compared with the single task condition. The older participants also reported significantly fewer road signs and drove significantly more slowly than the younger participants, and this was exacerbated for the visual dual task condition. The results of the regression analysis revealed that cognitive aging (measured by the DSS and Trails test) rather than chronologic age was a better predictor of the declines seen in driving performance under dual task conditions. An overall z score was calculated, which took into account both driving and the secondary task (summing) performance under the two dual task conditions. Performance was significantly worse for the auditory dual task compared with the visual dual task, and the older participants performed significantly worse than the young subjects. These findings demonstrate

  4. Verification of road databases using multiple road models

    Science.gov (United States)

    Ziems, Marcel; Rottensteiner, Franz; Heipke, Christian

    2017-08-01

    In this paper a new approach for automatic road database verification based on remote sensing images is presented. In contrast to existing methods, the applicability of the new approach is not restricted to specific road types, context areas or geographic regions. This is achieved by combining several state-of-the-art road detection and road verification approaches that work well under different circumstances. Each one serves as an independent module representing a unique road model and a specific processing strategy. All modules provide independent solutions for the verification problem of each road object stored in the database in form of two probability distributions, the first one for the state of a database object (correct or incorrect), and a second one for the state of the underlying road model (applicable or not applicable). In accordance with the Dempster-Shafer Theory, both distributions are mapped to a new state space comprising the classes correct, incorrect and unknown. Statistical reasoning is applied to obtain the optimal state of a road object. A comparison with state-of-the-art road detection approaches using benchmark datasets shows that in general the proposed approach provides results with larger completeness. Additional experiments reveal that based on the proposed method a highly reliable semi-automatic approach for road data base verification can be designed.

  5. On-road Bicycle Pavement Markings

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — A mile by mile breakdown of the on-street bicycle pavement markings installed within the City of Pittsburgh. These include bike lanes, shared lane markings...

  6. Work zone simulator analysis : driver performance and acceptance of Missouri alternate lane shift configurations.

    Science.gov (United States)

    2017-01-13

    The objective of this project is to evaluate MoDOTs alternate lane shift sign configuration for work zones. The single sign proposed by MoDOT provides the traveler with enough information to let them know that all lanes are available to shift arou...

  7. Tire-road noise: an experimental study of tire and road design parameters

    OpenAIRE

    Bekke, Dirk; Wijnant, Ysbrand H.; Weegerink, Thijs; de Boer, Andries

    2013-01-01

    It is widely known that road traffic noise has negative influences on human health. Hence, as tire-road noise is considered to be the most dominant cause of road traffic noise above 30-50 km/h, a lot of research is performed by the two involving industries: road authorities/manufacturers and tire manufacturers. Usually, the parameters influencing exterior tire-road noise are often examined separately, whereas it is the tire-road interaction which obviously causes the actual noise. An integral...

  8. Road Maintenance Experience Using Polyurethane (PU) Foam Injection System and Geocrete Soil Stabilization as Ground Rehabilitation

    Science.gov (United States)

    Fakhar, A. M. M.; Asmaniza, A.

    2016-07-01

    There are many types of ground rehabilation and improvement that can be consider and implement in engineering construction works for soil improvement in order to prevent road profile deformation in later stage. However, when comes to road maintenance especially on operated expressways, not all method can be apply directly as it must comply to opreation's working window and lane closure basis. Key factors that considering ideal proposal for ground rehabilitation are time, cost, quality and most importantly practicality. It should provide long lifespan structure in order to reduce continuous cycle of maintenance. Thus, this paper will present two approaches for ground rehabilitation, namely Polyurethane (PU) Foam Injection System and Geocrete Soil Stabilization. The first approach is an injection system which consists two-parts chemical grout of Isocynate and Polyol when mixed together within soil structure through injection will polymerized with volume expansion. The strong expansion of grouting causes significant compression and compacting of the surrounding soil and subsequently improve ground properties and uplift sunken structure. The later is a cold in-place recyclying whereby mixture process that combines in-situ soil materials, cement, white powder (alkaline) additive and water to produce hard yet flexible and durable ground layer that act as solid foundation with improved bearing capacity. The improvement of the mechanical behaviour of soil through these two systems is investigated by an extensive testing programme which includes in-situ and laboratory test in determining properties such as strength, stiffness, compressibility, bearing capacity, differential settlement and etc.

  9. At the end of the potholed road

    DEFF Research Database (Denmark)

    Jordt Jørgensen, Nanna

    It took nearly 2 hours to drive the 60 km potholed Kenyan road from the administrative center in Laikipia North to the nearest big town by car or minibus. And much longer if riding on top of one of the heavy lorries transporting sand from dry riverbeds in the area to construction sites in town....... When young people travelled to town, they would often, when reaching the smoother part of the tarmac road, exclaim something like ‘now we have arrived in Kenya’ or ‘this is where development begins’, as if Laikipia North was not really part of the Kenyan state. The relation between pastoral communities...... proclaimed their community to be marginalized and in political opposition to the government, they also dreamed about infrastructure development and aspired to a closer incorporation in the Kenyan state and its development schemes. This paper explores the ambiguities of roads leading to rural places...

  10. Tire-road noise: an experimental study of tire and road design parameters

    NARCIS (Netherlands)

    Bekke, Dirk; Wijnant, Ysbrand H.; Weegerink, Thijs; de Boer, Andries

    2013-01-01

    It is widely known that road traffic noise has negative influences on human health. Hence, as tire-road noise is considered to be the most dominant cause of road traffic noise above 30-50 km/h, a lot of research is performed by the two involving industries: road authorities/manufacturers and tire

  11. Supply Chains and Rural Development in the Asia Pacific Region

    OpenAIRE

    Armbruster, Walter J.; Coyle, William T.

    2008-01-01

    Rapid income growth and urbanization are having profound impacts on the food system, food producers and rural areas in the developing Asia Pacific economies. Meeting the challenge of rural development will depend on better integrating rural areas with fast-growing urban areas where the composition of food demand is changing and the logistics of supply are growing more complex. Possible government options include investment in transportation infrastructure—roads, railroads and waterway—and pro...

  12. Operational performance of a congested corridor with lanes dedicated to autonomous vehicle traffic

    Directory of Open Access Journals (Sweden)

    Zachary Vander Laan

    2017-06-01

    Full Text Available This paper considers the operational performance impact of autonomous vehicles (AV on a multi-lane freeway corridor with separate lanes dedicated to AV and non-AV traffic. Autonomous vehicle behavior is modeled at the macroscopic level by modifying the fundamental diagram relating hourly traffic flow and vehicle density, a step that is justified by adjusting a parameter from Newell’s car-following model at the microscopic level and transforming back to a macroscopic representation. The model is applied to the I-95 corridor between Washington, DC and Baltimore, MD during the PM peak period, where the impact of introducing a managed AV-only lane is assessed at varying penetration rates of autonomous vehicles. The results show that the overall corridor performance metrics improve with increasing penetration rates up to 30%, 40% or 50% (depending on the underlying assumptions that govern AV behavior, after which the performance deteriorates drastically. Implications of the results are discussed in light of the per-lane and aggregated metrics, and future directions for research are proposed.

  13. Smart density: A more accurate method of measuring rural residential density for health-related research.

    Science.gov (United States)

    Owens, Peter M; Titus-Ernstoff, Linda; Gibson, Lucinda; Beach, Michael L; Beauregard, Sandy; Dalton, Madeline A

    2010-02-12

    Studies involving the built environment have typically relied on US Census data to measure residential density. However, census geographic units are often unsuited to health-related research, especially in rural areas where development is clustered and discontinuous. We evaluated the accuracy of both standard census methods and alternative GIS-based methods to measure rural density. We compared residential density (units/acre) in 335 Vermont school neighborhoods using conventional census geographic units (tract, block group and block) with two GIS buffer measures: a 1-kilometer (km) circle around the school and a 1-km circle intersected with a 100-meter (m) road-network buffer. The accuracy of each method was validated against the actual residential density for each neighborhood based on the Vermont e911 database, which provides an exact geo-location for all residential structures in the state. Standard census measures underestimate residential density in rural areas. In addition, the degree of error is inconsistent so even the relative rank of neighborhood densities varies across census measures. Census measures explain only 61% to 66% of the variation in actual residential density. In contrast, GIS buffer measures explain approximately 90% of the variation. Combining a 1-km circle with a road-network buffer provides the closest approximation of actual residential density. Residential density based on census units can mask clusters of development in rural areas and distort associations between residential density and health-related behaviors and outcomes. GIS-defined buffers, including a 1-km circle and a road-network buffer, can be used in conjunction with census data to obtain a more accurate measure of residential density.

  14. Smart density: a more accurate method of measuring rural residential density for health-related research

    Directory of Open Access Journals (Sweden)

    Gibson Lucinda

    2010-02-01

    Full Text Available Abstract Background Studies involving the built environment have typically relied on US Census data to measure residential density. However, census geographic units are often unsuited to health-related research, especially in rural areas where development is clustered and discontinuous. Objective We evaluated the accuracy of both standard census methods and alternative GIS-based methods to measure rural density. Methods We compared residential density (units/acre in 335 Vermont school neighborhoods using conventional census geographic units (tract, block group and block with two GIS buffer measures: a 1-kilometer (km circle around the school and a 1-km circle intersected with a 100-meter (m road-network buffer. The accuracy of each method was validated against the actual residential density for each neighborhood based on the Vermont e911 database, which provides an exact geo-location for all residential structures in the state. Results Standard census measures underestimate residential density in rural areas. In addition, the degree of error is inconsistent so even the relative rank of neighborhood densities varies across census measures. Census measures explain only 61% to 66% of the variation in actual residential density. In contrast, GIS buffer measures explain approximately 90% of the variation. Combining a 1-km circle with a road-network buffer provides the closest approximation of actual residential density. Conclusion Residential density based on census units can mask clusters of development in rural areas and distort associations between residential density and health-related behaviors and outcomes. GIS-defined buffers, including a 1-km circle and a road-network buffer, can be used in conjunction with census data to obtain a more accurate measure of residential density.

  15. Impact of infrastructure on rural household income and inequality in Nepal

    DEFF Research Database (Denmark)

    Charlery, Lindy Callen; Qaim, Matin; Smith-Hall, Carsten

    2016-01-01

    contributes to the literature by empirically analysing the effects of rural road construction on household income and income inequality in Nepal. Using a quasi-experimental design, a difference-in-difference approach is developed and employed to analyse household (n = 177) data before and after road...... construction. We find that the new road had a significantly positive impact on mean household income of USD 235 (28%). Contrary to expectations, we do not find an increase in income inequality. Compared to the counterfactual site, it appears that the road has rather contributed to decreasing income inequality....... The poorest households gained most from the road construction, making it a pro-poor development intervention....

  16. Quantitative analysis of pedestrian safety at uncontrolled multi-lane mid-block crosswalks in China.

    Science.gov (United States)

    Zhang, Cunbao; Zhou, Bin; Chen, Guojun; Chen, Feng

    2017-11-01

    A lot of pedestrian-vehicle crashes at mid-block crosswalks severely threaten pedestrian's safety around the world. The situations are even worse in China due to low yielding rate of vehicles at crosswalks. In order to quantitatively analyze pedestrian's safety at multi-lane mid-block crosswalks, the number of pedestrian-vehicle conflicts was utilized to evaluate pedestrian's accident risk. Five mid-block crosswalks (Wuhan, China) were videoed to collect data of traffic situation and pedestrian-vehicle conflicts, and the quantity and spatial distribution of pedestrian-vehicle conflicts at multi-lane mid-block crosswalk were analyzed according to lane-based post-encroachment time(LPET). Statistical results indicate that conflicts are mainly concentrated in lane3 and lane6. Percentage of conflict of each lane numbered from 1 to 6 respectively are 4.1%, 13.1%, 19.8%, 8.4%, 19.0%, 28.1%. Conflict rate under different crossing strategies are also counted. Moreover, an order probit (OP) model of pedestrian-vehicle conflict analysis (PVCA) was built to find out the contributions corresponding to those factors (such as traffic volume, vehicle speed, pedestrian crossing behavior, pedestrian refuge, etc.) to pedestrian-vehicle conflicts. The results show that: pedestrian refuge have positive effects on pedestrian safety; on the other hand, high vehicle speed, high traffic volume, rolling gap crossing pattern, and larger pedestrian platoon have negative effects on pedestrian safety. Based on our field observation and PVCA model, the number of conflicts will rise by 2% while the traffic volume increases 200 pcu/h; similarly, if the vehicle speed increases 5km/h, the number of conflicts will rise by 12% accordingly. The research results could be used to evaluate pedestrian safety at multi-lane mid-block crosswalks, and useful to improve pedestrian safety by means of pedestrian safety education, pedestrian refuge setting, vehicle speed limiting, and so on. Copyright © 2017

  17. Dynamic rockfall risk assessment along the SS113 coastal road (Northern Sicily)

    Science.gov (United States)

    Mastrolembo, V. Brunella; Penna, Ivanna; Voumard, Jérémie; Jaboyedoff, Michel

    2016-04-01

    rockfall risk assessment we apply a two steps approach. First, we realize an hazard estimation along the SS113 road applying a classical approach to evaluate the propagation area, so the probability of impact and storage of boulders on the road lanes. Then, we use this result as input to realize a dynamic estimation of risk for vehicles traveling on the road. Using the TSiNaHa numerical simulator we estimate the risk relative to different combinations of rockfall scenarios and traffic variables. The aim of the work is to get informations that could be used by local politicians and decision makers to take decisions both, about permanent mitigation measures and emergency actions to be taken during the alert phase or after the occurrence of a rockfall.

  18. Road grip test in Arjeplog

    OpenAIRE

    Engström, Niclas; Andrén, Henrik; Nybacka, Mikael; Fransson, Lennart; Larsson, Roland

    2008-01-01

    The Swedish road administration sees a need to improve the road grip estimation capacity for the Swedish road system. The challenge is to find methods to measure road grip fast and reliable. There where six different system types at the tests in Arjeplog, three continuous, two system measuring road grip through deceleration and one system based on GPS and accelerometers. Two system types used air craft runway tires. The other systems used either studded winter tires or friction winter tires. ...

  19. Renewable energy for rural development in Ethiopia: the case for new energy policies and institutional reform

    Energy Technology Data Exchange (ETDEWEB)

    Wolde-Ghiorgis, W. [Addis Ababa Univ., Dept. of Electrical and Computer Engineering, Addis Ababa (Ethiopia)

    2002-09-01

    This article argues the case for introducing new energy policies in Ethiopia that will ensure energy initiatives for rural development meet the desired expectations. A review of the rural energy sector in Ethiopia is presented. Rural communities have for centuries relied solely on traditional biomass energy sources, human and animal power. In addition, sample findings show that the basic stock of traditional biomass energy resources is dwindling fast for two reasons: one, due to rapid population growth; and two, due to the absence of energy substitutes for traditional energy sources. Renewable energy technologies and other modern energy technologies are almost non-existent. In terms of budgetary allocation, rural energy development has not received a fair share of public investment in comparison to education, rural road construction and health. A key policy recommendation made in this article is the need for commitment from concerned authorities to the use of renewables for spurring rural development. This could be done through increasing the budget allocation to rural energy, which is currently negligible. Other policy recommendations include the modification of existing institutional frameworks for rural energy delivery, and the design and implementation of appropriate rural energy initiatives suitable for productive activities and sustainable development. (Author)

  20. Microscopic modeling of multi-lane highway traffic flow

    Science.gov (United States)

    Hodas, Nathan O.; Jagota, Anand

    2003-12-01

    We discuss a microscopic model for the study of multi-lane highway traffic flow dynamics. Each car experiences a force resulting from a combination of the desire of the driver to attain a certain velocity, aerodynamic drag, and change of the force due to car-car interactions. The model also includes multi-lane simulation capability and the ability to add and remove obstructions. We implement the model via a Java applet, which is used to simulate traffic jam formation, the effect of bottlenecks on traffic flow, and the existence of light, medium, and heavy traffic flow. The simulations also provide insight into how the properties of individual cars result in macroscopic behavior. Because the investigation of emergent characteristics is so common in physics, the study of traffic in this manner sheds new light on how the micro-to-macro transition works in general.

  1. Study on driver`s stress in lane-change maneuver. Evaluation and analysis of heat rate change; Shasen henkoji no untensha no kinchodo kaiseki. Shinpaku hendo no gen`in bunrui to sono hyoka

    Energy Technology Data Exchange (ETDEWEB)

    Sumida, K [Mitsubishi Motors Corp., Tokyo (Japan); Chikamori, S; Shimizu, Y [Seikei University, Tokyo (Japan)

    1997-10-01

    We measured the changes of heart rate in order to analyze the drivers` stress while they tried high speed lane-change on the stationary driving simulator. We concluded that the reasons of the chances were mainly dependent on the following two items. (1) mental pressure caused by the coming task of lane-change, (2) mental disturbance by the task to keep the vehicle inside the lane. By using the mental pressure and disturbance, we could evaluate the stability of the vehicles in lane-change maneuver. 3 refs., 11 figs.

  2. Impact of left lane truck restriction strategies on multilane highways in Louisiana : a literature review.

    Science.gov (United States)

    2009-04-01

    Truck lane restriction strategies (TLRS) are a means of managing truck traffic on highways by prohibiting trucks from using certain lanes to minimize interaction between trucks and other vehicles. The purpose of this study is to review the literature...

  3. Trends of child undernutrition in rural Ecuadorian communities with differential access to roads, 2004-2013.

    Science.gov (United States)

    Lopez, Velma K; Dombecki, Carolyn; Trostle, James; Mogrovejo, Patricia; Castro Morillo, Nancy; Cevallos, William; Goldstick, Jason; Jones, Andrew D; Eisenberg, Joseph N S

    2018-02-07

    Road access can influence protective and risk factors associated with nutrition by affecting various social and biological processes. In northern coastal Ecuador, the construction of new roads created a remoteness gradient among villages, providing a unique opportunity to examine the impact of roads on child nutritional outcomes 10 years after the road was built. Anthropometric and haemoglobin measurements were collected from 2,350 children road access. Logistic generalized estimating equation models assessed the longitudinal association between village remoteness and prevalence of stunting, wasting, underweight, overweight, obesity, and anaemia. We examined the influence of socio-economic characteristics on the pathway between remoteness and nutrition by comparing model results with and without household-level socio-economic covariates. Remoteness was associated with stunting (OR = 0.43, 95% CI [0.30, 0.63]) and anaemia (OR = 0.56, 95% CI [0.44, 0.70]). Over time, the prevalence of stunting was generally decreasing but remained higher in villages closer to the road compared to those farther away. Obesity increased (0.5% to 3%) over time; wasting was high (6%) but stable during the study period. Wealth and education partially explained the better nutritional outcomes in remote vs. road villages more than a decade after some communities gained road access. Establishing the extent to which these patterns persist requires additional years of observation. © 2018 John Wiley & Sons Ltd.

  4. Assessing air quality impacts of managed lanes : summary.

    Science.gov (United States)

    2010-01-01

    Researchers at the National Center for Transit Research, University of South Florida, recently studied a segment of I-95 between Ft. Lauderdale and Miami to investigate the impacts of high-occupancy/toll (HOT) lanes on air quality. The project simula...

  5. Modelos de perfil de velocidad para evaluación de consistencia del trazado en carreteras de la provincia de Villa Clara, Cuba Speed profile models for evaluation of design consistency in road of the province of Villa Clara, Cuba

    Directory of Open Access Journals (Sweden)

    René A. García Depestre

    2012-08-01

    Full Text Available Entre los aspectos relativos a la carretera que influyen en la accidentalidad, tiene un gran peso el diseño geométrico, internacionalmente el método más empleado para la evaluación del diseño es a partir de la consistencia del trazado con modelos de perfil de velocidades de operación. Cuba no cuenta con modelos propios que consideren las características de las carreteras y los conductores, por lo que es necesario desarrollar modelos de predicción de velocidades para la evaluación de la consistencia del trazado. El desarrollo de modelos de predicción del perfil de velocidades de operación para diferentes condiciones de alineación en carreteras rurales de dos carriles en el contexto de Cuba, se efectúa a partir de características geométricas y velocidades puntuales, con análisis estadístico de las principales variables que relacionan la velocidad con el diseño. Una vez desarrollados los modelos, se aplican a un tramo de carretera declarado como tramo de concentración de accidentes (TCA de la provincia de Villa Clara localizada en la región central de Cuba, los resultados obtenidos confirman la validez de los modelos desarrollados para determinar los perfiles de velocidad de operación y de esta forma, evaluar la consistencia del trazado, con el objetivo de detectar los lugares de mayores dificultades con relación al trazado.Among the aspects that influence road accidents, geometric design is the most relevant. The most used method for evaluating the design all over the world is based on the design consistency with speed profile models of operation. Cuba does not have proprietary models that consider the characteristics of the roads and drivers, so it is necessary to develop predictive models for the evaluation of design consistency. The development of operating speed profile prediction models for different alignment conditions on rural roads with two lanes in the context of Cuba is made from the geometric characteristics and

  6. Non-lane-discipline-based car-following model under honk environment

    Science.gov (United States)

    Rong, Ying; Wen, Huiying

    2018-04-01

    This study proposed a non-lane-discipline-based car-following model by synthetically considering the visual angles and the timid/aggressive characteristics of drivers under honk environment. We firstly derived the neutral stability condition by the linear stability theory. It showed that the parameters related to visual angles and driving characteristics of drivers under honk environment all have significant impact on the stability of non-lane-discipline traffic flow. For better understanding the inner mechanism among these factors, we further analyzed how each parameter affects the traffic flow and gained further insight into how the visual angles information influences other parameters and then influences the non-lane-discipline traffic flow under honk environment. And the results showed that the other aspects such as driving characteristics of drivers or honk effect are all interacted with the "Visual-Angle Factor". And the effect of visual angle is not just to say simply it has larger stable region or not as the existing studies. Finally, to verify the proposed model, we carried out the numerical simulation under the periodic boundary condition. And the results of numerical simulation are agreed well with the theoretical findings.

  7. Lead Concentrations in Soils and Some Wild Plant Species Along Two Busy Roads in Pakistan.

    Science.gov (United States)

    Khalid, Noreen; Hussain, Mumtaz; Young, Hillary S; Ashraf, Muhammad; Hameed, Mansoor; Ahmad, Rashid

    2018-02-01

    This study assessed the level of Pb in soil and five wild plant species (Calotropis procera, Datura alba, Parthenium hysterophorus, Cenchrus ciliaris and Ricinus communis) during all the four seasons. Two busy roads varying in age and traffic volume were selected i.e., Faisalabad-Sargodha road (FSR) and Pindi Bhattian to Lillah (M-2) in the Punjab, Pakistan. Results showed raised levels of Pb in both plants and soil samples along both roads. The range of Pb concentration in plants was 0.08-3.98 and 1.95-4.74 mg kg - 1 for soil. Higher Pb contamination was recorded along FSR road as compared to M-2. Among seasons, the higher Pb concentration was found during summer, probably due to very high temperature. Among all the plants studied, Calotropis procera accumulated the highest level (3.98 mg kg - 1 dry wt.) of Pb; Thus, it can be used as good biomonitor/phytoremediator at Pb contaminated areas.

  8. Saturation flow mathematical model based on multiple combinations of lane groups

    Energy Technology Data Exchange (ETDEWEB)

    Racila, L.

    2016-07-01

    The ideal value of the traffic stream that can pass through an intersection is known as the saturation flow rate per hour on vehicle green time. The saturation flow is important in the understanding of the traffic light cycle and from there the understanding the Level of Service. The paper wishes to evaluate through a series of applied mathematical methods the effect of different lane grouping and critical lane group concept on the saturation flow rate. The importance of this method is that it creates a base for a signalized intersections timing plan. (Author)

  9. Making Bengali Brick Lane: claiming and contesting space in East London.

    Science.gov (United States)

    Alexander, Claire

    2011-06-01

    Based on a recent empirical project on 'the Bengal diaspora', the paper explores the construction and contestation of meanings around the iconic East London street, Brick Lane. Taking the 2006 protests around the film Brick Lane as its starting point, the paper draws on original interviews conducted in 2008 with a range of Bengali community representatives, to examine the narratives of space, community and belonging that emerge around the idea of Brick Lane as the 'cultural heartland' of the British Bangladeshi community. By exploring the representation, production and contestation of 'social space' through everyday practices, the paper engages with and contests the representation of minority ethnic 'communities' in the context of contemporary multicultural London and examines the process of 'claiming' and 'making' space in East London. In so doing, the paper contributes to a critical tradition that challenges essentialising and pathologizing accounts of ethnic communities and racialized spaces, or that places them outside of broader social and historical processes - redolent, for example, in contemporary discussions about 'parallel lives' or 'the clash of civilizations'. By contrast, this paper views social space as made through movement and narration, with a particular emphasis on the social agency of local Bengali inhabitants and the multiple meanings that emerge from within this 'imagined community'. However, rather than simply stressing the unfinished and processual nature of spatial meanings, the paper insists on the historical, embodied and affective dimensions of such meaning making, and a reckoning with the broader social and political landscape within which such meanings take shape. The focus on Brick Lane provides an empirically rich, geographically and historically located lens through which to explore the complex role of ethnicity as a marker of social space and of spatial practices of resistance and identity. By exploring Bengali Brick Lane through

  10. The effect of concurrent bandwidth feedback on learning the lane-keeping task in a driving simulator.

    Science.gov (United States)

    de Groot, Stefan; de Winter, Joost C F; López García, José Manuel; Mulder, Max; Wieringa, Peter A

    2011-02-01

    The aim of this study was to investigate whether concurrent bandwidth feedback improves learning of the lane-keeping task in a driving simulator. Previous research suggests that bandwidth feedback improves learning and that off-target feedback is superior to on-target feedback. This study aimed to extend these findings for the lane-keeping task. Participants without a driver's license drove five 8-min lane-keeping sessions in a driver training simulator: three practice sessions, an immediate retention session, and a delayed retention session I day later. There were four experimental groups (n=15 per group): (a) on-target, receiving seat vibrations when the center of the car was within 0.5 m of the lane center; (b) off-target, receiving seat vibrations when the center of the car was more than 0.5 m away from the lane center; (c) control, receiving no vibrations; and (d) realistic, receiving seat vibrations depending on engine speed. During retention, all groups were provided with the realistic vibrations. During practice, on-target and off-target groups had better lane-keeping performance than the nonaugmented groups, but this difference diminished in the retention phase. Furthermore, during late practice and retention, the off-target group outperformed the on-target group.The off-target group had a higher rate of steering reversal and higher steering entropy than the nonaugmented groups, whereas no clear group differences were found regarding mean speed, mental workload, or self-reported measures. Off-target feedback is superior to on-target feedback for learning the lane-keeping task. This research provides knowledge to researchers and designers of training systems about the value of feedback in simulator-based training of vehicular control.

  11. On the origin of the dust lane in the active radio galaxies

    International Nuclear Information System (INIS)

    Morita, Kazuhiko; Sakashita, Shiro

    1979-01-01

    A simple explosion model leading to the extragalactic extended radio sources is developed to understand the origin of the dust lane seen in the active radio galaxies. The point explosion in a spheroid with inhomogeneous density distribution is investigated by taking account of the cooling effect induced by radiative energy loss. It is suggested that the morphological relation between the dust lane and double radio sources is well explained on the basis of explosion model. (author)

  12. Driver assistance system for lane departure avoidance by steering and differential braking

    OpenAIRE

    MINOIU-ENACHE, N; MAMMAR, S; GLASER, S; LUSETTI, B

    2010-01-01

    Lane departure avoidance systems assist actively the driver during inattention or drowsiness and increase driving safety. Most of the lane departure avoidance systems use for the lateral control of the vehicle in closed loop a DC motor similar to the electrical powered steering (EPS) assistance. Important difficulties and limits of this approach are the shared control with the driver on the steering wheel and the vehicle handling at limits. In this paper a combined lateral control using a DC ...

  13. Economic development and road traffic fatalities in two neighbouring African nations

    Directory of Open Access Journals (Sweden)

    Douglas J. Wiebe

    2016-06-01

    Conclusion: Road crash fatalities increased in recent decades in both Zambia and Botswana. But the rapid economic development in Botswana over this time period appears to have driven proportionate road traffic fatality increases. There are opportunities for newly emerging economies such as Zambia, Angola, and others to learn from the Botswana experience. Evidence-based investments in road safety interventions should be concomitant with economic development.

  14. Modeling merging behavior at lane drops : [tech transfer summary].

    Science.gov (United States)

    2015-02-01

    A better understanding of the merging behavior of drivers will lead : to the development of better lane-drop traffic-control plans and : strategies, which will provide better guidance to drivers for safer : merging.

  15. An observational study of consumer use of fast-food restaurant drive-through lanes: implications for menu labelling policy.

    Science.gov (United States)

    Roberto, Christina A; Hoffnagle, Elena; Bragg, Marie A; Brownell, Kelly D

    2010-11-01

    Some versions of restaurant menu labelling legislation do not require energy information to be posted on menus for drive-through lanes. The present study was designed to quantify the number of customers who purchase fast food through drive-in windows as a means of informing legislative labelling efforts. This was an observational study. The study took place at two McDonald's and Burger King restaurants, and single Dairy Queen, Kentucky Fried Chicken, Taco Bell and Wendy's restaurants. The number of customers entering the chain restaurants and purchasing food via the drive-through lane were recorded. A total of 3549 patrons were observed. The percentage of customers who made their purchases at drive-throughs was fifty-seven. The overall average (57 %) is likely a conservative estimate because some fast-food restaurants have late-night hours when only the drive-throughs are open. Since nearly six in ten customers purchase food via the drive-through lanes, menu labelling legislation should mandate the inclusion of menu labels on drive-through menu boards to maximise the impact of this public health intervention.

  16. Integrating transit with road pricing projects.

    Science.gov (United States)

    2013-06-01

    This study examined various levels of the treatment of public transportation in conjunction with the implementation of : managed lane highway projects. It details the ranges of transit investments identified in and associated with managed : lanes tha...

  17. The impact of road salt runoff on methanogens and other lacustrine prokaryotes

    Science.gov (United States)

    Sprague, E.; Dupuis, D.; Koretsky, C.; Docherty, K. M.

    2017-12-01

    Road salt deicers are widely used in regions that experience icy winters. The resulting saline runoff can negatively impact freshwater lake ecosystems. Saline runoff can cause density stratification, resulting in persistently anoxic hypolimnia. This may result in a shift in the structure of the hypolimnetic prokaryotic community, with potential increases in anaerobic and halotolerant taxa. Specifically, anoxia creates a habitat suitable for the proliferation of obligately anaerobic Archaeal methanogens. As a result, more persistent and expanded anoxic zones due to road salt runoff have the potential to increase hypolimnetic methane concentrations. If a portion of this methane is released to the atmosphere, it could be a currently uncharacterized contributor to atmospheric greenhouse gas emissions. This study examines two urban, eutrophic lakes with significant road salt influx and one rural, eutrophic lake with little road salt influx. All three lakes are located in southwest Michigan. Samples were taken from the water column at every meter at the deepest part of each lake, with a sample from the sediment-water interface, in May, August, and November 2016 and February 2017. The V4 and V5 hypervariable regions of the 16S rRNA gene in Bacteria and Archaea were amplified and sequenced using an Illumina MiSeq approach. Abundance of the mcrA gene, a marker for Archaeal methyl coenzyme A reductase, was quantified using qPCR. Water column methane levels, sediment methane production, water surface methane flux and a suite of supporting geochemical parameters were measured to determine changes in redox stratification in each lake and across seasons. Results indicate significant changes in the 16S rRNA-based community associated with depth, season, salinity and lake. Cyanobacteria, Actinobacteria, and Proteobacteria were among the phyla with the highest overall relative abundance. Sediment samples had more copies of the mcrA gene than the water column samples. In most

  18. Operational performance management of priced facilities

    Science.gov (United States)

    2011-03-01

    The Texas Department of Transportation and its agency partners have implemented various forms of lane management and pricing over the past three decades, including HOV lanes, managed lanes, and toll roads. As more of these complex transportation faci...

  19. Two Aspects of the Rural-Urban Divide and Educational Stratification in China: A Trajectory Analysis.

    Science.gov (United States)

    Hao, Lingxin; Hu, Alfred; Lo, Jamie

    2014-08-01

    Contextualized in China's social change of the past half-century, this paper develops the notion of dichotomous inequality to conceptualize the two aspects of China's rural-urban divide in educational inequality-the household registration system ( hukou ) assigns people to a top-bottom hierarchy, and the rural-urban schooling system institutionalizes unequal resource distribution and diverse school mission. Based on this conceptualization, we formulate a Chinese version of the maximally maintained inequality (MMI) hypothesis. We capitalize on individual educational history data from the China General Social Survey (CGSS) 2008 and conduct a trajectory analysis using the generalized mixture modeling to estimate the differential effects of the two aspects of rural-urban divide on educational inequality in China. Findings indicate that (1) the sorting mechanism of the rural hukou places rural- hukou people in the very bottom of educational stratification, (2) the penalty of attending rural pre-tertiary school increases with educational stages, and (3) there is a cumulative disadvantage of rural hukou and rural school. Overall, our findings attest to the Chinese-version MMI and the behind principle of inequality reproduction.

  20. 77 FR 76929 - Final Flood Elevation Determinations

    Science.gov (United States)

    2012-12-31

    ... Rocky Shelby County. Hollow Lane. Approximately 416 feet +464 upstream of Rocky Hollow Lane. Ivy Branch... of County Road 280 (Old Highway 280). Lee Branch Approximately 884 feet +553 City of Birmingham, City... +608 upstream of Hugh Daniel Drive. Lee Brook At the upstream side of +417 City of Helena. County Road...

  1. Explaining the road accident risk: weather effects.

    Science.gov (United States)

    Bergel-Hayat, Ruth; Debbarh, Mohammed; Antoniou, Constantinos; Yannis, George

    2013-11-01

    This research aims to highlight the link between weather conditions and road accident risk at an aggregate level and on a monthly basis, in order to improve road safety monitoring at a national level. It is based on some case studies carried out in Work Package 7 on "Data analysis and synthesis" of the EU-FP6 project "SafetyNet-Building the European Road Safety Observatory", which illustrate the use of weather variables for analysing changes in the number of road injury accidents. Time series analysis models with explanatory variables that measure the weather quantitatively were used and applied to aggregate datasets of injury accidents for France, the Netherlands and the Athens region, over periods of more than 20 years. The main results reveal significant correlations on a monthly basis between weather variables and the aggregate number of injury accidents, but the magnitude and even the sign of these correlations vary according to the type of road (motorways, rural roads or urban roads). Moreover, in the case of the interurban network in France, it appears that the rainfall effect is mainly direct on motorways--exposure being unchanged, and partly indirect on main roads--as a result of changes in exposure. Additional results obtained on a daily basis for the Athens region indicate that capturing the within-the-month variability of the weather variables and including it in a monthly model highlights the effects of extreme weather. Such findings are consistent with previous results obtained for France using a similar approach, with the exception of the negative correlation between precipitation and the number of injury accidents found for the Athens region, which is further investigated. The outlook for the approach and its added value are discussed in the conclusion. Copyright © 2013. Published by Elsevier Ltd.

  2. Comparative analysis of dynamic pricing strategies for managed lanes.

    Science.gov (United States)

    2015-06-01

    The objective of this research is to investigate and compare the performances of different : dynamic pricing strategies for managed lanes facilities. These pricing strategies include real-time : traffic responsive methods, as well as refund options a...

  3. eRoads

    DEFF Research Database (Denmark)

    Connolly, David

    vehicles enable more renewable electricity to be integrated onto the electricity grid. This is particularly evident in 2050, since the price of fossil fuels increases while the price of renewable electricity and batteries decreases. Finally, the electric road scenarios can facilitate more reductions......This study compares electric roads with oil (petrol and diesel) and battery electric vehicles, using Denmark as a case study. Electric roads can reduce the cost of electric vehicles by supplying them with electricity directly from the road rather than via a battery for long-distance journeys....... In this paper, an electric road scenario is compared to both an oil and battery electric vehicle scenario using the 2010 Danish energy system, but for two sets of costs: one set based on historical costs from the year 2010 and one based on projected costs for the year 2050. The results indicate that electric...

  4. Simulator Evaluation of Drivers’ Performance on Rural Highways in relation to Drivers’ Visual Attention Demands

    Directory of Open Access Journals (Sweden)

    Yaqin Qin

    2015-01-01

    Full Text Available Aim of the study is to investigate, by means of a driving simulator experiment, drivers’ performance in terms of lateral position, speed, deceleration, steering angle, and breaking times on a divided two-lane rural highway in relation to drivers’ visual attention (VD. In the experiment, the virtual scene of twenty different geometric alignment sections without traffic and the VD testing were designed. Twenty-three experienced drivers with the calibration of attention capacity participated in a 30 km drive in an interactive fixed-base simulator. Each participant was required to drive with the controlled speed of 60 km/h along the central lane as repeating random number and was evaluated on VD and driving performances. Three different data analysis techniques were used: (a statistical tests and hypothesis test of curvature change rate (CCR of the geometric alignments, visual attention demands, and driving performance data, (b correlation analysis of VD, CCRs, and driving behaviors, and (c regression analysis of the VD and CCRs. Results have showed that the driving performance can be effectively influenced by the highway alignment and a prediction model built in this study can evaluate the drivers’ visual attention demands before the highway constructed. The interactions among VD, driving behavior, and CCRs were also found.

  5. Factors shaping the HIV-competence of two primary schools in rural Zimbabwe

    DEFF Research Database (Denmark)

    Campbell, Catherine; Andersen, Louise; Mutsikiwa, Alice

    2015-01-01

    We present multi-method case studies of two Zimbabwean primary schools - one rural and one small-town. The rural school scored higher than the small-town school on measures of child well-being and school attendance by HIV-affected children. The small-town school had superior facilities, more...... teachers with higher morale, more specialist HIV/AIDS activities, and an explicit religious ethos. The relatively impoverished rural school was located in a more cohesive community with a more critically conscious, dynamic and networking headmaster. The current emphasis on HIV/AIDS-related teacher training...

  6. Coordination locale et optimisation distribuée du trafic de véhicules autonomes dans un réseau routier

    OpenAIRE

    Tlig , Mohamed

    2015-01-01

    In this thesis, we focus on traffic coordination and optimization in road intersections, while accounting for intelligent autonomous vehicles. This thesis is organized in two parts. The first part focuses on the problem of sharing a one-lane road between two opposite flows of vehicles. The state of the art shows few studies addressing this issue. We propose two reactive coordination approaches that minimize vehicle delays and measure their performances statistically through simulations. The s...

  7. 77 FR 8253 - Notice of Proposed Settlement Agreement and Opportunity for Public Comment: Hidden Lane Landfill...

    Science.gov (United States)

    2012-02-14

    ... ENVIRONMENTAL PROTECTION AGENCY [FRL-9631-3] Notice of Proposed Settlement Agreement and Opportunity for Public Comment: Hidden Lane Landfill Superfund Site ACTION: Notice. SUMMARY: In accordance... (``DOJ'') on behalf of EPA, in connection with the Hidden Lane Landfill Superfund Site, Sterling, Loudoun...

  8. Road Safety Related Behaviours of Romanian Young People

    Directory of Open Access Journals (Sweden)

    Lucia Maria LOTREAN

    2010-03-01

    Full Text Available Aim: The objective of this study was to assess the behaviors with risk for road traffic injuries among Romanian young people. Material and Method: Self-administered questionnaires were completed by the study sample consisting of 1598 junior high school students, senior high school students and university students aged 11-24 years from both urban and rural areas of two counties (Cluj and Hunedora of Romania. Results: The results show that around 80% of the junior high school students and more than 90% of the senior high school students and university students who go by bike do not wear helmets or use them rarely when they are cycling. Seatbelts are used more frequently than the helmets, but still more than one third of the junior high school students and senior high school students and a quarter of the university students do not use seatbelts or use them rarely. In the month previous the survey around one quarter of the students travelled in a car whose driver used alcohol before driving. Moreover, 15% of the university students who drove recognized that, at least once during their life, they did this after they used alcohol. Conclusions: The results indicate that comprehensive actions must be developed in order to prevent road traffic injuries among Romanian young people. They must include educational programs for youngsters and parents as well as adoption and enforcement of legislative measures and technical actions, which promote road safety.

  9. Geospatial Estimates of Road Salt Usage Across a Gradient of Urbanizing Watersheds in Southern Ontario:Thesis for Masters in Spatial Analysis (MSA)

    Science.gov (United States)

    Giberson, G. K.; Oswald, C.

    2015-12-01

    In areas affected by snow, chloride (Cl) salts are widely used as a de-icing agent to improve road conditions. While the improvement in road safety is indisputable, there are environmental consequences to local aquatic ecosystems. In many waterways, Cl concentrations have been increasing since the early 1990s, often exceeding national water quality guidelines. To determine the quantity of Cl that is accumulating in urban and urbanizing watersheds, accurate estimates of road salt usage at the watershed-scale are needed. The complex jurisdictional control over road salt application in southern Ontario lends itself to a geospatial approach for calculating Cl inputs to improve the accuracy of watershed-scale Cl mass balance estimates. This study will develop a geospatial protocol for combining information on road salt applications and road network areas to refine watershed-scale Cl inputs, as well as assess spatiotemporal patterns in road salt application across the southern Ontario study region. The overall objective of this project is to use geospatial methods (predominantly ArcGIS) to develop high-accuracy estimates of road salt usage in urbanizing watersheds in southern Ontario. Specifically, the aims will be to map and summarize the types and areas ("lane-lengths") of roadways in each watershed that have road salt applied to them, to determine the most appropriate source(s) of road salt usage data for each watershed, taking into consideration multiple levels of jurisdiction (e.g. municipal, regional, provincial), to calculate and summarize sub-watershed and watershed-scale road salt usage estimates for multiple years, and to analyze intra-watershed spatiotemporal patterns of road salt usage, especially focusing on impervious surfaces. These analyses will recommend areas of concern exacerbated by high-levels of road salt distribution; recommendations around modifying on-the-ground operations will be the next step in helping to correct these issues.

  10. Two Aspects of the Rural-Urban Divide and Educational Stratification in China: A Trajectory Analysis*

    Science.gov (United States)

    Hao, Lingxin; Hu, Alfred; Lo, Jamie

    2015-01-01

    Contextualized in China’s social change of the past half-century, this paper develops the notion of dichotomous inequality to conceptualize the two aspects of China’s rural-urban divide in educational inequality—the household registration system (hukou) assigns people to a top-bottom hierarchy, and the rural-urban schooling system institutionalizes unequal resource distribution and diverse school mission. Based on this conceptualization, we formulate a Chinese version of the maximally maintained inequality (MMI) hypothesis. We capitalize on individual educational history data from the China General Social Survey (CGSS) 2008 and conduct a trajectory analysis using the generalized mixture modeling to estimate the differential effects of the two aspects of rural-urban divide on educational inequality in China. Findings indicate that (1) the sorting mechanism of the rural hukou places rural-hukou people in the very bottom of educational stratification, (2) the penalty of attending rural pre-tertiary school increases with educational stages, and (3) there is a cumulative disadvantage of rural hukou and rural school. Overall, our findings attest to the Chinese-version MMI and the behind principle of inequality reproduction. PMID:26166835

  11. The impact of road improvements on road safety and related characteristics

    OpenAIRE

    Francis John Gichaga

    2017-01-01

    This paper presents the historical and cultural background relating to road improvement and road safety characteristics in Kenya, a developing country in East Africa. Some who come from low-developed areas of developing countries often take time to comprehend the modern transportation infrastructure, especially roads, and have difficulty assimilating and customizing the same to their culturally tailored modes. This paper discusses two case studies: one on the socio-economic impact followin...

  12. Heterogeneous traffic flow modelling using second-order macroscopic continuum model

    Science.gov (United States)

    Mohan, Ranju; Ramadurai, Gitakrishnan

    2017-01-01

    Modelling heterogeneous traffic flow lacking in lane discipline is one of the emerging research areas in the past few years. The two main challenges in modelling are: capturing the effect of varying size of vehicles, and the lack in lane discipline, both of which together lead to the 'gap filling' behaviour of vehicles. The same section length of the road can be occupied by different types of vehicles at the same time, and the conventional measure of traffic concentration, density (vehicles per lane per unit length), is not a good measure for heterogeneous traffic modelling. First aim of this paper is to have a parsimonious model of heterogeneous traffic that can capture the unique phenomena of gap filling. Second aim is to emphasize the suitability of higher-order models for modelling heterogeneous traffic. Third, the paper aims to suggest area occupancy as concentration measure of heterogeneous traffic lacking in lane discipline. The above mentioned two main challenges of heterogeneous traffic flow are addressed by extending an existing second-order continuum model of traffic flow, using area occupancy for traffic concentration instead of density. The extended model is calibrated and validated with field data from an arterial road in Chennai city, and the results are compared with those from few existing generalized multi-class models.

  13. Perceptions and Beliefs of Rural High School Coordinators in Costa Rica

    Directory of Open Access Journals (Sweden)

    Mario Segura Castillo

    2014-05-01

    Full Text Available Costa Rican rural settings include indigenous populations and groups in scattered areas that require considering issues such as language and culture, among others, to achieve an appropriate curriculum development. The National Institute of Statistics and Census (INEC defines rurality based on the existence or lack of public services such as roads, communication, utilities, formation of the household, and participation in agricultural activities, among others. This research seeks to interpret the perceptions and beliefs of rural high school principals in Costa Rica, regarding technical and administrative conditions in compliance with the objectives for which the institutions were created. This is a longitudinal qualitative study, since data was taken from two workshops, one in 2010 with 49 rural high school coordinators and another one in 2012 with 205 participants including principals and teaching staff. Information was analyzed using an open-question questionnaire and a Venn diagram. Seventeen rural high schools were visited, and students, teachers, and parents from 45 rural high schools were interviewed during 2011 and 2012. It is concluded that there is still no real integration between the socio productive, personal and social areas with the academic area; therefore, teachers in the academic area should be trained in vocational aspects such as entrepreneurship, cooperativism, business management, as well as counsoling, physical education, arts, and music to trully meet the objectives for which rural high schools were created.

  14. Multiple job holding in rural villages and the Chinese road to development.

    Science.gov (United States)

    van der Ploeg, Jan Douwe; Jingzhong, Ye

    2010-01-01

    This paper examines some of the interrelations that exist between rural China's peasant economy and the wider economy in which it is embedded. In doing so it focuses on the circular flows that link town and countryside. Multiple job holding is strategic in this respect. The paper draws on research undertaken in a peasant village in Hebei Province. The research highlights some remarkable differences that exist between development processes in China and in other developing countries and traces these back to a combination of an enlightened rural policy and the strong linkages that exist between rural China and its urban "global factory".

  15. Roads may act as barriers to flying insects: species composition of bees and wasps differs on two sides of a large highway

    Directory of Open Access Journals (Sweden)

    Petter Andersson

    2017-07-01

    Full Text Available Roads may act as barriers to animal movements, but direct barrier effects on insects have rarely been studied. In this study we collected data on bees and wasps along two sides of a large road in Sweden using yellow pan traps. We then analyzed if the species composition differed between the two sides of the road; first for the whole community, and then only for the smallest species (which typically are poorer dispersers. As a complement, we analyzed if different vegetation variables differed between the two sides of the road, as this may also affect differences in species composition. Finally, we analyzed if species richness and abundance in general differed between the two sides and how these two response variables were explained by the vegetation variables. There was a significant difference in species composition between the eastern and the western side of the road when analyzing the whole community, and this relationship became even stronger when the largest species were excluded. The vegetation variables did not strongly differ between the two sides, and there was no difference in species richness and abundance of bees and wasps either. Abundance was, however, explained by the number of flowering plants in the surroundings of the trap. Even though using a rather limited data set, our results indicate that large roads may act as barriers on the movement of bees and wasps, especially for small species with poor dispersal ability. On the other hand, road verges may be important habitat for many species, which leads to a potential conflict that is important to consider in the planning of green infrastructure.

  16. EVALUATING THE CONTRIBUTION OF PHYSICAL PARAMETERS ON THE SAFETY OF UNSIGNALIZED INTERSECTIONS

    Directory of Open Access Journals (Sweden)

    A. AHMED

    2015-05-01

    Full Text Available Safety of any particular Road way facility cannot be attributed to set of parameters specific to a certain domain. Unsignalized intersections are no exceptions, thus, making them an important area of study. This paper presents the results of the analysis of four parameters, namely road width, traffic control, lane marking and landuse; and their sub-class on the safety of unsignalized intersections. The raw accident data was obtained from MIROS (Malaysian Institute of Road Safety Research. It was then reduced for descriptive analysis. Hypothesis testing was performed to assess the significance of all parameters and severity analysis was done to accomplish micro scale examination of each sub-class. The results show that landuse and lane marking are statistically significant. They are important variables to predict accidents whereas traffic control and road width are not significant. Intersections located in city with single line lane marking having no control and major road width greater than 9 meters were found to have the highest severity indices.

  17. The effect of varying levels of vehicle automation on drivers' lane changing behaviour.

    Science.gov (United States)

    Madigan, Ruth; Louw, Tyron; Merat, Natasha

    2018-01-01

    Much of the Human Factors research into vehicle automation has focused on driver responses to critical scenarios where a crash might occur. However, there is less knowledge about the effects of vehicle automation on drivers' behaviour during non-critical take-over situations, such as driver-initiated lane-changing or overtaking. The current driving simulator study, conducted as part of the EC-funded AdaptIVe project, addresses this issue. It uses a within-subjects design to compare drivers' lane-changing behaviour in conventional manual driving, partially automated driving (PAD) and conditionally automated driving (CAD). In PAD, drivers were required to re-take control from an automated driving system in order to overtake a slow moving vehicle, while in CAD, the driver used the indicator lever to initiate a system-performed overtaking manoeuvre. Results showed that while drivers' acceptance of both the PAD and CAD systems was high, they generally preferred CAD. A comparison of overtaking positions showed that drivers initiated overtaking manoeuvres slightly later in PAD than in manual driving or CAD. In addition, when compared to conventional driving, drivers had higher deviations in lane positioning and speed, along with higher lateral accelerations during lane changes following PAD. These results indicate that even in situations which are not time-critical, drivers' vehicle control after automation is degraded compared to conventional driving.

  18. The effect of varying levels of vehicle automation on drivers’ lane changing behaviour

    Science.gov (United States)

    Louw, Tyron; Merat, Natasha

    2018-01-01

    Much of the Human Factors research into vehicle automation has focused on driver responses to critical scenarios where a crash might occur. However, there is less knowledge about the effects of vehicle automation on drivers’ behaviour during non-critical take-over situations, such as driver-initiated lane-changing or overtaking. The current driving simulator study, conducted as part of the EC-funded AdaptIVe project, addresses this issue. It uses a within-subjects design to compare drivers’ lane-changing behaviour in conventional manual driving, partially automated driving (PAD) and conditionally automated driving (CAD). In PAD, drivers were required to re-take control from an automated driving system in order to overtake a slow moving vehicle, while in CAD, the driver used the indicator lever to initiate a system-performed overtaking manoeuvre. Results showed that while drivers’ acceptance of both the PAD and CAD systems was high, they generally preferred CAD. A comparison of overtaking positions showed that drivers initiated overtaking manoeuvres slightly later in PAD than in manual driving or CAD. In addition, when compared to conventional driving, drivers had higher deviations in lane positioning and speed, along with higher lateral accelerations during lane changes following PAD. These results indicate that even in situations which are not time-critical, drivers’ vehicle control after automation is degraded compared to conventional driving. PMID:29466402

  19. The effect of varying levels of vehicle automation on drivers' lane changing behaviour.

    Directory of Open Access Journals (Sweden)

    Ruth Madigan

    Full Text Available Much of the Human Factors research into vehicle automation has focused on driver responses to critical scenarios where a crash might occur. However, there is less knowledge about the effects of vehicle automation on drivers' behaviour during non-critical take-over situations, such as driver-initiated lane-changing or overtaking. The current driving simulator study, conducted as part of the EC-funded AdaptIVe project, addresses this issue. It uses a within-subjects design to compare drivers' lane-changing behaviour in conventional manual driving, partially automated driving (PAD and conditionally automated driving (CAD. In PAD, drivers were required to re-take control from an automated driving system in order to overtake a slow moving vehicle, while in CAD, the driver used the indicator lever to initiate a system-performed overtaking manoeuvre. Results showed that while drivers' acceptance of both the PAD and CAD systems was high, they generally preferred CAD. A comparison of overtaking positions showed that drivers initiated overtaking manoeuvres slightly later in PAD than in manual driving or CAD. In addition, when compared to conventional driving, drivers had higher deviations in lane positioning and speed, along with higher lateral accelerations during lane changes following PAD. These results indicate that even in situations which are not time-critical, drivers' vehicle control after automation is degraded compared to conventional driving.

  20. Micro-Study of the Evolution of Rural Settlement Patterns and Their Spatial Association with Water and Land Resources: A Case Study of Shandan County, China

    Directory of Open Access Journals (Sweden)

    Libang Ma

    2017-12-01

    Full Text Available The balance between population and water and land resources is an important part of regional sustainable development. It is also significant for the ecological civilization in China and can help solve the Three Rural Issues (agriculture, countryside and farmers in China. The Silk Road Economic Belt and Maritime Silk Road in twenty-first Century Strategy have brought new opportunities for the Hexi Corridor, which is facing challenges in the sustainable development of rural settlements. In this paper, we analyzed the temporal-spatial differentiation of rural settlement patterns in Shandan County of Hexi Corridor and studied the spatial association between rural settlements and water-land resources. Results show that the total area of rural settlement patches (CA, the number of rural settlement patches (NP, the mean patch area (MPS, the maximum patch areas (MAXP, the minimum patch areas (MINP and the density of rural settlement patches (PD changed more rapidly from 1998 to 2008 than from 2008 to 2015. In the second period, the indices mentioned before did not change significantly. The kernel density of rural settlements is basically consistent in three periods. Rural settlements mainly distribute along major roads and the hydrographic network and the kernel density of rural settlements decreases in the direction away from these roads and the hydrographic network. In addition, rural settlements in Shandan County are densely distributed in some regions and sparsely distributed in other regions. The dispersion degree of rural settlements increased from 1998 to 2008 and tended to be stable after 2008. These lead to the dispersion, hollowing and chaos of rural settlements in Shandan County. The spatial distribution of rural settlements in Shandan County is closely related to that of cultivated land and the hydrographic network. Our results might provide a theoretical basis for the reasonable utilization of water and land resources in Shandan County

  1. Design of a Multi-Sensor Cooperation Travel Environment Perception System for Autonomous Vehicle

    Directory of Open Access Journals (Sweden)

    Liang Zhang

    2012-09-01

    Full Text Available This paper describes the environment perception system designed for intelligent vehicle SmartV-II, which won the 2010 Future Challenge. This system utilizes the cooperation of multiple lasers and cameras to realize several necessary functions of autonomous navigation: road curb detection, lane detection and traffic sign recognition. Multiple single scan lasers are integrated to detect the road curb based on Z-variance method. Vision based lane detection is realized by two scans method combining with image model. Haar-like feature based method is applied for traffic sign detection and SURF matching method is used for sign classification. The results of experiments validate the effectiveness of the proposed algorithms and the whole system.

  2. Design of a Multi-Sensor Cooperation Travel Environment Perception System for Autonomous Vehicle

    Science.gov (United States)

    Chen, Long; Li, Qingquan; Li, Ming; Zhang, Liang; Mao, Qingzhou

    2012-01-01

    This paper describes the environment perception system designed for intelligent vehicle SmartV-II, which won the 2010 Future Challenge. This system utilizes the cooperation of multiple lasers and cameras to realize several necessary functions of autonomous navigation: road curb detection, lane detection and traffic sign recognition. Multiple single scan lasers are integrated to detect the road curb based on Z-variance method. Vision based lane detection is realized by two scans method combining with image model. Haar-like feature based method is applied for traffic sign detection and SURF matching method is used for sign classification. The results of experiments validate the effectiveness of the proposed algorithms and the whole system.

  3. A New Lane Departure Warning Algorithm Considering the Driver’s Behavior Characteristics

    Directory of Open Access Journals (Sweden)

    Lun Hui Xu

    2015-01-01

    Full Text Available In order to meet the driving safety warning required for different driver types and situations, a new lane departure warning (LDW algorithm was proposed. Its adaptability is much better through setting the different thresholds of time to lane crossing (TLC using fuzzy control method for driver with different driving behaviors in different lanes and different vehicle movements. To ensure the accuracy of computation of TLC under the different actual driving scenarios, the algorithm was established based on vehicle kinematics and advanced mathematics compared to other ways of computation of TLC. On this basis, a LDW strategy determining driver's intentions was presented by introducing identifying vehicle movements. Finally, a vast quantity of the real vehicle experiments was given to demonstrate the effectiveness of the proposed LDW algorithm. The results of the tests show that the algorithm can decrease false alarm rate effectively because of distinguishing from unconscious by real-time vehicle movements, and promote the adaptability to the driver behavior characteristics, so it has favorable driver acceptance and strong intelligence.

  4. Variability of Black Carbon and Ultrafine Particle Concentration on Urban Bike Routes in a Mid-Sized City in the Po Valley (Northern Italy

    Directory of Open Access Journals (Sweden)

    Giovanni Lonati

    2017-02-01

    Full Text Available Cyclists might experience increased air pollution exposure, due to the proximity to traffic, and higher intake, due to their active travel mode and higher ventilation. Several local factors, like meteorology, road and traffic features, and bike lanes features, affect cyclists’ exposure to traffic-related pollutants. This paper investigates the concentration levels and the effect of the features of the bike lanes on cyclists’ exposure to airborne ultrafine particulate matter (UFP and black carbon (BC in the mid-sized city of Piacenza, located in the middle of the Po Valley, Northern Italy. Monitoring campaigns were performed by means of portable instruments along different urban bike routes with bike lanes, characterized by different distances from the traffic source (on-road cycle lane, separated cycle lane, green cycle path, during morning (9:00 am–10:00 am and evening (17:30 pm–18:30 pm workday rush hours in both cold and warm seasons. The proximity to traffic significantly affected cyclists’ exposure to UFP and BC: exposure concentrations measured for the separated lane and for the green path were 1–2 times and 2–4 times lower than for the on-road lane. Concurrent measurements showed that exposure concentrations to PM10, PM2.5, and PM1 were not influenced by traffic proximity, without any significant variation between on-road cycle lane, separated lane, or green cycle path. Thus, for the location of this study PM mass-based metrics were not able to capture local scale concentration gradients in the urban area as a consequence of the rather high urban and regional background that hides the contribution of local scale sources, such as road traffic. The impact of route choice on cyclists’ exposure to UFPs and BC during commuting trips back and forth from a residential area to the train station has been also estimated through a probabilistic approach through an iterative Monte Carlo technique, based on the measured data. Compared

  5. The influence of economic incentives linked to road safety indicators on accidents: the case of toll concessions in Spain.

    Science.gov (United States)

    Rangel, Thais; Vassallo, José Manuel; Herraiz, Israel

    2013-10-01

    The goal of this paper is to evaluate whether the incentives incorporated in toll highway concession contracts in order to encourage private operators to adopt measures to reduce accidents are actually effective at improving safety. To this end, we implemented negative binomial regression models using information about highway characteristics and accident data from toll highway concessions in Spain from 2007 to 2009. Our results show that even though road safety is highly influenced by variables that are not managed by the contractor, such as the annual average daily traffic (AADT), the percentage of heavy vehicles on the highway, number of lanes, number of intersections and average speed; the implementation of these incentives has a positive influence on the reduction of accidents and injuries. Consequently, this measure seems to be an effective way of improving safety performance in road networks. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Análisis de consistencia de caminos bidireccionales usando mediciones continuas de velocidad de operación obtenidas con GPS Two-lane rural highways consistency analysis using continuous operating speed measurements obtained with GPS

    Directory of Open Access Journals (Sweden)

    Tomás Echaveguren

    2012-08-01

    Full Text Available El análisis de consistencia permite evaluar la seguridad en caminos en base a la velocidad. Existen diversos modelos velocidad - geometría para elementos aislados de una carretera, que se utilizan para evaluar la consistencia de elementos aislados del trazado de una carretera. Por ejemplo curvas horizontales simples o en curvas de inflexión en "S".Los modelos de análisis de consistencia agregados, permiten evaluar segmentos largos de trazado, por lo que necesitan perfiles de velocidad continuos. En este caso, los modelos y mediciones puntuales de velocidad no son adecuados. Actualmente, la tecnología de posicionamiento satelital es una manera eficiente de construir perfiles de velocidad en largas distancias del trazado, siendo particularment útil para aplicar el método de Polus. Este trabajo estudia el modelo de análisis de consistencia de Polus usando perfiles continuos de velocidad. Primero se discute dicho modelo, para luego presentar la obtención y tratamiento de datos de velocidad usando modelos y mediciones directas. El método se aplicó a 5 casos de estudio en los cual se midió en terreno la velocidad y geometría con un GPS partir del cual se obtuvieron perfiles directos y teóricos de velocidad .Los datos fueron procesados con el filtro de Kalman y suavizados con el método LOESS, para luego evaluar la consistencia de cada ruta. Se concluyó que el método de Polus y los perfiles contínuos de velocidad medidos permiten obtener una calificación de segmentos largos del trazado, pero se debe segmentar adecuadamente cada trazado para evitar sub/sobre estimaciones de consistencia.Consistency assessment permits to study road safety regarded to speed. There exist several speed-geometry models that assessed isolated components of roads, which are used for consistency assessment of single elements of roads. For instance, single horizontal curves or reverse curves. Aggregated consistency assessment models, permit to assess long

  7. [Prevention of road accidents in the road haulage field].

    Science.gov (United States)

    Rosso, G L; Zanelli, R; Corino, P; Bruno, S

    2007-01-01

    Every year many traffic accidents with fatal outcomes occur in our Country. According to the recent indications of the European Agency for Safety and Health at Work, the Piedmont region has financed the plan: Prevention of road accidents in the road haulage field. The aims of the plan are to stimulate transport companies to the target of road safety and to improve and enforce sanitary surveillance, in order to improve the safety on road haulage and to prevent traffic injuries. the plan foresees, over a period of two years, a few encounters with all the interested parties (companies, police forces, labour unions etc). During those encounters we have to give a questionnaire for evaluating the companies' knowledge about the problem and we have to choose a common plan with the aim of improving road safety. The Piedmont regional plan recalls the need to increase the attention to numerous and diversified hazards for safety on road haulage. It also imposes the choice of measures that include: risk assessment, health education, technical and environmental prevention, sanitary surveillance and clinical interventions (diagnosis and rehabilitation of occupational accidents).

  8. Trend road safety measures : international course on transportation and road engineering in developing countries. Two-year postgraduate Diploma and M.Sc. programme.

    NARCIS (Netherlands)

    1991-01-01

    This course focuses mainly on traffic and transport in developing countries, and deals primarily with matters of infrastructure. Road safety and road safety problems are closely related to the construction and operation of the road network. (See also C 1341 - C1346).

  9. Lane-Level Vehicle Trajectory Reckoning for Cooperative Vehicle-Infrastructure System

    Directory of Open Access Journals (Sweden)

    Yinsong Wang

    2012-01-01

    Full Text Available This paper presents a lane-level positioning method by trajectory reckoning without Global Positioning System (GPS equipment in the environment of Cooperative Vehicle-Infrastructure System (CVIS. Firstly, the accuracy requirements of vehicle position in CVIS applications and the applicability of GPS positioning methods were analyzed. Then, a trajectory reckoning method based on speed and steering data from vehicle’s Control Area Network (CAN and roadside calibration facilities was proposed, which consists of three critical models, including real-time estimation of steering angle and vehicle direction, vehicle movement reckoning, and wireless calibration. Finally, the proposed method was validated through simulation and field tests under a variety of traffic conditions. Results show that the accuracy of the reckoned vehicle position can reach the lane level and match the requirements of common CVIS applications.

  10. Vehicle-based road dust emission measurement (III):. effect of speed, traffic volume, location, and season on PM 10 road dust emissions in the Treasure Valley, ID

    Science.gov (United States)

    Etyemezian, V.; Kuhns, H.; Gillies, J.; Chow, J.; Hendrickson, K.; McGown, M.; Pitchford, M.

    The testing re-entrained aerosol kinetic emissions from roads (TRAKER) road dust measurement system was used to survey more than 400 km of paved roads in southwestern Idaho during 3-week sampling campaigns in winter and summer, 2001. Each data point, consisting of a 1-s measurement of particle light scattering sampled behind the front tire, was associated with a link (section of road) in the traffic demand model network for the Treasure Valley, ID. Each link was in turn associated with a number of characteristics including posted speed limit, vehicle kilometers traveled (vkt), road class (local/residential, collector, arterial, and interstate), county, and land use (urban vs. rural). Overall, the TRAKER-based emission factors based on location, setting, season, and speed spanned a narrow range from 3.6 to 8.0 g/vkt. Emission factors were higher in winter compared to summer, higher in urban areas compared to rural, and lower for roads with fast travel speeds compared to slower roads. The inherent covariance between traffic volume and traffic speed obscured the assessment of the effect of traffic volume on emission potentials. Distance-based emission factors expressed in grams per kilometer traveled (g/vkt) for roads with low travel speeds (˜11 m/s residential roads) compared to those with high travel speeds (˜25 m/s interstates) were higher (5.2 vs. 3.0 g/vkt in summer and 5.9 vs. 4.9 g/vkt in winter). However, emission potentials which characterize the amount of suspendable material on a road were substantially higher on roads with low travel speeds (0.71 vs. 0.13 g/vkt/(m/s) in summer and 0.78 vs. 0.21 g/vkt/(m/s) in winter). This suggested that while high speed roads are much cleaner (factor of 5.4 in summer), on a vehicle kilometer traveled basis, emissions from high and low speed roads are of the same order. Emission inventories based on the TRAKER method, silt loadings obtained during the field study, and US EPA's AP-42 default values of silt loading were

  11. Evaluating lane-by-lane gap-out based signal control for isolated intersection under stop-line, single and multiple advance detection systems

    Directory of Open Access Journals (Sweden)

    Chandan Keerthi Kancharla

    2016-12-01

    Full Text Available In isolated intersection’s actuated signal control, inductive loop detector layout plays a crucial role in providingthe vehicle information to the signal controller. Based on vehicle actuations at the detector, the green time is extended till a pre-defined threshold gap-out occurs. The Federal Highway Administration (FHWA proposed various guidelines for detec-tor layouts on low-speed and high-speed approaches. This paper proposes single and multiple advance detection schemes for low-speed traffic movements, that utilizes vehicle actuations from advance detectors located upstream of the stop-line, which are able to detect spill-back queues. The proposed detection schemes operate with actuated signal control based on lane-by-lane gap-out criteria. The performance of the proposed schemes is compared with FHWA’s stop-line and single advance detection schemes in the VISSIM simulation tool. Results have shown that the proposed single advance detection schemes showed improved performance in reducing travel time delay and average number of stops per vehicle under low volumes while the multiple advance detection scheme performed well under high volumes.

  12. Teaching "The Children of Willesden Lane." [DVD Series

    Science.gov (United States)

    Annenberg Media, 2006

    2006-01-01

    This unique set of multimedia resources for middle and high school teachers of history, literature, social studies, and the arts, provides background, lessons, and ideas for studying and discussing the book "The Children of Willesden Lane" (2002). This book is based on the true story of Lisa Jura, a young girl who escaped Nazi persecution, as told…

  13. An index for estimating the potential metal pollution contribution to atmospheric particulate matter from road dust in Beijing.

    Science.gov (United States)

    Zhao, Hongtao; Shao, Yaping; Yin, Chengqing; Jiang, Yan; Li, Xuyong

    2016-04-15

    The resuspension of road dust from street surfaces could be a big contributor to atmospheric particulate pollution in the rapid urbanization context in the world. However, to date what its potential contribution to the spatial pattern is little known. Here we developed an innovative index model called the road dust index (RIatmospheric suspended particles. The factors were ranked and weighted based on road dust characteristics (the amounts, grain sizes, and mobilities of the road dust, and the concentrations and toxicities of metals in the road dust). We then applied the RIatmospheric suspended particles. The results demonstrated that the road dust in urban areas has higher potential risk of metal to atmospheric particles than that in rural areas. The RIatmospheric suspended particles and for controlling atmospheric particulate pollution caused by road dust emissions. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. An examination of the environmental, driver and vehicle factors associated with the serious and fatal crashes of older rural drivers.

    Science.gov (United States)

    Thompson, J P; Baldock, M R J; Mathias, J L; Wundersitz, L N

    2013-01-01

    Motor vehicle crashes involving rural drivers aged 75 years and over are more than twice as likely to result in a serious or fatal injury as those involving their urban counterparts. The current study examined some of the reasons for this using a database of police-reported crashes (2004-2008) to identify the environmental (lighting, road and weather conditions, road layout, road surface, speed limit), driver (driver error, crash type), and vehicle (vehicle age) factors that are associated with the crashes of older rural drivers. It also determined whether these same factors are associated with an increased likelihood of serious or fatal injury in younger drivers for whom frailty does not contribute to the resulting injury severity. A number of environmental (i.e., undivided, unsealed, curved and inclined roads, and areas with a speed limit of 100km/h or greater) and driver (i.e., collision with a fixed object and rolling over) factors were more frequent in the crashes of older rural drivers and additionally associated with increased injury severity in younger drivers. Moreover, when these environmental factors were entered into a logistic regression model to predict whether older drivers who were involved in crashes did or did not sustain a serious or fatal injury, it was found that each factor independently increased the likelihood of a serious or fatal injury. Changes, such as the provision of divided and sealed roads, greater protection from fixed roadside objects, and reduced speed limits, appear to be indicated in order to improve the safety of the rural driving environment for drivers of all ages. Additionally, older rural drivers should be encouraged to reduce their exposure to these risky circumstances. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Household, Personal and Environmental Correlates of Rural Elderly’s Cycling Activity: Evidence from Zhongshan Metropolitan Area, China

    Directory of Open Access Journals (Sweden)

    Yi Zhang

    2014-06-01

    Full Text Available Cycling is an important form of active transport and physical activity to provide substantial health benefits to the elderly. Among voluminous physical activity-related literature, few studies have investigated the correlates of active transport of the rural elderly in China. This study was the first attempt to investigate the impact of the household, personal, and environmental attributes on rural elderly’s cycling activity with data collected in 102 rural neighborhoods of Zhongshan Metropolitan Area, China. The negative binomial regression models suggest that, all else being equal, living in a neighborhood with low proportion of elderly population (over 60, abundant bike lanes, and a compact urban form related to high density and mixed development, are associated with the increase of frequency and duration of the rural elderly’s cycling trips. The models also detect that attitude towards cycling and household bicycle and motorized vehicle ownership are strongly related to cycling trips of the rural elderly in Zhongshan. The findings provide insights for transportation and public health agencies, practitioners, and researchers into the effective design of interventions from the prospective of attitudes, social and built environment on health promotion of the rural elderly in China.

  16. Road dust emissions from paved roads measured using different mobile systems.

    Science.gov (United States)

    Pirjola, Liisa; Johansson, Christer; Kupiainen, Kaarle; Stojiljkovic, Ana; Karlsson, Hans; Hussein, Tareq

    2010-12-01

    Very few real-world measurements of road dust suspension have been performed to date. This study compares two different techniques (referred to as Sniffer and Emma) to measure road dust emissions. The main differences between the systems are the construction of the inlet, different instruments for recording particulate matter (PM) levels, and different loads on the wheel axes (the weight of Sniffer was much higher than that of Emma). Both systems showed substantial small-scale variations of emission levels along the road, likely depending on-road surface conditions. The variations observed correlated quite well, and the discrepancies are likely a result of variations in dust load on the road surface perpendicular to the driving direction that cause variations in the measurements depending on slightly different paths driven by the two vehicles. Both systems showed a substantial influence on the emission levels depending on the type of tire used. The summer tire showed much lower suspension than the winter tires (one nonstudded and one studded). However, the relative importance of the nonstudded versus studded tire was rather different. For the ratio of studded/nonstudded, Emma shows higher values on all road sections compared with Sniffer. Both techniques showed increased emission levels with increasing vehicle speed. When the speed increased from 50 to 80 km hr(-1), the relative concentrations increased by 30-170% depending on the tire type and dust load. However, for road sections that were very dirty, Sniffer showed a much higher relative increase in the emission level with the nonstudded tire. Sniffer's absolute concentrations were mostly higher than Emma's. Possible reasons for the differences are discussed in the paper. Both systems can be used for studying relative road dust emissions and for designing air quality management strategies.

  17. Microscopic origin and macroscopic implications of lane formation in mixtures of oppositely-driven particles

    Science.gov (United States)

    Whitelam, Stephen

    Colloidal particles of two types, driven in opposite directions, can segregate into lanes. I will describe some results on this phenomenon obtained by simple physical arguments and computer simulations. Laning results from rectification of diffusion on the scale of a particle diameter: oppositely-driven particles must, in the time taken to encounter each other in the direction of the drive, diffuse in the perpendicular direction by about one particle diameter. This geometric constraint implies that the diffusion constant of a particle, in the presence of those of the opposite type, grows approximately linearly with Peclet number, a prediction confirmed by our numerics. Such environment-dependent diffusion is statistically similar to an effective interparticle attraction; consistent with this observation, we find that oppositely-driven colloids display features characteristic of the simplest model system possessing both interparticle attractions and persistent motion, the driven Ising lattice gas. Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.

  18. Mobile assessment of on-road air pollution and its sources along the East-West Highway in Bhutan

    Science.gov (United States)

    Wangchuk, Tenzin; Knibbs, Luke D.; He, Congrong; Morawska, Lidia

    2015-10-01

    Human exposures in transportation microenvironments are poorly represented by ambient stationary monitoring. A number of on-road studies using vehicle-based mobile monitoring have been conducted to address this. Most previous studies were conducted on urban roads in developed countries where the primary emission source was vehicles. Few studies have examined on-road pollution in developing countries in urban settings. Currently, no study has been conducted for roadways in rural environments where a substantial proportion of the population live. This study aimed to characterize on-road air quality on the East-West Highway (EWH) in Bhutan and identify its principal sources. We conducted six mobile measurements of PM10, particle number (PN) count and CO along the entire 570 km length of the EWH. We divided the EWH into five segments, R1-R5, taking the road length between two district towns as a single road segment. The pollutant concentrations varied widely along the different road segments, with the highest concentrations for R5 compared with other road segments (PM10 = 149 μg/m3, PN = 5.74 × 104 particles/cm-3, CO = 0.19 ppm), which is the final segment of the road to the capital. Apart from vehicle emissions, the dominant sources were road works, unpaved roads and roadside combustion activities. Overall, the highest contributions above the background levels were made by unpaved roads for PM10 (6 times background), and vehicle emissions for PN and CO (5 and 15 times background, respectively). Notwithstanding the differences in instrumentation used and particle size range measured, the current study showed lower PN concentrations compared with similar on-road studies. However, concentrations were still high enough that commuters, road maintenance workers and residents living along the EWH, were potentially exposed to elevated pollutant concentrations from combustion and non-combustion sources. Future studies should focus on assessing the dispersion patterns of

  19. A telecommunications journey rural health network.

    Science.gov (United States)

    Moore, Joe

    2012-01-01

    Utilizing a multi-gigabit statewide fiber healthcare network, Radiology Consultants of Iowa (RCI) set out to provide instantaneous service to their rural, critical access, hospital partners. RCIs idea was to assemble a collection of technologies and services that would even out workflow, reduce time on the road, and provide superior service. These technologies included PACS, voice recognition enabled dictation, HL7 interface technology, an imaging system for digitizing paper and prior films, and modern communication networks. The Iowa Rural Health Telecommunication Project was undertaken to form a system that all critical access hospitals would participate in, allowing RCI radiologists the efficiency of "any image, anywhere, anytime".

  20. DIVIDED ATTENTION IN EXPERIENCED YOUNG AND OLDER DRIVERS - LANE TRACKING AND VISUAL ANALYSIS IN A DYNAMIC DRIVING SIMULATOR

    NARCIS (Netherlands)

    BROUWER, WH; WATERINK, W; VANWOLFFELAAR, PC; ROTHENGATTER, T

    1991-01-01

    A simulated driving task that required the simultaneous execution of two continuous visual tasks was administered to 12 healthy young (mean age 26.1 years) and 12 healthy older (mean age 64.4 years) experienced and currently active drivers. The first task was a compensatory lane-tracking task