Verification of road databases using multiple road models
NASA Astrophysics Data System (ADS)
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.
NASA Astrophysics Data System (ADS)
Jovanov, D.; Vollpracht, H. J.; Beles, H.; Popa, V.; Tolea, B. A.
2017-10-01
Most common road safety engineering deficiencies identified by the authors in South Eastern Europe, including Romania, have been collected together and presented in this paper as a part of road safety unbreakably connected to the safe system approach (driver-vehicle-road). In different South Eastern Europe countries Road Safety Audit (RSA), Road Safety Inspection (RSI), as well as Black Spot Management (BSM) was introduced and practical implementation experience enabled the authors to analyze the road safety problems. Typical road safety engineering deficiencies have been presented in 8 different subsections, based on PIARC (World Road Association) RSA approach. This paper presents collected common road safety problems with relevant illustrations (real pictures) with associated accident risks.
Behavior of road accidents: Structural time series approach
NASA Astrophysics Data System (ADS)
Junus, Noor Wahida Md; Ismail, Mohd Tahir; Arsad, Zainudin
2014-12-01
Road accidents become a major issue in contributing to the increasing number of deaths. Few researchers suggest that road accidents occur due to road structure and road condition. The road structure and condition may differ according to the area and volume of traffic of the location. Therefore, this paper attempts to look up the behavior of the road accidents in four main regions in Peninsular Malaysia by employing a structural time series (STS) approach. STS offers the possibility of modelling the unobserved component such as trends and seasonal component and it is allowed to vary over time. The results found that the number of road accidents is described by a different model. Perhaps, the results imply that the government, especially a policy maker should consider to implement a different approach in ways to overcome the increasing number of road accidents.
Hyder, Adnan A; Allen, Katharine A; Peters, David H; Chandran, Aruna; Bishai, David
2013-01-01
The growing burden of road traffic injuries, which kill over 1.2 million people yearly, falls mostly on low- and middle-income countries (LMICs). Despite this, evidence generation on the effectiveness of road safety interventions in LMIC settings remains scarce. This paper explores a scientific approach for evaluating road safety programmes in LMICs and introduces such a road safety multi-country initiative, the Road Safety in 10 Countries Project (RS-10). By building on existing evaluation frameworks, we develop a scientific approach for evaluating large-scale road safety programmes in LMIC settings. This also draws on '13 lessons' of large-scale programme evaluation: defining the evaluation scope; selecting study sites; maintaining objectivity; developing an impact model; utilising multiple data sources; using multiple analytic techniques; maximising external validity; ensuring an appropriate time frame; the importance of flexibility and a stepwise approach; continuous monitoring; providing feedback to implementers, policy-makers; promoting the uptake of evaluation results; and understanding evaluation costs. The use of relatively new approaches for evaluation of real-world programmes allows for the production of relevant knowledge. The RS-10 project affords an important opportunity to scientifically test these approaches for a real-world, large-scale road safety evaluation and generate new knowledge for the field of road safety.
Kalantari, Zahra; Cavalli, Marco; Cantone, Carolina; Crema, Stefano; Destouni, Georgia
2017-03-01
Climate-driven increase in the frequency of extreme hydrological events is expected to impose greater strain on the built environment and major transport infrastructure, such as roads and railways. This study develops a data-driven spatial-statistical approach to quantifying and mapping the probability of flooding at critical road-stream intersection locations, where water flow and sediment transport may accumulate and cause serious road damage. The approach is based on novel integration of key watershed and road characteristics, including also measures of sediment connectivity. The approach is concretely applied to and quantified for two specific study case examples in southwest Sweden, with documented road flooding effects of recorded extreme rainfall. The novel contributions of this study in combining a sediment connectivity account with that of soil type, land use, spatial precipitation-runoff variability and road drainage in catchments, and in extending the connectivity measure use for different types of catchments, improve the accuracy of model results for road flood probability. Copyright © 2016 Elsevier B.V. All rights reserved.
Heigl, Florian; Horvath, Kathrin; Laaha, Gregor; Zaller, Johann G
2017-06-26
Amphibians and reptiles are among the most endangered vertebrate species worldwide. However, little is known how they are affected by road-kills on tertiary roads and whether the surrounding landscape structure can explain road-kill patterns. The aim of our study was to examine the applicability of open-access remote sensing data for a large-scale citizen science approach to describe spatial patterns of road-killed amphibians and reptiles on tertiary roads. Using a citizen science app we monitored road-kills of amphibians and reptiles along 97.5 km of tertiary roads covering agricultural, municipal and interurban roads as well as cycling paths in eastern Austria over two seasons. Surrounding landscape was assessed using open access land cover classes for the region (Coordination of Information on the Environment, CORINE). Hotspot analysis was performed using kernel density estimation (KDE+). Relations between land cover classes and amphibian and reptile road-kills were analysed with conditional probabilities and general linear models (GLM). We also estimated the potential cost-efficiency of a large scale citizen science monitoring project. We recorded 180 amphibian and 72 reptile road-kills comprising eight species mainly occurring on agricultural roads. KDE+ analyses revealed a significant clustering of road-killed amphibians and reptiles, which is an important information for authorities aiming to mitigate road-kills. Overall, hotspots of amphibian and reptile road-kills were next to the land cover classes arable land, suburban areas and vineyards. Conditional probabilities and GLMs identified road-kills especially next to preferred habitats of green toad, common toad and grass snake, the most often found road-killed species. A citizen science approach appeared to be more cost-efficient than monitoring by professional researchers only when more than 400 km of road are monitored. Our findings showed that freely available remote sensing data in combination with a citizen science approach would be a cost-efficient method aiming to identify and monitor road-kill hotspots of amphibians and reptiles on a larger scale.
NASA Astrophysics Data System (ADS)
Maboudi, Mehdi; Amini, Jalal; Malihi, Shirin; Hahn, Michael
2018-04-01
Updated road network as a crucial part of the transportation database plays an important role in various applications. Thus, increasing the automation of the road extraction approaches from remote sensing images has been the subject of extensive research. In this paper, we propose an object based road extraction approach from very high resolution satellite images. Based on the object based image analysis, our approach incorporates various spatial, spectral, and textural objects' descriptors, the capabilities of the fuzzy logic system for handling the uncertainties in road modelling, and the effectiveness and suitability of ant colony algorithm for optimization of network related problems. Four VHR optical satellite images which are acquired by Worldview-2 and IKONOS satellites are used in order to evaluate the proposed approach. Evaluation of the extracted road networks shows that the average completeness, correctness, and quality of the results can reach 89%, 93% and 83% respectively, indicating that the proposed approach is applicable for urban road extraction. We also analyzed the sensitivity of our algorithm to different ant colony optimization parameter values. Comparison of the achieved results with the results of four state-of-the-art algorithms and quantifying the robustness of the fuzzy rule set demonstrate that the proposed approach is both efficient and transferable to other comparable images.
Assessing impacts of roads: application of a standard assessment protocol
Duniway, Michael C.; Herrick, Jeffrey E.
2013-01-01
Adaptive management of road networks depends on timely data that accurately reflect the impacts those systems are having on ecosystem processes and associated services. In the absence of reliable data, land managers are left with little more than observations and perceptions to support management decisions of road-associated disturbances. Roads can negatively impact the soil, hydrologic, plant, and animal processes on which virtually all ecosystem services depend. The Interpreting Indicators of Rangeland Health (IIRH) protocol is a qualitative method that has been demonstrated to be effective in characterizing impacts of roads. The goal of this study were to develop, describe, and test an approach for using IIRH to systematically evaluate road impacts across large, diverse arid and semiarid landscapes. We developed a stratified random sampling approach to plot selection based on ecological potential, road inventory data, and image interpretation of road impacts. The test application on a semiarid landscape in southern New Mexico, United States, demonstrates that the approach developed is sensitive to road impacts across a broad range of ecological sites but that not all the types of stratification were useful. Ecological site and road inventory strata accounted for significant variability in the functioning of ecological processes but stratification based on apparent impact did not. Analysis of the repeatability of IIRH applied to road plots indicates that the method is repeatable but consensus evaluations based on multiple observers should be used to minimize risk of bias. Landscape-scale analysis of impacts by roads of contrasting designs (maintained dirt or gravel roads vs. non- or infrequently maintained roads) suggests that future travel management plans for the study area should consider concentrating traffic on fewer roads that are well designed and maintained. Application of the approach by land managers will likely provide important insights into minimizing impacts of road networks on key ecosystem services.
4. APPROACH OF CARRS MILL ROAD TO THE SOUTH PORTAL ...
4. APPROACH OF CARRS MILL ROAD TO THE SOUTH PORTAL OF THE MITCHELLS MILL BRIDGE; VIEW TO NORTH. - Mitchell's Mill Bridge, Spanning Winter's Run on Carrs Mill Road, west of Bel Air, Bel Air, Harford County, MD
Charles R. Blinn; Rick Dahlamn; James A. Mattson; Michael A. Thompson
1999-01-01
Various approaches are available to minimize impacts on forest productivity during forest road building and timber harvesting activities. These approaches include a variety of practices and technologies. They include practices such as reducing road and trail development, using designated trails, and leaving slash at the stump on nutrient deficient sites. Technology...
A simulator study investigating how motorcyclists approach side-road hazards.
Crundall, Elizabeth; Stedmon, Alex W; Saikayasit, Rossukorn; Crundall, David
2013-03-01
The most common form of motorcycle collision in the UK occurs when another road user fails to give way and pulls out from a side road in front of an oncoming motorcyclist. While research has considered these collisions from the car driver's perspective, no research to date has addressed how motorcyclists approach these potential hazards. This study conducted a detailed analysis of motorcyclist speed and road position on approach to side-roads in a simulated suburban setting. Novice, Experienced and Advanced riders rode two laps of a simulated route, encountering five side-roads on each lap. On the second lap, a car emerged from the first side-road in a typical 'looked but failed to see' accident scenario. Three Experienced riders and one Novice rider collided with the hazard. The Advanced rider group adopted the safest strategy when approaching side-roads, with a lane position closer to the centre of the road and slower speeds. In contrast, Experienced riders chose faster speeds, often over the speed limit, especially when approaching junctions with good visibility. Rider behaviour at non-hazard junctions was compared between laps, to investigate if riders modified their behaviour after experiencing the hazard. Whilst all riders were generally more cautious after the hazard, the Advanced riders modified their behaviour more than the other groups after the hazard vehicle had pulled out. The results suggest that advanced training can lead to safer riding styles that are not acquired by experience alone. Copyright © 2012 Elsevier Ltd. All rights reserved.
DOT National Transportation Integrated Search
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...
Unofficial Road Building in the Amazon: Socioeconomic and Biophysical Explanations
NASA Technical Reports Server (NTRS)
Perz, Stephen G.; Caldas, Marcellus M.; Arima, Eugenio; Walker, Robert J.
2007-01-01
Roads have manifold social and environmental impacts, including regional development, social conflicts and habitat fragmentation. 'Road ecology' has emerged as an approach to evaluate the various ecological and hydrological impacts of roads. This article aims to complement road ecology by examining the socio-spatial processes of road building itself. Focusing on the Brazilian Amazon, a heavily-studied context due to forest fragmentation by roads, the authors consider non-state social actors who build 'unofficial roads' for the purpose of gaining access to natural resources to support livelihoods and community development. They examine four case studies of roads with distinct histories in order to explain the socio-spatial processes behind road building in terms of profit maximization, land tenure claims, co-operative and conflictive political ecologies, and constraints as well as opportunities afforded by the biophysical environment. The study cases illustrate the need for a multi-pronged theoretical approach to understanding road building, and call for more attention to the role of non-state actors in unofficial road construction.
Scott-Parker, B; Goode, N; Salmon, P
2015-01-01
The persistent overrepresentation of young drivers in road crashes is universally recognised. A multitude of factors influencing their behaviour and safety have been identified through methods including crash analyses, simulated and naturalistic driving studies, and self-report measures. Across the globe numerous, diverse, countermeasures have been implemented; the design of the vast majority of these has been informed by a driver-centric approach. An alternative approach gaining popularity in transport safety is the systems approach which considers not only the characteristics of the individual, but also the decisions and actions of other actors within the road transport system, along with the interactions amongst them. This paper argues that for substantial improvements to be made in young driver road safety, what has been learnt from driver-centric research needs to be integrated into a systems approach, thus providing a holistic appraisal of the young driver road safety problem. Only then will more effective opportunities and avenues for intervention be realised. Copyright © 2014 Elsevier Ltd. All rights reserved.
View of the PAVE PAWS radar from approach along Spencer ...
View of the PAVE PAWS radar from approach along Spencer Paul Road, looking northwest - Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA
Investigation of approach slab and its settlement for roads and bridges.
DOT National Transportation Integrated Search
2014-01-01
Approach slabs serve as a transitional system between an approach road and a bridge. Settlement of bridge approach slabs and their : supporting backfill has been experienced by more than ten Departments of Transportation throughout the United States....
Road profile estimation of city roads using DTPS
NASA Astrophysics Data System (ADS)
Wang, Qi; McDaniel, J. Gregory; Sun, Nian X.; Wang, Ming L.
2013-04-01
This work presents a non-destructive and non-contact acoustic sensing approach for measuring road profile of road and bridge deck with vehicles running at normal speed without stopping traffic. This approach uses an instantaneous and real-time dynamic tire pressure sensor (DTPS) that can measure dynamic response of the tire-road interaction and increases the efficiency of currently used road profile measuring systems with vehicle body-mounted profilers and axle-mounted accelerometers. In this work, a prototype of real-time DTPS system has been developed and demonstrated on a testing van at speeds from 5 to 80 miles per hour (mph). A data analysis algorithm has been developed to remove axle dynamic motions from the measured DTPS data and to find the transfer function between dynamic tire pressure change and the road profile. Field test has been performed to estimate road profiles. The road profile resolution is approximately 5 to 10 cm in width and sensitivity is 0. 3 cm for the height road surface features at driving speeds of 5 to 80 mph.
An Information Retrieval Approach for Robust Prediction of Road Surface States.
Park, Jae-Hyung; Kim, Kwanho
2017-01-28
Recently, due to the increasing importance of reducing severe vehicle accidents on roads (especially on highways), the automatic identification of road surface conditions, and the provisioning of such information to drivers in advance, have recently been gaining significant momentum as a proactive solution to decrease the number of vehicle accidents. In this paper, we firstly propose an information retrieval approach that aims to identify road surface states by combining conventional machine-learning techniques and moving average methods. Specifically, when signal information is received from a radar system, our approach attempts to estimate the current state of the road surface based on the similar instances observed previously based on utilizing a given similarity function. Next, the estimated state is then calibrated by using the recently estimated states to yield both effective and robust prediction results. To validate the performances of the proposed approach, we established a real-world experimental setting on a section of actual highway in South Korea and conducted a comparison with the conventional approaches in terms of accuracy. The experimental results show that the proposed approach successfully outperforms the previously developed methods.
An Information Retrieval Approach for Robust Prediction of Road Surface States
Park, Jae-Hyung; Kim, Kwanho
2017-01-01
Recently, due to the increasing importance of reducing severe vehicle accidents on roads (especially on highways), the automatic identification of road surface conditions, and the provisioning of such information to drivers in advance, have recently been gaining significant momentum as a proactive solution to decrease the number of vehicle accidents. In this paper, we firstly propose an information retrieval approach that aims to identify road surface states by combining conventional machine-learning techniques and moving average methods. Specifically, when signal information is received from a radar system, our approach attempts to estimate the current state of the road surface based on the similar instances observed previously based on utilizing a given similarity function. Next, the estimated state is then calibrated by using the recently estimated states to yield both effective and robust prediction results. To validate the performances of the proposed approach, we established a real-world experimental setting on a section of actual highway in South Korea and conducted a comparison with the conventional approaches in terms of accuracy. The experimental results show that the proposed approach successfully outperforms the previously developed methods. PMID:28134859
Road Maintenance in Africa: Approaches and Perspectives
NASA Astrophysics Data System (ADS)
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.
Understanding Road Usage Patterns in Urban Areas
NASA Astrophysics Data System (ADS)
Wang, Pu; Hunter, Timothy; Bayen, Alexandre M.; Schechtner, Katja; González, Marta C.
2012-12-01
In this paper, we combine the most complete record of daily mobility, based on large-scale mobile phone data, with detailed Geographic Information System (GIS) data, uncovering previously hidden patterns in urban road usage. We find that the major usage of each road segment can be traced to its own - surprisingly few - driver sources. Based on this finding we propose a network of road usage by defining a bipartite network framework, demonstrating that in contrast to traditional approaches, which define road importance solely by topological measures, the role of a road segment depends on both: its betweeness and its degree in the road usage network. Moreover, our ability to pinpoint the few driver sources contributing to the major traffic flow allows us to create a strategy that achieves a significant reduction of the travel time across the entire road system, compared to a benchmark approach.
NASA Astrophysics Data System (ADS)
Li, Y. H.; Shinohara, T.; Satoh, T.; Tachibana, K.
2016-06-01
High-definition and highly accurate road maps are necessary for the realization of automated driving, and road signs are among the most important element in the road map. Therefore, a technique is necessary which can acquire information about all kinds of road signs automatically and efficiently. Due to the continuous technical advancement of Mobile Mapping System (MMS), it has become possible to acquire large number of images and 3d point cloud efficiently with highly precise position information. In this paper, we present an automatic road sign detection and recognition approach utilizing both images and 3D point cloud acquired by MMS. The proposed approach consists of three stages: 1) detection of road signs from images based on their color and shape features using object based image analysis method, 2) filtering out of over detected candidates utilizing size and position information estimated from 3D point cloud, region of candidates and camera information, and 3) road sign recognition using template matching method after shape normalization. The effectiveness of proposed approach was evaluated by testing dataset, acquired from more than 180 km of different types of roads in Japan. The results show a very high success in detection and recognition of road signs, even under the challenging conditions such as discoloration, deformation and in spite of partial occlusions.
When Dijkstra Meets Vanishing Point: A Stereo Vision Approach for Road Detection.
Zhang, Yigong; Su, Yingna; Yang, Jian; Ponce, Jean; Kong, Hui
2018-05-01
In this paper, we propose a vanishing-point constrained Dijkstra road model for road detection in a stereo-vision paradigm. First, the stereo-camera is used to generate the u- and v-disparity maps of road image, from which the horizon can be extracted. With the horizon and ground region constraints, we can robustly locate the vanishing point of road region. Second, a weighted graph is constructed using all pixels of the image, and the detected vanishing point is treated as the source node of the graph. By computing a vanishing-point constrained Dijkstra minimum-cost map, where both disparity and gradient of gray image are used to calculate cost between two neighbor pixels, the problem of detecting road borders in image is transformed into that of finding two shortest paths that originate from the vanishing point to two pixels in the last row of image. The proposed approach has been implemented and tested over 2600 grayscale images of different road scenes in the KITTI data set. The experimental results demonstrate that this training-free approach can detect horizon, vanishing point, and road regions very accurately and robustly. It can achieve promising performance.
An approach to accidents modeling based on compounds road environments.
Fernandes, Ana; Neves, Jose
2013-04-01
The most common approach to study the influence of certain road features on accidents has been the consideration of uniform road segments characterized by a unique feature. However, when an accident is related to the road infrastructure, its cause is usually not a single characteristic but rather a complex combination of several characteristics. The main objective of this paper is to describe a methodology developed in order to consider the road as a complete environment by using compound road environments, overcoming the limitations inherented in considering only uniform road segments. The methodology consists of: dividing a sample of roads into segments; grouping them into quite homogeneous road environments using cluster analysis; and identifying the influence of skid resistance and texture depth on road accidents in each environment by using generalized linear models. The application of this methodology is demonstrated for eight roads. Based on real data from accidents and road characteristics, three compound road environments were established where the pavement surface properties significantly influence the occurrence of accidents. Results have showed clearly that road environments where braking maneuvers are more common or those with small radii of curvature and high speeds require higher skid resistance and texture depth as an important contribution to the accident prevention. Copyright © 2013 Elsevier Ltd. All rights reserved.
Lane Level Localization; Using Images and HD Maps to Mitigate the Lateral Error
NASA Astrophysics Data System (ADS)
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.
ERIC Educational Resources Information Center
Brown, James Seay, Jr.; Sullivan-Gonzalez, Douglass
2002-01-01
Outlines an innovative way of teaching "World History Since 1500" at Samford University (Birmingham, Alabama) called the "great roads" approach, centered upon important roads in a country's history. Presents the "Veracruz to Mexico City corridor" case study used to teach a Latin American modern history course. (CMK)
New Approach to Road Construction in Oil-Producing Regions of Western Siberia
NASA Astrophysics Data System (ADS)
Piirainen, V. Y.; Estrin, Y.
2017-10-01
This article presents, as a polemic exercise, a new approach to road construction in marshland areas of oil and gas producing regions of Western Siberia. The approach is based on the use of novel modular elements that can be assembled into an integral structure by means of topological interlocking. The use of modern superlight concrete in conjunction with the new design systems based on the modular principle opens up new avenues to solving problems of road construction in regions with unstable, boggy soils.
Evaluation of Innovative Approaches to Curve Delineation for Two-Lane Rural Roads
DOT National Transportation Integrated Search
2018-06-01
Run-off-road crashes are a major problem for rural roads. These roads tend to be unlit, and drivers may have difficulty seeing or correctly predicting the curvature of horizontal curves. This leads to vehicles entering horizontal curves at speeds tha...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chinthavali, Supriya
Surface transportation road networks share structural properties similar to other complex networks (e.g., social networks, information networks, biological networks, and so on). This research investigates the structural properties of road networks for any possible correlation with the traffic characteristics such as link flows those determined independently. Additionally, we define a criticality index for the links of the road network that identifies the relative importance in the network. We tested our hypotheses with two sample road networks. Results show that, correlation exists between the link flows and centrality measures of a link of the road (dual graph approach is followed) andmore » the criticality index is found to be effective for one test network to identify the vulnerable nodes.« less
Finely Resolved On-Road PM2.5 and Estimated Premature Mortality in Central North Carolina.
Chang, Shih Ying; Vizuete, William; Serre, Marc; Vennam, Lakshmi Pradeepa; Omary, Mohammad; Isakov, Vlad; Breen, Michael; Arunachalam, Saravanan
2017-12-01
To quantify the on-road PM 2.5 -related premature mortality at a national scale, previous approaches to estimate concentrations at a 12-km × 12-km or larger grid cell resolution may not fully characterize concentration hotspots that occur near roadways and thus the areas of highest risk. Spatially resolved concentration estimates from on-road emissions to capture these hotspots may improve characterization of the associated risk, but are rarely used for estimating premature mortality. In this study, we compared the on-road PM 2.5 -related premature mortality in central North Carolina with two different concentration estimation approaches-(i) using the Community Multiscale Air Quality (CMAQ) model to model concentration at a coarser resolution of a 36-km × 36-km grid resolution, and (ii) using a hybrid of a Gaussian dispersion model, CMAQ, and a space-time interpolation technique to provide annual average PM 2.5 concentrations at a Census-block level (∼105,000 Census blocks). The hybrid modeling approach estimated 24% more on-road PM 2.5 -related premature mortality than CMAQ. The major difference is from the primary on-road PM 2.5 where the hybrid approach estimated 2.5 times more primary on-road PM 2.5 -related premature mortality than CMAQ due to predicted exposure hotspots near roadways that coincide with high population areas. The results show that 72% of primary on-road PM 2.5 premature mortality occurs within 1,000 m from roadways where 50% of the total population resides, highlighting the importance to characterize near-road primary PM 2.5 and suggesting that previous studies may have underestimated premature mortality due to PM 2.5 from traffic-related emissions. © 2017 Society for Risk Analysis.
Rhodes, Jonathan R.; Lunney, Daniel; Callaghan, John; McAlpine, Clive A.
2014-01-01
Roads and vehicular traffic are among the most pervasive of threats to biodiversity because they fragmenting habitat, increasing mortality and opening up new areas for the exploitation of natural resources. However, the number of vehicles on roads is increasing rapidly and this is likely to continue into the future, putting increased pressure on wildlife populations. Consequently, a major challenge is the planning of road networks to accommodate increased numbers of vehicles, while minimising impacts on wildlife. Nonetheless, we currently have few principles for guiding decisions on road network planning to reduce impacts on wildlife in real landscapes. We addressed this issue by developing an approach for quantifying the impact on wildlife mortality of two alternative mechanisms for accommodating growth in vehicle numbers: (1) increasing the number of roads, and (2) increasing traffic volumes on existing roads. We applied this approach to a koala (Phascolarctos cinereus) population in eastern Australia and quantified the relative impact of each strategy on mortality. We show that, in most cases, accommodating growth in traffic through increases in volumes on existing roads has a lower impact than building new roads. An exception is where the existing road network has very low road density, but very high traffic volumes on each road. These findings have important implications for how we design road networks to reduce their impacts on biodiversity. PMID:24646891
Rhodes, Jonathan R; Lunney, Daniel; Callaghan, John; McAlpine, Clive A
2014-01-01
Roads and vehicular traffic are among the most pervasive of threats to biodiversity because they fragmenting habitat, increasing mortality and opening up new areas for the exploitation of natural resources. However, the number of vehicles on roads is increasing rapidly and this is likely to continue into the future, putting increased pressure on wildlife populations. Consequently, a major challenge is the planning of road networks to accommodate increased numbers of vehicles, while minimising impacts on wildlife. Nonetheless, we currently have few principles for guiding decisions on road network planning to reduce impacts on wildlife in real landscapes. We addressed this issue by developing an approach for quantifying the impact on wildlife mortality of two alternative mechanisms for accommodating growth in vehicle numbers: (1) increasing the number of roads, and (2) increasing traffic volumes on existing roads. We applied this approach to a koala (Phascolarctos cinereus) population in eastern Australia and quantified the relative impact of each strategy on mortality. We show that, in most cases, accommodating growth in traffic through increases in volumes on existing roads has a lower impact than building new roads. An exception is where the existing road network has very low road density, but very high traffic volumes on each road. These findings have important implications for how we design road networks to reduce their impacts on biodiversity.
1. Launch facility, delta 6, approach road and gate, pole ...
1. Launch facility, delta 6, approach road and gate, pole marking the hardened intersite cable system in right center, commercial power pole outside fence in left center, view towards south - Ellsworth Air Force Base, Delta Flight, Launch Facility D-6, 4 miles north of Badlands National Park Headquarters, 4.5 miles east of Jackson County line on county road, Interior, Jackson County, SD
Kristopher R. Brown; W. Michael Aust; Kevin J. McGuire
2015-01-01
Reopening of abandoned legacy roads is common in forest operations and represents a reduced cost in comparison to new road construction. However, legacy roads may have lower road standards and require additional best management practice (BMP) implementation upon reopening to protect water quality. Silt fences and elevation measurements of trapped sediment were used to...
A quantitative approach to measure road network information based on edge diversity
NASA Astrophysics Data System (ADS)
Wu, Xun; Zhang, Hong; Lan, Tian; Cao, Weiwei; He, Jing
2015-12-01
The measure of map information has been one of the key issues in assessing cartographic quality and map generalization algorithms. It is also important for developing efficient approaches to transfer geospatial information. Road network is the most common linear object in real world. Approximately describe road network information will benefit road map generalization, navigation map production and urban planning. Most of current approaches focused on node diversities and supposed that all the edges are the same, which is inconsistent to real-life condition, and thus show limitations in measuring network information. As real-life traffic flow are directed and of different quantities, the original undirected vector road map was first converted to a directed topographic connectivity map. Then in consideration of preferential attachment in complex network study and rich-club phenomenon in social network, the from and to weights of each edge are assigned. The from weight of a given edge is defined as the connectivity of its end node to the sum of the connectivities of all the neighbors of the from nodes of the edge. After getting the from and to weights of each edge, edge information, node information and the whole network structure information entropies could be obtained based on information theory. The approach has been applied to several 1 square mile road network samples. Results show that information entropies based on edge diversities could successfully describe the structural differences of road networks. This approach is a complementarity to current map information measurements, and can be extended to measure other kinds of geographical objects.
Road profiling of traffic accidents in Jos, Nigeria, 1995-1999.
Bombom, Leonard S; Edino, Marcus O
2009-09-01
Road traffic accident data in Nigeria generally lack exact coordinate information. Accident analysis is, therefore, restricted to aggregate data on trends, magnitude and temporal dimensions. This article addresses the road accident problem in Jos between 1995 and 1999 through a road profiling approach. Results show that four gateway routes, seven multi-lane roadways (including two gateway routes) and seven road intersections accounted for 84% of all traffic accidents, 84% of injured casualties and 88% of fatalities. This approach allows for quantification of impacts of controlling for accidents by deliberate profiling of roads for close monitoring and policing. For example, reducing accident counts and fatalities by 50% each on gateway routes will amount to approximately 35 and 40% reduction in accident and fatality counts, respectively. Countermeasures must consider these roadways and intersections as important inputs in their accidents and casualty reduction targets.
View of deck of pony truss approach span. Deck system ...
View of deck of pony truss approach span. Deck system has failed at northwest corner. Looking south. - Naval Supply Annex Stockton, Daggett Road Bridge, Daggett Road traversing Burns Cut Off, Stockton, San Joaquin County, CA
Stuckey, R; Pratt, SG; Murray, W
2015-01-01
Work-related travel and transport by road is fundamental for industry, government and organisations. Traditionally, road safety interventions at societal level have focussed on improving road and vehicle engineering and changing road-user behaviour through transport laws and safety campaigns. Crash data indicate that significant numbers of road-user fatalities occur while driving to or for work. Therefore, workplace initiatives can improve both road and worker safety. This paper reviews regulatory approaches to work-related road safety (WRRS) in Australia, the United Kingdom and United States, identifying significant and consistent gaps in policy, management and research. In all three countries, responsibility for managing and regulating WRRS is spread across government agencies, without a single coordinating body. This paper makes the case that integrating management of WRRS into regulatory and non-regulatory occupational health and safety (OHS) initiatives would foster and support collaboration between research and practice communities, ensuring a comprehensive evidence base for future programs. PMID:26279686
NASA Astrophysics Data System (ADS)
Lu, Feng; Liu, Kang; Duan, Yingying; Cheng, Shifen; Du, Fei
2018-07-01
A better characterization of the traffic influence among urban roads is crucial for traffic control and traffic forecasting. The existence of spatial heterogeneity imposes great influence on modeling the extent and degree of road traffic correlation, which is usually neglected by the traditional distance based method. In this paper, we propose a traffic-enhanced community detection approach to spatially reveal the traffic correlation in city road networks. First, the road network is modeled as a traffic-enhanced dual graph with the closeness between two road segments determined not only by their topological connection, but also by the traffic correlation between them. Then a flow-based community detection algorithm called Infomap is utilized to identify the road segment clusters. Evaluated by Moran's I, Calinski-Harabaz Index and the traffic interpolation application, we find that compared to the distance based method and the community based method, our proposed traffic-enhanced community based method behaves better in capturing the extent of traffic relevance as both the topological structure of the road network and the traffic correlations among urban roads are considered. It can be used in more traffic-related applications, such as traffic forecasting, traffic control and guidance.
1. Context view shows approach of access road to summit, ...
1. Context view shows approach of access road to summit, communication towers and NW corner of lookout tower at center right. Camera is pointed SE. - Chelan Butte Lookout, Summit of Chelan Butte, Chelan, Chelan County, WA
A Public Health Perspective of Road Traffic Accidents
Gopalakrishnan, S.
2012-01-01
Road traffic accidents (RTAs) have emerged as an important public health issue which needs to be tackled by a multi-disciplinary approach. The trend in RTA injuries and death is becoming alarming in countries like India. The number of fatal and disabling road accident happening is increasing day by day and is a real public health challenge for all the concerned agencies to prevent it. The approach to implement the rules and regulations available to prevent road accidents is often ineffective and half-hearted. Awareness creation, strict implementation of traffic rules, and scientific engineering measures are the need of the hour to prevent this public health catastrophe. This article is intended to create awareness among the health professionals about the various modalities available to prevent road accidents and also to inculcate a sense of responsibility toward spreading the message of road safety as a good citizen of our country. PMID:24479025
Muir, Carlyn; Johnston, Ian R; Howard, Eric
2018-06-01
The Victorian Safe System approach to road safety slowly evolved from a combination of the Swedish Vision Zero philosophy and the Sustainable Safety model developed by the Dutch. The Safe System approach reframes the way in which road safety is viewed and managed. This paper presents a case study of the institutional change required to underpin the transformation to a holistic approach to planning and managing road safety in Victoria, Australia. The adoption and implementation of a Safe System approach require strong institutional leadership and close cooperation among all the key agencies involved, and Victoria was fortunate in that it had a long history of strong interagency mechanisms in place. However, the challenges in the implementation of the Safe System strategy in Victoria are generally neither technical nor scientific; they are predominantly social and political. While many governments purport to develop strategies based on Safe System thinking, on-the-ground action still very much depends on what politicians perceive to be publicly acceptable, and Victoria is no exception. This is a case study of the complexity of institutional change and is presented in the hope that the lessons may prove useful for others seeking to adopt more holistic planning and management of road safety. There is still much work to be done in Victoria, but the institutional cultural shift has taken root. Ongoing efforts must be continued to achieve alert and compliant road users; however, major underpinning benefits will be achieved through focusing on road network safety improvements (achieving forgiving infrastructure, such as wire rope barriers) in conjunction with reviews of posted speed limits (to be set in response to the level of protection offered by the road infrastructure) and by the progressive introduction into the fleet of modern vehicle safety features. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
The road plan model: Information model for planning road building activities
NASA Technical Reports Server (NTRS)
Azinhal, Rafaela K.; Moura-Pires, Fernando
1994-01-01
The general building contractor is presented with an information model as an approach for deriving a high-level work plan of construction activities applied to road building. Road construction activities are represented in a Road Plan Model (RPM), which is modeled in the ISO standard STEP/EXPRESS and adopts various concepts from the GARM notation. The integration with the preceding road design stage and the succeeding phase of resource scheduling is discussed within the framework of a Road Construction Model. Construction knowledge is applied to the road design and the terrain model of the surrounding road infrastructure for the instantiation of the RPM. Issues regarding the implementation of a road planner application supporting the RPM are discussed.
Iqbal, Asif; Allan, Andrew; Zito, Rocco
2016-03-01
The study aims to develop an emission inventory (EI) approach and conduct an inventory for vehicular sources in Dhaka City, Bangladesh. A meso-scale modelling approach was adopted for the inventory; the factors that influence the emissions and the magnitude of emission variation were identified and reported on, which was an innovative approach to account emissions unlike the conventional inventory approaches. Two techniques for the emission inventory were applied, viz. (i) a combined top-down and bottom-up approach that considered the total vehicle population and the average diurnal on-road vehicle speed profile in the city and (ii) a bottom-up approach that accounted for road link-specific emissions of the city considering diurnal traffic volume and speed profiles of the respective roads. For the bottom-up approach, road link-specific detailed data were obtained through field survey in 2012, where mid-block traffic count of the day, vehicle speed profile, road network and congestion data were collected principally. The emission variances for the change in transport system characteristics (like change in fuel type, AC usage pattern, increased speed and reduced congestion/stopping) were predicted and analysed in this study; congestion influenced average speed of the vehicles, and fuel types in the vehicles were identified as the major stressors. The study performance was considered reasonable when comparing with the limited number of similar studies conducted earlier. Given the increasing trend of private vehicles each year coupled with increasing traffic congestion, the city is under threat of increased vehicular emissions unless a good management strategy is implemented. Although the inventory is conducted for Dhaka and the result may be important locally, the approach adopted in this research is innovative in nature to be followed for conducting research on other urban transport systems.
Benchmarking road safety performance: Identifying a meaningful reference (best-in-class).
Chen, Faan; Wu, Jiaorong; Chen, Xiaohong; Wang, Jianjun; Wang, Di
2016-01-01
For road safety improvement, comparing and benchmarking performance are widely advocated as the emerging and preferred approaches. However, there is currently no universally agreed upon approach for the process of road safety benchmarking, and performing the practice successfully is by no means easy. This is especially true for the two core activities of which: (1) developing a set of road safety performance indicators (SPIs) and combining them into a composite index; and (2) identifying a meaningful reference (best-in-class), one which has already obtained outstanding road safety practices. To this end, a scientific technique that can combine the multi-dimensional safety performance indicators (SPIs) into an overall index, and subsequently can identify the 'best-in-class' is urgently required. In this paper, the Entropy-embedded RSR (Rank-sum ratio), an innovative, scientific and systematic methodology is investigated with the aim of conducting the above two core tasks in an integrative and concise procedure, more specifically in a 'one-stop' way. Using a combination of results from other methods (e.g. the SUNflower approach) and other measures (e.g. Human Development Index) as a relevant reference, a given set of European countries are robustly ranked and grouped into several classes based on the composite Road Safety Index. Within each class the 'best-in-class' is then identified. By benchmarking road safety performance, the results serve to promote best practice, encourage the adoption of successful road safety strategies and measures and, more importantly, inspire the kind of political leadership needed to create a road transport system that maximizes safety. Copyright © 2015 Elsevier Ltd. All rights reserved.
Costs of performance based maintenance for local roads: Case study Albania
NASA Astrophysics Data System (ADS)
Jokanović, Igor; Grujić, Bojana; Zeljić, Dragana; Grujić, Žarko; Svilar, Mila
2017-12-01
The provision and maintenance of road infrastructure is a major global business, consequently it is essential that road maintenance services are provided in the most cost effective manner. Without regular maintenance, roads can rapidly fall into disrepair, preventing realization of the longer term impacts of road improvements on development, such as increased agricultural production and growth in school enrollment, which is of particular importance for a network of local (access) roads. Inadequate local roads maintenance in Albania is proposed to be solved by implementing performance based maintenance approach for which the costing exercise is presented within the paper.
Prediction of surface distress using neural networks
NASA Astrophysics Data System (ADS)
Hamdi, Hadiwardoyo, Sigit P.; Correia, A. Gomes; Pereira, Paulo; Cortez, Paulo
2017-06-01
Road infrastructures contribute to a healthy economy throughout a sustainable distribution of goods and services. A road network requires appropriately programmed maintenance treatments in order to keep roads assets in good condition, providing maximum safety for road users under a cost-effective approach. Surface Distress is the key element to identify road condition and may be generated by many different factors. In this paper, a new approach is aimed to predict Surface Distress Index (SDI) values following a data-driven approach. Later this model will be accordingly applied by using data obtained from the Integrated Road Management System (IRMS) database. Artificial Neural Networks (ANNs) are used to predict SDI index using input variables related to the surface of distress, i.e., crack area and width, pothole, rutting, patching and depression. The achieved results show that ANN is able to predict SDI with high correlation factor (R2 = 0.996%). Moreover, a sensitivity analysis was applied to the ANN model, revealing the influence of the most relevant input parameters for SDI prediction, namely rutting (59.8%), crack width (29.9%) and crack area (5.0%), patching (3.0%), pothole (1.7%) and depression (0.3%).
Do not blame the driver: a systems analysis of the causes of road freight crashes.
Newnam, Sharon; Goode, Natassia
2015-03-01
Although many have advocated a systems approach in road transportation, this view has not meaningfully penetrated road safety research, practice or policy. In this study, a systems theory-based approach, Rasmussens's (1997) risk management framework and associated Accimap technique, is applied to the analysis of road freight transportation crashes. Twenty-seven highway crash investigation reports were downloaded from the National Transport Safety Bureau website. Thematic analysis was used to identify the complex system of contributory factors, and relationships, identified within the reports. The Accimap technique was then used to represent the linkages and dependencies within and across system levels in the road freight transportation industry and to identify common factors and interactions across multiple crashes. The results demonstrate how a systems approach can increase knowledge in this safety critical domain, while the findings can be used to guide prevention efforts and the development of system-based investigation processes for the heavy vehicle industry. A research agenda for developing an investigation technique to better support the application of the Accimap technique by practitioners in road freight transportation industry is proposed. Copyright © 2015 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Matulla, Christoph; Namyslo, Joachim; Fuchs, Tobias; Türk, Konrad
2013-04-01
The European road sector is vulnerable to extreme weather phenomena, which can cause large socio-economic losses. Almost every year there occur several weather triggered events (like heavy precipitation, floods, landslides, high winds, snow and ice, heat or cold waves, etc.), that disrupt transportation, knock out power lines, cut off populated regions from the outside and so on. So, in order to avoid imbalances in the supply of vital goods to people as well as to prevent negative impacts on health and life of people travelling by car it is essential to know present and future threats to roads. Climate change might increase future threats to roads. CliPDaR focuses on parts of the European road network and contributes, based on the current body of knowledge, to the establishment of guidelines helping to decide which methods and scenarios to apply for the estimation of future climate change based challenges in the field of road maintenance. Based on regional scale climate change projections specific road-impact models are applied in order to support protection measures. In recent years, it has been recognised that it is essential to assess the uncertainty and reliability of given climate projections by using ensemble approaches and downscaling methods. A huge amount of scientific work has been done to evaluate these approaches with regard to reliability and usefulness for investigations on possible impacts of climate changes. CliPDaR is going to collect the existing approaches and methodologies in European countries, discuss their differences and - in close cooperation with the road owners - develops a common line on future applications of climate projection data to road impact models. As such, the project will focus on reviewing and assessing existing regional climate change projections regarding transnational highway transport needs. The final project report will include recommendations how the findings of CliPDaR may support the decision processes of European national road administrations regarding possible future climate change impacts. First project results are presented at the conference.
A Method for Extracting Road Boundary Information from Crowdsourcing Vehicle GPS Trajectories.
Yang, Wei; Ai, Tinghua; Lu, Wei
2018-04-19
Crowdsourcing trajectory data is an important approach for accessing and updating road information. In this paper, we present a novel approach for extracting road boundary information from crowdsourcing vehicle traces based on Delaunay triangulation (DT). First, an optimization and interpolation method is proposed to filter abnormal trace segments from raw global positioning system (GPS) traces and interpolate the optimization segments adaptively to ensure there are enough tracking points. Second, constructing the DT and the Voronoi diagram within interpolated tracking lines to calculate road boundary descriptors using the area of Voronoi cell and the length of triangle edge. Then, the road boundary detection model is established integrating the boundary descriptors and trajectory movement features (e.g., direction) by DT. Third, using the boundary detection model to detect road boundary from the DT constructed by trajectory lines, and a regional growing method based on seed polygons is proposed to extract the road boundary. Experiments were conducted using the GPS traces of taxis in Beijing, China, and the results show that the proposed method is suitable for extracting the road boundary from low-frequency GPS traces, multi-type road structures, and different time intervals. Compared with two existing methods, the automatically extracted boundary information was proved to be of higher quality.
A Method for Extracting Road Boundary Information from Crowdsourcing Vehicle GPS Trajectories
Yang, Wei
2018-01-01
Crowdsourcing trajectory data is an important approach for accessing and updating road information. In this paper, we present a novel approach for extracting road boundary information from crowdsourcing vehicle traces based on Delaunay triangulation (DT). First, an optimization and interpolation method is proposed to filter abnormal trace segments from raw global positioning system (GPS) traces and interpolate the optimization segments adaptively to ensure there are enough tracking points. Second, constructing the DT and the Voronoi diagram within interpolated tracking lines to calculate road boundary descriptors using the area of Voronoi cell and the length of triangle edge. Then, the road boundary detection model is established integrating the boundary descriptors and trajectory movement features (e.g., direction) by DT. Third, using the boundary detection model to detect road boundary from the DT constructed by trajectory lines, and a regional growing method based on seed polygons is proposed to extract the road boundary. Experiments were conducted using the GPS traces of taxis in Beijing, China, and the results show that the proposed method is suitable for extracting the road boundary from low-frequency GPS traces, multi-type road structures, and different time intervals. Compared with two existing methods, the automatically extracted boundary information was proved to be of higher quality. PMID:29671792
Real-time road detection in infrared imagery
NASA Astrophysics Data System (ADS)
Andre, Haritini E.; McCoy, Keith
1990-09-01
Automatic road detection is an important part in many scene recognition applications. The extraction of roads provides a means of navigation and position update for remotely piloted vehicles or autonomous vehicles. Roads supply strong contextual information which can be used to improve the performance of automatic target recognition (ATh) systems by directing the search for targets and adjusting target classification confidences. This paper will describe algorithmic techniques for labeling roads in high-resolution infrared imagery. In addition, realtime implementation of this structural approach using a processor array based on the Martin Marietta Geometric Arithmetic Parallel Processor (GAPPTh) chip will be addressed. The algorithm described is based on the hypothesis that a road consists of pairs of line segments separated by a distance "d" with opposite gradient directions (antiparallel). The general nature of the algorithm, in addition to its parallel implementation in a single instruction, multiple data (SIMD) machine, are improvements to existing work. The algorithm seeks to identify line segments meeting the road hypothesis in a manner that performs well, even when the side of the road is fragmented due to occlusion or intersections. The use of geometrical relationships between line segments is a powerful yet flexible method of road classification which is independent of orientation. In addition, this approach can be used to nominate other types of objects with minor parametric changes.
Montero, Kerry; Spencer, Graham; Ariens, Bernadette
2012-06-01
This paper reports on a programme to improve road safety awareness in an industrial community in the vicinity of Jakarta, in Indonesia. Adapting the model of a successful community and school-based programme in Victoria, in Australia, and using a peer education approach, 16 employees of a major manufacturing company were trained to implement road safety education programmes amongst their peers. Specific target groups for the educators were colleagues, schools and the local community. Over 2 days the employees, from areas as diverse as production, public relations, personnel services, administration and management, learned about road safety facts, causes of traffic casualties, prevention approaches and peer education strategies. They explored and developed strategies to use with their respective target groups and practised health education skills. The newly trained workers received certificates to acknowledge them as 'SmartRoads Ambassadors' and, with follow-up support and development, became road safety educators with a commitment and responsibility to deliver education to their respective work and local communities. This paper argues that the model has potential to provide an effective and locally relevant response to road safety issues in similar communities.
Hotspots identification and ranking for road safety improvement: an alternative approach.
Coll, Bronagh; Moutari, Salissou; Marshall, Adele H
2013-10-01
During the last decade, the concept of composite performance index, brought from economic and business statistics, has become a popular practice in the field of road safety, namely for the identification and classification of worst performing areas or time slots also known as hotspots. The overall quality of a composite index depends upon the complexity of phenomena of interest as well as the relevance of the methodological approach used to aggregate the various indicators into a single composite index. However, current aggregation methods used to estimate the composite road safety performance index suffer from various deficiencies at both the theoretical and operational level; these include the correlation and compensability between indicators, the weighting of the indicators as well as their high "degree of freedom" which enables one to readily manipulate them to produce desired outcomes (Munda and Nardo, 2003, 2005, 2009). The objective of this study is to contribute to the ongoing research effort on the estimation of road safety composite index for hotspots' identification and ranking. The aggregation method for constructing the composite road safety performance index introduced in this paper, strives to minimize the aforementioned deficiencies of the current approaches. Furthermore, this new method can be viewed as an intelligent decision support system for road safety performance evaluation, in order to prioritize interventions for road safety improvement. Copyright © 2013 Elsevier Ltd. All rights reserved.
View of approach span and movable span, looking southeast from ...
View of approach span and movable span, looking southeast from navy land. Note that navigational channel exists only on north side of movable span. - Naval Supply Annex Stockton, Daggett Road Bridge, Daggett Road traversing Burns Cut Off, Stockton, San Joaquin County, CA
DOT National Transportation Integrated Search
1997-05-01
Current pavement design procedures are based principally on empirical approaches. The current trend toward developing more mechanistic-empirical type pavement design methods led Minnesota to develop the Minnesota Road Research Project (Mn/ROAD), a lo...
Multilane Traffic Flow Modeling Using Cellular Automata Theory
NASA Astrophysics Data System (ADS)
Chechina, Antonina; Churbanova, Natalia; Trapeznikova, Marina
2018-02-01
The paper deals with the mathematical modeling of traffic flows on urban road networks using microscopic approach. The model is based on the cellular automata theory and presents a generalization of the Nagel-Schreckenberg model to a multilane case. The created program package allows to simulate traffic on various types of road fragments (T or X type intersection, strait road elements, etc.) and on road networks that consist of these elements. Besides that, it allows to predict the consequences of various decisions regarding road infrastructure changes, such as: number of lanes increasing/decreasing, putting new traffic lights into operation, building new roads, entrances/exits, road junctions.
Modelling road accidents: An approach using structural time series
NASA Astrophysics Data System (ADS)
Junus, Noor Wahida Md; Ismail, Mohd Tahir
2014-09-01
In this paper, the trend of road accidents in Malaysia for the years 2001 until 2012 was modelled using a structural time series approach. The structural time series model was identified using a stepwise method, and the residuals for each model were tested. The best-fitted model was chosen based on the smallest Akaike Information Criterion (AIC) and prediction error variance. In order to check the quality of the model, a data validation procedure was performed by predicting the monthly number of road accidents for the year 2012. Results indicate that the best specification of the structural time series model to represent road accidents is the local level with a seasonal model.
Kristopher Brown; Kevin J. McGuire; W. Michael Aust; W. Cully Hession; C. Andrew Dolloff
2014-01-01
Direct sediment inputs from forest roads at stream crossings are a major concern for water quality and aquatic habitat. Legacy roadâstream crossing approaches, or the section of road leading to the stream, may have poor water and grade control upon reopening, thus increasing the potential for negative impacts to water quality. Rainfall simulation experiments were...
DOT National Transportation Integrated Search
2018-02-02
One approach that has been proposed to address the limitations of the current reactive safetymonitoring approaches is the use of road safety audits (RSAs). As part of an RSA, the existing or expected characteristics and traffic conditions of a locati...
Road Infrastructure Safety Management in Poland
NASA Astrophysics Data System (ADS)
Budzynski, Marcin; Jamroz, Kazimierz; Kustra, Wojciech; Michalski, Lech; Gaca, Stanislaw
2017-10-01
The objective of road safety infrastructure management is to ensure that when roads are planned, designed, built and used road risks can be identified, assessed and mitigated. Road transport safety is significantly less developed than that of rail, water and air transport. The average individual risk of being a fatality in relation to the distance covered is thirty times higher in road transport that in the other modes. This is mainly because the different modes have a different approach to safety management and to the use of risk management methods and tools. In recent years Poland has had one of the European Union’s highest road death numbers. In 2016 there were 3026 fatalities on Polish roads with 40,766 injuries. Protecting road users from the risk of injury and death should be given top priority. While Poland’s national and regional road safety programmes address this problem and are instrumental in systematically reducing the number of casualties, the effects are far from the expectations. Modern approaches to safety focus on three integrated elements: infrastructure measures, safety management and safety culture. Due to its complexity, the process of road safety management requires modern tools to help with identifying road user risks, assess and evaluate the safety of road infrastructure and select effective measures to improve road safety. One possible tool for tackling this problem is the risk-based method for road infrastructure safety management. European Union Directive 2008/96/EC regulates and proposes a list of tools for managing road infrastructure safety. Road safety tools look at two criteria: the life cycle of a road structure and the process of risk management. Risk can be minimized through the application of the proposed interventions during design process as reasonable. The proposed methods of risk management bring together two stages: risk assessment and risk response occurring within the analyzed road structure (road network, road stretch, road section, junction, etc.). The objective of the methods is to help road authorities to take rational decisions in the area of road safety and road infrastructure safety and understand the consequences occurring in the particular phases of road life cycle. To help with assessing the impact of a road project on the safety of related roads, a method was developed for long-term forecasts of accidents and accident cost estimation as well as a risk classification to identify risks that are not acceptable risks. With regard to road safety audits and road safety inspection, a set of principles was developed to identify risks and the basic classification of mistakes and omissions. This work has added to the Polish experience of preparing and implementing such tools within the competent road authorities.
Habitat or matrix: which is more relevant to predict road-kill of vertebrates?
Bueno, C; Sousa, C O M; Freitas, S R
2015-11-01
We believe that in tropics we need a community approach to evaluate road impacts on wildlife, and thus, suggest mitigation measures for groups of species instead a focal-species approach. Understanding which landscape characteristics indicate road-kill events may also provide models that can be applied in other regions. We intend to evaluate if habitat or matrix is more relevant to predict road-kill events for a group of species. Our hypothesis is: more permeable matrix is the most relevant factor to explain road-kill events. To test this hypothesis, we chose vertebrates as the studied assemblage and a highway crossing in an Atlantic Forest region in southeastern Brazil as the study site. Logistic regression models were designed using presence/absence of road-kill events as dependent variables and landscape characteristics as independent variables, which were selected by Akaike's Information Criterion. We considered a set of candidate models containing four types of simple regression models: Habitat effect model; Matrix types effect models; Highway effect model; and, Reference models (intercept and buffer distance). Almost three hundred road-kills and 70 species were recorded. River proximity and herbaceous vegetation cover, both matrix effect models, were associated to most road-killed vertebrate groups. Matrix was more relevant than habitat to predict road-kill of vertebrates. The association between river proximity and road-kill indicates that rivers may be a preferential route for most species. We discuss multi-species mitigation measures and implications to movement ecology and conservation strategies.
GIS Data Based Automatic High-Fidelity 3D Road Network Modeling
NASA Technical Reports Server (NTRS)
Wang, Jie; Shen, Yuzhong
2011-01-01
3D road models are widely used in many computer applications such as racing games and driving simulations_ However, almost all high-fidelity 3D road models were generated manually by professional artists at the expense of intensive labor. There are very few existing methods for automatically generating 3D high-fidelity road networks, especially those existing in the real world. This paper presents a novel approach thai can automatically produce 3D high-fidelity road network models from real 2D road GIS data that mainly contain road. centerline in formation. The proposed method first builds parametric representations of the road centerlines through segmentation and fitting . A basic set of civil engineering rules (e.g., cross slope, superelevation, grade) for road design are then selected in order to generate realistic road surfaces in compliance with these rules. While the proposed method applies to any types of roads, this paper mainly addresses automatic generation of complex traffic interchanges and intersections which are the most sophisticated elements in the road networks
Dynamic rockfall risk assessment along the SS113 coastal road (Northern Sicily)
NASA Astrophysics Data System (ADS)
Mastrolembo, V. Brunella; Penna, Ivanna; Voumard, Jérémie; Jaboyedoff, Michel
2016-04-01
Rockfalls are natural hazards that usually affect only small areas. However, due to the big amount of material that can be moved and the associated kinetic energy they can cost serious damages to infrastructures and people. Even fairly small rockfall fragments are a significant hazard if deposited on a highway or along a rail-road track since they are not easily detected and can cause accidents or derailments. Rockfalls can also cause the closure of streets resulting in long term indirect economic losses due to transportation delays as well as to the impact on the commercial and tourist activities. In letterature there are numerous examples of rockfall risk assessments along transportation corridors, most of them are based on the use of standard risk estimation methods. The latters are static approaches founded on a macroscopic view of road traffic, assumed as uniform in space and time, thus characterized by average values of parameters. Lately, a new dynamic approach has been developed within the 'risk analysis group' at the University of Lausanne (Voumard, 2013). It consists of a kinematic interpretation of road traffic where vehicles are parametrized as single entities with different characteristics, speed, dimensions and behaviour. We apply this new approach to estimate the dynamic risk due to rockfall occurrence on the SS113 national road running along the northern coast of Sicily. In this work we focus our attention on a ≈10 km section along which the SS113 road and a railway connect all the costal villages going through very steep cliffs and very close to the sea with evident problems of erosion and maintenance. The area is a tourist destination and many hotels and facilities are found along the road. Moreover the area was already hit in the past by numerous rockfalls resulting in the closure of the road for periods running from a few days up to a few years with big direct and indirect damages to the local socio-economic activities. In order to achieve a 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.
A preliminary study of mechanistic approach in pavement design to accommodate climate change effects
NASA Astrophysics Data System (ADS)
Harnaeni, S. R.; Pramesti, F. P.; Budiarto, A.; Setyawan, A.
2018-03-01
Road damage is caused by some factors, including climate changes, overload, and inappropriate procedure for material and development process. Meanwhile, climate change is a phenomenon which cannot be avoided. The effects observed include air temperature rise, sea level rise, rainfall changes, and the intensity of extreme weather phenomena. Previous studies had shown the impacts of climate changes on road damage. Therefore, several measures to anticipate the damage should be considered during the planning and construction in order to reduce the cost of road maintenance. There are three approaches generally applied in the design of flexible pavement thickness, namely mechanistic approach, mechanistic-empirical (ME) approach and empirical approach. The advantages of applying mechanistic approach or mechanistic-empirical (ME) approaches are its efficiency and reliability in the design of flexible pavement thickness as well as its capacity to accommodate climate changes in compared to empirical approach. However, generally, the design of flexible pavement thickness in Indonesia still applies empirical approach. This preliminary study aimed to emphasize the importance of the shifting towards a mechanistic approach in the design of flexible pavement thickness.
Road Network Extraction from Dsm by Mathematical Morphology and Reasoning
NASA Astrophysics Data System (ADS)
Li, Yan; Wu, Jianliang; Zhu, Lin; Tachibana, Kikuo
2016-06-01
The objective of this research is the automatic extraction of the road network in a scene of the urban area from a high resolution digital surface model (DSM). Automatic road extraction and modeling from remote sensed data has been studied for more than one decade. The methods vary greatly due to the differences of data types, regions, resolutions et al. An advanced automatic road network extraction scheme is proposed to address the issues of tedium steps on segmentation, recognition and grouping. It is on the basis of a geometric road model which describes a multiple-level structure. The 0-dimension element is intersection. The 1-dimension elements are central line and side. The 2-dimension element is plane, which is generated from the 1-dimension elements. The key feature of the presented approach is the cross validation for the three road elements which goes through the entire procedure of their extraction. The advantage of our model and method is that linear elements of the road can be derived directly, without any complex, non-robust connection hypothesis. An example of Japanese scene is presented to display the procedure and the performance of the approach.
View of pony truss approach span, showing metal caissons and ...
View of pony truss approach span, showing metal caissons and deck system, including metal floor beams and timber stringers. The same decking system was used on movable span. Looking north from civilian land. - Naval Supply Annex Stockton, Daggett Road Bridge, Daggett Road traversing Burns Cut Off, Stockton, San Joaquin County, CA
Understanding fatal older road user crash circumstances and risk factors.
Koppel, Sjaan; Bugeja, Lyndal; Smith, Daisy; Lamb, Ashne; Dwyer, Jeremy; Fitzharris, Michael; Newstead, Stuart; D'Elia, Angelo; Charlton, Judith
2018-02-28
This study used medicolegal data to investigate fatal older road user (ORU) crash circumstances and risk factors relating to four key components of the Safe System approach (e.g., roads and roadsides, vehicles, road users, and speeds) to identify areas of priority for targeted prevention activity. The Coroners Court of Victoria's Surveillance Database was searched to identify coronial records with at least one deceased ORU in the state of Victoria, Australia, for 2013-2014. Information relating to the ORU, crash characteristics and circumstances, and risk factors was extracted and analyzed. The average rate of fatal ORU crashes per 100,000 population was 8.1 (95% confidence interval [CI] 6.0-10.2), which was more than double the average rate of fatal middle-aged road user crashes (3.6, 95% CI 2.5-4.6). There was a significant relationship between age group and deceased road user type (χ 2 (15, N = 226) = 3.56, p < 0.001). The proportion of deceased drivers decreased with age, whereas the proportion of deceased pedestrians increased with age. The majority of fatal ORU crashes involved a counterpart (another vehicle: 59.4%; fixed/stationary object: 25.4%), and occurred "on road" (87.0%), on roads that were paved (94.2%), dry (74.2%), and had light traffic volume (38.3%). Road user error was identified by the police and/or coroner for the majority of fatal ORU crashes (57.9%), with a significant proportion of deceased ORU deemed to have "misjudged" (40.9%) or "failed to yield" (37.9%). Road user error was the most significant risk factor identified in fatal ORU crashes, which suggests that there is a limited capacity of the Victorian road system to fully accommodate road user errors. Initiatives related to safer roads and roadsides, vehicles, and speed zones, as well as behavioral approaches, are key areas of priority for targeted activity to prevent fatal older road user crashes in the future.
Multispectral Image Road Extraction Based Upon Automated Map Conflation
NASA Astrophysics Data System (ADS)
Chen, Bin
Road network extraction from remotely sensed imagery enables many important and diverse applications such as vehicle tracking, drone navigation, and intelligent transportation studies. There are, however, a number of challenges to road detection from an image. Road pavement material, width, direction, and topology vary across a scene. Complete or partial occlusions caused by nearby buildings, trees, and the shadows cast by them, make maintaining road connectivity difficult. The problems posed by occlusions are exacerbated with the increasing use of oblique imagery from aerial and satellite platforms. Further, common objects such as rooftops and parking lots are made of materials similar or identical to road pavements. This problem of common materials is a classic case of a single land cover material existing for different land use scenarios. This work addresses these problems in road extraction from geo-referenced imagery by leveraging the OpenStreetMap digital road map to guide image-based road extraction. The crowd-sourced cartography has the advantages of worldwide coverage that is constantly updated. The derived road vectors follow only roads and so can serve to guide image-based road extraction with minimal confusion from occlusions and changes in road material. On the other hand, the vector road map has no information on road widths and misalignments between the vector map and the geo-referenced image are small but nonsystematic. Properly correcting misalignment between two geospatial datasets, also known as map conflation, is an essential step. A generic framework requiring minimal human intervention is described for multispectral image road extraction and automatic road map conflation. The approach relies on the road feature generation of a binary mask and a corresponding curvilinear image. A method for generating the binary road mask from the image by applying a spectral measure is presented. The spectral measure, called anisotropy-tunable distance (ATD), differs from conventional measures and is created to account for both changes of spectral direction and spectral magnitude in a unified fashion. The ATD measure is particularly suitable for differentiating urban targets such as roads and building rooftops. The curvilinear image provides estimates of the width and orientation of potential road segments. Road vectors derived from OpenStreetMap are then conflated to image road features by applying junction matching and intermediate point matching, followed by refinement with mean-shift clustering and morphological processing to produce a road mask with piecewise width estimates. The proposed approach is tested on a set of challenging, large, and diverse image data sets and the performance accuracy is assessed. The method is effective for road detection and width estimation of roads, even in challenging scenarios when extensive occlusion occurs.
Sadiq, Abderrahmane; El Fazziki, Abdelaziz; Ouarzazi, Jamal; Sadgal, Mohamed
2016-01-01
This paper presents an integrated and adaptive problem-solving approach to control the on-road air quality by modeling the road infrastructure, managing traffic based on pollution level and generating recommendations for road users. The aim is to reduce vehicle emissions in the most polluted road segments and optimizing the pollution levels. For this we propose the use of historical and real time pollution records and contextual data to calculate the air quality index on road networks and generate recommendations for reassigning traffic flow in order to improve the on-road air quality. The resulting air quality indexes are used in the system's traffic network generation, which the cartography is represented by a weighted graph. The weights evolve according to the pollution indexes and path properties and the graph is therefore dynamic. Furthermore, the systems use the available pollution data and meteorological records in order to predict the on-road pollutant levels by using an artificial neural network based prediction model. The proposed approach combines the benefits of multi-agent systems, Big data technology, machine learning tools and the available data sources. For the shortest path searching in the road network, we use the Dijkstra algorithm over Hadoop MapReduce framework. The use Hadoop framework in the data retrieve and analysis process has significantly improved the performance of the proposed system. Also, the agent technology allowed proposing a suitable solution in terms of robustness and agility.
NASA Astrophysics Data System (ADS)
Ouerhani, Y.; Alfalou, A.; Desthieux, M.; Brosseau, C.
2017-02-01
We present a three-step approach based on the commercial VIAPIX® module for road traffic sign recognition and identification. Firstly, detection in a scene of all objects having characteristics of traffic signs is performed. This is followed by a first-level recognition based on correlation which consists in making a comparison between each detected object with a set of reference images of a database. Finally, a second level of identification allows us to confirm or correct the previous identification. In this study, we perform a correlation-based analysis by combining and adapting the Vander Lugt correlator with the nonlinear joint transformation correlator (JTC). Of particular significance, this approach permits to make a reliable decision on road traffic sign identification. We further discuss a robust scheme allowing us to track a detected road traffic sign in a video sequence for the purpose of increasing the decision performance of our system. This approach can have broad practical applications in the maintenance and rehabilitation of transportation infrastructure, or for drive assistance.
An Automated Road Roughness Detection from Mobile Laser Scanning Data
NASA Astrophysics Data System (ADS)
Kumar, P.; Angelats, E.
2017-05-01
Rough roads influence the safety of the road users as accident rate increases with increasing unevenness of the road surface. Road roughness regions are required to be efficiently detected and located in order to ensure their maintenance. Mobile Laser Scanning (MLS) systems provide a rapid and cost-effective alternative by providing accurate and dense point cloud data along route corridor. In this paper, an automated algorithm is presented for detecting road roughness from MLS data. The presented algorithm is based on interpolating smooth intensity raster surface from LiDAR point cloud data using point thinning process. The interpolated surface is further processed using morphological and multi-level Otsu thresholding operations to identify candidate road roughness regions. The candidate regions are finally filtered based on spatial density and standard deviation of elevation criteria to detect the roughness along the road surface. The test results of road roughness detection algorithm on two road sections are presented. The developed approach can be used to provide comprehensive information to road authorities in order to schedule maintenance and ensure maximum safety conditions for road users.
Irregular Warfare as a National Military Strategy Approach for Small States
2013-12-01
the most effective strategy for them. Analyses of large numbers of historical cases show that a conventional approach is a road to defeat for...this thesis is to illuminate the potential for small states to improve the effect of their military by adopting an irregular strategy. The thesis is... effective strategy for them. Analyses of large numbers of historical cases show that a conventional approach is a road to defeat for small states
Vision Sensor-Based Road Detection for Field Robot Navigation
Lu, Keyu; Li, Jian; An, Xiangjing; He, Hangen
2015-01-01
Road detection is an essential component of field robot navigation systems. Vision sensors play an important role in road detection for their great potential in environmental perception. In this paper, we propose a hierarchical vision sensor-based method for robust road detection in challenging road scenes. More specifically, for a given road image captured by an on-board vision sensor, we introduce a multiple population genetic algorithm (MPGA)-based approach for efficient road vanishing point detection. Superpixel-level seeds are then selected in an unsupervised way using a clustering strategy. Then, according to the GrowCut framework, the seeds proliferate and iteratively try to occupy their neighbors. After convergence, the initial road segment is obtained. Finally, in order to achieve a globally-consistent road segment, the initial road segment is refined using the conditional random field (CRF) framework, which integrates high-level information into road detection. We perform several experiments to evaluate the common performance, scale sensitivity and noise sensitivity of the proposed method. The experimental results demonstrate that the proposed method exhibits high robustness compared to the state of the art. PMID:26610514
Berlin, M A; Anand, Sheila
2014-01-01
This paper presents Direction based Hazard Routing Protocol (DHRP) for disseminating information about fixed road hazards such as road blocks, tree fall, boulders on road, snow pile up, landslide, road maintenance work and other obstacles to the vehicles approaching the hazardous location. The proposed work focuses on dissemination of hazard messages on highways with sparse traffic. The vehicle coming across the hazard would report the presence of the hazard. It is proposed to use Road Side fixed infrastructure Units for reliable and timely delivery of hazard messages to vehicles. The vehicles can then take appropriate safety action to avoid the hazardous location. The proposed protocol has been implemented and tested using SUMO simulator to generate road traffic and NS 2.33 network simulator to analyze the performance of DHRP. The performance of the proposed protocol was also compared with simple flooding protocol and the results are presented.
2. GENERAL VIEW SHOWING RELATION OF BRIDGE TO THE TOPOGRAPHY ...
2. GENERAL VIEW SHOWING RELATION OF BRIDGE TO THE TOPOGRAPHY OF THE APPROACH ROAD. - Speicher Bridge, Church Road over Tulpehocken Creek between Penn & North Heidelberg Townships, Bernville, Berks County, PA
Unsworth, Carolyn A; Baker, Anne
2014-10-01
Driver rehabilitation has the potential to improve on-road safety and is commonly recommended to clients. The aim of this systematic review was to identify what intervention approaches are used by occupational therapists as part of driver rehabilitation programmes, and to determine the effectiveness of these interventions. Six electronic databases (MEDLINE, CINAHL, PsycInfo, Embase, The Cochrane Library, and OTDBase) were searched. Two authors independently reviewed studies reporting all types of research designs and for all patient populations, provided the interventions could be administered by occupational therapists. The methodological quality of studies was assessed using the 'Downs and Black Instrument', and the level of evidence for each intervention approach was established using 'Centre for Evidence Based Medicine' criteria. Sixteen studies were included in the review. The most common type of intervention approach used was computer-based driving simulator training (n=8), followed by off-road skill-specific training (n=4), and off-road education programmes (n=3). Car adaptations/modifications were used in one of the included studies. There was significant variability between studies with regards to frequency, duration, and total number of intervention sessions, and the diagnoses of the participants. Of the four intervention approaches, there is evidence to support the effectiveness of off-road skill-specific training (with older clients), and computer-based driving simulator training (with both older clients and participants with acquired brain injury). Three types of intervention approaches are commonly reported, however, there is limited evidence to determine to effectiveness of these in improving fitness-to-drive. Further research is required, with clients from a range of diagnostic groups to establish evidence-based interventions and determine their effectiveness in improving these clients' on-road fitness-to-drive. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.
The combination of two training approaches to improve older adults' driving safety.
Bédard, Michel; Porter, Michelle M; Marshall, Shawn; Isherwood, Ivy; Riendeau, Julie; Weaver, Bruce; Tuokko, Holly; Molnar, Frank; Miller-Polgar, Jan
2008-03-01
An increasing number of older adults rely on the automobile for transportation. Educational approaches based on the specific needs of older drivers may help to optimize safe driving. We examined if the combination of an in-class education program with on-road education would lead to improvements in older drivers' knowledge of safe driving practices and on-road driving evaluations. We used a multisite, randomized controlled trial approach. Participants in the intervention group received the in-class and on-road education; those in the control group waited and were offered the education afterwards. We measured knowledge of safe driving practices before and after the in-class component of the program and on-road driving skills before and after the whole program. Participants' knowledge improved from 61% of correct answers before the in-class education component to 81% after (p < .001). The on-road evaluation results suggested improvements on some aspects of safe driving (e.g., moving in roadway, p < .05) but not on others. The results of this study demonstrate that education programs focused on the needs of older drivers may help improve their knowledge of safe driving practices and actual driving performance. Further research is required to determine if these changes will affect other variables such as driver confidence and crash rates.
Christie, Nicola; Sleney, Judith; Ahmed, Fatima; Knight, Elisabeth
2012-08-01
In the UK the most disadvantaged in society are more likely than those more affluent to be injured or killed in a road traffic collision and therefore it is a major cause of health inequality. There is a strong link between ethnicity, deprivation and injury. Whilst national road traffic injury data does not collect ethnic origin the London accident and analysis group does in terms of broad categories such as 'white', 'black' and 'Asian'. Analysis of this data revealed the over-representation of child pedestrian casualties from a 'black' ethnic origin. This information led road safety practitioners in one London borough to map child pedestrian casualties against census data which identified the Somali community as being particularly at risk of being involved in a road traffic collision. Working with the community they sought to discuss and address road safety issues and introduced practical evidence based approaches such as child pedestrian training. The process evaluation of the project used a qualitative approach and showed that engaging with community partners and working across organisational boundaries was a useful strategy to gain an understanding of the Somali community. A bottom approach provided the community with a sense of control and involvement which appears to add value in terms of reducing the sense of powerlessness that marginalised communities often feel. In terms of evaluation, small projects like these, lend themselves to a qualitative process evaluation though it has to be accepted that the strength of this evidence may be regarded as weak. Where possible routine injury data needs to take into account ethnicity which is a known risk factor for road casualty involvement which needs to be continually monitored.
Analysis of loss of time value during road maintenance project
NASA Astrophysics Data System (ADS)
Sudarsana, Dewa Ketut; Sanjaya, Putu Ari
2017-06-01
Lane closure is frequently performed in the execution of the road maintenance project. It has a negative impact on road users such as the loss of vehicle operating costs and the loss of time value. Nevertheless, analysis on loss of time value in Indonesia has not been carried out. The parameter of time value for the road users was the minimum wage city/region approach. Vehicle speed of pre-construction was obtained by observation, while the speed during the road maintenance project was predicted by the speed of the pre-construction by multiplying it with the speed adjustment factor. In the case of execution of the National road maintenance project in the two-lane two-way urban and interurban road types in the fiscal year of 2015 in Bali province, the loss of time value was at the average of IDR 12,789,000/day/link road. The relationship of traffic volume and loss of time value of the road users was obtained by a logarithm model.
A review of models relevant to road safety.
Hughes, B P; Newstead, S; Anund, A; Shu, C C; Falkmer, T
2015-01-01
It is estimated that more than 1.2 million people die worldwide as a result of road traffic crashes and some 50 million are injured per annum. At present some Western countries' road safety strategies and countermeasures claim to have developed into 'Safe Systems' models to address the effects of road related crashes. Well-constructed models encourage effective strategies to improve road safety. This review aimed to identify and summarise concise descriptions, or 'models' of safety. The review covers information from a wide variety of fields and contexts including transport, occupational safety, food industry, education, construction and health. The information from 2620 candidate references were selected and summarised in 121 examples of different types of model and contents. The language of safety models and systems was found to be inconsistent. Each model provided additional information regarding style, purpose, complexity and diversity. In total, seven types of models were identified. The categorisation of models was done on a high level with a variation of details in each group and without a complete, simple and rational description. The models identified in this review are likely to be adaptable to road safety and some of them have previously been used. None of systems theory, safety management systems, the risk management approach, or safety culture was commonly or thoroughly applied to road safety. It is concluded that these approaches have the potential to reduce road trauma. Copyright © 2014 Elsevier Ltd. All rights reserved.
NASA Technical Reports Server (NTRS)
Sowers, J.; Mehrotra, R.; Sethi, I. K.
1989-01-01
A method for extracting road boundaries using the monochrome image of a visual road scene is presented. The statistical information regarding the intensity levels present in the image along with some geometrical constraints concerning the road are the basics of this approach. Results and advantages of this technique compared to others are discussed. The major advantages of this technique, when compared to others, are its ability to process the image in only one pass, to limit the area searched in the image using only knowledge concerning the road geometry and previous boundary information, and dynamically adjust for inconsistencies in the located boundary information, all of which helps to increase the efficacy of this technique.
Road sign recognition using Viapix module and correlation
NASA Astrophysics Data System (ADS)
Ouerhani, Y.; Desthieux, M.; Alfalou, A.
2015-03-01
In this paper, we propose and validate a new system used to explore road assets. In this work we are interested on the vertical road signs. To do this, we are based on the combination of road signs detection, recognition and identification using data provides by sensors. The proposed approach consists on using panoramic views provided by the innovative device, VIAPIX®1, developed by our company ACTRIS2. We are based also on the optimized correlation technique for road signs recognition and identification on pictures. Obtained results shows the interest on using panoramic views compared to results obtained using images provided using only one camera.
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.
Hoang, Toan Minh; Hong, Hyung Gil; Vokhidov, Husan; Park, Kang Ryoung
2016-01-01
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. PMID:27548176
Experimental study designs to improve the evaluation of road mitigation measures for wildlife.
Rytwinski, Trina; van der Ree, Rodney; Cunnington, Glenn M; Fahrig, Lenore; Findlay, C Scott; Houlahan, Jeff; Jaeger, Jochen A G; Soanes, Kylie; van der Grift, Edgar A
2015-05-01
An experimental approach to road mitigation that maximizes inferential power is essential to ensure that mitigation is both ecologically-effective and cost-effective. Here, we set out the need for and standards of using an experimental approach to road mitigation, in order to improve knowledge of the influence of mitigation measures on wildlife populations. We point out two key areas that need to be considered when conducting mitigation experiments. First, researchers need to get involved at the earliest stage of the road or mitigation project to ensure the necessary planning and funds are available for conducting a high quality experiment. Second, experimentation will generate new knowledge about the parameters that influence mitigation effectiveness, which ultimately allows better prediction for future road mitigation projects. We identify seven key questions about mitigation structures (i.e., wildlife crossing structures and fencing) that remain largely or entirely unanswered at the population-level: (1) Does a given crossing structure work? What type and size of crossing structures should we use? (2) How many crossing structures should we build? (3) Is it more effective to install a small number of large-sized crossing structures or a large number of small-sized crossing structures? (4) How much barrier fencing is needed for a given length of road? (5) Do we need funnel fencing to lead animals to crossing structures, and how long does such fencing have to be? (6) How should we manage/manipulate the environment in the area around the crossing structures and fencing? (7) Where should we place crossing structures and barrier fencing? We provide experimental approaches to answering each of them using example Before-After-Control-Impact (BACI) study designs for two stages in the road/mitigation project where researchers may become involved: (1) at the beginning of a road/mitigation project, and (2) after the mitigation has been constructed; highlighting real case studies when available. Copyright © 2015 Elsevier Ltd. All rights reserved.
Evaluation of road approaches to four different types of stream crossings in the Virginia Piedmont
Matthew B. Carroll; W. Michael Aust; C. Andrew Dolloff; Robert M. Shaffer
2013-01-01
Erosion potential was estimated for road approaches during 4 phases of a timber harvesting scheduled for 23 stream crossings in the Virginia Piedmont. The objectives of this study were to: (1) examine four different types of stream crossing structures (steel bridges, pole bridges, standard culverts, and reenforced fords) in order to determine if the type of stream...
Behaviourally relevant road categorisation: a step towards self-explaining rural roads.
Weller, Gert; Schlag, Bernhard; Friedel, Tino; Rammin, Carmen
2008-07-01
In contrast to motorways, rural roads are characterised by a large variation in design, appearance and function which is reflected in a comparatively large number of rural road categories. Depending on these categories, a certain (normative) behaviour is usually expected from the driver. These normative behavioural expectations are conveyed to the driver either by formal cues (e.g. speed limit signs) or are expected to be inferred from the road appearance or the affordance (Gibson, J.J., 1986. The Ecological Approach to Visual Perception. Lawrence Erlbaum, Hillsdale (New Jersey)) of the respective road situation. Unsafe situations are likely to occur if the perceived message conveyed by cues or affordances does not match the normative behavioural expectations of the official road category. In order to avoid such mismatch it is important to know how drivers categorise (rural) roads and which elements are used for this subjective and behaviourally relevant road categorisation. We therefore summarized the processes behind this categorisation in a model and conducted a study in a laboratory setting during which subjects were asked to rate a variety of rural road pictures. The study revealed that drivers distinguish between three different rural road categories which can be distinguished with comparatively few objective criteria. Applying these criteria helps to categorise and design rural roads along self-explaining road principles.
Three-Dimensional Road Network by Fusion of Polarimetric and Interferometric SAR Data
NASA Technical Reports Server (NTRS)
Gamba, P.; Houshmand, B.
1998-01-01
In this paper a fuzzy classification procedure is applied to polarimetric radar measurements, and street pixels are detected. These data are successively grouped into consistent roads by means of a dynamic programming approach based on the fuzzy membership function values. Further fusion of the 2D road network extracted and 3D TOPSAR measurements provides a powerful way to analyze urban infrastructures.
Calibrated Multi-Temporal Edge Images for City Infrastructure Growth Assessment and Prediction
NASA Astrophysics Data System (ADS)
Al-Ruzouq, R.; Shanableh, A.; Boharoon, Z.; Khalil, M.
2018-03-01
Urban Growth or urbanization can be defined as the gradual process of city's population growth and infrastructure development. It is typically demonstrated by the expansion of a city's infrastructure, mainly development of its roads and buildings. Uncontrolled urban Growth in cities has been responsible for several problems that include living environment, drinking water, noise and air pollution, waste management, traffic congestion and hydraulic processes. Accurate identification of urban growth is of great importance for urban planning and water/land management. Recent advances in satellite imagery, in terms of improved spatial and temporal resolutions, allows for efficient identification of change patterns and the prediction of built-up areas. In this study, two approaches were adapted to quantify and assess the pattern of urbanization, in Ajman City at UAE, during the last three decades. The first approach relies on image processing techniques and multi-temporal Landsat satellite images with ground resolution varying between 15 to 60 meters. In this approach, the derived edge images (roads and buildings) were used as the basis of change detection. The second approach relies on digitizing features from high-resolution images captured at different years. The latest approach was adopted, as a reference and ground truth, to calibrate extracted edges from Landsat images. It has been found that urbanized area almost increased by 12 folds during the period 1975-2015 where the growth of buildings and roads were almost parallel until 2005 when the roads spatial expansion witnessed a steep increase due to the vertical expansion of the City. Extracted Edges features, were successfully used for change detection and quantification in term of buildings and roads.
Low-cost rural surface alternatives : literature review and recommendations.
DOT National Transportation Integrated Search
2013-12-01
Freezing and thawing action induces damage to unbound gravel roads in Iowa resulting in maintenance costs for secondary road departments. Some approaches currently used by County Engineers to deal with this problem include temporarily spreading rock ...
Photonics approach to traffic signs
NASA Astrophysics Data System (ADS)
Litwin, Dariusz; Galas, Jacek; CzyŻewski, Adam; Rymsza, Barbara; Kornalewski, Leszek; Kryszczyński, Tadeusz; Mikucki, Jerzy; Wikliński, Piotr; Daszkiewicz, Marek; Malasek, Jacek
2016-12-01
The automotive industry has been always a driving force for all economies. Despite of its beneficial meaning to every society it brings also many issues including wide area of road safety. The latter has been enforced by the increasing number of cars and the dynamic development of the traffic as a whole. Road signs and traffic lights are crucial in context of good traffic arrangement and its fluency. Traffic designers are used to treat horizontal road signs independently of vertical signs. However, modern light sources and growing flexibility in shaping optical systems create opportunity to design more advanced and smart solutions. In this paper we present an innovative, multidisciplinary approach that consists in tight interdependence of different traffic signals. We describe new optical systems together with their influence on the perception of the road user. The analysis includes maintenance and visibility in different weather conditions. A special attention has been focused on intersections of complex geometry.
Raffo, Veronica; Bliss, Tony; Shotten, Marc; Sleet, David; Blanchard, Claire
2013-12-01
This case study of the Argentina Road Safety Project demonstrates how the application of World Bank road safety project guidelines focused on institution building can accelerate knowledge transfer, scale up investment and improve the focus on results. The case study highlights road safety as a development priority and outlines World Bank initiatives addressing the implementation of the World Report on Road Traffic Injury's recommendations and the subsequent launch of the Decade of Action for Road Safety, from 2011-2020. The case study emphasizes the vital role played by the lead agency in ensuring sustainable road safety improvements and promoting the shift to a 'Safe System' approach, which necessitated the strengthening of all elements of the road safety management system. It summarizes road safety performance and institutional initiatives in Argentina leading up to the preparation and implementation of the project. We describe the project's development objectives, financing arrangements, specific components and investment staging. Finally, we discuss its innovative features and lessons learned, and present a set of supplementary guidelines, both to assist multilateral development banks and their clients with future road safety initiatives, and to encourage better linkages between the health and transportation sectors supporting them.
Explaining the road accident risk: weather effects.
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.
Objects Grouping for Segmentation of Roads Network in High Resolution Images of Urban Areas
NASA Astrophysics Data System (ADS)
Maboudi, M.; Amini, J.; Hahn, M.
2016-06-01
Updated road databases are required for many purposes such as urban planning, disaster management, car navigation, route planning, traffic management and emergency handling. In the last decade, the improvement in spatial resolution of VHR civilian satellite sensors - as the main source of large scale mapping applications - was so considerable that GSD has become finer than size of common urban objects of interest such as building, trees and road parts. This technological advancement pushed the development of "Object-based Image Analysis (OBIA)" as an alternative to pixel-based image analysis methods. Segmentation as one of the main stages of OBIA provides the image objects on which most of the following processes will be applied. Therefore, the success of an OBIA approach is strongly affected by the segmentation quality. In this paper, we propose a purpose-dependent refinement strategy in order to group road segments in urban areas using maximal similarity based region merging. For investigations with the proposed method, we use high resolution images of some urban sites. The promising results suggest that the proposed approach is applicable in grouping of road segments in urban areas.
Modeling and simulation of emergent behavior in transportation infrastructure restoration
Ojha, Akhilesh; Corns, Steven; Shoberg, Thomas G.; Qin, Ruwen; Long, Suzanna K.
2018-01-01
The objective of this chapter is to create a methodology to model the emergent behavior during a disruption in the transportation system and that calculates economic losses due to such a disruption, and to understand how an extreme event affects the road transportation network. The chapter discusses a system dynamics approach which is used to model the transportation road infrastructure system to evaluate the different factors that render road segments inoperable and calculate economic consequences of such inoperability. System dynamics models have been integrated with business process simulation model to evaluate, design, and optimize the business process. The chapter also explains how different factors affect the road capacity. After identifying the various factors affecting the available road capacity, a causal loop diagram (CLD) is created to visually represent the causes leading to a change in the available road capacity and the effects on travel costs when the available road capacity changes.
Judgment in crossing a road between objects coming in the opposite lane
NASA Astrophysics Data System (ADS)
Matsumiya, Kazumichi; Kaneko, Hirohiko
2008-05-01
When cars are oncoming in the opposite lane of a road, a driver is able to judge whether his/her car can cross the road at an intersection without a collision with the oncoming cars. We developed a model for the human judgment used to cross a road between oncoming objects. In the model, in order to make the judgment to cross the road, the human visual system compares the time interval it takes for an oncoming object to pass the observer with the time interval it takes for the observer to cross the road. We conducted a psychophysical experiment to test the model prediction. The result showed that human performance is in good agreement with the theoretical consequence provided by the model, suggesting that the human visual system uses not only the visually timed information of the approaching object but also the timed information of self-action for the judgment about crossing the road.
High-Fidelity Roadway Modeling and Simulation
NASA Technical Reports Server (NTRS)
Wang, Jie; Papelis, Yiannis; Shen, Yuzhong; Unal, Ozhan; Cetin, Mecit
2010-01-01
Roads are an essential feature in our daily lives. With the advances in computing technologies, 2D and 3D road models are employed in many applications, such as computer games and virtual environments. Traditional road models were generated by professional artists manually using modeling software tools such as Maya and 3ds Max. This approach requires both highly specialized and sophisticated skills and massive manual labor. Automatic road generation based on procedural modeling can create road models using specially designed computer algorithms or procedures, reducing the tedious manual editing needed for road modeling dramatically. But most existing procedural modeling methods for road generation put emphasis on the visual effects of the generated roads, not the geometrical and architectural fidelity. This limitation seriously restricts the applicability of the generated road models. To address this problem, this paper proposes a high-fidelity roadway generation method that takes into account road design principles practiced by civil engineering professionals, and as a result, the generated roads can support not only general applications such as games and simulations in which roads are used as 3D assets, but also demanding civil engineering applications, which requires accurate geometrical models of roads. The inputs to the proposed method include road specifications, civil engineering road design rules, terrain information, and surrounding environment. Then the proposed method generates in real time 3D roads that have both high visual and geometrical fidelities. This paper discusses in details the procedures that convert 2D roads specified in shape files into 3D roads and civil engineering road design principles. The proposed method can be used in many applications that have stringent requirements on high precision 3D models, such as driving simulations and road design prototyping. Preliminary results demonstrate the effectiveness of the proposed method.
Measuring Road Network Vulnerability with Sensitivity Analysis
Jun-qiang, Leng; Long-hai, Yang; Liu, Wei-yi; Zhao, Lin
2017-01-01
This paper focuses on the development of a method for road network vulnerability analysis, from the perspective of capacity degradation, which seeks to identify the critical infrastructures in the road network and the operational performance of the whole traffic system. This research involves defining the traffic utility index and modeling vulnerability of road segment, route, OD (Origin Destination) pair and road network. Meanwhile, sensitivity analysis method is utilized to calculate the change of traffic utility index due to capacity degradation. This method, compared to traditional traffic assignment, can improve calculation efficiency and make the application of vulnerability analysis to large actual road network possible. Finally, all the above models and calculation method is applied to actual road network evaluation to verify its efficiency and utility. This approach can be used as a decision-supporting tool for evaluating the performance of road network and identifying critical infrastructures in transportation planning and management, especially in the resource allocation for mitigation and recovery. PMID:28125706
2. EAST ELEVATION OF BRIDGE SEEN FROM THE NORTHEAST, SHOWING ...
2. EAST ELEVATION OF BRIDGE SEEN FROM THE NORTHEAST, SHOWING APPROACH OF CARRS MILL ROAD FROM EAST. - Mitchell's Mill Bridge, Spanning Winter's Run on Carrs Mill Road, west of Bel Air, Bel Air, Harford County, MD
Choosing rural road investments to help reduce poverty
DOT National Transportation Integrated Search
2000-10-01
The paper examines how rural road investment projects should be selected when the specific objective is taken to be poverty reduction. After critically reviewing past and current practices, an attempt is made to develop an operational approach that i...
Newnam, Sharon; Goode, Natassia; Salmon, Paul; Stevenson, Mark
2017-04-01
Road freight transport is considered to be one of the most dangerous industries in Australia, accounting for over 30% of all work fatalities. Whilst system reform (i.e., change to policy and practice) is needed, it is not clear what this reform should be, or what approaches should be used to drive it. This article argues that road freight transportation reform should be underpinned by a systems thinking approach. Efforts to understand crash causation should be focused beyond the driver and identify contributing factors at other levels with the road freight system. Accordingly, we present the findings from a study that examined whether Australian Coronial investigations into road freight crashes reflect support appropriate system reform. Content analysis was used to identify the contributing factors and interrelations implicated in the road freight crashes described in publicly available Australian Coroner's inquest reports from the last 10 years (2004-2014; n=21). The results found evidence to suggest that the Coronial inquests provide some understanding of the complex system of factors influencing road freight transportation crashes in Australia. However, there was a lack of evidence to suggest an understanding of system-based reform based on the identification of reductionist-focused recommendations. It is concluded that researchers and practitioners (ie., government and industry) need to work together to develop prevention efforts focused on system reforms. Systems thinking based data collection and analysis frameworks are urgently required to help develop this understanding in road freight transportation. Copyright © 2017 Elsevier Ltd. All rights reserved.
Linear stochastic evaluation of tyre vibration due to tyre/road excitation
NASA Astrophysics Data System (ADS)
Rustighi, E.; Elliott, S. J.; Finnveden, S.; Gulyás, K.; Mócsai, T.; Danti, M.
2008-03-01
Tyre/road interaction is recognised as the main source of interior and exterior noise for velocities over the 40 km/h. In this paper, a three-dimensional (3D) elemental approach has been adopted to predict the stochastic tyre vibration and hence the interior and exterior noise due to this kind of excitation. The road excitation has been modelled from the spectral density of a common road profile, supposing the road to be an isotropic surface. A linear Winkler bedding connects the 3D model of the tyre with the ground. The exterior noise has been evaluated by an elemental calculation of the radiation matrix of the tyre deformed by the static load on a concrete road. The noise inside the vehicle has also been calculated, using the transfer functions from the force transmitted to the hub and the noise inside the vehicle, which have been computed by a FEM model of a common car body. The simple formulation allows much quicker calculation than traditional nonlinear approaches, and appears to give results consistent with available measurements, although the effects of tyre rotation and of the nonlinearities in the contact model are yet to be quantified, and the method requires further experimental validation before practical application.
Harvesting geographic features from heterogeneous raster maps
NASA Astrophysics Data System (ADS)
Chiang, Yao-Yi
2010-11-01
Raster maps offer a great deal of geospatial information and are easily accessible compared to other geospatial data. However, harvesting geographic features locked in heterogeneous raster maps to obtain the geospatial information is challenging. This is because of the varying image quality of raster maps (e.g., scanned maps with poor image quality and computer-generated maps with good image quality), the overlapping geographic features in maps, and the typical lack of metadata (e.g., map geocoordinates, map source, and original vector data). Previous work on map processing is typically limited to a specific type of map and often relies on intensive manual work. In contrast, this thesis investigates a general approach that does not rely on any prior knowledge and requires minimal user effort to process heterogeneous raster maps. This approach includes automatic and supervised techniques to process raster maps for separating individual layers of geographic features from the maps and recognizing geographic features in the separated layers (i.e., detecting road intersections, generating and vectorizing road geometry, and recognizing text labels). The automatic technique eliminates user intervention by exploiting common map properties of how road lines and text labels are drawn in raster maps. For example, the road lines are elongated linear objects and the characters are small connected-objects. The supervised technique utilizes labels of road and text areas to handle complex raster maps, or maps with poor image quality, and can process a variety of raster maps with minimal user input. The results show that the general approach can handle raster maps with varying map complexity, color usage, and image quality. By matching extracted road intersections to another geospatial dataset, we can identify the geocoordinates of a raster map and further align the raster map, separated feature layers from the map, and recognized features from the layers with the geospatial dataset. The road vectorization and text recognition results outperform state-of-art commercial products, and with considerably less user input. The approach in this thesis allows us to make use of the geospatial information of heterogeneous maps locked in raster format.
Realistic Data-Driven Traffic Flow Animation Using Texture Synthesis.
Chao, Qianwen; Deng, Zhigang; Ren, Jiaping; Ye, Qianqian; Jin, Xiaogang
2018-02-01
We present a novel data-driven approach to populate virtual road networks with realistic traffic flows. Specifically, given a limited set of vehicle trajectories as the input samples, our approach first synthesizes a large set of vehicle trajectories. By taking the spatio-temporal information of traffic flows as a 2D texture, the generation of new traffic flows can be formulated as a texture synthesis process, which is solved by minimizing a newly developed traffic texture energy. The synthesized output captures the spatio-temporal dynamics of the input traffic flows, and the vehicle interactions in it strictly follow traffic rules. After that, we position the synthesized vehicle trajectory data to virtual road networks using a cage-based registration scheme, where a few traffic-specific constraints are enforced to maintain each vehicle's original spatial location and synchronize its motion in concert with its neighboring vehicles. Our approach is intuitive to control and scalable to the complexity of virtual road networks. We validated our approach through many experiments and paired comparison user studies.
NASA Astrophysics Data System (ADS)
Li, Jun; Qin, Qiming; Xie, Chao; Zhao, Yue
2012-10-01
The update frequency of digital road maps influences the quality of road-dependent services. However, digital road maps surveyed by probe vehicles or extracted from remotely sensed images still have a long updating circle and their cost remain high. With GPS technology and wireless communication technology maturing and their cost decreasing, floating car technology has been used in traffic monitoring and management, and the dynamic positioning data from floating cars become a new data source for updating road maps. In this paper, we aim to update digital road maps using the floating car data from China's National Commercial Vehicle Monitoring Platform, and present an incremental road network extraction method suitable for the platform's GPS data whose sampling frequency is low and which cover a large area. Based on both spatial and semantic relationships between a trajectory point and its associated road segment, the method classifies each trajectory point, and then merges every trajectory point into the candidate road network through the adding or modifying process according to its type. The road network is gradually updated until all trajectories have been processed. Finally, this method is applied in the updating process of major roads in North China and the experimental results reveal that it can accurately derive geometric information of roads under various scenes. This paper provides a highly-efficient, low-cost approach to update digital road maps.
"Dispersion modeling approaches for near road
Roadway design and roadside barriers can have significant effects on the dispersion of traffic-generated pollutants, especially in the near-road environment. Dispersion models that can accurately simulate these effects are needed to fully assess these impacts for a variety of app...
Quantifying the key factors that create road flooding : [tech summary].
DOT National Transportation Integrated Search
2013-01-01
Road fl ooding is a serious operational hazard for many low-lying areas across southern Louisiana. This hazard is especially acute for : the regions emergency evacuation routes, which must be accessible for safe evacuation prior to an approaching ...
Quantifying the key factors that create road flooding : research project capsule.
DOT National Transportation Integrated Search
2012-02-01
Road fl ooding is a serious operational hazard for low-lying areas of south Louisiana. This is : especially true for emergency evacuation routes, which must be accessible for coastal residents : evacuating ahead of an approaching hurricane or tropica...
Traffic Data Collection And Use In The Mexican Interurban Road Network
DOT National Transportation Integrated Search
2000-08-01
This paper describes how in the past, road construction in Mexico was linked more to sociopolitical concerns than to technical or economic studies to justify their construction. Now, new approaches are considered for the planning, construction, maint...
Møller, Anders Pape; Erritzøe, Helga; Erritzøe, Johannes
2011-04-01
Birds and other animals are frequently killed by cars, causing the death of many million individuals per year. Why some species are killed more often than others has never been investigated. In this work hypothesized that risk taking behavior may affect the probability of certain kinds of individuals being killed disproportionately often. Furthermore, behavior of individuals on roads, abundance, habitat preferences, breeding sociality, and health status may all potentially affect the risk of being killed on roads. We used information on the abundance of road kills and the abundance in the surrounding environment of 50 species of birds obtained during regular censuses in 2001-2006 in a rural site in Denmark to test these predictions. The frequency of road kills increased linearly with abundance, while the proportion of individuals sitting on the road or flying low across the road only explained little additional variation in frequency of road casualties. After having accounted for abundance, we found that species with a short flight distance and hence taking greater risks when approached by a potential cause of danger were killed disproportionately often. In addition, solitary species, species with a high prevalence of Plasmodium infection, and species with a large bursa of Fabricius for their body size had a high susceptibility to being killed by cars. These findings suggest that a range of different factors indicative of risk-taking behavior, visual acuity and health status cause certain bird species to be susceptible to casualties due to cars.
Countermeasures to driver fatigue: a review of public awareness campaigns and legal approaches.
Fletcher, A; McCulloch, K; Baulk, S D; Dawson, D
2005-10-01
Driver fatigue accounts for 10-40% of road crashes and is a critical area for public health. As other major road safety issues are more successfully managed, driver fatigue becomes proportionately more important. Both public awareness and legal developments have been slow to reach the same levels as for other road safety risks. The aim of this article is to review countermeasures for non-commercial drivers that are designed to reduce the likelihood of fatigue-related crashes through education and legislation. This review outlines information from a wide variety of sources including governments, road safety groups and the scientific literature. Educational and legislative approaches are discussed in terms of both their effectiveness and the associated implications for public health. Areas for improvement in education include personalising the risk to drivers and developing simple metrics for the self-assessment of fatigue. Legal implications should be more clearly defined and specific laws are needed to more effectively prosecute fatigued drivers who cause crashes. Additional research is needed to further investigate the efficacy of available countermeasures. Increasingly, road traffic injury is being discussed more broadly as a public health issue. However, the specific issue of driver fatigue still receives less attention than other main causes of road crashes, despite making a significant and comparable contribution to crash rates. Countries such as Australia and New Zealand have a responsibility to counter driver fatigue, as well as other causes of road crashes, and to further pursue improvements for the benefit of public health.
Automatic 3D high-fidelity traffic interchange modeling using 2D road GIS data
NASA Astrophysics Data System (ADS)
Wang, Jie; Shen, Yuzhong
2011-03-01
3D road models are widely used in many computer applications such as racing games and driving simulations. However, almost all high-fidelity 3D road models were generated manually by professional artists at the expense of intensive labor. There are very few existing methods for automatically generating 3D high-fidelity road networks, especially for those existing in the real world. Real road network contains various elements such as road segments, road intersections and traffic interchanges. Among them, traffic interchanges present the most challenges to model due to their complexity and the lack of height information (vertical position) of traffic interchanges in existing road GIS data. This paper proposes a novel approach that can automatically produce 3D high-fidelity road network models, including traffic interchange models, from real 2D road GIS data that mainly contain road centerline information. The proposed method consists of several steps. The raw road GIS data are first preprocessed to extract road network topology, merge redundant links, and classify road types. Then overlapped points in the interchanges are detected and their elevations are determined based on a set of level estimation rules. Parametric representations of the road centerlines are then generated through link segmentation and fitting, and they have the advantages of arbitrary levels of detail with reduced memory usage. Finally a set of civil engineering rules for road design (e.g., cross slope, superelevation) are selected and used to generate realistic road surfaces. In addition to traffic interchange modeling, the proposed method also applies to other more general road elements. Preliminary results show that the proposed method is highly effective and useful in many applications.
On-Road Validation of a Simplified Model for Estimating Real-World Fuel Economy: Preprint
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wood, Eric; Gonder, Jeff; Jehlik, Forrest
On-road fuel economy is known to vary significantly between individual trips in real-world driving conditions. This work introduces a methodology for rapidly simulating a specific vehicle's fuel economy over the wide range of real-world conditions experienced across the country. On-road test data collected using a highly instrumented vehicle is used to refine and validate this modeling approach. Model accuracy relative to on-road data collection is relevant to the estimation of 'off-cycle credits' that compensate for real-world fuel economy benefits that are not observed during certification testing on a chassis dynamometer.
On-Road Validation of a Simplified Model for Estimating Real-World Fuel Economy
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wood, Eric; Gonder, Jeffrey; Jehlik, Forrest
On-road fuel economy is known to vary significantly between individual trips in real-world driving conditions. This work introduces a methodology for rapidly simulating a specific vehicle's fuel economy over the wide range of real-world conditions experienced across the country. On-road test data collected using a highly instrumented vehicle is used to refine and validate this modeling approach. Here, model accuracy relative to on-road data collection is relevant to the estimation of 'off-cycle credits' that compensate for real-world fuel economy benefits that are not observed during certification testing on a chassis dynamometer.
On-Road Validation of a Simplified Model for Estimating Real-World Fuel Economy
Wood, Eric; Gonder, Jeffrey; Jehlik, Forrest
2017-03-28
On-road fuel economy is known to vary significantly between individual trips in real-world driving conditions. This work introduces a methodology for rapidly simulating a specific vehicle's fuel economy over the wide range of real-world conditions experienced across the country. On-road test data collected using a highly instrumented vehicle is used to refine and validate this modeling approach. Here, model accuracy relative to on-road data collection is relevant to the estimation of 'off-cycle credits' that compensate for real-world fuel economy benefits that are not observed during certification testing on a chassis dynamometer.
Measuring Tyre Rolling Noise at the Contact Patch
NASA Astrophysics Data System (ADS)
Kozak, P.; Matuszkova, R.; Radimsky, M.; Kudrna, J.
2017-06-01
This paper deals with noise generated by road traffic. A focus is concentrated solely on one of its sources related to tyre/road interaction referred as rolling noise. The paper states brief overview of various approaches and methods used to measure this particular source of road traffic noise. On the basis of literature reviews, a unique device has been designed. Development of the measuring device and possibilities of its usage are described in detail in this paper. Obtained results of noise measurements can then be used to design measures that increase safety and a lead to better comfort on the road.
Efficient road geometry identification from digital vector data
NASA Astrophysics Data System (ADS)
Andrášik, Richard; Bíl, Michal
2016-07-01
A new method for the automatic identification of road geometry from digital vector data is presented. The method is capable of efficiently identifying circular curves with their radii and tangents (straight sections). The average error of identification ranged from 0.01 to 1.30 % for precisely drawn data and 4.81 % in the case of actual road data with noise in the location of vertices. The results demonstrate that the proposed method is faster and more precise than commonly used techniques. This approach can be used by road administrators to complete their databases with information concerning the geometry of roads. It can also be utilized by transport engineers or traffic safety analysts to investigate the possible dependence of traffic accidents on road geometries. The method presented is applicable as well to railroads and rivers or other line features.
View looks east northeast (64°) along North Base Road, showing ...
View looks east northeast (64°) along North Base Road, showing North Base as it appears on approach by automobile. From left to right, one sees Building 4505 with its ancillary buildings; Building 4500, Control Tower; followed by Buildings 4402 (Hangar No. 2), 4401 (Hangar No. 1), and 4305 (Unicon Portable Hangar) with their respective ancillary structures. - Edwards Air Force Base, North Base, North Base Road, Boron, Kern County, CA
Variable Selection for Road Segmentation in Aerial Images
NASA Astrophysics Data System (ADS)
Warnke, S.; Bulatov, D.
2017-05-01
For extraction of road pixels from combined image and elevation data, Wegner et al. (2015) proposed classification of superpixels into road and non-road, after which a refinement of the classification results using minimum cost paths and non-local optimization methods took place. We believed that the variable set used for classification was to a certain extent suboptimal, because many variables were redundant while several features known as useful in Photogrammetry and Remote Sensing are missed. This motivated us to implement a variable selection approach which builds a model for classification using portions of training data and subsets of features, evaluates this model, updates the feature set, and terminates when a stopping criterion is satisfied. The choice of classifier is flexible; however, we tested the approach with Logistic Regression and Random Forests, and taylored the evaluation module to the chosen classifier. To guarantee a fair comparison, we kept the segment-based approach and most of the variables from the related work, but we extended them by additional, mostly higher-level features. Applying these superior features, removing the redundant ones, as well as using more accurately acquired 3D data allowed to keep stable or even to reduce the misclassification error in a challenging dataset.
DOT National Transportation Integrated Search
2014-12-01
The determination of warrants for bridge railing and approach guardrails is a : fundamental roadside safety issue. These are specialized roadside safety barriers that are : intended to capture and smoothly redirect errant vehicles that leave the road...
Road usage charge pilot project final evaluation report for Washington State participants.
DOT National Transportation Integrated Search
2013-05-01
This report provides a summary of evaluation results of Washingtons participation in : the Road Usage Charge Pilot Program (RUCPP). The RUCPP was a trial of various : approaches and technologies for motorists in the States of Washington, Oregon, a...
10. THIS PHOTOGRAPH, LOOKING NORTHWEST ALONG THE ROADWAY FROM THE ...
10. THIS PHOTOGRAPH, LOOKING NORTHWEST ALONG THE ROADWAY FROM THE SOUTH APPROACH, SHOWS THE CONCRETE PARAPET AS WELL AS LAYERS OF DETERIORATED ASPHALT AND CONCRETE. - Cement Plant Road Bridge, Spanning Leatherwood Creek on County Road 50 South, Bedford, Lawrence County, IN
North Dakota implementation of mechanistic-empirical pavement design guide (MEPDG).
DOT National Transportation Integrated Search
2014-12-01
North Dakota currently designs roads based on the AASHTO Design Guide procedure, which is based on : the empirical findings of the AASHTO Road Test of the late 1950s. However, limitations of the current : empirical approach have prompted AASHTO to mo...
The requirements and challenges in preventing of road traffic injury in Iran. A qualitative study.
Khorasani-Zavareh, Davoud; Mohammadi, Reza; Khankeh, Hamid Reza; Laflamme, Lucie; Bikmoradi, Ali; Haglund, Bo J A
2009-12-23
Road traffic injuries (RTIs) are a major public health problem, especially in low- and middle-income countries. Among middle-income countries, Iran has one of the highest mortality rates from RTIs. Action is critical to combat this major public health problem. Stakeholders involved in RTI control are of key importance and their perceptions of barriers and facilitators are a vital source of knowledge. The aim of this study was to explore barriers to the prevention of RTIs and provide appropriate suggestions for prevention, based on the perceptions of stakeholders, victims and road-users as regards RTIs. Thirty-eight semi-structured interviews were conducted with informants in the field of RTI prevention including: police officers; public health professionals; experts from the road administrators; representatives from the General Governor, the car industry, firefighters; experts from Emergency Medical Service and the Red Crescent; and some motorcyclists and car drivers as well as victims of RTIs. A qualitative approach using grounded theory method was employed to analyze the material gathered. The core variable was identified as "The lack of a system approach to road-user safety". The following barriers in relation to RTI prevention were identified as: human factors; transportation system; and organizational coordination. Suggestions for improvement included education (for the general public and targeted group training), more effective legislation, more rigorous law enforcement, improved engineering in road infrastructure, and an integrated organization to supervise and coordinate preventive activities. The major barriers identified in this study were human factors and efforts to change human behaviour were suggested by means of public education campaigns and stricter law enforcement. However, the lack of a system approach to RTI prevention was also an important concern. There is an urgent need for both an integrated system to coordinate RTI activities and prevention and a major change in stakeholders' attitudes towards RTI prevention. The focus of all activities should take place on road users' safety.
Behavior of amphibians on the road in response to car traffic
Mazerolle, M.J.; Huot, M.; Gravel, M.
2005-01-01
Nocturnal car traffic often results in amphibian casualties, especially during rainy nights. The behavior of amphibians presumably influences their vulnerability to mortality on the road, but this hypothesis remains untested. We investigated the behavioral response of individuals of six species of amphibians on roads when confronted by an approaching vehicle. We first conducted a field study consisting of 50 night-driving surveys over 4 yr during which we recorded the behavior (i.e., moving or immobile) of frogs, toads, tree frogs, and salamanders encountered on a 20-km stretch of road. In an effort to tease apart the effects of headlights and the sound of motors on amphibian behavior, we carried out a field experiment on a test road where we exposed individuals to different car-associated stimuli. Here, we tested the hypothesis that simultaneous exposure to headlights and the sound of a car motor would elicit a stronger response than exposure to a single stimulus or a control. Based on the observations of the 2767 individuals in the field survey, immobility was the most common response to the approach of a car (mean probability of 0.82 of remaining immobile); the response differed across species but depended on the season of the survey (May-June vs. July-September). Similarly, the 91 individuals included in the field experiment were more likely to move during the control treatment than during any of the car-associated treatments. The combined stimuli elicited the strongest response, followed by the headlights-only and the motor-only treatments. Spring peepers (Pseudacris crucifer) tended to move more often than the other species we tested in the field experiment, which suggests they spend less time on the road and are less vulnerable to traffic mortality than other species. Both the field survey and field experiment consistently indicated that amphibians tend to remain immobile at the approach of a vehicle. This behavior highlights the vulnerability of amphibians to road traffic and should be considered in measures to mitigate road impacts. ?? 2005 by The Herpetologists' League, Inc.
Road user behaviour changes following a self-explaining roads intervention.
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.
NASA Astrophysics Data System (ADS)
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 approach is relevant and accurate as it can handle the most frequent layouts of dashed lines. Some issues, for instance, such as the relative weighting of both terms of the energy are also discussed in the conclusion.
NASA Astrophysics Data System (ADS)
Themistocleous, Kyriacos; Neocleous, Kyriacos; Pilakoutas, Kypros; Hadjimitsis, Diofantos G.
2014-08-01
The predominant approach for conducting road condition surveys and analyses is still largely based on extensive field observations. However, visual assessment alone cannot identify the actual extent and severity of damage. New non-invasive and cost-effective non-destructive (NDT) remote sensing technologies can be used to monitor road pavements across their life cycle, including remotely sensed aerial and satellite visual and thermal image (AI) data, Unmanned Aerial Vehicles (UAVs), Spectroscopy and Ground Penetrating Radar (GRP). These non-contact techniques can be used to obtain surface and sub-surface information about damage in road pavements, including the crack depth, and in-depth structural failure. Thus, a smart and cost-effective methodology is required that integrates several of these non-destructive/ no-contact techniques for the damage assessment and monitoring at different levels. This paper presents an overview of how an integration of the above technologies can be used to conduct detailed road condition surveys. The proposed approach can also be used to predict the future needs for road maintenance; this information is proven to be valuable to a strategic decision making tools that optimizes maintenance based on resources and environmental issues.
Hong, Nian; Zhu, Panfeng; Liu, An
2017-12-01
Urban road stormwater is an alternative water resource to mitigate water shortage issues in the worldwide. Heavy metals deposited (build-up) on urban road surface can enter road stormwater runoff, undermining stormwater reuse safety. As heavy metal build-up loads perform high variabilities in terms of spatial distribution and is strongly influenced by surrounding land uses, it is essential to develop an approach to identify hot-spots where stormwater runoff could include high heavy metal concentrations and hence cannot be reused if it is not properly treated. This study developed a robust modelling approach to estimating heavy metal build-up loads on urban roads using land use fractions (representing percentages of land uses within a given area) by an artificial neural network (ANN) model technique. Based on the modelling results, a series of heavy metal load spatial distribution maps and a comprehensive ecological risk map were generated. These maps provided a visualization platform to identify priority areas where the stormwater can be safely reused. Additionally, these maps can be utilized as an urban land use planning tool in the context of effective stormwater reuse strategy implementation. Copyright © 2017 Elsevier Ltd. All rights reserved.
Road extraction from aerial images using a region competition algorithm.
Amo, Miriam; Martínez, Fernando; Torre, Margarita
2006-05-01
In this paper, we present a user-guided method based on the region competition algorithm to extract roads, and therefore we also provide some clues concerning the placement of the points required by the algorithm. The initial points are analyzed in order to find out whether it is necessary to add more initial points, and this process will be based on image information. Not only is the algorithm able to obtain the road centerline, but it also recovers the road sides. An initial simple model is deformed by using region growing techniques to obtain a rough road approximation. This model will be refined by region competition. The result of this approach is that it delivers the simplest output vector information, fully recovering the road details as they are on the image, without performing any kind of symbolization. Therefore, we tried to refine a general road model by using a reliable method to detect transitions between regions. This method is proposed in order to obtain information for feeding large-scale Geographic Information System.
A participatory sensing approach to characterize ride quality
NASA Astrophysics Data System (ADS)
Bridgelall, Raj
2014-03-01
Rough roads increase vehicle operation and road maintenance costs. Consequently, transportation agencies spend a significant portion of their budgets on ride-quality characterization to forecast maintenance needs. The ubiquity of smartphones and social media, and the emergence of a connected vehicle environment present lucrative opportunities for cost-reduction and continuous, network-wide, ride-quality characterization. However, there is a lack of models to transform inertial and position information from voluminous data flows into indices that transportation agencies currently use. This work expands on theories of the Road Impact Factor introduced in previous research. The index characterizes road roughness by aggregating connected vehicle data and reporting roughness in direct proportion to the International Roughness Index. Their theoretical relationships are developed, and a case study is presented to compare the relative data quality from an inertial profiler and a regular passenger vehicle. Results demonstrate that the approach is a viable alternative to existing models that require substantially more resources and provide less network coverage. One significant benefit of the participatory sensing approach is that transportation agencies can monitor all network facilities continuously to locate distress symptoms, such as frost heaves, that appear and disappear between ride assessment cycles. Another benefit of the approach is continuous monitoring of all high-risk intersections such as rail grade crossings to better understand the relationship between ride-quality and traffic safety.
NASA Astrophysics Data System (ADS)
Yang, X. F.; Liu, H.; Man, H. Y.; He, K. B.
2014-06-01
Mobile source emission inventories serve as critical input for atmospheric chemical transport models, which are used to simulate air quality and understand the role of mobile source emissions. The significance of mobile sources is even more important in China because the country has the largest vehicle population in the world, and that population continues to grow rapidly. Estimating emissions from diesel trucks is a critical work in mobile source emission inventories due to the importance and difficulties associated with estimating emissions from diesel trucks. Although diesel trucks are major contributors of nitrogen oxide (NOx) and primary particulate matter smaller than 2.5 μm (PM2.5), there are still more obstacles on the existing estimation of diesel truck emissions compared with that of cars; long-range freight transportation activities are complicated, and much of the basic data remain unclear. Most of existing inventories were based on local registration number. However, according to our research, a large number of trucks are conducting long-distance inter-city or inter province transportation. Instead of the local registration number based approach, a road emission intensity-based (REIB) approach is introduced in this research. To provide efficient data for the REIB approach, 1060 questionnaire responses and approximately 1.7 million valid seconds of onboard GPS monitoring data were collected. Both the questionnaire answers and GPS monitoring results indicated that the driving conditions on different types of road have significant impacts on the emission levels of freight trucks. We present estimated emissions of NOx and primary PM2.5 from diesel freight trucks for China in 2011. Using the REIB approach, the activity level and distribution data are obtained from the questionnaire answers. Emission factors are calculated with the International Vehicle Emission (IVE) model that interpolated local on-board measurement results in China according to the GPS monitoring data on different roads. Depending on the results in this research, the largest differences among the emission factors (in g km-1) on different roads exceed 70 and 50% for NOx and PM2.5, respectively. The differences were caused by different driving conditions that we monitored via GPS. The estimated NOx and PM2.5 emissions from diesel freight trucks in China were 5.0 (4.8-7.2) million t and 0.20 (0.17-0.22) million t, respectively, via the REIB approach in 2011. Another implication of this research is that different road infrastructure would have different impacts for NOx and PM2.5 emissions. A region with more inter-city freeways or national roads tends to have more NOx emissions, while urban streets play a more important role in primary PM2.5 emissions from freight trucks. Compared with former studies, which allocate emissions according to local truck registration number and neglect inter-region long distance transport trips, the REIB approach has advantages regarding the allocation of diesel truck emissions into the provinces. Furthermore, the different driving conditions on the different roads types are no longer overlooked with this approach.
NASA Astrophysics Data System (ADS)
Alshehhi, Rasha; Marpu, Prashanth Reddy
2017-04-01
Extraction of road networks in urban areas from remotely sensed imagery plays an important role in many urban applications (e.g. road navigation, geometric correction of urban remote sensing images, updating geographic information systems, etc.). It is normally difficult to accurately differentiate road from its background due to the complex geometry of the buildings and the acquisition geometry of the sensor. In this paper, we present a new method for extracting roads from high-resolution imagery based on hierarchical graph-based image segmentation. The proposed method consists of: 1. Extracting features (e.g., using Gabor and morphological filtering) to enhance the contrast between road and non-road pixels, 2. Graph-based segmentation consisting of (i) Constructing a graph representation of the image based on initial segmentation and (ii) Hierarchical merging and splitting of image segments based on color and shape features, and 3. Post-processing to remove irregularities in the extracted road segments. Experiments are conducted on three challenging datasets of high-resolution images to demonstrate the proposed method and compare with other similar approaches. The results demonstrate the validity and superior performance of the proposed method for road extraction in urban areas.
A scenario planning approach for disasters on Swiss road network
NASA Astrophysics Data System (ADS)
Mendes, G. A.; Axhausen, K. W.; Andrade, J. S.; Herrmann, H. J.
2014-05-01
We study a vehicular traffic scenario on Swiss roads in an emergency situation, calculating how sequentially roads block due to excessive traffic load until global collapse (gridlock) occurs and in this way displays the fragilities of the system. We used a database from Bundesamt für Raumentwicklung which contains length and maximum allowed speed of all roads in Switzerland. The present work could be interesting for government agencies in planning and managing for emergency logistics for a country or a big city. The model used to generate the flux on the Swiss road network was proposed by Mendes et al. [Physica A 391, 362 (2012)]. It is based on the conservation of the number of vehicles and allows for an easy and fast way to follow the formation of traffic jams in large systems. We also analyze the difference between a nonlinear and a linear model and the distribution of fluxes on the Swiss road.
A user exposure based approach for non-structural road network vulnerability analysis
Jin, Lei; Wang, Haizhong; Yu, Le; Liu, Lin
2017-01-01
Aiming at the dense urban road network vulnerability without structural negative consequences, this paper proposes a novel non-structural road network vulnerability analysis framework. Three aspects of the framework are mainly described: (i) the rationality of non-structural road network vulnerability, (ii) the metrics for negative consequences accounting for variant road conditions, and (iii) the introduction of a new vulnerability index based on user exposure. Based on the proposed methodology, a case study in the Sioux Falls network which was usually threatened by regular heavy snow during wintertime is detailedly discussed. The vulnerability ranking of links of Sioux Falls network with respect to heavy snow scenario is identified. As a result of non-structural consequences accompanied by conceivable degeneration of network, there are significant increases in generalized travel time costs which are measurements for “emotionally hurt” of topological road network. PMID:29176832
Singh, Gyanendra; Sachdeva, S N; Pal, Mahesh
2016-11-01
This work examines the application of M5 model tree and conventionally used fixed/random effect negative binomial (FENB/RENB) regression models for accident prediction on non-urban sections of highway in Haryana (India). Road accident data for a period of 2-6 years on different sections of 8 National and State Highways in Haryana was collected from police records. Data related to road geometry, traffic and road environment related variables was collected through field studies. Total two hundred and twenty two data points were gathered by dividing highways into sections with certain uniform geometric characteristics. For prediction of accident frequencies using fifteen input parameters, two modeling approaches: FENB/RENB regression and M5 model tree were used. Results suggest that both models perform comparably well in terms of correlation coefficient and root mean square error values. M5 model tree provides simple linear equations that are easy to interpret and provide better insight, indicating that this approach can effectively be used as an alternative to RENB approach if the sole purpose is to predict motor vehicle crashes. Sensitivity analysis using M5 model tree also suggests that its results reflect the physical conditions. Both models clearly indicate that to improve safety on Indian highways minor accesses to the highways need to be properly designed and controlled, the service roads to be made functional and dispersion of speeds is to be brought down. Copyright © 2016 Elsevier Ltd. All rights reserved.
A model-based approach to monitor complex road-vehicle interactions through first principles
NASA Astrophysics Data System (ADS)
Chakravarty, T.; Srinivasarengan, K.; Roy, S.; Bilal, S.; Balamuralidhar, P.
2013-02-01
The increasing availability of portable computing devices and their interaction with physical systems ask for designing compact models and simulations to understand and characterize such interactions. For instance, monitoring a road's grade using accelerometer stationed inside a moving ground vehicle is an emerging trend in city administration. Typically the focus has largely been to develop algorithms to articulate meaning from that. But, the experimentation cannot provide with an exhaustive analysis of all scenarios and the characteristics of them. We propose an approach of modeling these interactions of physical systems with gadgets through first principles, in a compact manner to focus on limited number of interactions. We derive an approach to model the vehicle interaction with a pothole on a road, a specific case, but allowing for selectable car parameters like natural damped frequency, tire size etc, thus generalizing it. Different road profiles are also created to represent rough road with sharp irregularities. These act as excitation to the moving vehicle and the interaction is computed to determine the vertical/ lateral vibration of the system i.e vehicle with sensors using joint time-frequency signal analysis methods. The simulation is compared with experimental data for validation. We show some directions as to how simulation of such models can reveal different characteristics of the interaction through analysis of their frequency spectrum. It is envisioned that the proposed models will get enriched further as and when large data set of real life data is captured and appropriate sensitivity analysis is done.
Improving drivers' knowledge of road rules using digital games.
Li, Qing; Tay, Richard
2014-04-01
Although a proficient knowledge of the road rules is important to safe driving, many drivers do not retain the knowledge acquired after they have obtained their licenses. Hence, more innovative and appealing methods are needed to improve drivers' knowledge of the road rules. This study examines the effect of game based learning on drivers' knowledge acquisition and retention. We find that playing an entertaining game that is designed to impart knowledge of the road rules not only improves players' knowledge but also helps them retain such knowledge. Hence, learning by gaming appears to be a promising learning approach for driver education. Copyright © 2013 Elsevier Ltd. All rights reserved.
Network-level accident-mapping: Distance based pattern matching using artificial neural network.
Deka, Lipika; Quddus, Mohammed
2014-04-01
The objective of an accident-mapping algorithm is to snap traffic accidents onto the correct road segments. Assigning accidents onto the correct segments facilitate to robustly carry out some key analyses in accident research including the identification of accident hot-spots, network-level risk mapping and segment-level accident risk modelling. Existing risk mapping algorithms have some severe limitations: (i) they are not easily 'transferable' as the algorithms are specific to given accident datasets; (ii) they do not perform well in all road-network environments such as in areas of dense road network; and (iii) the methods used do not perform well in addressing inaccuracies inherent in and type of road environment. The purpose of this paper is to develop a new accident mapping algorithm based on the common variables observed in most accident databases (e.g. road name and type, direction of vehicle movement before the accident and recorded accident location). The challenges here are to: (i) develop a method that takes into account uncertainties inherent to the recorded traffic accident data and the underlying digital road network data, (ii) accurately determine the type and proportion of inaccuracies, and (iii) develop a robust algorithm that can be adapted for any accident set and road network of varying complexity. In order to overcome these challenges, a distance based pattern-matching approach is used to identify the correct road segment. This is based on vectors containing feature values that are common in the accident data and the network data. Since each feature does not contribute equally towards the identification of the correct road segments, an ANN approach using the single-layer perceptron is used to assist in "learning" the relative importance of each feature in the distance calculation and hence the correct link identification. The performance of the developed algorithm was evaluated based on a reference accident dataset from the UK confirming that the accuracy is much better than other methods. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.
Lafont, Sylviane; Amoros, Emmanuelle; Gadegbeku, Blandine; Chiron, Mireille; Laumon, Bernard
2008-01-01
One of the concerns in road safety is the threat older drivers may pose to other road users. Using the rate of lost life years, the present study provides a public health approach to quantify this potential threat. A total of 1570686 motorised vehicle drivers or motorcycle riders and 652246 non-drivers, i.e. vehicle passengers, pedestrians and cyclists involved in injury crashes in France between 1996 and 2004, were included in a population based cross-sectional study. Fatality rates and rate of lost life years for each crash-involved driver age class were calculated for the drivers themselves and for other road users. The study has shown a significant reduction in the rate of lost life years for crash-involved other road users (whether passengers, pedestrians, cyclists or opposing drivers) as driver age increases. Other road users lost half as many years of life when involved in crashes with drivers aged over 85 than with drivers under 65 (1.26 and 2.32 per 100 expected remaining life years, respectively). Our findings suggest that among road users involved in injury crashes, older drivers are less dangerous for the other road users. By attributing other road users' lost life years to each driver age, this study represents a new contribution to the debate about ageing and road safety.
Hayati, Elyas; Majnounian, Baris; Abdi, Ehsan; Sessions, John; Makhdoum, Majid
2013-02-01
Changes in forest landscapes resulting from road construction have increased remarkably in the last few years. On the other hand, the sustainable management of forest resources can only be achieved through a well-organized road network. In order to minimize the environmental impacts of forest roads, forest road managers must design the road network efficiently and environmentally as well. Efficient planning methodologies can assist forest road managers in considering the technical, economic, and environmental factors that affect forest road planning. This paper describes a three-stage methodology using the Delphi method for selecting the important criteria, the Analytic Hierarchy Process for obtaining the relative importance of the criteria, and finally, a spatial multi-criteria evaluation in a geographic information system (GIS) environment for identifying the lowest-impact road network alternative. Results of the Delphi method revealed that ground slope, lithology, distance from stream network, distance from faults, landslide susceptibility, erosion susceptibility, geology, and soil texture are the most important criteria for forest road planning in the study area. The suitability map for road planning was then obtained by combining the fuzzy map layers of these criteria with respect to their weights. Nine road network alternatives were designed using PEGGER, an ArcView GIS extension, and finally, their values were extracted from the suitability map. Results showed that the methodology was useful for identifying road that met environmental and cost considerations. Based on this work, we suggest future work in forest road planning using multi-criteria evaluation and decision making be considered in other regions and that the road planning criteria identified in this study may be useful.
A model to identify high crash road segments with the dynamic segmentation method.
Boroujerdian, Amin Mirza; Saffarzadeh, Mahmoud; Yousefi, Hassan; Ghassemian, Hassan
2014-12-01
Currently, high social and economic costs in addition to physical and mental consequences put road safety among most important issues. This paper aims at presenting a novel approach, capable of identifying the location as well as the length of high crash road segments. It focuses on the location of accidents occurred along the road and their effective regions. In other words, due to applicability and budget limitations in improving safety of road segments, it is not possible to recognize all high crash road segments. Therefore, it is of utmost importance to identify high crash road segments and their real length to be able to prioritize the safety improvement in roads. In this paper, after evaluating deficiencies of the current road segmentation models, different kinds of errors caused by these methods are addressed. One of the main deficiencies of these models is that they can not identify the length of high crash road segments. In this paper, identifying the length of high crash road segments (corresponding to the arrangement of accidents along the road) is achieved by converting accident data to the road response signal of through traffic with a dynamic model based on the wavelet theory. The significant advantage of the presented method is multi-scale segmentation. In other words, this model identifies high crash road segments with different lengths and also it can recognize small segments within long segments. Applying the presented model into a real case for identifying 10-20 percent of high crash road segment showed an improvement of 25-38 percent in relative to the existing methods. Copyright © 2014 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Jiménez-Redondo, Noemi; Calle-Cordón, Alvaro; Kandler, Ute; Simroth, Axel; Morales, Francisco J.; Reyes, Antonio; Odelius, Johan; Thaduri, Aditya; Morgado, Joao; Duarte, Emmanuele
2017-09-01
The on-going H2020 project INFRALERT aims to increase rail and road infrastructure capacity in the current framework of increased transportation demand by developing and deploying solutions to optimise maintenance interventions planning. It includes two real pilots for road and railways infrastructure. INFRALERT develops an ICT platform (the expert-based Infrastructure Management System, eIMS) which follows a modular approach including several expert-based toolkits. This paper presents the methodologies and preliminary results of the toolkits for i) nowcasting and forecasting of asset condition, ii) alert generation, iii) RAMS & LCC analysis and iv) decision support. The results of these toolkits in a meshed road network in Portugal under the jurisdiction of Infraestruturas de Portugal (IP) are presented showing the capabilities of the approaches.
1. LOOKING DOWNSTREAM (NORTHEAST) ALONG WINTER'S RUN TOWARD THE MITCHELL'S ...
1. LOOKING DOWNSTREAM (NORTHEAST) ALONG WINTER'S RUN TOWARD THE MITCHELL'S MILL BRIDGE, SHOWING THE SETTING OF THE BRIDGE. CARRS MILL ROAD APPROACHES THE BRIDGE FROM THE SOUTH, ON THE RIGHT. - Mitchell's Mill Bridge, Spanning Winter's Run on Carrs Mill Road, west of Bel Air, Bel Air, Harford County, MD
Walking in Balance on the Red Road.
ERIC Educational Resources Information Center
Thin Elk, Gene
1993-01-01
Native American who entered treatment for alcohol abuse and found that conventional cures did not address cultural clash of being Indian in Eurocentric society describes alcohol prevention and treatment program rooted in traditional Indian values and ceremonies. Describes "The Red Road," holistic approach which uses culture as therapy and…
One proposed method for reducing exposure to mobile-source air pollution is the construction or preservation of vegetation barriers between major roads and nearby populations. This study combined stationary and mobile monitoring approaches to determine the effects of an existing,...
Using medico-legal data to investigate fatal older road user crash circumstances and risk factors.
Koppel, Sjaan; Bugeja, Lyndal; Smith, Daisy; Lamb, Ashne; Dwyer, Jeremy; Fitzharris, Michael; Newstead, Stuart; D'Elia, Angelo; Charlton, Judith
2018-02-17
This study used medico-legal data to investigate fatal older road user (ORU, aged 65 years and older) crash circumstances and risk factors relating to 4 key components of the Safe System approach (e.g., roads and roadsides, vehicles, road users, and speeds) to identify areas of priority for targeted prevention activity. The Coroners' Court of Victoria's (CCOV) Surveillance Database was searched to identify and describe the frequency and rate per 100,000 population of fatal ORU crashes in the Australian state of Victoria for 2013-2014. Information relating to the deceased ORU, crash characteristics and circumstances, and risk factors was extracted and analyzed. One hundred and thirty-eight unintentional fatal ORU crashes were identified in the CCOV Surveillance Database. Of these fatal ORU crashes, most involved older drivers (44%), followed by older pedestrians (32%), older passengers (17%), older pedal cyclists (4%), older motorcyclists (1%), and older mobility scooter users (1%). The average annual rate of fatal ORU crashes per 100,000 population was 8.1 (95% confidence interval [CI], 6.0-10.2). In terms of the crash characteristics and circumstances, most fatal ORU crashes involved a counterpart (98%), of which the majority were passenger cars (50%) or fixed/stationary objects (25%), including trees (46%) or embankments (23%). In addition, most fatal ORU crashes occurred close to home (73%), on-road (87%), on roads that were paved (94%), on roads with light traffic volume (37%), and during low-risk conditions: between 12 p.m. and 6 p.m. (44%), on weekdays (80%), during daylight (75%), and under dry/clear conditions (81%). Road user (RU) error was identified by the police and/or the coroner for the majority of fatal crashes (55%), with a significant proportion of deceased ORUs deemed to have failed to yield (54%) or misjudged (41%). RU error was the most significant factor identified in fatal ORU crashes, which suggests that there is a limited capacity of the road system to fully accommodate RU errors. Initiatives related to safer roads and roadsides, vehicles, speed zones, as well as behavioral approaches are key areas of priority for targeted activity to prevent fatal ORU crashes in the future.
Regional analysis of the effect of paved roads on sodium and chloride in lakes.
Kelting, Daniel L; Laxson, Corey L; Yerger, Elizabeth C
2012-05-15
Salinization of surface water from sodium chloride (road salt) applied to paved roads is a widely recognized environmental concern in the northern hemisphere, yet practical information to improve winter road management to reduce the environmental impacts of this deicer is lacking. The purpose of our study was to provide such information by developing baseline concentrations for sodium and chloride for lakes in watersheds without paved roads, and then determining the relationship between these ions and density, type, and proximity of paved roads to shoreline. We used average summer (June-September) sodium and chloride data for 138 lakes combined in a watershed based analysis of paved road networks in the Adirondack Park of New York, U.S.A. The watersheds used in our study represented a broad range in paved road density and type, 56 of which had no paved roads. Median lake sodium and chloride concentrations in these 56 watersheds averaged 0.55 and 0.24 mg/L, respectively. In contrast, the median sodium and chloride concentrations for the 82 lakes in watersheds with paved roads were 3.60 and 7.22 mg/L, respectively. Paved road density (lane-km/km(2)) was positively correlated with sodium and chloride concentrations, but only state roads were significantly correlated with sodium and chloride while local roads were not. State road density alone explained 84 percent of the variation in both ions. We also successfully modeled the relationship between road proximity to shoreline and sodium and chloride concentrations in lakes, which allowed us to identify sections of road that contributed more to explaining the variation in sodium and chloride in lakes. This model and our approach could be used as part of larger efforts to identify environmentally sensitive areas where alternative winter road management treatments should be applied. Copyright © 2012 Elsevier Ltd. All rights reserved.
Joint road safety operations in tunnels and open roads
NASA Astrophysics Data System (ADS)
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.
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.
The role of roadsides in plant invasions: a demographic approach.
Christen, Douglas; Matlack, Glenn
2006-04-01
Non-native plant species are common along roadsides, but presence does not necessarily indicate spread along the road axis. Roadsides may serve merely as habitat for a species spreading independently of roads. The potential conduit function of roads depends on the habitat specificity of the spreading species, its dispersal range relative to the spacing of roads in the landscape, and the relative importance of long- and short-range dispersal. We describe a demographic model of the road x species interaction and suggest methods of assessing conduit function in the field based on the model results. A species limited to roadside habitat will be constrained to spread along the road axis unless its long-range dispersal is sufficient to carry it across the intervening unfavorable area to another road. It will propagate along a road corridor at a rate determined by the scale of short-range dispersal. Effective management of an invasion requires distinguishing between the habitat and conduit functions, a distinction difficult to make with only snapshot data. Invasions can be reconstructed by several methods, but none is totally satisfactory. We suggest comparing stem distributions on transects parallel and perpendicular to the road axis, and beside the road, and away from it, with an idealized Gaussian curve. Such comparisons would allow discrimination between pattern determined by habitat suitability and pattern reflecting random and facilitated dispersal.
User costs as one of main advantages of precast concrete application in highway construction
NASA Astrophysics Data System (ADS)
Tomek, Radan
2017-09-01
Road user cost primarily refer to the monetized components of road (re)construction impacts, such as the user delay costs, vehicle operating costs, crash costs and emission costs. Objective of this paper is to analyze and appraise the advantages and benefits of the innovative prefabrication approach in contrast to traditional cast-in-place construction method. The goal is to reduce these additional costs borne by motorists and the community at-large as a result of road construction activity to their minimum through application of the prefabrication. Assessing two basic possible approaches to highway infrastructure construction - casting the road pavements and structures either in place or precast off the site - it can be concluded that the initial capital investment costs do not vary much. Substantial differences can be recognized when comparing their life-cycle costs and an extent to which their construction process affects the public, environment and the local economy. Prefabrication of any structure component off-site offers major construction time and user cost savings in comparison with the traditional cast-in-place methods of construction. Precast prestressed road pavements’ technology and precasting bridges’ parts and elements offers dramatic increase in durability, while it also substantially decreases construction time and resulting user costs.
Robbins, Chloe Jade; Chapman, Peter
2018-06-01
The current study investigated the behavior and visual attention of two groups of drivers with differing pedal cycling experience (pedal cyclists and nonpedal cyclists) towards vulnerable road users at junctions in a driving simulator. Pedal cyclists and motorcyclists are involved in a disproportionate number of crashes given the distance they travel, with a high proportion of these crashes occurring at junctions. Many studies have found that car drivers who also hold a motorcycle license have increased awareness towards motorcycles. The task involved approaching a T-junction and turning right when it was deemed to be safe. In Study 1, the junction was controlled by a give way sign, and in Study 2, the junction was controlled by a stop sign. Each T-junction contained a target vehicle (car, motorcycle, or pedal cycle), approaching from a near, medium, or far distance from the junction. Participants did not look at pedal cycles approaching from a far distance for as long as they looked at approaching motorcycles and cars, despite all vehicles travelling at identical speeds. No differences were found between pedal cyclists and nonpedal cyclists on any visual attention measures, indicating that pedal cycling experience was not associated with differences in drivers' attention toward pedal cycles. Findings have implications for road safety, demonstrating subtle differences in drivers' everyday visual attention toward differing vehicle types. This research has the potential to inform the development of in-car technical assistive systems, improving the safety of vulnerable road users at junctions.
Guttman, Nurit
2015-11-01
Communication campaigns are employed as an important tool to promote road safety practices. Researchers maintain road safety communication campaigns are more effective when their persuasive appeals, which are central to their communicative strategy, are based on explicit theoretical frameworks. This study's main objectives were to develop a detailed categorization of persuasive appeals used in road safety communication campaigns that differentiate between appeals that appear to be similar but differ conceptually, and to indicate the advantages, limitations and ethical issues associated with each type, drawing on behavior change theories. Materials from over 300 campaigns were obtained from 41 countries, mainly using road safety organizations' websites. Drawing on the literature, five types of main approaches were identified, and the analysis yielded a more detailed categorizations of appeals within these general categories. The analysis points to advantages, limitations, ethical issues and challenges in using different types of appeals. The discussion summarizes challenges in designing persuasive-appeals for road safety communication campaigns. Copyright © 2015 Elsevier Ltd. All rights reserved.
Guttman, Nurit
2016-12-01
Communication campaigns are employed as an important tool to promote road safety practices. Researchers maintain road safety communication campaigns are more effective when their persuasive appeals, which are central to their communicative strategy, are based on explicit theoretical frameworks. This study's main objectives were to develop a detailed categorization of persuasive appeals used in road safety communication campaigns that differentiate between appeals that appear to be similar but differ conceptually, and to indicate the advantages, limitations and ethical issues associated with each type, drawing on behavior change theories. Materials from over 300 campaigns were obtained from 41 countries, mainly using road safety organizations' websites. Drawing on the literature, five types of main approaches were identified, and the analysis yielded a more detailed categorizations of appeals within these general categories. The analysis points to advantages, limitations, ethical issues and challenges in using different types of appeals. The discussion summarizes challenges in designing persuasive-appeals for road safety communication campaigns. Copyright © 2015 Elsevier Ltd. All rights reserved.
3D road marking reconstruction from street-level calibrated stereo pairs
NASA Astrophysics Data System (ADS)
Soheilian, Bahman; Paparoditis, Nicolas; Boldo, Didier
This paper presents an automatic approach to road marking reconstruction using stereo pairs acquired by a mobile mapping system in a dense urban area. Two types of road markings were studied: zebra crossings (crosswalks) and dashed lines. These two types of road markings consist of strips having known shape and size. These geometric specifications are used to constrain the recognition of strips. In both cases (i.e. zebra crossings and dashed lines), the reconstruction method consists of three main steps. The first step extracts edge points from the left and right images of a stereo pair and computes 3D linked edges using a matching process. The second step comprises a filtering process that uses the known geometric specifications of road marking objects. The goal is to preserve linked edges that can plausibly belong to road markings and to filter others out. The final step uses the remaining linked edges to fit a theoretical model to the data. The method developed has been used for processing a large number of images. Road markings are successfully and precisely reconstructed in dense urban areas under real traffic conditions.
Road accident rates: strategies and programmes for improving road traffic safety.
Goniewicz, K; Goniewicz, M; Pawłowski, W; Fiedor, P
2016-08-01
Nowadays, the problem of road accident rates is one of the most important health and social policy issues concerning the countries in all continents. Each year, nearly 1.3 million people worldwide lose their life on roads, and 20-50 million sustain severe injuries, the majority of which require long-term treatment. The objective of the study was to identify the most frequent, constantly occurring causes of road accidents, as well as outline actions constituting a basis for the strategies and programmes aiming at improving traffic safety on local and global levels. Comparative analysis of literature concerning road safety was performed, confirming that although road accidents had a varied and frequently complex background, their causes have changed only to a small degree over the years. The causes include: lack of control and enforcement concerning implementation of traffic regulation (primarily driving at excessive speed, driving under the influence of alcohol, and not respecting the rights of other road users (mainly pedestrians and cyclists), lack of appropriate infrastructure and unroadworthy vehicles. The number of fatal accidents and severe injuries, resulting from road accidents, may be reduced through applying an integrated approach to safety on roads. The strategies and programmes for improving road traffic should include the following measures: reducing the risk of exposure to an accident, prevention of accidents, reduction in bodily injuries sustained in accidents, and reduction of the effects of injuries by improvement of post-accident medical care.
NASA Astrophysics Data System (ADS)
Litvaitis, John A.; Reed, Gregory C.; Carroll, Rory P.; Litvaitis, Marian K.; Tash, Jeffrey; Mahard, Tyler; Broman, Derek J. A.; Callahan, Catherine; Ellingwood, Mark
2015-06-01
We are using bobcats ( Lynx rufus) as a model organism to examine how roads affect the abundance, distribution, and genetic structure of a wide-ranging carnivore. First, we compared the distribution of bobcat-vehicle collisions to road density and then estimated collision probabilities for specific landscapes using a moving window with road-specific traffic volume. Next, we obtained incidental observations of bobcats from the public, camera-trap detections, and locations of bobcats equipped with GPS collars to examine habitat selection. These data were used to generate a cost-surface map to investigate potential barrier effects of roads. Finally, we have begun an examination of genetic structure of bobcat populations in relation to major road networks. Distribution of vehicle-killed bobcats was correlated with road density, especially state and interstate highways. Collision models suggested that some regions may function as demographic sinks. Simulated movements in the context of the cost-surface map indicated that some major roads may be barriers. These patterns were supported by the genetic structure of bobcats. The sharpest divisions among genetically distinct demes occurred along natural barriers (mountains and large lakes) and in road-dense regions. In conclusion, our study has demonstrated the utility of using bobcats as a model organism to understand the variety of threats that roads pose to a wide-ranging species. Bobcats may also be useful as one of a group of focal species while developing approaches to maintain existing connectivity or mitigate the negative effects of roads.
Litvaitis, John A; Reed, Gregory C; Carroll, Rory P; Litvaitis, Marian K; Tash, Jeffrey; Mahard, Tyler; Broman, Derek J A; Callahan, Catherine; Ellingwood, Mark
2015-06-01
We are using bobcats (Lynx rufus) as a model organism to examine how roads affect the abundance, distribution, and genetic structure of a wide-ranging carnivore. First, we compared the distribution of bobcat-vehicle collisions to road density and then estimated collision probabilities for specific landscapes using a moving window with road-specific traffic volume. Next, we obtained incidental observations of bobcats from the public, camera-trap detections, and locations of bobcats equipped with GPS collars to examine habitat selection. These data were used to generate a cost-surface map to investigate potential barrier effects of roads. Finally, we have begun an examination of genetic structure of bobcat populations in relation to major road networks. Distribution of vehicle-killed bobcats was correlated with road density, especially state and interstate highways. Collision models suggested that some regions may function as demographic sinks. Simulated movements in the context of the cost-surface map indicated that some major roads may be barriers. These patterns were supported by the genetic structure of bobcats. The sharpest divisions among genetically distinct demes occurred along natural barriers (mountains and large lakes) and in road-dense regions. In conclusion, our study has demonstrated the utility of using bobcats as a model organism to understand the variety of threats that roads pose to a wide-ranging species. Bobcats may also be useful as one of a group of focal species while developing approaches to maintain existing connectivity or mitigate the negative effects of roads.
Modeling and Density Estimation of an Urban Freeway Network Based on Dynamic Graph Hybrid Automata
Chen, Yangzhou; Guo, Yuqi; Wang, Ying
2017-01-01
In this paper, in order to describe complex network systems, we firstly propose a general modeling framework by combining a dynamic graph with hybrid automata and thus name it Dynamic Graph Hybrid Automata (DGHA). Then we apply this framework to model traffic flow over an urban freeway network by embedding the Cell Transmission Model (CTM) into the DGHA. With a modeling procedure, we adopt a dual digraph of road network structure to describe the road topology, use linear hybrid automata to describe multi-modes of dynamic densities in road segments and transform the nonlinear expressions of the transmitted traffic flow between two road segments into piecewise linear functions in terms of multi-mode switchings. This modeling procedure is modularized and rule-based, and thus is easily-extensible with the help of a combination algorithm for the dynamics of traffic flow. It can describe the dynamics of traffic flow over an urban freeway network with arbitrary topology structures and sizes. Next we analyze mode types and number in the model of the whole freeway network, and deduce a Piecewise Affine Linear System (PWALS) model. Furthermore, based on the PWALS model, a multi-mode switched state observer is designed to estimate the traffic densities of the freeway network, where a set of observer gain matrices are computed by using the Lyapunov function approach. As an example, we utilize the PWALS model and the corresponding switched state observer to traffic flow over Beijing third ring road. In order to clearly interpret the principle of the proposed method and avoid computational complexity, we adopt a simplified version of Beijing third ring road. Practical application for a large-scale road network will be implemented by decentralized modeling approach and distributed observer designing in the future research. PMID:28353664
Modeling and Density Estimation of an Urban Freeway Network Based on Dynamic Graph Hybrid Automata.
Chen, Yangzhou; Guo, Yuqi; Wang, Ying
2017-03-29
In this paper, in order to describe complex network systems, we firstly propose a general modeling framework by combining a dynamic graph with hybrid automata and thus name it Dynamic Graph Hybrid Automata (DGHA). Then we apply this framework to model traffic flow over an urban freeway network by embedding the Cell Transmission Model (CTM) into the DGHA. With a modeling procedure, we adopt a dual digraph of road network structure to describe the road topology, use linear hybrid automata to describe multi-modes of dynamic densities in road segments and transform the nonlinear expressions of the transmitted traffic flow between two road segments into piecewise linear functions in terms of multi-mode switchings. This modeling procedure is modularized and rule-based, and thus is easily-extensible with the help of a combination algorithm for the dynamics of traffic flow. It can describe the dynamics of traffic flow over an urban freeway network with arbitrary topology structures and sizes. Next we analyze mode types and number in the model of the whole freeway network, and deduce a Piecewise Affine Linear System (PWALS) model. Furthermore, based on the PWALS model, a multi-mode switched state observer is designed to estimate the traffic densities of the freeway network, where a set of observer gain matrices are computed by using the Lyapunov function approach. As an example, we utilize the PWALS model and the corresponding switched state observer to traffic flow over Beijing third ring road. In order to clearly interpret the principle of the proposed method and avoid computational complexity, we adopt a simplified version of Beijing third ring road. Practical application for a large-scale road network will be implemented by decentralized modeling approach and distributed observer designing in the future research.
The Near-road EXposures to Urban air pollutant Study (NEXUS) investigated whether children with asthma living in close proximity to major roadways in Detroit, MI, (particularly near roadways with high diesel traffic) have greater health impacts associated with exposure to air pol...
ERIC Educational Resources Information Center
O'Shaughnessy, Molly
2016-01-01
"Children have the potential to create a world we cannot imagine. This is our hope." In choosing Montessori, O'Shaughnessy says that we are choosing the road less traveled. We are choosing education as an aid to life. We are choosing an approach that respects the innate and unique potential of each child and that calls upon us to serve…
11. Photographic copy of lines drawing of original construction (24 ...
11. Photographic copy of lines drawing of original construction (24 January 1911, in possession of St. Louis County Bridge Engineer, Virginia, Minnesota). Profile of main and approach spans; plan and sectional view of concrete river pier - Brosseau Road Bridge, County Road 694 spanning Cloquet at River, Burnett, St. Louis County, MN
Driver behaviour profiles for road safety analysis.
Ellison, Adrian B; Greaves, Stephen P; Bliemer, Michiel C J
2015-03-01
Driver behaviour is a contributing factor in over 90 percent of road crashes. As a consequence, there is significant benefit in identifying drivers who engage in unsafe driving practices. Driver behaviour profiles (DBPs) are introduced here as an approach for evaluating driver behaviour as a function of the risk of a casualty crash. They employ data collected using global positioning system (GPS) devices, supplemented with spatiotemporal information. These profiles are comprised of common risk scores that can be used to compare drivers between each other and across time and space. The paper details the development of these DBPs and demonstrates their use as an input into modelling the factors that influence driver behaviour. The results show that even having controlled for the influence of the road environment, these factors remain the strongest predictors of driver behaviour suggesting different spatiotemporal environments elicit a variety of psychological responses in drivers. The approach and outcomes will be of interest to insurance companies in enhancing the risk-profiling of drivers with on-road driving and government through assessing the impacts of behaviour-change interventions. Copyright © 2015 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Corrigan, A.; Silins, U.; Stone, M.
2016-12-01
Best management practices (BMPs) and associated erosion control measures for mitigating sediment impacts from forestry roads and road-stream crossings are well documented. While rapid road decommissioning after forestry operations may serve to limit broader impacts on sediment production in high value headwater streams, few studies have evaluated the combined effects of accelerated harvest operations and rapid retirement of logging roads and road-stream crossings on stream sediment. The objectives of this study were to evaluate the initial impacts of these strategies on fine sediment loading and fate during a short duration harvesting operation in 3 headwater sub-catchments in the southwestern Rocky Mountains of Alberta, Canada. A multi-pronged sampling approach (ISCOs, event focused grab sampling, continuous wash load sampling, and stream bed sediment intrusion measurements) was used to measure sediment loading and deposition in streambeds upstream and downstream of road-stream bridge crossings during harvest operations (2015) and after road and bridge crossing retirement (2016). Sediment production from forestry roads was generally much lower than has been reported from other studies in similar settings. Average total suspended solids (TSS) downstream of the bridge crossings were actually lower (-3.28 g/L; -0.704 g/L) than upstream of two bridge crossings while in-stream sediment sources contributed to elevated sediment downstream of a third road-stream crossing. Minimal in stream sediment impacts from forest harvest and road-stream crossings was likely a reflection of combined factors including a) employment of erosion control BMPs to roads and bridge crossings, b) rapid decommissioning of roads and crossings to limit exposure of linear land disturbance features, and c) drier El Niño climatic conditions during the study.
How Effective Is Road Mitigation at Reducing Road-Kill? A Meta-Analysis.
Rytwinski, Trina; Soanes, Kylie; Jaeger, Jochen A G; Fahrig, Lenore; Findlay, C Scott; Houlahan, Jeff; van der Ree, Rodney; van der Grift, Edgar A
2016-01-01
Road traffic kills hundreds of millions of animals every year, posing a critical threat to the populations of many species. To address this problem there are more than forty types of road mitigation measures available that aim to reduce wildlife mortality on roads (road-kill). For road planners, deciding on what mitigation method to use has been problematic because there is little good information about the relative effectiveness of these measures in reducing road-kill, and the costs of these measures vary greatly. We conducted a meta-analysis using data from 50 studies that quantified the relationship between road-kill and a mitigation measure designed to reduce road-kill. Overall, mitigation measures reduce road-kill by 40% compared to controls. Fences, with or without crossing structures, reduce road-kill by 54%. We found no detectable effect on road-kill of crossing structures without fencing. We found that comparatively expensive mitigation measures reduce large mammal road-kill much more than inexpensive measures. For example, the combination of fencing and crossing structures led to an 83% reduction in road-kill of large mammals, compared to a 57% reduction for animal detection systems, and only a 1% for wildlife reflectors. We suggest that inexpensive measures such as reflectors should not be used until and unless their effectiveness is tested using a high-quality experimental approach. Our meta-analysis also highlights the fact that there are insufficient data to answer many of the most pressing questions that road planners ask about the effectiveness of road mitigation measures, such as whether other less common mitigation measures (e.g., measures to reduce traffic volume and/or speed) reduce road mortality, or to what extent the attributes of crossing structures and fences influence their effectiveness. To improve evaluations of mitigation effectiveness, studies should incorporate data collection before the mitigation is applied, and we recommend a minimum study duration of four years for Before-After, and a minimum of either four years or four sites for Before-After-Control-Impact designs.
Automated road network extraction from high spatial resolution multi-spectral imagery
NASA Astrophysics Data System (ADS)
Zhang, Qiaoping
For the last three decades, the Geomatics Engineering and Computer Science communities have considered automated road network extraction from remotely-sensed imagery to be a challenging and important research topic. The main objective of this research is to investigate the theory and methodology of automated feature extraction for image-based road database creation, refinement or updating, and to develop a series of algorithms for road network extraction from high resolution multi-spectral imagery. The proposed framework for road network extraction from multi-spectral imagery begins with an image segmentation using the k-means algorithm. This step mainly concerns the exploitation of the spectral information for feature extraction. The road cluster is automatically identified using a fuzzy classifier based on a set of predefined road surface membership functions. These membership functions are established based on the general spectral signature of road pavement materials and the corresponding normalized digital numbers on each multi-spectral band. Shape descriptors of the Angular Texture Signature are defined and used to reduce the misclassifications between roads and other spectrally similar objects (e.g., crop fields, parking lots, and buildings). An iterative and localized Radon transform is developed for the extraction of road centerlines from the classified images. The purpose of the transform is to accurately and completely detect the road centerlines. It is able to find short, long, and even curvilinear lines. The input image is partitioned into a set of subset images called road component images. An iterative Radon transform is locally applied to each road component image. At each iteration, road centerline segments are detected based on an accurate estimation of the line parameters and line widths. Three localization approaches are implemented and compared using qualitative and quantitative methods. Finally, the road centerline segments are grouped into a road network. The extracted road network is evaluated against a reference dataset using a line segment matching algorithm. The entire process is unsupervised and fully automated. Based on extensive experimentation on a variety of remotely-sensed multi-spectral images, the proposed methodology achieves a moderate success in automating road network extraction from high spatial resolution multi-spectral imagery.
How Effective Is Road Mitigation at Reducing Road-Kill? A Meta-Analysis
Rytwinski, Trina; Soanes, Kylie; Jaeger, Jochen A. G.; Fahrig, Lenore; Findlay, C. Scott; Houlahan, Jeff; van der Ree, Rodney; van der Grift, Edgar A
2016-01-01
Road traffic kills hundreds of millions of animals every year, posing a critical threat to the populations of many species. To address this problem there are more than forty types of road mitigation measures available that aim to reduce wildlife mortality on roads (road-kill). For road planners, deciding on what mitigation method to use has been problematic because there is little good information about the relative effectiveness of these measures in reducing road-kill, and the costs of these measures vary greatly. We conducted a meta-analysis using data from 50 studies that quantified the relationship between road-kill and a mitigation measure designed to reduce road-kill. Overall, mitigation measures reduce road-kill by 40% compared to controls. Fences, with or without crossing structures, reduce road-kill by 54%. We found no detectable effect on road-kill of crossing structures without fencing. We found that comparatively expensive mitigation measures reduce large mammal road-kill much more than inexpensive measures. For example, the combination of fencing and crossing structures led to an 83% reduction in road-kill of large mammals, compared to a 57% reduction for animal detection systems, and only a 1% for wildlife reflectors. We suggest that inexpensive measures such as reflectors should not be used until and unless their effectiveness is tested using a high-quality experimental approach. Our meta-analysis also highlights the fact that there are insufficient data to answer many of the most pressing questions that road planners ask about the effectiveness of road mitigation measures, such as whether other less common mitigation measures (e.g., measures to reduce traffic volume and/or speed) reduce road mortality, or to what extent the attributes of crossing structures and fences influence their effectiveness. To improve evaluations of mitigation effectiveness, studies should incorporate data collection before the mitigation is applied, and we recommend a minimum study duration of four years for Before-After, and a minimum of either four years or four sites for Before-After-Control-Impact designs. PMID:27870889
A sonification algorithm for developing the off-roads models for driving simulators
NASA Astrophysics Data System (ADS)
Chiroiu, Veturia; Brişan, Cornel; Dumitriu, Dan; Munteanu, Ligia
2018-01-01
In this paper, a sonification algorithm for developing the off-road models for driving simulators, is proposed. The aim of this algorithm is to overcome difficulties of heuristics identification which are best suited to a particular off-road profile built by measurements. The sonification algorithm is based on the stochastic polynomial chaos analysis suitable in solving equations with random input data. The fluctuations are generated by incomplete measurements leading to inhomogeneities of the cross-sectional curves of off-roads before and after deformation, the unstable contact between the tire and the road and the unreal distribution of contact and friction forces in the unknown contact domains. The approach is exercised on two particular problems and results compare favorably to existing analytical and numerical solutions. The sonification technique represents a useful multiscale analysis able to build a low-cost virtual reality environment with increased degrees of realism for driving simulators and higher user flexibility.
Strategies for prevention of road traffic injuries (RTIs) in Pakistan: situational analysis.
Khan, Adeel Ahmed; Fatmi, Zafar
2014-05-01
Road traffic injuries (RTIs) are one of the leading causes of death among productive age group. Using systems approach framework (SAF), current preventive strategies for RTI control were reviewed in Pakistan. A review of the literature was done using four international search engines. Only ten studies on preventive strategies for RTI stemming from Pakistan were found. The first Road Traffic Injuries Research Network (RTIRN) surveillance system for road traffic injuries was established in urban city (Karachi) in Pakistan has shown promise for injury control and should be scaled up to other cities. Enforcement of traffic laws on seat-belt and helmet wearing is poor. National Highway and Motorway Police Ordinance (2000) was one of the few legislative measure so far taken in Pakistan. Using SAF, efforts are required to implement interventions targeting human, vehicle design and also making environment safer for road users.
NASA Astrophysics Data System (ADS)
Costanzo, Antonio; Montuori, Antonio; Silva, Juan Pablo; Silvestri, Malvina; Musacchio, Massimo; Buongiorno, Maria Fabrizia; Stramondo, Salvatore
2016-08-01
In this work, a web-GIS procedure to map the risk of road blockage in urban environments through the combined use of space-borne and airborne remote sensing sensors is presented. The methodology concerns (1) the provision of a geo-database through the integration of space-borne multispectral images and airborne LiDAR data products; (2) the modeling of building vulnerability, based on the corresponding 3D geometry and construction time information; (3) the GIS-based mapping of road closure due to seismic- related building collapses based on the building characteristic height and the width of the road. Experimental results, gathered for the Cosenza urban area, allow demonstrating the benefits of both the proposed approach and the GIS-based integration of multi-platforms remote sensing sensors and techniques for seismic road assessment purposes.
Road Nail: Experimental Solar Powered Intelligent Road Marking System
NASA Astrophysics Data System (ADS)
Samardžija, Dragan; Teslić, Nikola; Todorović, Branislav M.; Kovač, Erne; Isailović, Đorđe; Miladinović, Bojan
2012-03-01
Driving in low visibility conditions (night time, fog or heavy precipitation) is particularly challenging task with an increased probability of traffic accidents and possible injuries. Road Nail is a solar powered intelligent road marking system of wirelessly networked signaling devices that improve driver safety in low visibility conditions along hazardous roadways. Nails or signaling devices are autonomous nodes with capability to accumulate energy, exchange wireless messages, detect approaching vehicles and emit signalization light. We have built an experimental test-bed that consists of 20 nodes and a cellular gateway. Implementation details of the above system, including extensive measurements and performance evaluations in realistic field deployments are presented. A novel distributed network topology discovery scheme is proposed which integrates both sensor and wireless communication aspects, where nodes act autonomously. Finally, integration of the Road Nail system with the cellular network and the Internet is described.
Naturalistic validation of an on-road driving test of older drivers.
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.
Do well-connected landscapes promote road-related mortality?
Grilo, C.; Ascensao, F.; Santos-Reis, M.; Bissonette, J.A.
2011-01-01
Cost surface (CS) models have emerged as a useful tool to examine the interactions between landscapes patterns and wildlife at large-scale extents. This approach is particularly relevant to guide conservation planning for species that show vulnerability to road networks in human-dominated landscapes. In this study, we measured the functional connectivity of the landscape in southern Portugal and examined how it may be related to stone marten road mortality risk. We addressed three questions: (1) How different levels of landscape connectivity influence stone marten occurrence in montado patches? (2) Is there any relation between montado patches connectivity and stone marten road mortality risk? (3) If so, which road-related features might be responsible for the species' high road mortality? We developed a series of connectivity models using CS scenarios with different resistance values given to each vegetation cover type to reflect different resistance to species movement. Our models showed that the likelihood of occurrence of stone marten decreased with distance to source areas, meaning continuous montado. Open areas and riparian areas within open area matrices entailed increased costs. We found higher stone marten mortality on roads in well-connected areas. Road sinuosity was an important factor influencing the mortality in those areas. This result challenges the way that connectivity and its relation to mortality has been generally regarded. Clearly, landscape connectivity and road-related mortality are not independent. ?? 2010 Springer-Verlag.
Analysis of road development and associated agricultural land use change.
Alphan, Hakan
2017-12-05
Development of road network is one of the strongest drivers of habitat fragmentation. It interferes with ecological processes that are based on material and energy flows between landscape patches. Therefore, changes in temporal patterns of roads may be regarded as important landscape-level environmental indicators. The aim of this study is to analyze road development and associated agricultural land use change near the town of Erdemli located in the eastern Mediterranean coast of Turkey. The study area has witnessed an unprecedented development of agriculture since the 2000s. This process has resulted with the expansion of the road network. Associations between agricultural expansion and road development were investigated. High-resolution satellite images of 2004 and 2015 were used to analyze spatial and temporal dimensions of change. Satellite images were classified using a binary approach, in which land areas were labeled as either "agriculture" or "non-agriculture." Road networks were digitized manually. The study area was divided into 23 sublandscapes using a regular grid with 1-km cell spacing. Percentage of landscape (PL) for agriculture and road density (RD) metrics were calculated for the earlier (2004) and later (2015) years. Metric calculations were performed separately for each of the 23 sublandscapes in order to understand spatial diversity of agriculture and road density. Study results showed that both RD and PL exhibited similar increasing trends between 2004 and 2015.
Fear patterns: a new approach to designing road safety advertisements.
Algie, Jennifer; Rossiter, John R
2010-01-01
This research studies fear patterns within fear appeal anti-speeding television commercials. A pattern of fear is the sequence of fear arousal and fear reduction, if any, that is felt by the viewing audience when exposed to a fear appeal advertisement. Many road safety advertisers use fear appeals, such as "shock" advertising, that result in fear arousal, leaving the viewer feeling extremely tense. The moment-to-moment reactions of young drivers to 12 road safety commercials are gauged using a dynamic, temporal measure of fear. The fear patterns generated from each ad are analyzed and a new perspective on creating fear appeal road safety advertisements, with an emphasis on fear-relief, fear-partial relief, and fear-only patterns, is discussed.
NASA Astrophysics Data System (ADS)
Hamdi, Hadiwardoyo, Sigit P.; Correia, A. Gomes; Pereira, Paulo
2017-06-01
A road network requires timely maintenance to keep the road surface in good condition onward better services to improve accessibility and mobility. Strategies and maintenance techniques must be chosen in order to maximize road service level through cost-effective interventions. This approach requires an updated database, which the road network in Indonesia is supported by a manual and visual survey, also using NAASRA profiler. Furthermore, in this paper, the deterministic model of deterioration was used. This optimization model uses life cycle cost analysis (LCCA), applied in an integrated manner, using IRI indicator, and allows determining the priority of treatment, type of treatment and its relation to the cost. The purpose of this paper was focussed on the aspects of road maintenance management, i.e., maintenance optimization models for different levels of traffic and various initial of road distress conditions on the national road network in Indonesia. The implementation of Integrated Road Management System (IRMS) can provide a solution to the problem of cost constraints in the maintenance of the national road network. The results from this study found that as the lowest as agency cost, it will affect the increasing of user cost. With the achievement of the target plan scenario Pl000 with initial value IRI 2, it was found that the routine management throughout the year and in early reconstruction and periodic maintenance with a 30 mm thick overlay, will simultaneously provide a higher net benefit value and has the lowest total cost of transportation.
Vision-Based Steering Control, Speed Assistance and Localization for Inner-City Vehicles
Olivares-Mendez, Miguel Angel; Sanchez-Lopez, Jose Luis; Jimenez, Felipe; Campoy, Pascual; Sajadi-Alamdari, Seyed Amin; Voos, Holger
2016-01-01
Autonomous route following with road vehicles has gained popularity in the last few decades. In order to provide highly automated driver assistance systems, different types and combinations of sensors have been presented in the literature. However, most of these approaches apply quite sophisticated and expensive sensors, and hence, the development of a cost-efficient solution still remains a challenging problem. This work proposes the use of a single monocular camera sensor for an automatic steering control, speed assistance for the driver and localization of the vehicle on a road. Herein, we assume that the vehicle is mainly traveling along a predefined path, such as in public transport. A computer vision approach is presented to detect a line painted on the road, which defines the path to follow. Visual markers with a special design painted on the road provide information to localize the vehicle and to assist in its speed control. Furthermore, a vision-based control system, which keeps the vehicle on the predefined path under inner-city speed constraints, is also presented. Real driving tests with a commercial car on a closed circuit finally prove the applicability of the derived approach. In these tests, the car reached a maximum speed of 48 km/h and successfully traveled a distance of 7 km without the intervention of a human driver and any interruption. PMID:26978365
Vision-Based Steering Control, Speed Assistance and Localization for Inner-City Vehicles.
Olivares-Mendez, Miguel Angel; Sanchez-Lopez, Jose Luis; Jimenez, Felipe; Campoy, Pascual; Sajadi-Alamdari, Seyed Amin; Voos, Holger
2016-03-11
Autonomous route following with road vehicles has gained popularity in the last few decades. In order to provide highly automated driver assistance systems, different types and combinations of sensors have been presented in the literature. However, most of these approaches apply quite sophisticated and expensive sensors, and hence, the development of a cost-efficient solution still remains a challenging problem. This work proposes the use of a single monocular camera sensor for an automatic steering control, speed assistance for the driver and localization of the vehicle on a road. Herein, we assume that the vehicle is mainly traveling along a predefined path, such as in public transport. A computer vision approach is presented to detect a line painted on the road, which defines the path to follow. Visual markers with a special design painted on the road provide information to localize the vehicle and to assist in its speed control. Furthermore, a vision-based control system, which keeps the vehicle on the predefined path under inner-city speed constraints, is also presented. Real driving tests with a commercial car on a closed circuit finally prove the applicability of the derived approach. In these tests, the car reached a maximum speed of 48 km/h and successfully traveled a distance of 7 km without the intervention of a human driver and any interruption.
Economic, Socio-Political and Environmental Risks of Road Development in the Tropics.
Alamgir, Mohammed; Campbell, Mason J; Sloan, Sean; Goosem, Miriam; Clements, Gopalasamy Reuben; Mahmoud, Mahmoud I; Laurance, William F
2017-10-23
It is projected that 25 million km of new paved roads will be developed globally by 2050 - enough to encircle the planet more than 600 times. Roughly 90% of new roads will be built in developing nations, frequently in tropical and subtropical regions with high biodiversity and environmental values. Many developing nations are borrowing from international lenders or negotiating access to their natural resources in order to expand their transportation infrastructure. Given the unprecedented pace and extent of these initiatives, it is vital to thoroughly assess the potential consequences of large-scale road and highway projects. In appropriate contexts and locales, new roads can promote sizeable economic and social benefits. If poorly planned or implemented, however, new roads can provoke serious cost overruns, corruption and environmental impacts, while generating sparse economic benefits and intense social and political conflict. Using examples from developing nations, we identify risks that can hinder road projects in wet and dry tropical environments. Such risks, we assert, are often inadequately considered by project proponents, evaluators and the general public, creating a systematic tendency to overestimate project benefits while understating project risks. A more precautionary approach is needed to reduce risks while maximizing benefits of new road projects in the tropics. Copyright © 2017 Elsevier Ltd. All rights reserved.
Jacoby, Sara F; Winston, Flaura K; Richmond, Therese S
2017-12-01
In rapidly developing economies, like urban India, where road traffic injury rates are among the world's highest, the corporate workplace offers a non-traditional venue for road safety interventions. In partnership with a major multinational corporation (MNC) with a large Indian workforce, this study aimed to elicit local employee perspectives on road safety to inform a global corporate health platform. The safety attitudes and behaviours of 75 employees were collected through self-report survey and focus groups in the MNC offices in Bangalore and Pune. Analysis of these data uncovered incongruity between employee knowledge of safety strategies and their enacted safety behaviours and identified local preference for interventions and policy-level actions. The methods modelled by this study offer a straightforward approach for eliciting employee perspective for local road safety interventions that fit within a global strategy to improve employee health. Study findings suggest that MNCs can employ a range of strategies to improve the road traffic safety of their employees in settings like urban India including: implementing corporate traffic safety policy, making local infrastructure changes to improve road and traffic conditions, advocating for road safety with government partners and providing employees with education and access to safety equipment and safe transportation options.
Cluster categorization of urban roads to optimize their noise monitoring.
Zambon, G; Benocci, R; Brambilla, G
2016-01-01
Road traffic in urban areas is recognized to be associated with urban mobility and public health, and it is often the main source of noise pollution. Lately, noise maps have been considered a powerful tool to estimate the population exposure to environmental noise, but they need to be validated by measured noise data. The project Dynamic Acoustic Mapping (DYNAMAP), co-funded in the framework of the LIFE 2013 program, is aimed to develop a statistically based method to optimize the choice and the number of monitoring sites and to automate the noise mapping update using the data retrieved from a low-cost monitoring network. Indeed, the first objective should improve the spatial sampling based on the legislative road classification, as this classification is mainly based on the geometrical characteristics of the road, rather than its noise emission. The present paper describes the statistical approach of the methodology under development and the results of its preliminary application to a limited sample of roads in the city of Milan. The resulting categorization of roads, based on clustering the 24-h hourly L Aeqh, looks promising to optimize the spatial sampling of noise monitoring toward a description of the noise pollution due to complex urban road networks more efficient than that based on the legislative road classification.
Roads, interrupted dispersal, and genetic diversity in timber rattlesnakes.
Clark, Rulon W; Brown, William S; Stechert, Randy; Zamudio, Kelly R
2010-08-01
Anthropogenic habitat modification often creates barriers to animal movement, transforming formerly contiguous habitat into a patchwork of habitat islands with low connectivity. Roadways are a feature of most landscapes that can act as barriers or filters to migration among local populations. Even small and recently constructed roads can have a significant impact on population genetic structure of some species, but not others. We developed a research approach that combines fine-scale molecular genetics with behavioral and ecological data to understand the impacts of roads on population structure and connectivity. We used microsatellite markers to characterize genetic variation within and among populations of timber rattlesnakes (Crotalus horridus) occupying communal hibernacula (dens) in regions bisected by roadways. We examined the impact of roads on seasonal migration, genetic diversity, and gene flow among populations. Snakes in hibernacula isolated by roads had significantly lower genetic diversity and higher genetic differentiation than snakes in hibernacula in contiguous habitat. Genetic-assignment analyses revealed that interruption to seasonal migration was the mechanism underlying these patterns. Our results underscore the sizeable impact of roads on this species, despite their relatively recent construction at our study sites (7 to 10 generations of rattlesnakes), the utility of population genetics for studies of road ecology, and the need for mitigating effects of roads.
39. MISSISSIPPI, LOWNDES CO. COLUMBUS OLD ROAD BRIDGE End of ...
39. MISSISSIPPI, LOWNDES CO. COLUMBUS OLD ROAD BRIDGE End of Main St., Columbus Both spans of 1878 bridge during flood. Taken from top of the E approach. Credit: Shenks Photography, Columbus, Ms, owner. O. Pruitt, photographer, Apr. 8 1882. Sarcone Photography, Columbus, Ms. Sep 1978. - Bridges of the Upper Tombigbee River Valley, Columbus, Lowndes County, MS
ERIC Educational Resources Information Center
Kairuddin; Darmawijoyo
2011-01-01
This paper highlights the Indonesian's road transportation contexts, namely, angkot, that used in learning and teaching of addition and subtraction in first grade and second grade MIN-2 Palembang. PMRI approach that adopt from RME [Realistic Mathematics Education] was used in this design research. From teaching experiment was founded that the…
Straight A's: Public Education Policy and Progress. Volume 12, Number 9
ERIC Educational Resources Information Center
Amos, Jason, Ed.
2012-01-01
"Straight A's: Public Education Policy and Progress" is a biweekly newsletter that focuses on education news and events both in Washington, DC and around the country. The following articles are included in this issue: (1) You Take the High Road and I'll Take the Low Road: As Appropriations Process Begins, Different Spending Approaches Likely to…
You Can Get There from Here: The Road to Downsizing in Higher Education.
ERIC Educational Resources Information Center
Butterfield, Barbara S.; Wolfe, Susan
This book approaches college and university budget reduction mandates as an opportunity to reexamine and recast outdated, inefficient processes and to increase administrative effectiveness and efficiency in supporting the academic missions of teaching and research. The book uses a road-map metaphor to tell the downsizing story and to advance the…
New Training Approaches for Drivers--A Practical Experience
ERIC Educational Resources Information Center
Catenazzi, Nadia; Sommaruga, Lorenzo; De Angelis, Kylene; Gabbianelli, Giulio
2018-01-01
In the context of the road transport there is the need to provide new training opportunities for million of truck and bus drivers who are often on the road. The C95-Challenge EU Erasmus+ project aims to meet this need by introducing new training methodologies and solutions that support compulsory periodic courses. The main project result is the…
Hatamabadi, Hamidreza; Vafaee, Reza; Hadadi, Mashyaneh; Abdalvand, Ali; Esnaashari, Hamidreza; Soori, Hamid
2012-01-01
Crash injuries in traffic accidents are affected by a variety of factors. In this study we analyzed road user type information based on different contributing factors. Data from all of the road traffic victims on a road extending from the east of the city of Tehran to Mazandaran province were included prospectively over a one-year period (May 2008 to May 2009). Data collected included the crash time, patient's age and sex, road user category, helmet or seat belt use, anatomical site of injury, Injury Severity Score (ISS), and mortality. Prevalence and cross-tabulations were included in the analysis. There were 433 patients, of whom 345 were hospitalized and 33 died either before or after arriving at the hospital. Sixty-nine percent of injured patients were vehicle occupants. Mean and median of ISS were higher for pedestrians, who accounted for 49 percent of the deaths. Head injury was the most common injury and injury to upper and lower extremities was the most common cause of admission. A significant difference in lower extremity injuries between vehicle occupants and nonoccupants was found. Sex and age group did not have a significant effect on mortality. Mortality was significantly higher in pedestrians (P < .001) when data were analyzed based on road user type. Because pedestrians are the most vulnerable road users, stricter legislation and law enforcement should be used to protect them. Greater protection can also be reached by holding effective public awareness campaigns on how to use different roads safely. On the other hand, because rear seat passengers are at the same risk for road traffic injuries as front seat passengers, employment of newer laws and preventive measures targeting this group of occupants can prevent many road traffic injuries (RTIs).
Adaptive road crack detection system by pavement classification.
Gavilán, Miguel; Balcones, David; Marcos, Oscar; Llorca, David F; Sotelo, Miguel A; Parra, Ignacio; Ocaña, Manuel; Aliseda, Pedro; Yarza, Pedro; Amírola, Alejandro
2011-01-01
This paper presents a road distress detection system involving the phases needed to properly deal with fully automatic road distress assessment. A vehicle equipped with line scan cameras, laser illumination and acquisition HW-SW is used to storage the digital images that will be further processed to identify road cracks. Pre-processing is firstly carried out to both smooth the texture and enhance the linear features. Non-crack features detection is then applied to mask areas of the images with joints, sealed cracks and white painting, that usually generate false positive cracking. A seed-based approach is proposed to deal with road crack detection, combining Multiple Directional Non-Minimum Suppression (MDNMS) with a symmetry check. Seeds are linked by computing the paths with the lowest cost that meet the symmetry restrictions. The whole detection process involves the use of several parameters. A correct setting becomes essential to get optimal results without manual intervention. A fully automatic approach by means of a linear SVM-based classifier ensemble able to distinguish between up to 10 different types of pavement that appear in the Spanish roads is proposed. The optimal feature vector includes different texture-based features. The parameters are then tuned depending on the output provided by the classifier. Regarding non-crack features detection, results show that the introduction of such module reduces the impact of false positives due to non-crack features up to a factor of 2. In addition, the observed performance of the crack detection system is significantly boosted by adapting the parameters to the type of pavement.
Adaptive Road Crack Detection System by Pavement Classification
Gavilán, Miguel; Balcones, David; Marcos, Oscar; Llorca, David F.; Sotelo, Miguel A.; Parra, Ignacio; Ocaña, Manuel; Aliseda, Pedro; Yarza, Pedro; Amírola, Alejandro
2011-01-01
This paper presents a road distress detection system involving the phases needed to properly deal with fully automatic road distress assessment. A vehicle equipped with line scan cameras, laser illumination and acquisition HW-SW is used to storage the digital images that will be further processed to identify road cracks. Pre-processing is firstly carried out to both smooth the texture and enhance the linear features. Non-crack features detection is then applied to mask areas of the images with joints, sealed cracks and white painting, that usually generate false positive cracking. A seed-based approach is proposed to deal with road crack detection, combining Multiple Directional Non-Minimum Suppression (MDNMS) with a symmetry check. Seeds are linked by computing the paths with the lowest cost that meet the symmetry restrictions. The whole detection process involves the use of several parameters. A correct setting becomes essential to get optimal results without manual intervention. A fully automatic approach by means of a linear SVM-based classifier ensemble able to distinguish between up to 10 different types of pavement that appear in the Spanish roads is proposed. The optimal feature vector includes different texture-based features. The parameters are then tuned depending on the output provided by the classifier. Regarding non-crack features detection, results show that the introduction of such module reduces the impact of false positives due to non-crack features up to a factor of 2. In addition, the observed performance of the crack detection system is significantly boosted by adapting the parameters to the type of pavement. PMID:22163717
Cornelissen, M; Salmon, P M; Stanton, N A; McClure, R
2015-01-01
While a safe systems approach has long been acknowledged as the underlying philosophy of contemporary road safety strategies, systemic applications are sparse. This article argues that systems-based methods from the discipline of Ergonomics have a key role to play in road transport design and evaluation. To demonstrate, the Cognitive Work Analysis framework was used to evaluate two road designs - a traditional Melbourne intersection and a cut-through design for future intersections based on road safety safe systems principles. The results demonstrate that, although the cut-through intersection appears different in layout from the traditional intersection, system constraints are not markedly different. Furthermore, the analyses demonstrated that redistribution of constraints in the cut-through intersection resulted in emergent behaviour, which was not anticipated and could prove problematic. Further, based on the lack of understanding of emergent behaviour, similar design induced problems are apparent across both intersections. Specifically, incompatibilities between infrastructure, vehicles and different road users were not dealt with by the proposed design changes. The importance of applying systems methods in the design and evaluation of road transport systems is discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Hazelhoff, Lykele; Creusen, Ivo M.; Woudsma, Thomas; de With, Peter H. N.
2015-11-01
Combined databases of road markings and traffic signs provide a complete and full description of the present traffic legislation and instructions. Such databases contribute to efficient signage maintenance, improve navigation, and benefit autonomous driving vehicles. A system is presented for the automated creation of such combined databases, which additionally investigates the benefit of this combination for automated contextual placement analysis. This analysis involves verification of the co-occurrence of traffic signs and road markings to retrieve a list of potentially incorrectly signaled (and thus potentially unsafe) road situations. This co-occurrence verification is specifically explored for both pedestrian crossings and yield situations. Evaluations on 420 km of road have shown that individual detection of traffic signs and road markings denoting these road situations can be performed with accuracies of 98% and 85%, respectively. Combining both approaches shows that over 95% of the pedestrian crossings and give-way situations can be identified. An exploration toward additional co-occurrence analysis of signs and markings shows that inconsistently signaled situations can successfully be extracted, such that specific safety actions can be directed toward cases lacking signs or markings, while most consistently signaled situations can be omitted from this analysis.
Young, Kristie L; Salmon, Paul M
2015-01-01
Distracted driving is acknowledged universally as a large and growing road safety problem. Compounding the problem is that distracted driving is a complex, multifaceted issue influenced by a multitude of factors, organisations and individuals. As such, management of the problem is not straightforward. Numerous countermeasures have been developed and implemented across the globe. The vast majority of these measures have derived from the traditional reductionist, driver-centric approach to distraction and have failed to fully reflect the complex mix of actors and components that give rise to drivers becoming distracted. An alternative approach that is gaining momentum in road safety is the systems approach, which considers all components of the system and their interactions as an integrated whole. In this paper, we review the current knowledge base on driver distraction and argue that the systems approach is not currently being realised in practice. Adopting a more holistic, systems approach to distracted driving will not only improve existing knowledge and interventions from the traditional approach, but will enhance our understanding and management of distraction by considering the complex relationships and interactions of the multiple actors and the myriad sources, enablers and interventions that make up the distracted driving system. It is only by recognising and understanding how all of the system components work together to enable distraction to occur, that we can start to work on solutions to help mitigate the occurrence and consequences of distracted driving. Copyright © 2014 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
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.
Loggers and Forest Fragmentation: Behavioral Models of Road Building in the Amazon Basin
NASA Technical Reports Server (NTRS)
Arima, Eugenio Y.; Walker, Robert T.; Perz, Stephen G.; Caldas, Marcellus
2005-01-01
Although a large literature now exists on the drivers of tropical deforestation, less is known about its spatial manifestation. This is a critical shortcoming in our knowledge base since the spatial pattern of land-cover change and forest fragmentation, in particular, strongly affect biodiversity. The purpose of this article is to consider emergent patterns of road networks, the initial proximate cause of fragmentation in tropical forest frontiers. Specifically, we address the road-building processes of loggers who are very active in the Amazon landscape. To this end, we develop an explanation of road expansions, using a positive approach combining a theoretical model of economic behavior with geographic information systems (GIs) software in order to mimic the spatial decisions of road builders. We simulate two types of road extensions commonly found in the Amazon basin in a region: showing the fishbone pattern of fragmentation. Although our simulation results are only partially successful, they call attention to the role of multiple agents in the landscape, the importance of legal and institutional constraints on economic behavior, and the power of GIs as a research tool.
Recognition Stage for a Speed Supervisor Based on Road Sign Detection
Carrasco, Juan-Pablo; de la Escalera, Arturo; Armingol, José María
2012-01-01
Traffic accidents are still one of the main health problems in the World. A number of measures have been applied in order to reduce the number of injuries and fatalities in roads, i.e., implementation of Advanced Driver Assistance Systems (ADAS) based on image processing. In this paper, a real time speed supervisor based on road sign recognition that can work both in urban and non-urban environments is presented. The system is able to recognize 135 road signs, belonging to the danger, yield, prohibition obligation and indication types, and sends warning messages to the driver upon the combination of two pieces of information: the current speed of the car and the road sign symbol. The core of this paper is the comparison between the two main methods which have been traditionally used for detection and recognition of road signs: template matching (TM) and neural networks (NN). The advantages and disadvantages of the two approaches will be shown and commented. Additionally we will show how the use of well-known algorithms to avoid illumination issues reduces the amount of images needed to train a neural network.
Off-road motorbike performance analysis using a rear semi-active suspension
NASA Astrophysics Data System (ADS)
Lozoya-Santos, Jorge de J.; Cervantes-Muñoz, Damián.; Ramírez Mendoza, Ricardo
2015-04-01
The topic of this paper is the analysis of a control system for a semi active rear suspension in an off-road 2-wheel vehicle. Several control methods are studied, as well as the recently proposed Frequency Estimation Based (FEB) algorithm. The test motorcycle dynamics, as well as the passive, semi active, and the algorithm controlled shock absorber models are loaded into BikeSim, a professional two-wheeled vehicle simulation software, and tested in several road conditions. The results show a detailed comparison of the theoretical performance of the different control approaches in a novel environment for semi active dampers.
4. View of bridge deck from northeast approach (bridge deck ...
4. View of bridge deck from northeast approach (bridge deck from southwest approach is virtually identical - Big Cottonwood River Bridge No. 246, Spanning Big Cottonwood River at Cottonwood Street (City Road No. 165), New Ulm, Brown County, MN
Mechanized Off-Road Equipment Safety. Module SH-17. Safety and Health.
ERIC Educational Resources Information Center
Center for Occupational Research and Development, Inc., Waco, TX.
This student module on mechanized off-road equipment safety is one of 50 modules concerned with job safety and health. This module aims to encourage the development of a positive approach to safety as it concerns the heavy equipment industry. Following the introduction, 15 objectives (each keyed to a page in the text) the student is expected to…
A three-stage heuristic for harvest scheduling with access road network development
Mark M. Clark; Russell D. Meller; Timothy P. McDonald
2000-01-01
In this article we present a new model for the scheduling of forest harvesting with spatial and temporal constraints. Our approach is unique in that we incorporate access road network development into the harvest scheduling selection process. Due to the difficulty of solving the problem optimally, we develop a heuristic that consists of a solution construction stage...
Prioritizing environmental justice and equality: diesel emissions in southern California.
Marshall, Julian D; Swor, Kathryn R; Nguyen, Nam P
2014-04-01
Existing environmental policies aim to reduce emissions but lack standards for addressing environmental justice. Environmental justice research documents disparities in exposure to air pollution; however, little guidance currently exists on how to make improvements or on how specific emission-reduction scenarios would improve or deteriorate environmental justice conditions. Here, we quantify how emission reductions from specific sources would change various measures of environmental equality and justice. We evaluate potential emission reductions for fine diesel particulate matter (DPM) in Southern California for five sources: on-road mobile, off-road mobile, ships, trains, and stationary. Our approach employs state-of-the-science dispersion and exposure models. We compare four environmental goals: impact, efficiency, equality, and justice. Results indicate potential trade-offs among those goals. For example, reductions in train emissions produce the greatest improvements in terms of efficiency, equality, and justice, whereas off-road mobile source reductions can have the greatest total impact. Reductions in on-road emissions produce improvements in impact, equality, and justice, whereas emission reductions from ships would widen existing population inequalities. Results are similar for complex versus simplified exposure analyses. The approach employed here could usefully be applied elsewhere to evaluate opportunities for improving environmental equality and justice in other locations.
NASA Astrophysics Data System (ADS)
Qin, Yechen; He, Chenchen; Shao, Xinxin; Du, Haiping; Xiang, Changle; Dong, Mingming
2018-04-01
This paper presents a new approach for vibration mitigation based on a dynamic vibration absorbing structure (DVAS) for electric vehicles (EVs) that use in-wheel switched reluctance motors (SRMs). The proposed approach aims to alleviate the negative effects of vibration caused by the unbalanced electromagnetic force (UMEF) that arises from road excitations. The analytical model of SRMs is first formulated using Fourier series, and then a model of the coupled longitudinal-vertical dynamics is developed taking into consideration the external excitations consisting of the aerodynamic drag force and road unevenness. In addition, numerical simulations for a conventional SRM-suspension system and two novel DVASs are carried out for varying road levels specified by ISO standards and vehicle velocities. The results of the comparison reveal that a 35% improvement in ride comfort, 30% improvement of road handling, and 68% improvement in air gap between rotor and stator can be achieved by adopting the novel DVAS compared to the conventional SRM-suspension system. Finally, multi-body simulation (MBS) is performed using LMS Motion to validate the feasibility of the proposed DVAS. Analysis of the results shows that the proposed method can augment the effective application of SRMs in EVs.
Purcell, C; Romijn, A R
2017-11-01
In 2016, 29% of pedestrians killed or seriously injured on the roads in Great Britain were under 15 years of age. Children with Developmental Coordination Disorder (DCD), a chronic disorder affecting the acquisition and execution of motor skills, may be more vulnerable at the roadside than typically developing (TD) children. Current methods used to teach road safety are typically knowledge-based and do not necessarily improve behaviour in real traffic situations. Virtual reality road crossing tasks may be a viable alternative. The present study aimed to test the road crossing accuracy of children with and without DCD in virtual reality tasks that varied the viewpoint to simulate the teaching methods currently used in road safety educational programmes. Twenty-one children with DCD and twenty-one age and gender matched TD peers were required to locate the safest road crossing sites in two conditions: allocentric (aerial viewpoint) and egocentric (first-person viewpoint). All children completed both conditions and were required to navigate either themselves or an avatar across the road using the safest crossing route. The primary outcome was accuracy defined as the number of trials, out of 10, on which the child successfully identified and used the safest crossing route. Children with DCD performed equally poorly in both conditions, while TD children were significantly more accurate in the egocentric condition. This difference cannot be explained by self-reported prior road crossing education, practice or confidence. While TD children may benefit from the development of an egocentric virtual reality road crossing task, multimodal methods may be needed to effectively teach road safety to children with DCD. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.
Naturalistic Validation of an On-Road Driving Test of Older Drivers
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
South approach, looking north. The galvanized piping extends from the ...
South approach, looking north. The galvanized piping extends from the abutments across the length of the arch. - Weaverland Bridge, Quarry Road spanning Conestoga Creek, Terre Hill, Lancaster County, PA
Impact of traffic congestion on road accidents: a spatial analysis of the M25 motorway in England.
Wang, Chao; Quddus, Mohammed A; Ison, Stephen G
2009-07-01
Traffic congestion and road accidents are two external costs of transport and the reduction of their impacts is often one of the primary objectives for transport policy makers. The relationship between traffic congestion and road accidents however is not apparent and less studied. It is speculated that there may be an inverse relationship between traffic congestion and road accidents, and as such this poses a potential dilemma for transport policy makers. This study aims to explore the impact of traffic congestion on the frequency of road accidents using a spatial analysis approach, while controlling for other relevant factors that may affect road accidents. The M25 London orbital motorway, divided into 70 segments, was chosen to conduct this study and relevant data on road accidents, traffic and road characteristics were collected. A robust technique has been developed to map M25 accidents onto its segments. Since existing studies have often used a proxy to measure the level of congestion, this study has employed a precise congestion measurement. A series of Poisson based non-spatial (such as Poisson-lognormal and Poisson-gamma) and spatial (Poisson-lognormal with conditional autoregressive priors) models have been used to account for the effects of both heterogeneity and spatial correlation. The results suggest that traffic congestion has little or no impact on the frequency of road accidents on the M25 motorway. All other relevant factors have provided results consistent with existing studies.
A Wi-Fi based Electronic Road Sign for Enhancing the Awareness of Vehicle Driver
NASA Astrophysics Data System (ADS)
Bhawiyuga, A.; Sabriansyah, R. A.; Yahya, W.; E Putra, R.
2017-01-01
Reducing the road accident rate is one of the city goal in the area of transportation. One of the effort to reach that goal is done by deploying various signs across the road. However, the role of those road signs can be diminished once the vehicle drivers intentionally or unintentionally disobey the rule indicated on those signs. In order to increase the awareness of the driver, we can employ the vehicular network concept in which a vehicle can communicate with another vehicles or with the infrastructure installed along the road. For realizing that idea, we propose the implementation of communication equipped road sign system which consists of two components: Road Side Unit (RSU) module deployed at road sign and On Board Unit (OBU) module deployed at each vehicle. In our proposed scheme, both of the devices communicate each other through the widely-used Wi-Fi protocol (IEEE 802.11n) operating in ad-hoc mode. While a OBU equipped vehicle is moving towards the communication range of RSU, it will make an association to a predefined wireless ad-hoc network. Once it is associated, the OBU can receive message broadcast by the RSU. Upon reception, OBU display alert message indicating that the vehicle is approaching a road sign. From performance testing we observe that the proposed system can give relatively good service the vehicle moving as fast as speed 90km/h with the distance as far as 90m.
van Petegem, J W H Jan Hendrik; Wegman, Fred
2014-06-01
About 50% of all road traffic fatalities and 30% of all traffic injuries in the Netherlands take place on rural roads with a speed limit of 80 km/h. About 50% of these crashes are run-off-road (ROR) crashes. To reduce the number of crashes on this road type, attention should be put on improving the safety of the infrastructure of this road type. With the development of a crash prediction model for ROR crashes on rural roads with a speed limit of 80 km/h, this study aims at making a start in providing the necessary new tools for a proactive road safety policy to road administrators in the Netherlands. The paper presents a basic framework of the model development, comprising a problem description, the data used, and the method for developing the model. The model is developed with the utilization of generalized linear modeling in SAS, using the Negative Binomial probability distribution. A stepwise approach is used by adding one variable at a time, which forms the basis for striving for a parsimonious model and the evaluation of the model. The likelihood ratio test and the Akaike information criterion are used to assess the model fit, and parameter estimations are compared with literature findings to check for consistency. The results comprise two important outcomes. One is a crash prediction model (CPM) to estimate the relative safety of rural roads with a speed limit of 80 km/h in a network. The other is a small set of estimated effects of traffic volume and road characteristics on ROR crash frequencies. The results may lead to adjustments of the road design guidelines in the Netherlands and to further research on the quantification of risk factors with crash prediction models. Copyright © 2014 Elsevier Ltd. All rights reserved.
Making road safety a public health concern for policy-makers in India.
Dandona, Rakhi
2006-01-01
Road traffic injuries contribute substantially to the disease burden in India. This paper describes the road safety issues discussed by members of the Indian Parliament, and highlights the gaps that need to be addressed to make road safety visible as a public health problem to policy-makers in India. All questions asked to and information provided by the Ministry of Road Transport and Highways, and questions relating to accident asked to the Ministry of Health and Family Welfare of the Government of India were reviewed for the two Houses of the Indian Parliament for the years 2002 to 2004. Of the 1529 questions asked to the Ministry of Road Transport and Highways, only 140 (9.1%) were related to road safety, whereas 1076 (70.5%), 181 (11.8%), 51 (3.3%) and 81 (5.3%) were related to other aspects of the national highways, state roads, vehicles and other issues, respectively. Data on the magnitude of road crashes dealt only with the number of crashes and fatalities and not with the age, sex and type of road users affected by road traffic injuries. The parliamentarians were informed that human error was the main cause of road crashes in India; however, the robustness of this information is questionable. Strategies to prevent road crashes focused mainly on training of drivers with little attention to other factors that cause road crashes. The discussion on legislations also focused on drivers, ignoring other road users. Ten of the 4741 questions (0.2%) asked to Ministry of Health and Family Welfare were related to accident, the majority of which were about the setting up of trauma care services. An appropriate policy and intervention response by policy-makers is not possible with data that are presented in a manner that do not highlight the true nature of the problem, and are neither comprehensive nor robust. Majority of the proposed road safety interventions by the Ministry of Road Transport and Highways are based on the traditional view of human error as a major cause of road crashes highlighting the lack of a scientific public health approach towards prevention of road crashes. It would be useful to build the technical capacity of the Ministry of Road Transport and Highways in road safety to use the available data more effectively, and to facilitate generation of further relevant data about the magnitude, underlying causes and impact of road traffic injuries, for policy-makers to better understand the critical issues for planning effective road safety policies and interventions to reduce the high burden of mortality and morbidity due to road crashes in India.
NASA Astrophysics Data System (ADS)
Karlsson, Caroline; Miliutenko, Sofiia; Björklund, Anna; Mörtberg, Ulla; Olofsson, Bo; Toller, Susanna
2017-04-01
Environmental impacts during the life cycle stages of transport infrastructure are substantial, including among other greenhouse gas (GHG) emissions, as well as resource and energy use. For transport infrastructure to be sustainable, such issues need to be integrated in the planning process. Environmental Impact Assessment (EIA) is required by the European Union (EU) in order to ensure that all environmental aspects are considered during planning of road infrastructure projects. As a part of this process, the European Commission has suggested the use of the tool life cycle assessment (LCA) for assessing life cycle energy use and GHG emissions. When analyzing life cycle impacts of the road infrastructure itself, it was shown that earthworks and materials used for the road construction have a big share in the total energy use and GHG emissions. Those aspects are largely determined by the geological conditions at the site of construction: parameters such as soil thickness, slope, bedrock quality and soil type. The geological parameters determine the amounts of earthworks (i.e. volumes of soil and rock that will be excavated and blasted), transportation need for excavated materials as well as the availability of building materials. The study presents a new geographic information system (GIS)-based approach for utilizing spatial geological data in three dimensions (i.e. length, width and depth) in order to improve estimates on earthworks during the early stages of road infrastructure planning. Three main methodological steps were undertaken: mass balance calculation, life cycle inventory analysis and spatial mapping of greenhouse gas (GHG) emissions and energy use. The proposed GIS-based approach was later evaluated by comparing with the actual values of extracted material of a real road construction project. The results showed that the estimate of filling material was the most accurate, while the estimate for excavated soil and blasted rock had a wide variation from the actual values. It was also found that the total volume of excavated and ripped soils did not change when accounting for geological stratigraphy. The proposed GIS-based approach shows promising results for usage in LCA at an early stage of road infrastructure planning, and by providing better data quality, GIS in combination with LCA can enable planning for a more sustainable transport infrastructure.
Real-Time (Vision-Based) Road Sign Recognition Using an Artificial Neural Network.
Islam, Kh Tohidul; Raj, Ram Gopal
2017-04-13
Road sign recognition is a driver support function that can be used to notify and warn the driver by showing the restrictions that may be effective on the current stretch of road. Examples for such regulations are 'traffic light ahead' or 'pedestrian crossing' indications. The present investigation targets the recognition of Malaysian road and traffic signs in real-time. Real-time video is taken by a digital camera from a moving vehicle and real world road signs are then extracted using vision-only information. The system is based on two stages, one performs the detection and another one is for recognition. In the first stage, a hybrid color segmentation algorithm has been developed and tested. In the second stage, an introduced robust custom feature extraction method is used for the first time in a road sign recognition approach. Finally, a multilayer artificial neural network (ANN) has been created to recognize and interpret various road signs. It is robust because it has been tested on both standard and non-standard road signs with significant recognition accuracy. This proposed system achieved an average of 99.90% accuracy with 99.90% of sensitivity, 99.90% of specificity, 99.90% of f-measure, and 0.001 of false positive rate (FPR) with 0.3 s computational time. This low FPR can increase the system stability and dependability in real-time applications.
Real-Time (Vision-Based) Road Sign Recognition Using an Artificial Neural Network
Islam, Kh Tohidul; Raj, Ram Gopal
2017-01-01
Road sign recognition is a driver support function that can be used to notify and warn the driver by showing the restrictions that may be effective on the current stretch of road. Examples for such regulations are ‘traffic light ahead’ or ‘pedestrian crossing’ indications. The present investigation targets the recognition of Malaysian road and traffic signs in real-time. Real-time video is taken by a digital camera from a moving vehicle and real world road signs are then extracted using vision-only information. The system is based on two stages, one performs the detection and another one is for recognition. In the first stage, a hybrid color segmentation algorithm has been developed and tested. In the second stage, an introduced robust custom feature extraction method is used for the first time in a road sign recognition approach. Finally, a multilayer artificial neural network (ANN) has been created to recognize and interpret various road signs. It is robust because it has been tested on both standard and non-standard road signs with significant recognition accuracy. This proposed system achieved an average of 99.90% accuracy with 99.90% of sensitivity, 99.90% of specificity, 99.90% of f-measure, and 0.001 of false positive rate (FPR) with 0.3 s computational time. This low FPR can increase the system stability and dependability in real-time applications. PMID:28406471
Walker, Robert; Arima, Eugenio; Messina, Joe; Soares-Filho, Britaldo; Perz, Stephen; Vergara, Dante; Sales, Marcio; Pereira, Ritaumaria; Castro, Williams
2013-01-01
This article addresses the spatial decision-making of loggers and implications for forest fragmentation in the Amazon basin. It provides a behavioral explanation for fragmentation by modeling how loggers build road networks, typically abandoned upon removal of hardwoods. Logging road networks provide access to land, and the settlers who take advantage of them clear fields and pastures that accentuate their spatial signatures. In shaping agricultural activities, these networks organize emergent patterns of forest fragmentation, even though the loggers move elsewhere. The goal of the article is to explicate how loggers shape their road networks, in order to theoretically explain an important type of forest fragmentation found in the Amazon basin, particularly in Brazil. This is accomplished by adapting graph theory to represent the spatial decision-making of loggers, and by implementing computational algorithms that build graphs interpretable as logging road networks. The economic behavior of loggers is conceptualized as a profit maximization problem, and translated into spatial decision-making by establishing a formal correspondence between mathematical graphs and road networks. New computational approaches, adapted from operations research, are used to construct graphs and simulate spatial decision-making as a function of discount rates, land tenure, and topographic constraints. The algorithms employed bracket a range of behavioral settings appropriate for areas of terras de volutas, public lands that have not been set aside for environmental protection, indigenous peoples, or colonization. The simulation target sites are located in or near so-called Terra do Meio, once a major logging frontier in the lower Amazon Basin. Simulation networks are compared to empirical ones identified by remote sensing and then used to draw inferences about factors influencing the spatial behavior of loggers. Results overall suggest that Amazonia's logging road networks induce more fragmentation than necessary to access fixed quantities of wood. The paper concludes by considering implications of the approach and findings for Brazil's move to a system of concession logging.
NASA Astrophysics Data System (ADS)
Schmidt, A.; Rella, C.; Goeckede, M.; Hanson, C. V.; Yang, Z.; Law, B. E.
2014-12-01
In recent years, measurements of atmospheric carbon dioxide with high precision and accuracy have become increasingly important for climate change research, in particular to inform terrestrial biosphere models. Anthropogenic carbon dioxide emissions from fossil fuel burning have long been recognized to contribute a significant portion of the carbon dioxide in the atmosphere. Here, we present an approach to remove the traffic related carbon dioxide emissions from mole fractions measured at a tall tower by using the corresponding carbon monoxide measurements in combination with footprint analyses and transport modeling. This technique improves the suitability of the CO2 data to be used in inverse modeling approaches of atmosphere-biosphere exchange that do not account for non-biotic portions of CO2. In our study region in Oregon, road traffic emissions are the biggest source of anthropogenic carbon dioxide and carbon monoxide. A three-day mobile campaign covering 1700 km of roads in northwestern Oregon was performed during summer of 2012 using a laser-based Cavity Ring Down Spectrometer. The mobile measurements incorporated different roads including main highways, urban streets, and back-roads, largely within the typical footprint of a tall CO2 observation tower in Oregon's Willamette Valley. For the first time, traffic related CO:CO2 emission ratios were measured directly at the sources during an on-road campaign under a variety of different driving conditions. An average emission ratio of 7.43 (±1.80) ppb CO per ppm CO2 was obtained for the study region and applied to separate the traffic related portion of CO2 from the mole fraction time series. The road traffic related portion of the CO2 mole fractions measured at the tower site reached maximum values from 9.8 to 12 ppm, depending on the height above the surface, during summer 2012.
NASA Astrophysics Data System (ADS)
Owen, Karen K.
This research addresses the need for reliable, repeatable, quantitative measures to differentiate informal (slum) from formal (planned) settlements using commercial very high resolution imagery and elevation data. Measuring the physical, spatial and spectral qualities of informal settlements is an important precursor for evaluating success toward improving the lives of 100 million slum dwellers worldwide, as pledged by the United Nations Millennium Development Goal Target 7D. A variety of measures were tested based on surface material spectral properties, texture, built-up structure, road network accessibility, and geomorphology from twelve communities in Guatemala City to reveal statistically significant differences between informal and formal settlements that could be applied to other parts of the world without the need for costly or dangerous field surveys. When information from satellite imagery is constrained to roads and residential boundaries, a more precise understanding of human habitation is produced. A classification and regression tree (CART) approach and linear discriminant function analysis enabled a variable dimensionality reduction from the original 23 to 6 variables that are sufficient to differentiate a settlement as informal or formal. The results demonstrate that the entropy texture of roads, the degree of asphalt road surface, the vegetation patch compactness and patch size, the percent of bare soil land cover, the geomorphic profile convexity of the terrain, and the road density distinguish informal from formal settlements with 87--92% accuracy when results are cross-validated. The variables with highest contribution to model outcome that are common to both approaches are entropy texture of roads, vegetation patch size, and vegetation compactness suggesting that road texture, surface materials and vegetation provide the necessary characteristics to distinguish the level of informality of a settlement. The results will assist urban planners and settlement analysts who must process vast amounts of imagery worldwide, enabling them to report annually on slum conditions. An added benefit is the ability to use the measures in data-poor regions of the world without field surveys.
Shukla, Nagesh; Wickramasuriya, Rohan; Miller, Andrew; Perez, Pascal
2015-11-01
This paper proposes an integrated modelling approach for location planning of radiotherapy treatment services based on cancer incidence and road network-based accessibility. Previous research efforts have established travel distance/time barriers as a key factor affecting access to cancer treatment services, as well as epidemiological studies have shown that cancer incidence rates vary with population demography. Our study is built on the evidence that the travel distances to treatment centres and demographic profiles of the accessible regions greatly influence the uptake of cancer radiotherapy (RT) services. An integrated service planning approach that combines spatially-explicit cancer incidence projections, and the placement of new RT services based on road network based accessibility measures have never been attempted. This research presents a novel approach for the location planning of RT services, and demonstrates its viability by modelling cancer incidence rates for different age-sex groups in New South Wales, Australia based on observed cancer incidence trends; and estimations of the road network-based access to current NSW treatment centres. Using three indices (General Efficiency, Service Availability and Equity), we show how the best location for a new RT centre may be chosen when there are multiple competing locations. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Jing, B. Y.; Wu, L.; Mao, H. J.; Gong, S. L.; He, J. J.; Zou, C.; Song, G. H.; Li, X. Y.; Wu, Z.
2015-10-01
As the ownership of vehicles and frequency of utilization increase, vehicle emissions have become an important source of air pollution in Chinese cities. An accurate emission inventory for on-road vehicles is necessary for numerical air quality simulation and the assessment of implementation strategies. This paper presents a bottom-up methodology based on the local emission factors, complemented with the widely used emission factors of Computer Programme to Calculate Emissions from Road Transport (COPERT) model and near real time (NRT) traffic data on road segments to develop a high temporal-spatial resolution vehicle emission inventory (HTSVE) for the urban Beijing area. To simulate real-world vehicle emissions accurately, the road has been divided into segments according to the driving cycle (traffic speed) on this road segment. The results show that the vehicle emissions of NOx, CO, HC and PM were 10.54 × 104, 42.51 × 104 and 2.13 × 104 and 0.41 × 104 Mg, respectively. The vehicle emissions and fuel consumption estimated by the model were compared with the China Vehicle Emission Control Annual Report and fuel sales thereafter. The grid-based emissions were also compared with the vehicular emission inventory developed by the macro-scale approach. This method indicates that the bottom-up approach better estimates the levels and spatial distribution of vehicle emissions than the macro-scale method, which relies on more information. Additionally, the on-road vehicle emission inventory model and control effect assessment system in Beijing, a vehicle emission inventory model, was established based on this study in a companion paper (He et al., 2015).
Implementing evidence-based policy in a network setting: road safety policy in the Netherlands.
Bax, Charlotte; de Jong, Martin; Koppenjan, Joop
2010-01-01
In the early 1990s, in order to improve road safety in The Netherlands, the Institute for Road Safety Research (SWOV) developed an evidence-based "Sustainable Safety" concept. Based on this concept, Dutch road safety policy, was seen as successful and as a best practice in Europe. In The Netherlands, the policy context has now changed from a sectoral policy setting towards a fragmented network in which safety is a facet of other transport-related policies. In this contribution, it is argued that the implementation strategy underlying Sustainable Safety should be aligned with the changed context. In order to explore the adjustments needed, two perspectives of policy implementation are discussed: (1) national evidence-based policies with sectoral implementation; and (2) decentralized negotiation on transport policy in which road safety is but one aspect. We argue that the latter approach matches the characteristics of the newly evolved policy context best, and conclude with recommendations for reformulating the implementation strategy.
Multiresolution texture analysis applied to road surface inspection
NASA Astrophysics Data System (ADS)
Paquis, Stephane; Legeay, Vincent; Konik, Hubert; Charrier, Jean
1999-03-01
Technological advances provide now the opportunity to automate the pavement distress assessment. This paper deals with an approach for achieving an automatic vision system for road surface classification. Road surfaces are composed of aggregates, which have a particular grain size distribution and a mortar matrix. From various physical properties and visual aspects, four road families are generated. We present here a tool using a pyramidal process with the assumption that regions or objects in an image rise up because of their uniform texture. Note that the aim is not to compute another statistical parameter but to include usual criteria in our method. In fact, the road surface classification uses a multiresolution cooccurrence matrix and a hierarchical process through an original intensity pyramid, where a father pixel takes the minimum gray level value of its directly linked children pixels. More precisely, only matrix diagonal is taken into account and analyzed along the pyramidal structure, which allows the classification to be made.
Manole, M; Ciuhodaru, T; Zanoschi, Georgeta; Manole, Alina; Ivan, A
2011-01-01
The aim of study was to assess road traffic injuries in relation with their localisation and severity. A sample of 3521 patients suffering from road traffic injuries and assisted in "Sf. Ioan" Emergency Unit, Iaşi, Romania was assess regarding age group, sex and residence area, type of lesions and ther localisation and severity, between 2002-2009. Data were collected using a special epidemiological inquiry and processed using SPSS and MS Excel statistical softs. The incidence of road traffic injuries increased during the last decade, with a report men/women of 1.5, urban and 21-30 age group predominance. The most frequent were leg fractures (16.7%) and thoracal contusions (19.1%), cranial and facial trauma (32.4%), with open injuries (10.5%). Prevention programmes with a high efficiency at the national level, as well as a concret identification of risk factors with a multidisciplinar approach of road traffic accidents, are needed.
a Novel Approach to Camera Calibration Method for Smart Phones Under Road Environment
NASA Astrophysics Data System (ADS)
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.
McDonald, Brian C; Goldstein, Allen H; Harley, Robert A
2015-04-21
A fuel-based approach is used to assess long-term trends (1970-2010) in mobile source emissions of black carbon (BC) and organic aerosol (OA, including both primary emissions and secondary formation). The main focus of this analysis is the Los Angeles Basin, where a long record of measurements is available to infer trends in ambient concentrations of BC and organic carbon (OC), with OC used here as a proxy for OA. Mobile source emissions and ambient concentrations have decreased similarly, reflecting the importance of on- and off-road engines as sources of BC and OA in urban areas. In 1970, the on-road sector accounted for ∼90% of total mobile source emissions of BC and OA (primary + secondary). Over time, as on-road engine emissions have been controlled, the relative importance of off-road sources has grown. By 2010, off-road engines were estimated to account for 37 ± 20% and 45 ± 16% of total mobile source contributions to BC and OA, respectively, in the Los Angeles area. This study highlights both the success of efforts to control on-road emission sources, and the importance of considering off-road engine and other VOC source contributions when assessing long-term emission and ambient air quality trends.
Road-networks, a practical indicator of human impacts on biodiversity in Tropical forests
NASA Astrophysics Data System (ADS)
Hosaka, T.; Yamada, T.; Okuda, T.
2014-02-01
Tropical forests sustain the most diverse plants and animals in the world, but are also being lost most rapidly. Rapid assessment and monitoring using remote sensing on biodiversity of tropical forests is needed to predict and evaluate biodiversity loss by human activities. Identification of reliable indicators of forest biodiversity and/or its loss is an urgent issue. In the present paper, we propose the density of road networks in tropical forests can be a good and practical indicator of human impacts on biodiversity in tropical forests through reviewing papers and introducing our preliminary survey in peninsular Malaysia. Many previous studies suggest a strong negative impact of forest roads on biodiversity in tropical rainforests since they changes microclimate, soil properties, drainage patterns, canopy openness and forest accessibility. Moreover, our preliminary survey also showed that even a narrow logging road (6 m wide) significantly lowered abundance of dung beetles (well-known bio-indicator in biodiversity survey in tropical forests) near the road. Since these road networks are readily to be detected with remote sensing approach such as aerial photographs and Lider, regulation and monitoring of the road networks using remote sensing techniques is a key to slow down the rate of biodiversity loss due to forest degradation in tropical forests.
A framework of analysis for field experiments with alternative materials in road construction.
François, D; Jullien, A
2009-01-01
In France, a wide variety of alternative materials is produced or exists in the form of stockpiles built up over time. Such materials are distributed over various regions of the territory depending on local industrial development and urbanisation trends. The use of alternative materials at a national scale implies sharing local knowledge and experience. Building a national database on alternative materials for road construction is useful in gathering and sharing information. An analysis of feedback from onsite experiences (back analysis) is essential to improve knowledge on alternative material use in road construction. Back analysis of field studies has to be conducted in accordance with a single common framework. This could enable drawing comparisons between alternative materials and between road applications. A framework for the identification and classification of data used in back analyses is proposed. Since the road structure is an open system, this framework has been based on a stress-response approach at both the material and structural levels and includes a description of external factors applying during the road service life. The proposal has been shaped from a review of the essential characteristics of road materials and structures, as well as from the state of knowledge specific to alternative material characterisation.
Using TerraSAR-X satellite data to detect road age and degradation
NASA Astrophysics Data System (ADS)
Necsoiu, Marius; Longepe, Nicolas; Parra, Jorge O.; Walter, Gary R.
2017-05-01
Analysis of satellite-acquired synthetic aperture radar (SAR) data provides a way to rapidly survey road conditions over large areas. This capability could be useful for identifying road segments that potentially require repair or at least onsite inspection of their condition due to changes in vehicular traffic associated with change in land use. We conducted a feasibility study focused on urban roads near the Southwest Research Institute (SwRI) campus in San Antonio, Texas. The roads near SwRI were affected by heavy truck traffic, they were easily inspected, and the age and construction of the pavement was known. TerraSAR-X (TSX) SpotLight (ST) satellite data were used to correlate radar backscattering response to pavement age and condition. Our preliminary results indicate that TSX radar imagery can be useful for detecting changes in pavement type, damage to pavement, such as cracking and scaling, and, occasionally, severe rutting. In addition, multitemporal interferometric analysis showed patches of settlement along two roads south of the SwRI campus. Further development of an automated approach to detect degradation of roads could allow transportation departments to prioritize inspection and repair efforts. The techniques also could be used to detect surreptitious heavy truck traffic in areas where direct inspection is not possible.
A.J. Lang; W.M. Aust; M.C. Bolding; E.B. Schilling
2016-01-01
Ditched forest roads leading to stream crossings and used for log transportation have recently been a topic of water quality concern and legal controversy. Best management practices (BMPs) can reduce potential water quality issues, yet few research studies have quantified BMP costs and reductions in sediment from implementing specific ditch BMPs. Researchers...
Elvik, Rune
2017-09-01
In several papers, Hauer (1988, 1989, 2000a, 2000b, 2016) has argued that the level of safety built into roads is unpremeditated, i.e. not the result of decisions based on knowledge of the safety impacts of design standards. Hauer has pointed out that the development of knowledge about the level of safety built into roads has been slow and remains incomplete even today. Based on these observations, this paper asks whether evolutionary theory can contribute to explaining the slow development of knowledge. A key proposition of evolutionary theory is that knowledge is discovered through a process of learning-by-doing; it is not necessarily produced intentionally by means of research or development. An unintentional discovery of knowledge is treacherous as far as road safety is concerned, since an apparently effective safety treatment may simply be the result of regression-to-the-mean. The importance of regression-to-the-mean was not fully understood until about 1980, and a substantial part of what was regarded as known at that time may have been based on studies not controlling for regression-to-the-mean. An attempt to provide an axiomatic foundation for designing a safe road system was made by Gunnarsson and Lindström (1970). This had the ambition of providing universal guidelines that would facilitate a preventive approach, rather than the reactive approach based on accident history (i.e. designing a system known to be safe, rather than reacting to events in a system of unknown safety). Three facts are notable about these principles. First, they are stated in very general terms and do not address many of the details of road design or traffic control. Second, they are not based on experience showing their effectiveness. Third, they are partial and do not address the interaction between elements of the road traffic system, in particular road user adaptation to system design. Another notable fact consistent with evolutionary theory, is that the safety margins built into various design elements have been continuously eroded by the development of bigger and faster motor vehicles, that can only be operated safely if roads are wider and straighter than they needed to be when motor vehicles were smaller and moved slower. Copyright © 2017 Elsevier Ltd. All rights reserved.
Safety and driver behavior studies at multiple lane approaches to stop-controlled intersections.
DOT National Transportation Integrated Search
2010-05-01
Multiple-lane approaches (MLAs) controlled by stop signs are becoming increasingly common in Nebraska. Installation of MLAs occurs when a single approach lane can no longer adequately serve the minor road traffic volume, and a signal is unwarranted b...
3. VIEW LOOKING WEST OF APPROACH TO THE BRIDGE AND ...
3. VIEW LOOKING WEST OF APPROACH TO THE BRIDGE AND INCLUDING SCENES OF THE SURROUNDING RURAL ENVIRONMENT. - Madison County Bridge 90, Spanning Killbuck Creek on County Road No. 600, Moonville, Madison County, IN
Moussa, Tarek A A; Al-Zahrani, Hassan S; Almaghrabi, Omar A; Abdelmoneim, Tamer S; Fuller, Michael P
2017-01-01
A total of 145007 reads were obtained from pyrosequencing for all the 4 samples. The total count ranged from 11,301,014 (Mecca old road) to 23,503,512 bp (Thuwal). A total of 460 fungal species belonging to 133 genera, 58 families, 33 orders, 13 classes and 4 phyla was identified across the four sites. The most abundant phylum at all four sites was Ascomycota followed by Basidiomycota. Four phyla (Ascomycota-99.31%, Basidiomycota-0.59%, Chytridiomycota-0.04%, Glomeromycota-0.03%) were detected in Khulais. Except for Glomeromycota, all phyla were detected at Mecca old road (Ascomycota-74.26%, Basidiomycota-25.71%, Chytridiomycota-0.01%) and Thuwal (Ascomycota-99.59%, Basidiomycota-0.40%, Chytridiomycota-0.002%); while only Ascomycota-90.98% and Basidiomycota-9.01% were detected in Asfan road. At the class level, Sordariomycetes was predominantly observed at Asfan road-59.88%, Khulais-68.26% and Thuwal-94.84%; while Pezizomycetes was dominant at Mecca old road-56.01%, was absent at Asfan road. Agaricomycetes was present only at Mecca old road-25.73%; while Tremellomycetes-5.77%, Malasseizomycetes-2.13% and Microbotryomycetes-1.10% were found only at Asfan road. The phylogenetic trees revealed that clear genus level differences are visible across all the four sites, with an overall predominance of Thielavia followed by Madurella, Aspergillus, and Gelasinospora. Chaetomium sp., Aspergillus caespitosus and Aspergillus sp. were found in moderate (Mecca old road and Thuwal) to abundant (Asfan road and Khulais) quantities. Thielavia sp., Thielavia hyalocarpa and Madurella sp. are found in moderate quantities at Khulais and Mecca old road, while in abundant levels at Asfan road and Thuwal. Fusarium equisati and F. oxysporum were detected at Thuwal and Khulais. Sordaria araneosa was present at Khulais, while Malasseiza globosa species was detected in moderate quantities across all sites except Khulais.
Understanding congested travel in urban areas
Çolak, Serdar; Lima, Antonio; González, Marta C.
2016-01-01
Rapid urbanization and increasing demand for transportation burdens urban road infrastructures. The interplay of number of vehicles and available road capacity on their routes determines the level of congestion. Although approaches to modify demand and capacity exist, the possible limits of congestion alleviation by only modifying route choices have not been systematically studied. Here we couple the road networks of five diverse cities with the travel demand profiles in the morning peak hour obtained from billions of mobile phone traces to comprehensively analyse urban traffic. We present that a dimensionless ratio of the road supply to the travel demand explains the percentage of time lost in congestion. Finally, we examine congestion relief under a centralized routing scheme with varying levels of awareness of social good and quantify the benefits to show that moderate levels are enough to achieve significant collective travel time savings. PMID:26978719
An Approach for Economic Analysis of Intermodal Transportation
Sahin, Bahri; Ust, Yasin; Guneri, Ali Fuat; Gulsun, Bahadir; Turan, Eda
2014-01-01
A different intermodal transportation model based on cost analysis considering technical, economical, and operational parameters is presented. The model consists of such intermodal modes as sea-road, sea-railway, road-railway, and multimode of sea-road-railway. A case study of cargo transportation has been carried out by using the suggested model. Then, the single road transportation mode has been compared to intermodal modes in terms of transportation costs. This comparison takes into account the external costs of intermodal transportation. The research reveals that, in the short distance transportation, single transportation modes always tend to be advantageous. As the transportation distance gets longer, intermodal transportation advantages begin to be effective on the costs. In addition, the proposed method in this study leads to determining the fleet size and capacity for transportation and the appropriate transportation mode. PMID:25152919
Understanding congested travel in urban areas
NASA Astrophysics Data System (ADS)
Çolak, Serdar; Lima, Antonio; González, Marta C.
2016-03-01
Rapid urbanization and increasing demand for transportation burdens urban road infrastructures. The interplay of number of vehicles and available road capacity on their routes determines the level of congestion. Although approaches to modify demand and capacity exist, the possible limits of congestion alleviation by only modifying route choices have not been systematically studied. Here we couple the road networks of five diverse cities with the travel demand profiles in the morning peak hour obtained from billions of mobile phone traces to comprehensively analyse urban traffic. We present that a dimensionless ratio of the road supply to the travel demand explains the percentage of time lost in congestion. Finally, we examine congestion relief under a centralized routing scheme with varying levels of awareness of social good and quantify the benefits to show that moderate levels are enough to achieve significant collective travel time savings.
An approach for economic analysis of intermodal transportation.
Sahin, Bahri; Yilmaz, Huseyin; Ust, Yasin; Guneri, Ali Fuat; Gulsun, Bahadir; Turan, Eda
2014-01-01
A different intermodal transportation model based on cost analysis considering technical, economical, and operational parameters is presented. The model consists of such intermodal modes as sea-road, sea-railway, road-railway, and multimode of sea-road-railway. A case study of cargo transportation has been carried out by using the suggested model. Then, the single road transportation mode has been compared to intermodal modes in terms of transportation costs. This comparison takes into account the external costs of intermodal transportation. The research reveals that, in the short distance transportation, single transportation modes always tend to be advantageous. As the transportation distance gets longer, intermodal transportation advantages begin to be effective on the costs. In addition, the proposed method in this study leads to determining the fleet size and capacity for transportation and the appropriate transportation mode.
The impact of climate change on winter road maintenance and traffic accidents in West Midlands, UK.
Andersson, Anna K; Chapman, Lee
2011-01-01
Winter weather can be a significant cause of road traffic accidents. This paper uses UKCIP climate change scenarios and a temporal analogue to investigate the relationship between temperature and severe road accidents in the West Midlands, UK. This approach also allows quantification of the changes in the severity of the winter season over the next century in the region. It is demonstrated that the predicted reduction in the number of frost days should in turn reduce the number of road accidents caused due to slipperiness by approximately 50%. However, the paper concludes by warning against complacency in winter maintenance regimes. A warmer climate may result in budget cuts for highway maintenance which in turn may well reverse declining accident trends. Copyright © 2010 Elsevier Ltd. All rights reserved.
The impact of traffic sign deficit on road traffic accidents in Nigeria.
Ezeibe, Christian; Ilo, Chukwudi; Oguonu, Chika; Ali, Alphonsus; Abada, Ifeanyi; Ezeibe, Ezinwanne; Oguonu, Chukwunonso; Abada, Felicia; Izueke, Edwin; Agbo, Humphrey
2018-04-04
This study assesses the impact of traffic sign deficit on road traffic accidents in Nigeria. The participants were 720 commercial vehicle drivers. While simple random sampling was used to select 6 out of 137 federal highways, stratified random sampling was used to select six categories of commercial vehicle drivers. The study used qual-dominant mixed methods approach comprising key informant interviews; group interviews; field observation; policy appraisal and secondary literature on traffic signs. Result shows that the failure of government to provide and maintain traffic signs in order to guide road users through the numerous accident black spots on the highways is the major cause of road accidents in Nigeria. The study argues that provision and maintenance of traffic signs present opportunity to promoting safety on the highways and achieving the sustainable development goals.
Bailleul, Diane; Ollier, Sébastien; Huet, Sylvie; Gardarin, Antoine; Lecomte, Jane
2012-01-01
Anthropogenic vectors enhance the natural dispersal capacity of plant seeds significantly in terms of quantity and distance. Human-mediated seed dispersal (i.e. anthropochory) greatly increases the dispersal of crop species across agroecosystems. In the case of oilseed rape (OSR), spillage of seeds from grain trailers during harvest has never been quantified. Our experimental approach involved establishing 85 seed trap-sites on the road verges of an agricultural area around the grain silo of Selommes (Loir-et-Cher, France). We recorded OSR spillage during harvest and applied a linear model to the data. The amount of seed spilled was related positively to the area of the OSR fields served by the road, whereas the amount of seed spilled decreased with other variables, such as distance from the trap-site to the verge of the road and to the nearest field. The distance to the grain silo, through local and regional effects, affected seed loss. Local effects from fields adjacent to the road resulted in a cumulative spillage on one-lane roads. On two-lane roads, spillage was nearly constant whatever the distance to the silo due to a mixture of these local effects and of grain trailers that joined the road from more distant fields. From the data, we predicted the number of seeds lost from grain trailers on one road verge in the study area. We predicted a total spillage of 2.05 × 10(6) seeds (± 4.76 × 10(5)) along the road length, which represented a mean of 404 ± 94 seeds per m(2). Containment of OSR seeds will always be challenging. However, seed spillage could be reduced if grain trailers were covered and filled with less seed. Reducing distances travelled between fields and silos could also limit seed loss.
Large scale Wyoming transportation data: a resource planning tool
O'Donnell, Michael S.; Fancher, Tammy S.; Freeman, Aaron T.; Ziegler, Abra E.; Bowen, Zachary H.; Aldridge, Cameron L.
2014-01-01
The U.S. Geological Survey Fort Collins Science Center created statewide roads data for the Bureau of Land Management Wyoming State Office using 2009 aerial photography from the National Agriculture Imagery Program. The updated roads data resolves known concerns of omission, commission, and inconsistent representation of map scale, attribution, and ground reference dates which were present in the original source data. To ensure a systematic and repeatable approach of capturing roads on the landscape using on-screen digitizing from true color National Agriculture Imagery Program imagery, we developed a photogrammetry key and quality assurance/quality control protocols. Therefore, the updated statewide roads data will support the Bureau of Land Management’s resource management requirements with a standardized map product representing 2009 ground conditions. The updated Geographic Information System roads data set product, represented at 1:4,000 and +/- 10 meters spatial accuracy, contains 425,275 kilometers within eight attribute classes. The quality control of these products indicated a 97.7 percent accuracy of aspatial information and 98.0 percent accuracy of spatial locations. Approximately 48 percent of the updated roads data was corrected for spatial errors of greater than 1 meter relative to the pre-existing road data. Twenty-six percent of the updated roads involved correcting spatial errors of greater than 5 meters and 17 percent of the updated roads involved correcting spatial errors of greater than 9 meters. The Bureau of Land Management, other land managers, and researchers can use these new statewide roads data set products to support important studies and management decisions regarding land use changes, transportation and planning needs, transportation safety, wildlife applications, and other studies.
A method for mapping flood hazard along roads.
Kalantari, Zahra; Nickman, Alireza; Lyon, Steve W; Olofsson, Bo; Folkeson, Lennart
2014-01-15
A method was developed for estimating and mapping flood hazard probability along roads using road and catchment characteristics as physical catchment descriptors (PCDs). The method uses a Geographic Information System (GIS) to derive candidate PCDs and then identifies those PCDs that significantly predict road flooding using a statistical modelling approach. The method thus allows flood hazards to be estimated and also provides insights into the relative roles of landscape characteristics in determining road-related flood hazards. The method was applied to an area in western Sweden where severe road flooding had occurred during an intense rain event as a case study to demonstrate its utility. The results suggest that for this case study area three categories of PCDs are useful for prediction of critical spots prone to flooding along roads: i) topography, ii) soil type, and iii) land use. The main drivers among the PCDs considered were a topographical wetness index, road density in the catchment, soil properties in the catchment (mainly the amount of gravel substrate) and local channel slope at the site of a road-stream intersection. These can be proposed as strong indicators for predicting the flood probability in ungauged river basins in this region, but some care is needed in generalising the case study results other potential factors are also likely to influence the flood hazard probability. Overall, the method proposed represents a straightforward and consistent way to estimate flooding hazards to inform both the planning of future roadways and the maintenance of existing roadways. Copyright © 2013 Elsevier Ltd. All rights reserved.
Hubbard, Kaylan A.; Chalfoun, Anna D.; Gerow, Kenneth G.
2016-01-01
As road networks continue to expand globally, indirect impacts to adjacent wildlife populations remain largely unknown. Simultaneously, reptile populations are declining worldwide and anthropogenic habitat loss and fragmentation are frequently cited causes. We evaluated the relative influence of three different road characteristics (surface treatment, width, and traffic volume) and habitat features on adjacent populations of Northern Sagebrush Lizards (Sceloporus graciosus graciosus), Plateau Fence Lizards (S. tristichus), and Greater Short-Horned Lizards (Phrynosoma hernandesi) in mixed arid shrubland habitats in southwest Wyoming. Neither odds of lizard presence nor relative abundance was significantly related to any of the assessed road characteristics, although there was a trend for higher Sceloporus spp. abundance adjacent to paved roads. Sceloporus spp. relative abundance did not vary systematically with distance to the nearest road. Rather, both Sceloporus spp. and Greater Short-Horned Lizards were associated strongly with particular habitat characteristics adjacent to roads. Sceloporus spp. presence and relative abundance increased with rock cover, relative abundance was associated positively with shrub cover, and presence was associated negatively with grass cover. Greater Short-Horned Lizard presence increased with bare ground and decreased marginally with shrub cover. Our results suggest that habitat attributes are stronger correlates of lizard presence and relative abundance than individual characteristics of adjacent roads, at least in our system. Therefore, an effective conservation approach for these species may be to consider the landscape through which new roads and their associated development would occur, and the impact that placement could have on fragment size and key habitat elements.
Emissions from vehicles, tailpipe and vehicle re-entrained road dust
NASA Astrophysics Data System (ADS)
Zhu, Dongzi
Emissions from transportation are some of the largest sources of urban air pollution. Transportation emissions originate from both the engine-through combustion processes and non-tailpipe re-suspended road dust emissions induced by vehicle travel on unpaved and paved roads. Gaseous and particulate emissions from transportation sources have negative impacts on human health, visibility and may influence the global radiation balance. Fugitive dust emissions originating from vehicle travel on paved and unpaved roads constitute a significant fraction of the PM10 in many areas of the western US impacting their attainment status of National Ambient Air Quality Standards. The research used three novel instrument platforms developed at the Desert Research Institute. The In-Plume Emissions Test Stand (IPETS) was designed to provide characterization of exhaust emissions from in-use individual vehicles or engines by analyzing air as close as 1 m from the exhaust port. Real-world emission factors can be quantified by in-plume measurements and provide more realistic measures for emission inventories, source modeling, and receptor modeling than certification measurements. The Testing Re-entrained Aerosol Kinetic Emissions from Roads (TRAKER) provides an effective alternate approach to the EPA AP-42 road dust emissions estimation techniques by sampling 1000s of km of roads versus isolated 3 m sections. The Portable Deposition Monitoring Platform (PDMP incorporates PM and meteorological instruments to characterize the downwind change in particle concentrations to define depositional losses in different environments. The research outcome provides important knowledge for understanding diesel engine emissions, road dust emissions and aerosol deposition process near road sources.
MobRISK: a model for assessing the exposure of road users to flash flood events
NASA Astrophysics Data System (ADS)
Shabou, Saif; Ruin, Isabelle; Lutoff, Céline; Debionne, Samuel; Anquetin, Sandrine; Creutin, Jean-Dominique; Beaufils, Xavier
2017-09-01
Recent flash flood impact studies highlight that road networks are often disrupted due to adverse weather and flash flood events. Road users are thus particularly exposed to road flooding during their daily mobility. Previous exposure studies, however, do not take into consideration population mobility. Recent advances in transportation research provide an appropriate framework for simulating individual travel-activity patterns using an activity-based approach. These activity-based mobility models enable the prediction of the sequence of activities performed by individuals and locating them with a high spatial-temporal resolution. This paper describes the development of the MobRISK microsimulation system: a model for assessing the exposure of road users to extreme hydrometeorological events. MobRISK aims at providing an accurate spatiotemporal exposure assessment by integrating travel-activity behaviors and mobility adaptation with respect to weather disruptions. The model is applied in a flash-flood-prone area in southern France to assess motorists' exposure to the September 2002 flash flood event. The results show that risk of flooding mainly occurs in principal road links with considerable traffic load. However, a lag time between the timing of the road submersion and persons crossing these roads contributes to reducing the potential vehicle-related fatal accidents. It is also found that sociodemographic variables have a significant effect on individual exposure. Thus, the proposed model demonstrates the benefits of considering spatiotemporal dynamics of population exposure to flash floods and presents an important improvement in exposure assessment methods. Such improved characterization of road user exposures can present valuable information for flood risk management services.
NASA Astrophysics Data System (ADS)
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 informed other road development schemes in Nepal. Geomorphological surveys and robust geo-hazard assessments that factor the spatial and temporal dimensions of the seismic, fluvial and sediment hazards along the road corridor are critical for sustainable development of mountain roads. However, scientific and technical research studies seldom inform mountain road development primarily due to lack of co-ordination between the respective government agencies, access to journal papers in developing countries and unwillingness to adopt novel interventions in rural road construction practices. These challenges are further exacerbated by weak governance and lack of proper policy enforcement that often leads to construction of poorly engineered roads, thereby increasing the risk of rural infrastructural damage from geo-hazards. Though there exists a disconnect between the science-policy-governance interface where information on geo-hazards is neglected in mountain road development due to lack of scientific research and government apathy, there is an opportunity to spur dialogue and sensitize these issues via trans-disciplinary approaches on disaster risk management.
Bridge rail and approach railing for low-volume roads in Iowa : tech transfer summary, March 2010.
DOT National Transportation Integrated Search
2010-03-01
The primary objective of the research summarized below was to describe the state of the practice regarding the nations bridge rails and approach guardrails and to perform a statewide crash analysis involving bridge rails and approach guardrails on...
NASA Astrophysics Data System (ADS)
Fujiwara, Yukihiro; Yoshii, Masakazu; Arai, Yasuhito; Adachi, Shuichi
Advanced safety vehicle(ASV)assists drivers’ manipulation to avoid trafic accidents. A variety of researches on automatic driving systems are necessary as an element of ASV. Among them, we focus on visual feedback approach in which the automatic driving system is realized by recognizing road trajectory using image information. The purpose of this paper is to examine the validity of this approach by experiments using a radio-controlled car. First, a practical image processing algorithm to recognize white lines on the road is proposed. Second, a model of the radio-controlled car is built by system identication experiments. Third, an automatic steering control system is designed based on H∞ control theory. Finally, the effectiveness of the designed control system is examined via traveling experiments.
Modeling Of In-Vehicle Human Exposure to Ambient Fine Particulate Matter
Liu, Xiaozhen; Frey, H. Christopher
2012-01-01
A method for estimating in-vehicle PM2.5 exposure as part of a scenario-based population simulation model is developed and assessed. In existing models, such as the Stochastic Exposure and Dose Simulation model for Particulate Matter (SHEDS-PM), in-vehicle exposure is estimated using linear regression based on area-wide ambient PM2.5 concentration. An alternative modeling approach is explored based on estimation of near-road PM2.5 concentration and an in-vehicle mass balance. Near-road PM2.5 concentration is estimated using a dispersion model and fixed site monitor (FSM) data. In-vehicle concentration is estimated based on air exchange rate and filter efficiency. In-vehicle concentration varies with road type, traffic flow, windspeed, stability class, and ventilation. Average in-vehicle exposure is estimated to contribute 10 to 20 percent of average daily exposure. The contribution of in-vehicle exposure to total daily exposure can be higher for some individuals. Recommendations are made for updating exposure models and implementation of the alternative approach. PMID:23101000
A game of Chinese whispers in Malaysia: contextual analysis of child road safety education.
Puvanachandra, Prasanthi; Kulanthayan, Subramaniam; Hyder, Adnan A
2012-11-01
In 2006, the Malaysian government began implementing road safety education (RSE) programs in primary schools, involving numerous stakeholders. We interviewed 19 stakeholders. Thematic analysis led to the identification of four themes: road traffic injuries (RTIs) among children in Malaysia, the role of RSE, factors affecting successful implementation, and intersectoral involvement. The latter was identified as a significant strength of the overall approach to implementation, and is one of the first examples in Malaysia and in the region of such an approach. Lack of official documentation surrounding ownership, funding responsibilities, and roles among the various sectors led to resistance from some groups. Although we know from scientific studies what works in terms of reducing RTIs, the more important question is how such interventions can be successfully and sustainably implemented, particularly in low- and middle-income countries (LMIC). The results of this study permit stronger understanding of issues surrounding the implementation of RTI interventions in LMIC.
Wang, Tao; Zheng, Nanning; Xin, Jingmin; Ma, Zheng
2011-01-01
This paper presents a systematic scheme for fusing millimeter wave (MMW) radar and a monocular vision sensor for on-road obstacle detection. As a whole, a three-level fusion strategy based on visual attention mechanism and driver’s visual consciousness is provided for MMW radar and monocular vision fusion so as to obtain better comprehensive performance. Then an experimental method for radar-vision point alignment for easy operation with no reflection intensity of radar and special tool requirements is put forward. Furthermore, a region searching approach for potential target detection is derived in order to decrease the image processing time. An adaptive thresholding algorithm based on a new understanding of shadows in the image is adopted for obstacle detection, and edge detection is used to assist in determining the boundary of obstacles. The proposed fusion approach is verified through real experimental examples of on-road vehicle/pedestrian detection. In the end, the experimental results show that the proposed method is simple and feasible. PMID:22164117
Wang, Tao; Zheng, Nanning; Xin, Jingmin; Ma, Zheng
2011-01-01
This paper presents a systematic scheme for fusing millimeter wave (MMW) radar and a monocular vision sensor for on-road obstacle detection. As a whole, a three-level fusion strategy based on visual attention mechanism and driver's visual consciousness is provided for MMW radar and monocular vision fusion so as to obtain better comprehensive performance. Then an experimental method for radar-vision point alignment for easy operation with no reflection intensity of radar and special tool requirements is put forward. Furthermore, a region searching approach for potential target detection is derived in order to decrease the image processing time. An adaptive thresholding algorithm based on a new understanding of shadows in the image is adopted for obstacle detection, and edge detection is used to assist in determining the boundary of obstacles. The proposed fusion approach is verified through real experimental examples of on-road vehicle/pedestrian detection. In the end, the experimental results show that the proposed method is simple and feasible.
NASA Astrophysics Data System (ADS)
Chistyy, Y.; Kuzakhmetova, E.; Fazilova, Z.; Tsukanova, O.
2018-03-01
Design issues of junction of bridges and overhead road with approach embankment are studied. The reasons for the formation of deformations in the road structure are indicated. Activities to ensure sustainability and acceleration of the shrinkage of a weak subgrade approach embankment are listed. The necessity of taking into account the man-made impact of the approach embankment on the subgrade behavior is proved. Modern stabilizing agents to improve the properties of used soils in the embankment and the subgrade are suggested. Clarified methodology for determining an active zone of compression in the subgrade under load from the weight of the embankment is described. As an additional condition to the existing methodology for establishing the lower bound of the active zone of compression it is offered to accept the accuracy of evaluation of soil compressibility and determine shrinkage.
[Health risk assessment of traffic-related air pollution near busy roads].
Host, S; Chatignoux, E; Leal, C; Grémy, I
2012-08-01
Although ambient urban air pollution has well-established health effects, epidemiology faces many difficulties in estimating the risks due to exposure to traffic pollutants near busy roads. This review aims to summarize how exposure to traffic-related air pollution near busy roads is assessed in epidemiological studies and main findings regarding health effects. After presenting the specificity of emissions due to traffic road, this review identifies the key methods and main results found in epidemiologic studies seeking to measure the influence of exposure to nearby traffic on health published over the past decade. The characterization and measurement of population exposure to traffic pollution faces many difficulties. Thus, epidemiological studies have used two broad categories of surrogates to assess exposure: direct measures of traffic itself such as distance of the residence to the nearest road and traffic volume and modeled concentrations of pollutant surrogates. Studies that implemented these methods showed that people living near heavy traffic road or exposed to near-road air pollution tend to report more health outcomes. Traffic-related air pollution near busy roads is the subject of increasing attention, and tends to be better characterized. However, its health impacts remain difficult to grasp, especially because of the vast diversity of approaches used in epidemiological studies. Greater consistency in the protocols would be desirable to provide better understanding of the health issue of traffic in urban areas and thus to better implement policies to protect those most at risk. Copyright © 2012 Elsevier Masson SAS. All rights reserved.
Monitoring road safety development at regional level: A case study in the ASEAN region.
Chen, Faan; Wang, Jianjun; Wu, Jiaorong; Chen, Xiaohong; Zegras, P Christopher
2017-09-01
Persistent monitoring of progress, evaluating the results of interventions and recalibrating to achieve continuous improvement over time is widely recognized as being crucial towards the successful development of road safety. In the ASEAN (Association of Southeast Asian Nations) region there is a lack of well-resourced teams that contain multidisciplinary safety professionals, and specialists in individual countries, who are able to carry out this work effectively. In this context, not only must the monitoring framework be effective, it must also be easy to use and adapt. This paper provides a case study that can be easily reproduced; based on an updated and refined Road Safety Development Index (RSDI), by means of the RSR (Rank-sum ratio)-based model, for monitoring/reporting road safety development at regional level. The case study was focused on the road safety achievements in eleven Southeast Asian countries; identifying the areas of poor performance, potential problems and delays. These countries are finally grouped into several classes based on an overview of their progress and achievements regarding to road safety. The results allow the policymakers to better understand their own road safety progress toward their desired impact; more importantly, these results enable necessary interventions to be made in a quick and timely manner. Keeping action plans on schedule if things are not progressing as desired. This would avoid 'reinventing the wheel' and trial and error approaches to road safety, making the implementation of action plans more effective. Copyright © 2017 Elsevier Ltd. All rights reserved.
Callahan, J.E.; McIntyre, D.H.; Cooley, E.F.; Cookro, T.M.
1984-01-01
The Jerry Peak Wilderness Study Area is about 25 mi south of Challis in Custer County, central Idaho (fig. 1). The study area contains 46,150 acres of land administered by the by the Bureau of Land Management and 1 sq mi owned by the State of Idaho, a total of 46,790 acres. Most of the study area is readily accessible by roads along tributaries of the East Fork Salmon River, especially Road Creek, Herd Creek, and Lake Creek. The southeastern part of the area can be reached from Road Creek by the road down Peck's Canyon and by roads from Thousand Springs Valley, southeast of the study area. Several access roads to past logging operations extend up Sage Creek and its tributaries in the southeast part of the study area. Access to points within the northern part of the area is facilitated by jeep trails that connect with Road Creek and lake Creek and by improved road that extends northward from Herd Lake. The study area is moderately rugged, with local relief approaching 2,000 ft. Jerry (10,010 ft), the highest point within the area, is a low knoll on a north-trending linear ridge (fig. 1). The ridge has not been glaciated, despite its relatively high altitude. Most of the area is thinly covered by grass and low shrubs; trees, for the most part, are restricted to valley bottoms or to local, small groves on hillslopes.
Evaluation of Driver Visibility from Mobile LIDAR Data and Weather Conditions
NASA Astrophysics Data System (ADS)
González-Jorge, H.; Díaz-Vilariño, L.; Lorenzo, H.; Arias, P.
2016-06-01
Visibility of drivers is crucial to ensure road safety. Visibility is influenced by two main factors, the geometry of the road and the weather present therein. The present work depicts an approach for automatic visibility evaluation using mobile LiDAR data and climate information provided from weather stations located in the neighbourhood of the road. The methodology is based on a ray-tracing algorithm to detect occlusions from point clouds with the purpose of identifying the visibility area from each driver position. The resulting data are normalized with the climate information to provide a polyline with an accurate area of visibility. Visibility ranges from 25 m (heavy fog) to more than 10,000 m (clean atmosphere). Values over 250 m are not taken into account for road safety purposes, since this value corresponds to the maximum braking distance of a vehicle. Two case studies are evaluated an urban road in the city of Vigo (Spain) and an inter-urban road between the city of Ourense and the village of Castro Caldelas (Spain). In both cases, data from the Galician Weather Agency (Meteogalicia) are used. The algorithm shows promising results allowing the detection of particularly dangerous areas from the viewpoint of driver visibility. The mountain road between Ourense and Castro Caldelas, with great presence of slopes and sharp curves, shows special interest for this type of application. In this case, poor visibility can especially contribute to the run over of pedestrians or cyclists traveling on the road shoulders.
Morakinyo, Tobi Eniolu; Lam, Yun Fat; Hao, Song
2016-11-01
To enhance the quality of human life in a rapidly urbanized world plagued with high transportation, the masterful contribution of improved urban and local air quality cannot be overemphasized. In order to reduce human exposure to near-road air pollution, several approaches including the installation of roadside structural barriers especially in open street areas, such as city entrances are being applied. In the present study, the air quality around real world and idealized green infrastructures was investigated by means of numerical simulation and a short field measurement campaign. Fair agreement was found between ENVI-met modelled and measured particulate matter's concentration data around a realistic vegetation barrier indicating a fair representation of reality in the model. Several numerical experiments were conducted to investigate the influence of barrier type (vegetation/hedge and green wall) and dimensions on near-road air quality. The results show different horizontal/vertical patterns and magnitudes of upwind and downwind relative concentration (with and without a barrier) depending on wind condition, barrier type and dimension. Furthermore, an integrated dispersion-deposition approach was employed to assess the impact on air quality of near-road vegetation barrier. At last, recommendations to city and urban planners on the implementation of roadside structural barriers were made. Copyright © 2016 Elsevier Ltd. All rights reserved.
Automatic 3D Extraction of Buildings, Vegetation and Roads from LIDAR Data
NASA Astrophysics Data System (ADS)
Bellakaout, A.; Cherkaoui, M.; Ettarid, M.; Touzani, A.
2016-06-01
Aerial topographic surveys using Light Detection and Ranging (LiDAR) technology collect dense and accurate information from the surface or terrain; it is becoming one of the important tools in the geosciences for studying objects and earth surface. Classification of Lidar data for extracting ground, vegetation, and buildings is a very important step needed in numerous applications such as 3D city modelling, extraction of different derived data for geographical information systems (GIS), mapping, navigation, etc... Regardless of what the scan data will be used for, an automatic process is greatly required to handle the large amount of data collected because the manual process is time consuming and very expensive. This paper is presenting an approach for automatic classification of aerial Lidar data into five groups of items: buildings, trees, roads, linear object and soil using single return Lidar and processing the point cloud without generating DEM. Topological relationship and height variation analysis is adopted to segment, preliminary, the entire point cloud preliminarily into upper and lower contours, uniform and non-uniform surface, non-uniform surfaces, linear objects, and others. This primary classification is used on the one hand to know the upper and lower part of each building in an urban scene, needed to model buildings façades; and on the other hand to extract point cloud of uniform surfaces which contain roofs, roads and ground used in the second phase of classification. A second algorithm is developed to segment the uniform surface into buildings roofs, roads and ground, the second phase of classification based on the topological relationship and height variation analysis, The proposed approach has been tested using two areas : the first is a housing complex and the second is a primary school. The proposed approach led to successful classification results of buildings, vegetation and road classes.
Grilo, Clara; Del Cerro, Irene; Centeno-Cuadros, Alejandro; Ramiro, Victor; Román, Jacinto; Molina-Vacas, Guillem; Fernández-Aguilar, Xavier; Rodríguez, Juan; Porto-Peter, Flávia; Fonseca, Carlos; Revilla, Eloy; Godoy, José A
2016-09-15
Roads are widely recognized to represent a barrier to individual movements and, conversely, verges can act as potential corridors for the dispersal of many small mammals. Both barrier and corridor effects should generate a clear spatial pattern in genetic structure. Nevertheless, the effect of roads on the genetic structure of small mammal populations still remains unclear. In this study, we examine the barrier effect that different road types (4-lane highway, 2-lane roads and single-lane unpaved roads) may have on the population genetic structure of three species differing in relevant life history traits: southern water vole Arvicola sapidus, the Mediterranean pine vole Microtus duodecimcostatus and the Algerian mouse Mus spretus. We also examine the corridor effect of highway verges on the Mediterranean pine vole and the Algerian mouse. We analysed the population structure through pairwise estimates of FST among subpopulations bisected by roads, identified genetic clusters through Bayesian assignment approaches, and used simple and partial Mantel tests to evaluate the relative barrier or corridor effect of roads. No strong evidences were found for an effect of roads on population structure of these three species. The barrier effect of roads seems to be site-specific and no corridor effect of verges was found for the pine vole and Algerian mouse populations. The lack of consistent results among species and for each road type lead us to believe that the ability of individual dispersers to use those crossing structures or the habitat quality in the highway verges may have a relatively higher influence on gene flow among populations than the presence of crossing structures per se. Further research should include microhabitat analysis and the estimates of species abundance to understand the mechanisms that underlie the genetic structure observed at some sites. Copyright © 2016 Elsevier B.V. All rights reserved.
An integrated material metabolism model for stocks of urban road system in Beijing, China.
Guo, Zhen; Hu, Dan; Zhang, Fuhua; Huang, Guolong; Xiao, Qiang
2014-02-01
Rapid urbanization has greatly altered the urban metabolism of material and energy. As a significant part of the infrastructure, urban roads are being rapidly developed worldwide. Quantitative analysis of metabolic processes on urban road systems, especially the scale, composition and spatial distribution of their stocks, could help to assess the resource appropriation and potential environmental impacts, as well as improve urban metabolism models. In this paper, an integrated model, which covered all types of roads, intersection structures and ancillary facilities, was built for calculating the material stocks of urban road systems. Based on a bottom-up method, the total stocks were disassembled into a number of stock parts rather than obtained by input-output data, which provided an approach promoting data availability and inner structure understanding. The combination with GIS enabled the model to tackle the complex structures of road networks and avoid double counting. In the case study of Beijing, the following results are shown: 1) The total stocks for the entire road system reached 159 million tons, of which nearly 80% was stored in roads, and 20% in ancillary facilities. 2) Macadam was the largest stock (111 million tons), while stone mastic asphalt, polyurethane plastics, and atactic polypropylene accounted for smaller components of the overall system. 3) The stock per unit area of pedestrian overcrossing was higher than that of the other stock units in the entire system, and its steel stocks reached 0.49 t/m(2), which was 10 times as high as that in interchanges. 4) The high stock areas were mainly distributed in ring-shaped and radial expressways, as well as in major interchanges. 5) Expressways and arterials were excessively emphasized, while minor roads were relatively ignored. However, the variation of cross-sectional thickness in branches and neighborhood roads will have a significant impact on the scale of material stocks in the entire road system. © 2013.
Deck view, west approach; former Western Pacific (now Union Pacific) ...
Deck view, west approach; former Western Pacific (now Union Pacific) Railroad at left; wind turbine generators atop hill in background; view to northeast; 90mm lens - Carroll Overhead Bridge, Altamont Pass Road, Livermore, Alameda County, CA
Kalantari, Zahra; Briel, Annemarie; Lyon, Steve W; Olofsson, Bo; Folkeson, Lennart
2014-03-15
Road drainage structures are often designed using methods that do not consider process-based representations of a landscape's hydrological response. This may create inadequately sized structures as coupled land cover and climate changes can lead to an amplified hydrological response. This study aims to quantify potential increases of runoff in response to future extreme rain events in a 61 km(2) catchment (40% forested) in southwest Sweden using a physically-based hydrological modelling approach. We simulate peak discharge and water level (stage) at two types of pipe bridges and one culvert, both of which are commonly used at Swedish road/stream intersections, under combined forest clear-cutting and future climate scenarios for 2050 and 2100. The frequency of changes in peak flow and water level varies with time (seasonality) and storm size. These changes indicate that the magnitude of peak flow and the runoff response are highly correlated to season rather than storm size. In all scenarios considered, the dimensions of the current culvert are insufficient to handle the increase in water level estimated using a physically-based modelling approach. It also appears that the water level at the pipe bridges changes differently depending on the size and timing of the storm events. The findings of the present study and the approach put forward should be considered when planning investigations on and maintenance for areas at risk of high water flows. In addition, the research highlights the utility of physically-based hydrological models to identify the appropriateness of road drainage structure dimensioning. Copyright © 2014 Elsevier B.V. All rights reserved.
A Fuel-Based Assessment of On-Road and Off-Road Mobile Source Emission Trends
NASA Astrophysics Data System (ADS)
Dallmann, T. R.; Harley, R. A.
2009-12-01
Mobile sources contribute significantly to emissions of nitrogen oxides (NOx) and fine particulate matter (PM2.5) in the United States. These emissions lead to a variety of environmental concerns including adverse human health effects and climate change. In the electric power sector, sulfur dioxide (SO2) and NOx emissions from power plants are measured directly using continuous emission monitoring systems. In contrast for mobile sources, statistical models are used to estimate average emissions from a very large and diverse population of engines. Despite much effort aimed at improving them, mobile source emission inventories continue to have large associated uncertainties. Alternate methods are needed to help evaluate estimates of mobile source emissions and quantify and reduce the associated uncertainties. In this study, a fuel-based approach is used to estimate emissions from mobile sources, including on-road and off-road gasoline and diesel engines. In this approach, engine activity is measured by fuel consumed (in contrast EPA mobile source emission models are based on vehicle km of travel and total amount of engine work output for on-road and off-road engines, respectively). Fuel consumption is defined in this study based on highway fuel tax reports for on-road engines, and from surveys of fuel wholesalers who sell tax-exempt diesel fuel for use in various off-road sectors such as agriculture, construction, and mining. Over the decade-long time period (1996-2006) that is the focus of the present study, national sales of taxable gasoline and diesel fuel intended for on-road use increased by 15 and 43%, respectively. Diesel fuel use by off-road equipment increased by about 20% over the same time period. Growth in fuel consumption offset some of the reductions in pollutant emission factors that occurred during this period. This study relies on in-use measurements of mobile source emission factors, for example from roadside and tunnel studies, remote sensing, and plume capture experiments. Extensive in-use emissions data are available for NOx, especially for on-road engines. Measurements of exhaust PM2.5 emission factors are sparse in comparison. For NOx, there have been dramatic (factor of 2) decreases in emission factors for on-road gasoline engines between 1996 and 2006, due to use of improved catalytic converters on most engines. In contrast, diesel NOx emission factors decreased more gradually over the same time period. Exhaust PM2.5 emission factors appear to have decreased for most engine categories, but emission uncertainties are large for this pollutant. Pollutant emissions were estimated by combining fuel sales with emission factors expressed per unit of fuel burned. Diesel engines are the dominant mobile source of both NOx and PM2.5; the diesel contribution to NOx has increased over time as gasoline engine emissions have declined. Comparing fuel-based emission estimates with EPA’s national emission inventory led to the following conclusions: (1) total emissions of both NOx and PM2.5 estimated by two different methods were similar, (2) the distribution of source contributions to these totals differ significantly, with higher relative contributions coming from on-road diesel engines in this study compared to EPA.
Determinant of Road Traffic Crash Fatalities in Iran: A Longitudinal Econometric Analysis.
Rezaei, Satar; Bagheri Lankarani, Kamran; Karami Matin, Behzad; Bazyar, Mohammad; Hamzeh, Behrooz; Najafi, Farid
2015-01-01
Injuries and deaths from road traffic crashes are one of the main public health problems throughout the world. This study aimed to identify determinants of fatality traffic accident in Iran for the twenty-span year from 1991 to 2011. A time series analysis (1991-2011) was used to examine the effects of some of the key explanatory factors (GDP per capita, number of doctors per 10,000 populations, degree of urbanization, unemployment rate and motorization rate) on deaths from road traffic in Iran. In order to examine long- and short-run effects of variables, we employed autoregressive distributed lag (ARDL) approach and error correction method (ECM). The data for the study was obtained from the Central Bank of Iran (CBI), Iranian Statistical Center (ISC) and Legal medical organizations (LMO). GDP per capita, doctor per 10,000 populations, degree of urbanization and motorization rate had a significant impact on fatality from road traffic in Iran. We did not observe any short- and long-term effects of the unemployment rate on fatality from road traffic. GDP per capita, doctor per 10,000 populations, degree of urbanization and motorization rate were identified as main determinant of fatality from road traffic accidents in Iran. We hope the results of the current study enable health policy-makers to understand better the factors affecting deaths from road traffic accidents in the country.
Comparison of Point Matching Techniques for Road Network Matching
NASA Astrophysics Data System (ADS)
Hackeloeer, A.; Klasing, K.; Krisp, J. M.; Meng, L.
2013-05-01
Map conflation investigates the unique identification of geographical entities across different maps depicting the same geographic region. It involves a matching process which aims to find commonalities between geographic features. A specific subdomain of conflation called Road Network Matching establishes correspondences between road networks of different maps on multiple layers of abstraction, ranging from elementary point locations to high-level structures such as road segments or even subgraphs derived from the induced graph of a road network. The process of identifying points located on different maps by means of geometrical, topological and semantical information is called point matching. This paper provides an overview of various techniques for point matching, which is a fundamental requirement for subsequent matching steps focusing on complex high-level entities in geospatial networks. Common point matching approaches as well as certain combinations of these are described, classified and evaluated. Furthermore, a novel similarity metric called the Exact Angular Index is introduced, which considers both topological and geometrical aspects. The results offer a basis for further research on a bottom-up matching process for complex map features, which must rely upon findings derived from suitable point matching algorithms. In the context of Road Network Matching, reliable point matches provide an immediate starting point for finding matches between line segments describing the geometry and topology of road networks, which may in turn be used for performing a structural high-level matching on the network level.
Davis, Brett; Birch, Gavin
2010-08-01
Trace metal export by stormwater runoff from a major road and local street in urban Sydney, Australia, is compared using pollutant yield rating curves derived from intensive sampling data. The event loads of copper, lead and zinc are well approximated by logarithmic relationships with respect to total event discharge owing to the reliable appearance of a first flush in pollutant mass loading from urban roads. Comparisons of the yield rating curves for these three metals show that copper and zinc export rates from the local street are comparable with that of the major road, while lead export from the local street is much higher, despite a 45-fold difference in traffic volume. The yield rating curve approach allows problematic environmental data to be presented in a simple yet meaningful manner with less information loss. Copyright 2010 Elsevier Ltd. All rights reserved.
Promoting public health messages: Should we move beyond fear-evoking appeals in road safety?
Lewis, Ioni M; Watson, Barry; White, Katherine M; Tay, Richard
2007-01-01
Road traffic injury is one of the most significant global public health issues of the 21st century. The extent to which negative, fear-evoking messages represent effective persuasive strategies remains a contentious public and empirical issue. Nevertheless, negative, fear-based appeals represent a frequently used approach in Australasian road safety advertising. The authors conducted a series of focus groups with 16 licensed drivers to explore the potential utility of appeals to emotions other than fear. More specifically, they sought to explore the utility of positive emotional appeals, such as those incorporating humor. The themes emerging from the qualitative analysis suggested that both emotion and the provision of strategies are key components contributing to the overall persuasiveness of a road safety advertisement. Overall, it appears there is support for researchers and health advertising practitioners to provide further attention to the role that positive emotional appeals might play in future campaigns.
Fast and optimized methodology to generate road traffic emission inventories and their uncertainties
NASA Astrophysics Data System (ADS)
Blond, N.; Ho, B. Q.; Clappier, A.
2012-04-01
Road traffic emissions are one of the main sources of air pollution in the cities. They are also the main sources of uncertainties in the air quality numerical models used to forecast and define abatement strategies. Until now, the available models for generating road traffic emission always required a big effort, money and time. This inhibits decisions to preserve air quality, especially in developing countries where road traffic emissions are changing very fast. In this research, we developed a new model designed to fast produce road traffic emission inventories. This model, called EMISENS, combines the well-known top-down and bottom-up approaches to force them to be coherent. A Monte Carlo methodology is included for computing emission uncertainties and the uncertainty rate due to each input parameters. This paper presents the EMISENS model and a demonstration of its capabilities through an application over Strasbourg region (Alsace), France. Same input data as collected for Circul'air model (using bottom-up approach) which has been applied for many years to forecast and study air pollution by the Alsatian air quality agency, ASPA, are used to evaluate the impact of several simplifications that a user could operate . These experiments give the possibility to review older methodologies and evaluate EMISENS results when few input data are available to produce emission inventories, as in developing countries and assumptions need to be done. We show that same average fraction of mileage driven with a cold engine can be used for all the cells of the study domain and one emission factor could replace both cold and hot emission factors.
Speed cameras in Sweden and Victoria, Australia--a case study.
Belin, Matts-Ake; Tillgren, Per; Vedung, Evert; Cameron, Max; Tingvall, Claes
2010-11-01
In this article, the ideas behind two different speed camera systems in Australia, Victoria, and Sweden are explored and compared. The study shows that even if the both systems technically have the same aim--to reduce speeding--the ideas of how that should be achieved differ substantially. The approach adopted in Victoria is based on the concept that speeding is a deliberate offence in which a rational individual wants to drive as fast as possible and is prepared to calculate the costs and benefits of his behaviour. Therefore, the underlying aim of the intervention is to increase the perceived cost of committing an offence whilst at the same time decrease the perceived benefits, so that the former outweigh the latter. The Swedish approach, on the other hand, appears to be based on a belief that road safety is an important priority for the road users and one of the reasons to why road users drive too fast is lack of information and social support. In order to evaluate road safety interventions and how their effects are created together with the ambition to transfer technology, there is a need for a comprehensive understanding of the systems and their modi operandi in their specific contexts. This study has shown that there are major differences between the ideas behind the two speed camera programs in Victoria, Australia and Sweden and that these ideas have an impact on the actual design of the different systems and how these are intended to create road safety effects. 2010 Elsevier Ltd. All rights reserved.
Logistics Solution for Choosing Location of Production of Road Construction Enterprise
NASA Astrophysics Data System (ADS)
Gavrilina, I.; Bondar, A.
2017-11-01
The current state of construction of highways indicates that not all the resources of the construction organization are implemented and supported by the modern approaches in logistics problems solving. This article deals with the solution of these problems and considers the features of basic road linear works organization, their large extent and different locations of enterprises. Analyzing these data, it is proposed to simulate the logistics processes and substantiate the methods of transport operations organizing by linking the technology and the organization road construction materials delivery which allows one to optimize the construction processes, to choose the most economically advantageous options, and also to monitor the quality of work.
Road building, land use and climate change: prospects for environmental governance in the Amazon.
Perz, Stephen; Brilhante, Silvia; Brown, Foster; Caldas, Marcellus; Ikeda, Santos; Mendoza, Elsa; Overdevest, Christine; Reis, Vera; Reyes, Juan Fernando; Rojas, Daniel; Schmink, Marianne; Souza, Carlos; Walker, Robert
2008-05-27
Some coupled land-climate models predict a dieback of Amazon forest during the twenty-first century due to climate change, but human land use in the region has already reduced the forest cover. The causation behind land use is complex, and includes economic, institutional, political and demographic factors. Pre-eminent among these factors is road building, which facilitates human access to natural resources that beget forest fragmentation. While official government road projects have received considerable attention, unofficial road building by interest groups is expanding more rapidly, especially where official roads are being paved, yielding highly fragmented forest mosaics. Effective governance of natural resources in the Amazon requires a combination of state oversight and community participation in a 'hybrid' model of governance. The MAP Initiative in the southwestern Amazon provides an example of an innovative hybrid approach to environmental governance. It embodies a polycentric structure that includes government agencies, NGOs, universities and communities in a planning process that links scientific data to public deliberations in order to mitigate the effects of new infrastructure and climate change.
Parnell, Katie J; Stanton, Neville A; Plant, Katherine L
2017-03-01
Legislation in the road transport domain aims to control safety on the roads. Despite this, a critical issue affecting road safety is that of driver distraction. Although poorly defined, distraction is a significant road safety issue which, in part, is caused by the prevalence of technology within vehicles. Legislation surrounding the use of in-vehicle technologies are explored in this paper from a socio-technical system perspective. This reveals the wider context of the road transport system operating under the current laws using an Accimap analysis. A distinction in the law between the use of hand-held mobile phones, a device that is typically banned for use by drivers worldwide, and the use of other technological devices that are covered by more general laws against 'careless' and/or 'dangerous' driving was found. Historically, individual drivers' have been blamed for distraction, whereas the systems approach shows how current legislation may have created the conditions necessary for driver distraction. Copyright © 2016 Elsevier Ltd. All rights reserved.
Zhang, Lun; Zhang, Meng; Yang, Wenchen; Dong, Decun
2015-01-01
This paper presents the modelling and analysis of the capacity expansion of urban road traffic network (ICURTN). Thebilevel programming model is first employed to model the ICURTN, in which the utility of the entire network is maximized with the optimal utility of travelers' route choice. Then, an improved hybrid genetic algorithm integrated with golden ratio (HGAGR) is developed to enhance the local search of simple genetic algorithms, and the proposed capacity expansion model is solved by the combination of the HGAGR and the Frank-Wolfe algorithm. Taking the traditional one-way network and bidirectional network as the study case, three numerical calculations are conducted to validate the presented model and algorithm, and the primary influencing factors on extended capacity model are analyzed. The calculation results indicate that capacity expansion of road network is an effective measure to enlarge the capacity of urban road network, especially on the condition of limited construction budget; the average computation time of the HGAGR is 122 seconds, which meets the real-time demand in the evaluation of the road network capacity. PMID:25802512
2006-11-01
Avenue Urbana , IL 61801-4797 Final report Approved for public release; distribution is unlimited. Prepared for U.S. Army Corps of Engineers...allow validation of each structure’s effectiveness. Approach A research team consisting of members from the University of Illinois, Urbana ...and preferential drainage channel. Furthermore, dry weather conditions on unimproved ERDC/CERL TR-06-31 4 roads generate large volumes of airborne
2010-11-01
defined herein as terrain whose surface deformation due to a single vehicle traversing the surface is negligible, such as paved roads (both asphalt ...ground vehicle reliability predictions. Current application of this work is limited to the analysis of U.S. Highways, comprised of both asphalt and...Highways that are consistent between asphalt and concrete roads b. The principle terrain characteristics are defined with analytic basis vectors
Winter risk estimations through infrared cameras an principal component analysis
NASA Astrophysics Data System (ADS)
Marchetti, M.; Dumoulin, J.; Ibos, L.
2012-04-01
Thermal mapping has been implemented since the late eighties to measure road pavement temperature along with some other atmospheric parameters to establish a winter risk describing the susceptibility of road network to ice occurrence. Measurements are done using a vehicle circulating on the road network in various road weather conditions. When the dew point temperature drops below road surface temperature a risk of ice occurs and therefore a loss of grip risk for circulating vehicles. To avoid too much influence of the sun, and to see the thermal behavior of the pavement enhanced, thermal mapping is usually done before dawn during winter time. That is when the energy accumulated by the road during daytime is mainly dissipated (by radiation, by conduction and by convection) and before the road structure starts a new cycle. This analysis is mainly done when a new road network is built, or when some major pavement changes are made, or when modifications in the road surroundings took place that might affect the thermal heat balance. This helps road managers to install sensors to monitor road status on specific locations identified as dangerous, or simply to install specific road signs. Measurements are anyhow time-consuming. Indeed, a whole road network can hardly be analysed at once, and has to be partitioned in stretches that could be done in the open time window to avoid temperature artefacts due to a rising sun. The LRPC Nancy has been using a thermal mapping vehicle with now two infrared cameras. Road events were collected by the operator to help the analysis of the network thermal response. A conventional radiometer with appropriate performances was used as a reference. The objective of the work was to compare results from the radiometer and the cameras. All the atmospheric parameters measured by the different sensors such as air temperature and relative humidity were used as input parameters for the infrared camera when recording thermal images. Road thermal heterogeneities were clearly identified, while usually missed by a conventional radiometer. In the case presented here, the two lanes of the road could be properly observed. Promising perspectives appeared to increase the measurement rate. Furthermore, to cope with the climatic constraints of the winter measurements as to build a dynamic winter risk, a multivariate data analysis approach was implemented. Principal component analysis was performed and enabled to set up of dynamic thermal signature with a great agreement between statistical results and field measurements.
An Inquiry-Based Approach of Traditional "Step-by-Step" Experiments
ERIC Educational Resources Information Center
Szalay, L.; Tóth, Z.
2016-01-01
This is the start of a road map for the effective introduction of inquiry-based learning in chemistry. Advantages of inquiry-based approaches to the development of scientific literacy are widely discussed in the literature. However, unless chemistry educators take account of teachers' reservations and identified disadvantages such approaches will…
Crawford, Brian A.; Moore, Clinton; Norton, Terry M.; Maerz, John C.
2017-01-01
Roads represent a pervasive feature on most landscapes that can pose multiple threats to wildlife populations and substantial challenges for management. To be effective, management strategies must often target where threats are most concentrated. Road mortality and nest predation are well-documented threats to Diamond-backed Terrapins (Malaclemys terrapin) across the majority of their range, including the 8.7-km causeway to Jekyll Island, Georgia, USA, where both are predicted to contribute to population declines if left unmitigated. From 2009 to 2014, we used intensive road surveying to identify spatial peaks (hot spots) of terrapin crossing activity and road mortality and exploit these as targets for management. In 2011, we deployed a hybrid barrier composed of nest boxes, which were designed to prevent terrapins from accessing the road and mitigate nest predation, at one hot spot while leaving two other hot spots unmanaged. We evaluated the impact of the barrier on terrapin emergences on the causeway under a Before-After-Control-Impact (BACI) design, and a companion study evaluated the effects of nest boxes on nest predation rates. We estimated a 57% reduction in annual terrapin emergences at the barrier site compared to no measurable change at control hot spots. Our findings support the use of hybrid barriers for simultaneously addressing road mortality and nest predation for other terrapin populations at risk to these threats. Our approach highlights the need to design feasible but robust management strategies that target spatial peaks of road mortality while addressing additional threats contributing to population declines of terrapins and other species.
Anuran road-kills neighboring a peri-urban reserve in the Atlantic Forest, Brazil.
Coelho, Igor Pfeifer; Teixeira, Fernanda Zimmermann; Colombo, Patrick; Coelho, Artur Vicente Pfeifer; Kindel, Andreas
2012-12-15
Mortality from road-kills may figure among the important causes of decline in amphibian populations and species extinctions worldwide. Evaluation of the magnitude, composition, and temporal and spatial distributions of amphibian road-kills is a key step for mitigation planning, especially in peri-urban reserves. Once a month for 16 months, we surveyed, on foot, a 4.4 km section of state road ERS-389 bordering the Itapeva reserve in the southern Atlantic Forest. We recorded 1433 anuran road-kills and estimated a mortality rate of 9002 road-kills/km/year. The species most often recorded were the largest ones: Leptodactylus latrans, Rhinella icterica, Leptodactylus gracilis and Hypsiboas faber; 54.5% of the carcasses could not be identified. Anuran mortality was concentrated in summer, and was associated with temperature, rainfall and photoperiod. Leptodactylus road-kills were strongly influenced by vehicle traffic, probably because of its high abundance during the entire study period. Road-kill hotspots differed for anurans as a group and for single species, and we found an association among spatial patterns of mortality and types of land cover, distance from the nearest waterbody, roadside ditches, and artificial light. Traffic should be banned temporarily during periods of high mortality, which can be forecasted based on meteorological data. A comprehensive mitigation approach should take into account hotspots of all anuran records, and also of target species for selecting locations for amphibian passages and fencing. Roadside ditches, artificial waterbodies, and conventional street lights should be reduced as much as possible, since they may represent ecological traps for anuran populations. Copyright © 2012 Elsevier Ltd. All rights reserved.
Numerical investigation of road salt impact on an urban wellfield.
Bester, M L; Frind, E O; Molson, J W; Rudolph, D L
2006-01-01
The impact of road salt on a wellfield in a complex glacial moraine aquifer system is studied by numerical simulation. The moraine underlies an extensive urban and industrial landscape, which draws its water supply from >20 wellfields, several of which are approaching or have exceeded the drinking water limit for chloride. The study investigates the mechanisms of road salt infiltration, storage, and transport in the subsurface and assesses the effectiveness of mitigation measures designed to reduce the impact. The three-dimensional transport model accounts for increases in salt loading, as well as growth of the urbanized area and road network over the past 50 years. The simulations, which focus on one impacted wellfield, show chloride plumes originating mainly at arterial roads and migrating through aquitard windows into the water supply aquifers. The results suggest that the aquifer system contains a large and heterogeneously distributed mass of chloride and that concentrations in the aquifer can be substantially higher than the concentrations in the well water. Future impact scenarios indicate that although the system responds rapidly to reductions in salt loading, the residual chloride mass may take decades to flush out, even if road salting were discontinued. The implications with respect to urban wellfields in typical snow-belt areas are discussed.
Road traffic accidents prediction modelling: An analysis of Anambra State, Nigeria.
Ihueze, Chukwutoo C; Onwurah, Uchendu O
2018-03-01
One of the major problems in the world today is the rate of road traffic crashes and deaths on our roads. Majority of these deaths occur in low-and-middle income countries including Nigeria. This study analyzed road traffic crashes in Anambra State, Nigeria with the intention of developing accurate predictive models for forecasting crash frequency in the State using autoregressive integrated moving average (ARIMA) and autoregressive integrated moving average with explanatory variables (ARIMAX) modelling techniques. The result showed that ARIMAX model outperformed the ARIMA (1,1,1) model generated when their performances were compared using the lower Bayesian information criterion, mean absolute percentage error, root mean square error; and higher coefficient of determination (R-Squared) as accuracy measures. The findings of this study reveal that incorporating human, vehicle and environmental related factors in time series analysis of crash dataset produces a more robust predictive model than solely using aggregated crash count. This study contributes to the body of knowledge on road traffic safety and provides an approach to forecasting using many human, vehicle and environmental factors. The recommendations made in this study if applied will help in reducing the number of road traffic crashes in Nigeria. Copyright © 2017 Elsevier Ltd. All rights reserved.
Experimental Evaluation of Cement Replacement Fillers on the Performance of Slurry Seal
NASA Astrophysics Data System (ADS)
Fakhri, Mansour; Alrezaei, Hossein Ali; Naji Almasi, Soroush
2016-10-01
Reducing the level of roads service is a process that starts from the first day of the operation of road and the slope of deterioration curve of road sustainability becomes faster with the passage of time. After building the road, adopting an economic approach in order to maintain the road is very important. Slurry seal as one type of protective asphalts that works by sealing inactive cracks of the road and increasing skid resistance is the most effective types of restoration with environmentally friendly behaviour. Fillers are responsible for adjusting set time in slurry seal. Cement is the most common filler used in slurry seal. Cements having suitable properties as a filler, has a very energy demanding manufacturing process and a notable amount of energy is used for manufacturing cement in the country annually. On the other hand, manufacturing process and application of cement have increased levels of pollutant gases, followed by significant environmental pollution. So in this study other options as a filler such as hydrated lime, stone powder and the slag from iron melting furnace were compared with two common types of cement (Portland and type-v cement) in the mixtures of slurry seal by wet abrasion and cohesion tests. Results indicated that, in both tests, lime and slag fillers had behaviours close to the cement filler.
Staton, Catherine; Vissoci, Joao; Gong, Enying; Toomey, Nicole; Wafula, Rebeccah; Abdelgadir, Jihad; Zhou, Yi; Liu, Chen; Pei, Fengdi; Zick, Brittany; Ratliff, Camille D.; Rotich, Claire; Jadue, Nicole; de Andrade, Luciano; von Isenburg, Megan; Hocker, Michael
2016-01-01
Background Road traffic injuries (RTIs) are a growing but neglected global health crisis, requiring effective prevention to promote sustainable safety. Low- and middle-income countries (LMICs) share a disproportionately high burden with 90% of the world’s road traffic deaths, and where RTIs are escalating due to rapid urbanization and motorization. Although several studies have assessed the effectiveness of a specific intervention, no systematic reviews have been conducted summarizing the effectiveness of RTI prevention initiatives specifically performed in LMIC settings; this study will help fill this gap. Methods In accordance with PRISMA guidelines we searched the electronic databases MEDLINE, EMBASE, Scopus, Web of Science, TRID, Lilacs, Scielo and Global Health. Articles were eligible if they considered RTI prevention in LMICs by evaluating a prevention-related intervention with outcome measures of crash, RTI, or death. In addition, a reference and citation analysis was conducted as well as a data quality assessment. A qualitative metasummary approach was used for data analysis and effect sizes were calculated to quantify the magnitude of emerging themes. Results Of the 8560 articles from the literature search, 18 articles from 11 LMICs fit the eligibility and inclusion criteria. Of these studies, four were from Sub-Saharan Africa, ten from Latin America and the Caribbean, one from the Middle East, and three from Asia. Half of the studies focused specifically on legislation, while the others focused on speed control measures, educational interventions, enforcement, road improvement, community programs, or a multifaceted intervention. Conclusion Legislation was the most common intervention evaluated with the best outcomes when combined with strong enforcement initiatives or as part of a multifaceted approach. Because speed control is crucial to crash and injury prevention, road improvement interventions in LMIC settings should carefully consider how the impact of improvements will affect speed and traffic flow. Further road traffic injury prevention interventions should be performed in LMICs with patient-centered outcomes in order to guide injury prevention in these complex settings. PMID:26735918
NASA Astrophysics Data System (ADS)
Schmidt, Andres; Rella, Chris W.; Göckede, Mathias; Hanson, Chad; Yang, Zhenlin; Law, Beverly E.
2014-11-01
In recent years, measurements of atmospheric carbon dioxide with high precision and accuracy have become increasingly important for climate change research, in particular to inform terrestrial biosphere models. Anthropogenic carbon dioxide emissions from fossil fuel burning have long been recognized to contribute a significant portion of the carbon dioxide in the atmosphere. Here, we present an approach to remove the traffic related carbon dioxide emissions from mole fractions measured at a tall tower by using the corresponding carbon monoxide measurements in combination with footprint analyses and transport modeling. This technique improves the suitability of the CO2 data to be used in inverse modeling approaches of atmosphere-biosphere exchange that do not account for non-biotic portions of CO2. In our study region in Oregon, road traffic emissions are the biggest source of anthropogenic carbon dioxide and carbon monoxide. A three-day mobile campaign covering 1700 km of roads in northwestern Oregon was performed during summer of 2012 using a laser-based Cavity Ring-Down Spectrometer. The mobile measurements incorporated different roads including main highways, urban streets, and back-roads, largely within the typical footprint of a tall CO/CO2 observation tower in Oregon's Willamette Valley. For the first time, traffic related CO:CO2 emission ratios were measured directly at the sources during an on-road campaign under a variety of different driving conditions. An average emission ratio of 7.43 (±1.80) ppb CO per ppm CO2 was obtained for the study region and applied to separate the traffic related portion of CO2 from the mole fraction time series. The road traffic related portion of the CO2 mole fractions measured at the tower site reached maximum values ranging from 9.8 to 12 ppm, depending on the height above the surface, during summer 2012.
Responsible vendors, intelligent consumers: Silk Road, the online revolution in drug trading.
Van Hout, Marie Claire; Bingham, Tim
2014-03-01
Silk Road is located on the Deep Web and provides an anonymous transacting infrastructure for the retail of drugs and pharmaceuticals. Members are attracted to the site due to protection of identity by screen pseudonyms, variety and quality of product listings, selection of vendors based on reviews, reduced personal risks, stealth of product delivery, development of personal connections with vendors in stealth modes and forum activity. The study aimed to explore vendor accounts of Silk Road as retail infrastructure. A single and holistic case study with embedded units approach (Yin, 2003) was chosen to explore the accounts of vendor subunits situated within the Silk Road marketplace. Vendors (n=10) completed an online interview via the direct message facility and via Tor mail. Vendors described themselves as 'intelligent and responsible' consumers of drugs. Decisions to commence vending operations on the site centred on simplicity in setting up vendor accounts, and opportunity to operate within a low risk, high traffic, high mark-up, secure and anonymous Deep Web infrastructure. The embedded online culture of harm reduction ethos appealed to them in terms of the responsible vending and use of personally tested high quality products. The professional approach to running their Silk Road businesses and dedication to providing a quality service was characterised by professional advertising of quality products, professional communication and visibility on forum pages, speedy dispatch of slightly overweight products, competitive pricing, good stealth techniques and efforts to avoid customer disputes. Vendors appeared content with a fairly constant buyer demand and described a relatively competitive market between small and big time market players. Concerns were evident with regard to Bitcoin instability. The greatest threat to Silk Road and other sites operating on the Deep Web is not law enforcement or market dynamics, it is technology itself. Copyright © 2013 Elsevier B.V. All rights reserved.
An active structural acoustic control approach for the reduction of the structure-borne road noise
NASA Astrophysics Data System (ADS)
Douville, Hugo; Berry, Alain; Masson, Patrice
2002-11-01
The reduction of the structure-borne road noise generated inside the cabin of an automobile is investigated using an Active Structural Acoustic Control (ASAC) approach. First, a laboratory test bench consisting of a wheel/suspension/lower suspension A-arm assembly has been developed in order to identify the vibroacoustic transfer paths (up to 250 Hz) for realistic road noise excitation of the wheel. Frequency Response Function (FRF) measurements between the excitation/control actuators and each suspension/chassis linkage are used to characterize the different transfer paths that transmit energy through the chassis of the car. Second, a FE/BE model (Finite/Boundary Elements) was developed to simulate the acoustic field of an automobile cab interior. This model is used to predict the acoustic field inside the cabin as a response to the measured forces applied on the suspension/chassis linkages. Finally, an experimental implementation of ASAC is presented. The control approach relies on the use of inertial actuators to modify the vibration behavior of the suspension and the automotive chassis such that its noise radiation efficiency is decreased. The implemented algorithm consists of a MIMO (Multiple-Input-Multiple-Output) feedforward configuration with a filtered-X LMS algorithm using an advanced reference signal (width FIR filters) using the Simulink/Dspace environment for control prototyping.
Han, Zong-wei; Huang, Wei; Luo, Yun; Zhang, Chun-di; Qi, Da-cheng
2015-03-01
Taking the soil organic matter in eastern Zhongxiang County, Hubei Province, as a research object, thirteen sample sets from different regions were arranged surrounding the road network, the spatial configuration of which was optimized by the simulated annealing approach. The topographic factors of these thirteen sample sets, including slope, plane curvature, profile curvature, topographic wetness index, stream power index and sediment transport index, were extracted by the terrain analysis. Based on the results of optimization, a multiple linear regression model with topographic factors as independent variables was built. At the same time, a multilayer perception model on the basis of neural network approach was implemented. The comparison between these two models was carried out then. The results revealed that the proposed approach was practicable in optimizing soil sampling scheme. The optimal configuration was capable of gaining soil-landscape knowledge exactly, and the accuracy of optimal configuration was better than that of original samples. This study designed a sampling configuration to study the soil attribute distribution by referring to the spatial layout of road network, historical samples, and digital elevation data, which provided an effective means as well as a theoretical basis for determining the sampling configuration and displaying spatial distribution of soil organic matter with low cost and high efficiency.
12. View of Clark Fork Vehicle Bridge facing south. Approach ...
12. View of Clark Fork Vehicle Bridge facing south. Approach from the north road. Plaque was originally located where striped traffic sign is posted. - Clark Fork Vehicle Bridge, Spanning Clark Fork River, serves Highway 200, Clark Fork, Bonner County, ID
Air pollution and health risks due to vehicle traffic.
Zhang, Kai; Batterman, Stuart
2013-04-15
Traffic congestion increases vehicle emissions and degrades ambient air quality, and recent studies have shown excess morbidity and mortality for drivers, commuters and individuals living near major roadways. Presently, our understanding of the air pollution impacts from congestion on roads is very limited. This study demonstrates an approach to characterize risks of traffic for on- and near-road populations. Simulation modeling was used to estimate on- and near-road NO2 concentrations and health risks for freeway and arterial scenarios attributable to traffic for different traffic volumes during rush hour periods. The modeling used emission factors from two different models (Comprehensive Modal Emissions Model and Motor Vehicle Emissions Factor Model version 6.2), an empirical traffic speed-volume relationship, the California Line Source Dispersion Model, an empirical NO2-NOx relationship, estimated travel time changes during congestion, and concentration-response relationships from the literature, which give emergency doctor visits, hospital admissions and mortality attributed to NO2 exposure. An incremental analysis, which expresses the change in health risks for small increases in traffic volume, showed non-linear effects. For a freeway, "U" shaped trends of incremental risks were predicted for on-road populations, and incremental risks are flat at low traffic volumes for near-road populations. For an arterial road, incremental risks increased sharply for both on- and near-road populations as traffic increased. These patterns result from changes in emission factors, the NO2-NOx relationship, the travel delay for the on-road population, and the extended duration of rush hour for the near-road population. This study suggests that health risks from congestion are potentially significant, and that additional traffic can significantly increase risks, depending on the type of road and other factors. Further, evaluations of risk associated with congestion must consider travel time, the duration of rush-hour, congestion-specific emission estimates, and uncertainties. Copyright © 2013 Elsevier B.V. All rights reserved.
Air pollution and health risks due to vehicle traffic
Zhang, Kai; Batterman, Stuart
2014-01-01
Traffic congestion increases vehicle emissions and degrades ambient air quality, and recent studies have shown excess morbidity and mortality for drivers, commuters and individuals living near major roadways. Presently, our understanding of the air pollution impacts from congestion on roads is very limited. This study demonstrates an approach to characterize risks of traffic for on- and near-road populations. Simulation modeling was used to estimate on- and near-road NO2 concentrations and health risks for freeway and arterial scenarios attributable to traffic for different traffic volumes during rush hour periods. The modeling used emission factors from two different models (Comprehensive Modal Emissions Model and Motor Vehicle Emissions Factor Model version 6.2), an empirical traffic speed–volume relationship, the California Line Source Dispersion Model, an empirical NO2–NOx relationship, estimated travel time changes during congestion, and concentration–response relationships from the literature, which give emergency doctor visits, hospital admissions and mortality attributed to NO2 exposure. An incremental analysis, which expresses the change in health risks for small increases in traffic volume, showed non-linear effects. For a freeway, “U” shaped trends of incremental risks were predicted for on-road populations, and incremental risks are flat at low traffic volumes for near-road populations. For an arterial road, incremental risks increased sharply for both on- and near-road populations as traffic increased. These patterns result from changes in emission factors, the NO2–NOx relationship, the travel delay for the on-road population, and the extended duration of rush hour for the near-road population. This study suggests that health risks from congestion are potentially significant, and that additional traffic can significantly increase risks, depending on the type of road and other factors. Further, evaluations of risk associated with congestion must consider travel time, the duration of rush-hour, congestion-specific emission estimates, and uncertainties. PMID:23500830
Abdul Manan, Muhammad Marizwan
2014-09-01
This paper uses data from an observational study, conducted at access points in straight sections of primary roads in Malaysia in 2012, to investigate the effects of motorcyclists' behavior and road environment attributes on the occurrence of serious traffic conflicts involving motorcyclists entering primary roads via access points. In order to handle the unobserved heterogeneity in the small sample data size, this study applies mixed effects logistic regression with multilevel bootstrapping. Two statistically significant models (Model 2 and Model 3) are produced, with 2 levels of random effect parameters, i.e. motorcyclists' attributes and behavior at Level 1, and road environment attributes at Level 2. Among all the road environment attributes tested, the traffic volume and the speed limit are found to be statistically significant, only contributing to 26-29% of the variations affecting the traffic conflict outcome. The implication is that 71-74% of the unmeasured or undescribed attributes and behavior of motorcyclists still have an importance in predicting the outcome: a serious traffic conflict. As for the fixed effect parameters, both models show that the risk of motorcyclists being involved in a serious traffic conflict is 2-4 times more likely if they accept a shorter gap to a single approaching vehicle (time lag <4s) and in between two vehicles (time gap <4s) when entering the primary road from the access point. A road environment factor, such as a narrow lane (seen in Model 2), and a behavioral factor, such as stopping at the stop line (seen in Model 3), also influence the occurrence of a serious traffic conflict compared to those entering into a wider lane road and without stopping at the stop line, respectively. A discussion of the possible reasons for this seemingly strange result, including a recommendation for further research, concludes the paper. Copyright © 2014 Elsevier Ltd. All rights reserved.
Prediction of road accidents: A Bayesian hierarchical approach.
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 road network provided that the required data are available. Copyright © 2012 Elsevier Ltd. All rights reserved.
Vulnerability analysis methods for road networks
NASA Astrophysics Data System (ADS)
Bíl, Michal; Vodák, Rostislav; Kubeček, Jan; Rebok, Tomáš; Svoboda, Tomáš
2014-05-01
Road networks rank among the most important lifelines of modern society. They can be damaged by either random or intentional events. Roads are also often affected by natural hazards, the impacts of which are both direct and indirect. Whereas direct impacts (e.g. roads damaged by a landslide or due to flooding) are localized in close proximity to the natural hazard occurrence, the indirect impacts can entail widespread service disabilities and considerable travel delays. The change in flows in the network may affect the population living far from the places originally impacted by the natural disaster. These effects are primarily possible due to the intrinsic nature of this system. The consequences and extent of the indirect costs also depend on the set of road links which were damaged, because the road links differ in terms of their importance. The more robust (interconnected) the road network is, the less time is usually needed to secure the serviceability of an area hit by a disaster. These kinds of networks also demonstrate a higher degree of resilience. Evaluating road network structures is therefore essential in any type of vulnerability and resilience analysis. There are a range of approaches used for evaluation of the vulnerability of a network and for identification of the weakest road links. Only few of them are, however, capable of simulating the impacts of the simultaneous closure of numerous links, which often occurs during a disaster. The primary problem is that in the case of a disaster, which usually has a large regional extent, the road network may remain disconnected. The majority of the commonly used indices use direct computation of the shortest paths or time between OD (origin - destination) pairs and therefore cannot be applied when the network breaks up into two or more components. Since extensive break-ups often occur in cases of major disasters, it is important to study the network vulnerability in these cases as well, so that appropriate steps can be taken in order to make it more resilient. Performing such an analysis of network break-ups requires consideration of the network as a whole, ideally identifying all the cases generated by simultaneous closure of multiple links and evaluating them using various criteria. The spatial distribution of settlements, important companies and the overall population in the nodes of the network are several factors, apart from the topology of the network which could be taken into account when computing vulnerability indices and identifying the weakest links and/or weakest link combinations. However, even for small networks (i.e., hundreds of nodes and links), the problem of break-up identification becomes extremely difficult to resolve. The naive approaches of the brute force examination consequently fail and more elaborated algorithms have to be applied. We address the problem of evaluating the vulnerability of road networks in our work by simulating the impacts of the simultaneous closure of multiple roads/links. We present an ongoing work on a sophisticated algorithm focused on the identification of network break-ups and evaluating them by various criteria.
Attitudinal segmentaion of drivers in Pakistan: The potential for effective road safety campaigns.
Batool, Zahara; Carsten, Oliver
2018-05-01
Deviant driving behaviors are considered as the main cause of Road Traffic Accidents in Pakistan. This research is founded on the premise that driving behaviors are mediated by attitudinal and motivational factors. It advocates that rather than simply aggregating drivers' responses or a-priori classification of them based on their personal characteristics, adoption of segmentation technique is more useful to look at multiple factors provoking aberrant driving behavior in combination and not just in isolation. For this, the study generated an Attitudinal Questionnaire, inspired by the Ajzen's Theory of Planned Behavior (TPB: Ajzen, 1991), and extended violation-scale of modified Driver Behavior Questionnaire (DBQ: Lawton et al., 1997). Attitudinal and behavioral items are first factor analyzed. Then, cluster analysis is performed on extracted attitudinal factors which classified sample driving population into four relatively homogenous and distinct groups of drivers. The results demonstrated the explanatory utility of the market segmentation approach to systematically relate the interaction between attitudes, behaviors and socio-demographic characteristics of drivers. It is concluded that the approach is successful in distinguishing safe drivers from unsafe driver and therefore, can legitimately form the basis of road safety interventions. Finally, the findings are used to recommend targeted information-based road safety solutions with a focus on the diverse characteristics of each of the identified segments. Copyright © 2017 Elsevier Ltd. All rights reserved.
Measuring accident risk exposure for pedestrians in different micro-environments.
Lassarre, Sylvain; Papadimitriou, Eleonora; Yannis, George; Golias, John
2007-11-01
Pedestrians are mainly exposed to the risk of road accident when crossing a road in urban areas. Traditionally in the road safety field, the risk of accident for pedestrian is estimated as a rate of accident involvement per unit of time spent on the road network. The objective of this research is to develop an approach of accident risk based on the concept of risk exposure used in environmental epidemiology, such as in the case of exposure to pollutants. This type of indicator would be useful for comparing the effects of urban transportation policy scenarios on pedestrian safety. The first step is to create an indicator of pedestrians' exposure, which is based on motorised vehicles' "concentration" by lane and also takes account of traffic speed and time spent to cross. This is applied to two specific micro-environments: junctions and mid-block locations. A model of pedestrians' crossing behaviour along a trip is then developed, based on a hierarchical choice between junctions and mid-block locations and taking account of origin and destination, traffic characteristics and pedestrian facilities. Finally, a complete framework is produced for modelling pedestrians' exposure in the light of their crossing behaviour. The feasibility of this approach is demonstrated on an artificial network and a first set of results is obtained from the validation of the models in observational studies.
Mutation detection for inventories of traffic signs from street-level panoramic images
NASA Astrophysics Data System (ADS)
Hazelhoff, Lykele; Creusen, Ivo; De With, Peter H. N.
2014-03-01
Road safety is positively influenced by both adequate placement and optimal visibility of traffic signs. As their visibility degrades over time due to e.g. aging, vandalism, accidents and vegetation coverage, up-to-date inventories of traffic signs are highly attractive for preserving a high road safety. These inventories are performed in a semi-automatic fashion from street-level panoramic images, exploiting object detection and classification techniques. Next to performing inventories from scratch, these systems are also exploited for the efficient retrieval of situation changes by comparing the outcome of the automated system to a baseline inventory (e.g. performed in a previous year). This allows for specific manual interactions to the found changes, while skipping all unchanged situations, thereby resulting in a large efficiency gain. This work describes such a mutation detection approach, with special attention to re-identifying previously found signs. Preliminary results on a geographical area containing about 425 km of road show that 91.3% of the unchanged signs are re-identified, while the amount of found differences equals about 35% of the number of baseline signs. From these differences, about 50% correspond to physically changed traffic signs, next to false detections, misclassifications and missed signs. As a bonus, our approach directly results in the changed situations, which is beneficial for road sign maintenance.
Yadav, Santosh Kumar; Shrestha, Suraksha
2017-01-01
Patients are usually left in a vulnerable state after an accident. Because of this, they long for a good encounter when they are brought to the hospital. Physical impairment and psychological morbidities are some of the complications that can occur to them. Traditionally, surgeons tend to pay little attention to a patient's emotional and psychological perspective. The aim of this study was to understand the experience of oral and maxillofacial trauma patients due to road traffic accident right from immediate after the accident till the end of definitive treatment. Phenomenological approach of qualitative study was used to explore these patients' experience. Twenty subjects involved in road traffic accidents without any cognitive impairment aged 18 and above were recruited. Purposive sampling was used to include maximal variation sample regarding age, gender, types of injury, and types of treatment received. Semi-structured and open-ended interview approach was used to obtain in-depth information. Seven themes were identified to describe the patients' response to and experience after meeting with a road traffic accident; they are unreal experiences, emotional responses, need to inform and need for information, need for assistance, their perception toward the maxillofacial injury, their experience on treatment and staff-patient interaction. This qualitative study has provided an in-depth understanding of patients experience during maxillofacial trauma and treatment, which otherwise cannot be obtained by the use of surveys and test questions.
Road safety and road traffic accidents in Saudi Arabia. A systematic review of existing evidence.
Mansuri, Farah A; Al-Zalabani, Abdulmohsen H; Zalat, Marwa M; Qabshawi, Reem I
2015-04-01
To identify the changing trends and crucial preventive approaches to road traffic accidents (RTAs) adopted in the Kingdom of Saudi Arabia (KSA) over the last 2.5 decades, and to analyze aspects previously overlooked. This systematic review was based on evidence of RTAs in KSA. All articles published during the last 25 years on road traffic accident in KSA were analyzed. This study was carried out from December 2013 to May 2014 in the Department of Family and Community Medicine, Taibah University, Al-Madinah Al-Munawwarah, KSA. Road traffic accidents accounted for 83.4% of all trauma admissions in 1984-1989, and no such overall trend was studied thereafter. The most frequently injured body regions as reported in the latest studies were head and neck, followed by upper and lower extremities, which was found to be opposite to that of the studies reported earlier. Hospital data showed an 8% non-significant increase in road accident mortalities in contrast to police records of a 27% significant reduction during the years 2005-2010. Excessive speeding was the most common cause reported in all recent and past studies. Disparity was common in the type of reporting of RTAs, outcome measures, and possible causes over a period of 2.5 decade. All research exclusively looked into the drivers' faults. A sentinel surveillance of road crashes should be kept in place in the secondary and tertiary care hospitals for all regions of KSA.
Road safety and road traffic accidents in Saudi Arabia
Mansuri, Farah A.; Al-Zalabani, Abdulmohsen H.; Zalat, Marwa M.; Qabshawi, Reem I.
2015-01-01
Objectives: To identify the changing trends and crucial preventive approaches to road traffic accidents (RTAs) adopted in the Kingdom of Saudi Arabia (KSA) over the last 2.5 decades, and to analyze aspects previously overlooked. Methods: This systematic review was based on evidence of RTAs in KSA. All articles published during the last 25 years on road traffic accident in KSA were analyzed. This study was carried out from December 2013 to May 2014 in the Department of Family and Community Medicine, Taibah University, Al-Madinah Al-Munawwarah, KSA. Results: Road traffic accidents accounted for 83.4% of all trauma admissions in 1984-1989, and no such overall trend was studied thereafter. The most frequently injured body regions as reported in the latest studies were head and neck, followed by upper and lower extremities, which was found to be opposite to that of the studies reported earlier. Hospital data showed an 8% non-significant increase in road accident mortalities in contrast to police records of a 27% significant reduction during the years 2005-2010. Excessive speeding was the most common cause reported in all recent and past studies. Conclusion: Disparity was common in the type of reporting of RTAs, outcome measures, and possible causes over a period of 2.5 decade. All research exclusively looked into the drivers’ faults. A sentinel surveillance of road crashes should be kept in place in the secondary and tertiary care hospitals for all regions of KSA. PMID:25828277
NASA Astrophysics Data System (ADS)
Gulliver, John; de Hoogh, Kees; Fecht, Daniela; Vienneau, Danielle; Briggs, David
2011-12-01
The development of geographical information system techniques has opened up a wide array of methods for air pollution exposure assessment. The extent to which these provide reliable estimates of air pollution concentrations is nevertheless not clearly established. Nor is it clear which methods or metrics should be preferred in epidemiological studies. This paper compares the performance of ten different methods and metrics in terms of their ability to predict mean annual PM 10 concentrations across 52 monitoring sites in London, UK. Metrics analysed include indicators (distance to nearest road, traffic volume on nearest road, heavy duty vehicle (HDV) volume on nearest road, road density within 150 m, traffic volume within 150 m and HDV volume within 150 m) and four modelling approaches: based on the nearest monitoring site, kriging, dispersion modelling and land use regression (LUR). Measures were computed in a GIS, and resulting metrics calibrated and validated against monitoring data using a form of grouped jack-knife analysis. The results show that PM 10 concentrations across London show little spatial variation. As a consequence, most methods can predict the average without serious bias. Few of the approaches, however, show good correlations with monitored PM 10 concentrations, and most predict no better than a simple classification based on site type. Only land use regression reaches acceptable levels of correlation ( R2 = 0.47), though this can be improved by also including information on site type. This might therefore be taken as a recommended approach in many studies, though care is needed in developing meaningful land use regression models, and like any method they need to be validated against local data before their application as part of epidemiological studies.
Azetsop, Jacquineau
2010-01-01
Road traffic injury and deaths (RTID) are an important public health problem in Kenya, primarily affecting uneducated and disenfranchised people from lower socioeconomic groups. Studies conducted by Kenyan experts from police reports and surveys have shown that pedestrian and driver behaviors are the most important proximal causes of crashes, signifying that the occurrence of crashes results directly from human action. However, behaviors and risk factors do not fully explain the magnitude of RTID neither does it account for socioeconomic gradient in RTID. Instead, a social justice approach to RTID highlights the need for emphasizing distal causal factors. They allow us to understand how social inequities determine risk for RTID. Hence, designing policies that focus on behaviors will simply mask the underlying systemic causes of this growing phenomenon. To eradicate the RTID and address the gradient, a broader policy framework that includes the social dimension of injury, a strong political will to address the underlying causes of RTID and an effective partnership with stakeholders needs to be developed. PMID:20664752
NASA Astrophysics Data System (ADS)
Seppke, Benjamin; Dreschler-Fischer, Leonie; Wilms, Christian
2016-08-01
The extraction of road signatures from remote sensing images as a promising indicator for urbanization is a classical segmentation problem. However, some segmentation algorithms often lead to non-sufficient results. One way to overcome this problem is the usage of superpixels, that represent a locally coherent cluster of connected pixels. Superpixels allow flexible, highly adaptive segmentation approaches due to the possibility of merging as well as splitting and form new basic image entities. On the other hand, superpixels require an appropriate representation containing all relevant information about topology and geometry to maximize their advantages.In this work, we present a combined geometric and topological representation based on a special graph representation, the so-called RS-graph. Moreover, we present the use of the RS-graph by means of a case study: the extraction of partially occluded road networks in rural areas from open source (spectral) remote sensing images by tracking. In addition, multiprocessing and GPU-based parallelization is used to speed up the construction of the representation and the application.
Analyzing pedestrian crash injury severity under different weather conditions.
Li, Duo; Ranjitkar, Prakash; Zhao, Yifei; Yi, Hui; Rashidi, Soroush
2017-05-19
Pedestrians are the most vulnerable road users due to the lack of mass, speed, and protection compared to other types of road users. Adverse weather conditions may reduce road friction and visibility and thus increase crash risk. There is limited evidence and considerable discrepancy with regard to impacts of weather conditions on injury severity in the literature. This article investigated factors affecting pedestrian injury severity level under different weather conditions based on a publicly available accident database in Great Britain. Accident data from Great Britain that are publicly available through the STATS19 database were analyzed. Factors associated with pedestrian, driver, and environment were investigated using a novel approach that combines a classification and regression tree with random forest approach. Significant severity predictors under fine weather conditions from the models included speed limits, pedestrian age, light conditions, and vehicle maneuver. Under adverse weather conditions, the significant predictors were pedestrian age, vehicle maneuver, and speed limit. Elderly pedestrians are associated with higher pedestrian injury severities. Higher speed limits increase pedestrian injury severity. Based on the research findings, recommendations are provided to improve pedestrian safety.
Detection and Classification of Motor Vehicle Noise in a Forested Landscape
NASA Astrophysics Data System (ADS)
Brown, Casey L.; Reed, Sarah E.; Dietz, Matthew S.; Fristrup, Kurt M.
2013-11-01
Noise emanating from human activity has become a common addition to natural soundscapes and has the potential to harm wildlife and erode human enjoyment of nature. In particular, motor vehicles traveling along roads and trails produce high levels of both chronic and intermittent noise, eliciting varied responses from a wide range of animal species. Anthropogenic noise is especially conspicuous in natural areas where ambient background sound levels are low. In this article, we present an acoustic method to detect and analyze motor vehicle noise. Our approach uses inexpensive consumer products to record sound, sound analysis software to automatically detect sound events within continuous recordings and measure their acoustic properties, and statistical classification methods to categorize sound events. We describe an application of this approach to detect motor vehicle noise on paved, gravel, and natural-surface roads, and off-road vehicle trails in 36 sites distributed throughout a national forest in the Sierra Nevada, CA, USA. These low-cost, unobtrusive methods can be used by scientists and managers to detect anthropogenic noise events for many potential applications, including ecological research, transportation and recreation planning, and natural resource management.
Bridge rail and approach railing for low-volume roads in Iowa : final report, March 2010.
DOT National Transportation Integrated Search
2010-03-01
Bridge rail and approach guardrails provide safety to drivers by shielding more hazardous objects and redirecting vehicles to the : roadway. However, guardrail can increase both the initial cost and maintenance cost of a bridge, while adding another ...
Ehlers, Ute Christine; Ryeng, Eirin Olaussen; McCormack, Edward; Khan, Faisal; Ehlers, Sören
2017-02-01
The safety effects of cooperative intelligent transport systems (C-ITS) are mostly unknown and associated with uncertainties, because these systems represent emerging technology. This study proposes a bowtie analysis as a conceptual framework for evaluating the safety effect of cooperative intelligent transport systems. These seek to prevent road traffic accidents or mitigate their consequences. Under the assumption of the potential occurrence of a particular single vehicle accident, three case studies demonstrate the application of the bowtie analysis approach in road traffic safety. The approach utilizes exemplary expert estimates and knowledge from literature on the probability of the occurrence of accident risk factors and of the success of safety measures. Fuzzy set theory is applied to handle uncertainty in expert knowledge. Based on this approach, a useful tool is developed to estimate the effects of safety-related cooperative intelligent transport systems in terms of the expected change in accident occurrence and consequence probability. Copyright © 2016 Elsevier Ltd. All rights reserved.
A bounding-based solution approach for the continuous arc covering problem
NASA Astrophysics Data System (ADS)
Wei, Ran; Murray, Alan T.; Batta, Rajan
2014-04-01
Road segments, telecommunication wiring, water and sewer pipelines, canals and the like are important features of the urban environment. They are often conceived of and represented as network-based arcs. As a result of the usefulness and significance of arc-based features, there is a need to site facilities along arcs to serve demand. Examples of such facilities include surveillance equipment, cellular towers, refueling centers and emergency response stations, with the intent of being economically efficient as well as providing good service along the arcs. While this amounts to a continuous location problem by nature, various discretizations are generally relied upon to solve such problems. The result is potential for representation errors that negatively impact analysis and decision making. This paper develops a solution approach for the continuous arc covering problem that theoretically eliminates representation errors. The developed approach is applied to optimally place acoustic sensors and cellular base stations along a road network. The results demonstrate the effectiveness of this approach for ameliorating any error and uncertainty in the modeling process.
A Tool for Modelling the Probability of Landslides Impacting Road Networks
NASA Astrophysics Data System (ADS)
Taylor, Faith E.; Santangelo, Michele; Marchesini, Ivan; Malamud, Bruce D.; Guzzetti, Fausto
2014-05-01
Triggers such as earthquakes or heavy rainfall can result in hundreds to thousands of landslides occurring across a region within a short space of time. These landslides can in turn result in blockages across the road network, impacting how people move about a region. Here, we show the development and application of a semi-stochastic model to simulate how landslides intersect with road networks during a triggered landslide event. This was performed by creating 'synthetic' triggered landslide inventory maps and overlaying these with a road network map to identify where road blockages occur. Our landslide-road model has been applied to two regions: (i) the Collazzone basin (79 km2) in Central Italy where 422 landslides were triggered by rapid snowmelt in January 1997, (ii) the Oat Mountain quadrangle (155 km2) in California, USA, where 1,350 landslides were triggered by the Northridge Earthquake (M = 6.7) in January 1994. For both regions, detailed landslide inventory maps for the triggered events were available, in addition to maps of landslide susceptibility and road networks of primary, secondary and tertiary roads. To create 'synthetic' landslide inventory maps, landslide areas (AL) were randomly selected from a three-parameter inverse gamma probability density function, consisting of a power law decay of about -2.4 for medium and large values of AL and an exponential rollover for small values of AL. The number of landslide areas selected was based on the observed density of landslides (number of landslides km-2) in the triggered event inventories. Landslide shapes were approximated as ellipses, where the ratio of the major and minor axes varies with AL. Landslides were then dropped over the region semi-stochastically, conditioned by a landslide susceptibility map, resulting in a synthetic landslide inventory map. The originally available landslide susceptibility maps did not take into account susceptibility changes in the immediate vicinity of roads, therefore our landslide susceptibility map was adjusted to further reduce the susceptibility near each road based on the road level (primary, secondary, tertiary). For each model run, we superimposed the spatial location of landslide drops with the road network, and recorded the number, size and location of road blockages recorded, along with landslides within 50 and 100 m of the different road levels. Network analysis tools available in GRASS GIS were also applied to measure the impact upon the road network in terms of connectivity. The model was performed 100 times in a Monte-Carlo simulation for each region. Initial results show reasonable agreement between model output and the observed landslide inventories in terms of the number of road blockages. In Collazzone (length of road network = 153 km, landslide density = 5.2 landslides km-2), the median number of modelled road blockages over 100 model runs was 5 (±2.5 standard deviation) compared to the mapped inventory observed number of 5 road blockages. In Northridge (length of road network = 780 km, landslide density = 8.7 landslides km-2), the median number of modelled road blockages over 100 model runs was 108 (±17.2 standard deviation) compared to the mapped inventory observed number of 48 road blockages. As we progress with model development, we believe this semi-stochastic modelling approach will potentially aid civil protection agencies to explore different scenarios of road network potential damage as the result of different magnitude landslide triggering event scenarios.
23 CFR 661.51 - Can IRRBP funds be used for the approach roadway to a bridge?
Code of Federal Regulations, 2011 CFR
2011-04-01
... bridge? 661.51 Section 661.51 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS INDIAN RESERVATION ROAD BRIDGE PROGRAM § 661.51 Can IRRBP funds be used for the approach roadway to a bridge? (a) Yes, costs associated with approach roadway work, as defined in...
Signs All Around Us: A Project Approach Unit for Kindergarten
ERIC Educational Resources Information Center
MacDonell, Colleen
2007-01-01
There is no better way to start young children on the road to research skills than through the project approach. Designed with the distinctive characteristics of early childhood in mind, this article talks about child-centered approach to learning that allows individuals to work at their level of skill, comfort, and interest. The project approach…
23 CFR 661.51 - Can IRRBP funds be used for the approach roadway to a bridge?
Code of Federal Regulations, 2010 CFR
2010-04-01
... bridge? 661.51 Section 661.51 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS INDIAN RESERVATION ROAD BRIDGE PROGRAM § 661.51 Can IRRBP funds be used for the approach roadway to a bridge? (a) Yes, costs associated with approach roadway work, as defined in...
State, Parameter, and Unknown Input Estimation Problems in Active Automotive Safety Applications
NASA Astrophysics Data System (ADS)
Phanomchoeng, Gridsada
A variety of driver assistance systems such as traction control, electronic stability control (ESC), rollover prevention and lane departure avoidance systems are being developed by automotive manufacturers to reduce driver burden, partially automate normal driving operations, and reduce accidents. The effectiveness of these driver assistance systems can be significant enhanced if the real-time values of several vehicle parameters and state variables, namely tire-road friction coefficient, slip angle, roll angle, and rollover index, can be known. Since there are no inexpensive sensors available to measure these variables, it is necessary to estimate them. However, due to the significant nonlinear dynamics in a vehicle, due to unknown and changing plant parameters, and due to the presence of unknown input disturbances, the design of estimation algorithms for this application is challenging. This dissertation develops a new approach to observer design for nonlinear systems in which the nonlinearity has a globally (or locally) bounded Jacobian. The developed approach utilizes a modified version of the mean value theorem to express the nonlinearity in the estimation error dynamics as a convex combination of known matrices with time varying coefficients. The observer gains are then obtained by solving linear matrix inequalities (LMIs). A number of illustrative examples are presented to show that the developed approach is less conservative and more useful than the standard Lipschitz assumption based nonlinear observer. The developed nonlinear observer is utilized for estimation of slip angle, longitudinal vehicle velocity, and vehicle roll angle. In order to predict and prevent vehicle rollovers in tripped situations, it is necessary to estimate the vertical tire forces in the presence of unknown road disturbance inputs. An approach to estimate unknown disturbance inputs in nonlinear systems using dynamic model inversion and a modified version of the mean value theorem is presented. The developed theory is used to estimate vertical tire forces and predict tripped rollovers in situations involving road bumps, potholes, and lateral unknown force inputs. To estimate the tire-road friction coefficients at each individual tire of the vehicle, algorithms to estimate longitudinal forces and slip ratios at each tire are proposed. Subsequently, tire-road friction coefficients are obtained using recursive least squares parameter estimators that exploit the relationship between longitudinal force and slip ratio at each tire. The developed approaches are evaluated through simulations with industry standard software, CARSIM, with experimental tests on a Volvo XC90 sport utility vehicle and with experimental tests on a 1/8th scaled vehicle. The simulation and experimental results show that the developed approaches can reliably estimate the vehicle parameters and state variables needed for effective ESC and rollover prevention applications.
NASA Astrophysics Data System (ADS)
Foumelis, Michael
2017-01-01
The applicability of the normalized difference water index (NDWI) to the delineation of dam failure-induced floods is demonstrated for the case of the Sparmos dam (Larissa, Central Greece). The approach followed was based on the differentiation of NDWI maps to accurately define the extent of the inundated area over different time spans using multimission Earth observation optical data. Besides using Landsat data, for which the index was initially designed, higher spatial resolution data from Sentinel-2 mission were also successfully exploited. A geospatial analysis approach was then introduced to rapidly identify potentially affected segments of the road network. This allowed for further correlation to actual damages in the following damage assessment and remediation activities. The proposed combination of geographic information systems and remote sensing techniques can be easily implemented by local authorities and civil protection agencies for mapping and monitoring flood events.
'Silk Road', the virtual drug marketplace: a single case study of user experiences.
Van Hout, Marie Claire; Bingham, Tim
2013-09-01
The online promotion of 'drug shopping' and user information networks is of increasing public health and law enforcement concern. An online drug marketplace called 'Silk Road' has been operating on the 'Deep Web' since February 2011 and was designed to revolutionise contemporary drug consumerism. A single case study approach explored a 'Silk Road' user's motives for online drug purchasing, experiences of accessing and using the website, drug information sourcing, decision making and purchasing, outcomes and settings for use, and perspectives around security. The participant was recruited following a lengthy relationship building phase on the 'Silk Road' chat forum. The male participant described his motives, experiences of purchasing processes and drugs used from 'Silk Road'. Consumer experiences on 'Silk Road' were described as 'euphoric' due to the wide choice of drugs available, relatively easy once navigating the Tor Browser (encryption software) and using 'Bitcoins' for transactions, and perceived as safer than negotiating illicit drug markets. Online researching of drug outcomes, particularly for new psychoactive substances was reported. Relationships between vendors and consumers were described as based on cyber levels of trust and professionalism, and supported by 'stealth modes', user feedback and resolution modes. The reality of his drug use was described as covert and solitary with psychonautic characteristics, which contrasted with his membership, participation and feelings of safety within the 'Silk Road' community. 'Silk Road' as online drug marketplace presents an interesting displacement away from 'traditional' online and street sources of drug supply. Member support and harm reduction ethos within this virtual community maximises consumer decision-making and positive drug experiences, and minimises potential harms and consumer perceived risks. Future research is necessary to explore experiences and backgrounds of other users. Copyright © 2013 Elsevier B.V. All rights reserved.
Safety analysis of urban arterials at the meso level.
Li, Jia; Wang, Xuesong
2017-11-01
Urban arterials form the main structure of street networks. They typically have multiple lanes, high traffic volume, and high crash frequency. Classical crash prediction models investigate the relationship between arterial characteristics and traffic safety by treating road segments and intersections as isolated units. This micro-level analysis does not work when examining urban arterial crashes because signal spacing is typically short for urban arterials, and there are interactions between intersections and road segments that classical models do not accommodate. Signal spacing also has safety effects on both intersections and road segments that classical models cannot fully account for because they allocate crashes separately to intersections and road segments. In addition, classical models do not consider the impact on arterial safety of the immediately surrounding street network pattern. This study proposes a new modeling methodology that will offer an integrated treatment of intersections and road segments by combining signalized intersections and their adjacent road segments into a single unit based on road geometric design characteristics and operational conditions. These are called meso-level units because they offer an analytical approach between micro and macro. The safety effects of signal spacing and street network pattern were estimated for this study based on 118 meso-level units obtained from 21 urban arterials in Shanghai, and were examined using CAR (conditional auto regressive) models that corrected for spatial correlation among the units within individual arterials. Results showed shorter arterial signal spacing was associated with higher total and PDO (property damage only) crashes, while arterials with a greater number of parallel roads were associated with lower total, PDO, and injury crashes. The findings from this study can be used in the traffic safety planning, design, and management of urban arterials. Copyright © 2017 Elsevier Ltd. All rights reserved.
Automatic Detection and Classification of Audio Events for Road Surveillance Applications.
Almaadeed, Noor; Asim, Muhammad; Al-Maadeed, Somaya; Bouridane, Ahmed; Beghdadi, Azeddine
2018-06-06
This work investigates the problem of detecting hazardous events on roads by designing an audio surveillance system that automatically detects perilous situations such as car crashes and tire skidding. In recent years, research has shown several visual surveillance systems that have been proposed for road monitoring to detect accidents with an aim to improve safety procedures in emergency cases. However, the visual information alone cannot detect certain events such as car crashes and tire skidding, especially under adverse and visually cluttered weather conditions such as snowfall, rain, and fog. Consequently, the incorporation of microphones and audio event detectors based on audio processing can significantly enhance the detection accuracy of such surveillance systems. This paper proposes to combine time-domain, frequency-domain, and joint time-frequency features extracted from a class of quadratic time-frequency distributions (QTFDs) to detect events on roads through audio analysis and processing. Experiments were carried out using a publicly available dataset. The experimental results conform the effectiveness of the proposed approach for detecting hazardous events on roads as demonstrated by 7% improvement of accuracy rate when compared against methods that use individual temporal and spectral features.
NASA Astrophysics Data System (ADS)
Salek, Mansour; Levison, Jana; Parker, Beth; Gharabaghi, Bahram
2018-06-01
Road salt is pervasively used throughout Canada and in other cold regions during winter. For cities relying exclusively on groundwater, it is important to plan and minimize the application of salt accordingly to mitigate the adverse effects of high chloride concentrations in water supply aquifers. The use of geospatial data (road network, land use, Quaternary and bedrock geology, average annual recharge, water-table depth, soil distribution, topography) in the DRASTIC methodology provides an efficient way of distinguishing salt-vulnerable areas associated with groundwater supply wells, to aid in the implementation of appropriate management practices for road salt application in urban areas. This research presents a GIS-based methodology to accomplish a vulnerability analysis for 12 municipal water supply wells within the City of Guelph, Ontario, Canada. The chloride application density (CAD) value at each supply well is calculated and related to the measured groundwater chloride concentrations and further combined with soil media and aquifer vadose- and saturated-zone properties used in DRASTIC. This combined approach, CAD-DRASTIC, is more accurate than existing groundwater vulnerability mapping methods and can be used by municipalities and other water managers to further improve groundwater protection related to road salt application.
Drivers’ Visual Behavior-Guided RRT Motion Planner for Autonomous On-Road Driving
Du, Mingbo; Mei, Tao; Liang, Huawei; Chen, Jiajia; Huang, Rulin; Zhao, Pan
2016-01-01
This paper describes a real-time motion planner based on the drivers’ visual behavior-guided rapidly exploring random tree (RRT) approach, which is applicable to on-road driving of autonomous vehicles. The primary novelty is in the use of the guidance of drivers’ visual search behavior in the framework of RRT motion planner. RRT is an incremental sampling-based method that is widely used to solve the robotic motion planning problems. However, RRT is often unreliable in a number of practical applications such as autonomous vehicles used for on-road driving because of the unnatural trajectory, useless sampling, and slow exploration. To address these problems, we present an interesting RRT algorithm that introduces an effective guided sampling strategy based on the drivers’ visual search behavior on road and a continuous-curvature smooth method based on B-spline. The proposed algorithm is implemented on a real autonomous vehicle and verified against several different traffic scenarios. A large number of the experimental results demonstrate that our algorithm is feasible and efficient for on-road autonomous driving. Furthermore, the comparative test and statistical analyses illustrate that its excellent performance is superior to other previous algorithms. PMID:26784203
Drivers' Visual Behavior-Guided RRT Motion Planner for Autonomous On-Road Driving.
Du, Mingbo; Mei, Tao; Liang, Huawei; Chen, Jiajia; Huang, Rulin; Zhao, Pan
2016-01-15
This paper describes a real-time motion planner based on the drivers' visual behavior-guided rapidly exploring random tree (RRT) approach, which is applicable to on-road driving of autonomous vehicles. The primary novelty is in the use of the guidance of drivers' visual search behavior in the framework of RRT motion planner. RRT is an incremental sampling-based method that is widely used to solve the robotic motion planning problems. However, RRT is often unreliable in a number of practical applications such as autonomous vehicles used for on-road driving because of the unnatural trajectory, useless sampling, and slow exploration. To address these problems, we present an interesting RRT algorithm that introduces an effective guided sampling strategy based on the drivers' visual search behavior on road and a continuous-curvature smooth method based on B-spline. The proposed algorithm is implemented on a real autonomous vehicle and verified against several different traffic scenarios. A large number of the experimental results demonstrate that our algorithm is feasible and efficient for on-road autonomous driving. Furthermore, the comparative test and statistical analyses illustrate that its excellent performance is superior to other previous algorithms.
Bus accident analysis of routes with/without bus priority.
Goh, Kelvin Chun Keong; Currie, Graham; Sarvi, Majid; Logan, David
2014-04-01
This paper summarises findings on road safety performance and bus-involved accidents in Melbourne along roads where bus priority measures had been applied. Results from an empirical analysis of the accident types revealed significant reduction in the proportion of accidents involving buses hitting stationary objects and vehicles, which suggests the effect of bus priority in addressing manoeuvrability issues for buses. A mixed-effects negative binomial (MENB) regression and back-propagation neural network (BPNN) modelling of bus accidents considering wider influences on accident rates at a route section level also revealed significant safety benefits when bus priority is provided. Sensitivity analyses done on the BPNN model showed general agreement in the predicted accident frequency between both models. The slightly better performance recorded by the MENB model results suggests merits in adopting a mixed effects modelling approach for accident count prediction in practice given its capability to account for unobserved location and time-specific factors. A major implication of this research is that bus priority in Melbourne's context acts to improve road safety and should be a major consideration for road management agencies when implementing bus priority and road schemes. Copyright © 2013 Elsevier Ltd. All rights reserved.
Defogging of road images using gain coefficient-based trilateral filter
NASA Astrophysics Data System (ADS)
Singh, Dilbag; Kumar, Vijay
2018-01-01
Poor weather conditions are responsible for most of the road accidents year in and year out. Poor weather conditions, such as fog, degrade the visibility of objects. Thus, it becomes difficult for drivers to identify the vehicles in a foggy environment. The dark channel prior (DCP)-based defogging techniques have been found to be an efficient way to remove fog from road images. However, it produces poor results when image objects are inherently similar to airlight and no shadow is cast on them. To eliminate this problem, a modified restoration model-based DCP is developed to remove the fog from road images. The transmission map is also refined by developing a gain coefficient-based trilateral filter. Thus, the proposed technique has an ability to remove fog from road images in an effective manner. The proposed technique is compared with seven well-known defogging techniques on two benchmark foggy images datasets and five real-time foggy images. The experimental results demonstrate that the proposed approach is able to remove the different types of fog from roadside images as well as significantly improve the image's visibility. It also reveals that the restored image has little or no artifacts.
Road Risk Modeling and Cloud-Aided Safety-Based Route Planning.
Li, Zhaojian; Kolmanovsky, Ilya; Atkins, Ella; Lu, Jianbo; Filev, Dimitar P; Michelini, John
2016-11-01
This paper presents a safety-based route planner that exploits vehicle-to-cloud-to-vehicle (V2C2V) connectivity. Time and road risk index (RRI) are considered as metrics to be balanced based on user preference. To evaluate road segment risk, a road and accident database from the highway safety information system is mined with a hybrid neural network model to predict RRI. Real-time factors such as time of day, day of the week, and weather are included as correction factors to the static RRI prediction. With real-time RRI and expected travel time, route planning is formulated as a multiobjective network flow problem and further reduced to a mixed-integer programming problem. A V2C2V implementation of our safety-based route planning approach is proposed to facilitate access to real-time information and computing resources. A real-world case study, route planning through the city of Columbus, Ohio, is presented. Several scenarios illustrate how the "best" route can be adjusted to favor time versus safety metrics.
Clock Drawing as a Screen for Impaired Driving in Aging and Dementia: Is It Worth the Time?
Manning, Kevin J.; Davis, Jennifer D.; Papandonatos, George D.; Ott, Brian R.
2014-01-01
Clock drawing is recommended by medical and transportation authorities as a screening test for unsafe drivers. The objective of the present study was to assess the usefulness of different clock drawing systems as screening measures of driving performance in 122 healthy and cognitively impaired older drivers. Clock drawing was measured using four different scoring systems. Driving outcomes included global ratings of safety and the error rate on a standardized on-road test. Findings revealed that clock drawing was significantly correlated with the driving score on the road test for each of the scoring systems. However, receiver operator curve analyses showed limited clinical utility for clock drawing as a screening instrument for impaired on-road driving performance with the area under the curve ranging from 0.53 to 0.61. Results from this study indicate that clock drawing has limited utility as a solitary screening measure of on-road driving, even when considering a variety of scoring approaches. PMID:24296110
Clock drawing as a screen for impaired driving in aging and dementia: is it worth the time?
Manning, Kevin J; Davis, Jennifer D; Papandonatos, George D; Ott, Brian R
2014-02-01
Clock drawing is recommended by medical and transportation authorities as a screening test for unsafe drivers. The objective of the present study was to assess the usefulness of different clock drawing systems as screening measures of driving performance in 122 healthy and cognitively impaired older drivers. Clock drawing was measured using four different scoring systems. Driving outcomes included global ratings of safety and the error rate on a standardized on-road test. Findings revealed that clock drawing was significantly correlated with the driving score on the road test for each of the scoring systems. However, receiver operator curve analyses showed limited clinical utility for clock drawing as a screening instrument for impaired on-road driving performance with the area under the curve ranging from 0.53 to 0.61. Results from this study indicate that clock drawing has limited utility as a solitary screening measure of on-road driving, even when considering a variety of scoring approaches.
Starke, Sandra D; Baber, Chris; Cooke, Neil J; Howes, Andrew
2017-05-01
Road traffic control rooms rely on human operators to monitor and interact with information presented on multiple displays. Past studies have found inconsistent use of available visual information sources in such settings across different domains. In this study, we aimed to broaden the understanding of observer behaviour in control rooms by analysing a case study in road traffic control. We conducted a field study in a live road traffic control room where five operators responded to incidents while wearing a mobile eye tracker. Using qualitative and quantitative approaches, we investigated the operators' workflow using ergonomics methods and quantified visual information sampling. We found that individuals showed differing preferences for viewing modalities and weighting of task components, with a strong coupling between eye and head movement. For the quantitative analysis of the eye tracking data, we propose a number of metrics which may prove useful to compare visual sampling behaviour across domains in future. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.
From the Road Sign to the Map: 3d Modeling in Support of the Urban and Rural Road Conditions
NASA Astrophysics Data System (ADS)
Palummo, A.
2017-05-01
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.
NASA Astrophysics Data System (ADS)
Taylor, Faith E.; Santangelo, Michele; Marchesini, Ivan; Malamud, Bruce D.
2013-04-01
During a landslide triggering event, the tens to thousands of landslides resulting from the trigger (e.g., earthquake, heavy rainfall) may block a number of sections of the road network, posing a risk to rescue efforts, logistics and accessibility to a region. Here, we present initial results from a semi-stochastic model we are developing to evaluate the probability of landslides intersecting a road network and the network-accessibility implications of this across a region. This was performed in the open source GRASS GIS software, where we took 'model' landslides and dropped them on a 79 km2 test area region in Collazzone, Umbria, Central Italy, with a given road network (major and minor roads, 404 km in length) and already determined landslide susceptibilities. Landslide areas (AL) were randomly selected from a three-parameter inverse gamma probability density function, consisting of a power-law decay of about -2.4 for medium and large values of AL and an exponential rollover for small values of AL; the rollover (maximum probability) occurs at about AL = 400 m.2 The number of landslide areas selected for each triggered event iteration was chosen to have an average density of 1 landslide km-2, i.e. 79 landslide areas chosen randomly for each iteration. Landslides were then 'dropped' over the region semi-stochastically: (i) random points were generated across the study region; (ii) based on the landslide susceptibility map, points were accepted/rejected based on the probability of a landslide occurring at that location. After a point was accepted, it was assigned a landslide area (AL) and length to width ratio. Landslide intersections with roads were then assessed and indices such as the location, number and size of road blockage recorded. The GRASS-GIS model was performed 1000 times in a Monte-Carlo type simulation. Initial results show that for a landslide triggering event of 1 landslide km-2 over a 79 km2 region with 404 km of road, the number of road blockages ranges from 6 to 17, resulting in one road blockage every 24-67 km of roads. The average length of road blocked was 33 m. As we progress with model development and more sophisticated network analysis, we believe this semi-stochastic modelling approach will aid civil protection agencies to get a rough idea for the probability of road network potential damage (road block number and extent) as the result of different magnitude landslide triggering event scenarios.
NASA Astrophysics Data System (ADS)
Gidaris, I.; Gori, A.; Panakkal, P.; Padgett, J.; Bedient, P. B.
2017-12-01
The record-breaking rainfall produced over the Houston region by Hurricane Harvey resulted in catastrophic and unprecedented impacts on the region's infrastructure. Notably, Houston's transportation network was crippled, with almost every major highway flooded during the five-day event. Entire neighborhoods and subdivisions were inundated, rendering them completely inaccessible to rescue crews and emergency services. Harvey has tragically highlighted the vulnerability of major thoroughfares, as well as neighborhood roads, to severe inundation during extreme precipitation events. Furthermore, it has emphasized the need for detailed accessibility characterization of road networks under extreme event scenarios in order to determine which areas of the city are most vulnerable. This analysis assesses and tracks the accessibility of Houston's major highways during Harvey's evolution by utilizing road flood/closure data from the Texas DOT. In the absence of flooded/closure data for local roads, a hybrid approach is adopted that utilizes a physics-based hydrologic model to produce high-resolution inundation estimates for selected urban watersheds in the Houston area. In particular, hydrologic output in the form of inundation depths is used to estimate the operability of local roads. Ultimately, integration of hydrologic-based estimation of road conditions with observed data from DOT supports a network accessibility analysis of selected urban neighborhoods. This accessibility analysis can identify operable routes for emergency response (rescue crews, medical services, etc.) during the storm event.
Guo, Qiang; Xu, Pengpeng; Pei, Xin; Wong, S C; Yao, Danya
2017-02-01
Pedestrian safety is increasingly recognized as a major public health concern. Extensive safety studies have been conducted to examine the influence of multiple variables on the occurrence of pedestrian-vehicle crashes. However, the explicit relationship between pedestrian safety and road network characteristics remains unknown. This study particularly focused on the role of different road network patterns on the occurrence of crashes involving pedestrians. A global integration index via space syntax was introduced to quantify the topological structures of road networks. The Bayesian Poisson-lognormal (PLN) models with conditional autoregressive (CAR) prior were then developed via three different proximity structures: contiguity, geometry-centroid distance, and road network connectivity. The models were also compared with the PLN counterpart without spatial correlation effects. The analysis was based on a comprehensive crash dataset from 131 selected traffic analysis zones in Hong Kong. The results indicated that higher global integration was associated with more pedestrian-vehicle crashes; the irregular pattern network was proved to be safest in terms of pedestrian crash occurrences, whereas the grid pattern was the least safe; the CAR model with a neighborhood structure based on road network connectivity was found to outperform in model goodness-of-fit, implying the importance of accurately accounting for spatial correlation when modeling spatially aggregated crash data. Copyright © 2016 Elsevier Ltd. All rights reserved.
[Evaluation on the effects of education regarding road safety among middle school students].
Jin, Hui-Qing; Li, Ying-Chun; Zhang, Shu-Lin; Yu, Wan-Sheng
2009-08-01
To evaluate the intervention effects for road traffic accident prevention among middle school students through understanding their knowledge, attitude and practice (KAP) on road safety. Students in Grade 1 and Grade 2 from 7 junior and senior middle schools in Ji'nan city were selected as intervention group and students from a middle school in Hefei city served as control group. Education was provided to the intervention group and all the middle school students in Ji'nan city. Changes of KAP on road safety were measured for both groups during the follow-up period, and comparison on KAP for the two groups was carried statistically. The mean scores of road safety knowledge for intervention group improved significantly during the follow-up period (from 0.9 - 3.8), while these indices did not change much in the control group (from 0 - 0.2). Negative attitude on road safety was found in both groups, but less in the intervention group. More students started to admit that middle school students themselves should be responsible for most of the RTAs. Per week frequency of violating traffic rules did not improve, however during the follow-up period on both groups as still 75% to 80% of the students violating the traffic rules less than 2 times per week. Although three kinds and one kind of traffic rules violation seemed to have improved in the intervention group and in the control group, there were still two and three other kinds turned worse in the intervention and in the control group, respectively. Program on road safety education significantly improved the relative knowledge for middle school student and it exerted positive effects in road safety attitude to some extent. However, no significant effect was found in the improvement on their behavior. Education on road safety should be carried out in the early stage of childhood with newer and more effective intervention approaches.
Fuller, Michael P.
2017-01-01
A total of 145007 reads were obtained from pyrosequencing for all the 4 samples. The total count ranged from 11,301,014 (Mecca old road) to 23,503,512 bp (Thuwal). A total of 460 fungal species belonging to 133 genera, 58 families, 33 orders, 13 classes and 4 phyla was identified across the four sites. The most abundant phylum at all four sites was Ascomycota followed by Basidiomycota. Four phyla (Ascomycota—99.31%, Basidiomycota—0.59%, Chytridiomycota—0.04%, Glomeromycota—0.03%) were detected in Khulais. Except for Glomeromycota, all phyla were detected at Mecca old road (Ascomycota—74.26%, Basidiomycota—25.71%, Chytridiomycota—0.01%) and Thuwal (Ascomycota—99.59%, Basidiomycota—0.40%, Chytridiomycota—0.002%); while only Ascomycota—90.98% and Basidiomycota—9.01% were detected in Asfan road. At the class level, Sordariomycetes was predominantly observed at Asfan road—59.88%, Khulais—68.26% and Thuwal—94.84%; while Pezizomycetes was dominant at Mecca old road—56.01%, was absent at Asfan road. Agaricomycetes was present only at Mecca old road—25.73%; while Tremellomycetes—5.77%, Malasseizomycetes—2.13% and Microbotryomycetes—1.10% were found only at Asfan road. The phylogenetic trees revealed that clear genus level differences are visible across all the four sites, with an overall predominance of Thielavia followed by Madurella, Aspergillus, and Gelasinospora. Chaetomium sp., Aspergillus caespitosus and Aspergillus sp. were found in moderate (Mecca old road and Thuwal) to abundant (Asfan road and Khulais) quantities. Thielavia sp., Thielavia hyalocarpa and Madurella sp. are found in moderate quantities at Khulais and Mecca old road, while in abundant levels at Asfan road and Thuwal. Fusarium equisati and F. oxysporum were detected at Thuwal and Khulais. Sordaria araneosa was present at Khulais, while Malasseiza globosa species was detected in moderate quantities across all sites except Khulais. PMID:28934322
The paper presents a hybrid air quality modeling approach and its application in NEXUS in order to provide spatial and temporally varying exposure estimates and identification of the mobile source contribution to the total pollutant exposure. Model-based exposure metrics, associa...
Nazif, José Ignacio
2011-01-01
Three theories offer different explanations to the understanding of male drink-driving. In order to test road safety education, deterrence, and social capital theories, logistic regression analysis was applied to predict respondents' statements of having or not having engaged in actual drink-driving (DD). Variable for road safety education theory was whether a driver had graduated from a professional driving school or not. Deterrence theory was operationalized with a variable of whether a driver had been issued a traffic ticket or not. Social capital theory was operationalized with two variables, having children or not and having religion identification or not. Since both variables 'years of formal education' and 'years of driving experience' have been reported to be correlated to alcohol consumption and DD respectively, these were introduced as controls. In order to assess the significance of each variable statistically, Wald tests were applied in seven models. Results indicate on the one hand that road safety education variable is not statistically significant; and on the other, deterrence theory variable and social capital theory variable 'having children' were both statistically significant at the level of .01. Findings are discussed in reference to Chile's context. Data were taken from the "Road Users Attitudes and Behaviors towards Traffic Safety" survey from the National Commission of Road Safety of the Government of Chile (2005). The sample size was reported to be 2,118 (N of male drivers was 396). This survey was representative of Chile's Metropolitan Region road users' population.
The implications of the relative risk for road mortality on road safety programmes in Qatar.
Consunji, Rafael J; Peralta, Ruben R; Al-Thani, Hassan; Latifi, Rifat
2015-04-01
The epidemiology of road deaths and in particular the relative risk for road mortality (RRRM) in Qatar has not been fully defined. This study will analyse and compare the proportionate mortality and age-specific death rates from road traffic injuries (RTIs) and make recommendations for targeted injury prevention programmes for road safety in Qatar. Data from the Qatar Statistics Authority (QSA), for the year 2010, was collected and analysed. All deaths classified as 'ICD-10 (V89) Motor- or Nonmotor-Vehicle, Accident Type of Vehicle Unspecified' were included. There were 247 RTI related deaths in Qatar in 2010. An overall death rate was computed at 14.4 deaths per 100 000 population. The RRRM varied over 10 times among different populations with Qatari males (QM) having an increased RRRM from 10 years of age, those aged 20-29 years had the highest RRRM of 10.2. The lowest RRRM was for Qatari females who did not have a single reported road fatality in 2010. Populations with a significantly elevated RRRM (ie, RRRM>1.0) were non-Qatari men older than 50 years and Qatari males from the age of 10 onward. Proven and definite programmes must be implemented to reduce these unnecessary deaths among the populations at the highest risk. Multidisciplinary approaches must be implemented and their efficacy evaluated. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Ramos-Scharrón, Carlos E; Figueroa-Sánchez, Yasiel
2017-11-01
The combination of a topographically abrupt wet-tropical setting with the high level of soil exposure that typifies many sun-grown coffee farms represents optimal conditions for high erosion rates. Although traditionally considered as a main cause for water resource degradation, limited empirical evidence has existed to document its true contribution. This study relies on plot-scale experimental results conducted in western Puerto Rico to assess the impact of cultivated surfaces and farm access roads on runoff and sediment production from the plot to the farm and watershed scales. Results show that unsurfaced and graveled road surfaces produce one- to two-orders of magnitude more per unit area runoff than cultivated lands. Similarly, erosion rates from unsurfaced roads are about 102 g m -2 per cm of rainfall and these are two-orders of magnitude greater than from actively cultivated surfaces. Mitigation practices such as uncompacting road surfaces by ripping and gravel application reduce onsite erosion rates to 0.6% and 8% of unsurfaced conditions, respectively. At the farm scale, coffee farms are estimated to produce sediment at a rate of 12-18 Mg ha -1 yr -1 , and roads are undoubtedly the dominant sediment source responsible for 59-95% of the total sediment produced. The costs associated to ameliorating erosion problems through road graveling are high. Therefore, a combined approach that treats road erosion onsite with one that traps sediment before it reaches river networks is the viable solution to this problem. Copyright © 2017 Elsevier Ltd. All rights reserved.
Modelling of road traffic fatalities in India.
Goel, Rahul
2018-03-01
Passenger modes in India include walking, cycling, buses, trains, intermediate public transport modes (IPT) such as three-wheeled auto rickshaws or tuk-tuks, motorised two-wheelers (2W) as well as cars. However, epidemiological studies of traffic crashes in India have been limited in their approach to account for the exposure of these road users. In 2011, for the first time, census in India reported travel distance and mode of travel for workers. A Poisson-lognormal mixture regression model is developed at the state level to explore the relationship of road deaths of all the road users with commute travel distance by different on-road modes. The model controlled for diesel consumption (proxy for freight traffic), length of national highways, proportion of population in urban areas, and built-up population density. The results show that walking, cycling and, interestingly, IPT are associated with lower risk of road deaths, while 2W, car and bus are associated with higher risk. Promotion of IPT has twofold benefits of increasing safety as well as providing a sustainable mode of transport. The mode shift scenarios show that, for similar mode shift across the states, the resulting trends in road deaths are highly dependent on the baseline mode shares. The most worrying trend is the steep growth of death burden resulting from mode shift of walking and cycling to 2W. While the paper illustrates a limited set of mode shift scenarios involving two modes at a time, the model can be applied to assess safety impacts resulting from a more complex set of scenarios. Copyright © 2018 The Author. Published by Elsevier Ltd.. All rights reserved.
Nazif, José Ignacio
2011-01-01
Three theories offer different explanations to the understanding of male drink-driving. In order to test road safety education, deterrence, and social capital theories, logistic regression analysis was applied to predict respondents’ statements of having or not having engaged in actual drink-driving (DD). Variable for road safety education theory was whether a driver had graduated from a professional driving school or not. Deterrence theory was operationalized with a variable of whether a driver had been issued a traffic ticket or not. Social capital theory was operationalized with two variables, having children or not and having religion identification or not. Since both variables ‘years of formal education’ and ‘years of driving experience’ have been reported to be correlated to alcohol consumption and DD respectively, these were introduced as controls. In order to assess the significance of each variable statistically, Wald tests were applied in seven models. Results indicate on the one hand that road safety education variable is not statistically significant; and on the other, deterrence theory variable and social capital theory variable ‘having children’ were both statistically significant at the level of .01. Findings are discussed in reference to Chile’s context. Data were taken from the “Road Users Attitudes and Behaviors towards Traffic Safety” survey from the National Commission of Road Safety of the Government of Chile (2005). The sample size was reported to be 2,118 (N of male drivers was 396). This survey was representative of Chile’s Metropolitan Region road users' population. PMID:22105406
Driving Behaviour Profile of Drivers with Autism Spectrum Disorder (ASD).
Chee, Derserri Y; Lee, Hoe C; Patomella, Ann-Helen; Falkmer, Torbjörn
2017-09-01
The symptomatology of autism spectrum disorder (ASD) can make driving risky, but little is known about the on-road driving behaviour of individuals with ASD. This study assessed and compared the on-road driving performance of drivers with and without ASD, and explored how the symptomatology of ASD hinders or facilitates on-road driving performance. Sixteen drivers with ASD and 21 typically-developed drivers participated in the study. Drivers with ASD underperformed in vehicle manoeuvring, especially at left-turns, right-turns and pedestrian crossings. However, drivers with ASD outperformed the TD group in aspects related to rule-following such as using the indicator at roundabouts and checking for cross-traffic when approaching intersections. Drivers with ASD in the current study presented with a range of capabilities and weaknesses during driving.
Guo, Yanyong; Li, Zhibin; Wu, Yao; Xu, Chengcheng
2018-06-01
Bicyclists running the red light at crossing facilities increase the potential of colliding with motor vehicles. Exploring the contributing factors could improve the prediction of running red-light probability and develop countermeasures to reduce such behaviors. However, individuals could have unobserved heterogeneities in running a red light, which make the accurate prediction more challenging. Traditional models assume that factor parameters are fixed and cannot capture the varying impacts on red-light running behaviors. In this study, we employed the full Bayesian random parameters logistic regression approach to account for the unobserved heterogeneous effects. Two types of crossing facilities were considered which were the signalized intersection crosswalks and the road segment crosswalks. Electric and conventional bikes were distinguished in the modeling. Data were collected from 16 crosswalks in urban area of Nanjing, China. Factors such as individual characteristics, road geometric design, environmental features, and traffic variables were examined. Model comparison indicates that the full Bayesian random parameters logistic regression approach is statistically superior to the standard logistic regression model. More red-light runners are predicted at signalized intersection crosswalks than at road segment crosswalks. Factors affecting red-light running behaviors are gender, age, bike type, road width, presence of raised median, separation width, signal type, green ratio, bike and vehicle volume, and average vehicle speed. Factors associated with the unobserved heterogeneity are gender, bike type, signal type, separation width, and bike volume. Copyright © 2018 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Zhang, Ying; Lantz, Nicholas; Guindon, Bert; Jiao, Xianfen
2017-01-01
Accurate and frequent monitoring of land surface changes arising from oil and gas exploration and extraction is a key requirement for the responsible and sustainable development of these resources. Petroleum deposits typically extend over large geographic regions but much of the infrastructure required for oil and gas recovery takes the form of numerous small-scale features (e.g., well sites, access roads, etc.) scattered over the landscape. Increasing exploitation of oil and gas deposits will increase the presence of these disturbances in heavily populated regions. An object-based approach is proposed to utilize RapidEye satellite imagery to delineate well sites and related access roads in diverse complex landscapes, where land surface changes also arise from other human activities, such as forest logging and agriculture. A simplified object-based change vector approach, adaptable to operational use, is introduced to identify the disturbances on land based on red-green spectral response and spatial attributes of candidate object size and proximity to roads. Testing of the techniques has been undertaken with RapidEye multitemporal imagery in two test sites located at Alberta, Canada: one was a predominant natural forest landscape and the other landscape dominated by intensive agricultural activities. Accuracies of 84% and 73%, respectively, have been achieved for the identification of well site and access road infrastructure of the two sites based on fully automated processing. Limited manual relabeling of selected image segments can improve these accuracies to 95%.
Stewart, Heather; Massoudieh, Arash; Gellis, Allen C.
2015-01-01
A Bayesian chemical mass balance (CMB) approach was used to assess the contribution of potential sources for fluvial samples from Laurel Hill Creek in southwest Pennsylvania. The Bayesian approach provides joint probability density functions of the sources' contributions considering the uncertainties due to source and fluvial sample heterogeneity and measurement error. Both elemental profiles of sources and fluvial samples and 13C and 15N isotopes were used for source apportionment. The sources considered include stream bank erosion, forest, roads and agriculture (pasture and cropland). Agriculture was found to have the largest contribution, followed by stream bank erosion. Also, road erosion was found to have a significant contribution in three of the samples collected during lower-intensity rain events. The source apportionment was performed with and without isotopes. The results were largely consistent; however, the use of isotopes was found to slightly increase the uncertainty in most of the cases. The correlation analysis between the contributions of sources shows strong correlations between stream bank and agriculture, whereas roads and forest seem to be less correlated to other sources. Thus, the method was better able to estimate road and forest contributions independently. The hypothesis that the contributions of sources are not seasonally changing was tested by assuming that all ten fluvial samples had the same source contributions. This hypothesis was rejected, demonstrating a significant seasonal variation in the sources of sediments in the stream.
The ecological impact assessment of a proposed road development (the Slovak approach)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Igondova, Erika, E-mail: erika.igondova@gmail.com; Pavlickova, Katarina, E-mail: pavlickova60@gmail.com; Majzlan, Oto, E-mail: majzlan@fns.uniba.sk
The construction of roads is one of the most widespread forms of natural landscape modification. Over the last 20 years, dozens of road constructions have been assessed in Slovakia, which makes it possible to talk about methodological positives and negatives. A special feature of Slovakia is that many planned or renovated roads are located in protected areas or are in contact with them (including Natura 2000 sites). Therefore, it is important to understand the scope of the roads' ecological impacts and find ways for their appropriate evaluation and incorporation into the Environmental Impact Assessment process. For this reason, the Ecologicalmore » Impact Assessment methodology can be used as a basis for our research, which consists of three stages. In the first stage (scoping), a buffer circumventing the proposed road is created to determine the area for impact prediction and evaluation. Subsequently, the landscape structure and baseline landscape conditions are discussed, a map of current landscape structure is created and the current ecological status of the affected area is calculated. In the second stage (the evaluation of ecological resources), important ecological parts of the landscape are delineated. This step is based on the importance of previous information and its vulnerability, and leads to the mapping of the road ecological impact zone. In the third stage (impact assessment), important ecological parts are spatially correlated with the proposed road construction. Finally, the significance of ecological impacts of the activity is evaluated by applying specific criteria (duration, reversibility, magnitude, size and road ecological impact zone significance). A scale is proposed for each criterion to evaluate the total significance of impacts. In this way, detailed significant ecological impacts can be found which will help lead to proposed correct mitigation measures and a post-project analysis. - Highlights: • This paper proposes a methodology for the EcIA of road construction. • It tries to understand the spatial structure and configuration of landscape elements. • The most important ecological parts within the territory are identified. • The total significance of ecological receptors is evaluated by applying criteria.« less
Font, Anna; Baker, Timothy; Mudway, Ian S; Purdie, Esme; Dunster, Christina; Fuller, Gary W
2014-11-01
Road widening schemes in urban areas are often proposed as a solution to traffic congestion and as a means of stimulating economic growth. There is however clear evidence that new or expanded roads rapidly fill with either displaced or induced traffic, offsetting any short-term gains in eased traffic flows. What has not been addressed in any great detail is the impact of such schemes on air quality, with modelled impact predictions seldom validated by measurements after the expansion of road capacity. In this study we made use of a road widening project in London to investigate the impact on ambient air quality (particulate matter, NOX, NO2) during and after the completion of the road works. PM10 increased during the construction period up to 15 μg m(-3) during working hours compared to concentrations before the road works. A box modelling approach was used to determine a median emission factor of 0.0022 kg PM10 m(-2) month(-1), three times larger than that used in the UK emission inventory (0.0007 kg PM10 m(-2) month(-1)). Peaks of activity released 0.0130 kg PM10 m(-2) month(-1), three and eight times smaller than the peak values used in the European and US inventories. After the completion of the widening there was an increase in all pollutants from the road during rush hour: 2-4 μg m(-3) for PM10; 1 μg m(-3) for PM2.5; 40 and 8 μg m(-3) for NOX and NO2, respectively. NO2 EU Limit Value was breached after the road development illustrating a notable deterioration in residential air quality. Additionally, PM10, but not PM2.5, glutathione dependent oxidative potential increased after the road was widened consistent with an increase in pro-oxidant components in the coarse particle mode, related to vehicle abrasion processes. These increased air pollution indices were associated with an increase in the number of cars, taxis and LGVs. Copyright © 2014. Published by Elsevier B.V.
The effects of roadway characteristics on farm equipment crashes: A GIS approach
NASA Astrophysics Data System (ADS)
Greenan, Mitchell Joseph
Tractors and other self-propelled farm equipment, such as combines, sprayers, and towed grain carts, are often used on public roadways as the primary means for traveling from homestead to homestead or from homestead to a distributer. Increased roadway exposure has led to a growing concern for crashes involving farm equipment on the public roadway. A handful of studies exist examining public roadway crashes involving farm equipment using crash data, but none thus far have evaluated road segment data to identify road-specific risk factors. The objective of this study is to identify if roadway characteristics (traffic density, speed limit, road type, surface type, road width, and shoulder width) affect the risk of a crash involving farm equipment on Iowa public roadways. A retrospective cohort study of Iowa roads was conducted to identify the types of roads that are at an increased risk of having a farm-equipment crash on them. Crash data from the Iowa Department of Transportation (to identify crashes) were spatial linked to Iowa roadway data using Geographic Information Systems (GIS). Logistic regression was used to calculate ORs and 95% CL. Out of 319,705 road segments in Iowa, 0.4% segments (n=1,337) had a farm equipment crash from 2005-2011. The odds of having a farm equipment crash were significantly higher for road segments with increased traffic density and speed limit. Roads with an average daily traffic volume of at least 1,251 vehicles were at a 5.53 times greater odds of having a crash than roads with a daily traffic volume between 0-30 vehicles. (CI: 3.90-7.83). Roads with a posted speed limit between 50mph and 60mph were at a 4.88 times greater odds of having a crash than roads with a posted speed limit of 30mph or less. (CI: 3.85-6.20). Specific roadway characteristics such as roadway and shoulder width were also associated with the risk of a crash. For every 5 foot increase in road width, the odds for a crash decreased by 6 percent (CI: 0.89-0.99) and for every 5 foot increase in shoulder width, the odds of a crash decreased by 8 percent. (CI: 0.86-0.98). Although not statically significant, unpaved roads increased the odds of a crash by 17 percent. (CI: 0.91-1.50) Lastly, it was found that Farm to Market routes increased the odds of a crash by two fold compared to local roads (which make up roughly 67 percent of Iowa public roads). (CI: 1.72-2.43) When the same model was stratified by rurality (urban/rural), it was found that high traffic density leads to a higher risk of a crash in rural areas. Iowa routes and Farm to Market routes had a greater odds of a crash in urban than rural areas, and road and shoulder width were more protective in rural than urban areas. When only using roads with a crash involving an injury versus all other roads as the outcome, Iowa routes and roads with increased speed limits had higher odds for an injury-involved crash, while increased road width were more protective against crashes involving injuries. Findings from the study suggest that several roadway characteristics were associated with farm-equipment crashes. Through administrative and engineering controls, the six static explanatory variables used in this study may be modified to decrease the risk of a farm equipment crash. Speed limit can be modified through administrative controls while traffic density, road and shoulder width, road type, and surface type can be modified through engineering controls. Results from this study provide information that will aid policy-makers in developing safer roads for farm equipment.
2007-05-14
KENNEDY SPACE CENTER, FLA. -- This young alligator crosses a road near the railroad tracks where the train carrying solid rocket booster motor segments approaches Kennedy Space Center. Photo credit: NASA/George Shelton
NASA Astrophysics Data System (ADS)
Ke, Haohao; Ondov, John M.; Rogge, Wolfgang F.
2013-12-01
Composite chemical profiles of motor vehicle emissions were extracted from ambient measurements at a near-road site in Baltimore during a windless traffic episode in November, 2002, using four independent approaches, i.e., simple peak analysis, windless model-based linear regression, PMF, and UNMIX. Although the profiles are in general agreement, the windless-model-based profile treatment more effectively removes interference from non-traffic sources and is deemed to be more accurate for many species. In addition to abundances of routine pollutants (e.g., NOx, CO, PM2.5, EC, OC, sulfate, and nitrate), 11 particle-bound metals and 51 individual traffic-related organic compounds (including n-alkanes, PAHs, oxy-PAHs, hopanes, alkylcyclohexanes, and others) were included in the modeling.
Dynamics of functional failures and recovery in complex road networks
NASA Astrophysics Data System (ADS)
Zhan, Xianyuan; Ukkusuri, Satish V.; Rao, P. Suresh C.
2017-11-01
We propose a new framework for modeling the evolution of functional failures and recoveries in complex networks, with traffic congestion on road networks as the case study. Differently from conventional approaches, we transform the evolution of functional states into an equivalent dynamic structural process: dual-vertex splitting and coalescing embedded within the original network structure. The proposed model successfully explains traffic congestion and recovery patterns at the city scale based on high-resolution data from two megacities. Numerical analysis shows that certain network structural attributes can amplify or suppress cascading functional failures. Our approach represents a new general framework to model functional failures and recoveries in flow-based networks and allows understanding of the interplay between structure and function for flow-induced failure propagation and recovery.
NASA Astrophysics Data System (ADS)
Krapukhina, Nina; Senchenko, Roman; Kamenov, Nikolay
2017-12-01
Road safety and driving in dense traffic flows poses some challenges in receiving information about surrounding moving object, some of which can be in the vehicle's blind spot. This work suggests an approach to virtual monitoring of the objects in a current road scene via a system with a multitude of cooperating smart vehicles exchanging information. It also describes the intellectual agent model, and provides methods and algorithms of identifying and evaluating various characteristics of moving objects in video flow. Authors also suggest ways for integrating the information from the technical vision system into the model with further expansion of virtual monitoring for the system's objects. Implementation of this approach can help to expand the virtual field of view for a technical vision system.
Robust Lane Sensing and Departure Warning under Shadows and Occlusions
Tapia-Espinoza, Rodolfo; Torres-Torriti, Miguel
2013-01-01
A prerequisite for any system that enhances drivers' awareness of road conditions and threatening situations is the correct sensing of the road geometry and the vehicle's relative pose with respect to the lane despite shadows and occlusions. In this paper we propose an approach for lane segmentation and tracking that is robust to varying shadows and occlusions. The approach involves color-based clustering, the use of MSAC for outlier removal and curvature estimation, and also the tracking of lane boundaries. Lane boundaries are modeled as planar curves residing in 3D-space using an inverse perspective mapping, instead of the traditional tracking of lanes in the image space, i.e., the segmented lane boundary points are 3D points in a coordinate frame fixed to the vehicle that have a depth component and belong to a plane tangent to the vehicle's wheels, rather than 2D points in the image space without depth information. The measurement noise and disturbances due to vehicle vibrations are reduced using an extended Kalman filter that involves a 6-DOF motion model for the vehicle, as well as measurements about the road's banking and slope angles. Additional contributions of the paper include: (i) the comparison of textural features obtained from a bank of Gabor filters and from a GMRF model; and (ii) the experimental validation of the quadratic and cubic approximations to the clothoid model for the lane boundaries. The results show that the proposed approach performs better than the traditional gradient-based approach under different levels of difficulty caused by shadows and occlusions. PMID:23478598
Rehfuess, Eva A; Durão, Solange; Kyamanywa, Patrick; Meerpohl, Joerg J; Young, Taryn; Rohwer, Anke
2016-04-01
To derive evidence-based and stakeholder-informed research priorities for implementation in African settings, the international research consortium Collaboration for Evidence-Based Healthcare and Public Health in Africa (CEBHA+) developed and applied a pragmatic approach. First, an online survey and face-to-face consultation between CEBHA+ partners and policy-makers generated priority research areas. Second, evidence maps for these priority research areas identified gaps and related priority research questions. Finally, study protocols were developed for inclusion within a grant proposal. Policy and practice representatives were involved throughout the process. Tuberculosis, diabetes, hypertension and road traffic injuries were selected as priority research areas. Evidence maps covered screening and models of care for diabetes and hypertension, population-level prevention of diabetes and hypertension and their risk factors, and prevention and management of road traffic injuries. Analysis of these maps yielded three priority research questions on hypertension and diabetes and one on road traffic injuries. The four resulting study protocols employ a broad range of primary and secondary research methods; a fifth promotes an integrated methodological approach across all research activities. The CEBHA+ approach, in particular evidence mapping, helped to formulate research questions and study protocols that would be owned by African partners, fill gaps in the evidence base, address policy and practice needs and be feasible given the existing research infrastructure and expertise. The consortium believes that the continuous involvement of decision-makers throughout the research process is an important means of ensuring that studies are relevant to the African context and that findings are rapidly implemented.
A hybrid clustering and classification approach for predicting crash injury severity on rural roads.
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.
An integrated approach to assess heavy metal source apportionment in peri-urban agricultural soils.
Huang, Ying; Li, Tingqiang; Wu, Chengxian; He, Zhenli; Japenga, Jan; Deng, Meihua; Yang, Xiaoe
2015-12-15
Three techniques (Isotope Ratio Analysis, GIS mapping, and Multivariate Statistical Analysis) were integrated to assess heavy metal pollution and source apportionment in peri-urban agricultural soils. The soils in the study area were moderately polluted with cadmium (Cd) and mercury (Hg), lightly polluted with lead (Pb), and chromium (Cr). GIS Mapping suggested Cd pollution originates from point sources, whereas Hg, Pb, Cr could be traced back to both point and non-point sources. Principal component analysis (PCA) indicated aluminum (Al), manganese (Mn), nickel (Ni) were mainly inherited from natural sources, while Hg, Pb, and Cd were associated with two different kinds of anthropogenic sources. Cluster analysis (CA) further identified fertilizers, waste water, industrial solid wastes, road dust, and atmospheric deposition as potential sources. Based on isotope ratio analysis (IRA) organic fertilizers and road dusts accounted for 74-100% and 0-24% of the total Hg input, while road dusts and solid wastes contributed for 0-80% and 19-100% of the Pb input. This study provides a reliable approach for heavy metal source apportionment in this particular peri-urban area, with a clear potential for future application in other regions. Copyright © 2015 Elsevier B.V. All rights reserved.
An approach for multi-objective optimization of vehicle suspension system
NASA Astrophysics Data System (ADS)
Koulocheris, D.; Papaioannou, G.; Christodoulou, D.
2017-10-01
In this paper, a half car model of with nonlinear suspension systems is selected in order to study the vertical vibrations and optimize its suspension system with respect to ride comfort and road holding. A road bump was used as road profile. At first, the optimization problem is solved with the use of Genetic Algorithms with respect to 6 optimization targets. Then the k - ɛ optimization method was implemented to locate one optimum solution. Furthermore, an alternative approach is presented in this work: the previous optimization targets are separated in main and supplementary ones, depending on their importance in the analysis. The supplementary targets are not crucial to the optimization but they could enhance the main objectives. Thus, the problem was solved again using Genetic Algorithms with respect to the 3 main targets of the optimization. Having obtained the Pareto set of solutions, the k - ɛ optimality method was implemented for the 3 main targets and the supplementary ones, evaluated by the simulation of the vehicle model. The results of both cases are presented and discussed in terms of convergence of the optimization and computational time. The optimum solutions acquired from both cases are compared based on performance metrics as well.
The improved degree of urban road traffic network: A case study of Xiamen, China
NASA Astrophysics Data System (ADS)
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.
Methodological development for selection of significant predictors explaining fatal road accidents.
Dadashova, Bahar; Arenas-Ramírez, Blanca; Mira-McWilliams, José; Aparicio-Izquierdo, Francisco
2016-05-01
Identification of the most relevant factors for explaining road accident occurrence is an important issue in road safety research, particularly for future decision-making processes in transport policy. However model selection for this particular purpose is still an ongoing research. In this paper we propose a methodological development for model selection which addresses both explanatory variable and adequate model selection issues. A variable selection procedure, TIM (two-input model) method is carried out by combining neural network design and statistical approaches. The error structure of the fitted model is assumed to follow an autoregressive process. All models are estimated using Markov Chain Monte Carlo method where the model parameters are assigned non-informative prior distributions. The final model is built using the results of the variable selection. For the application of the proposed methodology the number of fatal accidents in Spain during 2000-2011 was used. This indicator has experienced the maximum reduction internationally during the indicated years thus making it an interesting time series from a road safety policy perspective. Hence the identification of the variables that have affected this reduction is of particular interest for future decision making. The results of the variable selection process show that the selected variables are main subjects of road safety policy measures. Published by Elsevier Ltd.
Market Segmentation and the Restructuring of Banking Jobs. IEE Brief Number 24.
ERIC Educational Resources Information Center
Hughes, Katherine; Bernhardt, Annette
The banking industry has undergone marked changes over the past 20 years, driven by deregulation and new technologies. Two strategies have emerged: the low-cost transaction approach and the high-road relationship banking approach. The number of employees in commercial banking has fallen significantly, and average hourly earnings for nonmanagerial…
30 CFR 56.6130 - Explosive material storage facilities.
Code of Federal Regulations, 2011 CFR
2011-07-01
... authorities for over-the-road use. Facilities other than magazines used to store blasting agents shall contain... appropriate warning signs that indicate the contents and are visible from each approach. ...
30 CFR 56.6130 - Explosive material storage facilities.
Code of Federal Regulations, 2010 CFR
2010-07-01
... authorities for over-the-road use. Facilities other than magazines used to store blasting agents shall contain... appropriate warning signs that indicate the contents and are visible from each approach. ...
30 CFR 56.6130 - Explosive material storage facilities.
Code of Federal Regulations, 2013 CFR
2013-07-01
... authorities for over-the-road use. Facilities other than magazines used to store blasting agents shall contain... appropriate warning signs that indicate the contents and are visible from each approach. ...
Influencing factors on the visibility of surface distresses
NASA Astrophysics Data System (ADS)
Smęt, Wojciech; Skakuj, Marek
2018-05-01
A systematic and future-oriented maintenance management requires quality-assured data regarding the condition of the roadway. An important characteristic for assessing the condition of the road surface are cracks [1]. Experience has proven that the road surface temperature and residual humidity can influence the visibility of cracks. To investigate and quantify these influencing factors in more detail, the Federal Ministry of Transport and Digital Infrastructure has implemented a comprehensive research project [2], during which several measurement campaigns were carried out at different seasons and at different temperatures and humidity degrees of the road surface. The visibility of the cracks was assessed using the German approach ZTV ZEB-StB [3]. After evaluating the cracks, the data was synchronized and the network allocation of the geo-referenced raw data was realized. The relevant condition performance indicators were calculated subsequently. For each evaluation section of 100 meters length, the mean road surface temperature was calculated and, if available, the type and year of construction of the surface course was determined. The evaluated data was visualized to establish correlations between the data and the influencing factors. For the statistical analysis of the results, a total of six comparative scenarios were defined in which the influencing factors of road surface temperature and residual humidity were assessed. This paper documents the results of the research project. In order to obtain a uniform and comparable picture of the condition of the road surface over the years and thus to be able to observe the aging process of the road surface, the measurement campaigns are to be carried out under defined conditions. The research project included proposals for defining and further specifying the measurement conditions.
Marshall, Wesley E
2018-02-01
Despite similarities to the US in terms of transportation, land use, and culture, Australia kills 5.3 people per 100,000 population on the roads each year, as compared to the US rate of 12.4. Similar trends hold when accounting for distance driven and the number of registered cars. This paper seeks to understand what is behind the road safety disparities between these two countries. The results suggest that a number of inter-related factors seem to play a role in the better road safety outcomes of Australia as compared to the US. This includes Australia's strategies related to seat belt usage and impaired driving as well as their efforts to help curb vehicle speeds and reduce exposure. Design-related differences include a much greater reliance on roundabouts and narrower street cross-sections as well as guidelines that encourage self-enforcing roads. Policy-related differences include stronger and more extensive enforcement programs, restrictive licensing programs, and higher driving costs. Combined with a more urban population and multimodal infrastructure, Australia tends to discourage driving mileage and exposure while encouraging safer modes of transportation such as transit, at least more so than in most of the US. Australia also enacted their version of Vision Zero - called the Safe System Approach - more than a decade before similar policies began cropping up in US cities. While it is difficult to attribute recent road safety successes to any specific policy, Australia continues to expand their lead on the US in terms of safety outcomes and is a road safety example worthy of consideration. Copyright © 2017 Elsevier Ltd. All rights reserved.
Sanusi, Adebayo Adesola; Emmelin, Maria
2015-01-01
Road traffic injury is a great public health challenge with an emerging trend of increasing rates and high mortality involving commercial motorcycles in Nigeria. A qualitative approach was used with 10 in-depth interviews conducted to explore the risk perceptions of commercial motorcyclists in Ibadan, Nigeria. The data analysis using manifest and latent content analysis resulted in an overarching theme: inadequate structures and internalised norms prevent change. The three themes leading to the overarching theme are: risk-taking as generally acceptable; risk-taking as an intrinsic part of occupation; and risk-taking as a way to make ends meet. The study suggests that there is a great need for adequate regulation as regards training and licensing of riders. Also the need to tighten enforcement of traffic rules is paramount to road safety in Nigeria.
Relationship between road traffic noisescape and urban form in Hong Kong.
Lam, Kin-Che; Ma, Weichun; Chan, Pak Kin; Hui, Wing Chi; Chung, King Lam; Chung, Yi-tak Teresa; Wong, Chun Yin; Lin, Hui
2013-12-01
This paper reports on a study which explored the possible relationship between road traffic noisescape and urban form in Hong Kong. A total of 212 residential complexes from 11 contrasting urban forms were sampled, and their noise levels assessed both at dwelling and neighbourhood scales by noise mapping. Its findings indicate that residential complexes with different urban forms have significantly different noisescape attributes. There is a strong correlation between the noise characteristics and morphological indicators at the dwelling scale. A less obstreperous noisescape is associated with urban forms with lower road and building densities, and with building arrangements which provide self-noise screening. These findings suggest that urban form is an influential determinant of the noisescape in the urban environment, and they point to the need to rethink the conventional approach to managing the urban acoustic environment.
Geophysical logging data from the Mills Gap Road area near Asheville, North Carolina
Chapman, Melinda J.; Huffman, Brad A.
2011-01-01
In September 2009, the U.S. Geological Survey (USGS) was requested to assist the Environmental Protection Agency (EPA) Region 4 Superfund Section in the development of a conceptual groundwater flow model in the area of the Mills Gap Road contaminant investigation near Asheville, North Carolina (Site ID A4P5) through an Interagency Grant and work authorization IAD DW number 14946085. The USGS approach included the application of established and state-of-the-science borehole geophysical tools and methods used to delineate and characterize fracture zones in the regolith-fractured bedrock groundwater system. Borehole geophysical logs were collected in eight wells in the Mills Gap Road project area from January through June 2010. These subsurface data were compared to local surface geologic mapping data collected by the North Carolina Geological Survey (NCGS) from January through May 2010.
Specific features of goal setting in road traffic safety
NASA Astrophysics Data System (ADS)
Kolesov, V. I.; Danilov, O. F.; Petrov, A. I.
2017-10-01
Road traffic safety (RTS) management is inherently a branch of cybernetics and therefore requires clear formalization of the task. The paper aims at identification of the specific features of goal setting in RTS management under the system approach. The paper presents the results of cybernetic modeling of the cause-to-effect mechanism of a road traffic accident (RTA); in here, the mechanism itself is viewed as a complex system. A designed management goal function is focused on minimizing the difficulty in achieving the target goal. Optimization of the target goal has been performed using the Lagrange principle. The created working algorithms have passed the soft testing. The key role of the obtained solution in the tactical and strategic RTS management is considered. The dynamics of the management effectiveness indicator has been analyzed based on the ten-year statistics for Russia.
Benoit, Gaëlle; Heinkélé, Christophe; Gourdon, Emmanuel
2013-12-01
This paper deals with a numerical procedure to identify the acoustical parameters of road pavement from surface impedance measurements. This procedure comprises three steps. First, a suitable equivalent fluid model for the acoustical properties porous media is chosen, the variation ranges for the model parameters are set, and a sensitivity analysis for this model is performed. Second, this model is used in the parameter inversion process, which is performed with simulated annealing in a selected frequency range. Third, the sensitivity analysis and inversion process are repeated to estimate each parameter in turn. This approach is tested on data obtained for porous bituminous concrete and using the Zwikker and Kosten equivalent fluid model. This work provides a good foundation for the development of non-destructive in situ methods for the acoustical characterization of road pavements.
NASA Astrophysics Data System (ADS)
Chen, Long; Bian, Mingyuan; Luo, Yugong; Qin, Zhaobo; Li, Keqiang
2016-01-01
In this paper, a resonance frequency-based tire-road friction coefficient (TRFC) estimation method is proposed by considering the dynamics performance of the in-wheel motor drive system under small slip ratio conditions. A frequency response function (FRF) is deduced for the drive system that is composed of a dynamic tire model and a simplified motor model. A linear relationship between the squared system resonance frequency and the TFRC is described with the FRF. Furthermore, the resonance frequency is identified by the Auto-Regressive eXogenous model using the information of the motor torque and the wheel speed, and the TRFC is estimated thereafter by a recursive least squares filter with the identified resonance frequency. Finally, the effectiveness of the proposed approach is demonstrated through simulations and experimental tests on different road surfaces.
NASA Astrophysics Data System (ADS)
Wang, Fei; Chen, Hong; Guo, Konghui; Cao, Dongpu
2017-09-01
The path following and directional stability are two crucial problems when a road vehicle experiences a tire blow-out or sudden tire failure. Considering the requirement of rapid road vehicle motion control during a tire blow-out, this article proposes a novel linearized decoupling control procedure with three design steps for a class of second order multi-input-multi-output non-affine system. The evaluating indicators for controller performance are presented and a performance related control parameter distribution map is obtained based on the stochastic algorithm which is an innovation for non-blind parameter adjustment in engineering implementation. The analysis on the robustness of the proposed integrated controller is also performed. The simulation studies for a range of driving conditions are conducted, to demonstrate the effectiveness of the proposed controller.
Superposition of polarized waves at layered media: theoretical modeling and measurement
NASA Astrophysics Data System (ADS)
Finkele, Rolf; Wanielik, Gerd
1997-12-01
The detection of ice layers on road surfaces is a crucial requirement for a system that is designed to warn vehicle drivers of hazardous road conditions. In the millimeter wave regime at 76 GHz the dielectric constant of ice and conventional road surface materials (i.e. asphalt, concrete) is found to be nearly similar. Thus, if the layer of ice is very thin and thus is of the same shape of roughness as the underlying road surface it cannot be securely detected using conventional algorithmic approaches. The method introduced in this paper extents and applies the theoretical work of Pancharatnam on the superposition of polarized waves. The projection of the Stokes vectors onto the Poincare sphere traces a circle due to the variation of the thickness of the ice layer. The paper presents a method that utilizes the concept of wave superposition to detect this trace even if it is corrupted by stochastic variation due to rough surface scattering. Measurement results taken under real traffic conditions prove the validity of the proposed algorithms. Classification results are presented and the results discussed.
Improving the Safety of Aging Road Users – A Mini-Review
Boot, Walter R.; Stothart, Cary; Charness, Neil
2014-01-01
Older drivers are at greatest risk for injury or death as a result of a car crash. In this mini-review we outline the normative age-related changes to perceptual, cognitive, and motor abilities that contribute to increased crash risk and decreased comfort with driving, and highlight specific driving scenarios and conditions that are particularly challenging for aging road users. Adopting a person-environment fit framework, we discuss how the roadway environment can be modified to better match the abilities of the aging driver. We also review evidence for the efficacy of training interventions intent on changing the abilities and strategies of the aging driver to better match the demands of the driving environment. Evidence suggests that specific changes to the roadway and driver training strategies can bring the abilities of the older driver back into alignment with the demands of the driving task. A focus on both approaches will help ensure the safety of all road users as the number of aging road users greatly increases over the next few decades. PMID:23989044
Mendonça, C; Freitas, E; Ferreira, J P; Raimundo, I D; Santos, J A
2013-03-01
Road traffic sounds are a major source of noise pollution in urban areas. But recent developments such as low noise pavements and hybrid/electric engine vehicles cast an optimistic outlook over such an environmental problem. However, it can be argued that engine, tire, and road noise could be relevant sources of information to avoid road traffic conflicts and accidents. In this paper, we analyze the potential trade-offs of traffic-noise abatement approaches in an experimental study, focusing for the first time on the impact and interaction of relevant factors such as pavement type, vehicle type, listener's age, and background noise, on vehicle detection levels. Results reveal that vehicle and pavement type significantly affect vehicle detection. Age is a significant factor, as both younger and older people exhibit lower detection levels of incoming vehicles. Low noise pavements combined with all-electric and hybrid vehicles might pose a severe threat to the safety of vulnerable road users. All factors interact simultaneously, and vehicle detection is best predicted by the loudness signal-to-noise ratio. Copyright © 2012 Elsevier Ltd. All rights reserved.
Experience of the ARGO autonomous vehicle
NASA Astrophysics Data System (ADS)
Bertozzi, Massimo; Broggi, Alberto; Conte, Gianni; Fascioli, Alessandra
1998-07-01
This paper presents and discusses the first results obtained by the GOLD (Generic Obstacle and Lane Detection) system as an automatic driver of ARGO. ARGO is a Lancia Thema passenger car equipped with a vision-based system that allows to extract road and environmental information from the acquired scene. By means of stereo vision, obstacles on the road are detected and localized, while the processing of a single monocular image allows to extract the road geometry in front of the vehicle. The generality of the underlying approach allows to detect generic obstacles (without constraints on shape, color, or symmetry) and to detect lane markings even in dark and in strong shadow conditions. The hardware system consists of a PC Pentium 200 Mhz with MMX technology and a frame-grabber board able to acquire 3 b/w images simultaneously; the result of the processing (position of obstacles and geometry of the road) is used to drive an actuator on the steering wheel, while debug information are presented to the user on an on-board monitor and a led-based control panel.
The medico-legal aspects of road traffic deaths in children under 5 years of age.
Terranova, Claudio
2015-11-01
The family tragedy that results from a child who dies in a road traffic accident may be exacerbated by judicial consequences for the adult/parent driving the vehicle, carrying the child, or responsible for properly immobilising the child in the safety device that was used. The author presents two court cases of the road traffic accident deaths of two children under the age of five years. The two cases are presented using a methodological approach, which integrates competencies in other fields into the medico-legal aspects. An analysis of the two cases provides the opportunity to discuss the driver's responsibility to properly use child safety seat and to analyse and evaluate the efficacy and limits of child restraint systems. In the two cases, the responsibility for the application of a child safety device was excluded. It was confirmed that child protective devices are not always sufficient to avoid lesions or death in road accidents that occur with significant speed or other specific dynamics. Copyright © 2015 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.
A fuel-based approach to estimating motor vehicle exhaust emissions
NASA Astrophysics Data System (ADS)
Singer, Brett Craig
Motor vehicles contribute significantly to air pollution problems; accurate motor vehicle emission inventories are therefore essential to air quality planning. Current travel-based inventory models use emission factors measured from potentially biased vehicle samples and predict fleet-average emissions which are often inconsistent with on-road measurements. This thesis presents a fuel-based inventory approach which uses emission factors derived from remote sensing or tunnel-based measurements of on-road vehicles. Vehicle activity is quantified by statewide monthly fuel sales data resolved to the air basin level. Development of the fuel-based approach includes (1) a method for estimating cold start emission factors, (2) an analysis showing that fuel-normalized emission factors are consistent over a range of positive vehicle loads and that most fuel use occurs during loaded-mode driving, (3) scaling factors relating infrared hydrocarbon measurements to total exhaust volatile organic compound (VOC) concentrations, and (4) an analysis showing that economic factors should be considered when selecting on-road sampling sites. The fuel-based approach was applied to estimate carbon monoxide (CO) emissions from warmed-up vehicles in the Los Angeles area in 1991, and CO and VOC exhaust emissions for Los Angeles in 1997. The fuel-based CO estimate for 1991 was higher by a factor of 2.3 +/- 0.5 than emissions predicted by California's MVEI 7F model. Fuel-based inventory estimates for 1997 were higher than those of California's updated MVEI 7G model by factors of 2.4 +/- 0.2 for CO and 3.5 +/- 0.6 for VOC. Fuel-based estimates indicate a 20% decrease in the mass of CO emitted, despite an 8% increase in fuel use between 1991 and 1997; official inventory models predict a 50% decrease in CO mass emissions during the same period. Cold start CO and VOC emission factors derived from parking garage measurements were lower than those predicted by the MVEI 7G model. Current inventories in California appear to understate total exhaust CO and VOC emissions, while overstating the importance of cold start emissions. The fuel-based approach yields robust, independent, and accurate estimates of on-road vehicle emissions. Fuel-based estimates should be used to validate or adjust official vehicle emission inventories before society embarks on new, more costly air pollution control programs.
NASA Astrophysics Data System (ADS)
Santillan, J. R.; Amora, A. M.; Makinano-Santillan, M.; Marqueso, J. T.; Cutamora, L. C.; Serviano, J. L.; Makinano, R. M.
2016-06-01
In this paper, we present a combined geospatial and two dimensional (2D) flood modeling approach to assess the impacts of flooding due to extreme rainfall events. We developed and implemented this approach to the Tago River Basin in the province of Surigao del Sur in Mindanao, Philippines, an area which suffered great damage due to flooding caused by Tropical Storms Lingling and Jangmi in the year 2014. The geospatial component of the approach involves extraction of several layers of information such as detailed topography/terrain, man-made features (buildings, roads, bridges) from 1-m spatial resolution LiDAR Digital Surface and Terrain Models (DTM/DSMs), and recent land-cover from Landsat 7 ETM+ and Landsat 8 OLI images. We then used these layers as inputs in developing a Hydrologic Engineering Center Hydrologic Modeling System (HEC HMS)-based hydrologic model, and a hydraulic model based on the 2D module of the latest version of HEC River Analysis System (RAS) to dynamically simulate and map the depth and extent of flooding due to extreme rainfall events. The extreme rainfall events used in the simulation represent 6 hypothetical rainfall events with return periods of 2, 5, 10, 25, 50, and 100 years. For each event, maximum flood depth maps were generated from the simulations, and these maps were further transformed into hazard maps by categorizing the flood depth into low, medium and high hazard levels. Using both the flood hazard maps and the layers of information extracted from remotely-sensed datasets in spatial overlay analysis, we were then able to estimate and assess the impacts of these flooding events to buildings, roads, bridges and landcover. Results of the assessments revealed increase in number of buildings, roads and bridges; and increase in areas of land-cover exposed to various flood hazards as rainfall events become more extreme. The wealth of information generated from the flood impact assessment using the approach can be very useful to the local government units and the concerned communities within Tago River Basin as an aid in determining in an advance manner all those infrastructures (buildings, roads and bridges) and land-cover that can be affected by different extreme rainfall event flood scenarios.
30 CFR 57.6130 - Explosive material storage facilities.
Code of Federal Regulations, 2011 CFR
2011-07-01
... local authorities for over-the-road use. Facilities other than magazines used to store blasting agents... or other appropriate warning signs that indicate the contents and are visible from each approach. ...
30 CFR 57.6130 - Explosive material storage facilities.
Code of Federal Regulations, 2013 CFR
2013-07-01
... local authorities for over-the-road use. Facilities other than magazines used to store blasting agents... or other appropriate warning signs that indicate the contents and are visible from each approach. ...
30 CFR 57.6130 - Explosive material storage facilities.
Code of Federal Regulations, 2010 CFR
2010-07-01
... local authorities for over-the-road use. Facilities other than magazines used to store blasting agents... or other appropriate warning signs that indicate the contents and are visible from each approach. ...
Combined research effort on aggregate road materials
NASA Astrophysics Data System (ADS)
Kuznetsova, Elena; Hoff, Inge; Willy Danielsen, Svein; Wigum, Børge Johannes; Fladvad, Marit; Rieksts, Karlis; Loranger, Benoit; Barbieri, Diego
2017-04-01
In European countries, the average aggregate consumption per capita is 5 tons per year (European Aggregates Association 2016), while the corresponding number in Norway is 11 tons (Neeb 2015). Due to the increased demand for sand and gravel for construction purposes, e.g. in road construction, the last decade has seen a significant trend towards the use of crushed rock aggregates. Neeb (2015) reports that half of the Norwegian aggregate production (sand, gravel and crushed rock) is used for road construction, and 33 % of the overall sold tonnage of crushed rock is exported. This resource has been more and more preferred over sand and gravel due to the significant technological development of its process and utilization phase. In Norway, the development and implementation of crushed aggregate technology has been the main approach to solve natural resource scarcity (Danielsen and Kuznetsova 2015). In order to reduce aggregates transportation, it is aimed to use local aggregates and aggregates processed from rock excavations, tunneling, road cuts, etc. One issue focused in this research is the influence from blasting and processing on the final quality of the crushed aggregates, specifically relating to the properties for road construction purposes. It is therefor crucial to plan utilization of available materials for use in different road layers following the same production line. New developments and improved availability of mobile crushing and screening equipment could produce more sustainable and profitable sources of good quality aggregate materials from small volume deposits in proximity to construction sites. One of the biggest challenges today to use these materials is that the pavement design manual sets rigid requirements for pavement layers. Four research projects are being conducted in Norway to improve the use of local materials for road construction. Four aspects are to be covered by the research: a) geological characteristics of the materials, their b) mechanical and c) thermal properties, and d) frost action and susceptibility. The main goal of the PhD topic N1 is to achieve better utilization of aggregate resources through adjusting the production process according to local geological conditions and construction needs. The objective of the PhD project N2 is to look at the design stage and find the way to use these aggregates anyway by changing the road's design (e.g. increasing the thickness of asphalt layer). Fine particles content will also be harder to control due to rock type variability from site to site. Thus, PhD project N3 is going to investigate the effect of the increasing of fines and their mineralogy on frost action related problems during freezing and thawing seasons. Finally, PhD project N4 is investigating how the grading and mineralogy of the crushed rock material affects the heat exchange in road's granular layers and consequently, the frost penetration depth. Combining these PhD studies we aim to create a holistic approach for a new understanding within this very complex area.
NASA Astrophysics Data System (ADS)
Pandey, Apoorva; Venkataraman, Chandra
2014-12-01
Urbanization and rising household incomes in India have led to growing transport demand, particularly during 1990-2010. Emissions from transportation have been implicated in air quality and climate effects. In this work, emissions of particulate matter (PM2.5 or mass concentration of particles smaller than 2.5 um diameter), black carbon (BC) and organic carbon (OC), were estimated from the transport sector in India, using detailed technology divisions and regionally measured emission factors. Modes of transport addressed in this work include road transport, railways, shipping and aviation, but exclude off-road equipment like diesel machinery and tractors. For road transport, a vehicle fleet model was used, with parameters derived from vehicle sales, registration data, and surveyed age-profile. The fraction of extremely high emitting vehicles, or superemitters, which is highly uncertain, was assumed as 20%. Annual vehicle utilization estimates were based on regional surveys and user population. For railways, shipping and aviation, a top-down approach was applied, using nationally reported fuel consumption. Fuel use and emissions from on-road vehicles were disaggregated at the state level, with separate estimates for 30 cities in India. The on-road fleet was dominated by two-wheelers, followed by four-and three-wheelers, with new vehicles comprising the majority of the fleet for each vehicle type. A total of 276 (-156, 270) Gg/y PM2.5, 144 (-99, 207) Gg/y BC, and 95 (-64, 130) Gg/y OC emissions were estimated, with over 97% contribution from on-road transport. Largest emitters were identified as heavy duty diesel vehicles for PM2.5 and BC, but two-stroke vehicles and superemitters for OC. Old vehicles (pre-2005) contributed significantly more (∼70%) emissions, while their share in the vehicle fleet was smaller (∼45%). Emission estimates were sensitive to assumed superemitter fraction. Improvement of emission estimates requires on-road emission factor measurements for all vehicle types and a better understanding of vehicle utilization and superemitter fraction.
McKenzie, Grant; Janowicz, Krzysztof
2017-01-01
Gaining access to inexpensive, high-resolution, up-to-date, three-dimensional road network data is a top priority beyond research, as such data would fuel applications in industry, governments, and the broader public alike. Road network data are openly available via user-generated content such as OpenStreetMap (OSM) but lack the resolution required for many tasks, e.g., emergency management. More importantly, however, few publicly available data offer information on elevation and slope. For most parts of the world, up-to-date digital elevation products with a resolution of less than 10 meters are a distant dream and, if available, those datasets have to be matched to the road network through an error-prone process. In this paper we present a radically different approach by deriving road network elevation data from massive amounts of in-situ observations extracted from user-contributed data from an online social fitness tracking application. While each individual observation may be of low-quality in terms of resolution and accuracy, taken together they form an accurate, high-resolution, up-to-date, three-dimensional road network that excels where other technologies such as LiDAR fail, e.g., in case of overpasses, overhangs, and so forth. In fact, the 1m spatial resolution dataset created in this research based on 350 million individual 3D location fixes has an RMSE of approximately 3.11m compared to a LiDAR-based ground-truth and can be used to enhance existing road network datasets where individual elevation fixes differ by up to 60m. In contrast, using interpolated data from the National Elevation Dataset (NED) results in 4.75m RMSE compared to the base line. We utilize Linked Data technologies to integrate the proposed high-resolution dataset with OpenStreetMap road geometries without requiring any changes to the OSM data model.
NASA Astrophysics Data System (ADS)
Gurney, K. R.; Zhou, Y.; Geethakumar, S.; Godbole, A.; Mendoza, D. L.; Vaidhyanathan, M.; Sahni, N.
2009-12-01
The Vulcan Project has quantified 2002 fossil fuel CO2 for the US at the sub-county/hourly scale and is a key component of attributing CO2 fluxes within the North American Carbon Program. Vulcan approached quantification of CO2 emissions by leveraging information already contained within regulatory and monitoring agencies including the US EPA’s Acid Rain Program, the EPA’s National Emissions Inventory for the assessment of nationally regulated air pollution, the Department of Energy, the U.S. Census and the Department of Transportation. By utilizing the inventory emissions of carbon monoxide combined with fuel/device-specific emission factors, we have calculated CO2 emissions for industrial point sources, power plants, mobile sources, residential and commercial sectors with information on fuel used and source classification information. In this presentation, I provide critical recent advances in the Vulcan Project with particular emphasis on our contribution to the NACP mid-continent intensive campaign. Version 1.2 of the Vulcan fossil fuel CO2 emissions inventory includes the 2008 US Census road atlas, overcoming many of the missing roads and links that were prevalent in previous road atlas releases. This offers better spatial allocation of the onroad emissions. Figure 1 shows the improved road layer density for the MCI study region. Furthermore the temporal dimension of onroad emissions have been improved through the use of hourly traffic monitoring data at roughly 6000 monitoring locations across the US. The residential and commercial sector emissions now have hourly time structure via a spatially explicit heating degree day calculation utilizing the North American Regional Reanalysis temperature output. Finally, we have generated a multiyear (1997-2008) data product for the MCI region through use of Energy Information Administration state-level fuel sales data. Figure 1. improved road density via utilization of the new 2008 US census road layer. Left: previous Vulcan release road density; Right: latest Vulcan release road density
Design of a rotary for an uncontrolled multi-leg intersection in Chennai, India
NASA Astrophysics Data System (ADS)
Vasantha Kumar, S.; Gulati, Himanshu; Arora, Shivam
2017-11-01
One way to control the traffic at busy intersections is to construct a roundabout or rotary intersection, which is a special type of at-grade intersection, where all converging vehicles are forced to move round a central island in clock-wise direction. The present study aims to design a rotary for an uncontrolled multi leg intersection located in Royapetah in Chennai, India. The intersection has five approach roads with two-way traffic in all the approach roads and there is no signal or traffic police to control the traffic at present and hence experiences traffic chaos during peak hours. In order to design the rotary, it is essential to have the information on traffic volumes coming from the approach roads. For this, a video data collection was carried out for a duration of eight hours from 7.30 am to 11.30 am and from 2.30 pm to 6.30 pm on a typical working day using a handycam from the terrace of an apartment building located near the intersection. During data extraction stage, each 5 min. traffic volume was extracted for all the five classes of vehicles considered and were converted to passenger car units (PCU). The analysis of traffic data showed that during peak hour from 4.45 pm to 5.45 pm, the proportion of weaving traffic, i.e., ratio of sum of crossing streams to the total traffic on the weaving section was found to be 0.81. According to Indian road congress (IRC) guidelines, this proportion can take any value between 0.4 and 1 and in the present study, the calculated value is found to be within the prescribed range. Using the calculated values of average entry width of the rotary and width & length of weaving section, the practical capacity of the rotary was found to be 3020 PCUs which is well above the observed traffic volume of 2665 PCUs.
NASA Astrophysics Data System (ADS)
Patias, Petros; Giagkas, Fotis; Georgiadis, Charalampos; Mallinis, Giorgos; Kaimaris, Dimitris; Tsioukas, Vassileios
2017-09-01
Within the field of forestry, forest road mapping and inventory plays an important role in management activities related to wood harvesting industry, sentiment and water run-off modelling, biodiversity distribution and ecological connectivity, recreation activities, future planning of forest road networks and wildfire protection and fire-fighting. Especially in countries of the Mediterranean Rim, knowledge at regional and national scales regarding the distribution and the characteristics of rural and forest road network is essential in order to ensure an effective emergency management and rapid response of the fire-fighting mechanism. Yet, the absence of accurate and updated geodatabases and the drawbacks related to the use of traditional cartographic methods arising from the forest environment settings, and the cost and efforts needed, as thousands of meters need to be surveyed per site, trigger the need for new data sources and innovative mapping approaches. Monitoring the condition of unpaved forest roads with unmanned aerial vehicle technology is an attractive option for substituting objective, laboursome surveys. Although photogrammetric processing of UAV imagery can achieve accuracy of 1-2 centimeters and dense point clouds, the process is commonly based on the establishment of control points. In the case of forest road networks, which are linear features, there is a need for a great number of control points. Our aim is to evaluate low-cost UAV orthoimages generated over forest areas with GCP's captured from existing national scale aerial orthoimagery, satellite imagery available through a web mapping service (WMS), field surveys using Mobile Mapping System and GNSS receiver. We also explored the direct georeferencing potential through the GNSS onboard the low cost UAV. The results suggest that the GNSS approach proved to most accurate, while the positional accuracy derived using the WMS and the aerial orthoimagery datasets deemed satisfactory for the specific task at hand. The direct georeferencing procedure seems to be insufficient unless an onboard GNSS with improved specifications or Real-Time Kinematic (RTK) capabilities is used.
NASA Astrophysics Data System (ADS)
Michoud, Clément; Derron, Marc-Henri; Baumann, Valérie; Jaboyedoff, Michel; Rune Lauknes, Tom
2013-04-01
About 2'230 vehicles per day pass through the National Road 7 that link Buenos Aires to Santiago de Chile, crossing Andes Cordillera. This extremely important corridor, being the most important land pass between Argentina and Chile, is exposed to numerous natural hazards, such as snow avalanches, rockfalls and debris flows and remains closed by natural hazards several days per year. This goal of this study is to perform a regional mapping of geohazard susceptibilities along the Road 7 corridor, as started by Baumann et al. (2005), using modern remote sensing and numerical approaches with field checking. The area of interest is located in the Mendoza Province, between the villages Potrerillos and Las Cuevas near the Chilean border. The diversity of soil and rock conditions, the active geomorphological processes associated to post-glacial decompression, seasonal freeze and thaw and severe storms along the road corridor, increase the risk to natural hazard. With the support of the European Space Agency (ESA Category-1 Project 7154), we have in this study processed a large number of ERS and Envisat ASAR scenes, covering the period from 1995 to 2000. We applied both the small-baseline (SB) and the persistent scatterer (PSI) multi-temporal interferometric SAR (InSAR) techniques. The study area contains sparse vegetation, and the SB InSAR method is therefore well suited to map the area containing mainly distributed scatterers. Furthermore, PSI algorithms are also used for comparison for selected landslides in the inventory. Both approaches show a relatively good coherence within mountain areas, which is a good point for the landslide detections along the road. Indeed, the authors identified several large slope instabilities even active scree deposits. This inventory is finally compared with field observations and with existing susceptibility maps regarding snow avalanches, debris-flows and rockfalls. The final objective of this project is to develop a risk strategy that will help local authorities to manage the risk along this highway and also to provide guidelines.
NASA Astrophysics Data System (ADS)
Schlögl, Matthias; Laaha, Gregor
2017-04-01
The assessment of road infrastructure exposure to extreme weather events is of major importance for scientists and practitioners alike. In this study, we compare the different extreme value approaches and fitting methods with respect to their value for assessing the exposure of transport networks to extreme precipitation and temperature impacts. Based on an Austrian data set from 25 meteorological stations representing diverse meteorological conditions, we assess the added value of partial duration series (PDS) over the standardly used annual maxima series (AMS) in order to give recommendations for performing extreme value statistics of meteorological hazards. Results show the merits of the robust L-moment estimation, which yielded better results than maximum likelihood estimation in 62 % of all cases. At the same time, results question the general assumption of the threshold excess approach (employing PDS) being superior to the block maxima approach (employing AMS) due to information gain. For low return periods (non-extreme events) the PDS approach tends to overestimate return levels as compared to the AMS approach, whereas an opposite behavior was found for high return levels (extreme events). In extreme cases, an inappropriate threshold was shown to lead to considerable biases that may outperform the possible gain of information from including additional extreme events by far. This effect was visible from neither the square-root criterion nor standardly used graphical diagnosis (mean residual life plot) but rather from a direct comparison of AMS and PDS in combined quantile plots. We therefore recommend performing AMS and PDS approaches simultaneously in order to select the best-suited approach. This will make the analyses more robust, not only in cases where threshold selection and dependency introduces biases to the PDS approach but also in cases where the AMS contains non-extreme events that may introduce similar biases. For assessing the performance of extreme events we recommend the use of conditional performance measures that focus on rare events only in addition to standardly used unconditional indicators. The findings of the study directly address road and traffic management but can be transferred to a range of other environmental variables including meteorological and hydrological quantities.
NASA Astrophysics Data System (ADS)
Aljoumani, Basem; Kluge, Björn; sanchez, Josep; Wessolek, Gerd
2017-04-01
Highways and main roads are potential sources of contamination for the surrounding environment. High traffic rates result in elevated heavy metal concentrations in road runoff, soil and water seepage, which has attracted much attention in the recent past. Prediction of heavy metals transfer near the roadside into deeper soil layers are very important to prevent the groundwater pollution. This study was carried out on data of a number of lysimeters which were installed along the A115 highway (Germany) with a mean daily traffic of 90.000 vehicles per day. Three polyethylene (PE) lysimeters were installed at the A115 highway. They have the following dimensions: length 150 cm, width 100 cm, height 60 cm. The lysimeters were filled with different soil materials, which were recently used for embankment construction in Germany. With the obtained data, we will develop a time series analysis model to predict total and dissolved metal concentration in road runoff and in soil solution of the roadside embankments. The time series consisted of monthly measurements of heavy metals and was transformed to a stationary situation. Subsequently, the transformed data will be used to conduct analyses in the time domain in order to obtain the parameters of a seasonal autoregressive integrated moving average (ARIMA) model. Four phase approaches for identifying and fitting ARIMA models will be used: identification, parameter estimation, diagnostic checking, and forecasting. An automatic selection criterion, such as the Akaike information criterion, will use to enhance this flexible approach to model building
Crawford, Brian A.; Moore, Clinton; Norton, Terry M.; Maerz, John C.
2018-01-01
A challenge for making conservation decisions is predicting how wildlife populations respond to multiple, concurrent threats and potential management strategies, usually under substantial uncertainty. Integrated modeling approaches can improve estimation of demographic rates necessary for making predictions, even for rare or cryptic species with sparse data, but their use in management applications is limited. We developed integrated models for a population of diamondback terrapins (Malaclemys terrapin) impacted by road-associated threats to (i) jointly estimate demographic rates from two mark-recapture datasets, while directly estimating road mortality and the impact of management actions deployed during the study; and (ii) project the population using population viability analysis under simulated management strategies to inform decision-making. Without management, population extirpation was nearly certain due to demographic impacts of road mortality, predators, and vegetation. Installation of novel flashing signage increased survival of terrapins that crossed roads by 30%. Signage, along with small roadside barriers installed during the study, increased population persistence probability, but the population was still predicted to decline. Management strategies that included actions targeting multiple threats and demographic rates resulted in the highest persistence probability, and roadside barriers, which increased adult survival, were predicted to increase persistence more than other actions. Our results support earlier findings showing mitigation of multiple threats is likely required to increase the viability of declining populations. Our approach illustrates how integrated models may be adapted to use limited data efficiently, represent system complexity, evaluate impacts of threats and management actions, and provide decision-relevant information for conservation of at-risk populations.
Willingness to pay for mortality risk reduction for traffic accidents in Myanmar.
Mon, Ei Ei; Jomnonkwao, Sajjakaj; Khampirat, Buratin; Satiennam, Wichuda; Ratanavaraha, Vatanavongs
2018-05-30
The dramatic increase in vehicle ownership in Myanmar over the past few years has resulted in an alarming increase in traffic accidents. Thus, road safety at the national level needs to be improved urgently in order to reduce the costs associated with traffic accidents and to assist policy makers in making economically efficient resource allocation decisions for road safety improvements. This research was conducted to determine the costs related to fatality risk reductions using a willingness to pay (WTP) approach for motorcyclists, car drivers, and bus passengers in Myanmar. Face-to-face interviews with contingent valuation (CV) and a payment card questionnaire approach was employed for the data collection; multiple linear regression analyses were conducted to determine the factors influencing WTP. The resulting median and mean for the value of statistical life (VSL) were found to be MMK 118.062 million (US$ 98,385) to MMK 162.854 million (US$ 135,712), respectively. Therefore, the total cost of death was estimated to range from MMK 594.681 billion (US$ 495.567 million) to MMK 820.296 billion (US$ 683.580 million) in 2015. In addition, the WTP was found to be significantly associated with age, family status, education, occupation, individual income, household income, the vehicle used, exposure to traffic, drunk driving, personal experiences, and the perceived risk of traffic accidents. This study might be helpful in prioritization of road safety related projects to get greatest benefit by choosing most cost effective projects. This study might assist the decision-making for road safety budget allocations and policy development. Copyright © 2018 Elsevier Ltd. All rights reserved.
[Socio-economic costs of road traffic accidents in the Canary Islands, Spain, in 1997].
López, J; Serrano, P; Duque, B; Artiles, J
2001-01-01
To evaluate the economic impact in terms of direct and indirect costs road traffic accidents in Canarias Islands (Spain) in 1997. The cost-of-illness method was used. Direct and indirect costs were estimated using prevalence cost, i.e., the costs produced in 1997. Direct costs were divided into health services costs, insurance administration costs and the costs of material damage to the vehicles. Indirect costs were obtained through transformation of physical units into monetary units using the approach of human capital theory. The total cost of road traffic accidents was 39,887.16 million pesetas, equivalent to 24,470 for each inhabitant of the Canary Islands and representing 1.3% of the GNP in this region. The total direct cost was 32,559.67 million pesetas, constituting 82% of the total, which was distributed according to the different concepts analyzed: health service costs: 2,407.40 million pesetas; insurance administration costs, 13,415.89 million pesetas and the costs of material damages to the vehicles: 16,736.38 million pesetas. The total indirect costs was 7,327.49 million pesetas, accounting for 18% of the total costs, which was distributed in premature mortality (6,884.88 million pesetas) and absenteeism from work (442.61 million pesetas). Although this study adopts a conservative approach by omitting costs associated with pain and suffering, permanent disability, and those of at-home care provided by the family, the hight socio-economic cost of road traffic accidents clearly indicates the need for the different administrations of the Canary Islands to collaborate in implementing preventive measures.
Pavement Performance : Approaches Using Predictive Analytics
DOT National Transportation Integrated Search
2018-03-23
Acceptable pavement condition is paramount to road safety. Using predictive analytics techniques, this project attempted to develop models that provide an assessment of pavement condition based on an array of indictors that include pavement distress,...
Code of Federal Regulations, 2010 CFR
2010-04-01
... PROCEDURES Bridges on Federal Dams § 630.803 Procedures. A State's application to qualify a project under... part of the agency constructing the dam to provide such bridge or approach roads to satisfy a legal...
Code of Federal Regulations, 2011 CFR
2011-04-01
... PROCEDURES Bridges on Federal Dams § 630.803 Procedures. A State's application to qualify a project under... part of the agency constructing the dam to provide such bridge or approach roads to satisfy a legal...
Restore McComas Meadows; Meadow Creek Watershed, 2003-2004 Annual Report.
DOE Office of Scientific and Technical Information (OSTI.GOV)
McRoberts, Heidi
2006-08-01
The Nez Perce Tribe Department of Fisheries Resource Management, Watershed Division approaches watershed restoration with a ridge-top to ridge-top approach. Watershed restoration projects within the Meadow Creek watershed are coordinated and cost shared with the Nez Perce National Forest. The Nez Perce Tribe began watershed restoration projects within the Meadow Creek watershed of the South Fork Clearwater River in 1996. Progress has been made in restoring the watershed by excluding cattle from critical riparian areas through fencing, planting trees in riparian areas within the meadow and its tributaries, prioritizing culverts for replacement to accommodate fish passage, and decommissioning roads tomore » reduce sediment input. Designs for culvert replacements are being coordinated with the Nez Perce National Forest. 20 miles of roads were decommissioned. Tribal crews completed maintenance to the previously built fence.« less
Rough set approach for accident chains exploration.
Wong, Jinn-Tsai; Chung, Yi-Shih
2007-05-01
This paper presents a novel non-parametric methodology--rough set theory--for accident occurrence exploration. The rough set theory allows researchers to analyze accidents in multiple dimensions and to model accident occurrence as factor chains. Factor chains are composed of driver characteristics, trip characteristics, driver behavior and environment factors that imply typical accident occurrence. A real-world database (2003 Taiwan single auto-vehicle accidents) is used as an example to demonstrate the proposed approach. The results show that although most accident patterns are unique, some accident patterns are significant and worth noting. Student drivers who are young and less experienced exhibit a relatively high possibility of being involved in off-road accidents on roads with a speed limit between 51 and 79 km/h under normal driving circumstances. Notably, for bump-into-facility accidents, wet surface is a distinctive environmental factor.
Can we prevent accidental injury to adolescents? A systematic review of the evidence.
Munro, J.; Coleman, P.; Nicholl, J.; Harper, R.; Kent, G.; Wild, D.
1995-01-01
OBJECTIVES: As part of the Department of Health strategy The Health of the Nation, a systematic review of published and unpublished literature relating to the effectiveness of interventions in reducing accidental injury in the population aged 15-24 years was carried out. METHODS: The literature was reviewed under the standard setting headings of road, work, home, and sports and leisure, and graded for quality of evidence and strength of recommendation using a scale published in the UK national epidemiologically based needs assessment programme. RESULTS: The most effective measures appear to be legislative and regulatory controls in road, sport, and workplace settings. Environmental engineering measures on the road and in sports have relatively low implementation costs and result in fewer injuries at all ages. There is little evidence that purely educational measures reduced injuries in the short term. Community based approaches may be effective in all age groups, and incentives to encourage safer behaviour hold promise but require further evaluation. The potential of multifactorial approaches seems greater than narrowly based linear approaches. CONCLUSIONS: Few interventions to reduce injury in adolescents have been rigorously evaluated using good quality randomised controlled trials, and where such evidence is available, fewer have been shown to be definitely worthwhile. Many studies relied on surrogate measures rather than actual injury rates, and substantial issues relating to the efficacy or implementation of preventive measures in adolescent and young adult populations remain unresolved. PMID:9346041
Liu, An; Wijesiri, Buddhi; Hong, Nian; Zhu, Panfeng; Egodawatta, Prasanna; Goonetilleke, Ashantha
2018-05-08
Road deposited pollutants (build-up) are continuously re-distributed by external factors such as traffic and wind turbulence, influencing stormwater runoff quality. However, current stormwater quality modelling approaches do not account for the re-distribution of pollutants. This undermines the accuracy of stormwater quality predictions, constraining the design of effective stormwater treatment measures. This study, using over 1000 data points, developed a Bayesian Network modelling approach to investigate the re-distribution of pollutant build-up on urban road surfaces. BTEX, which are a group of highly toxic pollutants, was the case study pollutants. Build-up sampling was undertaken in Shenzhen, China, using a dry and wet vacuuming method. The research outcomes confirmed that the vehicle type and particle size significantly influence the re-distribution of particle-bound BTEX. Compared to heavy-duty traffic in commercial areas, light-duty traffic dominates the re-distribution of particles of all size ranges. In industrial areas, heavy-duty traffic re-distributes particles >75 μm, and light-duty traffic re-distributes particles <75 μm. In residential areas, light-duty traffic re-distributes particles >300 μm and <75 μm and heavy-duty traffic re-distributes particles in the 300-150 μm range. The study results provide important insights to improve stormwater quality modelling and the interpretation of modelling outcomes, contributing to safeguard the urban water environment. Copyright © 2018 Elsevier B.V. All rights reserved.
The 2007 Feinberg lecture: a new road map for neuroprotection.
Donnan, Geoffrey A
2008-01-01
There have now been numerous phase III trials of neuroprotection that have failed to live up to the expectations created by preclinical testing in animal models, the most recent of which was the second pivotal trial of the spin trap agent NXY-059. We have reached a stage at which research in this area should stop altogether or radical new approaches adopted. The purpose of this article is to review how we reached this stage and make recommendations for a new approach to neuroprotection research. The background to neuroprotection research is reviewed and its problems are highlighted based on the research of others and of our own research group. From this, a series of questions are posed that require answers if the field is to progress. A road map for future research is then proposed. The road map involves the following steps for putative neuroprotectants: (1) better proof of efficacy in animal models; (2) in vivo evidence of efficacy in human tissue using cell cultures or brain slices; (3) in vivo studies of their distribution in the normal and ischemic human brain, particularly focusing on the ischemic penumbra; (4) demonstration of efficacy in novel human models of cerebral ischemia; and (5) phase II and III clinical trails with penumbral selection using imaging techniques. The accumulated evidence suggests that neuroprotection failure in clinical trial is due to identifiable preclinical and clinical factors. Neuroprotection research should be pursued but with a very different and more rigorous approach.
Vanthomme, Hadrien; Kolowski, Joseph; Nzamba, Brave S; Alonso, Alfonso
2015-10-01
The active field of connectivity conservation has provided numerous methods to identify wildlife corridors with the aim of reducing the ecological effect of fragmentation. Nevertheless, these methods often rely on untested hypotheses of animal movements, usually fail to generate fine-scale predictions of road crossing sites, and do not allow managers to prioritize crossing sites for implementing road fragmentation mitigation measures. We propose a new method that addresses these limitations. We illustrate this method with data from southwestern Gabon (central Africa). We used stratified random transect surveys conducted in two seasons to model the distribution of African forest elephant (Loxodonta cyclotis), forest buffalo (Syncerus caffer nanus), and sitatunga (Tragelaphus spekii) in a mosaic landscape along a 38.5 km unpaved road scheduled for paving. Using a validation data set of recorded crossing locations, we evaluated the performance of three types of models (local suitability, local least-cost movement, and regional least-cost movement) in predicting actual road crossings for each species, and developed a unique and flexible scoring method for prioritizing road sections for the implementation of road fragmentation mitigation measures. With a data set collected in <10 weeks of fieldwork, the method was able to identify seasonal changes in animal movements for buffalo and sitatunga that shift from a local exploitation of the site in the wet season to movements through the study site in the dry season, whereas elephants use the entire study area in both seasons. These three species highlighted the need to use species- and season-specific modeling of movement. From these movement models, the method ranked road sections for their suitability for implementing fragmentation mitigation efforts, allowing managers to adjust priority thresholds based on budgets and management goals. The method relies on data that can be obtained in a period compatible with environmental impact assessment constraints, and is flexible enough to incorporate other potential movement models and scoring criteria. This approach improves upon available methods and can help inform prioritization of road and other linear infrastructure segments that require impact mitigation methods to ensure long-term landscape connectivity.
ROAD MAP FOR DEVELOPMENT OF CRYSTAL-TOLERANT HIGH LEVEL WASTE GLASSES
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fox, K.; Peeler, D.; Herman, C.
The U.S. Department of Energy (DOE) is building a Tank Waste Treatment and Immobilization Plant (WTP) at the Hanford Site in Washington to remediate 55 million gallons of radioactive waste that is being temporarily stored in 177 underground tanks. Efforts are being made to increase the loading of Hanford tank wastes in glass while meeting melter lifetime expectancies and process, regulatory, and product quality requirements. This road map guides the research and development for formulation and processing of crystaltolerant glasses, identifying near- and long-term activities that need to be completed over the period from 2014 to 2019. The primary objectivemore » is to maximize waste loading for Hanford waste glasses without jeopardizing melter operation by crystal accumulation in the melter or melter discharge riser. The potential applicability to the Savannah River Site (SRS) Defense Waste Processing Facility (DWPF) will also be addressed in this road map. The planned research described in this road map is motivated by the potential for substantial economic benefits (significant reductions in glass volumes) that will be realized if the current constraints (T1% for WTP and TL for DWPF) are approached in an appropriate and technically defensible manner for defense waste and current melter designs. The basis of this alternative approach is an empirical model predicting the crystal accumulation in the WTP glass discharge riser and melter bottom as a function of glass composition, time, and temperature. When coupled with an associated operating limit (e.g., the maximum tolerable thickness of an accumulated layer of crystals), this model could then be integrated into the process control algorithms to formulate crystal-tolerant high-level waste (HLW) glasses targeting high waste loadings while still meeting process related limits and melter lifetime expectancies. The modeling effort will be an iterative process, where model form and a broader range of conditions, e.g., glass composition and temperature, will evolve as additional data on crystal accumulation are gathered. Model validation steps will be included to guide the development process and ensure the value of the effort (i.e., increased waste loading and waste throughput). A summary of the stages of the road map for developing the crystal-tolerant glass approach, their estimated durations, and deliverables is provided.« less
ERIC Educational Resources Information Center
Clarke, Angela; Cripps, Peter
2012-01-01
Curriculum and pedagogy in undergraduate fine art can promote an approach to learning creativity that is more about being an artist than knowing about art. Lecturers can provide a road map for developing particular dispositions, in relation to student ideas and perceptions, to foster personalised creativity. This requires that lecturers have an…
Case studies in corporate compliance: putting the rubber to the road.
Shah, Udayan K; Schmidt, Richard J; Hussain, S S Musheer; Cook, Steven P; Smith, Gina M; Ziv, Barbara E; Reilly, James S
2009-08-01
An interdisciplinary, proactive perspective allows providers to engage in productive, long-term collaborative relationships with corporations, while 1) maintaining patient care improvements; 2) maintaining legality; 3) enhancing technical and clinical innovation; and 4) providing fair compensation for work done. The case study approach is used to demonstrate an effective approach to compliant behavior.
Blue Road Approach to Special Relativity
ERIC Educational Resources Information Center
Huggins, Elisha
2012-01-01
In 1968, Robert Brehme wrote a carefully crafted paper on "The Advantage of Teaching Relativity with Four-Vectors." In his abstract he points out that "the emphasis on relativistic mass is both undeserved and misleading." Our approach is to find the best way to teach introductory physics in a way that includes modern physics. We have found that by…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Anthonissen, Joke, E-mail: joke.anthonissen@uantwerpen.be; Van den bergh, Wim, E-mail: wim.vandenbergh@uantwerpen.be; Braet, Johan, E-mail: johan.braet@uantwerpen.be
This paper provides a critical review of different approaches applied in the Belgian asphalt sector in order to reduce the environmental impact of bituminous road construction works. The focus is on (1) reusing reclaimed asphalt pavement, (2) reducing the asphalt production temperature, and (3) prolonging the service life of the pavement. Environmental impact assessment of these methods is necessary to be able to compare these approaches and understand better the ability to reduce the environmental impact during the life cycle of the road pavement. Attention should be drawn to the possible shift in environmental impact between various life cycle stages,more » e.g., raw material production, asphalt production, or waste treatment. Life cycle assessment is necessary to adequately assess the environmental impact of these approaches over the entire service life of the bituminous pavement. The three approaches and their implementation in the road sector in Flanders (region in Belgium) are described and the main findings from life cycle assessment studies on these subjects are discussed. It was found from the review that using reclaimed asphalt pavement in new bituminous mixtures might yield significant environmental gains. The environmental impact of the application of warm mix asphalt technologies, on the other hand, depends on the technique used. - Highlights: • Recycling, lower production temperature and durability of asphalt are investigated. • The use of RAP in new asphalt mixtures yields significant environmental advantages. • It would be beneficial to allow RAP in asphalt mixtures for wearing courses. • The use of particular additives might counteract the environmental gain from WMA. • The service life and the environmental data source influence the LCA results.« less
Samuel, Jonathan C; Sankhulani, Edward; Qureshi, Javeria S; Baloyi, Paul; Thupi, Charles; Lee, Clara N; Miller, William C; Cairns, Bruce A; Charles, Anthony G
2012-01-01
Road traffic injuries are a major cause of preventable death in sub-Saharan Africa. Accurate epidemiologic data are scarce and under-reporting from primary data sources is common. Our objectives were to estimate the incidence of road traffic deaths in Malawi using capture-recapture statistical analysis and determine what future efforts will best improve upon this estimate. Our capture-recapture model combined primary data from both police and hospital-based registries over a one year period (July 2008 to June 2009). The mortality incidences from the primary data sources were 0.075 and 0.051 deaths/1000 person-years, respectively. Using capture-recapture analysis, the combined incidence of road traffic deaths ranged 0.192-0.209 deaths/1000 person-years. Additionally, police data were more likely to include victims who were male, drivers or pedestrians, and victims from incidents with greater than one vehicle involved. We concluded that capture-recapture analysis is a good tool to estimate the incidence of road traffic deaths, and that capture-recapture analysis overcomes limitations of incomplete data sources. The World Health Organization estimated incidence of road traffic deaths for Malawi utilizing a binomial regression model and survey data and found a similar estimate despite strikingly different methods, suggesting both approaches are valid. Further research should seek to improve capture-recapture data through utilization of more than two data sources and improving accuracy of matches by minimizing missing data, application of geographic information systems, and use of names and civil registration numbers if available.
Gately, Conor K; Hutyra, Lucy R; Wing, Ian Sue; Brondfield, Max N
2013-03-05
On-road transportation is responsible for 28% of all U.S. fossil-fuel CO2 emissions. Mapping vehicle emissions at regional scales is challenging due to data limitations. Existing emission inventories use spatial proxies such as population and road density to downscale national or state-level data. Such procedures introduce errors where the proxy variables and actual emissions are weakly correlated, and limit analysis of the relationship between emissions and demographic trends at local scales. We develop an on-road emission inventory product for Massachusetts-based on roadway-level traffic data obtained from the Highway Performance Monitoring System (HPMS). We provide annual estimates of on-road CO2 emissions at a 1 × 1 km grid scale for the years 1980 through 2008. We compared our results with on-road emissions estimates from the Emissions Database for Global Atmospheric Research (EDGAR), with the Vulcan Product, and with estimates derived from state fuel consumption statistics reported by the Federal Highway Administration (FHWA). Our model differs from FHWA estimates by less than 8.5% on average, and is within 5% of Vulcan estimates. We found that EDGAR estimates systematically exceed FHWA by an average of 22.8%. Panel regression analysis of per-mile CO2 emissions on population density at the town scale shows a statistically significant correlation that varies systematically in sign and magnitude as population density increases. Population density has a positive correlation with per-mile CO2 emissions for densities below 2000 persons km(-2), above which increasing density correlates negatively with per-mile emissions.
NASA Astrophysics Data System (ADS)
Naulin, Jean-Philippe; Payrastre, Olivier; Gaume, Eric; Delrieu, Guy
2013-04-01
Accurate flood forecasts are crucial for an efficient flood event management. Until now, hydro-meteorological forecasts have been mainly used for early-warnings in France (Meteorological and flood vigilance maps) or over the world (Flash-flood guidances). These forecasts are generally limited to the main streams covered by the flood forecasting services or to specific watersheds with particular assets like check dams which are in most cases well gauged river sections, leaving aside large parts of the territory. A distributed hydro-meteorological forecasting approach will be presented, able to take advantage of the high spatial and temporal resolution rainfall estimates that are now available to provide information at ungauged sites. The proposed system aiming at detecting road inundation risks had been initially developed and tested in areas of limited size. Its extension to a whole region (the Gard region in the South of France) will be presented, including over 2000 crossing points between rivers and roads and its validation against a large data set of actually reported road inundations observed during recent flash-flood events. These first validation results appear promising. Such a tool would provide the necessary information for flood event management services to identify the areas at risk and to take the appropriate safety and rescue measures: pre-positioning of rescue means, stopping of the traffic on exposed roads, determination of safe accesses or evacuation routes. Moreover, beyond the specific application to the supervision of a road network, this work provides also results concerning the performances of hydro-meteorological forecasts for ungauged headwaters.
Samuel, Jonathan C.; Sankhulani, Edward; Qureshi, Javeria S.; Baloyi, Paul; Thupi, Charles; Lee, Clara N.; Miller, William C.; Cairns, Bruce A.; Charles, Anthony G.
2012-01-01
Road traffic injuries are a major cause of preventable death in sub-Saharan Africa. Accurate epidemiologic data are scarce and under-reporting from primary data sources is common. Our objectives were to estimate the incidence of road traffic deaths in Malawi using capture-recapture statistical analysis and determine what future efforts will best improve upon this estimate. Our capture-recapture model combined primary data from both police and hospital-based registries over a one year period (July 2008 to June 2009). The mortality incidences from the primary data sources were 0.075 and 0.051 deaths/1000 person-years, respectively. Using capture-recapture analysis, the combined incidence of road traffic deaths ranged 0.192–0.209 deaths/1000 person-years. Additionally, police data were more likely to include victims who were male, drivers or pedestrians, and victims from incidents with greater than one vehicle involved. We concluded that capture-recapture analysis is a good tool to estimate the incidence of road traffic deaths, and that capture-recapture analysis overcomes limitations of incomplete data sources. The World Health Organization estimated incidence of road traffic deaths for Malawi utilizing a binomial regression model and survey data and found a similar estimate despite strikingly different methods, suggesting both approaches are valid. Further research should seek to improve capture-recapture data through utilization of more than two data sources and improving accuracy of matches by minimizing missing data, application of geographic information systems, and use of names and civil registration numbers if available. PMID:22355338
NASA Astrophysics Data System (ADS)
Xing, Jing Tang; Sun, Zhe; Zhou, Sulian; Tan, Mingyi
2017-04-01
An investigation is undertaken of an integrated mechanical-electromagnetic coupling system consisting of a rigid vehicle with heave, roll, and pitch motions, four electromagnetic energy harvesters and four tires subject to uneven road excitations in order to improve the passengers' riding comfort and harvest the lost engine energy due to uneven roads. Following the derived mathematical formulations and the proposed solution approaches, the numerical simulations of this interaction system subject to a continuous sinusoidal road excitation and a single ramp impact are completed. The simulation results are presented as the dynamic response curves in the forms of the frequency spectrum and the time history, which reveals the complex interaction characteristics of the system for vibration reductions and energy harvesting performance. It has addressed the coupling effects on the dynamic characteristics of the integrated system caused by: (1) the natural modes and frequencies of the vehicle; (2) the vehicle rolling and pitching motions; (3) different road excitations on four wheels; (4) the time delay of a road ramp to impact both the front and rear wheels, etc., which cannot be tackled by an often used quarter vehicle model. The guidelines for engineering applications are given. The developed coupling model and the revealed concept provide a means with analysis idea to investigate the details of four energy harvester motions for electromagnetic suspension designs in order to replace the current passive vehicle isolators and to harvest the lost engine energy. Potential further research directions are suggested for readers to consider in the future.
Share the road campaign research study
DOT National Transportation Integrated Search
2011-01-01
SFpark is a demonstration of a new approach to parking management that will evaluate the effectiveness of demand-responsive pricing and real-time information on parking availability for reducing congestion and greenhouse gas emissions and provide oth...
Proactive approach to transportation resource allocation under severe winter weather emergencies.
DOT National Transportation Integrated Search
2012-01-01
Severe winter weather dramatically reduces road transportation infrastructure : serviceability and decreases safety throughout Oklahoma. Although it has relatively mild winters : when compared with northern regions of the United States, Oklahoma has ...
Identifying traffic safety needs - a systematic approach : [technical summary].
DOT National Transportation Integrated Search
2011-01-01
The Indiana Department of Transportation (INDOT) manages road safety in Indiana through safety emphasis areas, identification of safety needs within these areas, and development and implementation of transportation interventions that address the safe...
Implementation impacts : volume 3, summer 2014.
DOT National Transportation Integrated Search
2014-01-01
Summary of research projects at the Louisiana Transportation Research Center. Projects in this issue include: Edge Lines Reduce the : Number of Crashes on : Rural Two-lane Highways; New Approach Slab Design Decreases Bridge Bumps : in the Road;...
Texas strategic action plan for motorcycles : 2013-2018.
DOT National Transportation Integrated Search
2013-06-01
The Texas Strategic Action Plan for Motorcycles: 2013-2018 provides an integrated : approach to identify implementable strategies and action steps to make the : road environment and infrastructure safer for motorcyclists and other powered : two- and ...
Promoting Health Equity And Eliminating Disparities Through Performance Measurement And Payment.
Anderson, Andrew C; O'Rourke, Erin; Chin, Marshall H; Ponce, Ninez A; Bernheim, Susannah M; Burstin, Helen
2018-03-01
Current approaches to health care quality have failed to reduce health care disparities. Despite dramatic increases in the use of quality measurement and associated payment policies, there has been no notable implementation of measurement strategies to reduce health disparities. The National Quality Forum developed a road map to demonstrate how measurement and associated policies can contribute to eliminating disparities and promote health equity. Specifically, the road map presents a four-part strategy whose components are identifying and prioritizing areas to reduce health disparities, implementing evidence-based interventions to reduce disparities, investing in the development and use of health equity performance measures, and incentivizing the reduction of health disparities and achievement of health equity. To demonstrate how the road map can be applied, we present an example of how measurement and value-based payment can be used to reduce racial disparities in hypertension among African Americans.
Classification of Traffic Related Short Texts to Analyse Road Problems in Urban Areas
NASA Astrophysics Data System (ADS)
Saldana-Perez, A. M. M.; Moreno-Ibarra, M.; Tores-Ruiz, M.
2017-09-01
The Volunteer Geographic Information (VGI) can be used to understand the urban dynamics. In the classification of traffic related short texts to analyze road problems in urban areas, a VGI data analysis is done over a social media's publications, in order to classify traffic events at big cities that modify the movement of vehicles and people through the roads, such as car accidents, traffic and closures. The classification of traffic events described in short texts is done by applying a supervised machine learning algorithm. In the approach users are considered as sensors which describe their surroundings and provide their geographic position at the social network. The posts are treated by a text mining process and classified into five groups. Finally, the classified events are grouped in a data corpus and geo-visualized in the study area, to detect the places with more vehicular problems.
Validating crash locations for quantitative spatial analysis: a GIS-based approach.
Loo, Becky P Y
2006-09-01
In this paper, the spatial variables of the crash database in Hong Kong from 1993 to 2004 are validated. The proposed spatial data validation system makes use of three databases (the crash, road network and district board databases) and relies on GIS to carry out most of the validation steps so that the human resource required for manually checking the accuracy of the spatial data can be enormously reduced. With the GIS-based spatial data validation system, it was found that about 65-80% of the police crash records from 1993 to 2004 had correct road names and district board information. In 2004, the police crash database contained about 12.7% mistakes for road names and 9.7% mistakes for district boards. The situation was broadly comparable to the United Kingdom. However, the results also suggest that safety researchers should carefully validate spatial data in the crash database before scientific analysis.
Geochemical map of the Guadalupe Escarpment Wilderness Study Area, Eddy County, New Mexico
Light, T.D.; Domenico, J.A.; Smith, S.M.
1985-01-01
The Guadalupe Escarpment Wilderness Study Area encompasses approximately 21,300 acres along Guadalupe Ridge in the southern end of the Guadalupe Mountains about 35 miles southwest of Carlsbad, N. Mex. (fig. 1). The area trends northeasterly, is bounded on the south by the Texas State line and the northern boundary of Guadalupe Mountains National Park. The study area is bounded on the northeast by Carlsbad Caverns National Park. The area comprises several narrow, gently sloping mesas bounded by deeply incised canyons. Elevations range from 7,413 feet on Camp Wilderness Ridge to approximately 4,875 feet at Franks Spring. A rough jeep road along the northwest boundary of the study area can be reached by U.S. Forest Service roads from the northwest. The southeastern part of the study area can be approached via unimproved ranch roads leading off U.S. Highway 62-180.
Khazaei, Esmaeil; Milne-Home, William
2017-05-01
Elevated levels of chloride concentration due to anthropogenic activities including the road salts, septic effluent and agricultural sources are common in shallow groundwater of the recent glacial deposits north of Toronto, Ontario, Canada. Identifying suitable techniques for discriminating the source of the chloride concentration helps to better plan the protection of groundwater in the area. This paper examines the applicability of geochemical techniques with emphasis on Panno et al. (Ground Water 44: 176-187, 2006) and Mullaney et al. (2009) graphical approaches for discriminating the sources of chloride with known causes of impacts. The results indicated that the graphical methods developed using Cl - , Br - and/or total nitrogen (N) could identify the combined sources of road salts and septic systems. However, discriminating between the road salts, septic effluent or agricultural sources needs to be complemented by other techniques including the artificial sweeteners and isotope tracers.
Hatton, F; Bouvier, M H; Maujol, L
1981-01-01
Corresponding to a non-experimental approach and based upon the study of indices obtained from permanent statistics, this assessment presents methodological difficulties linked both: to the choice of permanant indicators and to the interpretation of their variations in a situation of observation. The results permit us to appraise the consequences of the global policy of prevention in the field of road traffic accidents in France during many consecutive years: - the decrease of mortality and morbidity demographic indices; - the strengthening of the regressive tendency of the risk indices linked to road traffic (number of dead and wounded in relation to the "km" covered, to the consumption of motor-fuel...). The agreement of the evolutive tendencies of these indicators lets us think that the campaign against traffic accidents has had the desired effects even if they are still incomplete.
NASA Astrophysics Data System (ADS)
Huang, Bo; Hsieh, Chen-Yu; Golnaraghi, Farid; Moallem, Mehrdad
2015-11-01
In this paper a vehicle suspension system with energy harvesting capability is developed, and an analytical methodology for the optimal design of the system is proposed. The optimization technique provides design guidelines for determining the stiffness and damping coefficients aimed at the optimal performance in terms of ride comfort and energy regeneration. The corresponding performance metrics are selected as root-mean-square (RMS) of sprung mass acceleration and expectation of generated power. The actual road roughness is considered as the stochastic excitation defined by ISO 8608:1995 standard road profiles and used in deriving the optimization method. An electronic circuit is proposed to provide variable damping in the real-time based on the optimization rule. A test-bed is utilized and the experiments under different driving conditions are conducted to verify the effectiveness of the proposed method. The test results suggest that the analytical approach is credible in determining the optimality of system performance.
Drawing road networks with focus regions.
Haunert, Jan-Henrik; Sering, Leon
2011-12-01
Mobile users of maps typically need detailed information about their surroundings plus some context information about remote places. In order to avoid that the map partly gets too dense, cartographers have designed mapping functions that enlarge a user-defined focus region--such functions are sometimes called fish-eye projections. The extra map space occupied by the enlarged focus region is compensated by distorting other parts of the map. We argue that, in a map showing a network of roads relevant to the user, distortion should preferably take place in those areas where the network is sparse. Therefore, we do not apply a predefined mapping function. Instead, we consider the road network as a graph whose edges are the road segments. We compute a new spatial mapping with a graph-based optimization approach, minimizing the square sum of distortions at edges. Our optimization method is based on a convex quadratic program (CQP); CQPs can be solved in polynomial time. Important requirements on the output map are expressed as linear inequalities. In particular, we show how to forbid edge crossings. We have implemented our method in a prototype tool. For instances of different sizes, our method generated output maps that were far less distorted than those generated with a predefined fish-eye projection. Future work is needed to automate the selection of roads relevant to the user. Furthermore, we aim at fast heuristics for application in real-time systems. © 2011 IEEE
Italian law on the vehicular homicide: medical legal issues and comparative analysis.
Montanari Vergallo, G; Marinelli, E; di Luca, N M; Masotti, V; Cecchi, R; Zaami, S
2017-01-01
Law no. 41/2016, enacted after a parliamentary debate characterized by a strong media pressure, intends to give a strong response to the growing social alarm caused by road accidents causing deaths. In this perspective, it introduced the categories of road homicide and road injuries within the Penal Code and the new hypotheses of mandatory and facultative arrest in flagrante delicto. This paper aims at comparing the rules by which the United Kingdom, France, Spain, Germany and Italy protect people's lives and safety of vehicular traffic in order to highlight strengths and weaknesses with a view to future reforms. A survey on the European legislature highlights that, while other countries tend to criminally sanction several dangerous driving conducts, Italy has preferred, on the one hand, to punish only with administrative sanctions some violations related to reckless driving (with the exception of driving under the influence of alcohol and drugs) and, on the other, to provide for particularly harsh prison sentences in the case of vehicular homicide. The authors criticize this approach and other aspects of the new law. Moreover, it seems that the legislator's aim has not been achieved because traffic accidents have not decreased. They also believe that better results could be obtained by increasing controls on the roads and developing a policy of economical investments which improves road safety.
Estimation of economic costs of particulate air pollution from road transport in China
NASA Astrophysics Data System (ADS)
Guo, X. R.; Cheng, S. Y.; Chen, D. S.; Zhou, Y.; Wang, H. Y.
2010-09-01
Valuation of health effects of air pollution is becoming a critical component of the performance of cost-benefit analysis of pollution control measures, which provides a basis for setting priorities for action. Beijing has focused on control of transport emission as vehicular emissions have recently become an important source of air pollution, particularly during Olympic games and Post-games. In this paper, we conducted an estimation of health effects and economic cost caused by road transport-related air pollution using an integrated assessment approach which utilizes air quality model, engineering, epidemiology, and economics. The results show that the total economic cost of health impacts due to air pollution contributed from transport in Beijing during 2004-2008 was 272, 297, 310, 323, 298 million US (mean value), respectively. The economic costs of road transport accounted for 0.52, 0.57, 0.60, 0.62, and 0.58% of annual Beijing GDP from 2004 to 2008. Average cost per vehicle and per ton of PM 10 emission from road transport can also be estimated as 106 US /number and 3584 US $ t -1, respectively. These findings illustrate that the impact of road transport contributed particulate air pollution on human health could be substantial in Beijing, whether in physical and economic terms. Therefore, some control measures to reduce transport emissions could lead to considerable economic benefit.
How wide is a road? The association of roads and mass-wasting in a forested montane environment
Larsen, M.C.; Parks, J.E.
1997-01-01
A spatial data base of 1609 landslides was analysed using a geographic information system to determine landslide frequency in relation to highways. A 126 km long transportation network in a 201km2 area of humid-tropical, mountainous, forested terrain in Puerto Rico was used in conjunction with a series of 20 buffer (disturbance) zones varying from 5 to 400m in length, measured perpendicular to the highways. Average landslide frequency in the study area at distances greater than 85m from roads was about six landslides per square kilometre. At distances of 85m or less on either side of a highway, landslide frequency was about 30 landslides per square kilometre. On average, this elevated disturbance rate affected 330m2km-2a-1 within the 170m swath. The mass-wasting rate outside of the disturbance zone affected 40m2km-2 a-1. These results indicate that the rate of mass-wasting disturbance is increased from five to eight times in a 170m wide swath along road corridors. The lateral extent of the environmental impact of roads in the study area is greater than is commonly perceived. The approach described herein demonstrates a simple method to assess the spatial association of mass-wasting with highways. ?? 1997 by John Wiley & Sons, Ltd.
The use of remote sensing and GIS data in the NW Forest Plan aquatic assessment
NASA Astrophysics Data System (ADS)
Hirsch, C.; Gordon, S. N.; Eldred, P.
2017-12-01
The NW Forest Plan is an integrated set of standards and guidelines covering 24 m ac of federal lands on the west side of Washington, Oregon, and northern California. The associated the Aquatic and Riparian Effectiveness Monitoring Program (AREMP) assesses watershed condition and trend on these lands at two levels: upslope/riparian based on GIS and remote sensing data, and inchannel, based on field data collection. AREMP uses a multicriteria evaluation approach similar to WCF, but upslope attributes are restricted to roads and vegetation because these are the only ones which can be reliably backcasted to estimate trend since the start of the Plan in 1994. AREMP has developed a context-sensitive road evaluation system in response to studies showing that a large percentage of road sediment delivery to streams comes from a small percentage of the overall road network, and we are currently testing integration with the GRAIP-lite road sediment tool. AREMP's evaluation of vegetation data, based on Landsat imagery, also uses context derived from the distributions of least-human-disturbed conditions by 16 major forest types. A major question remains in how to evaluate vegetation given the importance of natural disturbances in renewing aquatic habitat. A common challenge across all of our data sources is how to assess uncertainty in data values and locational accuracy.
NASA Astrophysics Data System (ADS)
Yin, Jie; Yu, Dapeng; Yin, Zhane; Liu, Min; He, Qing
2016-06-01
Urban pluvial flood are attracting growing public concern due to rising intense precipitation and increasing consequences. Accurate risk assessment is critical to an efficient urban pluvial flood management, particularly in transportation sector. This paper describes an integrated methodology, which initially makes use of high resolution 2D inundation modeling and flood depth-dependent measure to evaluate the potential impact and risk of pluvial flash flood on road network in the city center of Shanghai, China. Intensity-Duration-Frequency relationships of Shanghai rainstorm and Chicago Design Storm are combined to generate ensemble rainfall scenarios. A hydrodynamic model (FloodMap-HydroInundation2D) is used to simulate overland flow and flood inundation for each scenario. Furthermore, road impact and risk assessment are respectively conducted by a new proposed algorithm and proxy. Results suggest that the flood response is a function of spatio-temporal distribution of precipitation and local characteristics (i.e. drainage and topography), and pluvial flash flood is found to lead to proportionate but nonlinear impact on intra-urban road inundation risk. The approach tested here would provide more detailed flood information for smart management of urban street network and may be applied to other big cities where road flood risk is evolving in the context of climate change and urbanization.
Lenton, Simon; Finlay, Fiona Olwen
2018-01-01
Introduction Cyclists have a high mortality and morbidity per mile travelled compared with car occupants, a figure that is likely to increase if campaigns to increase active travel are successful. Concerns about safety is the leading factor limiting cycling for children. Objective This review brings together a paediatric perspective based on the developmental readiness of children and young people and a public health approach to reducing injuries, to produce a practical agenda for improving the safety of cycling for children. Method Selective literature review. Results While most sports realise the importance of practice and training to create mastery of the game, similar thinking has not been consistently applied to cycling proficiency, so many children do not have an opportunity to master cycling before riding on the roads. Conclusions The aim should be to minimise road traffic injuries involving children and young people in ways that create cobenefits for other members of society, increasing opportunities for active travel, reducing air pollution, creating more green space to play and reducing dependence on motor vehicles. Changes in legislation are required now to enable younger children to cycle on pavements while learning to ride and improvements in road design to separate cyclists from motor vehicles especially routes to school for older children. PMID:29637180
Hybrid Air Quality Modeling Approach For Use in the Near ...
The Near-road EXposures to Urban air pollutant Study (NEXUS) investigated whether children with asthma living in close proximity to major roadways in Detroit, MI, (particularly near roadways with high diesel traffic) have greater health impacts associated with exposure to air pollutants than those living farther away. A major challenge in such health and exposure studies is the lack of information regarding pollutant exposure characterization. Air quality modeling can provide spatially and temporally varying exposure estimates for examining relationships between traffic-related air pollutants and adverse health outcomes. This paper presents a hybrid air quality modeling approach and its application in NEXUS in order to provide spatial and temporally varying exposure estimates and identification of the mobile source contribution to the total pollutant exposure. Model-based exposure metrics, associated with local variations of emissions and meteorology, were estimated using a combination of the AERMOD and R-LINE dispersion models, local emission source information from the National Emissions Inventory, detailed road network locations and traffic activity, and meteorological data from the Detroit City Airport. The regional background contribution was estimated using a combination of the Community Multiscale Air Quality (CMAQ) model and the Space/Time Ordinary Kriging (STOK) model. To capture the near-road pollutant gradients, refined “mini-grids” of model recep
Landslide susceptibility and risk assessment: specificities for road networks
NASA Astrophysics Data System (ADS)
Pellicani, Roberta; Argentiero, Ilenia; Parisi, Alessandro; Spilotro, Giuseppe
2017-04-01
A regional-scale assessment of landslide susceptibility and risk along the main road corridors crossing the provincial territory of Matera (Basilicata Region, Southern Italy) was carried out. The entire provincial road network extends for about 1,320 km through a territory, of which represents the main connection infrastructure among thirty-one municipalities due to the lack of an efficient integrated transportation system through the whole regional territory. For this reason, the strategic importance of these roads consists in their uniqueness in connecting every urban center with the socio-economic surrounding context. These roads and their vehicular traffic are continuously exposed to instability processes (about the 40% of the total length is disrupted by landslides), characterized both by high intensity and low frequency and by low intensity and high frequency. This last typology, consisting in small shallow landslides, is particularly hazardous for the roads since it is widespread along the road network, its occurrence is connected to rainfalls and determines high vulnerability conditions for the road in terms of interruption of vehicular traffic. A GIS-based heuristic-bivariate statistical predictive model was performed to assess and map the landslide susceptibility in the study area, by using a polynomial function of eight predisposing factors, weighted according to their influence on the landslide phenomena, recognized and collected in an inventory. Susceptibility associated to small shallow phenomena was assessed by using a polynomial function of specific factors, such as slope angle and aspect, lithological outcrops, rainfalls, etc. In absence of detailed input data, the spatial distribution of landslide risk along the road corridors was assessed and mapped using a qualitative hazard-consequence matrix approach, by which risk is obtained by combining hazard categories with consequence classes pairwise in a two-dimensional table or matrix. Landslide hazard, which is a function of the return time, due to the lack of temporal data, was evaluated as a function of the landslide intensity (velocity and areal extent) and susceptibility. The direct consequences of instability on the roads were defined by combining exposure and vulnerability in a matrix. Exposure was evaluated in terms of amount of traffic, which was calculated along each road stretch, connecting two or more urban areas, as a function of the average of population of each centers. Vulnerability, which expresses the degree of damage, was assessed in function of the presence of criticalities along roads, which were ranked according to the severity of damages and type of performed reparation works. The consequences, combined with the hazard levels, allowed to assess the landslide risk, classified in low, medium and high levels. The risk map highlighted that about the 30% (392 km) of the examined road corridors is affected by high risk levels. The comparison between the risk map and the landslide inventory recognized along roads has also revealed that the 49.5% of landslides affects sections where the risk was evaluated high. The obtained risk classification of the roads represents a support for decision making and allows to identify the priorities for designing appropriate landslide mitigation plans.
Larue, Grégoire S; Kim, Inhi; Rakotonirainy, Andry; Haworth, Narelle L; Ferreira, Luis
2015-08-01
Improving safety at railway level crossings is an important issue for the Australian transport system. Governments, the rail industry and road organisations have tried a variety of countermeasures for many years to improve railway level crossing safety. New types of intelligent transport system (ITS) interventions are now emerging due to the availability and the affordability of technology. These interventions target both actively and passively protected railway level crossings and attempt to address drivers' errors at railway crossings, which are mainly a failure to detect the crossing or the train and misjudgement of the train approach speed and distance. This study aims to assess the effectiveness of three emerging ITS that the rail industry considers implementing in Australia: a visual in-vehicle ITS, an audio in-vehicle ITS, as well as an on-road flashing beacons intervention. The evaluation was conducted on an advanced driving simulator with 20 participants per trialled technology, each participant driving once without any technology and once with one of the ITS interventions. Every participant drove through a range of active and passive crossings with and without trains approaching. Their speed approach of the crossing, head movements and stopping compliance were measured. Results showed that driver behaviour was changed with the three ITS interventions at passive crossings, while limited effects were found at active crossings, even with reduced visibility. The on-road intervention trialled was unsuccessful in improving driver behaviour; the audio and visual ITS improved driver behaviour when a train was approaching. A trend toward worsening driver behaviour with the visual ITS was observed when no trains were approaching. This trend was not observed for the audio ITS intervention, which appears to be the ITS intervention with the highest potential for improving safety at passive crossings. Copyright © 2015 Elsevier Ltd. All rights reserved.
ERIC Educational Resources Information Center
Connelly, Marie L.; And Others
1996-01-01
Judgments made by four children between seven and nine years of age regarding the safety of crossing a road in front of an approaching vehicle were studied. All participants consistently allowed smaller safety gaps as vehicle speeds increased, and three children often made potentially dangerous decisions at high vehicle speeds. (Author/PB)
Samuel A. Cushman; Jesse S. Lewis; Erin L. Landguth
2014-01-01
There have been few assessments of the performance of alternative resistance surfaces, and little is known about how connectivity modeling approaches differ in their ability to predict organism movements. In this paper, we evaluate the performance of four connectivity modeling approaches applied to two resistance surfaces in predicting the locations of highway...
A Road Map for Learning Progressions Research in Geography
ERIC Educational Resources Information Center
Huynh, Niem Tu; Solem, Michael; Bednarz, Sarah Witham
2015-01-01
This article provides an overview of learning progressions (LP) and assesses the potential of this line of research to improve geography education. It presents the merits and limitations of three of the most common approaches used to conduct LP research and draws on one approach to propose a first draft of a LP on map reading and interpretation.…
Responses of desert bighorn sheep to increased human recreation
Papouchis, C.M.; Singer, F.J.; Sloan, W.B.
2001-01-01
Human recreation has been implicated in the decline of several populations of desert bighorn sheep (Ovis canadensis nelsoni). Managers are concerned about the impact of increased recreation on desert bighorn sheep in Canyonlands National Park (NP), Utah, USA, where visitation increased 325% from 1979 to 1994. We compared behavioral responses of sheep to recreational activity between a low visitor use area and a high visitor use area during 1993 and 1994 by observing behavioral responses, distances moved, and duration of responses to vehicles, mountain bikers, and humans on foot. Hikers caused the most severe responses in desert bighorn sheep (animals fled in 61% of encounters), followed by vehicles (17% fled) and mountain bikers (6% fled), apparently because hikers were more likely to be in unpredictable locations and often directly approached sheep. We observed considerable individual heterogeneity in responses of bighorn sheep to the greater human use: some animals lived close to the road corridor and were apparently habituated to the human activities, but other animals avoided the road corridor. In the high-use area, we observed 3 radiocollared sheep that lived closer to the road than expected and found evidence of fewer responses to vehicles by females in spring, less response time of all sheep to vehicles in spring, and fewer responses to mountain bikers compared to the low-use area. Overall, there was an avoidance of the road corridor by most other bighorn sheep in the high-use area where all animals, on average, were found 39% farther from roads (490 ± 19 m vs. 354 ± 36 m) than in the low-use area. This avoidance of the road corridor by some animals represented 15% less use of potential suitable habitat in the high-use area over the low-use area. Increased sensitivity to hikers in the high-use area was suggested by a greater responsiveness by males in autumn and greater distance fled by females in spring. Responses of bighorn sheep were greater when human activity approached at the same elevation, when sheep were moving or standing, when female interactions occurred in spring and summer and male interactions occurred in autumn, and when sheep were farther from escape terrain. We recommend managers confine hikers to designated trails during spring lambing and the autumn rut in desert bighorn sheep habitat.
Productivity-based approach to valuation of transportation infrastructure.
DOT National Transportation Integrated Search
2014-10-01
Transportation infrastructure, a vital component to sustain economic prosperity, represents the largest public-owned : infrastructure asset in the U.S. With over a trillion invested dollars invested into long-lived physical assets such as : roads and...
Cost effective means to managing pavements in poor condition.
DOT National Transportation Integrated Search
2014-06-01
Tight budgets and dwindling state and federal revenue hinder efforts of transportation agencies to resurrect pavements in poor : condition. As a stop-gap measure, some agencies simply allow roads to deteriorate to gravel. However, this approach...
Identifying traffic safety needs - a systematic approach : research report and user manual.
DOT National Transportation Integrated Search
2012-01-01
The Indiana Department of Transportation (INDOT) manages road safety in Indiana through safety emphasis areas, identification of : safety needs within these areas, and development and implementation of transportation interventions that address the sa...
Driver eye-scanning behavior at intersections at night.
DOT National Transportation Integrated Search
2009-10-01
This research project analyzed drivers eye scanning behavior at night when approaching signalized : and unsignalized intersections using the data from a head-mounted eye-tracking system during open road : driving on a prescribed route. During the ...
Integrated Environmental Modeling: Quantitative Microbial Risk Assessment
The presentation discusses the need for microbial assessments and presents a road map associated with quantitative microbial risk assessments, through an integrated environmental modeling approach. A brief introduction and the strengths of the current knowledge are illustrated. W...
Protect and Restore Lolo Creek Watershed, 2004-2005 Annual Report.
DOE Office of Scientific and Technical Information (OSTI.GOV)
McRoberts, Heidi
2005-12-01
The Nez Perce Tribe Department of Fisheries Resource Management, Watershed Division approaches watershed restoration with a ridge-top to ridge-top approach. Watershed restoration projects within the Lolo Creek watershed are coordinated with the Clearwater National Forest and Potlatch Corporation. The Nez Perce Tribe began watershed restoration projects within the Lolo Creek watershed of the Clearwater River in 1996. Fencing to exclude cattle for stream banks, stream bank stabilization, decommissioning roads, and upgrading culverts are the primary focuses of this project. Riparian enhancement through planting of riparian trees and streambank bioengineering was completed. Culvert inventory was completed in 2004 on US Forestmore » Service and Potlatch Corporation lands in the Lolo Creek drainage. Two high priority culverts were replaced, and are now accessible for fish species. Four miles of road was decommissioned. Tribal crews completed maintenance to the previously built fence.« less
Curvilinear approach to an intersection and visual detection of a collision.
Berthelon, C; Mestre, D
1993-09-01
Visual motion perception plays a fundamental role in vehicle control. Recent studies have shown that the pattern of optical flow resulting from the observer's self-motion through a stable environment is used by the observer to accurately control his or her movements. However, little is known about the perception of another vehicle during self-motion--for instance, when a car driver approaches an intersection with traffic. In a series of experiments using visual simulations of car driving, we show that observers are able to detect the presence of a moving object during self-motion. However, the perception of the other car's trajectory appears to be strongly dependent on environmental factors, such as the presence of a road sign near the intersection or the shape of the road. These results suggest that local and global visual factors determine the perception of a car's trajectory during self-motion.
Upon the reconstruction of accidents triggered by tire explosion. Analytical model and case study
NASA Astrophysics Data System (ADS)
Gaiginschi, L.; Agape, I.; Talif, S.
2017-10-01
Accident Reconstruction is important in the general context of increasing road traffic safety. In the casuistry of traffic accidents, those caused by tire explosions are critical under the severity of consequences, because they are usually happening at high speeds. Consequently, the knowledge of the running speed of the vehicle involved at the time of the tire explosion is essential to elucidate the circumstances of the accident. The paper presents an analytical model for the kinematics of a vehicle which, after the explosion of one of its tires, begins to skid, overturns and rolls. The model consists of two concurent approaches built as applications of the momentum conservation and energy conservation principles, and allows determination of the initial speed of the vehicle involved, by running backwards the sequences of the road event. The authors also aimed to both validate the two distinct analytical approaches by calibrating the calculation algorithms on a case study
Dual Roadside Seismic Sensor for Moving Road Vehicle Detection and Characterization
Wang, Hua; Quan, Wei; Wang, Yinhai; Miller, Gregory R.
2014-01-01
This paper presents a method for using a dual roadside seismic sensor to detect moving vehicles on roadway by installing them on a road shoulder. Seismic signals are split into fixed time intervals in recording. In each interval, the time delay of arrival (TDOA) is estimated using a generalized cross-correlation approach with phase transform (GCC-PHAT). Various kinds of vehicle characterization information, including vehicle speed, axle spacing, detection of both vehicle axles and moving direction, can also be extracted from the collected seismic signals as demonstrated in this paper. The error of both vehicle speed and axle spacing detected by this approach has been shown to be less than 20% through the field tests conducted on an urban street in Seattle. Compared to most existing sensors, this new design of dual seismic sensor is cost effective, easy to install, and effective in gathering information for various traffic management applications. PMID:24526304
Johnson, Marilyn; Oxley, Jennie; Newstead, Stuart; Charlton, Judith
2014-09-01
A key tenet of the safety in numbers theory is that as the number of people cycling increases, more drivers will also be cyclists and therefore will give greater consideration to cyclists when driving. We tested this theory in relation to self-reported behaviour, attitudes and knowledge in relation to cycling. An online survey was conducted of Australian drivers (n=1984) who were also cyclists (cyclist-drivers) and drivers who did not cycle (drivers). Cyclist-drivers were 1.5 times more likely than drivers to report safe driving behaviours related to sharing the roads with cyclists (95% CI: 1.1-1.9, p<0.01). Cyclist-drivers had better knowledge of the road rules related to cycling infrastructure than drivers; however knowledge of road rules related to bike lanes was low for both groups. Drivers were more likely than cyclist-drivers to have negative attitudes (e.g. cyclists are unpredictable and repeatedly overtaking cyclists is frustrating). Findings from this study highlight the need for increased education and awareness in relation to safe driving behaviour, road rules and attitudes towards cyclists. Specific recommendations are made for approaches to improve safety for cyclists. Copyright © 2014. Published by Elsevier Ltd.
Sueur, Cédric; Class, Barbara; Hamm, Charlène; Meyer, Xavier; Pelé, Marie
2013-09-01
When crossing the road, pedestrians have to make a trade-off between saving time and avoiding any risk of injuries. Here, we studied how culture influences an individual's perception of risks when crossing a street, using survival analysis. This study is the first to use this analysis to assess cognitive mechanisms and optimality of decisions underlying road crossing behaviour. We observed pedestrian behaviour in two city centres: Inuyama (Japan) and Strasbourg (France). In each city, observations were made at a safe site consisting of a crosswalk and a street light and at an unsafe site (i.e. no crosswalk or street light). At the unsafe site, we measured the time needed by a pedestrian to take a decision (Tdec). During Tdec, a pedestrian estimates whether he can (Tsafe) or cannot (Trisk) cross the road. Using survival analysis, we studied the distributions of these three time variables and showed that French pedestrians took more risks than Japanese pedestrians, and that males took more risks than females, but only in Japan. More studies would considerably broaden our understanding on how culture may affect decision-making processes under risky circumstances. Copyright © 2013 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
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%.
Sources of hydrocarbons in urban road dust: Identification, quantification and prediction.
Mummullage, Sandya; Egodawatta, Prasanna; Ayoko, Godwin A; Goonetilleke, Ashantha
2016-09-01
Among urban stormwater pollutants, hydrocarbons are a significant environmental concern due to their toxicity and relatively stable chemical structure. This study focused on the identification of hydrocarbon contributing sources to urban road dust and approaches for the quantification of pollutant loads to enhance the design of source control measures. The study confirmed the validity of the use of mathematical techniques of principal component analysis (PCA) and hierarchical cluster analysis (HCA) for source identification and principal component analysis/absolute principal component scores (PCA/APCS) receptor model for pollutant load quantification. Study outcomes identified non-combusted lubrication oils, non-combusted diesel fuels and tyre and asphalt wear as the three most critical urban hydrocarbon sources. The site specific variabilities of contributions from sources were replicated using three mathematical models. The models employed predictor variables of daily traffic volume (DTV), road surface texture depth (TD), slope of the road section (SLP), effective population (EPOP) and effective impervious fraction (EIF), which can be considered as the five governing parameters of pollutant generation, deposition and redistribution. Models were developed such that they can be applicable in determining hydrocarbon contributions from urban sites enabling effective design of source control measures. Copyright © 2016 Elsevier Ltd. All rights reserved.
Warmerdam, Amanda; Newnam, Sharon; Sheppard, Dianne; Griffin, Mark; Stevenson, Mark
2017-08-18
Statistics indicate that employees commuting or traveling as part of their work are overrepresented in workplace injury and death. Despite this, many organizations are unaware of the factors within their organizations that are likely to influence potential reductions in work-related road traffic injury. This article presents a multilevel conceptual framework that identifies health investment as the central feature in reducing work-related road traffic injury. Within this framework, we explore factors operating at the individual driver, workgroup supervisor, and organizational senior management levels that create a mutually reinforcing system of safety. The health investment framework identifies key factors at the senior manager, supervisor, and driver levels to cultivating a safe working environment. These factors are high-performance workplace systems, leader-member exchange and autonomy, trust and empowerment, respectively. The framework demonstrates the important interactions between these factors and how they create a self-sustaining organizational safety system. The framework aims to provide insight into the future development of interventions that are strategically aligned with the organization and target elements that facilitate and enhance driver safety and ultimately reduce work-related road traffic injury and death.
A 3D model for rubber tyres contact, based on Kalker's methods through the STRIPES model
NASA Astrophysics Data System (ADS)
Chollet, Hugues
2012-01-01
A project on the pavement-rutting evolution under the effect of a tram on tyre, led the author to make a link between road and railway approaches to the problem of rolling contact. A simplified model is proposed with a fine description of the contact patch between a tyre and the road, and a more realistic pressure and shear stresses distribution than that available from basic models previously available. Experimental measurements are used to identify some characteristics of the force description, while the geometric shape of the tyre-road section are used, like in the traditional rail-wheel contact models, to build the 3D model. The last part validates a plausible contact pressure shape from self-aligning torque measurements and from Kalker's contact stresses gradient applied to the real tyre used in the project. The final result is a brush model extended from the wheel-rail STRIPES one, applicable to dynamics or contact studies of real tyres, with a physical coupling between longitudinal, lateral and spin effects, and a relatively fine description of the contact stresses along each strip of each tyre of the vehicle on an uneven road.
Wioland, Liên
2013-10-01
Statistics from the French Employee National Health Insurance Fund indicate high accident levels in the transport sector. This study represents initial thinking on a new approach to transport sector prevention based on the assumption that a work situation could be improved by acting on another interconnected work situation. Ergonomic analysis of two connected work situations, involving the road haulage drivers and cross-docking platform employees, was performed to test this assumption. Our results show that drivers are exposed to a number of identified risks, but their multiple tasks raise the question of activity intensification. The conditions, under which the drivers will perform their work and take to the road, are partly determined by the quality and organisation of the platform with which they interact. We make a number of recommendations (e.g. changing handling equipment, re-appraising certain jobs) to improve platform organisation and employee working conditions with the aim of also improving driver conditions. These initial steps in this prevention approach appear promising, but more detailed investigation is required. Copyright © 2013 Elsevier Ltd. All rights reserved.
Where Does Road Salt Go - a Static Salt Model
NASA Astrophysics Data System (ADS)
Yu, C. W.; Liu, F.; Moriarty, V. W.
2017-12-01
Each winter, more than 15 million tons of road salt is applied in the United States for the de-icing purpose. Considerable amount of chloride in road salt flows into streams/drainage systems with the snow melt runoff and spring storms, and eventually goes into ecologically sensitive low-lying areas in the watershed, such as ponds and lakes. In many watersheds in the northern part of US, the chloride level in the water body has increased significantly in the past decades, and continues an upward trend. The environmental and ecological impact of the elevated chloride level can no longer be ignored. However although there are many studies on the biological impact of elevated chloride levels, there are few investigations on how the spatially distributed road salt application affects various parts of the watershed. In this presentation, we propose a static road salt model as a first-order metric to address spacial distribution of salt loading. Derived from the Topological Wetness Index (TWI) in many hydrological models, this static salt model provides a spatial impact as- sessment of road salt applications. To demonstrate the effectiveness of the static model, National Elevation Dataset (NED) of ten-meter resolution of Lake George watershed in New York State is used to generate the TWI, which is used to compute a spatially dis- tributed "salt-loading coefficient" of the whole watershed. Spatially varying salt applica- tion rate is then aggregated, using the salt-loading coefficients as weights, to provide salt loading assessments of streams in the watershed. Time-aggregated data from five CTD (conductivity-temperature-depth) sensors in selected streams are used for calibration. The model outputs and the sensor data demonstrate a strong linear correlation, with the R value of 0.97. The investigation shows that the static modeling approach may provide an effective method for the understanding the input and transport of road salt to within watersheds.
Towards an integrated approach of pedestrian behaviour and exposure.
Papadimitriou, Eleonora
2016-07-01
In this paper, an integrated methodology for the analysis of pedestrian behaviour and exposure is proposed, allowing to identify and quantify the effect of pedestrian behaviour, road and traffic characteristics on pedestrian risk exposure, for each pedestrian and for populations of pedestrians. The paper builds on existing research on pedestrian exposure, namely the Routledge microscopic indicator, proposes adjustments to take into account road, traffic and human factors and extends the use of this indicator on area-wide level. Moreover, this paper uses integrated choice and latent variables (ICLV) models of pedestrian behaviour, taking into account road, traffic and human factors. Finally, a methodology is proposed for the integrated estimation of pedestrian behaviour and exposure on the basis of road, traffic and human factors. The method is tested with data from a field survey in Athens, Greece, which used pedestrian behaviour observations as well as a questionnaire on human factors of pedestrian behaviour. The data were used (i) to develop ICLV models of pedestrian behaviour and (ii) to estimate the behaviour and exposure of pedestrians for different road, traffic and behavioural scenarios. The results suggest that both pedestrian behaviour and exposure are largely defined by a small number of factors: road type, traffic volume and pedestrian risk-taking. The probability for risk-taking behaviour and the related exposure decrease in less demanding road and traffic environments. A synthesis of the results allows to enhance the understanding of the interactions between behaviour and exposure of pedestrians and to identify conditions of increased risk exposure. These conditions include principal urban arterials (where risk-taking behaviour is low but the related exposure is very high) and minor arterials (where risk-taking behaviour is more frequent, and the related exposure is still high). A "paradox" of increased risk-taking behaviour of pedestrians with low exposure is found, suggesting that these pedestrians may partly compensate in moderate traffic conditions due to their increased walking speed. Copyright © 2016 Elsevier Ltd. All rights reserved.
Fast rockfall hazard assessment along a road section using the new LYNX Mobile Mapper Lidar
NASA Astrophysics Data System (ADS)
Dario, Carrea; Celine, Longchamp; Michel, Jaboyedoff; Marc, Choffet; Marc-Henri, Derron; Clement, Michoud; Andrea, Pedrazzini; Dario, Conforti; Michael, Leslar; William, Tompkinson
2010-05-01
The terrestrial laser scanning (TLS) is an active remote sensing technique providing high resolution point clouds of the topography. The high resolution digital elevations models (HRDEM) derived of these point clouds are an important tool for the stability analysis of slopes. The LYNX Mobile Mapper is a new TLS generation developed by Optech. Its particularity is to be mounted on a vehicle and providing a 360° high density point cloud at 200-khz measurement rate in a very short acquisition time. It is composed of two sensors improving the resolution and reducing the laser shadowing. The spatial resolution is better than 10 cm at 10 m range and at a velocity of 50 km/h and the reflectivity of the signal is around 20% at a distance of 200 m. The Lidar is also equipped with a DGPS and an inertial measurement unit (IMU) which gives real time position and georeferences directly the point cloud. Thanks to its ability to provide a continuous data set from an extended area along a road, this TLS system is useful for rockfall hazard assessment. In addition, this new scanner decrease considerably the time spent in the field and the postprocessing is reduced thanks to resultant georeferenced data. Nevertheless, its application is limited to an area close to the road. The LYNX has been tested near Pontarlier (France) along roads sections affected by rockfall. Regarding to the tectonic context, the studied area is located in the Folded Jura mainly composed of limestone. The result is a very detailed point cloud with a point spacing of 4 cm. The LYNX presents detailed topography on which a structural analysis has been carried out using COLTOP-3D. It allows obtaining a full structural description along the road. In addition, kinematic tests coupled with probabilistic analysis give a susceptibility map of the road cut or natural cliffs above the road. Comparisons with field survey confirm the Lidar approach.
Soil-related geohazard assessments for maintaining the UK's minor road network
NASA Astrophysics Data System (ADS)
Pritchard, Oliver; Hallett, Stephen; Farewell, Timothy
2015-04-01
The minor road network of the UK (United Kingdom) encompasses 98% of the overall road network. In recent years the UK's roads have been deteriorating, currently rated 26th in the world and considered at risk and declining by the Institution of Civil Engineers (ICE). Many factors contribute to the degradation and ultimately, to the failure of particular road sections. However, several UK local authorities have identified that during drought conditions, road sections founded upon clay soils which are susceptible to volumetric shrinkage and swelling undergo significant deterioration compared to those sections on non-susceptible soils. Droughts in East Anglia recently resulted in estimated damages of £26 million, leading several local authorities to apply to Central Government for emergency funding. The minor or evolved road network is most at risk due to them having often little, if any, structural foundations. This paper addresses the use of soil-related geohazard assessments and GIS (Geographical Information Systems) in helping to provide a soil-informed maintenance strategy for the asset management of the important (both socially and commercially) local road network of the UK. Furthermore, to establish future subsidence risk, UKCP09 climate projections have been used to model the likely potential soil moisture deficit (PSMD) for baseline (1961-1990), 2030 (2020-2049) and 2050 (2040-2069) scenarios. The incorporation of probabilistic PSMD data into clay-related subsidence models has allowed an assessment of potential subsidence risk, with a range of uncertainties, for these scenarios. Intersection of road networks with future projections of subsidence risk has enabled metrics of potential vulnerability to be established. This will aid prioritisation of areas which require further maintenance to make them more climate resilient, avoiding emergency funding situations. Subsequently, this approach can then be extrapolated to the entire UK minor road network, on a local authority level, to provide a series of regional risk assessments. Case studies are drawn from the UK administrative counties of Lincolnshire and Worcestershire. Data from observed road assessments, obtained from the respective local authorities have been analysed and intersected with clay-related subsidence risk. Lincolnshire County Council have already implemented this research to prioritise approximately £600,000 of road maintenance fund to their minor road network. Further appreciation of the spatial distribution and understanding of soil-related hazards has also led Lincolnshire County Council to trial new resurfacing strategies; these new techniques helping to reduce carbon outputs in the form of materials and transport. A reduction in the amount of potential hazardous (bituminous) waste to landfill is also being achieved through re-inclusion of waste material back into the road foundation where areas are particularly prone to soil shrinkage. Our research shows that soil-related geohazard assessments have a part to play in the asset management of the UK's local highways network. The study supports the ICE's recommendation for a regime which moves towards planned, preventative maintenance and achieving Defra's (Department for Environment, Food and Rural Affairs) aim of a climate resilient UK infrastructure. The methodology introduced here also has applicability to other countries, where appropriate soils and infrastructure data are available.
Twisk, Divera; Commandeur, Jacques J F; Bos, Niels; Shope, Jean T; Kok, Gerjo
2015-01-01
Based on existing literature, a system thinking approach was used to set up a conceptual model on the interrelationships among the components influencing adolescent road mortality, distinguishing between components at the individual level and at the system level. At the individual level the role of risk behaviour (sometimes deliberate and sometimes from inexperience or other non-deliberate causes) in adolescent road mortality is well documented. However, little is known about the extent to which the 'road system' itself may also have an impact on younger adolescents' road mortality. This, by providing a safe or unsafe road environment for all road users (System-induced exposure) and by allowing access to high-risk vehicles at a young or older age through the legal licensing age. This study seeks to explore these relationships by analysing the extent to which the road mortality of 10 to 17 year olds in various jurisdictions can be predicted from the System-induced Exposure (SiE) in a jurisdiction and from its legal licensing age to drive motor vehicles. SiE was operationalized as the number of road fatalities per 10(5) inhabitants/all ages together, but excluding the 10 to 17 year olds. Data on road fatalities during the years 2001 through 2008 were obtained from the OECD International Road Traffic Accident Database (IRTAD) and from the USA NHTSA's Fatality Analysis Reporting System (FARS) database for 29 early and 10 late licensing jurisdictions. Linear mixed models were fitted with annual 'Adolescent road mortality per capita' for 2001 through 2008 as the dependent variable, and time-dependent 'SiE' and time-independent 'Licensing system' as predictor variables. To control for different levels of motorisation, the time-dependent variable 'Annual per capita vehicle distance travelled' was used as a covariate. Licensing system of a jurisdiction was entered as a categorical predictor variable with late licensing countries as a baseline group. The study found support for the protective effects of SiE on adolescent safety. If SiE increased by one unit, the mortality rate of 10 to 17 year olds increased by 0.487 units. No support was found for a protective effect of late licensing for this age group. Thus, compared to young adolescents who are allowed to drive motor vehicles in early licensing jurisdictions, late licensing does not provide extra protection for pre-license adolescents. This finding is probably the result of the high risks associated with alternative transport modes, such as moped riding and bicycling. Also, the fact that the study only included risks to young adolescents themselves and did not include the risks they might pose to other road users and passengers may have contributed to this finding, because such risks are greater when driving a motor vehicle than riding a moped or a bicycle. Therefore, to advance our understanding of the impact of licensing systems, more study is needed into the benefits of early or late licensing, thereby considering these wider effects as well. Copyright © 2014 Elsevier Ltd. All rights reserved.
Effective Social Media Engagement Options for Minnesota’s Diversifying Population
DOT National Transportation Integrated Search
2018-02-02
Minnesota Department of Transportation (MnDOT) and Minnesota Local Road Research Board (LRRB) supported the University of Minnesota to investigate social media options for effective public engagement. A three-part approach assessed 1) the state of so...
Evaluation of deer warning reflectors in Virginia.
DOT National Transportation Integrated Search
2003-01-01
A deer warning reflector consists of a red, double-sided reflector mounted on posts, similar to those used for roadside delineators along roadways. As vehicles approach and move through the road section, it is purported that the reflector reflects th...
5. View looking south from Bronx (east) bank showing masonry ...
5. View looking south from Bronx (east) bank showing masonry approach ramp from Landing (exterior) Street. (Dec. 23, 1988) - University Heights Bridge, Spanning Harlem River at 207th Street & West Harlem Road, New York County, NY
Analysis of Freight Transport Strategies and Methodologies [summary
DOT National Transportation Integrated Search
2017-12-01
Transportation planners constantly examine traffic flows to see if current roadway layouts are serving traffic needs. For freight hauling, this presents one issue on the open road, but a much different issue as these large vehicles approach their des...
NASA Astrophysics Data System (ADS)
Postance, Benjamin; Hillier, John; Dijkstra, Tom; Dixon, Neil
2017-01-01
Disruptions to transportation networks by natural hazard events cause direct losses (e.g. by physical damage) and indirect socio-economic losses via travel delays and decreased transportation efficiency. The severity and spatial distribution of these losses varies according to user travel demands and which links, nodes or infrastructure assets are physically disrupted. Increasing transport network resilience, for example by targeted mitigation strategies, requires the identification of the critical network segments which if disrupted would incur undesirable or unacceptable socio-economic impacts. Here, these impacts are assessed on a national road transportation network by coupling hazard data with a transport network model. This process is illustrated using a case study of landslide hazards on the road network of Scotland. A set of possible landslide-prone road segments is generated using landslide susceptibility data. The results indicate that at least 152 road segments are susceptible to landslides, which could cause indirect economic losses exceeding £35 k for each day of closure. In addition, previous estimates for historic landslide events might be significant underestimates. For example, the estimated losses for the 2007 A83 ‘Rest and Be Thankful’ landslide are £80 k day-1, totalling £1.2 million over a 15 day closure, and are ˜60% greater than previous estimates. The spatial distribution of impact to road users is communicated in terms of ‘extended hazard impact footprints’. These footprints reveal previously unknown exposed communities and unanticipated spatial patterns of severe disruption. Beyond cost-benefit analyses for landslide mitigation efforts, the approach implemented is applicable to other natural hazards (e.g. flooding), combinations of hazards, or even other network disruption events.
NASA Astrophysics Data System (ADS)
Naulin, J.-P.; Payrastre, O.; Gaume, E.
2013-04-01
SummaryAccurate flood forecasts are critical to an efficient flood event management strategy. Until now, hydro-meteorological forecasts have mainly been used to establish early-warnings in France (meteorological and flood vigilance maps) or over the world (flash-flood guidances). These forecasts are typically limited either to the main streams covered by the flood forecasting services or to watersheds with specific assets like check dams, which in most cases are well gauged river sections, thus leaving aside large parts of the territory. This paper presents a distributed hydro-meteorological forecasting approach, which makes use of the high spatial and temporal resolution rainfall estimates that are now available, to provide information at ungauged sites. The proposed system intended to detect road inundation risks had initially been developed and tested in areas of limited size. This paper presents the extension of such a system to an entire region (i.e. the Gard region in Southern France), including over 2000 crossing points between rivers and roads and its validation with respect to a large data set of actual reported road inundations observed during recent flash flood events. These initial validation results appear to be most promising. The eventual proposed tool would provide the necessary information for flood event management services to identify the areas at risk and adopt appropriate safety and rescue measures: i.e. pre-positioning of rescue equipment, interruption of the traffic on the exposed roads and determination of safe access or evacuation routes. Moreover, beyond the specific application to the supervision of a road network, the research undertaken herein also provides results for the performance of hydro-meteorological forecasts on ungauged headwaters.
Detecting New Pedestrian Facilities from VGI Data Sources
NASA Astrophysics Data System (ADS)
Zhong, S.; Xie, Z.
2017-12-01
Pedestrian facility (e.g. footbridge, pedestrian crossing and underground passage) information is an important basic data of location based service (LBS) for pedestrians. However, timely updating pedestrian facility information challenges due to facilities change frequently. Previous pedestrian facility information collecting and updating tasks are mainly completed by highly trained specialized persons. However, this conventional approach has several disadvantages such as high cost, long update cycle and so on. Volunteered Geographic Information (VGI) has proven efficiency to provide new, free and fast growing spatial data. Pedestrian trajectory, which can be seen as measurements of real pedestrian road, is one of the most valuable information of VGI data. Although the accuracy of the trajectories is not too high, due to the large number of measurements, an improvement of quality of the road information can be achieved. Thus, we develop a method for detecting new pedestrian facilities based on the current road network and pedestrian trajectories. Specifically, 1) by analyzing speed, distance and direction, those outliers of pedestrian trajectories are removed, 2) a road network matching algorithm is developed for eliminating redundant trajectories, and 3) a space-time cluster algorithm is adopted for detecting new walking facilities. The performance of the method is evaluated with a series of experiments conducted on a part of the road network of Heifei and a large number of real pedestrian trajectories, and verified the results by using Tencent Street map. The results show that the proposed method is able to detecting new pedestrian facilities from VGI data accurately. We believe that the proposed method provides an alternative way for general road data acquisition, and can improve the quality of LBS for pedestrians.
Kimberlee, Richard
2008-05-01
This paper reports on Birmingham City Council's Streets Ahead on Safety project which aims to improve road safety and quality of life in an area of multiple deprivation where 87 000 people from largely Asian, immigrant backgrounds live. A third of residents are under 16 years old and 58% self-define their religion as Muslim. The area has a poor traffic accident record leading to high levels of killed or seriously injured children. Child accidental injury in Europe is reaching 'epidemic' proportions, requiring innovative, ameliorative approaches to redress. Existing UK school-based road safety initiatives rarely extend beyond the 'tokenistic', but this project endeavoured to encourage a highway authority, engineers and road safety officers to provide local young people with opportunities to participate in decision-making in the belief that the active engagement of young service users would lead to more effective and sustainable solutions to accident prevention. Embracing the city's ratification of the UN Convention on the Rights of the Child (1989), this project promoted young people's participation in decision-making around engineering plans for their local community. The project included 405 young people aged 9-11 years who conducted environmental audits, interactive road safety awareness and citizenship training, and engaged as decision-makers. Successful outcomes include increased knowledge of road and community safety issues, and the establishment of young people as stakeholders in the development of their own safety and active engagement with service providers in the development of engineering proposals. This paper highlights the potential dynamics of participation and the dilemmas it poses for relationships between service users and providers, and outlines some of the barriers confronted by young people in learning to be active participants.
NASA Astrophysics Data System (ADS)
Mieczkowski, P.; Budziński, B.
2018-05-01
When well performed, pavement renewal or alteration shall ensure the desired properties of the road during the assumed period of operation. Presence of water in the subgrade can be one of the main factors affecting the structural capacity of pavement and can result in cracking of the bituminous layers, even after a very short period of trafficking. Reconstruction of one of regional roads in Poland has been chosen to serve as an example of inappropriate approach to the problem of the presence of water in the road structure. The project included construction of new layers of pavement and increasing the design life of the whole pavement structure to 4.06 million ESAL of 100 kN (as per the Standard Catalogue of Typical Flexible and Semi-rigid Road Pavement Structures, issue of 1997). After a relatively short period of trafficking (3-5 years) localised alligator cracking appeared on the surface along with structural deformations. The pavement condition assessment including FWD tests was carried out to reveal excessive deflections (over 500 μm) which classify the road for renewal. The analysis of data showed that the main cause of distress was softening of the subgrade caused by an ingress of precipitation water under the pavement layers through the roadway and shoulder edges. The deficiencies of the performed reconstruction occurred both in the roadway (including small step-outs in the cement-treated layer) and partly in the shoulders where the existing soil was in places replaced with impervious material, with the existing (cohesive) material left in place on a major part of the overall length.
NASA Astrophysics Data System (ADS)
Kirshen, P. H.; Knott, J. F.; Ray, P.; Elshaer, M.; Daniel, J.; Jacobs, J. M.
2016-12-01
Transportation climate change vulnerability and adaptation studies have primarily focused on surface-water flooding from sea-level rise (SLR); little attention has been given to the effects of climate change and SLR on groundwater and subsequent impacts on the unbound foundation layers of coastal-road infrastructure. The magnitude of service-life reduction depends on the height of the groundwater in the unbound pavement materials, the pavement structure itself, and the loading. Using a steady-state groundwater model, and a multi-layer elastic pavement evaluation model, the strain changes in the layers can be determined as a function of parameter values and the strain changes translated into failure as measured by number of loading cycles to failure. For a section of a major coastal road in New Hampshire, future changes in sea-level, precipitation, temperature, land use, and groundwater pumping are characterized by deep uncertainty. Parameters that describe the groundwater system such as hydraulic conductivity can be probabilistically described while road characteristics are assumed to be deterministic. To understand the vulnerability of this road section, a bottom-up planning approach was employed over time where the combinations of parameter values that cause failure were determined and their plausibility of their occurring was analyzed. To design a robust adaptation strategy that will function reasonably well in the present and the future given the large number of uncertain parameter values, performance of adaptation options were investigated. Adaptation strategies that were considered include raising the road, load restrictions, increasing pavement layer thicknesses, replacing moisture-sensitive materials with materials that are not moisture sensitive, improving drainage systems, and treatment of the underlying materials.
Pedersen, Marie; Garne, Ester; Hansen-Nord, Nete; Hjortebjerg, Dorrit; Ketzel, Matthias; Raaschou-Nielsen, Ole; Nybo Andersen, Anne-Marie; Sørensen, Mette
2017-11-01
Ambient air pollution has been associated with certain congenital anomalies, but few studies rely on assessment of fine-scale variation in air quality and associations with noise from road traffic are unexplored. Among 84,218 liveborn singletons (1997-2002) from the Danish National Birth Cohort with complete covariate data and residential address history from conception until birth, we identified major congenital anomalies in 4018 children. Nitrogen dioxide (NO 2 ) and noise from road traffic (L den ) burden during fetal life was modeled. Outcome and covariate data were derived from registries, hospital records and questionnaires. Odds ratios (ORs) for eleven major anomaly groups associated with road traffic pollution during first trimester were estimated using logistic regression with generalized estimating equation (GEE) approach. Most of the associations tested did not suggest increased risks. A 10-µg/m 3 increase in NO 2 exposure during first trimester was associated with an adjusted ORs of 1.22 (95% confidence interval: 0.98-1.52) for ear, face and neck anomalies; 1.14 0.98-1.33) for urinary anomalies. A 10-dB increase in road traffic noise was also associated with these subgroups of anomalies as well as with an increased OR for orofacial cleft anomalies (1.17, 0.94-1.47). Inverse associations for several both air pollution and noise were observed for atrial septal defects (0.85, 0.68-1.04 and 0.81, 0.65-0.99, respectively). Residential road traffic exposure to noise or air pollution during pregnancy did not seem to pose a risk for development of congenital anomalies. Copyright © 2017 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Ramos-Scharron, C. E.; LaFevor, M. C.; Roy, J.
2017-12-01
Developing a conceptually sound yet practical understanding of runoff and sediment delivery from human occupied lands to tropical ocean waters still represents a pivotal need of coral reef management worldwide. In the dry tropical and ephemeral streamflow setting that typifies the small watersheds ( 1s km2) draining the US Virgin Islands, changes in hydrologic and sediment delivery dynamics provoked by unsurfaced road networks represent a major threat to coral reefs and other sensitive marine ecosystems. Through a combined empirical and modeling approach, this study evaluates how road building and associated stormflow restoration strategies affect rainfall thresholds for runoff generation at varying spatial scales and their impact on land-to-sea connectivity. Rainfall thresholds and runoff coefficients for precipitation excess on unpaved roads are 2-3 mm and 22-30% (respectively) or a full order of magnitude different from those for undisturbed hillslopes and watersheds. Here we discuss the use of a `volume-to-breakthrough' inspired index to predict the potential of road runoff to reach downslope portions of the watershed and the coastline as runon. The index integrates the effects of storm-by-storm runoff accumulation for every road drainage point with its flow distance to specific locations along the stream network. While large runoff volumes and short flow distances imply a relatively high connectivity potential, small volumes and long distances are associated to low delivery potential. The index has proven able to discern observed runoff responses under a variety of road-stream network scenarios and rainfall conditions. These results enhance our understanding of ephemeral stream hydrology and are serving to improve coral reef management strategies throughout the Northeastern Caribbean.
An Approach Toward Understanding Wildlife-Vehicle Collisions
NASA Astrophysics Data System (ADS)
Litvaitis, John A.; Tash, Jeffrey P.
2008-10-01
Among the most conspicuous environmental effects of roads are vehicle-related mortalities of wildlife. Research to understand the factors that contribute to wildlife-vehicle collisions can be partitioned into several major themes, including (i) characteristics associated with roadkill hot spots, (ii) identification of road-density thresholds that limit wildlife populations, and (iii) species-specific models of vehicle collision rates that incorporate information on roads (e.g., proximity, width, and traffic volume) and animal movements. We suggest that collision models offer substantial opportunities to understand the effects of roads on a diverse suite of species. We conducted simulations using collision models and information on Blanding’s turtles ( Emydoidea blandingii), bobcats ( Lynx rufus), and moose ( Alces alces), species endemic to the northeastern United States that are of particular concern relative to collisions with vehicles. Results revealed important species-specific differences, with traffic volume and rate of movement by candidate species having the greatest influence on collision rates. We recommend that future efforts to reduce wildlife-vehicle collisions be more proactive and suggest the following protocol. For species that pose hazards to drivers (e.g., ungulates), identify collision hot spots and implement suitable mitigation to redirect animal movements (e.g., underpasses, fencing, and habitat modification), reduce populations of problematic game species via hunting, or modify driver behavior (e.g., dynamic signage that warns drivers when animals are near roads). Next, identify those species that are likely to experience additive (as opposed to compensatory) mortality from vehicle collisions and rank them according to vulnerability to extirpation. Then combine information on the distribution of at-risk species with information on existing road networks to identify areas where immediate actions are warranted.
Evaluation of mobile source emission trends in the United States
NASA Astrophysics Data System (ADS)
Dallmann, Timothy R.; Harley, Robert A.
2010-07-01
A fuel-based approach is used to estimate exhaust emissions of nitrogen oxides (NOx) and fine particulate matter (PM2.5) from mobile sources in the United States for the years 1996-2006. Source categories considered include on-road and off-road gasoline and diesel engines. Pollutant emissions for each mobile source category were estimated by combining fuel consumption with emission factors expressed per unit of fuel burned. Over the 10-year time period that is the focus of this study, sales of gasoline and diesel fuel intended for on-road use increased by 15 and 43%, respectively. Diesel fuel use by off-road equipment increased by ˜20% over the same time period. Growth in fuel consumption offset some of the reductions in pollutant emission factors that occurred during this period. For NOx, there have been dramatic (factor of 2) decreases in emission factors for on-road gasoline engines between 1996 and 2006. In contrast, diesel NOx emission factors decreased more gradually. Exhaust PM2.5 emission factors appear to have decreased for most engine categories, but emission uncertainties are large for this pollutant. Diesel engines appear to be the dominant mobile source of both NOx and PM2.5; the diesel share of total NOx has increased over time as gasoline engine emissions have declined. Comparing fuel-based emission estimates with U.S. Environmental Protection Agency's national emission inventory led to the following conclusions: (1) total emissions of NOx and PM2.5 estimated by two different methods were similar, (2) source contributions to these totals differ significantly, with higher relative contributions coming from on-road diesel engines in this study.
Heavy metals in garden soils along roads in Szeged, Hungary
NASA Astrophysics Data System (ADS)
Szolnoki, Zsuzsanna; Farsang, Andrea
2010-05-01
The soils of the urban environment, owing to the various anthropogenic activities, can be contaminated by heavy metals. The traffic is well-known for more decades to be main source of heavy metals mostly in cities. The accumulation of these elements can have different effects, either directly endangering the natural soil functions, or indirectly endangering the biosphere by bio-accumulation and inclusion in the food chain. The hobby gardens and the vegetable gardens directly along roads can be potential risky for people since unknown amount of heavy metals can be accumulated into organization of local residents due to consumption of vegetables and fruits grown in their own garden. The aim of this study was to determine the heavy metal content of garden soils directly along roads with heavy traffic in order to assess possible risk for human health. The total content and the mobile content of Cd, Co, Cr, Cu, Ni, Pb and Zn have been determined in samples from garden soils along 5 busy roads of Szeged, South Hungary. Enrichment factor has been calculated with the help of control soil samples far from roads. The soil properties basically influencing on metal mobility have also been examined. Finally, the human health risk of these garden soils has been modelled by determination of health risk quotient (HRQ). As a result of our investigations, it can be claimed that mostly Cu, Zn and to a lesser degree the Ni, Cr and Pb accumulated in garden soils along roads depending on the traffic density. In general, the topsoils (0-10 cm) had higher amount of these metals rather than the subsoils (40-50 cm). Ni of these metals has approached; Cu has exceeded limit value while Pb is under it. Cd is very high in both soils along roads and control ones far from roads. Garden soils along the roads have such basic soil parameters (pH, mechanical soil type, humus content) that prove fairly high metal-binding capacity for these soils. Total risk of usage of these gardens (ingestion of soil, dermal contact, consumption of vegetables) has not exceeded the moderate level in normal case. However, the degree of risk has considerably increased if you consume exclusively vegetables in contaminated garden soils. In this case the risk can be relatively high for the more sensitive children.
Effectiveness of transverse grooves in rigid pavement
NASA Astrophysics Data System (ADS)
Gurney, G. F.; Bryden, J. E.
1982-10-01
Transverse grooves were installed at 11 intersection approaches on worn rigid pavement to reduce a high rate of wet road accidents. In most cases, accident reductions were experienced only at intersections with multiple negative operational characteristics, including higher approach speeds, limited sight distances, and frequent vehicle stopping for turns or stop signs. Intersections with no more than one negative characteristic generally did not benefit from grooving.
Navigations: The Road to a Better Orientation.
Rizzo, Leah Heather
2016-01-01
A team of nursing professional development specialists from a large Magnet® healthcare network transformed new employee orientation using a themed, interdisciplinary, learner-centered approach. Guided by project management principles, the nursing professional development team created an engaging program that serves as an interactive guide for new hires' orientation journey. This unique approach differs from traditional orientation programs through its incorporation of gaming, video clips, and group discussions.
ERIC Educational Resources Information Center
Roets, Griet; Goedgeluck, Marijke
2007-01-01
In this article, the authors trace the possible political potential of their post-modernist, feminist approach to life story research with people with the label of "learning difficulties." As a self-advocate with an ally, they define tagging along with each other as discovery science. The authors reflect on how they openly and critically write…
Driving and Dementia: A Review of the Literature
Brown, Laura B.; Ott, Brian R.
2012-01-01
The purpose of this article is to review the literature on the ability of individuals with dementia to drive an automobile. Based on a review of the literature, several factors were identified that may be useful in differentiating between people with dementia who presently remain safe drivers from those who have progressed to impaired driving. These factors include disease duration and severity, sex, patient self-assessment, family assessment, neuropsychological measures, findings on road evaluations, and driving simulator testing. The approach of the physician to driving and dementia is addressed, including in-office screening, referral for on-road driving assessments, and the potential for physician reporting to state agencies. PMID:15533995
NASA Astrophysics Data System (ADS)
Mendes Godinho, R.; Raimundo, J.; Vale, C.; Anes, B.; Brito, P.; Alves, L. C.; Pinheiro, T.
2013-07-01
In the scope of a monitoring program to assess the environmental impact of automobile traffic over one main bridge in Lisbon, both water and duckweed (Lemna minor L.) were sampled from the road drainage tanks and analyzed for chemical elements. Plants uptake Cr, Mn, Cu, and Zn metals from rain water draining the bridge road. Nuclear microprobe elemental maps of cryosections of L. minor tissues showed that incorporated elements were internalized in fronds of the plant. This approach at micrometer level allows a better knowledge of the elemental tissue partitioning in this biomonitor organism.
Daytime Water Detection by Fusing Multiple Cues for Autonomous Off-Road Navigation
NASA Technical Reports Server (NTRS)
Rankin, A. L.; Matthies, L. H.; Huertas, A.
2004-01-01
Detecting water hazards is a significant challenge to unmanned ground vehicle autonomous off-road navigation. This paper focuses on detecting the presence of water during the daytime using color cameras. A multi-cue approach is taken. Evidence of the presence of water is generated from color, texture, and the detection of reflections in stereo range data. A rule base for fusing water cues was developed by evaluating detection results from an extensive archive of data collection imagery containing water. This software has been implemented into a run-time passive perception subsystem and tested thus far under Linux on a Pentium based processor.
Sazzini, Marco; Garagnani, Paolo; Sarno, Stefania; De Fanti, Sara; Lazzano, Teresa; Yang Yao, Daniele; Boattini, Alessio; Pazzola, Giulia; Maramotti, Sally; Boiardi, Luigi; Franceschi, Claudio; Salvarani, Carlo; Luiselli, Donata
2015-01-01
Behçet's disease is a multifactorial vasculitis that shows its highest prevalence in geographical areas historically involved in the Silk Road, suggesting that it might have originated somewhere along these ancient trade routes. This study aims to provide a first clue towards genetic evidence for this hypothesis by testing it via an anthropological evolutionary genetics approach. Behçet's disease variation at ancestry informative mitochondrial DNA control region and haplogroup diagnostic sites was characterised in 185 disease subjects of Italian descent and set into the Eurasian mitochondrial landscape by comparison with nearly 9,000 sequences representative of diversity observable in Italy and along the main Silk Road routes. Dissection of the actual genetic ancestry of disease individuals by means of population structure, spatial autocorrelation and haplogroup analyses revealed their closer relationships with some Middle Eastern and Central Asian groups settled along the Silk Road than with healthy Italians. These findings support the hypothesis that the Behçet's disease genetic risk has migrated to western Eurasia in parallel with ancestry components typical of Silk Road-related groups. This provided new insights that are useful to improve the understanding of disease origins and diffusion, as well as to inform future association studies aimed at properly accounting for the actual genetic ancestry of the examined Behçet's disease samples in order to minimise the detection of spurious associations and to improve the identification of genetic variants with actual clinical relevance.
Morelli, Federico
2017-01-01
Road and railway networks are pervasive elements of all environments, which have expanded intensively over the last century in all European countries. These transportation infrastructures have major impacts on the surrounding landscape, representing a threat to biodiversity. Roadsides and railways may function as corridors for dispersal of alien species in fragmented landscapes. However, only few studies have explored the spread of invasive species in relationship to transport network at large spatial scales. We performed a spatial mismatch analysis, based on a spatially explicit correlation test, to investigate whether alien plant species hotspots in Germany and Austria correspond to areas of high density of roads and railways. We tested this independently of the effects of dominant environments in each spatial unit, in order to focus just on the correlation between occurrence of alien species and density of linear transportation infrastructures. We found a significant spatial association between alien plant species hotspots distribution and roads and railways density in both countries. As expected, anthropogenic landscapes, such as urban areas, harbored more alien plant species, followed by water bodies. However, our findings suggested that the distribution of neobiota is strongest correlated to road/railways density than to land use composition. This study provides new evidence, from a transnational scale, that alien plants can use roadsides and rail networks as colonization corridors. Furthermore, our approach contributes to the understanding on alien plant species distribution at large spatial scale by the combination with spatial modeling procedures. PMID:28829818
Su, Shiliang; Xiao, Rui; Li, Delong; Hu, Yi'na
2014-03-01
A comparison of different transportation route types and their combined effects on landscape diversity was conducted within Tiaoxi watershed (China) between 1994 and 2005. Buffer analysis and Mann-Kendall's test were used to quantify the relationships between distance from transportation routes (railway, highway, national, and provincial road) and a family of landscape diversity parameters (Simpson's diversity index, Simpson's evenness index, Shannon's diversity index, and Shannon's evenness index). One-way ANOVA was further applied to compare influences from different route types and their combined effects. Five other landscape metrics (patch density, edge density, area-weighted mean shape index, connectance index, and Euclidean nearest neighbor distance) were also calculated to analyze the associations between landscape diversity and landscape pattern characteristics. Results showed that transportation routes exerted significant impacts on landscape diversity. Impact from railway was comparable to that from highway and national road but was more significant than that from provincial road. The spatial influential range of railway and national road was wider than that of highway and provincial road. Combined effects of routes were nonlinear, and impacts from different route types were more complex than those from the same type. The four landscape diversity metrics were comparably effective at the buffer zone scale. In addition, landscape diversity can be alternatively used to indicate fragmentation, connectivity, and isolation at route buffer scale. This study demonstrates an applicable approach to quantitatively characterize the impacts from transportation routes on landscape patterns and has potential to facilitate route network planning.
Putting Up a Big Front: Car Design and Size Affect Road-Crossing Behaviour
Klatt, Wilhelm K.; Chesham, Alvin; Lobmaier, Janek S.
2016-01-01
Previous research suggests that people tend to see faces in car fronts and that they attribute personality characteristics to car faces. In the present study we investigated whether car design influences pedestrian road-crossing behaviour. An immersive virtual reality environment with a zebra crossing scenario was used to determine a) whether the minimum accepted distance for crossing the street is larger for cars with a dominant appearance than for cars with a friendly appearance and b) whether the speed of dominant-looking cars is overestimated as compared to friendly-looking cars. Participants completed both tasks while either standing on the pavement or on the centre island. We found that people started to cross the road later in front of friendly-looking low-power cars compared to dominant-looking high-power cars, but only if the cars were relatively large in size. For small cars we found no effect of power. The speed of smaller cars was estimated to be higher compared to large cars (size-speed bias). Furthermore, there was an effect of starting position: From the centre island, participants entered the road significantly later (i. e. closer to the approaching car) and left the road later than when starting from the pavement. Similarly, the speed of the cars was estimated significantly lower when standing on the centre island compared to the pavement. To our knowledge, this is the first study to show that car fronts elicit responses on a behavioural level. PMID:27434187
Using GPS telemetry to determine roadways most susceptible to deer-vehicle collisions
Kramer, David W.; Prebyl, Thomas J.; Stickles, James H.; Osborn, David A.; Irwin, Brian J.; Nibbelink, Nathan P.; Warren, Robert J.; Miller, Karl V.
2016-01-01
More than 1 million wildlife-vehicle collisions occur annually in the United States. The majority of these accidents involve white-tailed deer (Odocoileus virginianus) and result in >US $4.6 billion in damage and >200 human fatalities. Prior research has used collision locations to assess sitespecific as well as landscape features that contribute to risk of deer-vehicle collisions. As an alternative approach, we calculated road-crossing locations from 25 GPS-instrumented white-tailed deer near Madison, Georgia (n=154,131 hourly locations). We identified crossing locations by creating movement paths between subsequent GPS points and then intersecting the paths with road locations. Using AIC model selection, we determined whether 10 local and landscape variables were successful at identifying areas where higher frequencies of deer crossings were likely to occur. Our findings indicate that traffic volume, distance to riparian areas, and the amount of forested area influenced the frequency of road crossings. Roadways that were predominately located in wooded landscapes and 200–300 m from riparian areas were crossed frequently. Additionally, we found that areas of low traffic volume (e.g., county roads) had the highest frequencies of deer crossings. Analyses utilizing only records of deer-vehicle collision locations cannot separate the relative contribution of deer crossing rates and traffic volume. Increased frequency of road crossings by deer in low-traffic, forested areas may lead to a greater risk of deer-vehicle collision than suggested by evaluations of deer-vehicle collision frequency alone.
Putting Up a Big Front: Car Design and Size Affect Road-Crossing Behaviour.
Klatt, Wilhelm K; Chesham, Alvin; Lobmaier, Janek S
2016-01-01
Previous research suggests that people tend to see faces in car fronts and that they attribute personality characteristics to car faces. In the present study we investigated whether car design influences pedestrian road-crossing behaviour. An immersive virtual reality environment with a zebra crossing scenario was used to determine a) whether the minimum accepted distance for crossing the street is larger for cars with a dominant appearance than for cars with a friendly appearance and b) whether the speed of dominant-looking cars is overestimated as compared to friendly-looking cars. Participants completed both tasks while either standing on the pavement or on the centre island. We found that people started to cross the road later in front of friendly-looking low-power cars compared to dominant-looking high-power cars, but only if the cars were relatively large in size. For small cars we found no effect of power. The speed of smaller cars was estimated to be higher compared to large cars (size-speed bias). Furthermore, there was an effect of starting position: From the centre island, participants entered the road significantly later (i. e. closer to the approaching car) and left the road later than when starting from the pavement. Similarly, the speed of the cars was estimated significantly lower when standing on the centre island compared to the pavement. To our knowledge, this is the first study to show that car fronts elicit responses on a behavioural level.
Agricultural vehicles and rural road safety: tackling a persistent problem.
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 these accident factors. For AV drivers, a driver's training focusing on driving behavior in the presence of vulnerable road users and concluding with an examination is advised. For vehicle safety, actual practice in The Netherlands is inadequate for control of proper maintenance. Some permanent requirements for the AV are insufficiently specific (view) or effective (lighting) and too generous (width). For infrastructure, a wide range of measures is available. A targeted approach to all road system components is urgently needed to avoid a further worsening of existing problems and to reduce the above proportional role of AVs in road danger. Supplemental materials are available for this article. Go to the publisher's online edition of Traffic Injury Prevention to view the supplemental file.
Size and Placement of Metal Culverts Critical on Peatland Woods Roads
J.H. Stoeckeler
1967-01-01
Culverts too small in diameter or poorly placed were major causes of timber flooding and tree damage. Placement problems were poor culvert slope, poor hydraulic approach, lack of gravel bedding, and too little soil covering the culverts.
DOT National Transportation Integrated Search
2012-06-01
A small team of university-based transportation system experts and simulation experts has been : assembled to develop, test, and apply an approach to assessing road infrastructure capacity using : micro traffic simulation supported by publically avai...
Travel importance and strategic investment in Vermont's transportation assets.
DOT National Transportation Integrated Search
2013-12-01
This project advances a new type of system-wide measurement of link criticality : that will provide the tools needed for strategic disinvestment in roads that are not : critical to the health and welfare of Vermonters. This new approach requires a : ...
Novel approaches for road congestion mitigation.
DOT National Transportation Integrated Search
2012-07-02
Transportation planning is usually aiming to solve two problems: the traffic assignment and the toll pricing problems. The latter one utilizes information from the first one, in order to find the optimal set of tolls that is the set of tolls that lea...
Novel approaches for road congestion minimization.
DOT National Transportation Integrated Search
2012-07-01
Transportation planning is usually aiming to solve two problems: the traffic assignment and the toll pricing problems. The latter one utilizes information from the first one, in order to find the optimal set of tolls that is the set of tolls that lea...
Uncertainties in Emissions In Emissions Inputs for Near-Road Assessments
Emissions, travel demand, and dispersion models are all needed to obtain temporally and spatially resolved pollutant concentrations. Current methodology combines these three models in a bottom-up approach based on hourly traffic and emissions estimates, and hourly dispersion conc...
Guardrail and bridge rail recommendations for very low-volume local roads in Kansas.
DOT National Transportation Integrated Search
2014-12-01
The determination of warrants for bridge railing and approach guardrails is a fundamental roadside safety issue. These are : specialized roadside safety barriers that are intended to capture and smoothly redirect errant vehicles that leave the roadwa...
Developing an Interactive Machine-Learning-based Approach for Sidewalk Digitalization
DOT National Transportation Integrated Search
2018-01-01
In urban areas, many socio-economic concerns have been raised regarding fatal collisions, traffic congestion, and deteriorated air quality due to increased travel and logistic demands as well as the existing on-road transportation systems. As one of ...
Non-reciprocity and topology in optics: one-way road for light via surface magnon polariton.
Ochiai, Tetsuyuki
2015-02-01
We show how non-reciprocity and topology are used to construct an optical one-way waveguide in the Voigt geometry. First, we present a traditional approach of the one-way waveguide of light using surface polaritons under a static magnetic field. Second, we explain a recent discovery of a topological approach using photonic crystals with the magneto-optical coupling. Third, we present a combination of the two approaches, toward a broadband one-way waveguide in the microwave range.
Non-reciprocity and topology in optics: one-way road for light via surface magnon polariton
Ochiai, Tetsuyuki
2015-01-01
We show how non-reciprocity and topology are used to construct an optical one-way waveguide in the Voigt geometry. First, we present a traditional approach of the one-way waveguide of light using surface polaritons under a static magnetic field. Second, we explain a recent discovery of a topological approach using photonic crystals with the magneto-optical coupling. Third, we present a combination of the two approaches, toward a broadband one-way waveguide in the microwave range. PMID:27877739
Identifying the most significant indicators of the total road safety performance index.
Tešić, Milan; Hermans, Elke; Lipovac, Krsto; Pešić, Dalibor
2018-04-01
The review of the national and international literature dealing with the assessment of the road safety level has shown great efforts of the authors who tried to define the methodology for calculating the composite road safety index on a territory (region, state, etc.). The procedure for obtaining a road safety composite index of an area has been largely harmonized. The question that has not been fully resolved yet concerns the selection of indicators. There is a wide range of road safety indicators used to show a road safety situation on a territory. Road safety performance index (RSPI) obtained on the basis of a larger number of safety performance indicators (SPIs) enable decision makers to more precisely define the earlier goal- oriented actions. However, recording a broader comprehensive set of SPIs helps identify the strengths and weaknesses of a country's road safety system. Providing high quality national and international databases that would include comparable SPIs seems to be difficult since a larger number of countries dispose of a small number of identical indicators available for use. Therefore, there is a need for calculating a road safety performance index with a limited number of indicators (RSPI ln n ) which will provide a comparison of a sufficient quality, of as many countries as possible. The application of the Data Envelopment Analysis (DEA) method and correlative analysis has helped to check if the RSPI ln n is likely to be of sufficient quality. A strong correlation between the RSPI ln n and the RSPI has been identified using the proposed methodology. Based on this, the most contributing indicators and methodologies for gradual monitoring of SPIs, have been defined for each country analyzed. The indicator monitoring phases in the analyzed countries have been defined in the following way: Phase 1- the indicators relating to alcohol, speed and protective systems; Phase 2- the indicators relating to roads and Phase 3- the indicators relating to trauma management. This will help achieve the standardization of indicators including data collection procedures and selection of the key list of indicators that need to be monitored. Based on the results, it has been concluded that the use of the most contributing indicators will make it possible to assess the level of road safety on a territory, with an acceptable quality score by focusing on the low-ranked countries. A smaller set of significant indicators defined in this manner can serve for a fast and simple understanding of a road safety situation and assessment of effects of measures undertaken. Also, this universal index approach is applicable in cases when a broader comprehensive set of indicators is analyzed, which provides a more accurate identification of weaker points and rank the countries in a more meaningful way. Copyright © 2018 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Alila, Y.; Schnorbus, M.
2005-12-01
The debate regarding peak flow responses to forest clearcutting and road building in the maritime regions of the Pacific Northwest has attracted much attention over the past several decades and its outcome is an important scientific and operational concern. Although there appears to be general consensus that small peak discharge events are increased following forest management activities, little conclusive evidence exists regarding the impact of forest management activities on large events. Statistical tests in traditional paired watershed studies have been used to accept or reject hypotheses regarding peak flow responses to clearcutting and roads but provided no insight into watershed processes and other factors leading to their outcome. Furthermore, statistical analyses of peak flow responses to forestry activities in traditional paired watershed studies are confounded by the many factors that may contribute to management effects on watershed hydrology as well as by issues such as shortness of streamflow records and climate variability. To this end, a new perspective is offered in the debate regarding peak flow responses to clearcutting and road building in the maritime regions of the Pacific Northwest by combining numerical modeling with high-quality hydro-meteorological data collected at the 10-km2 Carnation Creek on the west coast of Vancouver Island, British Columbia (BC). In this approach we explicitly account for changes in evapotranspiration loss, forest road construction and, in particular, introduce the concept of the competing influences of matrix versus preferential hillslope runoff. For scenarios involving road construction, forest clearcutting (52% cut rate) and roads and clearcutting combined, peak discharge increases decrease with decreasing event frequency and statistically significant ( = 0.05) increases in peak flow are confined to events with a 1 year or lower return period. For a range of return periods from 0.17 to 20 years, the effect (i.e. increase in peak discharge) of clearcutting alone is more severe than roads alone whereas the combined effect of roads and clearcutting is equal to the addition of the isolated treatments effects. The lower efficiency of the forest canopy in intercepting rainfall for large storms compared to small storms and the increasing proportion of preferential flow in hillslope runoff as event size increases appears to be the main reason for the declining peak flow response to clearcutting. Changes in soil moisture conditions are thought to be relatively unimportant given the significance of preferential hillslope runoff. The weakening response of peak flows to roads with increasing event size is related to higher subsurface flow rates associated with preferential flow coupled with a general lowering of the water table below road cuts; this reduces direct channel interception of hillslope runoff and tends to offset gains in channel flow from direct culvert discharge from the road network.
Gokulakrishnan, P.
2015-01-01
In Indian four-lane express highway, millions of vehicles are travelling every day. Accidents are unfortunate and frequently occurring in these highways causing deaths, increase in death toll, and damage to infrastructure. A mechanism is required to avoid such road accidents at the maximum to reduce the death toll. An Emergency Situation Prediction Mechanism, a novel and proactive approach, is proposed in this paper for achieving the best of Intelligent Transportation System using Vehicular Ad Hoc Network. ESPM intends to predict the possibility of occurrence of an accident in an Indian four-lane express highway. In ESPM, the emergency situation prediction is done by the Road Side Unit based on (i) the Status Report sent by the vehicles in the range of RSU and (ii) the road traffic flow analysis done by the RSU. Once the emergency situation or accident is predicted in advance, an Emergency Warning Message is constructed and disseminated to all vehicles in the area of RSU to alert and prevent the vehicles from accidents. ESPM performs well in emergency situation prediction in advance to the occurrence of an accident. ESPM predicts the emergency situation within 0.20 seconds which is comparatively less than the statistical value. The prediction accuracy of ESPM against vehicle density is found better in different traffic scenarios. PMID:26065014
On-Board Detection of Pedestrian Intentions
Fang, Zhijie; Vázquez, David
2017-01-01
Avoiding vehicle-to-pedestrian crashes is a critical requirement for nowadays advanced driver assistant systems (ADAS) and future self-driving vehicles. Accordingly, detecting pedestrians from raw sensor data has a history of more than 15 years of research, with vision playing a central role. During the last years, deep learning has boosted the accuracy of image-based pedestrian detectors. However, detection is just the first step towards answering the core question, namely is the vehicle going to crash with a pedestrian provided preventive actions are not taken? Therefore, knowing as soon as possible if a detected pedestrian has the intention of crossing the road ahead of the vehicle is essential for performing safe and comfortable maneuvers that prevent a crash. However, compared to pedestrian detection, there is relatively little literature on detecting pedestrian intentions. This paper aims to contribute along this line by presenting a new vision-based approach which analyzes the pose of a pedestrian along several frames to determine if he or she is going to enter the road or not. We present experiments showing 750 ms of anticipation for pedestrians crossing the road, which at a typical urban driving speed of 50 km/h can provide 15 additional meters (compared to a pure pedestrian detector) for vehicle automatic reactions or to warn the driver. Moreover, in contrast with state-of-the-art methods, our approach is monocular, neither requiring stereo nor optical flow information. PMID:28946632
Identifying security checkpoints locations to protect the major U.S. urban areas
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cuellar-Hengartner, Leticia; Watkins, Daniel; Kubicek, Deborah A.
Transit networks are integral to the economy and to society, but at the same time they could allow terrorists to transport weapons of mass destruction into any city. Road networks are especially vulnerable, because they lack natural checkpoints unlike air networks that have security measures in place at all major airports. One approach to mitigate this risk is ensuring that every road route passes through at least one security checkpoint. Using the Ford-Fulkerson maximum-flow algorithm, we generate a minimum set of checkpoint locations within a ring-shaped buffer area surrounding the 50 largest US urban areas. We study how the numbermore » of checkpoints changes as we increase the buffer width to perform a cost-benefit analysis and to identify groups of cities that behave similarly. The set of required checkpoints is surprisingly small (10-124) despite the hundreds of thousands of road arcs in those areas, making it feasible to protect all major cities.« less