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Geographically, Chitradurga district, in central Karnataka, is well connected by roads-National Highways State highways, and hence density of vehicles traversing is also high. Having said this, morbidity and mortality by RTAs is also on a high, however this is preventable. Thus this study was done know the incidence and also implement safety measures and to strengthen legal measures. Injuries caused by RTAs to chest and abdomen were studied in detail. This study includes victims died of RTA of age of all year age groups. Most incidents occurred in National Highways, Urban roads and village roads. Majority of the cases died on spot by fatal injuries. Heavy motor and two wheeler vehicles were involved in majority of cases followed by two wheelers only. External injuries most frequently observed were abrasions. Fatal injuries were noted in the region of head followed by abdomen and chest. [ABSTRACT FROM AUTHOR]

The passengers inside vehicles could be exposed to high levels of air pollutants particularly while driving on highly polluted and congested traffic roadways. In order to study such exposure levels and its relation to the cabin ventilation condition, a monitoring campaign was conducted to measure the levels inside the three most common types of vehicles in Tehran, Iran (a highly air polluted megacity). In this regard, carbon monoxide (CO) and particulate matter (PM) were measured for various ventilation settings, window positions, and vehicle speeds while driving on the Resalat Highway and through the Resalat Tunnel. Results showed on average in-cabin exposure to particle number and PM10 for the open windows condition was seven times greater when compared to closed windows and air conditioning on. When the vehicle was passing through the tunnel, in-cabin CO and particle number increased 100 and 30%, respectively, compared to driving on highway. Air exchange rate (AER) is a significant factor when evaluating in-cabin air pollutants level. AER was measured and simulated by a model developed through a Monte Carlo analysis of uncertainty and considering two main affecting variables, vehicle speed and fan speed. The lowest AER was 7 h−1 for the closed window and AC on conditions, whereas the highest AER was measured 70 h−1 for an open window condition and speed of 90 km h−1. The results of our study can assist policy makers in controlling in-cabin pollutant exposure and in planning effective strategies for the protection of public health. [ABSTRACT FROM AUTHOR]

In order to improve the estimation accuracy of highway traffic parameters, on the basis of the macro traffic flow model and the state-space model, this paper proposes a traffic parameter estimation method based on hybrid particle filter according to the Bayesian theory. Considering the sensitivity of the estimation results to the changes of the model parameters, and to avoid the impacts from the preset fixed model parameters on the estimation accuracy, this paper establishes the relationship between the free flow velocity and the traffic condition (saturation V/C) and proposes an adaptive adjustment strategy for model parameters under the effect of traffic conditions. The test results show that: the traffic parameter estimation based on hybrid particle filter is much more accurate than the Kaiman filtering estimation and can quickly identify the obvious fluctuations in traffic volume, exhibiting its strong stability in the rainy weather. In addition, the adaptive adjustment strategy for model parameters under the influence of traffic conditions can significantly improve the accuracy of the traffic parameter estimation, and can still provide fairly good estimation results even in the event of an accident. [ABSTRACT FROM AUTHOR]

Secondary crashes (SCs) or crashes that occur within the boundaries of the impact area of prior, primary crashes are one of the incident types that frequently affect highway traffic operations and safety. Existing studies have made great efforts to explore the underlying mechanisms of SCs and relevant methodologies have been evolving over the last two decades concerning the identification, modeling, and prevention of these crashes. So far there is a lack of a detailed examination on the progress, lessons, and potential opportunities regarding existing achievements in SC-related studies. This paper provides a comprehensive investigation of the state-of-the-art approaches; examines their strengths and weaknesses; and provides guidance in exploiting new directions in SC-related research. It aims to support researchers and practitioners in understanding well-established approaches so as to further explore the frontiers. Published studies focused on SCs since 1997 have been identified, reviewed, and summarized. Key issues concentrated on the following aspects are discussed: (i) static/dynamic approaches to identify SCs; (ii) parametric/non-parametric models to analyze SC risk, and (iii) deployable countermeasures to prevent SCs. Based on the examined issues, needs, and challenges, this paper further provides insights into potential opportunities such as: (a) fusing data from multiple sources for SC identification, (b) using advanced learning algorithms for real-time SC analysis, and (c) deploying connected vehicles for SC prevention in future research. This paper contributes to the research community by providing a one-stop reference for research on secondary crashes. [ABSTRACT FROM AUTHOR]

The primary purpose of the speed limit system is to enforce reasonable and safe speed. To reduce secondary problems such as accidents and queuing, Variable Speed Limits (VSL) has been suggested. In this paper VSL is used to better safety and traffic parameters. Traffic parameters including speed, queue length and stopping time have been pondering. For VLS, an optimization decision tree algorithm with the function of microscopic simulation was used. The results in case of sub saturated, saturated and supersaturated at a bottleneck are examined and compared with the Allaby logic tree. The results show that the proposed decision tree shows an improved performance in terms of safety and comfort along the highway. The VSL pilot project is part of the Road Safety Improvement Program included in Iran's road safety action plan that is in the research process in the BHRC Research Institute, Road and Housing & Urban Development Research that is planned for next 10-year Transportation safety view Plan. [ABSTRACT FROM AUTHOR]

Newly-constructed and reconstructed highway pavements under the effect of traffic loading and climatic severity deteriorate progressively and need preservation intervention after a certain number of years following their construction. In the literature, the term ‘rest period’ has been used to refer to the number of years that elapse between the construction completion to the application of first major repair activity. The rest period is a critical piece of information that agencies use to not only plan and budget for the first major repair activity but also to develop more confidently, their life-cycle activity schedules for life cycle costing, work programming, and long-term plans. However, the literature lacks established procedures for predicting rest periods on the basis of pavement performance thresholds. In the absence of such resources, highway agencies rely mostly on expert opinion for establishing the rest periods for their pavement sections. In addressing this issue, this paper presents a statistical methodology for establishing the rest periods for newly-constructed or reconstructed pavements. The methodology was demonstrated using empirical data from in-service pavements in a Midwestern State in the US. The paper’s results show that the rest periods of newlyconstructed and reconstructed highway pavements are significantly influenced by their functional class, surface material type, traffic loading level, and climate severity. [ABSTRACT FROM AUTHOR]

This paper is devoted to the problem of reducing vehicle energy consumption. The authors consider the optimisation of highway driving cycle a way to use the kinetic energy of a car more effectively at various road conditions. The model of a vehicle driving control at the highway which consists of elementary cycles, such as accelerating, free rolling and deceleration under forces of external resistance, was designed. Braking, as an energy dissipation regime, was not included. The influence of the various longitudinal profiles of the road was taken into consideration and included in the model. Ways to use the results of monitoring road and traffic conditions are presented. The method of non-linear programming is used to design the optimal vehicle control function and phase trajectory. The results are presented by improved typical driving cycles that present energy saving as a subject of choice at a specified schedule. [ABSTRACT FROM AUTHOR]

Three different type of double road trains are selected as simulation model, which is commonly used in developed countries and regions in order to improve the efficiency of road transport and the development of China's logistics industry. The passing ability simulation model of double road train is established based on Auto Turn, and China's current longest tractor-semitrailer is used as a comparison. Simulation models of highway ramp, first class highway and second class highway are established according to the requirement of JTG D20-2006 ‘Design Specification for Highway Alignment’. Adaptability of double road train and highway structure parameter is researched by analyzing different types of double road train turn left, turn right and turn around on the road. The type of double road train which can meet China's standards is recommended. The result can promote the application of double road train and give some advice for improving passing ability. [ABSTRACT FROM AUTHOR]

Unsuitable driving behaviors often lead to the occurrence of traffic accidents. To reduce accidents and to prolong human life, simulated investigations are highly desirable to evaluate the effect of traffic safety in terms of number of traffic accidents. In this paper, a three-lane traffic flow model is proposed to analyze the probability of the occurrence of traffic accidents on highway. We define appropriate driving rules for the forward moving and lane changing of the vehicles. Three types of vehicle accidents are designed to investigate the relationships between different driving behaviors and traffic accidents. We simulate four road driving strategies, and compute the traffic flow, velocity, lane-changing frequency and the probability of the occurrence of traffic accidents for different road driving strategies. According to the simulation and analysis, it is shown that the probability of the occurrence of traffic accidents can be reduced by using the specified road driving strategies. Additionally, we found that the occurrence of traffic accidents can be avoided when the slow vehicles are suitably constrained to move on a three-lane highway. [ABSTRACT FROM AUTHOR]

Portable changeable message signs (PCMSs) have been employed in highway work zones as a temporary traffic control device for decades in the United States. Results of previous research showed that the traditional text-based PCMS had several limitations, such as having a short range of legibility and being difficult to read by elderly and non-English-speaking drivers. A few simulation studies indicated that using graphic-aided PCMSs could likely overcome these limitations. This paper presents the results of field experiments that were conducted to determine the effectiveness of graphic-aided PCMS in reducing vehicle speeds in the upstream of highway work zones. In field experiment Phase I, a full-matrix PCMS was programmed to display a work zone graphic and a flagger graphic, which were similar to the W21-1 sign and W20-7 sign, respectively, specified by the Manual on Uniform Traffic Control Devices. In field experiment Phase II, the PCMS was programmed to display two alternative work zone graphics along with the original work zone graphic. 1115 and 1600 valid vehicle speed data were collected during field experiments Phase I and Phase II, respectively. The results of data analysis suggested that graphic-aided PCMSs reduced mean vehicle speeds between 13% and 17% in the upstream of a work zone. This study provided valuable knowledge to government agencies and the transportation industry on how to regulate and implement graphic-aided PCMS in highway work zones. [ABSTRACT FROM AUTHOR]

Increasing worldwide motor vehicle traffic leads to the question of the possible environmental consequences. This paper aims to analyse metal leaching in a highway embankment using both field and laboratory experiments. Soil, soil solution and road runoff were collected along one of the oldest highways in the world to characterize leaching of the metals Cd, Cr, Cu, Ni, Pb and Zn. Batch, column and adsorption experiments were carried out to study the reliability and transferability of laboratory approaches. Depending on the element, the ratio of particle-bound metals in road runoff varied between 15-90%. Metal levels in embankment soils were significantly higher compared to a reference site in a forest at 800 m distance (up a factor of 30). High metal concentrations in soil solution at 50 cm soil depth were not a direct result of road runoff but rather of elevated concentrations in the soil matrix. The use of batch S4 elution was found to be the best overall laboratory method to predict soil solution concentrations in field. Adsorption experiments showed a relative increase in retention capacity in roadside soil of up to a factor of 20 after nearly 100 years of operation. The input of alkaline dust and organic carbon into roadside soils increases its retention capacity in the long term. [ABSTRACT FROM AUTHOR]

Speed limit has significant effect on the emission reductions of urban and highway traffic. This paper studied the relationship between speed limit and vehicle exhaust emissions with the aim of finding the optimal speed limit which would result in the reduction of emissions in the study area. A test section of S342 in Wuxi, China was selected for this study. An integrated model was deployed which combined the microscopic traffic simulation model VISSIM with the emission model established by the data collected from on-board portable emission measurement system OBEAS-3000. VISSIM recorded the second-by-second speed and acceleration of individual vehicle under different speed limit scenarios as the input data. The emission model outputs vehicle emissions through relating emissions to the instantaneous speed and acceleration of the vehicle. Speed limit scenarios were set from 90 to 40 km/h at a decrement of 5km/h and heavy vehicles weighted above 2t in total occupied near 20%. Distance-based emission rate (g/km) was used as the performance measure. The simulation results showed that, vehicles released least CO emissions with a speed limit of 70km/h, and 80km/h was optimal for HC and NOx emissions. [ABSTRACT FROM AUTHOR]

Many studies have documented the merits and problems of nighttime work for highway construction. Most of these studies have examined the safety of the construction site for workers or the traveling public. Illumination standards, sign requirements, and crash rate data have been studied to determine whether crash rates increase during nighttime hours, and the reasons for these crashes. Few studies have addressed either the effects on cost or productivity that nighttime construction has on a project. This study used hard bid unit prices to focus on the effect that performing certain construction activities at night has on cost and productivity. Specifically, the study assumes that a contractor's bid amount reflects expected relative project productivity and answers the question, 'What impact, if any, does night work have on construction productivity and therefore bid price?' This is the first paper to answer both questions as related. Among the results was the fact that for the most part, the owner would have saved millions of dollars by allowing the contractor the option of working at night or during the day, though some items were bid lowest if the contract allowed for night work only. [ABSTRACT FROM AUTHOR]

Abstract: This paper reviews road safety performance in the United States. The paper develops a framework for assessing dimensions of road safety, and analyzes the importance of economic factors, travel patterns, demographics, road/traffic/vehicle technology, driver behavior, and public policy. Issues and challenges for future road safety research are discussed. [Copyright &y& Elsevier]

This work presents a fuzzy logic-based highway on-ramp control (HORC) approach that works by controlling the traffic lights at the on-ramp to facilitate the flow of traffic onto the highway. The proposed HORC comprises a fuzzy logic system and a decision-making model. The former determines the switching probability of the traffic light, while the latter makes the decision concerning the switching of the traffic light. The HORC requires only the velocities and the difference of velocities of the vehicles that are entering the highway. Simulation results indicate that the proposed HORC outperforms pre-timed ramp control. [ABSTRACT FROM PUBLISHER]

This research was conducted to determine how best to incorporate portable rumble strips into traffic control plans for short-term work zones. One objective of the research was to provide guidance on how existing traffic control plans could be amended to include provisions for the evaluated devices. This research focused on rumble strips that were considered beneficial for any type of work zone where the duration is one day or less. The tests on the portable rumble strips were conducted on a closed roadway surrounding the Kansas Speedway in Kansas City, Kansas, and in a closed park-and-ride parking facility in Lawrence, Kansas. The rumble strips tested in this study were two different types of reusable temporary rumble strips made out of steel with a rubber bottom and four generations of plastic rumble strips. From this study the best solution for most short-term work zones would be the latest generation of plastic rumble strips tested. The earlier generations did not perform as well as the fourth generation especially at 60 mph (96.6 km/hr). The steel rumble strips also hold some promise; however, the structural integrity of the steel rumble strips is an issue that needs to be addressed. [ABSTRACT FROM AUTHOR]

Abstract: Flexible-term highway concessions are becoming quite popular around the world as a means of mitigating the traffic risk ultimately allocated to the concessionaire. The most sophisticated mechanism within flexible-term concession approaches is the least present value of the revenues (LPVR). This mechanism consists of awarding the concession to the bidder who offers the least present value of the revenues discounted at a discount rate fixed by the government in the contract. Consequently, the concession will come to an end when the present value of the revenues initially requested has been eventually reached. The aim of this paper is to evaluate the effect that the discount rate established by the government in the bidding terms has on the traffic-risk profile ultimately allocated to the concessionaire. To analyze this effect, a mathematical model is developed in order to obtain the results. I found that the lower the discount rate the larger will be the traffic risk allocated to the concessionaire. Moreover, I found that, if a maximum term is established in the contract, the lower the discount rate, the less skewed towards the downside will be the traffic-risk profile allocated to the concessionaire. [ABSTRACT FROM AUTHOR]

Abstract: We propose a modification of the widely known Benjamin–Johnson–Hui (BJH) cellular automaton model for single-lane traffic simulation. In particular, our model includes a ‘slow-to-stop’ rule that exhibits more realistic microscopic driver behaviour than the BJH model. We present some statistics related to fuel economy and pollution generation and show that our model differs greatly in these measures. We give concise results based on extensive simulations using our system. [ABSTRACT FROM AUTHOR]

Most important mode of transportation is highway in Turkey. After the construction of highways, pavement distresses occur via traffic, climate and environment etc. Except of maintenance activities, rehabilitation activities must be done. Because rehabilitation activities required more cost, it is impossible to interface to all regions to be necessary rehabilitation. It is generally taken into consideration only traffic volume and rehabilitation cost for choosing of rehabilitation regions. But priority determining is one of the important factors for highway user benefits Highway user benefits can be defined as reduction in highway user cost. The aim of this paper is investigation of effect to highway user time lost costs because of pavement serviceability loss in Turkish roads. For this aim, highway user time lost costs was investigated with public survey made in pilot cities. These cities were determined according to various traffic volumes, various income levels, and different vehicle dispersions. Selected cities are Isparta, Adapazari, and Samsun. As a result, traffic user time costs was determined as automobile user costs are similar but bus and truck user costs are low as Greece costs. [ABSTRACT FROM AUTHOR]

We investigate connectivity in the ad hoc network formed between vehicles that move on a typical highway. We use a common model in vehicular traffic theory in which a fixed point on the highway sees cars passing it that are separated by times with an exponentially distributed duration. We obtain the distribution of the distances between the cars, which allows us to use techniques from queuing theory to study connectivity. We obtain the Laplace transform of the probability distribution of the connectivity distance, explicit expressions for the expected connectivity distance, and the probability distribution and expectation of the number of cars in a platoon. Then, we conduct extensive simulation studies to evaluate the obtained result. The analytical model that we present is able to describe the effects of various system parameters, including road traffic parameters (i.e., speed distribution and traffic flow) and the transmission range of vehicles, on the connectivity. To more precisely study the effect of speed on connectivity, we provide bounds obtained using stochastic ordering techniques. Our approach is based on the work of Miorandi and Altman, which transformed the problem of connectivity distance distribution into that of the distribution of the busy period of an equivalent infinite server queue. We use our analytical results, along with common road traffic statistical data, to understand connectivity in vehicular ad hoc networks. [ABSTRACT FROM AUTHOR]

Abstract: Highway work zones interrupt regular traffic flows and create safety problems. Improving safety without sacrificing the main function of highways is a challenging task that traffic engineers and researchers have to confront. In this study, the concept of using crash severity index (CSI) for work zone safety evaluation was proposed and a set of CSI models were developed through the modeling of work zone crash severity outcomes. A CSI is a numerical value between zero and one that is estimated from given work zone variables. It is interpreted as the likelihood of having fatality/fatalities when a severe crash occurs in a given work zone. The CSI models were developed using a three-step approach. First, a wide range of crash variables were examined in a comprehensive manner and the significant risk factors that had impact on crash severity were selected. Second, the CSI models were developed using logistic regression technique by incorporating the selected risk factors. Finally, the developed models were validated using the recent crash data and their ability in assessing work zone risk levels were analyzed. Results of this study showed that CSI models can provide straightforward measurements of work zone risk levels. [Copyright &y& Elsevier]

Previous studies suggest that eastern chipmunks (Tamias striatus) avoid roads, but it is unclear whether vehicle traffic plays a role in this avoidance. The purpose of this study was to determine whether road avoidance in chipmunks increases with traffic. We tracked the movements of 68 chipmunks released near roads with widely varying volumes of traffic. Our results suggest that chipmunks responded to changes in traffic volume only in the preliminary stages of their movement pathways. Apart from this initial response, we found that road avoidance was independent of traffic, with evidence that chipmunks avoided both the roadside verge and the road surface. Because avoidance of roads was independent of traffic, effects of roads on populations of chipmunks may be manifest more as population subdivision than as direct mortality. [ABSTRACT FROM AUTHOR]

Abstract: The effects of an increase in Heavy Goods Vehicles (HGVs) on merging behaviour and on mental workload of motorists during filtering in and out of traffic were studied. Participants drove in a driving simulator in a total of 12 conditions; twice in each of two weather conditions and in three traffic conditions. The weather conditions were clear weather and foggy weather. The traffic conditions were without HGVs (i.e. only private cars), the current mix of HGVs and private cars, and a condition with a 70% increase of HGVs leading to an HGV column in the slow lane. The focus of the study was on assessing effects on behaviour and mental workload during filtering into traffic, and during exiting from the motorway. During the experiment driving performance was registered, behaviour was observed, self reports were collected, and the participant''s heart rate was recorded. The results showed that directly after filtering into traffic the variation in driving speed increased and the minimum time headway decreased with an increase in the proportion of HGVs. Joining motorway traffic was considered to involve greater effort and risk in the condition with a column of HGVs. The effects of the conditions on heart rate are less clear, although the moment when the participants joined the traffic is clearly visible. The effects of weather conditions were limited, drivers adapting their driving behaviour in adverse weather by reducing speed. To exit the motorway is not a difficult manoeuvre. For that reason the lane change from the left hand to the right hand lane that preceded the exit was analysed. Although increased mental effort was reported and the lane change was visible in the heart rate record, no critical changes as a result of increase in proportion of HGVs were found for this manoeuvre. However, in the condition with a column of HGVs, the exit that had to be taken was most frequently missed as HGVs obstructed the view of the exit signs. It is concluded that an increase in HGVs will make merging into traffic more mentally demanding and will decrease safety margins. [Copyright &y& Elsevier]

Faced with immense increases in automobile traffic, during the 1920s, Los Angeles city engineers improved Whittier Boulevard through the east side. To keep costs low, the engineers took land from parks and playgrounds. In short, local residents, mostly lower-income Mexican Americans, Jews, and other ‘undesirables,’ would pay the social costs of highway building in East Los Angeles. By the 1940s, poorly designed roads helped rule the reformist politics of Edward Roybal but also helped state transportation planners to justify extensive freeway construction in the area. Spatial exploitation for highways contributed to the projection of place-based ethnic identity among the Mexican American people who became a majority of east side population after World War II. [ABSTRACT FROM AUTHOR]