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Copyright of Revista Fatec Zona Sul (REFAS) is the property of Revista Fatec Zona Sul (REFAS) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The growth of smart cities is fueled by the vast rise in wireless smart gadgets and uninterrupted connectivity. WiFi is the dominant wireless technology, enabling Internet-of-Things (IoT) connectivity in smart cities due to its ubiquitous access points and low deployment cost. However, smart city applications offer a wide range of services with different quality-of-service (QoS) demands. This paper addresses packet delivery latency as one of the QoS metrics affecting many time-sensitive smart city services. Thus, the paper proposes employing software-defined networking (SDN) to control the traffic load of WiFi access points (APs), preserving its symmetry in a city-wide coverage of WiFi-connected IoT gateways or fog nodes. These gateways receive data packets from smart city/IoT devices via wireless links and forward them over a city-deployed WiFi network to their management entities or servers. Three SDN-based algorithms are devised to reduce the gateways' packet-forwarding delay and keep a symmetric traffic load at the WiFi network APs. The algorithms are developed and tested using a real hardware setup constituting WiFi devices without additional requirements on the IoT gateways (WiFi clients) or the APs, such as support for a specific roaming protocol or bandwidth-consuming signaling such as sending probe packets. Extensive hardware experimentation shows that the SDN controller, via the proposed algorithms, can effectively reduce the packet forwarding latency of IoT gateways by carefully selecting the IoT gateway with the highest packet latency and seamlessly handing it over to the least-loaded covering AP. [ABSTRACT FROM AUTHOR]

The significant advancements in intelligent transportation systems (ITS) have contributed to the increased development in traffic modeling. These advancements include prediction and simulation models that are used to simulate and predict traffic behaviors on highway roads and urban networks. These models are capable of precise modeling of the current traffic status and accurate predictions of the future status based on varying traffic conditions. However, selecting the appropriate traffic model for a specific environmental setting is challenging and expensive due to the different requirements that need to be considered, such as accuracy, performance, and efficiency. In this research, we present a comprehensive literature review of the research related to traffic prediction and simulation models. We start by highlighting the challenges in the long-term and short-term prediction of traffic modeling. Then, we review the most common nonparametric prediction models. Lastly, we look into the existing literature on traffic simulation tools and traffic simulation algorithms. We summarize the available traffic models, define the required parameters, and discuss the limitations of each model. We hope that this survey serves as a useful resource for traffic management engineers, researchers, and practitioners in this domain. [ABSTRACT FROM AUTHOR]

Over the last few years, energy optimization in wireless sensor networks (WSNs) has drawn the attention of both the research community and actual users. Sensor nodes are powered by attached batteries that are considered as a critical aspect of sensor nodes design. Besides, the constraint of the limited battery capacity is associated with the concern on how to reduce the energy consumption of nodes to extend the network lifetime. In this context, the purpose of this study is to implement an adaptive medium access control (MAC) for energy saving and traffic control enhancement. This program was designed to arrange nodes into two priority groups according to their traffic rate and data transmission packet delay. This fuzzy algorithm depends on their queue length where it is implemented into the carrier sense multiple access with collision avoidance (CSMA/CA) algorithm. However, other types of nodes should send their data during the contention-free period with a GTS reallocation scheme. Those nodes are classified as low priority access to the medium, and their data transmission is scheduled using time division multiple access methods. Moreover, this proposed scheme dynamically adjusts the contention access period length to ensure that nodes can complete their data transmission during the same super-frame. Simulation results are done using the network simulator tool (NS-2), and it has improved efficiency regarding the IEEE-802.15.4 standard. [ABSTRACT FROM AUTHOR]

The article is focused on dynamic driving in road transport. Current systems on the market are referred to as dynamic but have their limitations. Traffic management is an important aspect to ensure the proper functioning and safety of transport as an element of critical infrastructure. Ensuring the prevention of possible threats can minimize the possibility of threatening other elements of critical infrastructure. The proposed method deals with dynamic driving in road transport. Dynamically controlled traffic lights should ensure greater smoothness, safety and reduce the number of harmful substances emitting vehicles. [ABSTRACT FROM AUTHOR]

Abstract There is evidence that local traffic density and living near major roads can adversely affect health outcomes. We aimed to assess the relationship between local road length, proximity to primary highways, and cause-specific mortality in the 1991 Canadian Census Health and Environment Cohort (CanCHEC). In this long-term study of 2.6 million people, based on completion of the long-form census in 1991 and followed until 2011, we used annual residential addresses to determine the total length of local roads within 200 m of postal code representative points and the postal code's distance to primary highways. The association between exposure to traffic and cause-specific non-accidental mortality was estimated using Cox proportional hazards models, adjusting for individual covariates and contextual factors, including census division-level proportion in high school, the percentage of recent immigrants, and neighborhood income. We performed sensitivity analyses, including adjustment for exposure to PM 2.5 , NO 2 , or O 3 , restricting to subjects in core urban areas, and spatial variation by climatic zone. The hazard ratio (HR) for all non-accidental mortality associated with an interquartile increase in length of local roads was 1.05 (95% CI 1.04, 1.05), while for an interquartile range increase in proximity to primary highways, the HR was 1.03 (95% CI 1.02, 1.04). HRs by traffic quartile increased with increasing lengths of local roads, as well as with closer proximity to primary highways, for all mortality causes. The associations were stronger within subjects' resident in urban core areas, attenuated by adjustment for PM 2.5 , and HRs showed limited spatial variation by climatic zone. In the CanCHEC cohort, exposure to higher road density and proximity to major traffic roads was associated with increased mortality risk from cerebrovascular and cardiovascular disease, ischemic heart disease, COPD, respiratory disease, and lung cancer, with unclear results for diabetes. Highlights • The association between exposure to traffic and mortality was estimated using Cox proportional hazards models. • Hazard ratios (HRs) for mortality related to length of local roads and proximity to primary highways were calculated. • HRs by traffic quartile increased with greater lengths of local roads, and with closer proximity to main highways. • The associations were stronger within subjects' resident in urban core areas, attenuated by adjustment for PM 2.5. • HRs showed limited spatial variation by climatic zone. [ABSTRACT FROM AUTHOR]

BACKGROUND: There is no consensus among medical experts as to whether patients with epilepsy (PWEs) should be permitted to drive. PWEs who have had uncontrolled seizures in the past year are at an increased risk of road traffic accidents, often leading to the destruction of property, injury, or death. Currently, there is no clear policy on whether PWEs can drive in Saudi Arabia. Existing policies attempt to balance the potentially harmful and beneficial aspects of the issue. The purpose of this study was to measure the prevalence of PWEs who are unfit to drive. MATERIALS AND METHODS: Data were collected by interviews, a structured validated questionnaire, and a review of the medical records of 140 PWEs, with a response rate of 84%. RESULTS: Fifty four percent of PWEs were found unfit to drive. Of the 118 participants, 17.7% did not drive and 97 (82.3%) drove. Of the 21 patients who did not drive, 14 (11.8% of the total sample) never drove and 7 (5.9% of the total sample) stopped driving because of epilepsy. Of the 104 patients who drove, 45 (43.2% of the total sample) had a history of seizures while they drove. These incidents had resulted in the involvement of 28 patients (26.9% of the total sample) in motor vehicle accidents and 17 (16.3% of the total sample) patients being admitted to the emergency room. CONCLUSION: Structured regulation and licensing procedures are necessary for PWEs to drive safely. Regulations in other countries demand that seizures be controlled for 1 year before epileptic patients are allowed unrestricted driving. Such regulations would improve road safety in Saudi Arabia. [ABSTRACT FROM AUTHOR]

Percolation transition is widely observed in networks ranging from biology to engineering. While much attention has been paid to network topologies, studies rarely focus on critical percolation phenomena driven by network dynamics. Using extensive real data, we study the critical percolation properties in city traffic dynamics. Our results suggest that two modes of different critical percolation behaviors are switching in the same network topology under different traffic dynamics. One mode of city traffic (during nonrush hours or days off) has similar critical percolation characteristics as small world networks, while the other mode (during rush hours on working days) tends to behave as a 2D lattice. This switching behavior can be understood by the fact that the high-speed urban roads during nonrush hours or days off (that are congested during rush hours) represent effective long-range connections, like in small world networks. Our results might be useful for understanding and improving traffic resilience. [ABSTRACT FROM AUTHOR]

Background The prevalence of diabetes is on rise worldwide and environmental factors are being increasingly recognized to be involved in this rise. An emerging body of evidence has evaluated the impact of long-term exposure to noise on diabetes mellitus, highlighting the need to synthesize this evidence. Objectives To systematically review and conduct meta-analysis of the available evidence on the association between long-term exposure to transport and occupational noise exposure and diabetes mellitus. Methods Selected databases were searched for available evidence published till September 13th, 2017 following MOOSE guidelines. The quality of articles was assessed using the Newcastle–Ottawa Scale. Random effects meta-analysis was applied to abstract combined estimates for diabetes mellitus per 5 dB increase in noise exposure. We evaluated the heterogeneity applying Cochran's Q test and quantified it using I 2 statistic. Meta-regressions were conducted to identify sources of heterogeneity. Publication bias was evaluated using funnel plot and Egger's test. Results Fifteen studies met our inclusion criteria of which nine including five prospective cohorts, two cross-sectional and two case-control studies with a total number of 444460 adult participants and 17430 diabetes mellitus cases included in meta-analyses. We observed a 6% (95% confidence interval (CI): 3%, 9%) increase in the risk of diabetes mellitus per 5 dB increase in noise exposure regardless of its source. Source-specific analyses were suggestive for stronger associations for air traffic noise (combined odds ratio: 1.17; 95% CI: 1.06, 1.29 per 5 dB increase in exposure) flowed by road traffic noise (combined odds ratio: 1.07; 95% CI: 1.02, 1.12). We observed some indications of publication bias; however the findings were robust after trim and fill test. Meta-regression analyses showed that the adjustment in general, and not specifically related to air pollution, could predict the between-study heterogeneity in reported associations. Conclusions The results indicate an increased risk of diabetes mellitus associated with noise exposure, mainly related to air and road traffic. [ABSTRACT FROM AUTHOR]

This work deals with the need and possibility of building car parks in Bucharest above Dâmboviţa river. They included analyses referring to the evolution of the number of existing vehicles in Bucharest, an analysis of the number of vehicles in Bucharest, as compared to other European capitals, and also certain elements leading to the possibility and profitability of building a car park above Dâmboviţa River. [ABSTRACT FROM AUTHOR]

Experimental and numerical studies are performed to analyze a concrete bridge under moving vehicular loads considering the effects of the damage cracks, stochastic traffic flows, and bridge surface roughness. Specifically, (1) the crack zone in the concrete bridge is modeled by a damage function with three parameters, i.e. the length of damaged zone, the magnitude of the damage, and the variation of Young's modulus of the material; (2) a cellular automation (CA) based traffic flow model is adopted, which can capture the basic features of the probabilistic traffic flows using realistic traffic rules; (3) a three-dimensional (3D) vehicle model and a single vehicle model are each used to simulate the vehicles in the traffic flow for computational efficiency; and (4) the bridge and vehicle coupled equations are established by combining those for the bridge and vehicles using the displacement and interaction force relationship at the contact patches. The experimental and numerical investigations are conducted to validate the proposed modeling methodology. As an illustration, a prototype concrete bridge structure with partial damage is studied. Finally, parametric studies are conducted to study the effects of damage cracks, stochastic traffic flows, and surface roughness on the dynamic displacement, impact factor, impact force, and dynamic load coefficient of the bridge. [ABSTRACT FROM AUTHOR]

Abstract: Large scale road traffic is a complex system that could be modelled with a multilevel approach. Most of the multilevel models from the literature have fixed a priori the two levels of detail (micro-meso, micro-macro, meso-macro). This paper has two goals: it presents the state of the art related to large scale traffic models, and it gives the main research direction to create a novel multilevel model that support dynamic selection of the level during the simulation. Our proposal is based on an organizational modelling approach and the use of the concept of holon (agent composed of agents). [ABSTRACT FROM AUTHOR]

Increasing the intensity of transport traffic, changing in restructuring and high-speed modes of transport flows more stringent requirements for controls and traffic management impose to ensure the necessary level of efficiency and safety of the transport traffic. To resolve this problem, it is necessary to build road network optimal in length, density and on transport performance indicators. Aim: The aim of the study is to evaluate the workload and analysis of capacity of the road network of modern regional center. Materials and Methods: All studies and calculations in paper, the authors conducted on the example of the road network of the Primorsky district of Odessa (Ukraine). Few streets that are transit arteries of the historic center were chosen to assess the road network capacity. On these streets the movement to the main passenger and transport creating unit - Railway Station is happening. To assess the capacity of the considered road network the methods of field observations were used, because they are based on direct measurements of traffic characteristics in different parts of the road network. Results: The study gave an objective picture of important correspondences. An assessment of degree of loading the considered road network was made; for that the capacity of multilane roadway was calculated. Analysis of the data showed that the state of traffic in the study area is densely saturated. It was made the recommendation for improvement of traffic of modern regional center. [ABSTRACT FROM AUTHOR]

This article describes the methods of mathematical modeling and simulation of processes of local interaction in transport systems. Described transport flow models, developed by the author, based on extension of the microscopic Treiber's model and on the queuing theory. These models cover more details of behavior of flow participants on signal-controlled crossroads. modification. The article describes a model of traffic on the ring road. [ABSTRACT FROM AUTHOR]

Case study on adaptive traffic lights solution implementation at the intersection of Routh Bihar with Street Starlings. Description of the chosen solution for traffic lights at the current intersection between Routh Bihar with Street Starlings. [ABSTRACT FROM AUTHOR]

Hydraulic fracturing (fracking) has been used extensively in the US and Canada since the 1950s and offers the potential for significant new sources of oil and gas supply. Numerous other countries around the world (including the UK, Germany, China, South Africa, Australia and Argentina) are now giving serious consideration to sanctioning the technique to provide additional security over the future supply of domestic energy. However, relatively high population densities in many countries and the potential negative environmental impacts that may be associated with fracking operations has stimulated controversy and significant public debate regarding if and where fracking should be permitted. Road traffic generated by fracking operations is one possible source of environmental impact whose significance has, until now, been largely neglected in the available literature. This paper therefore presents a scoping-level environmental assessment for individual and groups of fracking sites using a newly-created Traffic Impacts Model (TIM). The model produces estimates of the traffic-related impacts of fracking on greenhouse gas emissions, local air quality emissions, noise and road pavement wear, using a range of hypothetical fracking scenarios to quantify changes in impacts against baseline levels. Results suggest that the local impacts of a single well pad may be short duration but large magnitude. That is, whilst single digit percentile increases in emissions of CO 2 , NO x and PM are estimated for the period from start of construction to pad completion (potentially several months or years), excess emissions of NO x on individual days of peak activity can reach 30% over baseline. Likewise, excess noise emissions appear negligible (< 1 dBA) when normalised over the completion period, but may be considerable (+ 3.4 dBA) in particular hours, especially in night-time periods. Larger, regional scale modelling of pad development scenarios over a multi-decade time horizon give modest CO 2 emissions that vary between 2.5 and 160.4 kT, dependent on the number of wells, and individual well fracking water and flowback waste requirements. The TIM model is designed to be adaptable to any geographic area where the required input data are available (such as fleet characteristics, road type and quality), and we suggest could be deployed as a tool to help reach more informed decisions regarding where and how fracking might take place taking into account the likely scale of traffic-related environmental impacts. [ABSTRACT FROM AUTHOR]

Microblogs like Twitter 1 are sources for a lot of useful information. But these information are unstructured. To automatically process it, these information have to be extracted with the help of natural language processing techniques. Corresponding systems for information extraction have to be trained and validated with manual annotated data. This paper presents an approach for the cooperative creation of annotated corpora for training and validation of information extraction systems supported by statistical analyses. 1 https://twitter.com/ [ABSTRACT FROM AUTHOR]

This paper studies the synergic relationship between traffic and tourism in Croatia’s Dubrovnik-Neretva County by the 2020., based on the idicators detected in 2014. It elects the variables that characterise the synergy of traffic and tourism i, speaking from the standpoint of traffic and geography, in the most problematic county in the Republic of Croatia. The basic hypothesis has been confirmed through scientifically obtained research results, through the quantification of the model's variables and the direct growth rates of the designed model. On the basis of scientific insights into the sustainable development of traffic and tourism in Dubrovnik-Neretva County, it is possible to propose a new information model for traffic at the service of the sustainable development of tourism in the County for period 2014.-2020. [ABSTRACT FROM AUTHOR]

Objectives Road traffic injuries ( RTI) have become a leading cause for admissions at Luang Namtha Provincial Hospital (LNPH) in rapidly developing northern Laos. Objectives were to investigate trends, risk factors and better estimates of RTI. Methods Repeated annual surveys were conducted with structured questionnaires among all RTI patients at LNPH from 2007 to 2011. Hospital and police data were combined by capture-recapture method. Results The majority of 1074 patients were young [median 22 years (1-88)], male (68%), motorcyclists (76%), drove without licence (85%) and without insurance (95%). Most accidents occurred during evenings and Lao New Year. Serious motorbike injuries were associated with young age (1-15 years), male sex ( OR 2.2, 95% CI 1.1-4.6) and drivers ( OR 2.1, 95% CI 1.1-4.3); more serious head injuries with alcohol consumption ( OR 2.5, 95% CI 1.7-3.7), male sex ( OR 2.3, 95% CI 1.4-3.7) and no helmet use ( OR 2.0, 95% CI 1.2-3.4). No helmet use was associated with young age, time period, pillion passengers ( OR 2.7, 95% CI 1.6-4.7), alcohol ( OR 1.9, 95% CI 1.2-2.8) and no driver license ( OR 2.0; 95% CI 1.1-3.4). Main reasons not to wear helmets were not possessing one, and being pillion passenger. Capture-recapture analysis showed four times higher RTI estimates than officially reported. Mortality rate was 11.6/100.000 population (95% CI 5.1-18.1/100.000). Conclusions RTI were substantially underestimated. Combining hospital with police data can provide better estimates in resource-limited settings. Preventive programmes and law enforcement have to target male drivers, alcohol, licensing and helmet use, especially among children and pillion passengers. Increased efforts are needed during evening time and special festivals. [ABSTRACT FROM AUTHOR]

Background: Most countries have detailed lists of traffic rules and elaborate legal regimes for penalizing drivers who break them. Previous research has suggested that drivers tend to drive more safely after receiving penalties for traffic infringements.Methods: We linked driver-level data on infringements and crashes in Queensland, Australia (1995-2010) with information on the licence histories of all drivers in the state. We used a case-crossover design to examine drivers' risk of crashing in the month following an infringement penalty. We also examined whether changes in crash risk following infringement penalties varied according to driver age and gender, type of infringement and whether the offender was at fault in a subsequent crash.Results: Drivers had higher risks of crashes following infringement penalties [odds ratio (OR) 1.32; 95% confidence interval (CI) 1.29-1.36], especially crashes in which the offender was at fault (1.41; 1.36-1.46). Crash risk relative to a comparable period was particularly high for teenage drivers (1.55; 1.34-1.78) and among drivers penalized for dangerous driving (3.19; 2.52-4.03) or driving under the influence of alcohol (1.99; 1.67-2.37). The risk remained relatively high for more than 6 months after the penalty, but declined steadily over this period.Conclusions: Crash risk among drivers in Queensland was higher, not lower, following receipt of penalties for traffic infringements. Penalties themselves are unlikely to increase crash risk. A more likely explanation is that penalties (or the corresponding infringements) mark episodes of risky driving. Our findings suggest that such episodes trounce any deterrent effect penalties may produce. [ABSTRACT FROM AUTHOR]

Probabilistic analysis of traffic loading on a bridge traditionally involves an extrapolation from measured or simulated load effects to a characteristic maximum value. In recent years, long run simulations, whereby thousands of years of traffic are simulated, have allowed researchers to gain new insights into the nature of the traffic scenarios that govern at the limit state. For example, mobile cranes and low-loaders, sometimes accompanied by a common articulated truck, have been shown to govern in most cases. In this paper, the extreme loading scenarios identified in the long-run simulation are applied to a non-linear, two-dimensional (2D) plate finite element model. For the first time, the loading scenarios that govern in 2D nonlinear analyses are found and compared to those that govern for 2D linear and one-dimensional (1D) linear and nonlinear analyses. Results show that, for an isotropic slab, the governing loading scenarios are similar to those that govern in simple 1D (beam) models. Furthermore, there are only slight differences in the critical positions of the vehicles. It is also evident that the load effects causing failure in the 2D linear elastic plate models are significantly lower, i.e., 2D linear elastic analysis is more conservative than both 2D nonlinear and 1D linear and nonlinear analyses. [ABSTRACT FROM AUTHOR]

Many transportation agencies such as Departments of Transportation in the USA are using Asset Management Optimization models to plan their maintenance and rehabilitation projects. Currently available commercial solutions are often focused only on global asset performance/money spent aspect of the problem and do not take into account the benefits of synergy between the projects, i.e. the benefits of scheduling nearby projects in the same year in order to take advantage of fixed cost savings due to economies of scale. At the strategic level adding variables and constraints to account for these economies of scale are not practical since such models often already have millions of variables and constraints and adding anything new could reduce the performance significantly. Looking at the problem from a tactical perspective however it is possible to run an analysis on the global work plan that can improve cost savings from economies of scale with subtle changes to the originally analyzed performance. For example, in case of pavement management it is a common result to see gaps in the produced theoretical work plans along a route that would result in increased mobilizations to accomplish the plan. This results in extra costs both for the agency and road user. A common result might suggest fixing miles 1-8 and 9-10 in the one year and then fixing mile 8-9 in a subsequent year. Even if this solution provided the best performance for the money it is impractical to actually do it, it would make much more sense to simply fix entire 10 mile segment while achieving almost the same performance and saving mobilization costs which can be significant cost savings. A project coordination optimization model would analyze economies of scale problems such as these while also considering network constraints such as limited budgets and resources available within the administrative unit managing the work plan. This paper proposes an optimization model, referred to as Project Coordination model throughout the paper, that would attempt to improve an already created work plan by slightly changing the project schedules such that the adjusted plan would achieve similar performance while providing a more practical solution by maximizing economies of scale with reduced delivery and mobilization costs. The results of applying proposed model to one illustrative example and two real life work plans are presented and thoroughly analyzed. [ABSTRACT FROM AUTHOR]

Copyright of Baltic Journal of Road & Bridge Engineering (Baltic Journal of Road & Bridge Engineering) is the property of Baltic Journal of Road & Bridge Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper focused on modelling Black Carbon (BC) concentrations in two busy street canyons, the Crown and Belliard Street in Brussels. The used original Operational Street Pollution Model was adapted to BC by eliminating the chemical module and is noted here as CANS BC . Model validations were performed using temporal BC data from the fixed measurement network in Brussels. Subsequently, BC emissions were adjusted so that simulated BC concentrations equalled the observed ones, averaged over the whole period of simulation. Direct validations were performed for the Crown Street, while BC model calculations for the Belliard Street were validated indirectly using the linear relationship between BC and NO x . Concerning the Crown Street, simulated and observed half-hourly BC concentrations correlated well ( r = 0.74) for the period from July 1st, 2011 till June 30th, 2013. In particular, CANS BC performed very well to simulate the monthly and diurnal evolutions of averaged BC concentrations, as well as the difference between weekdays and weekends. This means that the model correctly handled the meteorological conditions as well as the variation in traffic emissions. Considering dispersion, it should however be noted that BC concentrations are better simulated under stable than under unstable conditions. Even if the correlation on half-hourly NO x concentrations was slightly lower ( r = 0.60) than the one of BC, indirect validations of CANS BC for the Belliard Street yielded comparable results and conclusions as described above for the Crown Street. Based on our results, it can be stated that CANS BC is suitable to accurately simulate BC concentrations in the street canyons of Brussels, under the following conditions: (i) accurate vehicle counting data is available to correctly estimate traffic emissions, and (ii) vehicle speeds are measured in order to improve emission estimates and to take into account the impact of the turbulence generated by moving vehicles on the local dispersion of BC. [ABSTRACT FROM AUTHOR]

Regulations of use of social networks, as one of the key components in these networks, serve an important role in controlling the flow of traffic. The study of the harmonization of these terms and regulations can be a significant step to avoid congestion and (Users') rejection in the network. Harmonization of traffic control regulations (TCR) among social networks is one of the best solutions to establish consequent traffic flow out of the network. Depending on the conditions, harmonization can be done in different ways. This article examines the direct pass and indirect pass methods. Node phase differences are key elements for harmonization of social networks considered in this review. To calculate the optimal phasing and appropriate phase difference, first the status of a user in the two social network samples has been analyzed using Gephi software, and then the results have been simulated by charting. In this article, the harmonization of traffic control regulations (TCR) was done based on evaluation of the TCR performance through determining the appropriate phase differences and reference rule and calculating the measurement of Latency (LT) in the main network port. This latency was calculated as the difference of the expected time and real time of connection or login to the network in simulated conditions. The achieved results indicate that in unsaturated conditions using indirect pass method and in saturated conditions, due to rejection of user and inability of network TCR, using indirect pass method is the best choice for harmonization of the TCR among social networks. [ABSTRACT FROM AUTHOR]

Short time prediction is one of the most important factors in intelligence transportation system (ITS). In this research, the use of feed forward neural network for traffic time-series prediction is presented. In this paper, the traffic in one direction of the road segment is predicted. The input of the neural network is the time delay data exported from the road traffic data of Monroe city. The time delay data is used for training the network. For generating the time delay data, the traffic data related to the first 300 days of 2008 is used. The performance of the feed forward neural network model is validated using the real observation data of the 301st day. [ABSTRACT FROM AUTHOR]

The object of this paper is to analyze and to suggest improvements on intersection management systems using existing equipment currently available in street intersections. In order to do this, we designed an intersection management system capable of detecting traffic violations as well as vehicle collisions using high-speed cameras. We propose to implement the above mentioned system through design and simulation in the LabVIEW programming environment. LabVIEW offers all the instrumentation necessary to accurately simulate the phenomena that occur in modern-day intersections, making it possible to further develop the existing intersection technology. It also makes it possible to determine the requirements and limitations of the existing equipment and to find the best solutions for every scenario. [ABSTRACT FROM AUTHOR]

The concept and structure of automatic management system of traffic movement in metropolitan areas is proposed by the authors, where the parameters of road network and efficient information on traffic streams are used as primary data as well as empirical-stochastic approach to simulation and forecast of development of situation.

In a traffic-aware route search (TARS), the user provides start and target locations and sets of search terms. The goal is to find the fastest route from the start location to the target via geographic entities (points of interest) that correspond to the search terms, while taking into account variations in the travel speed due to changes in traffic conditions, and the possibility that some visited entities will not satisfy the search requirements. A TARS query may include temporal constraints and order constraints that restrict the order by which entities are visited. Since TARS generalizes the Traveling-Salesperson Problem, it is an NP-hard problem. Thus, it is unlikely to find a polynomial-time algorithm for evaluating TARS queries. Hence, we present in this paper three heuristics to answer TARS queries-a local greedy approach, a global greedy approach and an algorithm that computes a linear approximation to the travel speeds, formulates the problem as a Mixed Integer Linear Programming (MILP) problem and uses a solver to find a solution. We provide an experimental evaluation based on actual traffic data and show that using a MILP solver to find a solution is effective and can be done within a limited running time in many real-life scenarios. The local-greedy approach is the least effective in finding a fast route, however, it has the best running time and it is the most scalable. [ABSTRACT FROM AUTHOR]

Abstract: Background: Increasing evidence suggests that ultrafine particles (UFPs) may contribute to cardiorespiratory morbidity. We examined the relationship between near road UFPs and several traffic and built environment factors to identify predictors that may be used to estimate exposures in population-based studies. Black carbon (BC) was also examined. Methods: Data were collected on up to 6 occasions at 73 sites in Montreal, Canada over 6-week period during summer, 2012. After excluding highly correlated variables, road width, truck ratio (trucks/total traffic), building height, land zoning parameters, and meteorological factors were evaluated. Random-effect models were used to estimate percent changes in UFP and BC concentrations with interquartile changes in each candidate predictor adjusted for meteorological factors. Results: Mean pollutant concentrations varied substantially across sites (UFP range: 1977–94, 798particles/cm3; BC range: 29–9460ng/m3). After adjusting for meteorology, interquartile increases in road width (14%, 95% CI: 0, 30), building height (13%, 95% CI: 5, 22), and truck ratio (13%, 95% CI: 3, 23) were the most important predictors of mean UFP concentrations. Road width (28%, 95% CI: 9, 51) and industrial zoning (18%, 95% CI: 2, 37) were the strongest predictors of maximum UFP concentrations. Industrial zoning (35%, 95% CI: 9, 67) was the strongest predictor of BC. Conclusions: A number of traffic and built environmental factors were identified as important predictors of near road UFP and BC concentrations. Exposure models incorporating these factors may be useful in evaluating the health effects of traffic related air pollution. [Copyright &y& Elsevier]

Background: Traffic-related air pollution (TRAP) is a major source of air pollution but the impact on health in Nigeria is not well described. Patients and Methods: A descriptive cross-sectional study of road traffic workers and university students in Lagos. Eligible, accessible and willing participants were included in the sample. Respiratory symptoms and anthropometry were obtained from all the participants using an adapted Medical Research Council (MRC) questionnaire and they all did a spirometry test and exhaled carbon monoxide (CO) test. Results: Fifty-nine individuals participated with complete data, including 47 traffic policemen and 12 students who acted as controls. The mean age (SD) was 35.1 (8.0) and 35.4 years (6.3) for the traffic workers and students, respectively. All the respondents were men. The mean (SD) duration of occupation as a traffic policeman was 4.4 (4.4) and a median of 4 years (range 1-25). There was no significant difference in the presentation of respiratory and non-respiratory symptoms between the two groups. Compared with the students, the traffic workers had higher age, height and sex adjusted forced expiratory volume in one second and forced vital capacity. Traffic policemen had significantly higher levels of exhaled CO than the students (1.18 vs 0.73 ppm, P < 0.006). Conclusion: There is a high prevalence of respiratory symptoms in both traffic policemen and non-traffic residents of Lagos metropolis, indicating widespread pollution. [ABSTRACT FROM AUTHOR]

This study applies artificial neural network (ANN) for the determination of optimized height of a highway noise barrier. Field measurements were carried out to collect traffic volume, vehicle speed, noise level, and site geometry data. Barrier height was varied from 2 to 5 m in increments of 0.1 m for each measured data set to generate theoretical data for network design. Barrier attenuation was calculated for each height increment using Federal Highway Administration model. For neural network design purpose, classified traffic volume, corresponding traffic speed, and barrier attenuation data have been taken as input parameters, while barrier height was considered as output. ANNs with different architectures were trained, cross validated, and tested using this theoretical data. Results indicate that ANN can be useful to determine the height of noise barrier accurately, which can effectively achieve the desired noise level reduction, for a given set of traffic volume, vehicular speed, highway geometry, and site conditions. [ABSTRACT FROM AUTHOR]

The negative impacts of urban traffic growth are well known, e.g., congestion, increased air pollution, and more traffic noise. Humans can readily see traffic congestion, and can hear traffic noise, but inevitably they are much less aware of odorless, invisible, silent air pollution. Therefore, quite naturally people, whether the general public or transport professionals, struggle to visualize air pollution from traffic, and will find it particularly difficult to visualize changes in air pollution levels resulting from changes in traffic conditions because of the implementation of various urban transport schemes. Hence, there is always a risk of the air quality impacts of potential urban transport schemes being underappreciated. Therefore, this paper contributes to the knowledge by devising a new three-dimensional (3D) visualization approach for modeled air quality before and after the implementation of potential urban transport schemes. Using the Dunkirk area of the City of Nottingham in the United Kingdom as a case study, research has been undertaken to integrate an air pollution dispersion model for the pollutant with a 3D digital city model. The modeled concentrations, before and after the implementation of an urban transport scheme, were represented in the 3D city model at various heights above the ground: first, as 3D point shapes; second, as 3D planar surfaces; and finally, as 3D volumetric clouds. The 3D volumetric clouds approach used the analogy of people's perceptions of gray clouds in the sky as representing undesirable weather, and hence provided an intuitive 3D visualization of all the modeled concentrations, at and above the ground surface, in a single 3D virtual scene. Benefits have been identified in enhancing the level of understanding of the pollution dispersion using this new approach to visualization. This has allowed the visualization process to be used in the development of future traffic scenarios that could be used to alter the design of a proposed transport scheme to increase its air quality benefits. This 3D visualization approach was found to be applicable to other transport schemes in different parts of the City of Nottingham. [ABSTRACT FROM AUTHOR]

Abstract: An integrated modelling approach is adopted to estimate microscale urban traffic emissions. The modelling framework consists of a traffic microsimulation model developed in PARAMICS, a microscopic emissions model (Comprehensive Modal Emissions Model), and two dispersion models, AERMOD and the Quick Urban and Industrial Complex (QUIC). This framework is applied to a traffic network in downtown Toronto, Canada to evaluate summer time morning peak traffic emissions of carbon monoxide (CO) and nitrogen oxides (NO x ) during five weekdays at a traffic intersection. The model predicted results are validated against sensor observations with 100% of the AERMOD modelled CO concentrations and 97.5% of the QUIC modelled NO x concentrations within a factor of two of the corresponding observed concentrations. Availability of local estimates of ambient concentration is useful for accurate comparisons of predicted concentrations with observed concentrations. Predicted and sensor measured concentrations are significantly lower than the hourly threshold Maximum Acceptable Levels for CO (31 ppm, ∼90 times lower) and NO2 (0.4 mg/m3, ∼12 times lower), within the National Ambient Air Quality Objectives established by Environment Canada. [Copyright &y& Elsevier]

The Traffic and Urban Mobility System (Sistema de Información de Tráfico y Movilidad Urbana - SITYMUR) is a tool used to collect positional data from circulating agents on the roads, in order to generate traffic and mobility information in near real time. This issue raises important technological challenges concerning communications, data processing and publication of the results. This article describes these challenges and discusses the effectiveness of solutions proposed by showing a number of traffic and speed results for Bogotá as well as suggesting possible alternatives for improvement. [ABSTRACT FROM AUTHOR]

The major objective of this paper is to examine the variations of injuries from road traffic accident in Lagos State. The study used mostly secondary data. The data where obtained for a period of thirty-two (32) years from 1970-2001. The 16 harmonies for the selected Local Government Areas considered contribute above 70% of the total variance in the time series. This means that more than 70% of injuries from road traffic accidents in Lagos State could be attributed to recklessness on the part of drivers, ignorance of high way codes, over speeding etc. Also, the dominant cycles of injuries from road traffic accidents observed in the study area have periodicities of 32.00 and 16.00 years with the most dominant being 32 years. Based on the findings, recommendations were proffered. [ABSTRACT FROM AUTHOR]

Community severance occurs where road traffic (speed or volume) inhibits access to goods, services, or people. Appleyard and Lintell's seminal study of residents of three urban streets in San Francisco found an inverse relationship between traffic and social contacts. The extent of social networks predicts unhealthy behaviors, poor health, and mortality; high rather than low social integration is associated with reduced mortality, with an effect size of similar magnitude to stopping smoking. Although community severance diminishes social contacts, the implications of community severance for morbidity and mortality have not been empirically established. Based on a systematic literature search, we discuss what is actually known about community severance. There is empirical evidence that traffic speed and volume reduces physical activity, social contacts, children's play, and access to goods and services. However, no studies have investigated mental or physical health outcomes in relation to community severance. While not designed specifically to do so, recent developments in road design may also ameliorate community severance. [ABSTRACT FROM AUTHOR]

Buildings in the proximity of roads can be affected by vibrations induced by traffic. Local geological pattern is necessary to be taken into account because it has significant influence on values of vibrations and their characteristics. This paper summarizes results of experimental measurements. Four different types of buildings in different types of local geology were used for this purpose. The obtained results document that the generation of significant vibrations is mostly due to heavy vehicles. Some maximum velocity values exceed acceptable limits according to the Czech Technical Standard 73 0040 for evaluation of technical seismicity effect on buildings. Cosmetic damage, meaning the cracking of plaster, might occur due to traffic vibrations. [ABSTRACT FROM AUTHOR]

Abstract: Ground vibrations due to road traffic constitute a major environmental problem. This paper presents a numerical model for the analysis and prediction of the ground vibrations due to the road traffic. A car model with four degrees of freedom is used for the determination of the load due to the road traffic. The load is then introduced in a 3D finite difference model for the determination of the traffic-induced ground vibrations. The numerical model is validated using field data. Numerical analyses show that both the amplitude and frequency of the traffic-induced vibrations are mainly affected by the vehicle speed, the road unevenness and the vehicle suspension system. Some recommendations are suggested for the reduction of these vibrations. [Copyright &y& Elsevier]

The design of the building that is going to hold the operations to pick-up the female students by private vehicles when classes are finished is presented for an Arabian university. The premises have been designed to maximize the capacity of the parking arrangement and maintain a constant and quick flow of vehicles within complex sociological constraints. Architects, traffic engineers and simulation specialists have concurrently designed a building that has to give service to 4500 vehicles within 1 h. The solution is based on three pillars: just-in-time, to simplify the tasks and laminate the demand so the flow rates are evenly distributed; information technologies, to maximize the probability of the students being ready when the corresponding vehicle arrives; and discrete-event simulation to abstract the complex procedures in a realistic, dynamic way and to visualize the movement so as to transmit credibility on the selected design to all the parties involved. [ABSTRACT FROM AUTHOR]

Abstract: Air pollution is a common problem in mega-cities in Asia, resulting in high levels of particulate matter (PM). In this study, 24 h samples of airborne particulate matter (PM2.5 and PM10) was collected for two weeks in urban locations in Kabul and Mazar-e Sharif, Afghanistan. The samples were analyzed for twenty n-alkanes, fifteen polycyclic aromatic hydrocarbons (PAHs) and eighteen oxygenated PAHs (oxy-PAHs). The results were compared to a reference location in Umeå, Sweden. The main objectives were: to characterize the organic fraction in PM2.5, with focus on oxy-PAHs, PAHs and n-alkanes, assess relationships between compound groups, and investigate possible source categories. Mean PM10, levels were 260 μg m−3, and 334 μg m−3 and mean PM2.5 levels were 86 μg/m3and 68 μg m−3 in Kabul and Mazar-e Sharif, respectively. The higher ratio of PM2.5 to PM10 in Kabul than Mazar-e Sharif or Umeå was reflected in the high number of small particles, as collected by a particle counter. Kabul and Mazar-e Sharif had high levels of PAHs and oxy-PAHs compared to Umeå and previously reported data from Western countries. Generally, the highest individual levels of oxy-PAHs were found for ketones (0.27–33 ng m−3), whereas the quinone levels were lower (0.027–3.1 ng m−3). High correlations (r > 0.96) between PAHs and oxy-PAHs were found at both locations. Diagnostics for n-alkanes, such as the carbon preference index, and the most abundant species, C max, and the presence of unresolved complex mixture indicated a higher contribution from coal and petroleum sources in Kabul. Models generated by principal component analysis (PCA) and positive matrix factorization (PMF) both suggested separate sources for lower molecular weight n-alkanes and higher molecular weight n-alkanes. The PAHs and the oxy-PAHs were not separated in either the PCA or the PMF models, indicating that they had similar sources and are perhaps relatively unspecific as source markers. Nevertheless, the PAHs and oxy-PAHs were good markers for bad air quality in the urban locations in Afghanistan in comparison to data from Western countries. Based on the models and diagnostic ratios it is suggested that traffic and combustion of coal and biomass were the dominating sources of the high levels of particle-bound organic compounds. [Copyright &y& Elsevier]

Abstract: Introduction: A common contention is that the construction of highway bypasses negatively impacts the economy of local communities by reducing pass-by traffic for businesses. However, as access to specific business'' account records is limited, this impact is difficult to quantify. Another common contention is that bypasses contribute to a reduction in overall crashes in the community and in the surrounding areas. Even though a large number of bypasses have been constructed in the State of Iowa over the past several years, their actual impact in terms of traffic safety has not been quantified. Objectives: This study seeks answers to the following questions: (a) Are bypasses in Iowa associated with a reduction in crash frequencies and crash rates on the bypassed highway? (b) Do bypasses in Iowa introduce a reduction of overall crash frequencies and rates or do they merely shift crashes from the highways through the communities to the bypasses with no significant overall reduction? Method: We obtained crash information from the Iowa DOT at 19 sites on which a bypass was constructed sometime during the past 23years. We also obtained the same information at six sites used as comparison sites on which no bypasses were constructed at least until 2005. We them employed a Bayesian approach to estimating the association between the construction of the bypass and crash rates, while also accounting for other factors. Results: The construction of bypasses in Iowa is associated with a significant increase in traffic safety both on the main road through town and on the combined main road and bypass roadway. [Copyright &y& Elsevier]

Abstract: Time–activity patterns are an important determinant of personal exposure to air pollution. This is demonstrated by measuring personal exposure of 16 participants for 7 consecutive days: 8 couples of which one person was a full-time worker and the other was a homemaker; both had a very different time–activity pattern. We used portable aethalometers to measure black carbon levels with a high temporal resolution and a PDA with GPS-logger and electronic diary. The exposure to black carbon differs between partners by up to 30%, although they live at the same location. The activity contributing most to this difference is transport: Average exposure in transport is 6445 ng m−3, followed by exposure during shopping (2584 ng m−3). Average exposure is lowest while sleeping (1153 ng m−3) and when doing home-based activities (1223 ng m−3). Full-time workers spend almost twice as much time in transport as the homemakers. As a result of the study design we measured in several different homes, shops, cars, etc. enabling a better insight in true overall exposure in those microenvironments. Other factors influencing personal exposure are: background concentrations and location of residence in an urban, suburban or rural environment. [Copyright &y& Elsevier]

This paper describes a new approach that allows us to partition the anthropogenic and natural contributions to heavy metal accumulations in roadside agricultural soils. This approach, combining trend analysis and multivariate statistical analysis, partitions total heavy metals into three components: anthropogenic, natural, and unexplained residual. The approach was applied in a case study in Yixing City, China, to determine the spatial distributions of heavy metal accumulations. The results show that anthropogenic components of Pb, Cu, Zn, and Cd account for 52.4%, 23.04%, 5.09%, and 10.9% of total content, respectively. Spatial distributions of anthropogenic components are characterized by decreasing accumulation with increasing distance from the road. Ranges of influence of traffic for Pb, Cu, and Cd are beyond 300 m, whereas the range of Zn is less than 200 m. The spatial distributions of the four elements' natural components show relatively similar distribution patterns. Assessments of variable partition methods show that the predicted values of Pb, Cu, Zn, and Cd are consistent with their measured values. The anthropogenic components extracted from total contents of heavy metal will be useful for modeling heavy metal accumulations produced by human activities. [ABSTRACT FROM AUTHOR]

In this paper, we developed a methodological framework to deal with traffic-stream modeling based on data mining, steepest-ascend algorithm, and genetic algorithm. The new method is adaptive in nature and has a greater flexibility and generality compared with existing methods. It provides an optimum overall fitting of the observed data. Specifically, the advantages of adaptive regression are that (1) knot positions and model parameters are estimated optimally and simultaneously using genetic algorithm, and presetting of knot positions can be performed in terms of either density or speed; (2) the method is automatic and data driven, and it will always find out the best fitting model to site-dependent actual traffic data; and (3) the user has a great flexibility to specify the degree-model continuity and to define and add new basis functions that are parsimonious and fit better into the traffic data in some regime of speed-density relation. The proposed method and developed computer software package MiningFlow will be beneficial to traffic operations and traffic simulation. [ABSTRACT FROM AUTHOR]

Traffic-generated air pollution and noise have both been linked to cardiovascular morbidity. Since traffic is a shared source, there is potential for correlated exposures that may lead to confounding in epidemiologic studies. As part of the Multi-Ethnic Study of Atherosclerosis and Air Pollution (MESA Air), 2-week NO and NO2 concentrations were measured at up to 105 locations, selected primarily to characterize gradients near major roads, in each of 9 US communities. We measured 5-min A-weighted equivalent continuous sound pressure levels (L eq) and ultrafine particle (UFP) counts at a subset of these NO/NO2 monitoring locations in Chicago, IL (N=69 in December 2006; N=36 in April 2007) and Riverside County, CA (N=46 in April 2007). L eq and UFP were measured during non-“rush hour” periods (10:00–16:00) to maximize comparability between measurements. We evaluated roadway proximity exposure surrogates in relation to the measured levels, estimated noise–air pollution correlation coefficients, and evaluated the impact of regional-scale pollution gradients, wind direction, and roadway proximity on the correlations. Five-minute L eq measurements in December 2006 and April 2007 were highly correlated (r=0.84), and measurements made at different times of day were similar (coefficients of variation: 0.5–13%), indicating that 5-min measurements are representative of long-term L eq. Binary and continuous roadway proximity metrics characterized L eq as well or better than NO or NO2. We found strong regional-scale gradients in NO and NO2, particularly in Chicago, but only weak regional-scale gradients in L eq and UFP. L eq was most consistently correlated with NO, but the correlations were moderate (0.20–0.60). After removing the influence of regional-scale gradients the correlations generally increased (L eq–NO: r=0.49–0.62), and correlations downwind of major roads (L eq–NO: r=0.53–0.74) were consistently higher than those upwind (0.35–0.65). There was not a consistent effect of roadway proximity on the correlations. In conclusion, roadway proximity variables are not unique exposure surrogates in studies of endpoints hypothesized to be related to both air pollution and noise. Moderate correlations between traffic-generated air pollution and noise suggest the possibility of confounding, which might be minimized by considering regional pollution gradients and/or prevailing wind direction(s) in epidemiologic studies. [Copyright &y& Elsevier]

Few studies investigate the impact of air pollution on the leading cause of infant morbidity, acute bronchiolitis. We investigated the influence of PM2.5 and other metrics of traffic-derived air pollution exposure using a matched case–control dataset derived from 1997 to 2003 birth and infant hospitalization records from the Puget Sound Region, Washington State. Mean daily PM2.5 exposure for 7, 30, 60 and lifetime days before case bronchiolitis hospitalization date were derived from community monitors. A regional land use regression model of NO2 was applied to characterize subject''s exposure in the month prior to case hospitalization and lifetime average before hospitalization. Subject''s residential proximity within 150m of highways, major roadways, and truck routes was also assigned. We evaluated 2604 (83%) cases and 23,354 (85%) controls with information allowing adjustment for mother''s education, mother''s smoking during pregnancy, and infant race/ethnicity. Effect estimates derived from conditional logistic regression revealed very modest increased risk and were not statistically significant for any of the exposure metrics in fully adjusted models. Overall, risk estimates were stronger when restricted to bronchiolitis cases attributed to respiratory syncytial virus (RSV) versus unspecified and for longer exposure windows. The adjusted odds ratio (ORadj) and 95% confidence interval per 10mcg/m3 increase in lifetime PM2.5 was 1.14, 0.88–1.46 for RSV bronchiolitis hospitalization. This risk was also elevated for infants who resided within 150m of a highway (ORadj 1.17, 0.95–1.44). This study supports a developing hypothesis that there may be a modest increased risk of bronchiolitis attributable to chronic traffic-derived particulate matter exposure particularly for infants born just before or during peak RSV season. Future studies are needed that can investigate threshold effects and capture larger variability in spatial contrasts among populations of infants. [Copyright &y& Elsevier]