Median Strip Research Articles

Impact of Median Separation Facilities on Drivers’ Shy-Away Effects: Why Are Median Separation Facilities Widely Used in China?

In recent years, China has begun introducing readily installable median separation facilities into its urban road network. Although some studies have recognized the benefits of using median separation, few have investigated the effects of different types of facilities on driver behavior. This driving simulator study aims to determine whether different types of medians on urban arterial roads in China affect driving behavior, and to provide new insights for designing more effective and safer forms of median separation. A driving simulator study was conducted, with 50 participants. The scenario exactly reproduced an existing six-lane urban arterial road in China, and four different median separation types were tested: (1) double yellow line; (2) raised pavement markers; (3) reboundable traffic cylinders; (4) traffic separator railing. Their effects were statistically analyzed using data on driver eye movements, trajectories, and speeds collected from simulation tests. The results showed that the median separation facilities significantly improved drivers’ access to road information, corrected drivers’ attention, and suppressed driving speeds. Although median separation facilities can be an effective solution to the current problem of chaotic vehicular traffic on China’s urban roads, their setup still needs to be optimized. This study demonstrates the calculation method for optimal median facility setup. The resulting 1.21-m-high median facility, paired with a 1.17-m-wide median strip and a certain lane-width compression, more effectively addresses driver factors, the driving task, and the spatial right-of-way. The study’s calculations can also be used to improve other types of roads that can take a median separation facility.

Evaluating mechanical benefit of wedge osteotomies in endoscopic surgery for sagittal synostosis using patient-specific 3D-printed models.

Endoscopically assisted sagittal strip craniotomy with subsequent cranial orthosis is a frequently used surgical approach for non-syndromic sagittal synostosis. Originally, this technique involved a wide sagittal strip craniectomy with bilateral wedge osteotomies. More recent studies suggest omitting wedge osteotomies, achieving similar outcomes. The controversy surrounding wedge osteotomies and our efforts to refine our technique led us to create models and evaluate the mechanical impact of wedge osteotomies. We conducted a 3D-print study involving preoperative CT scans of non-syndromic scaphocephaly patients undergoing minimally invasive-assisted remodelation (MEAR) surgery. The sagittal strip collected during surgery underwent thickness measurement, along with a 3-point bending test. These results were used to determine printing parameters for accurately replicating the skull model. Model testing simulated gravitational forces during the postoperative course and assessed lateral expansion under various wedge osteotomy conditions. The median sagittal strip thickness was 2.00mm (range 1.35-3.46mm) and significantly positively correlated (p = 0.037) with the median force (21.05 N) of the 3-point bending test. Model testing involving 40 models demonstrated that biparietal wedge osteotomies significantly reduced the force required for lateral bone shift, with a trend up to 5-cm-long cuts (p = 0.007). Additional cuts beyond this length or adding the occipital cut did not provide further significant advantage (p = 0.1643; p = 9.6381). Biparietal wedge osteotomies reduce the force needed for lateral expansion, provide circumstances for accelerated head shape correction, and potentially reduce the duration of cranial orthosis therapy.

Study of the necessity of a speed monitoring display at the returning chicane on a freeway bypass

Objective Roadwork zones represent a hazardous place within the highway system, with higher crash rates and injury severity, often due to excessive speed and noncompliance with speed limits. On freeways, a common layout is to close a full roadway and to divert traffic onto the opposite roadway, with one lane closed to accommodate the redirected traffic, by driving through the median strip. In this scenario, the second chicane can be a hazardous point if it is not correctly signaled. This paper examines the need to install a speed monitoring display (SMD) before the returning chicane on a bypass. Methods A two-phase study was conducted on a Spanish freeway where a roadway was temporarily closed. Two measurement points were established on the bypass, one in the middle and one at the end, prior to the return chicane through the median strip. During Phase 1, the portable SMD was installed and during Phase 2, it was removed. The average and the 85th percentile of the speed distribution at each point during both phases were compared. Additionally, mean difference tests were conducted and a speed prediction model was developed. Results With the SMD, drivers reduced their speed from the midpoint to the returning chicane, within the range of 7-10 km/h. Conversely, upon removal of the SMD, motorists increased their speed while driving through the bypass, resulting in excessive speed at the most hazardous point, the chicane leading back to the original roadway. The difference in mean speed between the two phases was 18 km/h at the returning chicane. Conclusions In addition to the traffic calming measures implemented prior to entering roadwork zones on freeways, which are conveniently established in the standards; it is necessary to evaluate potentially dangerous areas of the layout and implement additional measures where required. Specifically, in the case of final chicanes of bypasses with reduced radii, it is recommended that a speed monitoring display be installed as a mandatory element in order to inform drivers of this challenging segment. Highway administrations around the world should maintain a SMD at the returning chicane of a bypass while roadworks last.

Potentials for Optimizing Roadside Greenery to Improve the Quality of Life in Cities

Trees and plants at the roadside or on median strips are called roadside greenery. These are not only beautiful in our environment but are also an important component of the biological system of a city. In addition, roadside greenery provides a variety of design, structural, traffic and ecological functions. These include shading and aesthetics, but also the sense of security and as a measure against the consequences of climate change. Worldwide, more and more people are living in cities and urbanization is steadily increasing. As a result, inner-city development is becoming increasingly dense, and the air is getting worse. In order to make people’s living environments as pleasant and healthy as possible, more greenery is needed in cities. In this research work, the relationship between quality of life and street greenery is investigated. The aim is to analyze the different needs and wishes of citizens and to identify and compile positive consequential effects of street greenery on people and the environment, as well as possible deficits in urban areas. A guideline for action with recommendations will support municipalities in upgrading and expanding street greenery in cities. The empirical study shows that street greenery is enormously important for the general and subjective quality of life for every age group. The perception of the population shows different assessments and ideals regarding street greenery. Overall, there is a desire among the population to maintain and optimize street greenery in the city.

Spatial Green Space Assessment in Suburbia: Implications for Urban Development

Nonthaburi, a suburban province adjacent to the Bangkok Metropolis, has experienced a reduction in green spaces due to urban expansion. This study quantified Nonthaburi’s green space through visual interpretation of land use and land cover (LULC) using THEOS and Sentinel-2. Areas of green space were extracted using remote sensing indices and pixel-based classification based on THEOS. The extracted green area was then integrated with the existing LULC patterns to align with the green space characteristic established by Thailand’s Office of Natural Resource and Environmental Policy and Planning. This includes public services, functional utility, median strips, community economics, fallow, and natural green space. The analysis of green space management and planning utilized the Urban Green Space Index (UGSI), Per Capita Green Space (PCGS), and accessibility to public green space. The results revealed that Nonthaburi comprises a green space area of 465.29 km2 or 73.06%, exhibiting a higher prevalence within its western region while displaying a relatively lower extent in the urban zone adjacent to the Bangkok Metropolis. The per capita green space is 367.71 m2 but decreases to 255.82 m2 when accounting for the latent population, meaning it still meets the World Health Organization (WHO) criteria. Currently, only six parks (single and clusters) meet the criteria for public green space. Additionally, both fallow and median strip green spaces (at road interchanges) need to be considered for their potential use in new public service. Furthermore, very high-resolution imagery from unmanned aerial vehicles (UAVs) should be used for green space planning by the organization.

A Study on the Analysis of Law Violation Data for the Creation of Autonomous Vehicle Traffic Flow Evaluation Indicators

The study analyzes the reason for the steady increase in the number of traffic accidents in Yongin City, Gyeonggi-do, despite the improvement of Korea's traffic accident system and the decrease in the number of traffic accidents. Seven years of traffic accident data is collected to analyze major legal violations and accident risks and to derive accident-prone areas and road risk indices through QGIS mapping. Based on this analysis, it identifies the causes of accidents in multiple accident areas, proposes improvement measures like the installation of a median strip and an unmanned traffic control device near a crosswalk, and emphasizes the significance of driver awareness and safety education. The aim of the study is to analyze road risk factors and suggest improvement measures to prevent traffic accidents, with the goal of improving the traffic situation in Yongin city.

Revision of Xiphentedon Risbec, 1957 and Colpixys Waterston, 1916 (Hymenoptera, Eulophidae), with descriptions of new species from the Afrotropics

The genera Colpixys and Xiphentedon are revised. Both genera are of Afrotropical distribution and are very similar to Entedon, but distinguished by a median strip or furrow on the propodeum replacing the median carina of Entedon. The genus Xiphentedon is characterized by the complete lateral propodeal sulci delimiting convex submedian areas, prosternum with a flange, axillula with indentate projection, and densely hairy central mesopectus. The subgenus Cederholmia Gumovsky, 1997 of Entedon is considered a junior synonym of Xiphentedon, so two of its species are moved to the genus as X. halli (Gumovsky, 1997) comb. nov. and X. danielssoni (Gumovsky, 1997) comb. nov. The genus Colpixys is characterized by the lack of characters of Xiphentedon, but also by the broadly sculptured propodeum with the deep median furrow delimited laterally by two sinuous margins. Three (one new) species are recognized in Colpixys and sixteen (thirteen new) species allocated to three groups (kayovei, danielssoni and forceps), are assigned to Xiphentedon. The new species are: Colpixys eburnus sp. nov. from Ivory Coast and the Republic of South Africa (RSA), Xiphentedon neserorum sp. nov. from RSA, X. simoni sp. nov. from Tanzania, X. dewittei sp. nov. and X. musimba sp. nov. from the Democratic Republic of the Congo (DRC), X. jeanyvesi sp. nov. from Tanzania, the Central African Republic (CAR) and RSA, X. wieringai sp. nov. from Gabon and Ivory Coast, X. kivuensis sp. nov. from DRC, X. palabora sp. nov. from RSA, X. sangha sp. nov. from CAR, X. nimba sp. nov. from Guinea, X. forceps sp. nov. from Ivory Coast, Benin and RSA, X. gerardi sp. nov. from Benin, DRC and RSA, and X. acutigena sp. nov. from Ivory Coast, DRC, Tanzania and RSA. Morphological peculiarities and possible relationships of Colpixys, Xiphentedon, Entedon and some other genera, are discussed.

Ultimate Load-Bearing Capacity of Rigid Two-Way Pavements Placed on Geosynthetic-Supported Soil Embankment

This study investigates the ultimate load-bearing capacity of rigid two-way concrete pavements placed on conventional and reinforced soil embankments using upper-bound limit analysis (UBLA). In the presence of the median strip, upper-bound solutions of rigid pavements resting on reinforced embankments did not draw much attention from previous researchers. Therefore, a rigorous UBLA is performed, adopting the multi-block failure mechanism for the intended purpose. The true upper-bound solution is achieved by satisfying the conditions of geometric compatibility and kinematic admissibility. The effects of the proximity of dual carriageways and embankment slopes on the load-bearing capacity of pavements are expressed in relation to interaction factors. The critical spacing beyond which the proximity effect ceases to exist is estimated for different slope angles of the embankment. A parametric investigation is performed to understand the influence of various soil parameters, embankment geometry, and layers of reinforcement. A notable improvement in the performance of two closely spaced rigid pavements can be observed by providing additional layers of reinforcement. The current outcomes are sensible and match well with the existing investigations.

EVALUASI KINERJA SIMPANG TAK BERSINYAL TIPE 422 DAN TIPE 424M (STUDI KASUS : SIMPANG EMPAT TAK BERSINYAL JALAN TGH IBRAHIM KHOLIDI, KECAMATAN KEDIRI, KABUPATEN LOMBOK BARAT)

The unsignalized four-way intersection in Kediri is located in the Kediri Subdistrict of West Lombok Regency and is one of the unsignalized intersections situated very close to the center of community activities. Additionally, there is an educational center in the vicinity, and the traffic conditions at this intersection are quite congested on a daily basis. The mobility level of both individuals and goods, using both light and heavy vehicles, is visibly high at this intersection. A median strip is the central part of the road that physically separates opposing traffic flows. Therefore, the use of a median strip on the road significantly impacts traffic flow efficiency, by reducing delays, queue probabilities, side hindrances, decreasing accident rates, and providing comfort for road users, thereby making road users feel safe and organized. Thus, the government is planning to construct a road median.This study analyzes the performance of an unsignalized intersection before and after the installation of a median, covering aspects such as volume, side constraints, queue probabilities, delays, and saturation levels, using the 1997 Indonesian Highway Capacity Manual (MKJI) methodology.The analysis results for the unsignalized intersection before median installation show a capacity of 3061.5 vehicles per hour, a saturation level of 0.970 (Service Level D), a delay of 14.885 seconds per vehicle, a queue probability of 36.361%, and side constraints amounting to 881.9 incidents per hour. On the other hand, for the unsignalized intersection tipe after median installation, it exhibits a capacity of 3330.5 vehicles per hour, a saturation level of 0.729 (Service Level C), a delay of 12.654 seconds per vehicle, a queue probability of 21.942%, and side constraints amounting to 629.2 incidents per hour.The performance of the four-way intersection in Kediri on TGH Ibrahim Kholidi Road, in the Kediri Subdistrict of West Lombok Regency, was lower before the median installation compared to the tipe of intersection after median installation.

Small urban fragments maintain complex food webs of litter-dwelling arthropods in a subtropical city in China

Urbanization-induced environmental changes such as habitat fragmentation impact arthropod assemblages and food web-related ecosystem functions, such as nutrient cycling and energy fluxes. Yet, we lack insight into how arthropod food webs are structured along urban fragmentation gradients. Here, we investigated the community composition and food web structure of litter-dwelling arthropods along fragmentation gradients (green median strip, i.e. green fragments in the middle of roads, urban park, urban forest and natural forest) in Xiamen City, southeast China. We found the density of litter-dwelling arthropods in median strips and urban parks to be two to four times higher than in urban and natural forests, with, as indicated by literature-based stable isotope values, 67%–68% of the individuals comprising primary consumers (trophic level I). Consequently, more complex food webs were found in small urban fragments (i.e., green median strip and urban park) than in the other fragments studied, including higher linkage density and higher energy flux. The biomass of litter on the floor was significantly correlated with the density of arthropods of trophic levels I, III and IV, and each trophic guild positively correlated with each other pointing to the dominance of bottom-up forces. Overall, our results suggest that small urban fragments maintain a high density of arthropods forming complex food webs and thereby may contribute to maintaining high energy fluxes and providing important ecosystem functions in urban areas.

A new species of Otostigmus (Chilopoda, Scolopendromorpha, Scolopendridae) from China, with remarks on the phylogenetic relationships of Otostigmuspolitus Karsch, 1881.

Through a combination of morphological and DNA data, a new scolopendrid centipede from southern and southwestern China was revealed: O.tricarinatussp. nov. The species belong to the politus group but has three sharp tergal keels. Validation of phylogenetic status was performed through molecular analysis of the cytochrome c oxidase subunit I (COI), 16S rRNA, and 28S rRNA sequences from 16 Otostigmus species. Otostigmustricarinatussp. nov. was found to be two populations and varied in the number of spines on the ultimate prefemur, the sutures on a sternite, and a pore-free median longitudinal strip in the pore field. The Yunnan-Guizhou plateau population of O.tricarinatussp. nov. was sister to the clade O.polituspolitus + O.politusyunnanensis + Guangxi population of O.tricarinatussp. nov. with strong support from both BI (bayesian inference) and ML (maximum likelihood) analyses (PP = 1, BS = 97%).

Grass from Road Verges as a Substrate for Biogas Production

Maintenance of urban green infrastructure generates a large amount of biomass that can be considered a valuable feedstock for biogas production. This study aims to determine the effect of the cutting time and method of substrate preservation on the specific methane yield (SMY) of urban grass collected from road verges and median strips between roadways in wet (WF) and dry fermentation (DF) technology. The grass was collected three times in a growing season, including in spring, summer, and autumn. The biochemical methane potential (BMP) test was performed on fresh grass, grass ensiled without additives, and grass ensiled with microbiological additives. In addition, the energy potentially produced from biogas and the avoided CO2 emissions were calculated. The highest SMY (274.18 ± 22.59 NL kgVS−1) was observed for the fresh grass collected in spring and subjected to WF. At the same time, the lowest CH4 production (182.63 ± 0.48 NL kgVS−1) was found in the grass ensiled without additives, collected in summer, and digested in DF technology. A comparison of the SMY obtained from the same grass samples in the WF and DF technologies revealed that higher CH4 yields were produced in WF. The electricity and heat production were affected by the time of grass cutting, ensilage method, and AD technology. Generally, less electricity but more heat was produced in DF technology. The least electricity (469–548 kWh tDM−1) was produced from the grass cut in spring and subjected to DF, while the most electricity (621–698 kWh tDM−1) was obtained from the grass collected in autumn and subjected to WF. In the case of heat production, the situation was reversed. The least heat (1.4–1.9 GJ tDM−1) was produced by the grass collected in spring and subjected to WF, while the most heat (2.2–2.7 GJ tDM−1) was produced by the grass collected in autumn and subjected to DF. Ensilage decreased the electricity and heat production in almost all the cuttings. The total reduction in CO2 emissions may amount to 2400 kg CO2 per 1 hectare of road verges. This significant reduction demonstrates that the use of grass from roadside verges in biogas plants should be considered a feasible option. Even though urban grass should be considered a co-substrate only, it can be a valuable feedstock that may partially substitute energy crops and reduce the area needed for energy purposes. Our results reveal that biogas production from the grass waste in WF technology is a stable process. The cutting time and preservation method do not affect the AD process. In DF technology, fresh grass, especially from the late growing season used as feedstock, extends the time of biomass decomposition and, therefore, should be avoided in a real-life biogas plant.

Generating citywide street cross-sections using aerial LiDAR and detailed street plan

Precise information on spatial configurations of urban spaces, such as streets, is essential for investigating complex interrelationships between the quality of life, livability, and mobility. Street cross-sections can be central for such research as they depict the allocation of urban space by detailing the streetscape's layout and dimensions, including driveways, sidewalks, bikepaths, median strips, trees, adjoining buildings and open spaces, and shadows. However, creating an accurate description of the real world as a three-dimensional representation and translation into cross-sections is challenging due to the requirement of multiple data sources, such as road layouts with widths, height information, and, optionally, high-resolution aerial imagery. Without such datasets, the cross-section drawings are limited to manual measurements, which are difficult to extend to a city scale. This study aims to develop a method to automatically generate street cross-sections for the entire city of Berlin based on an aerial Lidar dataset and a city street plan. The study also includes shadows as a part of the sections and utilizes the Lidar dataset to generate solar radiation maps. Approximately 0.5 million cross-sections are generated with detailed information regarding the width and placement of the street elements. The details of the cross-sections are further processed to find generic street compositions, understand the influence of shadows on walkways and bikepaths, and calculate the enclosure.

Autonomous vehicles and street design: Exploring the role of medians in enhancing pedestrian street crossing safety using a virtual reality experiment

As traffic lanes and on-street parking spots can potentially be downsized with the introduction of autonomous vehicles (AVs), the possibility of additional spare road space becoming available arises in future urban streets. While discussions on converting the leftover space into pedestrian-friendly alternatives exist, allocating that limited space to which alternative is foreseen to be another practical issue shared in both urban and transportation planning. However, evidence-based guidance on the issue provided from the actual verification on whether or to what extent the proposed alternatives may have an effect seems to be absent. Therefore, with an emphasis on pedestrian safety, this study focused on the “median strip” alternative as a first example and, through a VR simulation experiment aimed at empirically examining its suggested role on enhancing street crossing safety and further exploring its possible influence on pedestrians’ trust toward autonomous driving. With 99 participants, perceived safety (individual assessments of safety), performance-based safety (crossing success/abandonment and collision occurrence), and trust were either questioned or recorded for nine scenarios with varying crossing conditions. A combination of multilevel models and cross-tabulation results indicate that medians seem especially significant in ensuring the performance-based safety results of pedestrians even when AVs are driving at high speeds or with smaller gaps, thus suggesting it a win–win option for both. Insights and implications on the role and management of medians in future streets are further provided.

Assessment of greenery in urban canyons to enhance thermal comfort & air quality in an integrated seasonal model

The effect of green space in improving the air quality and thermal comfort of urban canyons has been investigated in many pieces of research. However, most were limited regarding the date, the experiment's duration, or the phenomenon under investigation. This study investigates different greenery patterns(type and position) in urban canyons and their effects on air pollution and thermal comfort to find optimal overall patterns.The effect of patterns in seasons, different urban canyons ratios, and greenery's aesthetical, cultural, and social aspects was considered. Numerical simulations and wind flow modeling were performed in the ENVI-met software. The results show that coniferous trees on sidewalks have the weakest, and Deciduous trees in the median strip alone can have the most favorable effect on improving air quality and thermal comfort in different seasons. Moving deciduous trees from the sidewalks to the median strip has reduced air pollution by 67% in summer and 54% in winter at the pedestrian level.

Effects of Road Components and Roadside Vegetation on Temperature Reduction in Seoul Considering Air, Wet-Bulb Globe, and Surface Temperatures

Urbanization has resulted in high temperatures in cities, which are exacerbated by an increase in urban impervious surfaces (road space). This study investigated the effect of urban road characteristics on roadside temperature. Different temperature indices were measured at four sites in Seoul with different road designs by using weather measuring devices and infrared thermal cameras. The differences between air and roadside air temperatures decreased from site 1 (no vegetation) to site 4 (roadside trees and vegetated medians). The analysis results showed that roadside wet-bulb globe and surface thermal temperatures sensitively changed according to road characteristics, unlike air temperature. The lowest temperatures were consistently observed at site 4. This cooling tendency was the strongest in the afternoon, which indicates the effectiveness of vegetation for preventing the commonly observed temperature rise in the afternoon. That is, roadside trees and vegetation in the median strip can prevent temperature rise and contribute to urban temperature reduction. Therefore, more roadside trees and median planting, as well as taller trees and denser vegetation along roads, can be used to provide a greater reduction of roadside temperatures and to improve urban climates.

Crash/Near-Crash Analysis of Naturalistic Driving Data Using Association Rule Mining

This study explores the associations between crash/near-crash (C/NC) events and roadway, driver-related, and environmental factors in naturalistic driving studies (NDS). We used the Naturalistic Engagement in Secondary Tasks (NEST) dataset, which is massive and detailed and contains 50 million miles of naturalistic driving data resulting from the Strategic Highway Research Program 2 (SHRP2). Association rule mining (ARM) is applied to extract the rules for frequently occurring events. The generated association rules are filtered by four metrics (support, confidence, lift, and conviction) and validated by the lift increase criterion. A three-step analysis is performed to obtain a comprehensive understanding of the rules of C/NC events. The 20 most frequent items are first selected to investigate their relationship with the C/NC events. Subsequently, the association rules are used to identify the factors contributing to C/NC events. Finally, correlations between contributing factors and different severities of crashes (I—most severe, II—police-reportable, III—minor crash, and IV—low-risk tire strike) are analyzed by ARM. The results demonstrate that C/NC events occur most frequently on straight and level road segments with no controlled intersections or traffic control devices when drivers are performing secondary tasks. Thus, the reasons for these crashes are carelessness and overconfidence. In addition, a median strip or barrier and a wider road can significantly reduce the frequency and severity of crash events. Moreover, gender, age, average annual mileage, and secondary tasks are highly correlated with the frequency and severity of C/NC events. Drivers with visual-spatial disabilities or crash records are more likely to be involved in the most severe crash events. Near-crash events occur more frequently at higher traffic density and on roads with traffic control devices and controlled intersections. These conditions may keep drivers alert, preventing crashes.

The cost of the wider impacts of road traffic on local communities: 1.6% of Great Britain's GDP

This paper estimates the negative effects of motorised road traffic on the travel and walking behaviour of local residents in Great Britain and the cost of the wider negative impacts on local economic activity, external effects of motorised transport, social exclusion, neighbourhood social capital, self-rated health, and subjective wellbeing. We use the results of a survey (n = 3038) and models linking the characteristics of roads and pedestrian crossing facilities in each participant’s local area, travel and walking behaviour, and the level and monetary value of the wider impacts of travel behaviour. The costs of road traffic borne by local communities were estimated as £31.9 billion per year, i.e. 1.6% of the Gross Domestic Product, or £631 per person. This value varies within the interval £569-£698/person/year, depending on the assumptions made. The highest estimated costs of motorised road traffic are reduced neighbourhood social capital (£236) and reduced subjective wellbeing (£196/person/year). The costs for some population segments, such as London residents, city residents, and people aged 25–34 are higher than the average. The characteristic of roads causing the highest costs is volume of motorised traffic above low (£264/person/year), followed by multiple lanes (£148), traffic speeds above low (£119), and absence of a median strip (£60). By quantifying for the first time, at the national level, the costs of the negative community effects of motor vehicles, this study provides evidence supporting policies to reduce traffic volumes and speeds and reallocate roadspace to pedestrians.

Impact of Different Combinations of Green Infrastructure Elements on Traffic-Related Pollutant Concentrations in Urban Areas

Urban air quality is a major problem for human health and green infrastructure (GI) is one of the potential mitigation measures used. However, the optimum GI design is still unclear. The purpose of this study is to provide some recommendation that could help in the design of the GI (mainly, the selection of locations and characteristics of trees and hedgerows). Aerodynamic and deposition effects of each vegetation element of different GI scenarios are investigated. Computational fluid dynamics (CFD) simulations of a wide set of GI scenarios in an idealized three-dimensional urban environment are performed. In conclusion, it was found that trees in the middle of the avenue (median strip) reduce street ventilation, and traffic-related pollutant concentrations increase, in particular for streets parallel to the wind. Trees in the sidewalks act as a barrier for pollutants emitted outside, specifically for a 45° wind direction. Regarding hedgerows, the most important effect on air quality is deposition and the effects of green walls and green roofs are limited to their proximity to the building surfaces.

Features of Methods for Assessing the Long-Term Traffic Intensity in the Design of Toll Roads

Long-term traffic intensity is among core characteristics that determine main parameters while developing projects for construction of new highways. The long-term traffic intensity influences estimated speed, pavement design, total number of traffic lanes, width of traffic lanes and roadsides, longitudinal slope, radii of horizontal curve, transverse slope, radii of convex and concave curves regarding the longitudinal profile, width of median strip, layout of intersection or junction with other roads.Existing methods for predicting traffic intensity for toll roads are also deterministic and cannot estimate the range of values for the listed indicators. In this regard, the objective of the study is to identify the features, advantages, and disadvantages of existing methods for assessing the long-term traffic intensity for toll roads.The study considered both traditional, classical methods (extrapolation, historical analysis, approximation) and promising innovative approaches based on the theory of fuzzy logic and neural network modelling.