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This study contains an assessment of air pollution levels in Trafalgar Road, Greenwich. This is a congested road on a main route into central London, which has achieved notoriety since its residents took legal action in an attempt to restrict traffic. The four types of dispersion model used in the assessment are briefly described. All four models show that there is a likelihood that air quality standards for a number of pollutants, particularly PM₁₀, will be exceeded in the vicinity of busy congested roads in London. Zones where standards are exceeded are restricted to regions within 10m or so from the road. Any assessment has to take account of concentrations on a very fine scale (at distances of 10m from a road).

Purpose – This chapter reviews the provision for freight transport in Shanghai, and makes recommendations for the development of road freight including the aspects of optimizing the port transportation system, strengthening the planning and construction of freight terminals, promoting the formation of a city distribution system, adjusting downtown traffic policies, and promoting the provision of road freight information systems.

Methodology – Based on primary data and observation, this chapter describes the status of road freight in Shanghai and details existing problems. Based on experience elsewhere it then proposes changes in policy.

Findings – This chapter proposes some recommendations as follows: optimizing the collection and distribution system of the Shanghai port, planning, and construction of road freight terminals, adjusting the freight traffic policy in the central area and improving the performance of freight firms.

Implications – These recommendations, based on good practice elsewhere, should both enhance the efficiency of road freight in Shanghai and reduce its environmental impacts.

Value of chapter – The study will help the sound and orderly development of Shanghai's road freight transportation, better satisfy the needs of the people, and promote the development of Shanghai economy.

The purpose of this paper is to attempt to put forth an innovative geographic information system (GIS)‐based methodology for demarcating stretches of mountain roads with differential probability of road accidents. The proposed methodology has been tested in a sample road network of Uttarkashi district in Uttaranchal (India) and exhibits potential of reducing the frequency of road accidents by adopting suitable site‐specific measures along accident‐prone stretches.

The paper is based on the hypothesis that road accidents in the mountain roads are largely due to the three basic road parameters that distinguish mountain roads from those in the plains; sinuosity, gradient, and width. The sinuosity of the road is calculated for every 500 meter stretch of the road map layer while for delineating the gradient of the road topographic data of Survey of India maps have been used. The paper utilises GIS‐based environment for correlating these parameters and delineating accident‐prone road stretches.

The proposed new methodology for delineating differential accident risk in mountain roads has been utilised for demarcating road stretches with differential probability of road accidents and the output has been correlated with the actual road accident database of Uttarkashi district in Uttaranchal. The correlation exhibits the potential of this methodology for practical mitigative planning‐related purposes. The same can also be utilised for better aligning the planned roads.

Human factor is the most important determinant of road accidents and non‐incorporation of this parameter is the biggest limitation of the proposed methodology. Further, the effectiveness of the proposed methodology is the function of the validity of the hypothesis. The methodology is, however, highly flexible and has ample scope for accommodating other parameters as well. The effectiveness of the output is, however, a function of the accuracy of the input maps. Road layer considered in this paper has been prepared from the maps available with the State Government Department (Public Works Department) and their alignment does not depict the ground details. Input road layer prepared with precision Geographical Positioning System (GPS), preferably differential, mapping would produce more realistic results. The positions of the past accident sites for the purpose of correlations are taken from the data provided by the State Police Department and these are not very accurately determined. GPS‐based database of the accident locations would help in effective correlations.

The methodology proposed in this paper is an attempt to scientifically delineate differential accident‐prone stretches of the mountain roads. This would pave the way for implementation of site‐specific measures for reducing probability of road accidents and better aligning of the proposed roads.

Previously a large number of workers have used GIS‐based techniques for delineating hazard and risk related largely to landslides, floods and earthquakes but the same has never been employed for delineating road accident risk. The methodology is simple, unique, original and functional and has immense practical utility for reducing the menace of road accidents in mountain roads.

To establish a stimulating traffic model of ring road systems and study the traffic effects of ring road in the center of a large city, including the influence in vehicle's travel time and distance.

Different from the ring road systems in the west, Beijing and other big cities in China build ring roads in city center. However, it seems that those systems do not work because the traffic problem still exists when the number of cars in the city increased quickly in past five years. According to the real geographic topology network structure around Er Huan road in Beijing city center, a simplified simulated traffic model was built. Then, two indices of traffic effects, average travel time and path length were studied by comparing the two models with or without ring road.

According to the simulation, although a high‐speed ring road shortens the travel time, it isolates the nature road network system and increases travel distance in the city center. Furthermore, it is uneconomic building a ring road to relieve traffic jams.

Only Er Huan road in Beijing traffic system was simulated in the model. A more complicated ring road system needs to be developed.

A useful model for optimizing traffic system with ring roads, and providing a support for doubting the strategy of developing ring road in city center district in many cities of China.

This is a new way by establishing the simulation model to analyze the scheme of ring road traffic systems. Furthermore, advice for current situation are concluded and it is useful for optimizing current traffic system.

The quantitative assessment of environmental effects should be carried out using the indicators that ensure the best objectivity and efficiency of the environmental impact assessment (EIA) process. The aim of this paper is to clarify the effectiveness of the methods used for prognoses of air pollution from roads. The benchmark method proposed in this paper is based on theoretical knowledge and on analysis of data collected from EIA reports.

The paper includes a literature review and developing of the benchmark method. This research was based on data dispersion analysis, determination of benchmarks, usage of regression method, as well as confrontation of different methods of determination of air emission concentration used in EIA.

The simplified model has been designed for determination of concentration of dust emission in the air from motor roads, the building or reconstruction of which is planned. The results indicate that the benchmark method for determination of air pollution with particulate matter PM10 has been elaborated, which can be used for environmental impact evaluation in motor road construction. The method has been elaborated relying on measurement data of existing motor roads and displays a high level of probability of credibility.

The method is simpler and less time‐consuming than the currently used calculation model. It produces a more precise result than the calculation model. It is outstanding and important since the further development of motor road projects can undoubtedly be judged by the results of EIA.

The results of this research provide a rational and comparative approach for finding the methods of determination of the air emission concentration used in EIA in producing the credible outcome. The results reported in the research show existing problems with calculation of emissions from roads. The proposed benchmark method is simple, easy to use and credible.

The purpose of this paper is to present a model to determine which roads to be built in each stage with limited budget.

A multistage network discrete expansion model with budget restriction is formulated and a heuristic algorithm is developed by the technique of comparing the original shortest paths and the sum of crossed shortest paths to avoid computing the shortest paths matrix repeatedly.

The optimal approach has a very significant effect in finding which roads to be built by the largest net benefit.

The paper discusses a new multistage network discrete expansion problem is the main research implications.

The optimal choice for road building schedule of new urban district when budgets were limited.

The paper presents a model and an algorithm for the optimization of road building schedule based on budget restriction.

The purpose of this paper is to introduce a weighted average method to process speed measurements from multiple magnetic sensors, which are installed on road segments. Speeds are weighted‐averaged in a fix duration time (5 minutes) for each sensor across location index of the sensor where it was installed. The proposed method is evaluated with numeric and simulation results.

Unlike traditional vehicle average speed measurements, the authors propose a weighted‐average speed measurement method of road segment, using wireless magnetic sensor nodes, which are installed on the measured road segment. Magnetic sensors offer a non‐contact vehicle detection method, and small sensors with relatively low power consumption. Using magnetic sensors, the local changes in the Earth's magnetic field caused by the presence of a moving vehicle can be measured and the vehicle's speed obtained. Next, using adaptive weighted average algorithm and space weighted algorithm in a fixed period, the weighted average travel speed of road segment can be obtained.

In current literature, there are many methods to measure vehicles' speed on road, such as image‐based, radar‐based, GPS‐based, double‐loop‐based or magnetic sensor‐based, but most of them only provide individual vehicle speed. Using probe vehicles, mean travel speed of road segment can be obtained, but it is costly on hardware and measurement, because many probe‐vehicles need to be used on roads and many measurements need to be done everyday. GPS data can be used to provide valuable travel speed data for Intelligent Transportation System (ITS). However, not every vehicle is equipped with GPS and to access ID numbers for personal cars would entail privacy problems. Mean travel speed of road segment is obtained based on statistical average speed. Generally, statistical average speed is used, which is based upon Gaussian distribution is not true in traffic systems.

By using wireless magnetic sensor nodes, vehicle instantaneous speeds are obtained in a fixed time when vehicles are passing over sensor nodes and then the adaptive weighted average speed on each sensor node location is computed based on the monitoring data from each sensor node in the fixed time. Considering different weights of each lane and road space (in the middle of the road segment or near the intersection), the proposed scheme can obtain the weighted‐average speed of the road segment.

The purpose of this study was to investigate the likely causes of failure of some sections of road pavements in Ajaokuta, Northcentral Nigeria. This was achieved through a geotechnical assessment of subgrade soils in affected areas.

The methods entailed field and laboratory methods and statistical analysis. Subgrade soil samples were retrieved from a depth of 1,000 mm beneath the failed portions using a hang auger. The soils were analyzed for natural moisture content (NMC), Atterberg limit (liquid limit, plastic limit and linear shrinkage), grain size distribution, compaction and California bearing ratio (CBR), respectively.

The results of the geotechnical tests ranged from NMC (12.5%–19.4%), sand (84%–98%), fines (2%–16%), LL (16.0%–32.2%), PL (17%–27.5%), LS (2.7%–6.4%), PI (2.5%–18.4%), maximum dry density (1756 kg/m2–1961 kg/m2), optimum moisture content (13.2%–20.2%), unsoaked CBR (15.5%–30.5%) and soaked CBR (8%–22%), respectively. Pearson’s correlation coefficient performed on the variables showed that some parameters exhibited a strong positive correlation with r2 > 0.5.

Funding was the main limitation.

Comparing the results with Nigerian standards for road construction, and the AASHTO classification scheme, the subgrade soils are competent and possess excellent to good properties. The soils also exhibited very low plasticity, a high percentage of sand, high CBR and low NMC, which implies that it has the strength required for road pavement subgrades. The likely causes of the failures are, therefore, due to the use of poor construction materials, technical incompetence and poor compaction of sub-base materials, respectively.

The China’s Belt and Road Initiative (BRI, hereafter) has reenergized the Silk Road concept, with most literature focusing on the political and economic effects of the BRI. While certain aspects of the Digital Silk Road (DSR), digital component of BRI, have been researched, much less focus has been placed on the technological development, tech transfer and information diffusion aspects of the BRI. The aim of this study is to investigate the opportunities, issues and critiques that have arisen as a result of the Belt and Road Initiative’s implications on innovation, knowledge transfer and dissemination.

Research in its nature is descriptive. Literature reviews are a significant part of the development of a field. Therefore, secondary sources were considered.

The literature and the study have highlighted several opportunities, problems and criticism that decision-makers and the relevant agencies and institutions should take into account when deciding how to move forward with BRI and its digital component DSR.

This paper contributes to the research literature on BRI and its subset DSR’s impacts on innovation, knowledge transfer and information diffusion. In fact, the DSR’s primary aim is to strengthen international cooperation in the digital economy. Furthermore, digital platforms now play a significant role in global trade, emphasizing the necessity of DSR.