Quantitative analysis of the road network in the city of Constantine

The road network of the city of Kryvyi Rih is an example of the adaptation of the street and road network to their historical and economic development. The city was formed as a result of the historical unification of the territories of individual mining villages and microdistricts that arose around the mines, which were located along narrow (up to several kilometers) iron ore strips stretching from north to south for more than 100 km. In fact, the modern elongated linear structure of the city is the result of this historical process, which is considered a key factor in almost all aspects of its development and primarily influenced the development of motor highways. Thus, the main transport highways of the city of Kryvyi Rih stretch from north to south, which significantly increases the distances between districts and creates a significant load on the main transport arteries. The purpose of the study is to conduct a geospatial analysis of the road network of the city of Kryvyi Rih in order to improve its functionality. The work is based on geodata on the city's street and road network, which were obtained from the crowdsourced platform Open Street Map in Shape file format. Geospatial analysis of the city's road network was performed using the open source QGIS program. The city actually consists of several separate districts, interconnected by highways of various types - from wide main streets of city and district significance, which provide connections within the settlement, to residential streets and driveways, the main purpose of which is access to buildings and structures. In addition, important main roads connecting different regions of Ukraine pass through the city. Geospatial analysis of the Kryvyi Rih highway network has shown that different types of city highways differ in their structure. Thus, main roads form a radial scheme, which is characterized by a network of roads in the form of radial lines, which diverge in the form of rays from three centers. Main streets of city and district significance form a combined scheme and are a combination of several structures. It is based on a radial structure, which is unloaded by means of highways in the form of rectangular and linear structures. The rectangular structure of the city street and road network dominates in the organization of motor transport traffic on residential streets, especially newly built microdistricts of the residential area. For thoroughfares, a free structure scheme with a disordered street and road network is characteristic. The density of the road network within the city varies unevenly. The largest number of roads is observed along two conditional axes (vertical and horizontal), each of which divides the city, respectively, into two parts. These "hot" zones actually provide the majority of intra-city and transit passenger and freight traffic. The basis of these zones are highways and main roads, which carry the main load of motor vehicle traffic. Residential and through roads provide the interconnection between main roads and their connection with the territories of residential areas. In Kryvyi Rih, road crossings and junctions are carried out mainly at the same level, at the expense of intersections. The city's road network includes almost 26 thousand intersections, which corresponds to a density of 60 intersections per km². It should be noted its significant spatial correlation with the road density indicator: the largest number of intersections is along the transport axis connecting the north and south of the city. The general street and road network differs from the network of highways and main streets of city and district significance by an abnormally high number of intersections in the historical center of the city. There are two "hot" zones, which correspond mainly to intersections formed by residential and through roads. The influence of natural and anthropogenic relief on the city's road network is limited mainly to determining the directions of highways and main roads. The development of the road network of the city of Kryvyi Rih lags behind its real needs; today the network is unable to simultaneously and effectively pass the number of vehicles that are in the city. The uneven development of the road network and its topology on the territory of the city has been revealed, which often does not correspond to the dynamic capabilities and directions of the predominant movement of intra-city and transit transport. The lack of a sufficient number of alternative routes for connecting highway and main road nodes characterizes the network as one that has a low level of redundancy. This primarily concerns the movement of transit transport, most of which moves through the central areas of the city. Keywords: geospatial monitoring; geographic information systems; network structure; road density; intersection density; network efficiency; digital terrain model; relief slope map.

The article presents the stages of forming a model of a multimodal transport network of an urban passenger transport port of a million-plus city. A method for determining the location of an optimal multimodal transport interchange hub on the city's road network is proposed. The analysis of the change in the population of Volgograd was carried out, the location of the proposed multimodal transport hubs was determined by the administrative districts of the city. A multimodal model is constructed, which is a flat graph with vertices in multimodal transport hubs and transport links, characterized by distances along the city's street and road network.

The problems of traffic management in large cities are complicated as the increase in traffic volume far exceeds the road network capacity. It leads to saturation of the road network, which negatively affects its functioning. This article analyzes the state of the art of improving the quality of road traffic by predicting the size of traffic after the implementation of traffic management measures. While the issue of modeling traffic flow parameters based on technological factors has been sufficiently studied, the problems of considering the human factor need to be clarified. The object of study is traffic flow on the city's road network. The criteria used by drivers to compare the characteristics of alternative traffic routes were identified based on the field study results. Based on the data obtained, the parameters of alternative routes that drivers choose when driving on the road network are formed. According to the survey results, the most significant factor is the minimum mileage along the route. Deviations from the shortest route were determined to determine the patterns of distribution of correspondence of non-route vehicles along alternative routes. It made it possible to define the distribution of transport correspondence along alternative routes. Since the process under consideration is probabilistic, the law of distribution of a random variable was determined. After having determined the law of distribution of a random variable for the data obtained, the calculations showed that the change in the random variable is well described by the gamma distribution. It was determined that the share of transport correspondence that will be carried on them decreases as the length of the route deviates from the shortest one. The obtained results make it possible to predict road network congestion by modeling the distribution of traffic flows. In further research, it would be advisable to analyze the distribution of transport correspondence by other criteria.

During the transformation of city road network, with the change of the local road network capacity and the section nature, the road capacity is affected, travel time is changed, the traveler's route choice behavior changes too. The travel time characteristics under different conditions are discussed based on the basic travel behavior characteristics research during the city road network reconstruction. Mining the state and The relationship between the reliability of travel time, traveler route choice behavior and road network capacity is studied. The research has values on traffic control and management, especially when city road is being rebuild. With the size and population expanding of city, large cities becoming more and more congestion, road network needs to be optimized. How to maintain traffic flow smoothly is a big problem during the road network reconstruction. In order to maintain traffic flow smoothly during the road network reconstruction, the travelers' psychology and action need to know clearly when they were not under normal traffic conditions and their traffic choice behavior will affect the local road network operation even in a whole. So it is very necessary to discuss road network capacity, travelers path selection behavior, and relationship between travel time and the other parameters. And traveler behavior regularity should be studied too to keep road network effective. 1. The Traveler Behavior Characteristics in Road Network Rebuilding During city road network transformation period, the local even the whole network operation is affected. Travelers' psychology subject to certain interference, their travel behavior appear difference from the normal state. These characters are as follows: (1) The traffic flow's spatial-temporal heterogeneity: in network transformation period, local sections or interval exists the problem of traffic congestion, cause traveler abnormal travel psychology and behavior. This will easily cause the adjacent traffic flow suddenly scattered and suddenly collected, and the situation is obvious space-time inhomogeneity. (2)The short-term change of traveler psychology: during network transformation, some road sections can be limited for travel, causing local road network interruption, this make traveler's psychology changed. The travelers will optimize their road selections based on individual cognition and intelligent transportation system. (3) The expected shortest travel time in psychology: travel space and time

French motorways: experience and assessment

Racism, discriminatory practices, institutional bias, and systematic exclusion can take lasting physical form in the built environment. There has been growing attention to the long-term consequences of housing policies and practices on social and economic outcomes, including residential segregation, but comparatively less attention to other aspects of the built environment, such as road networks and spatial (dis)connectivity. In this article, we introduce a novel method that constructs counterfactual road networks by identifying missing road segments that we would expect to exist in a city's road network, given the surrounding infrastructure. We demonstrate the empirical application of the method by analyzing differences in racial composition and residential segregation for the observed and counterfactual road networks of five U.S. cities. We find that unexpected disconnectivity in a city's road network is associated with greater differences in the racial composition of nearby areas and higher levels of segregation at the local and city level. Our findings suggest that road networks warrant more attention as a factor that may contribute to the persistence of segregation.

National and provincial road networks have a major role to provide high accessibility and mobility to all community. Their services both functional and structural, therefore, need to improve continuously. Current figures show that from 2002 to 2003 the length of the road networks increased 8.07%. During these years, it was found that the road investment increased 28.61% and AADT increased 8.80%. However, it was not followed by the road networks performance, such as the IRI increased 39.5%, the road networks with SDI>50 increased 84.01%, and the road network in bad condition increased 64.92%. The purpose of this paper is to highlight and review technical aspects of the road networks performance particularly their quality standard achievement. Finally this paper discusses reasons of decreased quality performance of the road networks whilst increased investment and maintenance cost occurred. Keyword: technical review, pavement quality, IRI, SDI, investment, national and provincial road Permalink: http://www.ejournal.undip.ac.id/index.php/mkts/article/view/3902 [How to cite: Mulyono, A.T. dan Riyanto, B., 2005, Telaah Teknis terhadap Kinerja Mutu Perkerasan Jalan Nasional dan Propinsi, Jurnal Media Komunikasi Teknik Sipil , Volume 13, Nomor 1, pp. 108-118]

Robustness of city road networks at different granularities

The actual state and quality of road transport operations largely depend on the efficiency of city transport on the road network. The economic development of cities, the level of comfort and living conditions of people in the settlements of the country hinge on the quality indicators of its operation. Since the level of efficiency of the city's road network heavily depends on the effectiveness of points of maximum concentration of traffic – transport and planning nodes, special attention should be paid specifically to these elements of the city's road network. In this regard, the analysis and research of energy consumption of the traffic flow as one of the criteria for assessing the choice of engineering solutions for transport and planning nodes is an actual direction for further scientific research. At the same time, the optimization of their planning decisions is considered only as one of the components in the system approach to minimizing the transport energy costs both in the road network of cities and in the transport sector of Ukraine as a whole. This paper considers the energy estimation as one of the criteria for justifying the choice of the engineering solution for the intersection of city highways by the example of a transport and planning hub at the intersection of the Kiltseva Doroga – Prospekt Peremohy – Prospekt Academika Palladina in Kyiv. To carry out the relevant assessment, a model is used to estimate the impact of energy consumption of the transport stream on the rationale for choosing an engineering and planning solution for intersecting city highways, taking into account the influence of individual design parameters characterizing the choice of their planning decisions, as compared to the model for determining the transport energy consumption with the help of the simulation tool, PTV Vissim software application.

Structural robustness of city road networks based on community

Traffic management has been a hot topic in recent years. However, how to model a city road network as well as the objects on road network still faces some problems. Previous data models for city road network typically focus on two types of objects, which are the city road network and the moving objects in the road network, and neglect the static spatial objects in road network. This will degrade the performance of spatiotemporal queries in city road network, especially that of nearest neighbor queries (NN queries) or K-NN queries. In this paper, based on a study on the characteristics of city road network and moving objects, we propose a new moving objects data model which can effectively represent city road network and the moving objects in it. The new model improves previous models with the introduction of static spatial objects. The detailed definition of the city road network as well as the moving objects and static objects are discussed. Compared with previous models, our new model is more effective to represent spatiotemporal queries over city road network.

Rural road networks, together with national and provincial road networks constitute a complete road network system. It is widely distributed, covering most parts of the rural areas. Road network layout is a core part of the road network planning system; its rationality and feasibility directly impact the success of road network planning. Based on the characteristics and research of rural road network layout, a method combines FCM (Fuzzy C-Means) clustering algorithm and traffic location method. The validity of the method is tested through an application example.

This paper instantly infers the gas consumption and pollution emission of vehicles traveling on a city's road network in a current time slot, using GPS trajectories from a sample of vehicles (e.g., taxicabs). The knowledge can be used to suggest cost-efficient driving routes as well as identifying road segments where gas has been wasted significantly. The instant estimation of the emissions from vehicles can enable pollution alerts and help diagnose the root cause of air pollution in the long run. In our method, we first compute the travel speed of each road segment using the GPS trajectories received recently. As many road segments are not traversed by trajectories (i.e., data sparsity), we propose a Travel Speed Estimation (TSE) model based on a context-aware matrix factorization approach. TSE leverages features learned from other data sources, e.g., map data and historical trajectories, to deal with the data sparsity problem. We then propose a Traffic Volume Inference (TVI) model to infer the number of vehicles passing each road segment per minute. TVI is an unsupervised Bayesian Network that incorporates multiple factors, such as travel speed, weather conditions and geographical features of a road. Given the travel speed and traffic volume of a road segment, gas consumption and emissions can be calculated based on existing environmental theories. We evaluate our method based on extensive experiments using GPS trajectories generated by over 32,000 taxis in Beijing over a period of two months. The results demonstrate the advantages of our method over baselines, validating the contribution of its components and finding interesting discoveries for the benefit of society.

Urban road efficiency is one of the most important facets of transport planning that holds huge implications for traffic flow rates, travel times, and overall mobility in urban areas. This study focuses on the influence of bi-directional traffic flow on urban road efficiency and takes Norwalk, CT as a case study. Arising from this, a holistic dataset with different traffic variables, such as average speed, vehicle delays, and free-flow factors was used to analyze the performance of bi-directional zones of the city's road network. From the analysis, bi-directional traffic zones have very varying efficiency levels, with average speeds ranging from 4 mph to 43 mph and very different vehicle delays. The median travel speed for these areas averaged 18 mph, which suggests moderate congestion. The average daily traffic volume was vastly different: some barely had any traffic, while others were as high as over 26,000 vehicles per day. The study also found that some of the variables used, like zone length and traffic volume, played a very important role in determining road efficiency; in most cases, longer zones and higher volumes increased delays and lowered speeds. Comparative and correlation analyses prove that, compared to the non-bi-directional zones, bi-directional zones generally sustain higher vehicle hours of delay. That is, as much as the bi-directional flow would accommodate traffic from both directions, under specific conditions, it contributes to congestion. Therefore, from the results, it follows that target-oriented traffic management strategies is required to optimize road efficiency in bi-directional zones, more so within an urban setup with constraints in space and infrastructure. The study concludes with several major recommendations to urban planners and traffic engineers for the adoption of context-specific solutions to making the road more efficient in bi-directional zones.

The article focuses on a detailed analysis of the legislative and regulatory framework and theoretical sources of domestic and foreign experts on the problem of making urban planning decisions on the organization of greening of the street and road network of urban settlements. The main functions of greening - urban planning and ecological - are singled out and characterized. A study of the street and road network of Kyiv was carried out with a decomposition of problem areas related to urban improvement and landscaping, namely: an inefficient surface drainage system, increased soil salinity along the roadway and pedestrian zones, a limited life span of tree and shrub plantings. The foreign experience of greening city streets was studied, where the main attention is paid to the restoration of biodiversity due to the sowing of onion grasses with a ban on mowing, planting trees and shrubs for nitrogen fixation and soil retention from landslides, erosion, significant wind load, preservation of soil moisture due to the use of various types of mulching for the vital activity of beneficial microorganisms and provision of water-soluble plant nutrients, arrangement of rain gardens and ditches, where moisture can accumulate after significant atmospheric precipitation and directly feed the plants that grow nearby, and already the excess rainwater is subject to extraction in the surface drainage network. A principle model of the stages of selection of green spaces for the street and road network of cities is presented according to the following aspects: urban planning conditions and restrictions, agrotechnical and decorative properties of green spaces, performance of ecological and urban planning functions by green spaces. When organizing landscaping, the importance of taking into account the needs of different users of public spaces (drivers and passengers of vehicles, cyclists and pedestrians), as well as the nature and function of adjacent buildings, is emphasized. The range of problems of the organization of greening of urban transport hubs and races of the city of Kyiv has been determined. The importance of developing uniform standards for the organization of greening of the street and road network of cities, criteria and indicators of the quality of greening, taking into account the functions and principles of greening organization, is emphasized. The development of the specified quality indicators will make it possible to approach the choice of plant assortment on city streets and roads in a balanced and rational manner, and the implementation of such urban projects will meet the requirements of time and the ecological state of urban settlements.