Urban Network System Research Articles

Exploring the role of configurational accessibility of alleyways on facilitating wayfinding transportation within the organic street network systems

Despite the significant role of alleyways in urban spatial configuration and accessibility as critical structures of urban infrastructure, there remains a noticeable gap in understanding their specific role in urban transportation policies. The main aim of the present study is to investigate the role of configurational accessibility of alleyways in facilitating wayfinding within organic street network systems. A mixed method was applied using Space Syntax and empirical observations. Moreover, Pearson correlations and t-tests were used to discern the association between variables and compare independent groups using SPSS software. The findings from the syntactical analysis strongly indicate that alleyways significantly impact configurational accessibility within urban network systems. Furthermore, the complex and labyrinthine structure of organic alleyways was found to significantly hinder the intelligibility of urban areas, making navigation more challenging. The results revealed a significant correlation between vehicle mobility and connectivity values, with higher levels of mobility consistently linked to increased connectivity values. The outcomes also indicated that alleys connected to main streets play a crucial role in facilitating wayfinding within urban network systems. This study contributes to a more profound understanding of the role of alleyways in urban network systems for urban planners and transportation engineers, paving the way for more targeted sustainable urban planning strategies.

The Structural and Functional Development of an Urban Network System from the Perspective of Flow Space: A Case Study of Nanjing

Abstract: Globalization and informatization have exerted far-reaching impacts on the spatial connection and development of urban systems. This study, concerning the network of an urban system based on the space of flows, supplements the insufficiency on the micro-level in macro-urban network research. Taking Nanjing as an example, this study explores the characteristics of the network of the urban system from the perspective of people flow, refining the granularity of the analysis to the township- and street-level spatial units using mobile phone data. The findings are as follows: (1) There is a multicenter layered network pattern, with the main urban area being the core of the network, while Dongshan Street and Moling Street, as secondary centers, form a joint development pattern with the main urban area. (2) The spatial differentiation is significant. The spatial heterogeneity of “centralization in the central region, delayering in the north, and hierarchization in the south” is obvious. The net people inflow nodes are mainly concentrated in the main urban area and its surroundings, while the net outflow nodes are mostly located on the edge of the city. Moreover, the nodes to the south of Yangtze River are advantageous in urban resource control. (3) The phenomenon of “double shadow circle” appears in the ring of the main city and the ring of the municipal area. Moreover, the northern district experiences a serious outflow of population. (4) The effect of policy intervention is beginning to show. Improved levels of development of street and township units such as Jiangbei New District show the positive influence of national strategy on regional development.

Does Urban Agglomeration Promote the Development of Cities? Evidence from the Urban Network Externalities

This paper discusses whether urban agglomeration can promote urban growth from the perspective of network externalities. Although agglomeration externalities play an important role in promoting regional development, improved accessibility makes urban network externalities an influential force in reshaping regional economic growth. This paper identifies the urban network based on the data of train frequency and travel time data among 271 cities in China. Then, the spatial Durbin model is used to investigate the effect of urban agglomeration on economic growth from the perspective of urban network externalities. The results demonstrate that there are significant network externalities among cities in China, which play a pivotal role in boosting urban growth. Interactions among cities produce cross-regional spillovers, causing network externalities to no longer be dependent on geographical proximity. This is significantly different from agglomeration externalities that are limited to a certain regional scale. As the scope of the urban network expands, network externalities become more pronounced. Different regional characteristics all lead to heterogeneous results of network externalities. The construction of high-speed railways, as well as the well-developed urban network system, strengthen the positive impact of network externalities. Smaller cities benefit more from higher-level urban networks than regional networks.

Monitoring House Vacancy Dynamics in The Pearl River Delta Region: A Method Based on NPP-VIIRS Night-Time Light Remote Sensing Images

Urban spatial interaction integrates cities into closely related urban network systems in continuous urban regions. However, it also brings differentiation and has mutual negative impacts between each location. Unbalanced development is one such impacts and needs closely monitoring. The housing vacancy rate (HVR) in a continuous urban region is an important index in the unbalanced development of a continuous urban region since it indicates the uneven distribution of population and investment across cities. This study uses NPP-VIIRS NTL data and Landsat 8 OLT images to estimate HVRs at the district level. Additionally, this study tracks the spatial–temporal dynamics of HVR distributions in the Pearl River Delta (PRD) region. The comparison between the sampled HVRs and estimated HVRs verifies the effectiveness of the estimated HVRs in identifying dynamic changes in HVRs. This study has found that although overall decreasing HVRs are observed in the PRD, speculations and irrational real estate investment exist in cities on the west bank of the Pearl River Estuary and in some isolated districts in other cities. Furthermore, increasing proportions of vacant pixels in most cities indicate rising real estate development, requiring further supervision. This study suggests that more precise data and advanced techniques could help to improve the accuracy of the estimation techniques.

A study on the evolution of economic patterns and urban network system in Guangdong-Hong Kong-Macao greater bay area.

The COVID-19 pandemic has seriously affected China's macroeconomy, industrial transformation, and high-quality development. Research on economic patterns and urban network systems can provide a reference for healthy development of the regional economic system. The evolution of the economic pattern and urban network system of Guangdong-Hong Kong-Macao Greater Bay Area (GBA) from 2010 to 2020 is investigated using methods (e.g., the gravity center model, the gravitational force model, social network analysis, and geographic information system). (1) The gravity center of gross domestic product (GDP) of the GBA is located in Nansha district, Guangzhou, with a skewing direction northwest-east-northwest and a movement rate of "large-small-large." The center of import and export and the center of consumption show a "zigzagging migration" in which the center of investment shows an "irregular (random) migration". (2) The economic connection degree of cities in the GBA exhibits a high ascending velocity, and the whole area tends to be mature, with a significant effect of spatial proximity. With the steady increase in network density, there is significant polarization of network centrality in the region. The four major cohesive subgroups have been relatively stable and consistent with the degree of geographic proximity of the cities. The center-periphery structure is more significant, in which the core area is extended to the cities on the east coast of the Pearl River Estuary, thus forming the core cluster of "Hong Kong-Shenzhen-Guangzhou-Dongguan." In this study, the evolution of economic patterns and urban network systems in the GBA over the past decade is analyzed using multiple methods (i.e., gravity model, urban network system analysis, and geographic information system) based on urban socioeconomic data by starting from various spatial elements (e.g., "points, lines, and networks") to gain insights into and optimize research on regional economic development after the COVID-19 pandemic.

Resilience Assessment of Multimodal Urban Transport Networks

With the development of urbanization and the evolution of urban network systems, multimodal urban transport network (MUTN) systems play a vital role in improving network effects and operational efficiency. However, urban transport networks are easily affected by natural disasters and traffic incidents, which can lead to significant human and economic losses. Accordingly, it is vital to be able to assess the resilience of transport networks in the face of various disruptions. This study, therefore, utilizes complex network theory to analyze the resilience of multimodal urban transport networks, with the resilience accessed based on topological indices. The MUTN in Beijing is selected as a case study for simulation analysis. Based on the road network and subway network, a model MUTN is established, and the Monte Carlo method is used to simulate random attacks. The results show that the MUTN in Beijing has good resilience against disruptions. This study guides the evaluation of the overall resilience of multimodal urban transport networks and will be useful for transportation planners and decision-makers in dealing with emergencies and natural disasters in the future.

Coupling characteristics of coastal ports and urban network systems based on flow space theory: Empirical evidence from China

The port–city coupling system and spatial correlation are new perspectives in studying the port–city relationship. The flow space and the element network activate the economic location through the temporal and spatial compression effect, reshape the temporal and spatial relationship, and challenge the traditional port–city relationship. Based on the theory of ‘flow space’ and the ‘port–city relationship’, this study constructs two network systems of port and city. A theoretical framework and a measurement method for evaluating the coupling relationship between the port-city and the city from the perspective of flow space are proposed. Using Chinese coastal port cities as examples, this paper discusses the network characteristics and coupling patterns of port–city relations in the context of port regionalisation. The main findings are as follows. First, the port network system is subject to obvious geographical constraints and exhibits the network characteristics of ‘group development’ and ‘axis-spoke’ coexistence; the urban network system reduces to a certain extent the dependence on the space of port cities. It shapes the traditional geographical space and exhibits the network characteristics of ‘multi-core’. Second, types of port–city coupling are diverse, but the regional agglomeration characteristics are obvious. Compared to 2006, the distribution of coupling types in the whole network system of port cities in 2016 is relatively balanced, and the structure tends to be perfect. Finally, flow elements and port functions are the core elements that influence the coupling characteristics of port cities from the perspective of ‘flow space’. The flow element promotes an advanced community relationship between port cities. The port and the city realise the greatest value and the highest comprehensive efficiency. Due to the intergenerational differences of ports, the impact of port functions on the evolution of city functions is different, leading to some level differences in the development of port cities.

Analysis on the Status Quo and Construction Problems of Domestic Urban Civil Air Defense Engineering System in China

As the urbanization process in developing countries continues to accelerate, although my country has achieved significant results in planning and construction, there are still many problems. For example, the rate of urban green space decreases with the continuous increase of urban buildings. Therefore, the domestic urban underground civil air defence Engineering construction is in a very important position at this stage, and our development goals must be shifted from above ground to underground. This article analyzes the general situation of the domestic civil air defence engineering system, expounds on the current situation and existing problems of my country's urban civil air defence engineering system, which has an important influence on the development of my country's cities. Functional departments must take into account the various functions of civil air defence projects and put people's safety first. At the same time, firefighters should also improve their professionalism, leadership and organizational skills, and evacuate people when encountering danger and arrange for them to take refuge in designated locations. The technicians in the relevant departments in the city need to use scientific and technological means to mix the urban network system in series and parallel so that the various structures of the urban network system are unified and interact with each other. When a disaster strikes, it can protect the safety of the people and reduce the economic loss of the city. Reduce to the lowest level to maximize benefits.

The use of traffic data from automatic monitoring systems to obtain day-to-day time series of vehicle traffic volumes and origin-destination flows in urban networks

The understanding of travel pattern dynamics in the urban environment is essential for the transportation systems planning and operation. Recently, the increasing availability of massive traffic data from traffic monitoring systems, including automatic number plate recognition systems (TMS-ANPR), can allow an understanding of the day-to-day variability of traffic flows in large urban network systems. However, to enhance the data quality for analysis, it is essential to carry out a previous data treatment. This work presents a method for treatment of TMS-ANPR data. The main product of this data treatment are the day-to-day time series of traffic volumes and OD flows for different periods of a typical day, allowing the analysis of the multiday dynamic of travel behavior and of the model assumptions stated in the literature about such dynamic behavior. The proposed method, which can be applied to any type of TMS-ANPR, was applied to generate time series data from the TMS-ANPR of Fortaleza city, contributing to identify suspicious and atypical data, to define representative patterns of vehicular traffic and to estimate series of OD flows.

Hospital performance in a large urban acute myocardial infarction emergency care system: Tokyo Cardiovascular Care Unit network

Background: An ideal urban network system for improving regional acute myocardial infarction (AMI) outcomes should be geographically balanced and uniform according to regional population in performance of participating hospitals. The objective of our study is to evaluate whether there is a major difference in risk-adjusted in-hospital mortality between the Tokyo Cardiovascular Care Unit (CCU) network hospitals, which cover the whole population of large cities.Methods: The study subjects were all AMI patients without cardiac arrest on arrival admitted to the Tokyo CCU network hospitals from 2009 to 2017. Risk-adjusted in-hospital mortality rates (RAMRs) were compared between the categories of each hospital-level factor. A hospital-level multivariable linear regression was modeled to analyze the association between RAMRs and hospital-level factors. A funnel plot was constructed by plotting RAMRs against hospital volumes.Results: From 2009 to 2017, there were 42,123 hospitalizations for AMI in Tokyo CCU network hospitals (n=72, as of December, 2017). There were no significant differences in RAMRs in the comparison of hospital backgrounds. Each hospital background was not significantly associated with the RAMR. Considering the 99% CI in funnel plots, only five hospitals (7.2%) were located outside the control limits.Conclusions: There was no major difference in the RAMRs between the participating hospitals within the Tokyo CCU network, despite the different hospital backgrounds.

Distributed urban network systems in the tropical archaeological record: Toward a model for urban sustainability in the era of climate change

Identifying and employing the concept of sustainability in the social sciences remain a challenge. One approach presented here emphasizes its utility in examining past urban adaptations primarily from the archaeological record that demonstrate the role of low-density urbanism. Drawing upon early semitropical cities and their dispersed land-use and settlement patterns, both longevity and interconnectivity are shown to have developed in the context of environmental and societal diversity. The impact of climate change to our near-term futures can result in adaptations that accommodate positive societal transformations if all relevant disciplines are included in the dialogue. Past sustainable practices when melded with thoughtfully deployed technologies of today and tomorrow will assist with this new ecology. We argue that generating knowledge about tropical urban systems in the ancient past adds to a more diversified pool of urban models from which to draw for future urban planning. We specifically suggest that networked urban systems of distributed, low-density settlement repeatedly occurring throughout the tropical archaeological records have several social–environmental benefits toward a sustainability transition of cities in the era of climate change.

Research on World City Evaluation System Based on the Concept of Regional Space “Flow”

In 2012, the United Nations published the white paper “Big Data for Development: Challenges and Opportunities”, pointing out that the “big data era” has arrived. The concept of “data stream” will continue to profoundly affect all aspects of the global economy, society and life. The “vertical” relationship between cities in the traditional urban hierarchy is gradually replaced by the “horizontal” relationship in the urban network system. As the concept of “big data” gradually moves from theory to practice, the world city evaluation system is based on the evidence of air passenger flow, port logistics, Internet information flow data, enterprise top 100 multinational corporations’ enterprise layout and scale data, and high-end productive service industry. Data research, further reorienting the path of urban competitive advantage from the perspective of world urban network, proposes the strategy of urban competitiveness improvement under the background of the world urban network system, which undoubtedly promotes the refinement of China’s big data urban and rural planning to the planning process. Scientific advancement provides guarantee and technical support for scientific and rational planning results.

A Learning Automata Based Stable and Energy-Efficient Routing Algorithm for Discrete Energy Harvesting Mobile Wireless Sensor Network

Wireless sensor networks (WSN) have been widely used in urban network system and networked monitoring system, which provide easy connectivity and high physical data rate. Considering the battery-limited property of sensor nodes, recently, energy harvesting (EH) technology is introduced into WSN, which can alleviate traditional WSN problems (energy consumption, energy equilibrium, transmission efficiency, etc.). Current EH-WSN routing algorithms generally use the continuous energy harvesting mode, therefore, how to design an efficient routing algorithm for discrete energy harvesting mode and ensure the overall energy balance and conservation is still a great challenge and needs to be solved. Especially, under the mobile environment, the impact of route stability needs to be considered, which makes the design more complicated. To address the above problems, we propose a learning automata (LA) theory based stable and energy-efficient routing algorithm for discrete EH-mobile WSN (DEH-LA-SERA, for short). Firstly, we construct a multi-factors measurement model for sensor nodes, which contains node stability model, energy ratio function, expected harvesting energy model (using Markov decision process method) and direction judgement model. On this basis, we derive the node weighted value, i.e., selecting probability, which can be used to determine whether a node can be chosen as relay node. Secondly, with the help of LA theory, we construct a feedback mechanism to adjust the optimal path. With this solution, we can ensure the overall energy balance and conservation while holding the stability of selected path. As demonstrated in simulation experiments, our algorithm, DEH-LA-SERA, achieved the best performance in route survival time, energy consumption, energy balance and acceptable performance in end-to-end delay and packets delivery ratio.

Spatio-Temporal Pattern of the Urban System Network in the Huaihe River Basin Based on Entropy Theory.

As complex systems, the spatial structure of urban systems can be analyzed by entropy theory. This paper first calculates the interaction force between cities based on the gravity model, the spatial relationship matrix between cities is constructed using the method of network modeling, and the spatial network modeling of urban system can be calculated. Secondly, the Efficiency Entropy (EE), Quality Entropy (QE), and System Entropy (SE) of urban system network are calculated and analyzed by information entropy. Finally, taking the Huaihe River Basin (HRB) as a case study, model verification and empirical analysis are performed. It is found that the spatio–temporal pattern of the urban system network structure in the basin is uneven: in space, the urban system network in the HRB presents a layer-by-layer spatial distribution centered on the core city of Xuzhou; meanwhile, the overall urban system network in the basin presents an orderly development trend. This study has certain theoretical and practical value for the planning of urban and urban systems and the coordinated development of regions.

Bidirectional urban flows in rapidly urbanizing metropolitan areas and their macro and micro impacts on urban growth: A case study of the Yangtze River middle reaches megalopolis, China

Bidirectional urban flows of materials, technologies and information are becoming more frequent, and cities are closely connected socially, economically and technologically. Thus, an open, mobile and polycentric urban network has gradually formed. However, most of the recent studies on urban landscape dynamics regarded each city as a single entity and ignored intercity relatedness. In this study, we took as an example the Yangtze River middle reaches megalopolis (YRMRM), which is one of the rapidly urbanizing metropolitan areas in China. We pose two research questions: (1) Do intercity factors impact the expansion of urban land at a macro level? (2) Do intercity factors impact the spatial patterns of urban growth at a micro level? We used geospatial big data to measure urban relatedness and spatial interaction among city groups from a macro perspective. Then, a spatially explicit approach based on a data field model was adopted to quantify the micro urban spatial interaction inside each city. The pattern of spatial interaction and its impacts on urban growth were also analysed. The results showed that the three city sub-groups developed well, with Wuhan, Nanchang and Changsha being the dominant cores. However, the macro intercity relatedness in the YRMRM has not broken the shackles of the geographical boundaries of the provinces. A highly connected polycentric urban network system has not been formed to date. Our empirical results indicated that intercity factors were the main drivers of both macro and micro urban growth dynamics in the YRMRM from 2005 to 2015. This finding suggests that population and information flows had strong effects on the promotion of urbanization in the YRMRM during this period. Thus, we argued that urban bidirectional flows should be a vital consideration in future urban spatial planning and regional development strategies.

Modeling Urban Collaborative Growth Dynamics Using a Multiscale Simulation Model for the Wuhan Urban Agglomeration Area, China

Urban agglomeration has become the predominant form of urbanization in China. In this process, spatial interaction evidently played a significant role in promoting the collaborative development of these correlated cities. The traditional urban model’s focus on individual cities should be transformed to an urban system model. In this study, a multi-scale simulation model has been proposed to simulate the agglomeration development process of the Wuhan urban agglomeration area by embedding the multi-scale spatial interaction into the transition rule system of cellular automata (CA). A system dynamic model was used to predict the demand for new urban land at an aggregated urban agglomeration area scale. A data field approach was adopted to measuring the interaction of intercity at city scale. Neighborhood interaction was interpreted with a logistic regression method at the land parcel scale. Land use data from 1995, 2005, and 2015 were used to calibrate and evaluate the model. The simulation results show that there has been continuing urban growth in the Wuhan urban agglomeration area from 1995 to 2020. Although extension-sprawl was the predominant pattern of urban spatial expansion, the trend of extensive growth to intensive growth is clear during the entire period. The spatial interaction among these cities has been reinforced, which guided the collaborative development and formed the regional urban system network.

Urban function connectivity: Characterisation of functional urban streets with social media check-in data

Social media check-in data, one type of crowdsourcing open data about individual activity-related choices, provides a new perspective to sense people's spatial and temporal preference in urban places. In this paper, through the analysis of the interaction between these scored places on streets, we aim to advance our knowledge of network accessibility with social media check-ins to portray urban structure and related socioeconomic performance more explicitly. By conceptualising an interface graph to reflect the interplay between land-use points and the co-visual paths, we propose a novel framework to characterise the urban streets with land-use connectivity indices that are measured with a new type of place-function signature. A “3-Ds” model is introduced to package three principal dimensions of urban function network, including accessible density, accessible diversity and delivery efficiency, as one integrated index that works towards a comprehensive understanding of function connectivity from each street's midpoints to all reachable land-use points. Streets are further partitioned to the annotated function regions based on function connectivity in different types of active land-use. The results of preliminary studies in the city of Tianjin, China show that the proposed metrics can explicitly describe the inherent function structure and the regions' typology across scales. Compared with space syntax measurements at the same radius for describing the variation of empirically observed house price, the integrated metric can improve the predictability of statistic models sufficiently, and each specified index is confirmed to be statistically significant by controlling other factors. Overall, this research shows that the usage of ubiquitous big social media data can enrich the current description of the urban network system and enhance the predictability of network accessibility on socioeconomic performance.

An empirical study on Chinese city network pattern based on producer services

Globalization and informatization have accelerated city networking process over the world, which makes research on city network a hot topic in the fields of urban geography and economic geography. With Chinese economic structure adjustment and city economic growth, producer services have begun to play an increasingly important role in city-region networking. This paper employs the methodology of world city network to analyze and explain the spatial development characteristics of China’s urban network system based on the data of nationwide producer services enterprise network. The research result indicated that the distribution of producer services network has a positive effect on the development of Chinese city networks. City network connectivity is closely related to the significance of city in producer services development, and the former will gradually decline with the drop of the latter. Accordingly, the 64 cities can be divided into the national central cities, regional central cities, sub-regional central cities and local central cities in accordance with their position and role in the nationwide producer services network. It is concluded that high-grade cities with quality producer services dominate the pattern of Chinese city networks and there emerges three spatial agglomerations of producer services enterprises in Changjiang (Yangtze) River Delta, Zhujiang (Pearl) River Delta and Beijing-Tianjin-Tangshan Economical Region. Moreover, the distribution of different producer services industry varies from city to city, which also affects the characteristics of network development.

Trans-European transport networks influence on the regional development and urban systems: Serbian experience

The trans-European transport network has different effects at macro regional mezzo-regional and micro-regional level, and its effectiveness rises with the lower regional levels. Possible approaches to the trans-European transport network impact and effect survey and policy options have been pointed out. The importance of increased accessibility and mobility for regional expansion and for a more balanced and polycentric system of city networks has been underlined. Changes in the spatial organization utilization and structure of cities, as well as in social benefits and losses subsequent to impacts of trans-European transport corridor "X" section Belgrade-Nis have been analyzed. The new trans-European or major transport infrastructure does not per se create regional and urban system network development, although it can affect the conditions for the processes that create growth and development. The effects can be increased by co-ordination of measures of regional, spatial and urban policy, land use transport, environmental and other policies. The necessary measure is the introduction of spatial impact assessment as sartorial policy instrument for the large transport infrastructure plans and projects.

Uticaj transevropskih saobracajnih koridora na regionalni razvoj i aglomeracione sisteme - iskustva Evropskih zemalja

The trans-European transport network has different effects at inter-regional, macro-regional and mezzo-regional level, and its effectiveness rises at the lower regional levels. Possible approaches to the trans-European transport network impact and effect survey and policy options have been pointed out. In that respect the brief review of surveys, strategic framework and policies in the European Union has been given. The importance of increased accessibility and mobility for regional expansion and for a more balanced and polycentric system of city networks has been underlined. The question is how the new major transport infrastructure affects the development of functional complementarity between cities and regions. The new trans-European or major transport infrastructure does not per se create regional and urban system network development, although it can affect the conditions for the processes that create growth and development. The effects can be reinforced by co-ordination of measures of regional and urban policy, land use, transport and other policies. The necessary measure is the introduction of spatial impact assessment as an instrument for spatial assessment of large transport infrastructure projects.