Theory Of Urban Systems Research Articles

Urban water system theory and its model development and application

Urban water system theory and its model development and application

Placing Urban Renewal in the Context of the Resilience Adaptive Cycle

Resilience thinking provides valuable insights into the dynamics of complex adaptive systems. To achieve resilience in urban systems, it can be fruitful to delve into the intricacies of resilience processes. This paper theorizes about how the specific characteristics of resilient systems can be integrated into the spatial design of cities. Emphasizing the importance of the built form and spatial systems in maintaining order within urban processes, we focus on how adaptive renewal cycles can be applied to various systems and dimensions where urban change, adaptation, and renewal occur. The paper identifies key resilient system characteristics applicable to urban spatial form and contextualizes urban renewal within the adaptive renewal cycle—a framework originally developed to capture temporal and spatial ecosystem dynamics. We integrate insights within ‘space syntax theory’, theorizing about how cities renew themselves over space and time. We discuss instances of ‘compressed resilience’ and the challenges posed by the ‘tyranny of small decisions’ in urban planning and development. In conclusion, we identify future research directions in the theory of spatial morphology and resilient urban systems, emphasizing the need for a deeper understanding of the interplay between urban processes, urban form, resilience, and adaptive renewal.

Bringing together urban systems and food systems theory and research is overdue: understanding the relationships between food and nutrition infrastructures along a continuum of contested and hybrid access

Urban dwellers’ food and nutritional wellbeing are both dependent on infrastructure and can be indicative of wider wellbeing in urban contexts and societal health. This paper focuses on the multiple relationships that exist between food and infrastructure to provide a thorough theoretical and empirical grounding to urgent work on urban food security and nutrition in the context of rapid urban and nutrition transitions in the South. We argue that urban systems and food systems thinking have not been well aligned, but that such alignment is not only timely and overdue but also fruitful for both thematic areas of research and policy. We draw in particular on work within wider urban political economy and political ecology that can be classified as part of the ‘infrastructural turn’ that is influential with urban studies but little acknowledged within food studies. Drawing on these literatures helps us to better understand the interrelationships between people, things and ideas that make up both infrastructure and food systems. Policy, planning and research relating to both food and urban systems cannot afford to ignore such interlinkages, though much policy still operates on the neat assumptions of progressive connectivity to ‘the grid’ and formal food retail. Instead we argue how in many urban governance systems, a variety of hybrid mechanisms—on and off the grid, public and private formal and informal—better represent how urban residents, particularly the most marginalised, meet their everyday food and infrastructural needs along a continuum of gridded and off-grid access.

Recognition of digital twin city from the perspective of complex system theory: Lessons from Chinese practice

Urban system theory seeks to comprehensively capture the complexity of cities. Digital twin cities are “digital mirror images” or symbionts of physical cities, and thus, they form a complex adaptive system. Unlike the reductionist practice of urban informatization and digitalization, digital twins are expected to enable human beings to enjoy the complex beauty of the city for the first time, capable to perceive more information of city and deal with more complex urban problems. Some practical misunderstandings have emerged, however, as a result of simple technical stacking, which is not able to solve urban problems from the root of the problem; has biased thinking about digital twin cities, which treats them as technical tools; and has slowed development of digital twin innovative applications. To solve these problems, we need to draw on basic urban theory. On the basis of complex system theory, in this study, we comprehensively analyzed the characteristics and mechanisms of digital twin cities and constructed a system framework for digital twin cities. We further elucidated the digital twin city and deconstructed it from the perspective of system theory into four subsystems: the planning system, infrastructure system, industrial system, and public service facility system. We then analyzed the subsystem rules and changes in the digital twin city, as well as the principles and development trends that conform to the self-organization and self-adaptive laws of the city.

Spatiotemporal Evolution and Cause Analysis of Urban Housing Investment Resilience: An Empirical Study of 35 Large and Medium-Sized Cities in China

In this study, we explore the evolution and formation mechanism of urban housing investment resilience from three perspectives: theoretical analysis, model construction, and empirical testing. Based on the three-element theory of investment decision making and urban resilience system theory, a theoretical framework of urban housing investment resilience is constructed. Spatiotemporal analysis and qualitative comparison methods are used to divide 35 large and medium-sized cities into two categories, first-tier and non-first-tier cities, and their spatiotemporal characteristics and differences in terms of formation mechanism differences then explored. The results show that (1) the overall housing investment resilience of the 35 investigated cities is low, with the characteristics of periodic evolution, and there are obvious differences between the first-tier and non-first-tier cities as well as unbalanced development problems. (2) The three internal investment decision factors of returns, costs, and expectations and the five external support factors of economic growth, infrastructure development, labor market, policy regulation, and monetary policy do not, by themselves, constitute the necessary conditions for high levels of urban housing investment resilience, and there are three paths for the development of high levels of housing investment resilience in both first-tier and non-first-tier cities. (3) The twos types of cities have the same conformational path of "return- and cost-driven" but different dedicated conformational paths, including "cost-driven", "expectation- driven", and "return- and expectation-driven", and the core conditions in their driving paths are different, with real estate policy being the core condition in the path of first-tier cities and infrastructure development and labor markets being the core conditions in the path of non-first-tier cities. (4) There is a potential substitution relationship between the three configuration paths of first-tier and non-first-tier cities, and the substitution relationship between the two types of cities is also different. The findings of this study reveal that the complex interaction between the urban resilience system, represented by infrastructure construction, and multiple factors, including the three elements of investment, can have an impact on the resilience of real estate investment.

Застосування статистичних методів наукових досліджень при обстеженні пасажиропотоків міського автомобільного транспорту

The purpose of the paper is to propose scientific and methodological approaches to the generalization of passenger flow survey methods, the formation of the route transport network of the city, the calculation of the required type and number of rolling stock of passenger road transport, the formation of a list of preferential routes. The paper examines applied aspects of the application of the theory of urban passenger transportation in relation to transportation by means of passenger road transport of the city (PRTC). The main concepts of the theory of urban passenger transport and the issue of interaction between urban passenger transport and the city being served are analyzed on the basis of system concepts. An analysis of the main factors that affect the quality of planning, control and regulation of passenger road transport in the transport systems of cities has been carried out. Aspects of the theory of urban transport systems and design calculations of passenger transport by road are also considered. The research was carried out by the formation of new scientific and methodological approaches and scientific argumentation proposed on the basis of numerous works of domestic and foreign scientists in the field of passenger transportation organization. Research method are mathematical statistics and modeling. The solution to the tasks of urban transport service is divided into two main complexes: the design of urban transport systems, and the organization of urban transport traffic. To form an optimal or rational route network, as well as to effectively use rolling stock and ensure a high level of passenger service, it is necessary to know the directions, sizes and degree of unevenness of passenger flows, the specific values of which are established during certain surveys. When surveying passenger flows, it is necessary to obtain reliable data in order to use them in solving problems of improving the quality of passenger service. But when choosing a survey method, it is necessary to take into account the complexity of the method and the costs of its implementation.

Empowering Urban Governance through Urban Science: Multi-Scale Dynamics of Urban Systems Worldwide

Cities are facing many sustainability issues in the context of the current global interdependency characterized by an economic uncertainty coupled to climate changes, which challenge their local policies aiming to better conciliate reasonable growth with livable urban environment. The urban dynamic models developed by the so-called “urban science” can provide a useful foundation for more sustainable urban policies. It implies that their proposals have been validated by correct observations of the diversity of situations in the world. However, international comparisons of the evolution of cities often produce unclear results because national territorial frameworks are not always in strict correspondence with the dynamics of urban systems. We propose to provide various compositions of systems of cities in order to better take into account the dynamic networking of cities that go beyond regional and national territorial boundaries. Different models conceived for explaining city size and urban growth distributions enable the establishing of a correspondence between urban trajectories when observed at the level of cities and systems of cities. We test the validity and representativeness of several dynamic models of complex urban systems and their variations across regions of the world, at the macroscopic scale of systems of cities. The originality of the approach resides in the way it considers spatial interaction and evolutionary path dependence as major features in the general behavior of urban entities. The models studied include diverse and complementary processes, such as economic exchanges, diffusion of innovations, and physical network flows. Complex systems dynamics is in principle unpredictable, but contextualizing it regarding demographic, income, and resource components may help in minimizing the forecasting errors. We use, among others, a new unique source correlating population and built-up footprint at world scale: the Global Human Settlement built-up areas (GHS-BU). Following the methodology and results already obtained in the European GeoDiverCity project, including USA, Europe, and BRICS countries, we complete them with this new dataset at world scale and different models. This research helps in further empirical testing of the hypotheses of the evolutionary theory of urban systems and partially revising them. We also suggest research directions towards the coupling of these models into a multi-scale model of urban growth.

THE ALGORITHMS OF CONSTRUCTION OF INFORMATION SYSTEMS IN THE CONDITIONS OF SUBUBRANIZATION DEVELOPMENT

The article is devoted to the pressing issue of information support of territorial development processes. In the modern world, processes of information support of operational processes are of great relevance. Information and analytical support is the basis for making effective management decisions. In systems of urban development, urban and territorial development, the information component aims at ensuring the realization of three factors of development: economy, ecology and social development. In the conditions of sustainable development of society all three directions are balanced. However, due to certain imbalances in the system, humanity is searching for new forms of providing a comfortable life, work and leisure. Suburbanization has become one of these forms. Suburbanization is a trend of modern development of cities and territories in developed countries, which have high rates of socio-economic security. Suburbanisation is the process of centering the flow of people from large centers of economic gravity to the suburban area, which has the best environmental performance, which is possible in the case of ensuring the social component of human life. The relevance of suburbanization processes has necessitated the need for research on information and analytical support for these processes. In particular, the basic elements of the model of the structure of the urban planning system were identified and the dual connections of information support of decision-making for the development of urban planning systems were analyzed. On the basis of this analysis the task of information support of town-planning systems was determined. Based on the analysis of problems of special theory of urban planning information systems, it is proposed to develop an algorithm for information and analytical support of urban planning systems in the context of suburbanization processes. It has been determined that the automation of information support processes for urban planning systems management in today's digital society is the basis for the formation of effective urban development activities. In a three-prong urban development model that integrates issues of economy, ecology and social protection, suburbanization issues play a crucial role. The processing, analysis and evaluation of information on the development of town-planning systems make it possible to determine the leading trends and tendencies of development, as well as to predict the design of processes of town-planning activity. Keywords: urban planning, management of urban planning systems, suburbanization, information systems

Spatial Heterogeneity in the Determinants of Urban Form: An Analysis of Chinese Cities with a GWR Approach

It is of great significance to investigate the determinants of urban form for shaping sustainable urban form. Previous studies generally assumed the determinants of urban form did not vary across spatial units, without taking spatial heterogeneity into account. In order to advance the theoretical understanding of the determinants of urban form, this study attempted to examine the spatial heterogeneity in the determinants of urban form for 289 Chinese prefecture-level cities using a geographically weighted regression (GWR) method. The results revealed the spatially varying relationship between urban form and its underlying factors. Population growth was found to promote urban expansion in most Chinese cities, and decrease urban compactness in part of the Chinese cities. Cities with larger administrative areas were more likely to have dispersed urban form. Industrialization was demonstrated to have no impact on urban expansion in cities located in the eastern coastal region of China, which constitutes the country’s most developed regions. Local financial revenue was found to accelerate urban expansion and increase urban shape irregularity in many Chines cities. It was found that fixed investment exerted a bidirectional impact on urban expansion. In addition, urban road networks and public transit were also identified as the determinants of urban form for some cities, which supported the complex urban systems (CUS) theory. The policy implications emerging from this study lies in shaping sustainable urban form for China’s decision makers and urban planners.

Governança colaborativa e regimes urbanos: convergências inesperadas em tempos difíceis

Resumo O presente artigo busca estabelecer uma linha teórica-metodológica que, ao mesmo tempo, separe e articule os elementos constituintes da chamada teoria dos regimes urbanos e do conceito de governança colaborativa. Partimos do pressuposto de que as transformações contemporâneas vivenciadas pelas cidades (maior concorrência por investimentos privados, ênfase no planejamento estratégico, mercantilização dos espaços públicos, entre outros) podem ser melhor compreendidas a partir da análise dos processos decisórios sobre as políticas urbanas, com maior presença dos negócios urbanos na política pública. Tal tarefa exige abrir um debate com a comunidade acadêmica no sentido de superar os problemas de “nacionalização” dos modelos conceituais. Para tanto, apresentamos breves considerações sobre os regimes urbanos, a governança colaborativa e as implicações teóricas envolvendo democracia e mercado.

Comparación multinivel de grandes sistemas urbanos

For the first time the systems of cities in seven countries or regions among the largest in the world (China, India, Brazil, Europe, the Former Soviet Union (FSU), the United States and South Africa) are made comparable through the building of spatio-temporal standardised statistical databases. We first explain the concept of a generic evolutionary urban unit (“city”) and its necessary adaptations to the information provided by each national statistical system. Second, the hierarchical structure and the urban growth process are compared at macro-scale for the seven countries with reference to Zipf’s and Gibrat’s model: in agreement with an evolutionary theory of urban systems, large similarities shape the hierarchical structure and growth processes in BRICS countries as well as in Europe and United States, despite their positions at different stages in the urban transition that explain some structural peculiarities. Third, the individual trajectories of some 10,000 cities are mapped at micro-scale following a cluster analysis of their evolution over the last fifty years. A few common principles extracted from the evolutionary theory of urban systems can explain the diversity of these trajectories, including a specific pattern in their geographical repartition in the Chinese case. We conclude that the observations at macro-level when summarized as stylised facts can help in designing simulation models of urban systems whereas the urban trajectories identified at micro-level are consistent enough for constituting the basis of plausible future population projections. Keywords: urban system, Zipf's law, Gibrat, cities trajectories, BRICS

An Overall Urban System: Integrating Central Place Theory and Urban Network Idea in the Greater Pearl River Delta of China

Following a half century of popularity, central place theory experienced 20 years of neglect when the new urban system theory of network modeling gained attention at the beginning of the 1990s. However, central place theory remains valid, and it seems there has been a reemergence with it. Using the Greater Pearl River Delta (Greater PRD) as an experimental study region, this paper intends to present an empirical study that validates central place theory and shows that it can be integrated into an overall regional urban system. The study uses the compound Central Place Importance (CPI) to evaluate whether there is a hierarchy among the urban centers within the study area. The results indicate the existence of a hierarchy. Furthermore, empirical observation finds distinct complementarity relationships, rank-size distributions, and co-operative actions between the different cities, thus substantiating the claim that central place theory can be incorporated into an overall regional urban system. Besides, the presence of the densely distributed modern infrastructure system also appears to constitute a dimension of the overall urban system. There need further theoretical and empirical studies in order to support this proposition.

Multilevel comparison of large urban systems

For the first time the systems of cities in seven countries or regions among the largest in the world (China, India, Brazil, Europe, the Former Soviet Union (FSU), the United States and South Africa) are made comparable through the building of spatio-temporal standardised statistical databases. We first explain the concept of a generic evolutionary urban unit ("city") and its necessary adaptations to the information provided by each national statistical system. Second, the hierarchical structure and the urban growth process are compared at macro-scale for the seven countries with reference to Zipf's and Gibrat's model: in agreement with an evolutionary theory of urban systems, large similarities shape the hierarchical structure and growth processes in BRICS countries as well as in Europe and United States, despite their positions at different stages in the urban transition that explain some structural peculiarities. Third, the individual trajectories of some 10,000 cities are mapped at micro-scale following a cluster analysis of their evolution over the last fifty years. A few common principles extracted from the evolutionary theory of urban systems can explain the diversity of these trajectories, including a specific pattern in their geographical repartition in the Chinese case. We conclude that the observations at macro-level when summarized as stylised facts can help in designing simulation models of urban systems whereas the urban trajectories identified at micro-level are consistent enough for constituting the basis of plausible future population projections.

Toward an integrated theory of spatial morphology and resilient urban systems

We take the first step in the development of a new field of research with the aim of merging spatial morphology and resilience science. This involves a revisiting and reunderstanding of the meaning of sustainable urban form. We briefly describe the fields of resilience science and spatial morphology. Drawing on a selected set of propositions in both fields, we put urban form in the context of the adaptive renewal cycle, a dynamic framework model used in resilience science to capture the dynamics of complex adaptive systems, of which urban systems are prime examples. We discuss the insights generated in this endeavor, dealing with some key morphological aspects in relation to four key attributes of resilience, i.e., “change,” “diversity,” “self-organization,” and “learning.” We discuss and relate these to urban form and other social variables, with special attention paid to the “backloop phase” of the adaptive renewal cycle. We conclude by postulating ways in which resilience thinking could contribute to the development of a new research frontier for addressing designs for resilient urban social-ecological systems, and end by proposing three strategic areas of research in such a field.

Voice, Exit, and the Development of Urban Hierarchy: Evidence from Early Modern Europe

Recent research has emphasized the role of historical institutions in explaining variation in contemporary development. However, empirical research in this vein has assumed a geographically homogenous treatment of national institutions on sub national regions. Drawing on both contemporary and historical theory of urban systems, this paper argues there is in fact reason to believe that the effect of national institutions is likely to vary across space within a country. Specifically, the effect of de jure national representative institutions is likely to vary based on a region’s distance from its government or capital city. However, theory suggests that the direction of the effect of distance is ambiguous, as distance can lead to worse de facto institutions and thus growth by undermining the regions ‘voice’, or improve de facto institutions by facilitation ‘exit’. Heterogeneity in the effect of national representative institutions are tested on panel data set of European cities for the period 1500-1800. The results indicate that autocratic institutions were likely to have had a stronger negative association with city growth for those cities close to their polity’s capital in the early part of this period, but the direction of this association had reversed by the eve of the industrial revolution. This temporal heterogeneity may have been due to changes in transportation costs, and thus state capacity over this period.

PRODUCT DIFFERENTIATION, SKILL DISTRIBUTION, AND SYSTEMS OF CITIES IN A NORTH‐SOUTH TRADE MODEL

The objective of this paper is to investigate the impact of free trade on the structure of urban systems, skill distribution, income disparities, and welfare. The paper proposes a model that integrates international trade theory and the theory of urban systems. This is done in a two/three sector, spatial, general equilibrium model of a North‐South trade. Each country is populated with a continuum of unskilled workers with heterogeneous potential ability. Workers can acquire skill by investing in training. Thus, skill distribution in both countries is determined endogenously in the model through self‐selection. The economy produces a final good with the use of differentiated intermediate inputs and unskilled workers. The differentiated inputs are produced by skilled workers. Cities are formed in this model as a result of investment in public infrastructures and knowledge spillover among diverse skilled workers. I characterize two different types of spatial equilibria: a closed‐economy equilibrium, in which each country consists of a system of cities without trade, and a free‐trade equilibrium, in which we allow for trade between cities and countries. One of the main findings of the model is that free trade induces further productivity due to the agglomeration of diverse skilled workers. Thus, the model demonstrates a channel through which international trade interacts with the agglomeration economy through urban labor markets. Furthermore, free trade affects the structure of cities within the system.

Accounting for the 'Subnational Penn Effect' — A General Theory of Regional and National Price Levels

We develop a general theory of regional (inter-city) price dispersion which also explains the “subnational Penn effect”, i.e. cross-city correlations among population size, prices, real income and human capital stock. As a version of the neoclassical urban systems theory (Henderson, 1974), our model features a trade-off between agglomeration economies in production and urban congestion costs associated with increased land and service prices that brings forth differentiated cities. We explain the circular mechanism that translates a high land price to high local service prices. The model is also a theory of international price dispersion that is observationally equivalent to and more appealing than the Balassa-Samuelson theory, with the implication that the (international) Penn effect may simply be an aggregate result of the “subnational Penn effect”. Furthermore, it shows that, contrary to the popular view, economic integration can increase as well as decrease spatial price variation.

An evolutionary theory for interpreting urban scaling laws

We try here to illustrate the relevance of an evolutionary theory of urban systems for explaining their hierarchical properties. The largest cities became larger because they were successful in adopting many successive innovations. Larger cities capture innovations in a continuous way (through adaptation, imitation, anticipation), and they concentrate a larger part of anything « new » at any time. Their functions demonstrate a higher level of complexity or sophistication of their urban activity and society. The most advanced technologies concentrate in largest cities, the common place activities are ubiquitous, whereas old ones remain in small towns only (or, in economic terms, there are increasing, constant or decreasing returns to urban scale). Such regularities can be expressed in the form of scaling laws that were recognised as revealing specific constraints on the structure and evolution of complex systems in physics and biology. Approaching urban activities by scaling laws provides a linkage between the concepts of urban function, city size, and innovation cycles. Over time, there is a substitution among the activities of the largest cities, where the oldest technologies and professions are replaced by the new ones, while the old ones are relatively concentrating in the smallest towns. Such an evolution is observed within urban systems where cities are fully connected and interdependent. There are processes of cooperation through exchanges of information and learning that enable an incremental diffusion of innovation and a continuous adaptation of urban activities and society in all parts of the system. Meanwhile, there are also processes of competition between cities that enhance their capacity to innovate and to levy the benefits of innovation. A distributed process of urban growth including a slight but continuing advantage for the largest cities is the result of that competitive process, while the successive adaptation of the urban functions follows the economic and social innovation cycles.

Looking for Sustainable Urban Mobility through Bayesian Networks

There is no formalised theory of sustainable urban mobility systems. Observed patterns of urban mobility are often considered unsustainable. But we don’t know what a city with sustainable mobility should look like. It is nevertheless increasingly apparent that the urban mobility system plays an important role in the achievement of the city’s wider sustainability objectives.In this paper we explore the characteristics of sustainable urban mobility systems through the technique of Bayesian networks. At the frontier between multivariate statistics and artificial intelligence, Bayesian networks provide powerful models of causal knowledge in an uncertain context. Using data on urban structure, transportation offer, mobility demand, resource consumption and environmental externalities from seventy-five world cities, we developed a systemic model of the city-transportation-environment interaction in the form of a Bayesian network. The network could then be used to infer the features of the city with sustainable mobility.The Bayesian model indicates that the city with sustainable mobility is most probably a dense city with highly efficient transit and multimodal mobility. It produces high levels of accessibility without relying on a fast road network. The achievement of sustainability objectives for urban mobility is probably compatible with all socioeconomic contexts.By measuring the distance of world cities from the inferred sustainability profile, we finally derive a geography of sustainability for mobility systems. The cities closest to the sustainability profile are in Central Europe as well as in affluent countries of the Far East. Car-dependent American cities are the farthest from the desired sustainability profile.

Structure and Dynamics in an Urban Landscape: Toward a Multiscale View

Ecosystems and city systems often form hierarchically structured landscapes whose spatial pattern is scale dependent. While trends in the upper tail of national city-size distributions leave the impression that fractal-scaling laws such as Zipf’s law or the rank-size rule truly represent the essence of the system, the linearity depicted at aggregate scale actually obscures variation and discontinuity in the urban size-density function, including multimodalities evident in regional data sets. Tracing individual city trajectories through these hierarchical patterns reveals structural resilience at macroscopic scale, the punctuated growth of individual cities of differing sizes, the persistence and self-reinforcing character of spatial agglomeration, and a general need for further empirical investigation of the relationship between city size and growth. It also raises questions for future exploration, including the meaning of persistent departures from the power laws of traditional urban systems theory. Interpretation of such departures in the context of questions of jurisdictional scale in environmental management and “smart growth” policy adds a practical dimension to the research agenda.