Scaling and universality in urban economic diversification

Understanding cities is central to addressing major global challenges from climate change to economic resilience. Although increasingly perceived as fundamental socio-economic units, the detailed fabric of urban economic activities is only recently accessible to comprehensive analyses with the availability of large datasets. Here, we study abundances of business categories across US metropolitan statistical areas, and provide a framework for measuring the intrinsic diversity of economic activities that transcends scales of the classification scheme. A universal structure common to all cities is revealed, manifesting self-similarity in internal economic structure as well as aggregated metrics (GDP, patents, crime). We present a simple mathematical derivation of the universality, and provide a model, together with its economic implications of open-ended diversity created by urbanization, for understanding the observed empirical distribution. Given the universal distribution, scaling analyses for individual business categories enable us to determine their relative abundances as a function of city size. These results shed light on the processes of economic differentiation with scale, suggesting a general structure for the growth of national economies as integrated urban systems.     

Scaling of patenting with urban population size: evidence from global metropolitan areas

Larger agglomerations of individuals create a social environment can sustain a larger repertoire of intellectual capabilities, thereby facilitating the creation and recombination of ideas, and increasing the likelihood that interactions among individuals will occur through which new ideas are generated and shared. Relatedly, cities have long been the privileged setting for invention and innovation. These two phenomena are brought together in the superlinear scaling relationship whereby urban inventive output (measured through patenting) increases more than proportionally with increasing population size. We revisit the relationship between urban population size and patenting using data for a global set of metropolitan areas in the OECD and show, for the first time, that the superlinear scaling between patenting and population size observed for US metropolitan areas holds for urban areas across a variety of urban and economic systems. In fact the scaling relationships established for the US metropolitan system and for the global metropolitan system are remarkably similar.     

How the geometry of cities determines urban scaling laws

Urban scaling laws relate socio-economic, behavioural and physical variables to the population size of cities. They allow for a new paradigm of city planning and for an understanding of urban resilience and economics. The emergence of these power-law relations is still unclear. Improving our understanding of their origin will help us to better apply them in practical applications and further research their properties. In this work, we derive the basic exponents for spatially distributed variables from fundamental fractal geometric relations in cities. Sub-linear scaling arises as the ratio of the fractal dimension of the road network and of the distribution of the population embedded in three dimensions. Super-linear scaling emerges from human interactions that are constrained by the geometry of a city. We demonstrate the validity of the framework with data from 4750 European cities. We make several testable predictions, including the relation of average height of cities and population size, and the existence of a critical density above which growth changes from horizontal densification to three-dimensional growth.     

Strategic Project Management to Use the Grand Challenge Scholars Program to Address Urban Infrastructure

Throughout the world, infrastructure to support cities is critical to support sustainable and responsible economic development. This can include new infrastructure projects in the case of growing areas. It can also include the renewal and upgrading of existing infrastructure in areas that have been inhabited and already developed. Infrastructure includes roads, bridges and transportation systems; power grids and energy service; internet and telecommunications; and water and sewer services. This development can be part of a system of systems, in which government, industries, and universities can contribute knowledge, skills, and abilities. This paper will investigate the strategic project management taken by one university to provide an academic experience that will prepare engineering students to address several of the Grand Engineering Challenges of the 21st Century, as identified by the US National Academy of Engineering. The challenges relating to energy, water, information, and urban infrastructure can be approached using the functions of teaching, research, and service. By approaching the challenges strategically, resources of faculty time, student effort and laboratory facilities can be leveraged to achieve greater results. This case study will describe the efforts and results to date and identify opportunities for future growth.     

Chains of damages and failures in a metropolitan environment: some observations on the Kobe earthquake in 1995

The interaction and the couple effects that may occur as induced and indirect consequences of any triggering hazard in metropolitan areas is one of the most important problems to be tackled during disasters, as the Kobe earthquake in 1995 showed very clearly. The analysis of direct, secondary and indirect effects of the Kobe earthquake suggests to substitute the concept of chain of losses and failures to the simple couple hazardous event-damages which is currently used. Not only parameters related to physical weakness or strength of the built environment should be considered by scientists, experts and decision-makers. Organisational, social, and systemic factors are equally crucial to understand the magnified dimension of disasters at increasing levels of exposed systems vulnerability. Linking failures due to different kinds of vulnerability one to the other permits to reconstruct complete event scenarios, where social and organisational elements are not simply added to the 'hard' components of cities, but contribute to explain why failures and losses occurred and why it took so long to repair them. Lifeline damage assessment provides a good example to show how physical, organisational and systemic vulnerabilities are intimately connected one to the other. The point of view from which governance problems related to prevention and emergency preparedness will be looked at is that of an urban and regional planner. When planners look for design solutions suitable for a specific town or region, they must constantly bridge between hard technical matters and social and economical concerns. Furthermore, they are forced to consider in their projects spatial and geographic dimensions. Those two typical features of planners' approach to problem solving can be interesting for scholars in the field of risk assessment and mitigation research.     

Potential advantages in combining smart and green infrastructure over silo approaches for future cities

Cities are incorporating smart and green infrastructure components in their urban design policies, adapting existing and new infrastructure systems to integrate technological advances to mitigate extreme weather due to climate change. Research has illustrated that smart green infrastructure (SGI) provides not only climate change resilience but also many health and wellbeing benefits that improve the quality of life of citizens. With the growing demand for smart technology, a series of problems and challenges, including governance, privacy, and security, must be addressed. This paper explores the potential to transition from grey, green, or smart silos to work with nature-based solutions and smart technology to help change cities to achieve considerable environmental and socio-economic benefits. The concepts of grey, green, and smart infrastructure are presented, and the needs, benefits, and applications are investigated. Moreover, the advantages of using integrated smart, green nature-based solutions are discussed. A comprehensive literature review is undertaken with keyword searches, including journal papers, stakeholder and case study reports, and local authority action plans. The methodology adopts multimethod qualitative information review, including literature, case studies, expert interviews, and documentary analysis. Published data and information are analysed to capture the key concepts in implementing SGI systems, such as storm-water control, flood and coastal defense, urban waste management, transportation, recreation, and asset management. The paper investigates the elimination of silo approaches and the alleviation of the destructions caused by extreme weather events using these interdependent SGI systems supported by novel data-driven platforms to provide nature-based solutions to boost the health and wellbeing of the residents.     

What can cities do to increase resilience?

This paper examines climate change mitigation and adaptation from an insurance industry perspective, with particular reference to London and the USA. It illustrates how British insurers are increasingly shaping public policy and using new technology to manage the risks from climate change impacts and makes a plea for society to make more use of insurance expertise in future decision making. In particular, more dialogue is needed between architects, planners and insurers to adapt our buildings and cities for climate change impacts. The paper is an abbreviated and updated version of the paper presented by the author in Houston, Texas, in 2005.     

Four degrees and beyond: the potential for a global temperature increase of four degrees and its implications

The 1992 UN Framework Convention on Climate Change commits signatories to preventing 'dangerous anthropogenic interference with the climate system', leaving unspecified the level of global warming that is dangerous. In the late 1990s, a limit of 2°C global warming above preindustrial temperature was proposed as a 'guard rail' below which most of the dangerous climate impacts could be avoided. The 2009 Copenhagen Accord recognized the scientific view 'that the increase in global temperature should be below 2 degrees Celsius' despite growing views that this might be too high. At the same time, the continued rise in greenhouse gas emissions in the past decade and the delays in a comprehensive global emissions reduction agreement have made achieving this target extremely difficult, arguably impossible, raising the likelihood of global temperature rises of 3°C or 4°C within this century. Yet, there are few studies that assess the potential impacts and consequences of a warming of 4°C or greater in a systematic manner. Papers in this themed issue provide an initial picture of the challenges facing a world that warms by 4°C or more, and the difficulties ahead if warming is to be limited to 2°C with any reasonable certainty. Across many sectors--coastal cities, agriculture, water stress, ecosystems, migration--the impacts and adaptation challenges at 4°C will be larger than at 2°C. In some cases, such as farming in sub-Saharan Africa, a +4°C warming could result in the collapse of systems or require transformational adaptation out of systems, as we understand them today. The potential severity of impacts and the behavioural, institutional, societal and economic challenges involved in coping with these impacts argue for renewed efforts to reduce emissions, using all available mechanisms, to minimize the chances of high-end climate change. Yet at the same time, there is a need for accelerated and focused research that improves understanding of how the climate system might behave under a +4°C warming, what the impacts of such changes might be and how best to adapt to what would be unprecedented changes in the world we live in.     

每位中国建筑师为地震灾区做一次设计——全球再造都江堰

为了弥补本地设计力量的缺口，5.12大地震过后的半个月，成都市规划管理局在全世界范围内发出一封无偿设计邀请——都江堰市灾后重建规划概念方案征庥公告。     

Urban density,directed technological change,and carbon intensity: An empirical study based on Chinese cities

Technological change is one of the most effective methods to reduce carbon intensity. Meanwhile, cities are essential carriers of technological change and carbon emissions. Considering the extensive land expansion in urbanization which always manifests in the density of urban economic activity, this paper analyzes the relationship between urban density and carbon intensity and also the mediating role of directed technological change to explore the interaction among them. First, the authors construct a theoretical model that considers the knowledge production sector, final goods production sector, and technical choice. Second, based on the panel data of 280 cities in China from 2008 to 2017, the authors use the two-way fixed effect regression, mediation-effect regression, and panel-threshold model to examine the results. The results show that: (1) The increase in urban density helps to reduce carbon intensity. (2) Capital-saving technological change is a mediating factor in the path of urban density's effect on carbon intensity. (3) With the increase in market size, the effect of urban density on capital-saving technological change weakens, thereby weakening the inhibitory effect on carbon intensity. Findings can provide a reference for reducing carbon intensity in other countries to formulate reasonable and practical policies for sustainable urbanization, especially for developing countries.     

A sustainable city environment through child safety and mobility—A challenge based on ITS?

Our cities should be designed to accommodate everybody, including children. We will not move toward a more sustainable society unless we accept that children are people with transportation needs, and ‘bussing’ them around, or providing parental limousine services at all times, will not lead to sustainability. Rather, we will need to make our cities walkable for children, at least those above a certain age. Safety has two main aspects, traffic safety and personal safety (risk of assault). Besides being safe, children will also need an urban environment with reasonable mobility, where they themselves can reach destinations with reasonable effort; else they will still need to be driven. This paper presents the results of two expert questionnaires focusing on the potential safety and mobility benefits to child pedestrians of targeted types of intelligent transportation systems (ITS). Five different types of functional requests for children were identified based on previous work. The first expert questionnaire was structured to collect expert opinions on which ITS solutions or devices would be, and why, the most relevant ones to satisfy the five different functional requests of child pedestrians. Based on the first questionnaire, fifteen problem areas were defined. In the second questionnaire, the experts ranked the fifteen areas, and prioritized related ITS services, according to their potential for developing ITS services beneficial to children. Several ITS systems for improving pedestrian quality are discussed. ITS services can be used when a pedestrian route takes them to a dangerous street, dangerous crossing point or through a dangerous neighborhood. An improvement of safety and other qualities would lead to increased mobility and a more sustainable way of living. Children would learn how to live to support their own health and a sustainable city environment. But it will be up to national, regional and local governments, through their ministries and agencies and public works departments, to promote, fund, and possibly mandate such systems. It is clear that we need to offer an acceptable level of convenience, efficiency, comfort, safety and security to pedestrians but it is less clear if society will prioritize resources toward this.     

Failure analysis of historical buildings due to climate change

Historic buildings have a high resilience in time due to the fact that they were designed by taking into consideration the environment and all the local conditions. However, nowadays not only their environment is changing fast. According to a current climatic change analysis, the climate all over the world has already suffered a severe change and, unfortunately, future scenarios indicate an even worse situation. The main effects of the climate change are as follows: high and long lasting temperatures during summer, precipitation pattern change, intensification of the local winds. To which we can add more intense or even frequent extreme events, such as: drought, abundant precipitation, snowfalls and hailstorms. All these changes have a heavily impact not only on the historic buildings, but also on the economy and society. The main purpose of this study to analyse the climatic change on different types of historic buildings, the way in which natural factors increase the degradation and the failure of the building structures/historic architectural details and how it can affect the aesthetics of the historic urban centres. The subject of the research was a small town in Romania, Oravita, which was chosen due to its diversity of its historical heritage and its special climatic condition. The study focused on simple buildings as well as on archaeological sites, railroads, bridges and dams.     

COVID-19 policy analysis: labour structure dictates lockdown mobility behaviour

Countries and cities around the world have resorted to unprecedented mobility restrictions to combat COVID-19 transmission. Here we exploit a natural experiment whereby Colombian cities implemented varied lockdown policies based on ID number and gender to analyse the impact of these policies on urban mobility. Using mobile phone data, we find that the restrictiveness of cities’ mobility quotas (the share of residents allowed out daily according to policy advice) does not correlate with mobility reduction. Instead, we find that larger, wealthier cities with more formalized and complex industrial structure experienced greater reductions in mobility. Within cities, wealthier residents are more likely to reduce mobility, and commuters are especially more likely to stay at home when their work is located in wealthy or commercially/industrially formalized neighbourhoods. Hence, our results indicate that cities’ employment characteristics and work-from-home capabilities are the primary determinants of mobility reduction. This finding underscores the need for mitigations aimed at lower income/informal workers, and sheds light on critical dependencies between socio-economic classes in Latin American cities.     

Environmental assessment for non-prescribed infrastructure development projects: a case study in Bangkok Metropolitan

Rapid urbanization and urban growth have caused serious environmental problems in most cities of developing countries. Many infrastructure projects on varying scales have been implemented to meet the growing demands of such cities, but only a few are subjected to environmental impact assessment as part of the project approval process. In an attempt to justify environmental assessment (EA) for all infrastructure development projects (IDPs), irrespective of their scales, this paper investigates the environmental effects of large, medium and small IDPs implemented in urban fringe areas to understand and compare the nature of their impacts. The survey results show that respondents' perceptions of physical environment pertaining to air quality and noise were similar regardless of the scale of the project. However, in terms of vibration, surface water quality and ground water quality, the respondents' perceptions differed between large projects and small or medium projects. In order to avoid such negative impacts from IDPs in the future, this study proposes a mechanism for integrating EA into the planning and development control processes of local authorities.     

A Geodesign Method of Human-Energy-Water Interactive Systems for Urban Infrastructure Design: 10KM2 Near-Zero District Project in Shanghai

The grand challenges of climate change demand a new paradigm of urban design that takes the performance of urban systems into account, such as energy and water efficiency. Traditional urban design methods focus on the form-making process and lack performance dimensions. Geodesign is an emerging approach that emphasizes the links between systems thinking, digital technology, and geographic context. This paper presents the research results of the first phase of a larger research collaboration and proposes an extended geodesign method for a district-scale urban design to integrate systems of renewable energy production, energy consumption, and storm water management, as well as a measurement of human experiences in cities. The method incorporates geographic information system (GIS), parametric modeling techniques, and multidisciplinary design optimization (MDO) tools that enable collaborative design decision-making. The method is tested and refined in a test case with the objective of designing a near-zero-energy urban district. Our final method has three characteristics. ① Integrated geodesign and parametric design: It uses a parametric design approach to generate focal-scale district prototypes by means of a custom procedural algorithm, and applies geodesign to evaluate the performances of design proposals. ② A focus on design flow: It elaborates how to define problems, what information is selected, and what criteria are used in making design decisions. ③ Multi-objective optimization: The test case produces indicators from performance modeling and derives principles through a multi-objective computational experiment to inform how the design can be improved. This paper concludes with issues and next steps in modeling urban design and infrastructure systems based on MDO tools.     

The Unseeing State: How Ideals of Modernity Have Undermined Innovation in Africa’s Urban Water Systems

In contrast to the European historical experience, Africa’s urban infrastructural systems are characterised by stagnation long before demand has been saturated. Water infrastructures have been stabilised as systems predominantly providing services for elites, with millions of poor people lacking basic services in the cities. What is puzzling is that so little emphasis has been placed on innovation and the adaptation of the colonial technological paradigm to better suit the local and current socio-economic contexts. Based on historical case studies of Kampala and Nairobi, this paper argues that the lack of innovation in African urban water infrastructure can be understood using Pinch and Bijker’s concept of technological closure, and by looking at water technology from its embedded values and ideology. Large-scale water technology became part of African leaders’ strategies to build prosperous nations and cities after decolonisation and the ideological purpose of infrastructure may have been much more important than previously understood. Water technology had reached a state of closure in Europe and then came to represent modernisation and progress in the colonial context. It has continued to serve such a similar symbolic purpose after independence, with old norms essentially being preserved. Recent sector reforms have defined problems predominantly as of economic and institutional nature while state actors have become ‘unseeing’ vis-á-vis controversies within the technological systems themselves. In order to induce socio-technical innovation towards equality in urban infrastructure services, it will be necessary to understand the broader incentive structure that governs the relevant social groups, such as governments, donors, water suppliers and the consumers, as well as power-structures and political accountability.     

Hydrogen energy

The problem of anthropogenically driven climate change and its inextricable link to our global society's present and future energy needs are arguably the greatest challenge facing our planet. Hydrogen is now widely regarded as one key element of a potential energy solution for the twenty-first century, capable of assisting in issues of environmental emissions, sustainability and energy security. Hydrogen has the potential to provide for energy in transportation, distributed heat and power generation and energy storage systems with little or no impact on the environment, both locally and globally. However, any transition from a carbon-based (fossil fuel) energy system to a hydrogen-based economy involves significant scientific, technological and socio-economic barriers. This brief report aims to outline the basis of the growing worldwide interest in hydrogen energy and examines some of the important issues relating to the future development of hydrogen as an energy vector.     

Transformative innovation policy or how to escape peripheral policy paradox in European research peripheral countries

The research peripheral countries (RPCs) are faced with the need to provide transformative change for long term sustainable development with scarce research and development resources which rests upon strengthening science base and the transformative innovation policy focused on societal and environmental challenges. The European Commission's proposal of a new recovery instrument – the Next Generation EU, incorporating the Recovery and Resilience Facility as a key instrument - is focused on green, sustainable, and digital economies, paving the way for a shift from the standard science, technology, and innovation (STI) policy towards transformative innovation policies which foster innovation focused on systematic change and sustainable socio-technical systems.This research seeks to understand the ways in which STI policy can contribute to the economic resilience and sustainable development of research peripheral countries and how STI policies can respond to new innovation policy paradigms, avoiding Europeanisation of STI policies and, ultimately, a peripheral policy paradox. Overcoming of the periphery paradox in STI policies requires unorthodox policy solutions to avoid inefficient replication of policy measures from advanced countries which pertain to science – industry cooperation to foster high tech industries and frontier research.This research proposes a new STI policy approach, based on interactions and interdependencies between standard STI policies for fostering scientific research and science-industry cooperation through transformative innovation policies. This policy allows for an experimental approach to policy-making, finding a way to best suit the national socio-economic context for the gradual replacement of the established socio-technical regime towards sustainable transitions. The fourth component of the new STI policy approach is the concept of the mission-oriented policy, which draws on frontier knowledge and large investments. Both new policy paradigms are discussed in order to highlight the pros and cons of their application in RPCs with regards to research capacities, socio-economic regimes/landscapes, and societal challenges.     

城市雕塑在中国新型城镇化建设中不容忽视

通过梳理中国城市雕塑在城镇化中的发展历程。阐述新型城镇化中城市雕塑的价值和建设理念。今天城镇化基础设施等物质文明建设已取得的成就，提出在今后的城镇化建设中城乡精神文明建设更加不容忽视，城市雕塑建设应当更加理性规划、合理布局，才能起到助推城镇化的作用。应从三个 方面给予重视，第一，面对城市建设趋同现象，城市雕塑建设对城乡特色的彰显需明确各自定位；第二，在助力我国中西部及城乡协调发展中，城市雕塑应注重整体规划与多样化建设；第三，在乡村振兴过程中，城市雕塑与公共艺术相互配合，更好地与乡村环境、景观相融合，助力小城市、小城镇、新型农村社区等建设，调动其在乡村振兴的新型城镇化建设中的力量。     

Mind the gap: The AURORAL ecosystem for the digital transformation of smart communities and rural areas

Rural areas play a crucial role in addressing challenges related to climate change, food provision, biomass, and energy. At the same time, digital solutions have proven essential in improving safety, quality of life, and resilience in daily life. However, the lower population density and the lack of digital infrastructure in such rural areas make it difficult to develop technology-driven private businesses and public services. This can negatively impact socio-economic indicators and hinder the development of new services to cover peoples’ needs. For this reason, in this document, we seek to provide a stronger focus on rural regions in digitalization efforts and create new opportunities for rural communities. For that, we analyze the barriers and needs of the rural environment and present AURORAL, a digital service platform designed to meet the needs and contexts of rural areas. This ecosystem, comprising sustainable and multi-interoperable apps and services, can help communities succeed in innovation and smart transformation, providing the necessary infrastructure to facilitate long-lasting social, environmental, and economic benefits by prioritizing openness, interoperability, and decentralization. On the principle that the full potential of these technologies can only be realized when they are integrated into societal and economic activity and organization, AURORAL aims to promote economic growth and digitalization in the rural domain and contribute to bridging the digital divide between rural and urban areas.