Migration plays a crucial role in urban growth. Over time, individuals opting to relocate led to vast metropolises like London and Paris during the Industrial Revolution, Shanghai and Karachi during the last decades and thousands of smaller settlements. Here, we analyze the impact that migration has on population redistribution. We use a model of city-to-city migration as a process that occurs within a network, where the nodes represent cities, and the edges correspond to the flux of individuals. We analyze metrics characterizing the urban distribution and show how a slight preference for some destinations might result in the observed distribution of the population.
The objective of this article is to understand processes and mechanisms that make urban policy instruments legitimize public interest being obscured by the hegemony of private actors, suggesting dissonances and distancing of these instruments from the urban plans and projects proposed for Recife (2000-2023). These mismatches and their prevalence are exemplified in the production of the city that accompanies the river and sea coast in the central area, assuming that investments by private actors in the historic centres are directly linked to and favoured by public policies (or their inability to counterbalance real estate advancement), resulting in the valuation of land not being the object of fair redistribution driven by urban policy. It is based on the fact that the urban space is the object and result of conflict and socio-spatial inequality, and that within the framework of a monopolistic and oligopolistic capitalist practice, the interests of real estate developers and developers, and the privatization of public lands, result in pressures from private agents on the State and society.
Aesthetics of cities. City planning and beautifying, Urban groups. The city. Urban sociology
Portugal's early seaside holiday camps emerged prior to the Estado Novo era, serving as summer destinations for underprivileged children even before the implementation of national educational programs. Educational and charitable associations, supported by private philanthropy and the working class, played a pivotal role in the development of these facilities. Newspapers and cooperatives like Voz do Operário spearheaded social initiatives to address the challenges of the late nineteenth century, targeting workers and their families. These initiatives involved hundreds of children each summer, primarily between June and October, for the care of childhood tuberculosis and the recreation of young guests. These projects found space in existing buildings or gave rise to new buildings along a mostly pristine coastline, often at a considerable distance from urban centers. A significant example is the O Século seaside children's holiday camp, funded by private and public funds, operational since 1927 in S. Pedro do Estoril, between Lisbon and the renowned Cascais. The project went through at least three construction phases, influencing city public life and benefiting from the support of Lisbon’s famous Feira Popular, in operation until a few years ago. Archival documents, historical photographs, and blueprints testify to the evolution of these facilities over time. Transformations between 1944 and 1945 highlight the importance of this camp in the collectivity, its strategies of funding, and its needs, staff, and the children it hosted. Over the years, many of these facilities disappeared due to the tourism expansion in the area, unlike the case of O Século, which still partly continues programs dedicated to childhood.
Architectural drawing and design, Aesthetics of cities. City planning and beautifying
Existing operations research (OR) models and tools play indispensable roles in smart-city operations, yet their practical implementation is limited by the complexity of modeling and deficiencies in optimization proficiency. To generate more relevant and accurate solutions to users' requirements, we propose a large language model (LLM)-based agent ("City-LEO") that enhances the efficiency and transparency of city management through conversational interactions. Specifically, to accommodate diverse users' requirements and enhance computational tractability, City-LEO leverages LLM's logical reasoning capabilities on prior knowledge to scope down large-scale optimization problems efficiently. In the human-like decision process, City-LEO also incorporates End-to-end (E2E) model to synergize the prediction and optimization. The E2E framework be conducive to coping with environmental uncertainties and involving more query-relevant features, and then facilitates transparent and interpretable decision-making process. In case study, we employ City-LEO in the operations management of e-bike sharing (EBS) system. The numerical results demonstrate that City-LEO has superior performance when benchmarks against the full-scale optimization problem. With less computational time, City-LEO generates more satisfactory and relevant solutions to the users' requirements, and achieves lower global suboptimality without significantly compromising accuracy. In a broader sense, our proposed agent offers promise to develop LLM-embedded OR tools for smart-city operations management.
The generation of large-scale urban layouts has garnered substantial interest across various disciplines. Prior methods have utilized procedural generation requiring manual rule coding or deep learning needing abundant data. However, prior approaches have not considered the context-sensitive nature of urban layout generation. Our approach addresses this gap by leveraging a canonical graph representation for the entire city, which facilitates scalability and captures the multi-layer semantics inherent in urban layouts. We introduce a novel graph-based masked autoencoder (GMAE) for city-scale urban layout generation. The method encodes attributed buildings, city blocks, communities and cities into a unified graph structure, enabling self-supervised masked training for graph autoencoder. Additionally, we employ scheduled iterative sampling for 2.5D layout generation, prioritizing the generation of important city blocks and buildings. Our approach achieves good realism, semantic consistency, and correctness across the heterogeneous urban styles in 330 US cities. Codes and datasets are released at https://github.com/Arking1995/COHO.
Alessandra Battisti, Marco Antonini, Angela Calvano
et al.
Clean Energy for All Europeans, Green Deal and Fit for 55 at European level and the Piano Nazionale Integrato per l’Energia e il Clima have identified essential decarbonisation goals that are achievable by broadening the audience of actors involved and the ability to innovate in terms of the evolution of products/services and production processes. In this sense, decentralised energy production technologies together with Renewable Energy Communities (RECs) and bottom-up initiatives play a strategic role in the establishment of local energy systems. The objective of the paper is to illustrate these dynamisms within the territorial system, and the characteristics of local initiatives and RECs as means of energy transition and economic development.
Aesthetics of cities. City planning and beautifying, Architectural drawing and design
The following article presents a very brief review of the impact of the art institution Documenta on the Athenian urban environment aims to give an answer to the question of how and why the art exhibition “Learning from Athens” gained such popularity in urban and economic developers, locally and globally, that has not yet led to enough critical discussion on the cultural, and political researchers. The article approaches two views on this impact. One linked to the Athenian urban ruins of the Greek economic recession through which emerged a new (exotic) touristic destination to the European periphery. And the other linked to the politics of the Creative City which function as the main strategy of the present Athens cultural-led gentrification including heritage and planning politics, real estate, touristic, entertainment, and creative industries. The article is setting up a number of important questions to cultural and political researchers about city rebrand processes and the generated change and innovation produced; the social inequalities in particular.
Aesthetics of cities. City planning and beautifying
The emergence of smart cities demands harnessing advanced technologies like the Internet of Things (IoT) and Artificial Intelligence (AI) and promises to unlock cities' potential to become more sustainable, efficient, and ultimately livable for their inhabitants. This work introduces an intelligent city management system that provides a data-driven approach to three use cases: (i) analyze traffic information to reduce the risk of traffic collisions and improve driver and pedestrian safety, (ii) identify when and where energy consumption can be reduced to improve cost savings, and (iii) detect maintenance issues like potholes in the city's roads and sidewalks, as well as the beginning of hazards like floods and fires. A case study in Aveiro City demonstrates the system's effectiveness in generating actionable insights that enhance security, energy efficiency, and sustainability, while highlighting the potential of AI and IoT-driven solutions for smart city development.
Manmeet Singh, Nachiketa Acharya, Sajad Jamshidi
et al.
Urban downscaling is a link to transfer the knowledge from coarser climate information to city scale assessments. These high-resolution assessments need multiyear climatology of past data and future projections, which are complex and computationally expensive to generate using traditional numerical weather prediction models. The city of Austin, Texas, USA has seen tremendous growth in the past decade. Systematic planning for the future requires the availability of fine resolution city-scale datasets. In this study, we demonstrate a novel approach generating a general purpose operator using deep learning to perform urban downscaling. The algorithm employs an iterative super-resolution convolutional neural network (Iterative SRCNN) over the city of Austin, Texas, USA. We show the development of a high-resolution gridded precipitation product (300 m) from a coarse (10 km) satellite-based product (JAXA GsMAP). High resolution gridded datasets of precipitation offer insights into the spatial distribution of heavy to low precipitation events in the past. The algorithm shows improvement in the mean peak-signal-to-noise-ratio and mutual information to generate high resolution gridded product of size 300 m X 300 m relative to the cubic interpolation baseline. Our results have implications for developing high-resolution gridded-precipitation urban datasets and the future planning of smart cities for other cities and other climatic variables.
Pedro Rito, Ana Almeida, Andreia Figueiredo
et al.
This article presents the deployment and experimentation architecture of the Aveiro Tech City Living Lab (ATCLL) in Aveiro, Portugal. This platform comprises a large number of Internet-of-Things devices with communication, sensing and computing capabilities. The communication infrastructure, built on fiber and Millimeter-wave (mmWave) links, integrates a communication network with radio terminals (WiFi, ITS-G5, C-V2X, 5G and LoRa(WAN)), multiprotocol, spread throughout 44 connected points of access in the city. Additionally, public transportation has also been equipped with communication and sensing units. All these points combine and interconnect a set of sensors, such as mobility (Radars, Lidars, video cameras) and environmental sensors. Combining edge computing and cloud management to deploy the services and manage the platform, and a data platform to gather and process the data, the living lab supports a wide range of services and applications: IoT, intelligent transportation systems and assisted driving, environmental monitoring, emergency and safety, among others. This article describes the architecture, implementation and deployment to make the overall platform to work and integrate researchers and citizens. Moreover, it showcases some examples of the performance metrics achieved in the city infrastructure, the data that can be collected, visualized and used to build services and applications to the cities, and, finally, different use cases in the mobility and safety scenarios.
Emily Muller, Emily Gemmell, Ishmam Choudhury
et al.
The interactions of individuals with city neighbourhoods is determined, in part, by the perceived quality of urban environments. Perceived neighbourhood quality is a core component of urban vitality, influencing social cohesion, sense of community, safety, activity and mental health of residents. Large-scale assessment of perceptions of neighbourhood quality was pioneered by the Place Pulse projects. Researchers demonstrated the efficacy of crowd-sourcing perception ratings of image pairs across 56 cities and training a model to predict perceptions from street-view images. Variation across cities may limit Place Pulse's usefulness for assessing within-city perceptions. In this paper, we set forth a protocol for city-specific dataset collection for the perception: 'On which street would you prefer to walk?'. This paper describes our methodology, based in London, including collection of images and ratings, web development, model training and mapping. Assessment of within-city perceptions of neighbourhoods can identify inequities, inform planning priorities, and identify temporal dynamics. Code available: https://emilymuller1991.github.io/urban-perceptions/.
El paisaje es entendido como una producción cultural, una manera de ver y representar al mundo circundante. Desde esta perspectiva, el presente artículo pretende explorar las representaciones del paisaje que ayudaron a forjar la imagen del México decimonónico. Tomando en cuenta lo anterior, se seleccionaron obras de viajeros que van desde especialistas como Humboldt, hasta aficionados. En dichos textos, se abordaron aspectos como el papel de la religión en el paisaje, la representación de México como el cuerno de la abundancia, la incipiente perspectiva científica, la representación de la tropicalidad, y la producción estética del paisaje mexicano. Las representaciones del paisaje presentadas en este artículo, corresponden a la perspectiva de Occidente, la cual no tomaba en cuenta a otros modelos culturales. Estas representaciones dieron lugar al paisaje mexicano, que no era americano ni europeo, el cual sirvió en la construcción del nacionalismo mexicano.
Aesthetics of cities. City planning and beautifying
Eszter Bokányi, Sándor Juhász, Márton Karsai
et al.
Millions commute to work every day in cities and interact with colleagues, customers, providers, friends, and strangers. Commuting facilitates the mixing of people from distant and diverse neighborhoods, but whether this has an imprint on social inclusion or instead, connections remain assortative is less explored. In this paper, we aim to better understand income sorting in social networks inside cities and investigate how commuting distance conditions the online social ties of Twitter users in the 50 largest metropolitan areas of the United States. Home and work locations are identified from geolocated tweets that enable us to infer the socio-economic status of individuals. Our results show that an above-median commuting distance in cities is associated with more diverse individual networks in terms of connected peers and their income. The degree that distant commutes link neighborhoods of different socio-economic backgrounds greatly varies by city size and structure. However, we find that above-median commutes are associated with a nearly uniform, moderate reduction of social tie assortativity across the top 50 US cities suggesting a universal role of commuting in integrating disparate social networks in cities. Our results inform policy that facilitating access across distant neighborhoods can advance the social inclusion of low-income groups.
The bicycle is a low-cost means of transport linked to low risk of COVID-19 transmission. Governments have incentivized cycling by redistributing street space as part of their post-lockdown strategies. Here, we evaluate the impact of provisional bicycle infrastructure on cycling traffic in European cities. We scrape daily bicycle counts spanning over a decade from 736 bicycle counters in 106 European cities. We combine this with data on announced and completed pop-up bike lane road work projects. On average 11.5 kilometers of provisional pop-up bike lanes have been built per city. Each kilometer has increased cycling in a city by 0.6%. We calculate that the new infrastructure will generate $2.3 billion in health benefits per year, if cycling habits are sticky.
Steven Kisseleff, Wallace A. Martins, Hayder Al-Hraishawi
et al.
The concept of Smart Cities has been introduced as a way to benefit from the digitization of various ecosystems at a city level. To support this concept, future communication networks need to be carefully designed with respect to the city infrastructure and utilization of resources. Recently, the idea of 'smart' environment, which takes advantage of the infrastructure for better performance of wireless networks, has been proposed. This idea is aligned with the recent advances in design of reconfigurable intelligent surfaces (RISs), which are planar structures with the capability to reflect impinging electromagnetic waves toward preferred directions. Thus, RISs are expected to provide the necessary flexibility for the design of the 'smart' communication environment, which can be optimally shaped to enable cost- and energy-efficient signal transmissions where needed. Upon deployment of RISs, the ecosystem of the Smart Cities would become even more controllable and adaptable, which would subsequently ease the implementation of future communication networks in urban areas and boost the interconnection among private households and public services. In this paper, we describe our vision of the application of RISs in future Smart Cities. In particular, the research challenges and opportunities are addressed. The contribution paves the road to a systematic design of RIS-assisted communication networks for Smart Cities in the years to come.
Joao Meirelles, Fabiano Ribeiro, Gabriel Cury
et al.
Global sustainability relies on our capacity of understanding and guiding urban systems, and their metabolism, in an adequate way. It has been proposed that bigger and denser cities are more resource-efficient than smaller ones because they tend to demand less infrastructure, consume less fuel for transportation and less energy for cooling or heating in per capita terms. This hypothesis is also called Brand's Law. But as cities get bigger, denser and more resource-efficient they also get richer. And richer inhabitants buy more, increasing its resource demand and associated environmental impacts. To fully understand the nexus between population size or density and the environmental impacts generated by a city, one needs to take into account both direct and indirect impacts. Facing the lack of empirical evidence on consumption-based emissions for cities, in this paper we propose a mean-field model to derive emissions estimations out of well-established urban metrics (city size, density, infrastructure, wealth). We aim at understanding if Brand's law holds true after adopting a consumption-based approach to urban emissions. The proposed model shows that when considering consumption-based emissions, in most cases Brand's law falls apart - bigger cities have greater purchase power, resulting in greater consumption of goods and higher associated GHG emissions. The model also shows that decoupling between population and emissions is possible and dependent on the decoupling level between income and impacts. In order to achieve it, a shift in consumption patterns of most cities is of utmost importance, so that each new monetary unit added to the GDP, or any other income variable for that effect does not result in a proportional increase in GHG emissions.
In this work, we show the importance of considering a city's shape, as much as its population density figures, in urban transport planning. We consider in particular cities that are circular (the most common shape) compared to those that are rectangular: For the latter case we show greater utility for a single line light rail/tram system. We introduce the new concepts of Infeasible Regions and Infeasibility Factors, and show how to calculate them numerically and (in some cases) analytically. A particular case study is presented for Galway City.
Challenges due to the rapid urbanization of the world -- especially in emerging countries -- range from an increasing dependence on energy, to air pollution, socio-spatial inequalities, environmental and sustainability issues. Modelling the structure and evolution of cities is therefore critical because policy makers need robust theories and new paradigms for mitigating these problems. Fortunately, the increased data available about urban systems opens the possibility of constructing a quantitative 'science of cities', with the aim of identifying and modelling essential phenomena. Statistical physics plays a major role in this effort by bringing tools and concepts able to bridge theory and empirical results. This article illustrates this point by focusing on fundamental objects in cities: the distribution of the urban population; segregation phenomena and spin-like models; the polycentric transition of the activity organization; energy considerations about mobility and models inspired by gravity and radiation concepts; CO2 emitted by transport; and finally, scaling that describes how various socio-economical and infrastructures evolve when cities grow.