Megacity

Summary

A megacity is a very large city, typically with a population of more than 10 million people. Precise definitions vary: the United Nations Department of Economic and Social Affairs in its 2018 "World Urbanization Prospects" report counted urban agglomerations having over 10 million inhabitants. A University of Bonn report held that they are "usually defined as metropolitan areas with a total population of 10 million or more people". Others list cities satisfying criteria of either 5 or 8 million and also having a population density of 2,000 per square kilometre. The terms conurbation, metropolis, and metroplex are also applied to the latter. The total number of megacities in the world varies between different sources: The world had 33 according to the UN (in 2018), 45 according to CityPopulation.de (in 2023), and 44 according to Demographia (in 2022). About half these urban agglomerations are in China and India. The other four

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https://en.wikipedia.org/wiki/Megacity

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Tales from a Robotic World. How Intelligent Machines Will Shape Our Future

Dario Floreano, Nicola Nosengo

Stories from the future of intelligent machines—from rescue drones to robot spouses—and accounts of cutting-edge research that could make it all possible. Tech prognosticators promised us robots—autonomous humanoids that could carry out any number of tasks. Instead, we have robot vacuum cleaners. But, as Dario Floreano and Nicola Nosengo report, advances in robotics could bring those rosy predictions closer to reality. A new generation of robots, directly inspired by the intelligence and bodies of living organisms, will be able not only to process data but to interact physically with humans and the environment. In this book, Floreano, a roboticist, and Nosengo, a science writer, bring us tales from the future of intelligent machines—from rescue drones to robot spouses—along with accounts of the cutting-edge research that could make it all possible. These stories from the not-so-distant future show us robots that can be used for mitigating effects of climate change, providing healthcare, working with humans on the factory floor, and more. Floreano and Nosengo tell us how an application of swarm robotics could protect Venice from flooding, how drones could reduce traffic on the congested streets of mega-cities like Hong Kong, and how a “long-term relationship model” robot could supply sex, love, and companionship. After each fictional scenario, they explain the technologies that underlie it, describing advances in such areas as soft robotics, swarm robotics, aerial and mobile robotics, humanoid robots, wearable robots, and even biohybrid robots based on living cells. Robotics technology is no silver bullet for all the world's problems—but it can help us tackle some of the most pressing challenges we face.

MIT Press2022

On the inefficiency of ride-sourcing services towards urban congestion

Caio Vitor Beojone, Nikolaos Geroliminis

The advent of shared-economy and smartphones made on-demand transportation services possible, which created additional opportunities, but also more complexity to urban mobility. Companies that offer these services are called Transportation Network Companies (TNCs) due to their internet-based nature. Although ride-sourcing is the most notorious service TNCs provide, little is known about to what degree its operations can interfere in traffic conditions, while replacing other transportation modes, or when a large number of idle vehicles is cruising for passengers. We experimentally analyze the efficiency of TNCs using taxi trip data from a Chinese megacity and an agent-based simulation with a trip-based MFD model for determining the speed. We investigate the effect of expanding fleet sizes for TNCs, passengers’ inclination towards sharing rides, and strategies to alleviate urban congestion. We observe that, although a larger fleet size reduces waiting time, it also intensifies congestion, which, in turn, prolongs the total travel time. Such congestion effect is so significant that it is nearly insensitive to passengers’ willingness to share and flexible supply. Finally, parking management strategies can prevent idle vehicles from cruising without assigned passengers, mitigating the negative impacts of ride-sourcing over congestion, and improving the service quality.

2020

The metropolis can be analysed as an infrastructure in perpetual motion, composed of built elements – the system “hardware” – and social networks – the system “software”. The emergence of an overall city-scale infrastructure composed not of a single unit but of intermeshed projects designed by various players has given rise to an observable phenomenon of superdensity. The densification created by the development of these large-scale designs at intermodal hubs is generating new typologies, methodologies and completed projects in response to contemporary urban density. Conceived as an ensemble of services rather than as a built framework, these complex projects generate a paradox between the intrinsic stability of their construction and the instability of their functional programme. This is building within the built environment. Metropolitan development via complex design of this kind involves the production of architecture over another architecture. The city regenerates itself over itself: this is building over the built. Functional obsolescence, infrastructural deterioration, and changing mobility typologies generate the possibility of rethinking the potential of what has already been built. The built sites have been repurposed several times over. This means rethinking the accelerated modification of modes of using buildings and infrastructures by reconfiguring – at various intervention levels – projects from the 1980s and 1990s. How is it possible to intervene yet again without this intervention being the last? The process involves finding new resources for optimising an urban fragment within the existing urban fabric, in places divested of their original purpose. This is rethinking obsolescence through a new urbanism. Optimising the choices available to “building sites of the future” means finding new tools for rethinking dense urban environments. This means reconfiguring a neighbourhood by re-using what already exists, without resorting to façadism or simply gutting existing structures. In an age of “cybercities”, of networked megacities, “open core” development sites need to be created – as a way of facilitating the city’s fragmented transformation via the overlayering of decisions and interventions. The scale of the neighbourhood as urban fragment offers us an entry point for rethinking the existing urban cybercities, by applying tools adapted to a single project comprising various operational sub-ensembles. Unique in terms of their scale and complexity, these designs offer an illuminating field for developing research investigating specific aspects of the architecture profession’s future direction in the 21st century. This is designing complexity.

LIAT / ENSA Paris Malaquais2013