The metabolic urban network: Urbanisation as hierarchically ordered space of flows

Cities ◽  
2021 ◽  
Vol 109 ◽  
pp. 103029
Author(s):  
Luis Inostroza ◽  
Harald Zepp
Keyword(s):  
Urban Network ◽  
Ordered Space ◽  
Space Of Flows

The Role of the City in Merovingian Francia

2020 ◽  
pp. 581-610
Author(s):  
S. T. Loseby
Keyword(s):  
Roman Empire ◽  
Urban Communities ◽  
Late Antiquity ◽  
Building Blocks ◽  
Urban Network ◽  
City Councils ◽  
Royal Courts ◽  
Range Of Functions ◽  
Fierce Competition

The Merovingians inherited an urban network from the Roman Empire that remained substantially intact. Although Gallic cities had long been declining in extent and sophistication, during late antiquity their landscapes were adapted to contemporary priorities through the provision of walls and churches, and their politics was transformed by the emergence of bishops as leaders of urban communities. When the upper tiers of imperial administration disappeared, this equipped the vast majority of cities to survive as the basic building blocks of Merovingian kingdoms that were initially conceived as aggregations of city–territories. In ruling through their cities, the Merovingians expanded upon existing mechanisms for the extraction of taxes and services, while relying on centrally appointed bishops and counts rather than city councils for the projection of their authority. This generated fierce competition between kings for control of cities and among local elites for positions of power within them. In the later Merovingian period, however, the significance of cities diminished as stable territorial kingdoms emerged, political practice was centralized around the royal courts, and the Roman administrative legacy finally disintegrated. But the cities remained preeminent religious centers, and, with the beginnings of economic revival, continued to perform a range of functions unmatched by other categories of settlement.

Patronage of urban commercial clusters: A network-based extension of the Huff model for balancing location and size

2017 ◽  
Vol 45 (3) ◽  
pp. 508-528 ◽  
Author(s):  
Andres Sevtsuk ◽  
Raul Kalvo
Keyword(s):  
Spatial Configuration ◽  
Analysis Tool ◽  
Spatial Networks ◽  
Urban Network ◽  
Household Level ◽  
New Town ◽  
New Towns ◽  
Public Facilities ◽  
User Access ◽  
Retail Demand

We introduce a version of the Huff retail expenditure model, where retail demand depends on households’ access to retail centers. Household-level survey data suggest that total retail visits in a system of retail centers depends on the relative location pattern of stores and customers. This dependence opens up an important question—could overall visits to retail centers be increased with a more efficient spatial configuration of centers in planned new towns? To answer this question, we implement the model as an Urban Network Analysis tool in Rhinoceros 3D, where facility patronage can be analyzed along spatial networks and apply it in the context of the Punggol New Town in Singapore. Using fixed household locations, we first test how estimated store visits are affected by the assumption of whether shoppers come from homes or visit shops en route to local public transit stations. We then explore how adjusting both the locations and sizes of commercial centers can maximize overall visits, using automated simulations to test a large number of scenarios. The results show that location and size adjustments to already planned retail centers in a town can yield a 10% increase in estimated store visits. The methodology and tools developed for this analysis can be extended to other context for planning and right-sizing retail developments and other public facilities so as to maximize both user access and facilities usage.

Urban network of China from the perspective of population mobility: Three-dimensional co-occurrence of nodes and links

2021 ◽  
pp. 0308518X2199781
Author(s):  
Xinyue Luo ◽  
Mingxing Chen
Keyword(s):  
Three Dimensional ◽  
Geographical Distance ◽  
Two Dimensional ◽  
Population Mobility ◽  
Urban Network ◽  
Urban Networks ◽  
Low Level ◽  
Medium Level ◽  
High Level ◽  
External Connections

The nodes and links in urban networks are usually presented in a two-dimensional(2D) view. The co-occurrence of nodes and links can also be realized from a three-dimensional(3D) perspective to make the characteristics of urban network more intuitively revealed. Our result shows that the external connections of high-level cities are mainly affected by the level of cities(nodes) and less affected by geographical distance, while medium-level cities are affected by the interaction of the level of cities(nodes) and geographical distance. The external connections of low-level cities are greatly restricted by geographical distance.

ANNs Going Beyond Time Series Forecasting: An Urban Network Perspective

2021 ◽  
Vol 59 (5) ◽  
pp. 88-94
Author(s):  
Jane Frances Pajo ◽  
George Kousiouris ◽  
Dimosthenis Kyriazis ◽  
Roberto Bruschi ◽  
Franco Davoli
Keyword(s):  
Time Series ◽  
Time Series Forecasting ◽  
Urban Network

scholarly journals Criminology: Some lines of flight

2021 ◽  
Vol 54 (1) ◽  
pp. 21-33
Author(s):  
Julie Berg ◽  
Clifford Shearing
Keyword(s):  
21St Century ◽  
Energy Systems ◽  
Social Practices ◽  
Smart Phones ◽  
40Th Anniversary ◽  
The Past ◽  
Domain Of Existence ◽  
James Lovelock ◽  
The 1960S ◽  
Space Of Flows

The 40th Anniversary Edition of Taylor, Walton and Young’s New Criminology, published in 2013, opened with these words: ‘The New Criminology was written at a particular time and place, it was a product of 1968 and its aftermath; a world turned upside down’. We are at a similar moment today. Several developments have been, and are turning, our 21st century world upside down. Among the most profound has been the emergence of a new earth, that the ‘Anthropocene’ references, and ‘cyberspace’, a term first used in the 1960s, which James Lovelock has recently termed a ‘Novacene’, a world that includes both human and artificial intelligences. We live today on an earth that is proving to be very different to the Holocene earth, our home for the past 12,000 years. To appreciate the Novacene one need only think of our ‘smart’ phones. This world constitutes a novel domain of existence that Castells has conceived of as a terrain of ‘material arrangements that allow for simultaneity of social practices without territorial contiguity’ – a world of sprawling material infrastructures, that has enabled a ‘space of flows’, through which massive amounts of information travel. Like the Anthropocene, the Novacene has brought with it novel ‘harmscapes’, for example, attacks on energy systems. In this paper, we consider how criminology has responded to these harmscapes brought on by these new worlds. We identify ‘lines of flight’ that are emerging, as these challenges are being met by criminological thinkers who are developing the conceptual trajectories that are shaping 21st century criminologies.

scholarly journals An Efficiency Enhancing Methodology for Multiple Autonomous Vehicles in an Urban Network Adopting Deep Reinforcement Learning

2021 ◽  
Vol 11 (4) ◽  
pp. 1514 ◽  
Author(s):  
Quang-Duy Tran ◽  
Sang-Hoon Bae
Keyword(s):  
Reinforcement Learning ◽  
Traffic Congestion ◽  
Autonomous Vehicles ◽  
Penetration Rate ◽  
Autonomous Vehicle ◽  
Effective Means ◽  
Urban Network ◽  
Learning Agents ◽  
Policy Optimization ◽  
The Impact

To reduce the impact of congestion, it is necessary to improve our overall understanding of the influence of the autonomous vehicle. Recently, deep reinforcement learning has become an effective means of solving complex control tasks. Accordingly, we show an advanced deep reinforcement learning that investigates how the leading autonomous vehicles affect the urban network under a mixed-traffic environment. We also suggest a set of hyperparameters for achieving better performance. Firstly, we feed a set of hyperparameters into our deep reinforcement learning agents. Secondly, we investigate the leading autonomous vehicle experiment in the urban network with different autonomous vehicle penetration rates. Thirdly, the advantage of leading autonomous vehicles is evaluated using entire manual vehicle and leading manual vehicle experiments. Finally, the proximal policy optimization with a clipped objective is compared to the proximal policy optimization with an adaptive Kullback–Leibler penalty to verify the superiority of the proposed hyperparameter. We demonstrate that full automation traffic increased the average speed 1.27 times greater compared with the entire manual vehicle experiment. Our proposed method becomes significantly more effective at a higher autonomous vehicle penetration rate. Furthermore, the leading autonomous vehicles could help to mitigate traffic congestion.

Sign in / Sign up

Export Citation Format

Share Document