Article in: Environment and Urbanization 

Authors: Shlomo Angel, Jason Parent, and Daniel L. Civco

First published: 2012

Pages: 249-283

Overview:  A key question that has confronted urban planners, policy makers and concerned environmentalists worldwide for some time is whether the fragmentation of the urban landscape is an inherent feature of contemporary cities that must be taken into account in planning for and managing urban expansion, or whether it is a disorderly, wasteful and undesirable form of sprawl that must be brought under control through containment or growth management strategies of one type or another.

Full Text: The Fragmentation of Urban Landscapes (PDF)

Article in: Climate Change and Land Policies

Authors: Shlomo Angel, A.M. Blei, J. Parent, and D.L. Civco

First published: 2011

Pages: 191-210

Overview: A century of density decline in U.S. metropolitan areas has posed structural challenges to the provision of transit services.  This article shows that both the share of the metropolitan populations that can sustain transit and the share of metropolitan ares that can sustain transit have declined substantially over time and are now exceedingly low in most U.S. metropolitan areas.

Full Text: The Fragmentation of Urban Landscapes (PDF)

Article in: Northwestern Interdisciplinary Law Review 4 (1)

Authors: Shlomo Angel, Jason Parent

First published: 2011

Pages: 89-130

Overview: This essay proposes a novel compactness standard “for courts to identify at least the worst cases of gerrymandering and to provide a remedy.” This standard is based on the perception of gerrymandering as aggressive voter exchange, an exchange that distorts the shapes of election districts and renders them non-compact by expelling voters living close by and exchanging them for voters living further away.

Full Text: Non-Compactness and Voter Exchange (PDF)

Article in: Canadian Geographer 54

Authors: Shlomo Angel, Jason Parent, and Daniel L. Civco

First published: 2010

Pages: 441-461

Overview: This essay sheds new light on the meaning and measurement of compactness—one of the most intriguing and least-understood properties of geographic shapes. We articulate a unified theoretical foundation for the study of shape compactness that rests on two simple observations: First, that the circle is the most compact of shapes. And second, that there are 10—and possibly more—distinct geometrical properties of the circle that make it the most compact of shapes. We introduce these 10 properties, illustrate them with real-world examples and define indices associated with these properties that can be calculated using a geographic information system.

Full Text: Ten Compactness Properties of Circles (PDF)

Article in: International Journal of Remote Sensing 30(24)

Authors: Shlomo Angel, David Potere, Annemarie Schneider, and Daniel L. Civco

First published: December, 2009

Pages: 6531-6558

Overview: The goal of this research is to establish the accuracy of the coarse-resolution global urban maps by comparing them to a new, random-stratified global assessment dataset derived from two collections of medium-resolution (28.5 m) Landsat-based city maps and high-resolution Google Earth (GE) imagery.

Full Text: Mapping Urban Area on a Global Scale (PDF)

Article in: Cities 

Authors: Shlomo Angel, Sopon Pornchokchai

First published: May, 1989

Pages: 136‑146

Overview: This pilot study of the size and growth of slum lands in Bangkok from 1974 to 1984 forms part of the general investigation by the Bangkok Land Management Study Team entitled The Land and Housing Markets of Bangkok: Strategies for Public-sector Participation. This paper examines four recent findings from two studies based on air photographs, and draws some initial policy implications from these findings.

Full Text: Bangok Slum Lands (PDF)

Article in: Papers and Proceedings of the Regional Science Association; Vol. 29, Issue 1

Authors: Shlomo Angel, Geoffrey M Hyman

First published: April 1972

Pages: 105-123

Overview: Expenditures on transport in urban areas have been the major explanatory variables in spatial economic theories of the city.

Full Text: Urban Transport Expenditures (PDF)

Article in: Environment and Planning; Vol. 4, No.1

Authors: Shlomo Angel, Geoffrey M Hyman

First published: November 1971

Pages: 99-118

Overview: This paper centers on the development of a geometrical representation of movement and spatial interaction in urban areas, as distinct from the network representation commonly used in modern studies.

Full Text: Urban Spatial Interaction (PDF)

Article in: Papers and Proceedings of the Regional Science Association; Vol.27

Authors: Shlomo Angel, Geoffrey M Hyman

First published: January 1971

Pages: 85-99

Overview: The city is not an undifferentiated terrain and travel does not occur along straight-line paths at constant velocities. Variations in travel velocities at different locations bend the minimum time paths away from regions of high congestion. This paper discusses a transformation of the urban plane into a time surface on which distance corresponds to travel time, and describes the construction of minimum paths and isochrones for various velocity fields.

Full Text: Urban Travel Time (PDF)

Article in: Environment and Planning; Vol. 2, No. 2

Authors: Shlomo Angel, Geoffrey M Hyman

First published: 15 January, 1970

Pages: 211-224

Overview: The city is not an undifferentiated terrain and travel does not occur along straight-line paths at constant velocities. Variations in travel velocities at different locations bend the minimum time paths away from regions of high congestion. This paper discusses a transformation of the urban plane into a time surface on which distance corresponds to travel time, and describes the construction of minimum paths and isochrones for various velocity fields.

Full Text: Urban Velocity Fields (PDF)