Links To The Color Figures
In Mei-Po Kwan's Recent Publications

Click "Link Page" for individual link pages with thumbnails.

Kwan's Homepage . Geography Dept Homepage

Mei-Po Kwan and Jiyeong Lee (2004) Geovisualization of Human Activity Patterns Using 3D GIS: A Time-Geographic Approach. In Michael Goodchild and Donald Janelle, eds., Spatially Integrated Social Science, 48-66. New York: Oxford University Press. [Link Page]

Figure 1: Three layers of geographical data used in the study.
Figure 2: Simple activity patterns in space-time.
Figure 3: Activity density patterns in geographic space.
Figure 4: A close-up view of the density surface of home locations of the selected individuals.
Figure 5: Space-time activity density of the non-employment activities of the full-time employed women in the sample.
Figure 6: Gender difference in the space-time density of non-employment activities between the full-time employed women and men in the sample.
Figure 7: Space-time aquarium showing the space-time paths of African and Asian Americans in the sample.
Figure 8: A close-up view of downtown Portland.
Figure 9: Space-time paths based on GPS data collected in Lexington, Kentucky.

Hyun-Mi Kim and Mei-Po Kwan (2003) Space-time Accessibility Measures: A Geocomputational Algorithm with a Focus on the Feasible Opportunity Set and Possible Activity Duration. Journal of Geographical Systems, 5(1):71-91. [Link Page]

Figure 1: Different approaches to evaluating space-time accessibility of individuals.
Figure 2: The effect of the maximum travel time threshold on the space-time prism and potential path area (PPA).
Figure 3: The proposed conceptual framework.
Figure 4: Procedures implemented by the geocomputational algorithm.
Figure 5: The opportunity set delimited in Step 1.
Figure 6: The opportunity set delimited in Step 2.
Figure 7: The opportunity set delimited in Step 3.
Figure 8: The spatial pattern of possible activity duration.

Mei-Po Kwan (2002) Feminist Visualization: Re-envisioning GIS as a Method in Feminist Geographic Research. Annals of the Association of American Geographers, (2002) 92(4):645-661. [Link Page]

Figure 1: The space-time paths of a sample of African-American women in Portland, Oregon.
Figure 2: A detailed view of an area close to downtown Portland, Oregon.

Joe Weber and Mei-Po Kwan (2002) Bringing Time Back In: A Study on the Influence of Travel Time Variations and Facility Opening Hours on Individual Accessibility. The Professional Geographer, 54(2):226-240. [Link Page]

Figure 1: Portland, Oregon, study area.
Figure 2: Weighted opportunity density surface of Portland study area.
Figure 3: Weighted opportunity individual accessibility surface for Portland study area.
Figure 4: Average individual accessibility by distance from the Portland Central Business District (CBD).
Figure 5: Average percent reduction in individual accessibility by distance from the Portland Central Business District (CBD).
Figure 6: Average individual accessibility by distance from twelve regional centers in the Portland metro area.
Figure 7: Average percent reduction in individual accessibility by distance from twelve regional centers in the Portland metro area.

Mei-Po Kwan (2001) Cyberspatial Cognition and Individual Access to Information: The behavioral Foundation of Cybergeography. Environment and Planning B, 28(1):21-37.

Figure 1: A conceptual model of individual accessibility in cyberspace.

Mei-Po Kwan (2000) Interactive Geovisualization of Activity-Travel Patterns Using Three-Dimensional Geographical Information Systems: A Methodological Exploration with a Large Data Set. Transportation Research C, 8:185-203. [Link Page]

Figure 1: Simple activity patterns in space-time.
Figure 2: Activity density patterns in geographic space.
Figure 3: A close-up view of activity patterns in geographic space.
Figure 4a: Space-time activity density of non-employment activities for women employed part-time.
Figure 4b: Space-time activity density of non-employment activities for men employed part-time.
Figure 5: Gender difference in the density of non-employment activities between women and men employed part-time.
Figure 6: Space-time aquarium with the space-time paths of minority groups in the subsample.
Figure 7: A close-up view of downtown Portland from the 3D scene.
Figure 8: Standardized space-time paths.

Mei-Po Kwan (2000) Human Extensibility and Individual Accessibility in Cyberspace: A Multi-Scale Representation Using GIS. IN Donald Janelle and David Hodge, eds., Information, Place, and Cyberspace: Issues in Accessibility, Ch.14, 241-256. Berlin, Springer-Verlag. [Link Page]

Figure 14.1: A two-dimensional representation of the three map layers after transformation.
Figure 14.2: A multi-scale, 3D representation of the individual's space-time path.
Figure 14.3: An extensibility diagram of a set of hypothetical activities.

Mei-Po Kwan (2000) Evaluating Gender Differences in Individual Accessibility: A Study Using Trip Data Collected by the Global Positioning System. Final Report to the Federal Highway Administration. [Link Page]

Figure 1: Space-time prism and potential path area (PPA). PPA in this case is delimited by points A and B. (Adapted from Hanson [1995]).
Figure 2: Location of urban opportunities in exington metropolitan area.
Figure 3: Space-time paths of women without children under 16 in the household.
Figure 4: Derivation of the daily potential path area (DPPA). (Source: Kwan [1999a])

Mei-Po Kwan (1999) Gender, the Home-work Link, and Space-time Patterns of Non-employment Activities. Economic Geography (1999) 75(4), 370-394. [Link Page]

Figure 1: Space-time aquarium for women employed full time.
Figure 2: Space-time aquarium for women employed part time.
Figure 3: Standardized space-time paths for women employed full time.
Figure 4: Standardized space-time paths for men employed full time.
Figure 5: Space-time activity density surface of non-employment activities for women employed full time.
Figure 6: Space-time activity density surface of non-employment activities for men employed full time.
Figure 7: Standardized space-time paths for women employed part time.
Figure 8: Space-time activity density surface of non-employment activities for women employed part time.

Mei-Po Kwan (1999) Gender and Individual Access to Urban Opportunities: A Study Using Space-Time Measures. The Professional Geographer, 51(2):210-227. [Link Page]

Figure 1: Derivation of the daily potential path area (DPPA).
Figure 2: A two-dimensional representation of the daily potential path area (DPPA) of the individual.
Figure 3: The study area and home locations of the individuals in the subsample.
Figure 4: Density surface of urban opportunities in Franklin County, Ohio.

Mei-Po Kwan (1998) Space-time and Integral Measures of Individual Accessibility: A Comparative Analysis Using a Point-Based Framework. Geographical Analysis (1998) 30(3), 191-216. [Link Page]

Figure 1a: Impedance functions for the gravity-type accessibility measures: Power function.
Figure 1b: Impedance functions for the gravity-type accessibility measures: Exponential function
Figure 1c: Impedance functions for the gravity-type accessibility measures: Gaussian function.
Figure 1d: Various impedance functions compared.
Figure 2a: Accessibility surface of the gravity-type measure: POW 1.5.
Figure 2b: Accessibility surface of the gravity-type measure: EXP 0.45.
Figure 3a: Accessibility surface of the cumulative-opportunity measure: CUMR 20.
Figure 3b: Accessibility surface of the cumulative-opportunity measure: CUML 20.
Figure 4a: Accessibility surface of the space-time measure: MHWA.
Figure 4b: Accessibility surface of the space-time measure: FHWA.

Last Updated on July 14, 2005.

Links To The Color Figures In Mei-Po Kwan's Recent Publications

Links To The Color Figures
In Mei-Po Kwan's Recent Publications