Online Demo: NYC TaxiFlow (based on ~177 million taxi trip records in 2009)

1) Aggregated pickup locations snapped to DCPLION street segments [link]

2) Aggregated drop-off locations snapped to DCPLION street segments [link]

3) Aggregated pickup locations using 2000 Census tracts [link]

4) Aggregated drop-off locations using 2000 Census tracts [link]

Notes:

A) All symbolized values are based on 10-level natural-break classification of the TOT field in the respective dataset.

B) Fields H0 to H23 denote the hourly values from hour 0 to hour 23 in a day. Charting function will be provided in the next version.

 

5) Visualizing taxiflow among 71 NYC Community Districts (2009) using JFlowMap (applet-based)

Hourly: [FlowMap View] [FlowStrates View]

Aggregated: [FlowMap View] [FlowStrates View]

6) Visualizing top 1000 TaxiFlow pairs (2009) using JFlowMap (applet-based)

Hourly: [FlowMap View] [FlowStrates View]

Note: when an applet is loaded in FlowMap view, click the [Settings] button to bring a setting dialog. Click the [animation] tab to play the hourly animation of taxi trip counts of the top 1000 pairs (408 census blocks).

 

LGA case study of NYC TaxiFlow

Using bctcb2000 code 40331001001 in NYC Census Tract 2000 dataset with 101,499 (out of ~200 millions) taxi trips in 2009.

1) Locations: Low Resolution [Pickup Locations] [Drop-Off Locations] High Resolution [Pickup Locations] [Drop-Off Locations]

2) Google Map of the Study Area: [Image]

3) Hourly trip distributions: [Link]

4) Charting: [Distance-Time] [Distance - Fare] [Time - Fare] [Fare - Tip]

Note: Charting uses the first 32,000 samples due to Microsoft Excel Limits.

 

Shortest-Path Based Trip Counts over DCPLION Street Segments [2009]

 

Online Demo: Visual Exploration of Large-Scale Species Distribution Data

URL http://geoteci.engr.ccny.cuny.edu/birds30s/BirdsQuest.html

Related Publication:

 

1.       Jianting Zhang (2012). A high-performance web-based information system for publishing large-scale species range maps in support of biodiversity studies. Ecological Informatics 8: 68-77. [Link][Local Copy]

2.      Jianting Zhang, Michael Gertz, Le Gruenwald, Efficiently Managing Large-Scale Raster Species Distribution Data in PostgreSQL. Proceedings of ACM-GIS09, Nov. 4-6, Seattle, WA. (doi: 10.1145/1653771.1653815). [Link][Local Copy]

3. Jianting Zhang, Efficiently managing large scale species range maps in a spatial database environment, Proceedings of 17th International Conference on GeoInformatics, Aug 12-14, 2009, Fairfax, VA. (DOI: 10.1109/GEOINFORMATICS.2009.5293395). [Link][Local Copy]

 

Online Demo: Visual Exploration of Large-Scale Geospatial Rasters

URL: http://geoteci.engr.ccny.cuny.edu/rasterexplorer/comgeotiling/TestOverlay.html

 

Related Publications

1.     Jianting Zhang and Simin You. Supporting Web-based Visual Exploration of Large-Scale Raster Geospatial Data Using Binned Min-Max Quadtree. Proceedings of the 22nd International Scientific and Statistical Database Management Conference (SSDBM10). June 30-July 2 2010, Heidelberg, Germany. Springer Lecture Notes in Computer Science (LNCS) 6187, pp. 379-396. (10.1007/978-3-642-13818-8_27) [Link][Local Copy]

2.     Jianting Zhang and Simin You. Dynamic Tiled Map Services: Supporting Query-Based Visualization of Large-Scale Raster Geospatial Data. Proceedings of the 1st International Conference on Computing for Geospatial Research & Application (COM.Geo10). June 21-23, Washington DC. USA. ACM Digital Library DOI 10.1145/1823854.1823877. [Link][Local Copy]

 

Open Source Software: VD-RS [snapshots]

URL: http://geoteci.engr.ccny.cuny.edu/pub/vdmrsv10.zip (11M)

 

Related Publications

1.      Jianting Zhang, Le Gruenwald, Michael Gertz, VDM-RS: A Visual Data Mining System for Exploring and Classifying Remotely Sensed Images. Computers & Geosciences 35(9), 1827-1836. [doi:10.1016/j.cageo.2009.02.006]. ISSN 0098-3004. [Link][Local Copy]

2.      Jianting Zhang, Le Gruenwald, Opening the Black Box of Feature Extraction: Incorporating Visualization into High-Dimensional Data Mining Processes. Proceedings of the IEEE International Conference on Data Mining (ICDM06), Hong Kong, China, Dec. 2006, pp. 1188-1192. ISBN 0-7695-2701-7. [doi: 10.1109/ICDM.2006.121]

 

Open Source Software: LEEASP [snapshots]

URL: http://geoteci.engr.ccny.cuny.edu/pub/LEEASPV10.zip (7M)

Related Publications

Jianting Zhang, Le Gruenwald, 2008. Embedding and Extending GIS for Exploratory Analysis of Large-Scale Species Distribution Data. Proceedings of ACM-GIS'08, November 5-7. Irvine, CA. ISBN 978-1-60558-323-5. (doi: 10.1145/1463434.1463470) (Full paper acceptance rate 38/193) [Link][Local Copy]

 

Open Source Software: GBD-Explorer [snapshots]

URL: http://geoteci.engr.ccny.cuny.edu/pub/GBDV10.zip (55M)

Related Publications

Jianting Zhang, Deana D. Pennington, Xianhua Liu, 2007. GBD-Explorer: Extending Open Source Java GIS for Exploring Ecoregion-Based Biodiversity Data. Ecological Informatics Journal, 2(2), pp. 94-102. ISSN: 1574-9541. (doi:10.1016/j.ecoinf.2007.05.001)