tags: GIS

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data (4), PostGIS (3), DC (2), desktop (2), software (2), redistricting (1), hackathon (1), open source (1), library (1), conference (1), geography (1), school (1), uDig (1), render (1), humanitarian (1), PostgreSQL (1), Virginia (1), analysis (1), OpenMoko (1), transportation (1), JavaScript (1), ACPS (1), GPS (1), PostgreQL (1), elementary (1), database (1), demographics (1), address (1), map (1),

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GIS, data, DC, GIS, GIS, desktop, GIS, PostGIS, GIS, software

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DDOT - Multimodal Transportation

District Mobility home page District Mobility is a tool to visualize multimodal transportation system performance within the District of Columbia as part of the District Department of Transportation District Mobility Project. Select a story to find out more.

url: https://districtmobility.org/

type: project, format: page

ACPS Redistricting

Alexandria district blocks

Given the ugly nature of congressional districts, and even one elementary school district in Northern Alexandria, when I heard ACPS was redistricting their elementary schools, I became concerned. I started a project on GitHub to do my own analysis. It's been a fair amount of work, but GIS is fun.

My goal is to model the placement of K-5 students in Alexandria and build districts that minimized distance travelled. Also the assignments must be "stable", where "stable" means there's no 2 kids that would want to swap schools based on distance.

I'm using data from Census, Alexandria GIS, and OpenStreetMap. And I'm using the PostGIS extension to PostgreSQL for spatial analysis.

In an earlier districting project I measured distance as the crow flies, in order to build congressional districts. The issue with that is it completely ignored natural barriers like the Chesapeake Bay. So for this project, I'll use pgRouting to measure distance one would drive to school.

I hope to build a solution a problem that lies between the "single source shortest path" and "all-pairs shortest path" problems. For now I'm leaning towards something like a memoized A* algorithm.

As for the assignments, I'm not sure what to use yet. This problem is unlike k-means because both the location and the capacity of schools is fixed. I'm considering the Stable Marriable Problem (or NRMP), the Assignment Problem, and Hopcroft-Karp Algorithm.

If you're interested, please feel free to fork the project and contribute to it.


DataVirginia - Datathon 2015

data.virginia.gov logo

The 2015 Datathon Challenge is a multi-tiered competition that will bring together teams of students, state employees, and professionals from across the Commonwealth as they create new applications that improve government. Top projects that use state data will be selected during regional events held throughout Virginia and invited to present in September at a final Commonwealth Datathon event in Richmond.   

url: http://data.virginia.gov/datathon-2015/

type: project, format: page


Natural Earth

tags: data, GIS
Natural Earth logo

Natural Earth is a public domain map dataset available at 1:10m, 1:50m, and 1:110 million scales. Featuring tightly integrated vector and raster data, with Natural Earth you can make a variety of visually pleasing, well-crafted maps with cartography or GIS software.

url: http://www.naturalearthdata.com/

type: project, format: page


DC Address Coordinates

tags: database, address, DC, GIS
DC GIS logo

A blog regarding the official address database for Washington, DC. The Master Address Repository (MAR) not only includes addresses but also has information on intersections, blocks, place names and residential units.

url: http://dcaddresscoordinates.blogspot.com/

type: none, format: none


Disruptive Geo | Exploring the disruptive potential of geography

demographic map My name is Joshua Campbell and I am currently a Geographer and GIS Architect at the Humanitarian Information Unit, a division of the Office of the Geographer and Global Issues at the U.S. Department of State. I am also completing a PhD in Geography from the University of Kansas. The core concept for this blog is explained below, but in short it is simply a place where I can post on projects that may be of interest to the broader community. Twitter @disruptivegeo.

url: http://www.disruptivegeo.com/

type: person, format: blog


Paul Ramsey

tags: GIS, PostGIS
the clever elephant Paul Ramsey Victoria, British Columbia, Canada

url: http://blog.cleverelephant.ca/

type: person, format: blog


OSGeo.org | Your Open Source Compass

tags: open source, GIS

Created to support and build the highest-quality open source geospatial software. Our goal is to encourage the use and collaborative development of community-led projects. Join us by signing up to our mailing lists or check out the Getting Started page to become more involved.

url: http://www.osgeo.org/

type: company, format: none


Reprojecting / snapping point-geometries onto a given line-geometry using PostGIS

tags: PostGIS, GIS
a line and several points

Imagine you have a line — a street for example — and point measurements taken while being on that street. Due to certain circumstances — e.g. GPS-coorrdinates are slightly inaccurate –, the coordinates of your measurements are not exactly on the street.

url: http://selectoid.wordpress.com/2009/02/13/reprojecting-snapping-point-geometries-onto-a-given-line-geometry-using-postgis/

type: article, format: blog


Selectoid's Weblog

A detail showing four stars we just created Hi, this is the blog of selectoid

url: http://selectoid.wordpress.com/

type: person, format: blog


tangoGPS - Free user friendly map and gps for Linux || News ||

tags: GPS, GIS, OpenMoko
tangogps logo

tangogps is an easy to use, fast and lightweight mapping application for use with or without GPS.

It runs on any Linux platform from the desktop over eeePC down to phones like the Openmoko Neo.

By default tangoGPS uses map data from the Openstreetmap project. Additionally a variety of other repositories can be easily added.

The maps are automagically downloaded and cached for offline use while you drag or zoom the map.

url: http://www.tangogps.org/

type: project, format: blog


2010 Geospatial Infrastructure Solutions Conference

tags: GIS, conference
gita logo The Geospatial Information & Technology Association (GITA) is the professional association and leading advocate for anyone using geospatial technology to help operate, maintain, and protect the infrastructure, which includes organizations such as utilities, telecommunication companies, and the public sector.

url: http://www.gita.org/gis/

type: none, format: none


OpenLayers: Home

tags: GIS, JavaScript
OpenLayers logo OpenLayers makes it easy to put a dynamic map in any web page. It can display map tiles and markers loaded from any source. MetaCarta developed the initial version of OpenLayers and gave it to the public to further the use of geographic information of all kinds. OpenLayers is completely free, Open Source JavaScript, released under a BSD-style License.

url: http://openlayers.org/

type: project, format: page



tags: GIS, render
mapserver logo MapServer is an Open Source platform for publishing spatial data and interactive mapping applications to the web. Originally developed in the mid-1990’s at the University of Minnesota, MapServer is released under an MIT-style license, and runs on all major platforms (Windows, Linux, Mac OS X).

url: http://mapserver.org/

type: project, format: page



tags: GIS, map
OpenStreetMap logo OpenStreetMap is a free editable map of the whole world. It is made by people like you. OpenStreetMap allows you to view, edit and use geographical data in a collaborative way from anywhere on Earth.

url: http://www.openstreetmap.org/

type: project, format: page


PostGIS : Home

PostGIS logo PostGIS adds support for geographic objects to the PostgreSQL object-relational database. In effect, PostGIS "spatially enables" the PostgreSQL server, allowing it to be used as a backend spatial database for geographic information systems (GIS), much like ESRI's SDE or Oracle's Spatial extension. PostGIS follows the OpenGIS "Simple Features Specification for SQL" and has been certified as compliant with the "Types and Functions" profile.

url: http://postgis.refractions.net/

type: project, format: page


Quantum GIS Project

tags: GIS, desktop, software
Quantum GIS logo Quantum GIS (QGIS) is a user friendly Open Source Geographic Information System (GIS) licensed under the GNU General Public License. QGIS is an official project of the Open Source Geospatial Foundation (OSGeo). It runs on Linux, Unix, Mac OSX, and Windows and supports numerous vector, raster, and database formats and functionalities.

url: http://www.qgis.org/

type: project, format: page


uDig : Home

uDig logo uDig is an open source (LGPL) desktop application framework, built with Eclipse Rich Client (RCP) technology. uDig can be used as a stand-alone application. uDig can be extended with RCP “plug-ins”. uDig can be used as a plug-in in an existing RCP application.

url: http://udig.refractions.net/

type: project, format: page