Posts Tagged ‘Survey’

Steps into Mapping the Unmapped (Rural Focus) – Mapping on Mount Elgon (Mapping: No Big Deal)

Wednesday, August 11th, 2010

where_election_monitor

[Editor's note: Humorous take on surveying and ground truthing from the neogeography perspective in Africa. Topics include season planning, mental maps, asking for local knowledge, keeping a trip diary, and sharing results back with the surveyed community.]

Republished from Mapping: No Big Deal.

Mapping hardly accessible, rural areas, is always a challenge. Each area differs so you have to tackle it in its own special way. Yet some basic steps are always the same. I have written some of them down.

In July, Mildred and I went mapping on Mount Elgon as contractors for the National Democratic Institute (NDI) on behalf of Map Kibera. They needed information regarding polling stations in the area for their work on election monitoring. The information included geographic location, accessibility – both physical accessibility and the availability of cell phone service, information related to infrastructure of these stations, and speed of travel to each individual station.

Here is how we tackled the problems step by step:

1. Season planning.

The first and most important step in planning the mapping project is season planning. Obviously you want your work to run smoothly, without too many interruptions which is most of the time not the case. Season planning saves time, energy, money and nerves, takes the nature out of the equation, and lets you focus on other – project related problems.

While mapping on Mount Elgon we overlooked this very crucial step because the results were urgently needed. In an ignorant human and naïve researchers manner we  thought we could conquer nature or at least go over every obstacle it put on our way. We should have known better. June and July being the peak of winter, it was cold and raining all the time. We only had a window of six hours per day when we could work, and the other eight hours we tried to save ourselves from the mountain. Because of the rain, roads became impassable and everything came to a standstill. I can comfortably say we lost at least two to three days of mapping because of the rain and as a result we lost money.

Continue reading at Mapping: No Big Deal . . .

Google Maps Elevation Web Services (Google)

Thursday, March 25th, 2010

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[Editor’s note: A free, sans-API key solution from the web mapping giant for showing elevation (point or along custom path) for Google Maps Mashups either in the v3 API directly or separately as a stand-alone web service. And it returns JSON :) Thanks @lagerratrobe!]

Republished from Google.

The Google Elevation web service provides you a simple interface to query locations on the earth for elevation data. Additionally, you may request sampled elevation data along paths, allowing you to calculate elevation changes along routes.

The Elevation service provides elevation data for all locations on the surface of the earth, including depth locations on the ocean floor (which return negative values). In those cases where Google does not possess exact elevation measurements at the precise location you request, the service will interpolate and return an averaged value using the four nearest locations.

With the Elevation service, you can develop hiking and biking applications, mobile positioning applications, or low resolution surveying applications.

Check the documentation out over at Google . . .

Washington’s Systemic Streets (GGDC, Track29)

Thursday, August 13th, 2009

[Editor’s note: Since moving to Washington, DC, neigh on 7 years ago, I have been fascinated by the system of street names used in the nation’s capital. There’s your normal east-west, north-south grid sectioned into cardinal quadrants in the NW, NE, SW, and SE directions, and then all the state streets, often large Avenues, named after the 50 first-order administrative units that form these United States. The above map shows where these are (some are tiny!), and the entire post, from GreaterGreaterWashington and 29Tracks, has more maps and dialog including a tidbit about the 1st thru 3rd rings being based on number of syllables and the 4th ring based on plants. Thanks Laris!]

Republished from GreaterGreaterWashington and Track Twenty-Nine.
Aug 7, 2009. By Matt Johnson.

Visitors and residents of Washington, DC know, to one degree or another, about the city’s street naming conventions. Most tourists know that we have lettered and numbered streets. And to some degree, they know there is a system, but it doesn’t stop them asking us directions. But most out-of-towners and even many residents don’t understand the full ingenuity of the District’s naming system.

Washington is partially a planned city. The area north of the Potomac and Anacostia Rivers and south of Florida Avenue (originally Boundary Street) is known as the L’Enfant City. This area of Washington was the original city of Washington, laid out by Pierre L’Enfant and Andrew Ellicott. It is comprised of a rectilinear grid with a set of transverse diagonal avenues superimposed. Avenues frequently intersect in circles or squares, and the diagonals create many triangular or bow tie-shaped parks.

Washington is the seat of government of a nation. Believing that the structure of the government should inform the structure of the city, L’Enfant centered the nascent city on the Capitol, home of the Legislative (and at the time, the Judicial) branch of the government, the one the framers held in highest esteem. From this great building radiate the axes of Washington. North and South Capitol Streets form the north-south axis; East Capitol Street and the National Mall form the east-west axis. These axes divide the quadrants.

The axes also provide the basis for the naming and numbering systems. Lettered streets increase alphabetically as they increase in distance both north and south of the Mall and East Capitol Street. Numbered streets increase in number as they increase in distance both east and west of North and South Capitol Streets.

Continue reading at Greater Greater Washington . . .