PositionIT e-News
GIS, GPS, surveying and spatial applications in Southern Africa

 Issue 17, October 2009 

Why pay for data that should be freely available?
by Alex Fortescue, CSIR SAC
Alex FortescueFree and open access to data generally falls under the ambit of a national spatial data infrastructure (SDI) initiative. Governments all over the world are realising the value of national spatial data infrastructures and are generally making major investments to establish them. However, most current literature points to the fact that the implementation of formal NSDI in Africa is extremely poor... (more)
The business of surveying - people, product and profits 
by Robert L Young, Young and Associates Surveying and Mapping
Robert YoungAll of us know someone that started their own business and ended up working at another firm. This is not a failure, it's part of the learning process we go through as adults. If we fail, then what a great learning experience! Millions of words have been written about business, but in my mind they all come down to three concepts: people, product and profits... (more)
The story behind the Tellurometer story
by Mary Wadley von Hirschberg
It is now more than 50 years since the survey world was startled and revolutionised by the invention of the Tellurometer by Trevor Lloyd Wadley. A new book " Trevor Lloyd Wadley - Genius of the Tellurometer" provides a look at the character of the inventor and outlines the circumstances under which the invention was born... (more)
Invention of the Tellurometer - a giant leap forward in surveying
by J R Smith, Hon.Sec. History Group of FIG
Someone came along with a box of electronic tricks, called the Tellurometer, and measured the Isiolo base in about 20 minutes to a very comparable accuracy and similarly that at Malindi. The Isiolo base had suddenly become the last such line to be measured in catenary and a new era had dawned for the surveyor. The traverse from Malindi to Isiolo had been estimated to take between 2 and 2½ years to complete by traditional methods but with the Tellurometer it took just 28 days to cover the 402 miles in 26 traverse legs... (more)
Useable RTK tides
by C J Marx, Land and Marine Surveys

Clint Marx from Land & Marine Surveys, a small survey company specialising in hydrographic and geophysical marine works and high density surveys, has put together a workable method for using RTK tides corrected from a locally measured undulation model - to be applied when published model or geodetic control is unavailable... (more)

Efficient Constrained Delaunay Triangulation implementation
by Thomas Leduc et al

To quantify the impact of increased urbanisation on the peri-urban hydro-systems, it is necessary to design adapted models. Currently, most of the hydrological models, based on classical raster approach, do not take into account the urban artifacts and do not match complex geometries such as urban ones (heterogeneous objects, strong space's partition, roads, pits, buildings etc.). In this article, we present our Triangulated Irregular Network (TIN) based model, that requires a Constrained Delaunay Triangulation preprocessing phase... (more)

Powerful insights from oblique imagery of Africa
Information from AOC

Unlike traditional geospatial information systems that rely only on an orthogonal, or top-down view of an area, Pictometry captures images obliquely, i.e. from an angle, and creates a more natural three-dimensional view so that users can see land features and structures clearly and in their entirety. With only minutes of training, a new user can access detailed imagery of a region and learn to navigate quickly and easily between views of a map to images... (more)

Enabling infrastructure projects to achieve interoperability 
Information from Bentley Systems
Executing infrastructure projects - regardless of the lifecycle phase - has always brought with it significant challenges. This article outlines Bentley's vision for an interoperability platform that is aimed at transcending the spectrum between the point-to-point and centralised-database approaches. The objective is to outline an approach to interoperability that provides the flexibility, scalability, transparency, and economy demanded by actual infrastructure projects... (more)
Mapping for Mozambique's cadastral needs
by Bruno Meyer, CSIR 

The CSIR's Satellite Application Centre (CSIR SAC) was approached by Mozambique's Centro Nacional de Cartografia e Teledeteção (CENACARTA) to produce imagery suited for cadastral mapping to support the Land Component of the MCA-Mozambique Land Tenure Services project, under the National Directorate of Land and Forestry (DNTF). Following previous work done for the centre by CSIR SAC, CENACARTA was eager to extend the current coverage of satellite imagery over the country... (more)  

Kimberley Mine - monitoring project
by Leizel Botha, DBCM and MC Briers, GeoSystems Africa
Senior management at De Beers Consolidated Mines (DBCM) decided in 2006 that the survey and geotechnical monitoring systems at Kimberley Mine's "Big Hole" needed to be augmented by a GPS-based deformation monitoring network. Kimberley Mine, also known as the "Big Hole" said to be the largest hand-dug excavation in the world, was mined between 1871 and 1914... (more)
Crime analysis and the critical role of location intelligence
by Ian Broadbent, Pitney Bowes Business Insight

Crime analysis is a law enforcement function that involves systematic analysis for identifying and analysing patterns and trends in crime and disorder. Information on patterns can help law enforcement agencies deploy resources in a more effective manner, and assist detectives in identifying and apprehending suspects. Crime analysis also plays a role in devising solutions to crime problems, and formulating crime prevention strategies... (more)

Views, comment and opinion

Industry and institute news

Training news
Company and product news

Flash editions
HTML editions
Print editions
RSS feeds
Jobs section
In this issue...
- Why pay for data that should be freely available?
- The business of surveying - people, product and profits
- The story behind the Tellurometer story
- Invention of the Tellurometer
- Useable RTK tides
- Efficient Constrained Delaunay Triangulation implementation
- Powerful insights from oblique imagery of Africa
- Enabling infrastructure projects to achieve interoperability
- Mapping for Mozambique's cadastral needs
- Kimberley Mine - monitoring project
- Crime analysis and the critical role of location intelligence
- Views, comment and opinion
- Industry and institute news
(Flash flip-page edition)
(Flash flip-page edition)
(Flash flip-page edition)
Published by
EE Publishers
P O Box 458
South Africa
Tel 011 543-7000
Fax 011 543-7025

© Copyright 2009

EE Publishers
All rights reserved