June, 2000 (Vol. 29, No. 1)
Refereed Papers
Hickey, R. J. (2000) Slope Angle and Slope Length Solutions for GIS, Cartography, Vol. 29, No. 1.
Mitchell, K. (2000) Critical Success Factors when Publishing Internet Mapping Services, Cartography, Vol. 29, No. 1.
Gordon, S.J. and Montgomery, S.B. (2000) Automated Photogrammetric Adjustment of Historical Coastal Imagery, Cartography, Vol. 29, No. 1.
Marchant, L.R. (2000) The Political Division of Australia 1479 - 1829: The Historical Development of the Western Australian Border (Part One), Cartography, Vol. 29, No. 1.
Slope Angle and Slope Length Solutions for GIS.
Robert Hickey
School of Spatial Sciences
Curtin University of Technology
GPO Box U 1987
Perth 6845, Western Australia
Abstract
The Universal Soil Loss Equation has been used for a number of years to estimate soil erosion. One of its parameters is slope length, however, slope length has traditionally been estimated for large areas rather than calculated. Using data from regular grid DEMs, a method is described in this paper for calculating the cumulative downhill slope length. In addition, methods for calculating slope angle and downhill direction (aspect) are defined. Details of the algorithm and its associated advantages and disadvantages are discussed.
Critical Success Factors when Publishing Internet Mapping Services
Kirk Mitchell
Business Development Manager
Pacific Access Pty Ltd
Abstract
The internet has changed the way cartographer's package and distribute maps. Rather than dwell upon previously well documented technical considerations of Internet mapping, this paper concentrates upon the commercial and logistical factors which determine the success of an Internet mapping service.
Automated Photogrammetric Adjustment of Historical Coastal Imagery
Stuart J. Gordon and S.B. Montgomery
School of Spatial Sciences
Curtin University of Technology
GPO Box U 1987
Perth 6845, Western Australia
Abstract
This paper explains several methodologies for aerotriangulating historical epochs of coastal photography by the partial automatic transfer of control from a fully controlled epoch to several uncontrolled epochs by taking advantage of image matching algorithms. It was expected that an automated process could be used to replace tedious, manual operations undertaken by experienced operators. Automated point measurement was tested for several sets of desktop scanned paper print imagery, separated in age by up to 45 years. The study goals were not realised, however conclusions reflect recommendations for a new approach to the problem with suggestions for an alternate source of control and for improved archiving.
The Political Division of Australia 1479 - 1829:
The Historical Development of the Western Australian Border. (Part One)
Leslie R. Marchant
Chevalier, Ordre National du Mérite; FRGS
Abstract
Three signatories fixed the four early Lines of Demarcation separating the feuding maritime powers as they expanded abroad: Portugal, Spain and the Papacy which acted as arbitrator and peace maker in Christendom.
Two of the early Lines affected Australia. All of the Southern Hemisphere was included in the Portuguese sphere in the first arrangement made in 1479. The next two Lines drawn, the 1493 Papal Line and the 1494 Tordesillas Line, only divided the Atlantic, and are not directly relevant. It was just as well they were not projected through the Poles. The contemporary globes based on Ptolemy were a quarter too small. They lacked the Americas and the Pacific. The discovery of this vast error ushered in a new colonial race to occupy the added portion, necessitating a new eastern line from Pole to Pole. This was arranged at Saragossa in 1529. That Line eventually divided Australia into its Indian Ocean and Pacific halves at 1350 E, which formed the land border of New South Wales.
Britain was content with that border when it annexed the Spanish claim in Australia in 1788, on the eve of the French Revolution and world war. The fall of Napoleon in 1815, launched a new wave of expansion as frontiers in Europe and abroad were re-drawn. There were new players: Britain; the victorious allies; their Congress System in Europe; the infamous Holy Alliance; the Duke of Wellington; Napoleon's beautiful sister's love nest, Restoration France, and the expansionist Dutch were all involved. The outcome of this in Australia was the extension of the New South Wales border to 129 0 E, followed by the occupation of Western Australia.
This will be described in Part 2 which will appear in the next issue of CARTOGRAPHY.
© Leslie R. Marchant
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