An algorithm to generate Thiessen diagrams for a set of n points defined in the plane is presented. First, existing proximal polygon computation procedures are reviewed and terms are defined. The algorithm developed here uses a rectangular window within which the Thiessen diagram is defined. The computation of Thiessen polygons uses an iterative walking process whereby the processing starts at the lower left corner of the diagram and proceeds toward the right top corner. The use of a sorted point sequence and dynamical core allocation provide for efficient processing. The presentation is concluded by the discussion of an implementation of the algorithm in a FORTRAN program.相似文献
PARLIAMENTARY GOVERNMENT IN SOUTHERN ASIA, by Sydney D. Bailey. The Hansard Society, London, 1953, in co‐operation with the International Secretariat, Institute of Pacific Relations. Pp. 100. Price 9s.
INDEPENDENT IRAQ, a study in Iraqi Politics since 1932, by Majid Khadduri. Issued under the auspices of the Royal Institute of International Affairs. Oxford University Press. London, New York, Toronto, 1951.
NATIONALISM AND REVOLUTION IN INDONESIA, by George McT. Kahin. Cornell, New York 1952. Pp. 490.
LIBERATION IN SOUTH AMERICA 1806–1827: THE CAREER OF JAMES PAROISSIEN, by R. A. Humphreys. University of London: The Athlone Press, 1952. Pp. XI, 177. Maps and illus. Price 25/‐.
JAPAN IN WORLD HISTORY, by G. B. Sansom. Issued under the auspices of the Japan Institute of Pacific Relations, International Secretariate of the Institute of Pacific Relations, New York, 1951. 94 pp. 相似文献
The article examines the rise of the ‘reactionary modernist’ project that developed after the devastating defeat of the Balkan Wars and which was promoted by the Young Turks by means of articles published in Turkish Homeland, the intellectual platform of the Young Turks. The article argues that the outlines of this project to a large extent shaped the contours of Turkish nationalism then, and that they have hence been constitutive of Turkish nationalism ever since. 相似文献
During prehistory fire-setting was the most appropriate technique for exploiting ore deposits. Charcoal fragments found in the course of archaeological excavations in a small mine called Mauk E in the area of Schwaz/Brixlegg (Tyrol, Austria) are argued to be evidence for the use of this technology. Dendrochronological analyses of the charcoal samples yielded calendar dates for the mining activities showing that the exploitation of the Mauk E mine lasted approximately one decade in the late 8th century BC. Dendrological studies show that the miners utilised stem wood of spruce and fir from forests with high stand density for fire-setting and that the exploitation of the Mauk E mine had only a limited impact on the local forests. 相似文献