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351.
Leinbach, Thomas R. and Brunn, Stanley D. (eds.) Worlds of E-Commerce: Economic, Geographical, and Social Dimensions

Calthorpe, Peter and Fulton, William The Regional City: Planning for the End of Sprawl

Furuseth, Owen J. and Lapping, Mark B. (eds.) Contested Countryside: The Rural-Urban Fringe in North America

Sharp, Joanne P. Condensing the Cold War: Reader's Digest and American Identity

Gleeson, Brendan and Low, Nicholas (eds.) Governing for the Environment: Global Problems, Ethics, and Democracy

Isenberg, Andrew The Destruction of the Bison: An Environmental History, 1750 – 1920

Albert, Donald P., Gesler, Wilbert M. and Levergood, Barbara (eds.) Spatial Analysis, GIS, and Remote Sensing Applications in the Health Sciences

Wright, Dawn J. and Bartlett, Darius J. (eds.) Marine and Coastal Geographical Information Systems

Jankowski, Piotr and Nyerges, Timothy Geographic Information Systems for Group Decision Making: Towards a Participatory Geographic Information Science

Gerber, Rod and Chuan, Goh Kim (eds.) Fieldwork in Geography: Reflections, Perspectives, and Actions

Craige, Betty Jean Eugene Odom: Ecosystem Ecologist and Environmentalist

Lowenthal, David George Perkins Marsh: Prophet of Conservation

Schroeder, Richard Shady Practices: Agroforestry and Gender Practices in The Gambia

Lovell, W. George A Beauty that Hurts: Life and Death in Guatemala

Lichtenberger, Elisabeth Austria: Society and Regions  相似文献   
352.

Accurately mapping a region’s ground water quality depends upon the spatial sampling strategies employed, including where and how often field data are collected. This study compares the relative values of three field sampling strategies for mapping a known migrating plume of volcanic ground water in Sierra Valley, California. The first strategy sampled wells once each year during 1957, 1972, and 1980 (n=63, 45, and 57, respectively) and portrayed spatial–temporal changes in ground water quality more clearly on maps than did two alternative sampling strategies. One of these alternatives, Strategy 2, sampled one well per township per year during 1957, 1972, and 1980 (n=11) and did not detect the migrating plume, despite being a recommended strategy. The other alternative, Strategy 3, frequently sampled in time a small, fixed group of indicator wells (n=13) every four years for the same period, again producing maps with little correlation to the original pattern detected by Strategy 1.  相似文献   
353.

The terms “pure'’and “applied'’were used in connection with mathematics and the sciences in the Nineteenth Century and were affixed to geography no later than 1890. This paper is a review of some early occurrences of the term “applied geography'’in the period 1890–1904.  相似文献   
354.
Abstract

Hydrological alteration within an ice-marginal valley is analysed in relation to flooding by the River Vistula flowing within that valley. Specifically, the analysis covers the period of the last two centuries (up to the present day), making reference to human impacts and natural disasters. Seven topographic maps, as well as digital terrain model (DTM) analysis of the extent of flooded areas are used to evaluate the linkage with historical flood events. Within the ice-marginal valley, flooding processes are found to still play an important role on the floodplain, although human activities have limited these significantly through the construction of embankments. The changing characteristics of floods generated by different mechanisms (e.g. heavy rainfall and ice jams) are also discussed.
Editor D. Koutsoyiannis  相似文献   
355.
356.
Collaborative spatial decision‐making environments in which group members individually and collectively pursue solutions to semi‐structured problems have a unique set of geographic visualization requirements. Group members often pursue diverse strategies as they attempt to solve such problems. As a consequence, numerous mapped representations of alternative solutions are generated. It is difficult to compare and synthesize these results, especially when decision‐makers have little or no previous cartographic training. In this paper, we derive several map types that synthesize representations of alternative solutions to location‐selection problems. These synthetic maps, designed to be accessible to group members, are created by decomposing solutions into a collection of atomic elements that are then placed into an accounting framework. Network map algebra operations are performed within this framework, and the results are accumulated and displayed as maps. Group members can use these maps to identify similar and dissimilar elements of alternative solutions to a problem. Such maps are intended to promote discussion and support group consensus‐building activities.  相似文献   
357.
This article deals with the graphic simplification of a network by schematization. A new method employing a stroke-based and progressive strategy is proposed to generate schematic network maps. This method treats a stroke (which is a long line with segments concatenated together) as a basic unit for the implementation. The procedure is as follows: (a) strokes are formed from line segments, (b) the strokes are re-orientated along grid lines and/or diagonals, and (c) two endpoints and all intersection points on (sub-)strokes are projected onto re-oriented straight lines, and (d) spatial inconsistency is detected and resolved. A methodology for each of these steps is described. This new method has been tested with a set of real-life road network data and evaluated by fractal analysis and empirical study. Experimental results show that this new method is more effective than segment-based methods and is able to produce graphics with great simplicity and clarity. Based on the results obtained, the stroke-based schematization with four primary directions is recommended.  相似文献   
358.
Comparison of thematic maps is an important task in a number of disciplines. Map comparison has traditionally been conducted using cell-by-cell agreement indicators. More recently, other methods have been proposed that take into account not only spatially coincident cells in two maps, but also their surroundings or the spatial structure of their differences. The objective of this article is to propose a framework for map comparison that considers (1) the patterns of spatial association in two maps, in other words, the map elements in their surroundings; (2) the equivalence of those patterns; and (3) the independence of patterns between maps. Two new statistics for the spatial analysis of qualitative data are introduced that are based on the symbolic entropy of the maps. As well, all inferential elements to conduct hypothesis testing are developed. The framework is illustrated using real and simulated maps.  相似文献   
359.
360.
Tephra fallout is an important type of hazard caused by explosive volcanic eruption,and numerical simulation has become a fast and effective approach to assess the dispersion and deposition of tephra fallout.According to the improved 2D diffusion model of Suzuki( 1983),we edited a tephra diffusion program that can run in the Windows system.Based on previous data,we simulated the diffusion scope of the Jinlongdingzi volcanic eruption,which is the latest eruption in the Longgang volcanic cluster.The simulated results are in good agreement with the results from measurement in situ,indicating that the model is reliable and the parameters used in the model are suitable.By using wind profiles of ten years,7,021 simulations under different wind profiles were carried out,and then probabilistic hazard maps of tephra fallout were constructed for tephra thickness thresholds,1cm and 0.5cm.This study can provide an important scientific basis for volcanic hazard analysis,risk mitigation plans and countermeasures in the Longgang volcanic area.  相似文献   
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