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71.
《The Professional geographer》1988,40(1):106-116
software reviews are in this article BMDP/PC CONCEPTS COMPUTERIZED ATLAS EVALUATION OF ALTERNATE PROPOSALS (EAP) EXTRA: EXPRESS TRANSIT ANALYSIS MATC CAD MOTORS TRANSPORTATION PACKAGE PCMAP: Thematic Mapping Software for the IBM Personal Computer, Version 2.3 PLACE TRANPLAN . US-ATLAS 相似文献
72.
Topographic shading curtails the period and complicates the geographic patterns of insolation in mountainous areas. Maps derived from oblique aerial photographs of shadow lines cast by the irregular, mountainous east horizon in Provo, Utah are used as a case study to illustrate an alternative to existing techniques of solar radiation data collection. For study areas of several hundred square kilometers, this method may be superior in resolution and at the same time more error free and economically feasible than other methods. Measurement of solar inputs received at sample stations scattered through the mapped area show that the phenomenon of topographically delayed sunrise has a distinct effect on daily totals of radiation in the manner suggested by the maps. 相似文献
73.
Geographical Information Systems and Geostatistics for Modelling Radioactively Contaminated Land Areas 总被引:2,自引:0,他引:2
The Chernobyl plume contaminated vast lands of Europe with radiocaesium (137Cs) in 1986 because of the deposition of radionuclides on the ground by wet and dry deposition processes. Nevertheless, in a nuclear emergency, contamination data may be very sparse and there is need to make rapid and scientifically supported decisions. Here we analyze the rainfall field, an important precursor of the wet deposition, during the passage of the plume. Thus, estimating rainfall spatial variability can help to identify possible contaminated areas and associated risks when rainfall exceeded a given threshold. In this paper, we show that the conditional probabilities of exceeding threshold rainfall values could be spatially assessed using the mutual benefits of linking geostatistical and geographical information system (GIS) to quantify the evaluation of the risk involved in decision making. In particular, the non-parametric geostatistic technique, termed Indicator Kriging (IK), enables one to efficiently estimate the probability that the true value exceeds the threshold values by means of the indicator coding transform. Afterward, GIS has been used to find the areas probably affected by wash-out (probability >0.5 that rainfall is above a certain threshold). The experimental study has been focused on a test site in Beneventan agroecosystem (Southern Italy) to model the spatial uncertainty over a continuous area from sparse rainfall data. This enabled to generate probability maps delineating area potentially affected by to contamination to be monitored after wet deposition of Chernobyl releases. 相似文献
74.
Seismicity and seismic hazard mapping of northern Algeria: Map of Maximum Calculated Intensities (MCI) 总被引:3,自引:1,他引:2
An earthquake catalogue covering the period1716–2000, comprising 2430 events, has beencompiled for the region lying between3°W-9°E and 31°N-38°N. It results fromraw data of IGN, ISC, USGS and Algeriansources, enabling an input consisting oforigin time H, geographical coordinates(longitude and latitude) and at least one of thefollowing parameters: surface wavemagnitude Ms, body wave magnitude Mb,epicentral intensities Io. Empiricalrelations permit transformations of Mb andMs into Io. The output consists in H,, , Ms, Mb, Io, and focal depth h whichis fixed to 10 km. The number ofevents falls to 1458 characterised by Ms 3.3 and Mb 3.6, or Io III. The fixed depth is suggested by thebest documented Algerian macroseismic mapsthat also lead to an empirical intensityattenuation law. A first application ofthis catalogue allows the drawing up of anupdated Seismicity and a MaximalCalculated Intensities (MCI) Maps ofAlgeria. The MCI map is obtained by usingthe empirical attenuation law: theintensities inferred by the whole eventsconstituting the catalogue are computed atnodes of a 5×5-km grid covering the area ofstudy. The corresponding maximum value isassigned to each node. The MCI map producedthat way gives precise spatial informationin comparison with Maximum ObservedIntensities (MOI) maps obtained in previousmacroseismic studies. This document may beuseful in mapping the seismic hazard inNorthern Algeria, without attachingprobabilities to ground-motionparameters. 相似文献
75.
We describe global bifurcations from the libration points of non-stationary periodic solutions of the restricted three body problem. We show that the only admissible continua of non-stationary periodic solutions of the planar restricted three body problem, bifurcating from the libration points, can be the short-period families bifurcating from the Lagrange equilibria L
4, L
5. We classify admissible continua and show that there are possible exactly six admissible continua of non-stationary periodic solutions of the planar restricted three body problem. We also characterize admissible continua of non-stationary periodic solutions of the spatial restricted three body problem. Moreover, we combine our results with the Déprit and Henrard conjectures (see [8]), concerning families of periodic solutions of the planar restricted three body problem, and show that they can be formulated in a stronger way. As the main tool we use degree theory for SO(2)-equivariant gradient maps defined by the second author in [25].This revised version was published online in October 2005 with corrections to the Cover Date. 相似文献
76.
《The Journal of geography》2012,111(6):243-250
Abstract Teaching students to gain a spatial perspective is one of the most difficult yet important components of geographic education. This paper presents a series of activities designed to develop a more comprehensive understanding of spatial concepts among students in introductory geography courses. The activities and content are most appropriate for high school or university undergraduate students. An evaluation of these activities demonstrates that they enhance the student's spatial perspective and their understanding of the role of spatial concepts in geography. 相似文献
77.
《The Journal of geography》2012,111(2):49-60
Abstract The extant literature on place location learning resolves in varying degrees that place location knowledge (PLK) is deficient in the United States and abroad. This is particularly true for younger school-attending age groups. This study has three main aims: to investigate the validity of that claim in regard to secondary-level students in Dublin by testing their PLK; to assess what characteristics of tested place locations render some sites more visible in students' eyes than others; and to investigate statistically what traits of the respondents shape their PLK. The implications of these findings on geographic education and future research are also discussed. 相似文献
78.
《The Journal of geography》2012,111(4):180-186
Abstract The Geographer at Work by Peter Gould Boston: Routledge &; Kegan Paul, 1985. x and 351 pp., figs., photos, maps, and index. $39.95 cloth; $16.95 paper. Recollections of a Revolution: Geography as Spatial Science by Mark Billinge, Derek Gregory and Ron Martin, eds. New York: St. Martin's Press, 1984. viii and 235 pp., figs., tables, refs., and index. $25.00 cloth. The Role of Place in Literature by Leonard Lutwack Syracuse, NY: Syracuse University Press, 1984. viii and 274 pp., refs., and index. $24.95 cloth. The Essential Landscape: The New Mexico Photographic Survey with Essays by J.B. Jackson. by Steven A. Yates, ed. New Mexico: The University of New Mexico Press, 1985. vii and 147 pp., and photos. $45.00 cloth. Latin America: Case Studies by Richard G. Boehm and Sent Visser, eds. NCGE Pacesetter Series. Dubuque, IA: Kendall/Hunt, 1984. x and 300 pp., figs., tables, photos, maps, apps., refs., and index. $24.95 paper. 相似文献
79.
《The Journal of geography》2012,111(3):164-171
Abstract As computers become commonplace in the nation's schools, interactive maps are finding their way into the geography classroom. Students can use electronic atlases to access information as well as use authoring software to produce their own interactive maps. Does this change in media correspond to better geography education for our children? This article addresses whether using interactive maps for gathering and presenting information can have a positive influence on learning geography content. A two-week experiment was conducted in five 7th grade classrooms. Students in four of the classes researched and produced map products using both traditional and computer-assisted techniques. The fifth class was a control group. A pretest and two post-tests were given to quantitatively assess student learning after each project. Also, students were given a qualitative questionnaire to determine their attitude towards the different techniques. Quantitative results of the study indicate that there was no significant difference in student post-test performance after using each of the techniques, but qualitative results suggest that students prefer using the computer techniques over the traditional methods for gathering and presenting information. 相似文献
80.
主要介绍利用Microsoft Visual Basic.NET编写的地形图分幅编号查询与面积计算程序。通过该程序,根据经纬度坐标或高斯坐标,可查询该点所在各种基本比例尺下的图幅编号、西南图廓点的经纬度坐标以及在不同坐标系下的图幅面积。 相似文献