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1.
景观生态分类与制图浅议 总被引:12,自引:0,他引:12
程维明 《地球信息科学学报》2002,4(2):61-65
本文在查阅分析大量文献和前人研究的基础上 ,对目前景观生态分类和景观制图作了详细的对比分析 ,认为景观分类需要结合实际区域现状 ,采用逐级分类的方法 ;同时利用 ETM遥感影像为数据源 ,以天山北麓为示范区.研制其土地利用土地覆盖变化的景观类型图。 相似文献
2.
After the survey of pollution sources, a study on surface water quality assessment and forecast is given by means of grey
system method, fuzzy mathematical method and multiple-index method. Based on it, aquatic environment quality features, treatment
measures and environmental strategies of the area are proposed. The quality of aquatic environment of 5 rivers in the Tumen
River area is studied. The results show that the pollution of surface water is serious; water quality of most rivers is between
grade IV and V except the Hunchun River, being higher than grade IV standard; pollution levels of most rivers have been basically
controlled except the of Burhatong River, which is deteriorating gradually. Pollutants of the rivers are comparatively regular,
mainly are SS, COD, BOD, AR-OH, NH3-N. The main pollution trades are chemical fibre industry, pulp and paper making industry and mining industry. If the growth
rate of gross industrial product is higher than 25 percent under the encouraging-model of regional exploitation, the pollutants’
load will overtake the bearing capacity of aquatic environment. Thus some protection program against pollution must be worked
out in order to achieve the harmonious development of economy society and environment.
A project from “Studies on Earlier Stage of Regional Development” of the Chinese Academy of Sciences 相似文献
3.
赵守尧 《成都信息工程学院学报》1994,(1)
本文使用天气学方法,从影响雅砻江区域主汛期降水量的长期预报有关因子出发,再运用数理统计方法反复筛选,仅取3个主要因子:西部青藏高原8个站冬春积温,北部冬季极涡面积指数,南部冬季印缅槽平均强度,建立逐步回归预报方程。结果显示:对主汛期6~9月降水量预报拟合准确率为16/17即约94%。回归分析中发现:尽管西太平洋副热带高压对盆地西部降水有很大影响,盛夏且与高原积温有较密切相关,但由放大范围长时段的青藏高原积温,对于雅砻江区域主汛期降水量的影响超过西太平洋副热高压,因而在逐步回归过程中,副高因子仍被剔除. 相似文献
4.
对武汉区域气象中心并行计算机系统进行了详细地介绍,分析了并行计算机体系结构、网络和存储系统特点;给出了在并行计算机SP上实现数值预报业务并行化的部分结果;对数值预报模式在串、并行编程环境下的结果进行了分析比较。 相似文献
5.
本文论述了土壤形成过程中应具有的一些质的特征,从而证明了流动砂丘并非属于土壤,而只是地质作用的非土形成物或成土母质。在此基础上,对流动砂丘上土壤的形成发育演变方向以及在土壤分类中的地位和命名等问题进行了探讨。 相似文献
6.
利用西安数字地震遥测台网记录的数字地震资料,采用P波初动半周期残差法求得1998年7月临猗5.0级地震前后不同路径的Q(品质因子)值变化,发现在地震发生前Q值为87~203,震后Q值为67~164,震前震中区附近出现明显的高Q值异常。结果表明,地震前的高Q值异常可以作为地震预测的一种手段。 相似文献
7.
David P. Bacon Nash’at N. Ahmad Thomas J. Dunn Michael C. Monteith Ananthakrishna Sarma 《Natural Hazards》2008,44(3):317-327
By definition, a crisis is a situation that requires assistance to be managed. Hence, response to a crisis involves the merging
of local and non-local emergency response personnel. In this situation, it is critical that each participant: (1) know the
roles and responsibilities of each of the other participants; (2) know the capabilities of each of the participants; and (3)
have a common basis for action. For many types of natural disasters, this entails having a common operational picture of the unfolding events, including detailed information on the weather, both current and forecasted, that may impact on either
the emergency itself or on response activities. The Consequences Assessment Tool Set (CATS) is a comprehensive package of
hazard prediction models and casualty and damage assessment tools that provides a linkage between a modeled or observed effect
and the attendant consequences for populations, infrastructure, and resources, and, hence, provides the common operational
picture for emergency response. The Operational Multiscale Environment model with Grid Adaptivity (OMEGA) is an atmospheric
simulation system that links the latest methods in computational fluid dynamics and high-resolution gridding technologies
with numerical weather prediction to provide specific weather analysis and forecast capability that can be merged into the
geographic information system framework of CATS. This paper documents the problem of emergency response as an end-to-end system
and presents the integrated CATS–OMEGA system as a prototype of such a system that has been used successfully in a number
of different situations. 相似文献
8.
Ramesh Sivanpillai X. Ben Wu R. Srinivasan Charles T. Smith Michael G. Messina 《GeoJournal》2008,71(4):211-220
Comparing satellite data derived map products are affected by differences in data characteristics, image acquisition dates,
processing techniques, and classification schemes used for assigning pixels to a thematic class. By comparing two forest maps
generated from Landsat Enhanced Thematic Mapper Plus (ETM+) and Advanced Very High Resolution Radiometer (AVHRR) images acquired
on the same day, and processed using identical classification scheme and methods these differences were minimized. The ETM+
derived map had higher classification accuracy values and more precise area estimates than the AVHRR derived map. In the ETM+
derived map, 87 of the 599 verification data were misclassified, whereas in the AVHRR derived map, 155 of the 469 verification
data were misclassified. Detailed error analyses by land cover class revealed that a land use based definition of forest accounted
for 74% (64 out of 87) and 57% (89 out of 155) of the classification errors in ETM+ and AVHRR derived maps, respectively. 相似文献
9.
10.