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141.
I.Intr0ducti0nAwnerresource-environmentalsystem,withmanyquantitativeandqualitativefactors,consistsofwaterresourcesdevelopmentandenvironment.Itisveryddriculttocarryoutoverallassessmentsanddecision-maldngstudiesofthesystemusingapurelyquantitativen1athematical-l11odel.However,AnalyticalHicerarcl1yProcess(AHP,anewmethodfOrtheplanninganddecisioll-making,combiningqualitativefactorswithquantitativefactors,cansolvethedecision-mdengpr0blemsOfmultiplehierarchiesandgOalsforacomplexsystem.Thismeth0d,t… 相似文献
142.
James S. Gardner 《地球表面变化过程与地形》1983,8(4):347-355
Accretion of debris was monitored on six slopes in the Mt. Rae area of the Canadian Rocky Mountains for the period 1975–1982. Monitoring was accomplished by measuring annually the accumulated debris on fabric mats which were placed on the long profile of the slopes. Annual rates of accretion were extremely variable between points on the same slope, between slopes, and between years. The data do not show a systematic decrease in accretion downslope but indicate that an absence of accretion is more likely on the lower half of the slopes. In general, annual rates are comparable to previously published values from the Rockies and the maximum rates of 30 to 40 mm per year are comparable to those from Karkevagge in Scandinavia. Extremely high rates of accretion were all related to extreme events such as debris flows or full depth snow avalanches. The variation in accretion rates is not explained by single environmental factors such as lithology and slope exposure. 相似文献
143.
A two-way nested-grid ocean-circulation model for the Meso-American Barrier Reef System 总被引:2,自引:0,他引:2
A two-way nested-grid ocean-circulation model is developed for the Meso-American Barrier Reef System (MBRS), using a newly developed two-way interactive nesting technique. The unique feature of this new nesting technique is its use of the semi-prognostic method (Sheng et al. 2001) to exchange information between different grids through the model momentum equations. The nested-grid model for the MBRS has a fine-resolution inner model embedded in a coarse-resolution outer model. The outer model is the western Caribbean Sea model developed by Sheng and Tang (2003), with a horizontal resolution of roughly 19 km. The inner model domain covers the northwest Caribbean Sea (NWCS) between 79°W and 89°W and between 15.5°N and 22°N, with a horizontal resolution of roughly 6 km. The nested-grid ocean model is initialized with the January mean temperature and salinity and forced by the monthly mean COADS (comprehensive ocean-atmosphere data set) wind stress and surface heat flux. The model sea-surface salinity is restored to the monthly mean climatology. The nested-grid model is integrated for 2 years and the second-year model results are presented in this paper. The model-calculated annual-mean near-surface currents over the NWCS agree reasonably well with the time-mean near-surface currents inferred by Fratantoni (2001) from trajectories of the satellite-tracked 15-m drogued drifters in the 1990s. The two-way nested model is also used to quantify the role of local wind stress, local density gradients and boundary forcings of the outer model in driving the annual-mean circulation in the region.Responsible Editor: Phil Dyke 相似文献
144.
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146.
论地质信息科学 总被引:7,自引:4,他引:7
地质信息科学是关于地质信息本质特征及其运动规律和应用方法的一个综合性学科领域.其发生和发展,是地球信息科学与地质科学相结合的产物,内部条件是地质学定量化和地矿勘查信息化的自身需要,外部条件是计算机科学和地球空间信息科学兴起和发展的促进.其研究对象是岩石圈的地质信息,其理论框架的核心是地质信息机理,包括地质信息的本质、运动规律、传输机制和信息流的形成机理等.其方法论体系包含着主题信息管理法、信息分析综合法、行为功能模拟法和系统整体优化法.其技术体系由地质数据采集、地质数据管理、地质数据处理、地质图件编绘、地质过程模拟、地质资源评价、地质信息传播及其多S集成化技术所组成. 相似文献
147.
A landslide susceptibility model using the Analytical Hierarchy Process method and multivariate statistics in perialpine Slovenia 总被引:27,自引:3,他引:27
Landslides cause damage to property and unfortunately pose a threat even to human lives. Good landslide susceptibility, hazard, and risk models could help mitigate or even avoid the unwanted consequences resulted from such hillslope mass movements. For the purpose of landslide susceptibility assessment the study area in the central Slovenia was divided to 78 365 slope units, for which 24 statistical variables were calculated. For the land-use and vegetation data, multi-spectral high-resolution images were merged using Principal Component Analysis method and classified with an unsupervised classification. Using multivariate statistical analysis (factor analysis), the interactions between factors and landslide distribution were tested, and the importance of individual factors for landslide occurrence was defined. The results show that the slope, the lithology, the terrain roughness, and the cover type play important roles in landslide susceptibility. The importance of other spatial factors varies depending on the landslide type. Based on the statistical results several landslide susceptibility models were developed using the Analytical Hierarchy Process method. These models gave very different results, with a prediction error ranging from 4.3% to 73%. As a final result of the research, the weights of important spatial factors from the best models were derived with the AHP method. Using probability measures, potentially hazardous areas were located in relation to population and road distribution, and hazard classes were assessed. 相似文献
148.
149.
Stephen V. Stehman 《Journal of Geographical Systems》2006,8(2):209-226
Assessing thematic map accuracy is a special type of map comparison that is frequently applied to remote sensing classification problems. For map comparisons in the accuracy assessment setting, one map represents the classified output and the other map represents the true or “reference” condition. Several articles in this special issue describe state-of-the-art map comparison analysis tools that could serve to quantify accuracy of a single map. However, accuracy assessment objectives generally extend beyond describing accuracy of a single map to comparing accuracy of several maps. Consequently, interest focuses on comparing map comparison measures when these measures are used to represent accuracy. The virtual workshop emphasizes the analysis component of map comparisons, but it is also important to examine the underlying study designs generating the data input into these analyses. The study designs for accuracy comparisons implemented in remote sensing practice often investigate only a single test site, thus limiting our ability to generalize the results of these accuracy comparisons. Map accuracy comparison studies can be designed to provide stronger generalizations by incorporating experimental design principles such as replication and blocking, and identifying an experimental unit appropriate for the application. It is also important to recognize the role of statistical hypothesis testing and inference for different objectives that motivate map accuracy comparisons. Deciding which of two maps to use for a particular site can be addressed by enumerative inference and does not require hypothesis testing. For the objective of a more general comparison of classification procedures, analytic inference is appropriate and hypothesis testing plays a more prominent role. 相似文献
150.
介绍了江西省数字化雷达回波拼图的技术方法。该方法主要包括回波资料的预处理、拼图投影处理。它具有资料同一性、准确性好、方便灵活、适合业务使用等特点。 相似文献