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891.
遗传算法作为一种智能优化算法,已广泛应用许多学科及工程领域.本文提出了利用遗传算法对遥感影像增强进行空域操作,设计中构造了一种简单且规一化亮度变换函数,并设计遗传算法实现影像的自适应增强.实验结果表明,该算法处理后质量比传统算法要好. 相似文献
892.
894.
遥感技术在工程地质选址工作中的应用 总被引:1,自引:0,他引:1
通过遥感工程地质选址工作的系统分析,总结了区域地形地貌条件、岩土体条件、地质构造条件、地质灾害发育情况和水文
地质条件等工程地质条件的研究内容和工作方法,指出了遥感工程地质选址工作中应注意的问题。 相似文献
895.
利用多期遥感数据,对浙江省东部象山港一带近30 a来的海岸线及潮滩变迁状况进行了调查与监测。结果表明,该区淤泥质海滩发育,海岸类型以淤泥质为主,岸线在1986~1996年间有较大变化,外迁宽度最大达1 700 m,1996年以后基本进入稳定状态。潮滩发育具有差异性。 相似文献
896.
In many geoscientific applications, one needs to recover the quantities of interest from indirect observations blurred by
colored noise. Such quantities often correspond to the values of bounded linear functionals acting on the solution of some
observation equation. For example, various quantities are derived from harmonic coefficients of the Earth’s gravity potential.
Each such coefficient is the value of the corresponding linear functional. The goal of this paper is to discuss new means
to use information about the noise covariance structure, which allows order-optimal estimation of the functionals of interest
and does not involve a covariance operator directly in the estimation process. It is done on the basis of a balancing principle
for the choice of the regularization parameter, which is new in geoscientific applications. A number of tests demonstrate
its applicability. In particular, we could find appropriate regularization parameters by knowing a small part of the gravitational
field on the Earth’s surface with high precision and reconstructing the rest globally by downward continuation from satellite
data. 相似文献
897.
Amongst many ongoing initiatives to preserve biodiversity, the Millennium Ecosystem Assessment again shows the importance to slow down the loss of biological diversity. However, there is still a gap in the overview of global patterns of species distributions. This paper reviews how remote sensing has been used to assess terrestrial faunal diversity, with emphasis on proxies and methodologies, while exploring prospective challenges for the conservation and sustainable use of biodiversity. We grouped and discussed papers dealing with the faunal taxa mammals, birds, reptiles, amphibians, and invertebrates into five classes of surrogates of animal diversity: (1) habitat suitability, (2) photosynthetic productivity, (3) multi-temporal patterns, (4) structural properties of habitat, and (5) forage quality. It is concluded that the most promising approach for the assessment, monitoring, prediction, and conservation of faunal diversity appears to be the synergy of remote sensing products and auxiliary data with ecological biodiversity models, and a subsequent validation of the results using traditional observation techniques. 相似文献
898.
In the study of the application of MODIS satellite remote sensing data to earthquake prediction, the paper puts forward for the first time a quantitative method to estimate the ratio for the pixels with abnormal brightness temperature (BT) increase and a preliminary scheme for cloud removal. The principle is that, firstly, the cloudless data observed by the same satellite at the same period of time but in different days (usually 1 day to 3 days) are mosaiced to get high ratio of clear sky, and then the BT variation curve and mean square difference (MSD) of each pixel are calculated with the data from the covered area to determine daily whether the BT data of the day is normal or not at a certain pixel by using double the MSD as the criterion. The ratio for the pixels with abnormal BT increase can be calculated by dividing the total number of abnormal pixels with the total pixels of the whole area. Analysis on a series of recent earthquakes in the Taiwan area shows that the ratio for pixels with abnormal BT increase, which normally undulates around zero, has a sudden enhancement 1 day to 20 days before medium-strong earthquakes. It is expected that a new method for identifying earthquake auspice could be found through special studies in regions with frequent seismic activity by analyzing the change of the ratio for the pixels with abnormal BT increase from MODIS satellite remote sensing infrared (IR) information from which the effect of clouds has been removed to a certain extent. 相似文献
899.
900.
Hurricanes produce mixing and flow divergences (and convergences) that alter the upper-ocean heat content (OHC), which in turn affects the storm. Ocean observations under a hurricane are rare, making it difficult to validate forecast models. Past research have mainly focused on OHC-changes by vertical mixing and tacitly assumed that horizontal transports are slowly varying. Moreover, effects of coastal boundaries on ocean responses to hurricanes are generally omitted. This work uses satellite data to detect and verify forecast isopycnal motions under hurricane Wilma (Oct/16–26/2005) in the Caribbean Sea and the Gulf of Mexico. The model is then used to show that Wilma-induced convergences in northwestern Caribbean Sea produce increased Yucatan-Channel transport into the Gulf ahead of the storm, and the Yucatan–Loop Current front diverts most of this heat around the Loop. This response is distinct from that of an ocean without the Loop, for which warming is widespread north of the channel. These intricate ocean responses can impact hurricane predictions. 相似文献