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Michael Fuchs Adnan A. Awan Sardar S. Akhtar Ijaz Ahmad Simon Sadiq Asif Razzak Naghmah Haider 《山地科学学报》2017,14(5):948-963
In the frame of landslide susceptibility assessment, a spectral library was created to support the identification of materials confined to a particular region using remote sensing images. This library, called Pakistan spectral library (pklib) version 0.1, contains the analysis data of sixty rock samples taken in the Balakot region in Northern Pakistan. The spectral library is implemented as SQLite database. Structure and naming are inspired by the convention system of the ASTER Spectral Library. Usability, application and benefit of the pklib were evaluated and depicted taking two approaches, the multivariate and the spectral based. The spectral information were used to create indices. The indices were applied to Landsat and ASTER data to support the spatial delineation of outcropping rock sequences in stratigraphic formations. The application of the indices introduced in this paper helps to identify spots where specific lithological characteristics occur. Especially in areas with sparse or missing detailed geological mapping, the spectral discrimination via remote sensing data can speed up the survey. The library can be used not only to support the improvement of factor maps for landslide susceptibility analysis, but also to provide a geoscientific basis to further analyze the lithological spot in numerous regions in the Hindu Kush. 相似文献
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The electrostatic shocks and solitons are studied in weakly relativistic and collisional electron-positron-ion plasmas occurring
in polar regions of pulsar. The plasma system is composed of relativistically streaming electrons, positrons while ions are
taken to be stationary. Dissipative effects in the system are due to collision phenomena among the constituents of relativistic
plasma. Nonlinear dynamics of the dissipation and dispersion dominated relativistic plasma systems are governed by Korteweg-de
Vries Burger (KdVB) and Korteweg-de Vries (KdV) equations respectively. Numerical results, exploring the effects of plasma
parameters on the profile of nonlinear waves are expedited graphically for illustration. Positron to electron temperature
ratio plays the role of a decisive parameter. It is noticed that compressive shocks and solitons evolve in the system if the
positron to electron temperature ratio is less than a critical value. However, there exists a threshold value of positron
to electron temperature ratio beyond which the system supports the rarefactive shocks and solitons. The results may have importance
in the relativistic plasmas of pulsar magnetosphere. 相似文献