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Spatial filtering, Remote Sensing. Low-pass filter. High-pass filter

Spatial filtering encompasses another set of digital processing functions which are used to enhance the appearance of an image. Spatial filters are designed to highlight or suppress specific features in an image based on their spatial frequency. Spatial frequency is related to the concept of image texture. It refers to the frequency of the variations in tone that appear in an image. "Rough" textured areas of an image, where the changes in tone are abrupt over a small area, have high spatial frequencies, while "smooth" areas with little variation in tone over several pixels, have low spatial frequencies. A common filtering procedure involves moving a 'window' of a few pixels in dimension (e.g. 3x3, 5x5, etc.) over each pixel in the image, applying a mathematical calculation using the pixel values under that window, and replacing the central pixel with the new value. The window is moved along in both the row and column dimensions one pixel at a time and the ca

Grey level thresholding. Level slicing. Contrast stretching lo p

Grey level thresholding. Level slicing. Contrast stretching. Image enhancement Lillesand and Kiefer (1994) explained the goal of image enhancement procedures is to improve the visual interpretability of any image by increasing the apparent distinction between the features in the scene. This objective is to create "new" image from the original image in order to increase the amount of information that can be visually interpreted from the data. Enhancement operations are normally applied to image data after the appropriate restoration procedures have been performed. Noise removal, in particular, is an important precursor to most enhancements. In this study, typical image enhancement techniques are as follows: Grey level thresholding Grey level thresholding is a simple lookup table, which partitions the gray levels in an image into one or two categories - those below a user-selected threshold and those above. Thresholding is one of many methods for creating a binary mask for an i

Aquifer. Types of Aquifer.

What is an Aquifer? An aquifer is a body of saturated rock through which water can easily move. Aquifers must be both permeable and porous and include such rock types as sandstone, conglomerate, fractured limestone and unconsolidated sand and gravel. Fractured volcanic rocks such as columnar basalts also make good aquifers. The rubble zones between volcanic flows are generally both porous and permeable and make excellent aquifers. In order for a well to be productive, it must be drilled into an aquifer. Rocks such as granite and schist are generally poor aquifers because they have a very low porosity. However, if these rocks are highly fractured, they make good aquifers. A well is a hole drilled into the ground to penetrate an aquifer. Normally such water must be pumped to the surface. If water is pumped from a well faster than it is replenished, the water table is lowered and the well may go dry. When water is pumped from a well, the water table is generally lowered into a cone of dep

Remote Sensing Multi & Hyperspectral Systems

<iframe style='width:900px;height:500px' src=' https://online.pubhtml5.com/fjpl/pxsm/ '  seamless='seamless' scrolling='no' frameborder='0' allowtransparency='true' allowfullscreen='true' ></iframe> https://online.pubhtml5.com/fjpl/pxsm/ Satellite Remote Sensing; Multispectral imaging; Using Discrete Detectors and Scanning mirrors- Landsat- MMS, TM, ETM+; NOAA- GOES, NOAA-AVHRR; SeaWiFS Multispectral imaging Using Linear Arrays; SPOT 1, 2, 3 HRV, SPOT 4, 5 HRVIR; IRS- LISS III and LISS IV; ASTER; Quick Bird Imaging Spectrometry using Linear and Area Arrays; AVIRIS, MODIS  Vineesh V AISHE and UGC Nodal Officer Assistant Professor of Geography, Government College Chittur, Palakkad https://vineesh-geography.business.site

Folding is a concept that embraces all geologic processes by which surfaces in rocks become curved during deformation

Folding is a concept that embraces all geologic processes by which surfaces in rocks become curved during deformation. Since folds are permanent deformation structures with no or little loss of cohesion of the folded layer, folding refers to the essentially slow, ductile behaviour of relatively soft and/or hot rocks. Beyond the descriptive, anatomical classifications, much of the early geologic work on folding processes focused on the deformation of stratified sediments. Different folding mechanisms combine a few basic processes involving the geometrical (layer thickness and spacing) and physical (viscosity, viscosity contrast, anisotropy) properties of the rocks. This lecture deals with some consideration on genetic, mechanical aspects concerning the development of folds. The important point to note is that stress alone is insufficient to cause folding: A planar surface must first exist to define the fold shape, and the orientation of this planar marker with respect to the stress dir

Internship @ National crop forecast Centre. #GIS Remote Sensing #Geography.

#Internship @ National crop forecast Centre. #GIS Remote Sensing #Geography. The internship programme will provide an opportunity for the officers of the MNCFC to interact with young thinking minds with brilliant academic record from reputed institutions. Ideas from budding scholars will prove to be of importance to the practitioners of Remote Sensing in the MNCFC. At the same time, the internship programme will also provide the interns with an excellent opportunity to familiarize themselves with the applications of Remote Sensing (RS) and GIS in Agricultural Assessment. (b) The interns may benefit by getting exposure to advanced RS & GIS Data Analysis and Forecasting Data analysis procedures at MNCFC and contribute to development of techniques for improving agriculture assessment.  (c) MNCFC may benefit from the additional resources in the form of young talent and their new ideas may add to MNCFC forecasts.  Vineesh V AISHE and UGC Nodal Officer Assistant Professor of Geography, G

M.Sc Geoinformatics. Forensic University

Admission opens at World's first Forensic university!!!  School of Earth, Space, and internet technologies invites application for two years M.Sc Geoinformatics program!  Students will get chance to apply and innovate #geoinformatics tools for national security!

Poverty Mapping and Poverty Index.

http://dx.doi.org/10.13140/RG.2.2.36657.66403 MPI. Multidimensional Poverty Index of Tamilnadu. Spatial Pattern of poverty, a GIS based Mapping and analysis. DOI: 10.13140/RG.2.2.36657.66403 🌐

Piqiang Fault

Satellite image of the Piqiang Fault, a northwest trending left-lateral strike-slip fault in the Taklamakan Desert south of the Tian Shan Mountains, China (40.3°N, 77.7°E). (credit: NASA Earth Observatory images)

Application of GIS in Poverty mapping

https://www.researchgate.net/publication/359648954_Multidimensional_Poverty_Index_KarnatakaTamil_Ndau_and_Kerala_GIS Multidimensional Poverty Index. Karnataka,Tamil Ndau and Kerala. DOI:10.13140/RG.2.2.36431.56486 Application of GIS in Poverty mapping .