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How to predict time dependent variables with the help of neural networks ?

Objective: To predict the probability of rainfall based on monthly mean data of rainfall, runoff and evapotranspiration collected from a single gauge station for the last fifty years Data Preprocessing : The fifty years mean monthly data of Rainfall,Runoff and Evapotranspiration is available.The data values of the variables is ranked in a descending way where best or minimum rank is assigned to the largest value and worst or maximum rank was given to smallest value of the variable.The probability of each of the data value of the variables can be calculated with the help of the following formula : P = m/(n+1) The data thus converted become dimensionless and thus normalization is not followed. If the data values have dimensions it is better to remove the scale from the same. This will make the job of the neural network program faster and easier. Input Variables of the Present Study : Input to the model will be Probability of Runoff and Evapotranspiration. Output Variable of the Present S...

Introduction to GIS Coordinate Systems

The position of a point in a 2D or 3D surface is defined by a system of coordinates.There are mainly three types of Coordinate Systems that you can use to represent the position of the point : 1.Geographic Coordinate System(GCS) : In this type of systems Latitutde and Longitude are used to represent the position of a point in a 3D surface.The surface (like sphere or spheroid or ellipsoid) which mimics the real shape of the World(referred as Geoid) is also known as Reference Surface.The real surface of the earth is very hard to predict due to its undulations and thus represented by a form of common shapes like spheroids or ellipsoids. 2.Projected Coordinate Systems(PCS) : The Projected Cordinate Systems are a system to represent the positions of a point in a 2d surface projected from the GCS by intersecting or tangentially wrapping the referance 3d surface.The Coordinates are represented by x and y which respectively represents the longitude and latitutde of the GCS. 3.Custom Coordinat...