How to Update a DEM with Survey Data?

In most of the times the Analyst identify the data inadequacy for caring out the task. In that time analyst need to update existing database with newly collected data. 

In irrigation and water supply development projects needs DEM, in such cases, Update the DEM with new survey data is Important.

How to face this Challenge?

We  have 

1. Existing DEM (Most properly in *.img format)

2. Survey Data (XYZ data, in Excel sheet)

Workflow:

1. We need to be open ArcMap, and add these two data.

2. Convert Point data into Shape file 

(Use Display XY data)

3. Define the Interest area 

(Create new polygon layer and draw a polygon where the Survey Data available )

4. Develop TIN layer 

( 3D analyst toolbox  Data Management > TIN > Create TIN )

5. Convert TIN to Raster

 ( Conversion > From TIN > TIN to Raster )

6. Clip Raster using Area of Interest Polygon 

( Data Management > Raster > Raster Processing > Clip)

Note: Make sure the Check box of "Use input features for Clipping Geometry 

7. Update Existing Raster DEM using Newly Created Raster 

( Data Management > Raster > Raster Dataset > Mosaic to new Raster )

Note: 

Input Raster : Newly Created Raster, Existing DEM ( Keep order)

Output Location : Specify as your request

Raster Dataset Name with Extension : Specify as your wish but do not forget to add extension (Ex. Updatedem.img) (*.img is recommend for open dataset in different applications)

Pixel Type : If your Survey Elevations have Negative values then use signed, otherwise maintain your existing DEM pixel type.

Mosaic Operator : First (If your order is other-way round, keep last)

8. Click OK, your DEM is updated!!

 

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STUDY OF SUITABLE METHODS OF BUILDING EXTRACTION FROM HIGH-RESOLUTION SATELLITE IMAGERIES– CASE STUDY OF JAFFNA, SRI LANKA.

The Location of each building is a necessary data for planning of disaster, resource management, infrastructure development, service providing etc. Traditionally, the building boundaries are delineated through manual digitization from digital images in stereo view using the photogrammetric stereo plotters. However, this process is a tiresome and time consuming task and requires qualified people and expensive equipment. For this reason, building extraction using the automatic techniques has a great potential and importance. In developed countries automatic building extraction is being increasingly used for urban planning and management. Therefore, it has been the focus of intensive research for the last decade.

When comparing with other convenient method of Survey, the satellite imagery is cost and time effective. However, in Sri Lanka not enough research in this content and still no organization has considered this technology.

Several case studies carried out in other countries in urban area building extraction. In most of the developed countries urban building have some similar characteristics such as built materials, shape and texture. But in Sri Lankan rural context is completely different in the aspects of building materials, different shape of buildings and no any patterns. All of above the canopy cover is the great challenge.

Due to these differences Sri Lanka requires a specific research to identify the proper algorithm and implementation mechanism for time and cost effective building location data collection from high resolution multi spectral satellite imagery.

Full Research Report Download Here

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eCognition Developer 9.01 x64 - Fully Cracked

eCognition is the original object-based image analysis software.First launched in May 2000, eCognition introduced the computer method for extracting information from images using a hierarchy of image objects (groups of pixels) as opposed to traditional pixel processing methods.

Instruction for Installing

1. Extract and install the software with 'set license later'

2. Overwrite patch folder

Patch and Software Download Here

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Arcmap 10.3 - Crack and Desktop Full Download

ArcGIS 10.3 introduces several new products. Portal for ArcGIS is now a core product that you deploy on your internal network to share maps, applications, and other geographic information with other members of your organization.
It enables the capabilities of ArcGIS Online behind your organization's firewall. With the introduction of a new extension to ArcGIS for Server called ArcGIS GeoEvent Processor, organizations can process extensive real-time data on the fly and display relevant information from these feeds in ArcGIS clients.

Download

installation Guide

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Editing in ArcGIS Desktop 10

The improved editing environment in ArcGIS Desktop 10 features a reorganized editing interface that offers easier access to tools. This course introduces new streamlined editing workflows, which provide a more intuitive experience and allow for quicker completion of data editing tasks.

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Automated Volume Calculation from Spot Elevation Point Data

So many GIS and Engineering Design Software facilitating Volume Calculation

 include Open and Free Source Software also. However Most of that user should follow some steps of Mouse Clicks then its need User interaction. But when you try to Make automated using Sever and Client its Can not help you. that time you want to write up a sophisticated code block for that part. Its time consuming and Error prone also.

In this Place the SAGA GIS will Help you. its an Open Source Software from SourceFrog. Further its a command prompt software. So we can Write up our Steps in a *.bat file and Execute that on Sever through php Code block.  

The Sample command Prompt Code for Volume Calculation:

@ECHO OFF

REM SET SAGA_MLB=C:\SAGA\Modules

REM SET PATH=%PATH%;C:\SAGA

REM Tool: Convert Table to Points

saga_cmd shapes_points 0 -POINTS= -TABLE=path for input point *.txt file -X=0 -Y=1 -Z=2 -POINTS=C:\SAGA\output.shp path for output *.shp file

@ECHO OFF

REM Tool: Triangulation

saga_cmd grid_gridding 5 -SHAPES=C:\SAGA\output.shp -FIELD=2 -TARGET_DEFINITION=0 -TARGET_USER_XMIN=X minimum of Dataset -TARGET_USER_XMAX=X maximum of Dataset -TARGET_USER_YMIN= Y minimum of Dataset -TARGET_USER_YMAX=Y maximum of Dataset -TARGET_USER_SIZE=0.5 -TARGET_USER_FITS=0 -TARGET_OUT_GRID=C:\SAGA\output.sgrd

REM Tool: Grid Volume

saga_cmd grid_calculus 2 -GRID=C:\SAGA\output.sgrd  -METHOD=0 -LEVEL=0.000000



Further Details you can Refer
http://saga-gis.org/en/index.html

This is an example application of SAGA GIS it can be Used for several Automated GIS Applications.

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How to populate Random Numbers in a field in ArcMap

Most of the time we are struggling to get random values in Arcmap Attribute table field. But its very simple with use of VB Script.

1. Add a Integer Field on your relevant attribute table and name it RandomValue.

2. Right Click on it and Select the Field Calculator

3. Select the Parser as VBScript

4. Ensure the Show Codeblock checkbox is ticked.

5. Paste the Following Code in Pre Logic Script Code text box;
                           dim max, min
           max=20
           min=5
           x=(Int((max-min+1)*Rnd+min))

In the equation above, max=20 and min=5 sets the maximum and minimum values that will be created in the field. No values will be  randomly created below 5 or above 20. If you want Change as your wish

6. Type in RandomValue text box
                  x

7. Click the Ok Button. You have done.


If you did not like to use VBScript you can Use the python also.

Pre-Logic Code for Python is

                               def fillRandomInt(intMin, intMax):
             import random
             return random.randint(int(intMin),int(intMax))

RandomValue=
                               fillRandomInt(1946,2010)


Here I made the limits are 1946 to 2010, You can change it according to your requirement.

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