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Geospatial Analysis - spatial and GIS analysis techniques and GIS software

Geospatial Analysis - spatial and GIS analysis techniques and GIS software
Related:  RS and GIS

The Open Source Analysis of Competing Hypotheses Project Multicriteria analysis to study erosion risk using ArcGIS Today we are going to study the erosion risk of a terrain. With multicriteria analysis we are going to analyse the slope as well as its proximity to rivers. We will follow these 3 steps: 1. 2. 3. 1. We need a DTM raster layer. First of all we are going to use the Slope tool: Spatial Analyst Tools > Surface > Slope Now, the problem is that we have data in a different scale. Therefore we will reclassify it in 4 degrees according to its gradient, being the highest number the one of biggest inclination. Spatial Analyst Tools > Reclass > Reclassify First, click Classify in order to fix the classes and define the break values. Click OK and you return to the previous window where we will value the areas with highest inclination with a bigger number. 2. We need to obtain the river basins. Spatial Analyst Tools > Hidrology > Flow accumulation Next, with the generated raster we select: TRICK: Going back to classify inside reclassify, we can observe the graphic and find the accumulation value of the river.

Software articles some semi-formal writings on a limited range of subjects Software development Software Architecture For A New Economic System A rough, high-level software description for a general economic system: an informational structure/means for organising cooperation. (Or an 'engineering fiction'.) (2000 words, 15 min read) Tractatus Computo-Philosophicus A brief philosophical expression of software development, in the style of Wittgenstein's Tractatus. (550 words, 5 min read) Understanding Software Engineering Design A brief description of what seem to be the abstract essentials of software engineering design. (3000 words, 20 min read) On Naur's ‘Programming As Theory Building’ A problem in Naur's ‘Programming As Theory Building’ and the improved philosophical model it prompted. (1500 words, 10 min read) Is 'Software Architecture' Really Architecture ? The software world doesn't know what ‘architecture’ means. A Building Industry Model For Software Development Software Architecture And Engineering Definitions

Download Free RADARSAT Data of Canada - GIS Resources Canada’s RADARSAT-1 is a radar satellite and was launched in November 1995. It carries a Synthetic Aperture Radar (SAR), it acquired images of the Earth day or night, in all weather and through cloud cover, smoke and haze. RADARSAT-1 was a Canadian-led project involving the Canadian federal government, the Canadian provinces, the United States, and the private sector. It provided useful information to both commercial and scientific users in such fields as disaster management, interferometry, agriculture, cartography, hydrology, forestry, oceanography, ice studies and coastal monitoring. RADARSAT orthorectified mosaic image of Canada The Government of Canada provides free access to RADARSAT through the website “Natural Resources Canada”. The ortho-rectified mosaic of Canada RADARSAT data is available via FTP (file transfer protocol) server of Natural Resources Canada. Download Data from FTP Server: RADARSAT orthorectified mosaic data of Canadian province (100m).

Collaborative storytelling The Advantages of a UAV - LiDAR News Mobile laser scanning and airborne laser scanning point clouds come with their unique advantages and disadvantages. Mobile laser scanners cannot acquire data from building rooftops and the airborne laser scanners cannot acquire data from building facades because of their view angles. Therefore the point cloud measurements from any of these two scanners have areas which do not have enough points to represent the 3D structures properly. One solution to increase the density of point clouds is to use UAV cameras. Tony Nedkov has used a UAV camera in order to generate point cloud of a specific building. To do so, Tony has applied Structure from Motion (SfM) techniques to the acquired video. Primary steps of his work can be seen in the following images and in the video provided with the link below. Thanks to Beril Sirmacek for this post.

Smartsheet and Google Apps: Crowdsourcing Made Easy - ReadWriteEnterprise Let's say you want a list of every Fortune 1,000 CEO in the United States, along with a picture and contact information. You can look through Google. Top page results may help a bit. Crowdsourcing works but you need a process and a way to organize the information. Smartsheet provides a way to use wikis and spreadsheets for crowdsourcing information from services like Mechanical Turk and Live Works. Smartsheet recently integrated with Google Apps. Let's say you have a list of the startup companies from the top 10 metro areas in the United States. You may now make your request to have the work done for you. You can then import the spreadsheet back into Google Apps. Smartsheet integrates with a wiki environment. Crowdsourcing is a classic example of how the enterprise can get information almost immediately that could take hours to collect if done manually by one person. The cost savings alone makes Smartsheet an application worth giving a try. SmartSheet is a subscription service.

How to convert Landsat DNs to Brightness Temperature using ENVI Standard | Center for Earth Observation The Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper Plus (ETM+) sensors acquire Thermal InfraRed (TIR) data and store this information as a digital number (DN) with a range between 0 and 255. The Landsat 8 OLI sensor stores these data as DNS with a range from 0 to 65536. ENVI Standard can easily convert these DNs to degrees Kelvin. You need to open the original USGS supplied file in USGS GeoTIFF with Metatdata format. Open the file that ends with “_MTL.TXT”. ENVI will automatically open the Landsat image as multiple files. Using ENVI Standard, select from the Toolbox | Radiometric Correction | Radiometric Calibration.

Crowdsource Is Not Open Source Subscribe to this blog About Author With a focus on open source and digital rights, Simon is a director of the UK's Open Rights Group and president of the Open Source Initiative. He is also managing director of UK consulting firm Meshed Insights Ltd. Contact Author Email Simon Twitter Profile Google+ Profile Linked-in Profile I've heard a few conversations in the last week treating open source interchangeably with crowdsourcing. Open source describes a pragmatic projection of the four software freedoms - to use, study, modify and distribute software for any purpose. Crowdsourcing describes the leveraging of the marginal interest and free time of a large group of people to complete a task that otherwise could not be economically completed. The new US web phenomenon Kickstarter is a modern example of crowdsourcing. This is not to say I think crowdsourcing in general is a bad thing.

Understanding Landsat 8 | Land Surface Properties, Regional Climate Feedbacks and Urban Adaptations Home > Landsat 8 Understanding Landsat 8 In order to better understand and analyze the new Landsat 8 satellite images for environmental monitoring, the Yale Center for Earth Observation is conducting an in-depth analysis into various highlights and shortcomings one should be aware of when handling these satellite images. Reflectance Bands Calibration Error - Cirrus Negative Reflectance Values Greater than 1 Reflectance Values Landsat 8: Comparison of TOA Reflectance with SP3 Albedo Landsat 5: Radiance/Reflectance Calculation Comparison Landsat 8: Comparison of TOA Radiance with SP3 Cirrus Band Coastal Aerosol Band Striping: Summary of Sensor Calibration Error Thermal Bands Calibration Error - TIR Masking Border Pixels Bands 10 and 11 Temperature Comparisons Temperature and Radiance - SP3 vs. Emissivity - SP3 vs. Temporal Comparison: Dominica Full Image Temporal Comparison: Dominica ROI Dominica ROI Statistics

When judging visualizations, intent matters The field of data visualization all too often is viewed as having the single role of attaching data to an image, regardless of whether it’s for analysis or journalism or entertainment. In a recent interview, Ben Fry, principal at Fathom, said this is a tendency that needs to be overcome. Visualizations have far more nuance, and varied intent, than many people realize: People evaluate stuff that’s, say, for journalism or for pure entertainment under the same rubric as the way that you look at analytic tools. We need different ways of evaluating things. Fry compared visualization to the field of writing, in which the roles of various genres and outcomes — and how they are perceived and consumed — are more clearly defined. We’re going to start understanding that visualization isn’t this sort of monolithic thing — that it’s not “data plus image equals this.” Related: