DEM/DTM Generation

Digital Elevation Model is the representation of earth’s topography using digital methods. Digital elevation model is also called as digital terrain model (DTM). DEMs or DTMs can be represented as original maps, square grids or irregular network of triangles.
The main application of DEM are,

• GIS Services
• Surface Analysis
• Orthophoto generation
• Global Positioning System
• Aerial Photography
• Bare Earth Surface Model
• Base Mapping
• 3D Visualization

To get more information check this link DEM/DTM generation

Georeferenced data processing services

To georeference something means to define its existence in physical space,which means establishing its location in terms of map projections or coordinate systems. The term is used both when establishing the relation between raster or vector images and coordinates but also when determining the spatial location of other geographical features. Examples would include establishing the correct position of an aerial photograph within a map or finding the geographical coordinates of a place name or street address. This procedure is thus imperative to data modeling in the field of geographic information systems (GIS) and other cartographic methods.These can be done by georeferenced data processing service providers. When data from different sources need to be combined and then used in a GIS application, it becomes essential to have a common referencing system. This is brought about by using various georeferencing techniques. Most georeferencing tasks are undertaken either because the user wants to produce a new map or because they want to link two or more different datasets together by virtue of the fact that they relate to the same geographic locations.

reference: wikipedia

Latest GIS technology Concepts

We all knows about GIS , ie Geographic information system. Simply we can describe as Geographical Information System is any system that captures, stores, analyzes, manages, and presents data that is linked to location. When we consider GIS technically we can explain as, it is a system that includes mapping software and its application to photogrammetry, remote sensing, land surveying, aerial photography and photogrammetry, mathematics,mapping, geography, and tools that can be implemented with GIS software. Still, many refer to "Geographic Information System" as "GIS" even though it doesn't cover all tools connected to topology.We can also consider GIS as the merging of cartography and database technology.

Let us check various trends and applications in GIS Technology

• GIS and Science—3D analysis, graphing and data exploration, and more
•Customization and Application Development- It includes Design and Development
• Creation / Maintenance of Geo spatial Database - Design, Development and maintenance of custom geospatial databases
• Data Integration and Data Format Conversion - Also includes Spatial Analysis and Modeling
• Map Digitization / Vectorization - Digitizing maps
• Feature Extraction - 2D, 3D feature extraction using AT( aerial triangulation) results
• Ortho photography - Orthophoto Rectification and Mosaicing
• Network Analysis - Design spatial database and model features on a 3D surface for network analysis used by organizations/agencies.
• Web Mapping / Web GIS - Geodatabase Designing & Modeling, Web Mapping Automation
• Geo-Coding - Important point with mapping is registering a map with the correct real world coordinates,ie Image Georectification / Georeferencing
• GIS and CAD — Building information modeling (BIM), 3D GIS, and more
• Enterprise GIS—Extending geospatial capabilities to the enterprise
• Server GIS—Delivering geospatial services through a wide variety of clients
• Mobile GIS—Making the mobile workforce more efficient
• Cartography—Additional cartographic mapping, analysis, and editing tools
• Lidar data processing - Mapping and laser scanning

There are various many other applications in GIS technology, which can be discussed in more detail later in next article.For more details and for any queries contact http://www.sblgis.com/contact.aspx

Outsourcing GIS Services

Some of the problems facing by GIS service provider company for GIS service are competitive price, increased staff salaries, unavailability of skilled personnel, incapability to keep existing personnel, Increasing client’s demands, and dull earnings etc. All the above reasons make the companies to think about outsourcing.
Various points come into our mind while choosing a GIS outsourcing services partner .
The Key points may include
• Go through the services provided by those companies whom you are going to outsource your work.
• Analyze your needs and choose the company which can provide all your requirements.
• Go through their website deeply and understand their services thoroughly.
• Check the feedback and testimonials provided by the satisfied customers.
• Whenever you choose a company you have to check all your requirements. Otherwise you have to split up your needs to various companies which may not help to achieve cost benefits.
• The main idea behind the outsourcing is to reduce overheads and achieve cost benefits.
Some of the Outsourcing benefits are as follows
• Access to World Class Capabilities
• Cash Infusion
• Function Difficult to Manage or Out of Control
• Improve Company Focus
• Reduce Operating Costs
• Reduce Risk
• Resources not Available Internally
The GIS services may include
• Image Georectification/ georeferencing

• Geocoding
• Customization and Application Development
• Data Integration and data Format Conversion
• GIS spatial analysis services
and Modeling
• Map Digitization / Vectorization
• Enterprise GIS
• Feature Extraction
• Web mapping etc

Then finally we can choose those companies providing quality output, 24/7 customer service, capability to understand the client requirements, deadlines, technologies & needs may be considered for outsourcing.

What is Photogrammetry services?

We all knows that Photogrammetry is a remote sensing technology developed in which geometric properties about objects are determined from photographic images.
Photogrammetry is used in different fields, such as topographic mapping, architecture, engineering, manufacturing, quality control, weather forecasting, police investigation, and geology. Also it is very helpful to archaeologists to produce plans of large or complex sites and by meteorologists as a way to determine the actual wind speed of a tornado where objective weather data cannot be obtained. It is also used to combine live action with computer generated imagery in movie post-production.
Digital photogrammetry in GIS services includes Aerial triangulation,Aerial photogrammetry service, DTM DEM generation, orthophoto production and rectification, color balancing, Ortho mosaicing and tile generation, pan sharpening, contour generation, digital elevation model (DEM) extraction, 3D terain visualization, orthophotography services,geo-rectification services, photogrammetry service,Orthophoto rectification service,orthophoto generation,remote sensing services and LiDAR data processing services.

CAD services and Georeferencing

The word ‘georeferencing’ was originally used to describe the process of referencing a map image to a geographic location.

To describe it now, georeferencing is a process of taking an image and assigning geographic coordinates to it or to georeference something means to define its existence in the physical space by establishing a relation between raster or vector images to map projections or coordinate systems. When data from different sources need to be compiled and used in any GIS application, it is important to have a common referencing system. This is brought about by using various georeferencing techniques.

The process of georeferencing

Georeferencing usually refers to the method by which locations in raster and vector GIS files are related to real earth-surface positions.

Raster data is often taken by scanning maps or collecting aerial photographs and satellite images. Scanned map datasets usually do not have any spatial reference information. The location information delivered with aerial photography and satellite imagery might be inadequate and the data need not align correctly with some other data you possess.

In order to use some raster datasets in conjunction with other spatial data, you sometimes need to align or georeference them to a map coordinate system which can be defines using a map projection to display the curved surface of the earth on a flat surface.

Georeference a raster dataset means defining its location using map coordinates and assigning a coordinate system. This process allows it to be viewed, queried, and analyzed in comparison with other geographic data.

How can you georeference a raster dataset?

Add the raster dataset to be aligned to your projected data in ArcMap.

Add control points that connect known raster dataset positions to the map coordinate positions.

When the alignment becomes correct, save the georeferencing information (registration) for further use.



Though Geomatics users are familiar with the term ‘georeferening’, many of the CAD users are not much aware of the term and the use of georeferencing in CAD.


Why is it needed?

A raster image has no particular size as it is made up of pixels. The size of the vectorised CAD/GIS drawing is determined by the raster's pixel dimensions, without georeferencing. The image resolution (DPI) can determine this. This image size usually has no relationship with the size of the drawing that the raster represents.

A CAD file is usually drawn in a local coordinate system and depicts spatial information which can be drawn accurately without being fixed to a higher global coordinate system. However, when the drawing needs to be related to a higher level in a mapping context with data from many different sources, tools in ArcMap can easily reposition a CAD file and integrate it into that higher level without altering the CAD file.

First thing is to find out two points on the CAD file that matches with two points in the map for which we can use the Georeferencing toolbar in ArcMap.

Different tools on the toolbar can support different workflows and below listed is an easy way to describe georeferencing a CAD file.

First step is to load the CAD drawing and ensure that one of the CAD feature layers are listed in the drop down menu of the georeferencing toolbar.

Zooming to the place roughly on the map where the CAD drawing is to be related is the next step. You can use the ‘fit to display’ tool on the menu to fix the CAD file in the map frame.

ArcMap snapping helps accurate placement of the CAD file which makes precise selection of control points based on existing geometry. Use the ‘rotate’ tool if the CAD file needs to be rotated to get the drawing nearer to its final position. This enables easy picking of control points.

You can use the interactive scaling tool also for the above mentioned reason.

Now when you select the ‘update georeferencing’ option, this creates a .WLD file that will be read from now on to put your CAD file in the right place.

Finally, the coordinates are always adjusted into this position. Now you can select a coordinate system for your CAD drawing so that you can assign or project its coordinates with reference to the map or during any other geospatial operation.

Regards
SBL GEOMATICS
Article By : RARIMA N S

Ornithology and GIS

During spring, flocks of migratory wading birds arrive from their natural habitat, which would be usually intolerably cool during winter, to a critical non-breeding habitat on the tropical places.

Protection of these migratory birds is a concern that needs real attention. Some of these birds from northern hemisphere fly more than 20,000 km a year in search of a suitable dwelling place for survival during the winter season.

The use of GIS and remote sensing technology can be used as an integral part to trace the migrating location of these birds from field mapping to reporting of the location.

One tip to find the birds of migration is to identify their food habit. This would give an idea of their prospective migrating location with regard to the availability of the specific food.

For instance, if we take the birds that usually migrate from Siberia to the tropical North coast of Australia. These migratory birds feed on small animals that live in mud such as crabs, snails and worms. These birds naturally migrate to the area of low muddy lands of Australia to feed and refill their energy for their journey back to their natural habitat.

Using compatible and innovative GPS units and enough field staff, samples can be collected from various points of the expected area of migration by producing progress maps and occasional species maps. By these procedures, even the presence of any new species in the area also can be identified.

To cite another example, some migratory birds have time and again halted in Malaysia during their roosting season that usually lasts from November to March because of its Matang Mangrove Forest.

The arrival of these migratory birds was observed by The Department of Wildlife and National Parks and they have decided to create a GIS database in order to study the biodiversity and sustainability of migratory birds.

Finally, they made a GIS database for the migratory birds and conducted an overall analysis on the captured data. The methodology run from need assessment to data collection, database development and system integration. This finally resulted in an analysis on the trends of bird migration, the properties of ecosystem, environment sensitivity analysis and spatial statistic analysis on the distribution of the migratory birds.

As already mentioned, the resultant migratory bird’s database contain statistical results on the trend of bird migration which in turn helped to identify the endangered species of migratory birds. When the endangered species are classified, measures and procedures for the maintenance of the mangrove areas are taken.


The database of the migratory birds with reference to the diversity and sustainability of the birds can been developed using ArcView 3.2, MapObject 2.0, Microsoft Visual Basic 6.0, AutoCadMap 2.0 and S-Plus 2000.
Regards
Geospatial services
Article By: RARIMA N S

Advantages of Using GIS Services in Oil & Gas | Petroleum industry

The use of Geographic Information Systems (GIS) is gathering momentum in Oil and petroleum industry as a powerful tool for analyzing and displaying data.

Geomatics services can be applied in various stages during the development of projects, including: Petroleum Exploration, Production, Managing Facilities & Pipeline Management

Petroleum Exploration:
Gis facilitates the analysis and integration of a lot of different types of data such as satellite imagery, seismic surveys, digital aerial photo mosaics, surface geology studies, subsurface and cross section interpretations and images, well locations, and existing infrastructure information.Combined Image Processing can reveal underground Geological Information.The remote sensing detection of petroleum is based on the characteristic analogy and analysis of remote sensing information from known oil fields. The thinking way is as follows: micro-seeping of hydrocarbon- ground effect- remote sensing detection is certainly gainful. Exploration software and GIS are essential for geologists searching for petroleum and mineral deposits.

One specific exploration application involves the creation of reconnaissance maps. Uses of GIS in exploitation projects are perhaps more varied because exploitation evaluation typically deals with more extensive data sets than those typically used in exploration settings. Exploitation approaches are generally applied to mature producing areas where well control is dense, whereas exploration projects may not involve any wells at all. GIS is a particularly effective technology that enables exploration and exploitation teams to share information, analyze data in new ways, and integrate the evaluation process.


Production:
Innovative GIS technology is ideally suited for the overlay analysis of geographic, infrastructure, business conditions, and environmental factors and which can be integrated with other business risk or economic business planning engines to provide a focused business solution tool set.

Managing Facilities:
A large integrated oil company must keep track of every minute detail from drilling platforms to pipeline networks and to refineries for their advancement in this highly competitive business area. Geospatial information can be aptly used to map the gathering and transmission of products to a facility.

Pipeline Management :
Geomatics programs can be utilized to monitor the condition and flow of pipelines and determine the best pipeline locations to transport oil off the fields and to the refineries. Pipeline Management is a process by which you continually evaluate your active opportunities (from prospects to booked customer) for their balance of QUANTITY and QUALITY.

Some of the GIS solutions currently offered by SBL In Oil and Petroleum Industry:

1. 3D Modeling
2. Photogrammetry
3. Lidar Data Processing
4. GPS Navigation
5. Corporate GIS data management
6. Map production and presentation
7. Digital Elevation Modeling and Hydrological Modeling
8. Environmental sensitivity analysis and modeling
9. Network analysis
10.Pipeline route optimization and pipeline leakage risk
11.Internet mapping and image web server solutions
12.Work flow analysis
13.Conversion of data to GIS format
14.Linkage of oil spill model to GIS.
15.Retail market analysis.
16.Distribution analysis.
17.Market pattern analysis by demographics.
19.CAD Drafting and Designing
20.CAD to GIS conversion
Retail outlet supply routing and many more…

We hope you found it useful. For more information about the applications of GIS Services in various sectors Please visit the following link.

Gis Service Provider