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August 24, 2009
3D Digital Elevation Models -- Accuracy and Use
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Susan Smith - Managing Editor


by Susan Smith - Managing Editor
Each GIS Weekly Review delivers to its readers news concerning the latest developments in the GIS industry, GIS product and company news, featured downloads, customer wins, and coming events, along with a selection of other articles that we feel you might find interesting. Brought to you by GISCafe.com. If we miss a story or subject that you feel deserves to be included, or you just want to suggest a future topic, please contact us! Questions? Feedback? Click here. Thank you!


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GISWeekly examines select top news each week, picks out worthwhile reading from around the web, and special interest items you might not find elsewhere. This issue will feature Industry News, Top News of the Week, Acquisitions, Agreements, Alliances, Announcements, Financials, People, New Products, Around the Web and Events Calendar.


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Industry News

3D Digital Elevation Models -- Accuracy and Use

By Susan Smith


In a recent webcast, Intermap Technologies, known for its NEXTMap 3D elevation models, talked about the importance of digital elevation models (DEM) and answered the question, “What is a DEM?”


click to enlarge [

Grand Canyon, Arizona--

In this colorized shaded-relief digital terrain model (DTM) in 3D perspective, the Colorado River begins its descent into the Grand Canyon from the lower left and cuts across the Kaibab Plateau as it continues its journey westward to the Gulf of California.
Topics included: What different types of DEMS are there, different spatial data types associated with them, what technologies are used to create them, understanding vertical accuracy as well as posting cell size, and different types of applications that can benefit from DEMs.


Kevin Thomas, vice president, marketing and David Buhner, manager of data processing for Intermap explained the difference between vector based and raster data. Vector based data has points with an xy coordinate. It gives data a lat long grid coordinate to understand location. Points can be connected using lines, and lines between points give you distance between points. To take points and close them gives you a polygon. Vector based is for the most part just xy.


Raster data: there are two types of raster data, the first being imagery. Different types of technologies can collect imagery. With image data you can understand that if you get down to each pixel in an image, it can give you attribute such as color, or greyscale that will be a shade. The other type of raster data is DEM data, which lets you understand elevation with color.


Each “cell” in a 3D DEM contains an elevation value, according to Thomas. A DEM can be lain on its side to get a better visualization of what the terrain is like.


How are DEMs produced?


click to enlarge [

Jakarta, Indonesia --

Flood risk modeling application that depicts a steady-state 3.6 m storm surge in Jakarta , the ninth most densely populated city in the world.
Photogrammetry was the first remote sensing technology developed, which involves a camera on the front of a plane and on the wings. They would use triangulation to understand the distance between plane and the ground, based on photography. With stereophotogrammetry there is a laser on the bottom of the plane, and the goal is to find precise elevation data between two points. LiDAR has laser pulsing and a point based distance system that can calculate distance between distance of land and elevation distance. There are GPS stations with both LiDAR and radar which collect survey points which assist in the surveying and processing of data.


The Shuttle Radar Topography Mission (SRTM) obtained elevation data on a near-global scale to generate the most complete high-resolution digital topographic database of earth. SRTM was comprised of a specially modified radar system that flew onboard the Space Shuttle Endeavour during an 11-day mission in February of 2000. It covered the majority of the earth and collected raw radar data of 9 terabytes, which was considered a huge amount of data at that time. SRTM is still used worldwide.


Accuracy


The means of collecting different types of DEM data varies. IFSAR has an accuracy of 1 meter. Photogrammetry and LiDAR have the most accurate data at 20 centimeter vertical accuracy.


Buchner said you need to look at what you’re trying to accomplish. If you’re doing a floodplain, 20 feet won’t be accurate enough. “You need to ask the right questions if you’re sourcing data,” he said.


LiDAR is the most accurate of the platforms, but very costly, as it takes long time to collect. Photogrammetry, is also some of the most accurate but time consuming. SPOT satellite and Intermap IFSAR are not quite as accurate but offer 1 meter data.


There are measurements that are predicted as opposed to those that are actual. Prices range according to vertical accuracy. “In the case of vertical accuracy, we take our dataset and compare it against a dataset that is deemed as truth and RMSE vertical accuracy,” said Buchner. “We don’t say our data is perfect for all applications. If you’re doing a small engineering project for a small area and you need highly accurate elevation data LiDAR is a great solution for you.”


Buchner added that for large areas like a metro area or state, this type of data might be overkill. One meter for a wider area is great as it saves costs, and can blend with 27 meter LiDAR for close up smaller areas as needed.


Cell size represents the spacing between your points, and different postings range from 30 meter all the way to 1 meter. This means that every 30 meters you’ll have a pixel or a point, and have an xy coordinate associated with it. With one meter you have more dense data. If you have postings of a smaller nature, the data will be more accurate.


A one-meter posted product for an entire metro area is a lot of data to deal with. Some people have to resample it down to a 25 meter product because it becomes too much data.


The horizontal accuracy of data has to do with the accuracy of points, but it is in conjunction with posting and vertical accuracy. With the size of your posting goes the size of your data set.


Types of DEMs available


A digital surface model (DSM) includes tower, trees, anything grown or built up on land. Whether radar or LiDAR – the view is what you would see from a birdseye view or higher.

Digital terrain models (DTMs) take out such features, manmade features, brush or trees to show true bare earth. Some radar can see through the earth’s crust, but most will bounce off what it first comes in contact with. “There are also ways and types of software and look at a DSM and see different items in surface, create algorithms and understand what’s underneath,” said Buchner.


Intermap has DSM and scraping of the earth in its model to make sure it’s removing the artifacts. “We have a team of employees in the production facility that manually go into every single tile and square mile and manually ensure the bald earth is as is before it goes to a validation group to ensure the product that is put on the shelf is correct. The customer doesn’t have to do anything, just plug it in to their application,” said Thomas.


Different applications for a DEM include: contour generation, enhanced mapping applications, viewshed analysis, flood mapping, telecommunications such as cell tower coverage, 3D road generation, geology, urban mapping, vegetation, wind power generation and watershed analysis.


Intermap’s high-resolution NEXTMap 3D DEMs were accepted as a source for updating FEMA flood maps this week as well, announced at the recent Association of State Floodplain Managers (ASFPM) national conference in Orlando, Florida.


The company’s NextMap DEM data has been used in Europe to update flood risk maps for the insurance industry, and flood risk products based on the NextMap data are used in UK, Germany and Switzerland. The addition to FEMA flood risk maps should make a large difference to the agency’s ability to anticipate and respond to flood crisis situations.


Data is immediately available from an Intermap representative, online at
www.TerrainOnDemand.com, or through a network of certified distribution partners worldwide.


Top News of the Week


Autodesk reported financial results for the second quarter of fiscal 2010. Revenue was $415 million, a decrease of three percent sequentially and 33 percent compared to the second quarter of fiscal 2009.
Press release


Global Mapper Software LLC is excited to announce the availability of our most significant release ever, Global Mapper v11.00. Just
download that file and run it to install v11.00. It will install alongside any existing Global Mapper version, so you don't have to worry about losing what you're currently working on to evaluate it.


Acquisitions, Agreements, Alliances


The Open Geospatial Consortium, Inc. (OGC) and the Mortgage Industry Standards Maintenance Organization (MISMO) recently signed a memorandum of understanding (MOU). Under the terms of the MOU, the organizations will collaborate on standards development and outreach to enable and promote the use of Web based geospatial technologies in real property transaction applications.


GeoDecisions, an information technology company specializing in geospatial solutions, announces a strategic partnership with Garmin, to extend the company’s services and solutions with Garmin’s proven devices and equipment.


Announcements


The United States Geospatial Intelligence Foundation (USGIF) announced more confirmed speakers for its sixth annual GEOINT Symposium, which takes place Oct. 18-21, 2009, at the Henry B. Gonzalez Convention Center in San Antonio, Texas.


Newly confirmed keynote speakers for GEOINT 2009 are the Honorable Dennis C. Blair, director of national intelligence, and retired U.S. Air Force Gen. Bruce Carlson, director of the National Reconnaissance Office. They join already confirmed keynote speakers U.S. Navy Vice Adm. Robert Murrett, director of the National Geospatial-Intelligence Agency; U.S. Air Force Lt. Gen. David A. Deptula, deputy chief of staff, U.S. Air Force intelligence, surveillance and reconnaissance; and the Honorable James R. Clapper Jr., under secretary of defense for intelligence.


INTERGEO is a world trade fair for geodesy, geoinformation and land management – and the congress trade fair in Karlsruhe from 22 to 24 September will also be a presentation platform for innovative start-up companies. For the first time, the German Federal Ministry of Economics and Technology (BMWi) is promoting the joint presentation of the Open Source Park (OSP) along with ten companies. Experts from free and open source GIS software projects have demonstrated their considerable innovative skills at INTERGEO over the last few years under the patronage of the Open Source Geospatial Foundation (OSGeo).


Awards


The Environmental Systems Research Institute (ESRI) recently recognized Science Applications International Corporation (SAIC) with their 2009 Federal Business Partner of the Year Award for outstanding achievements in the areas of sales, innovative product development, and fostering ESRI technology into key products.


People


Tensing announced that Tom Matthews will be the new Managing Director at Tensing USA. Matthews will be handling all sales in the North American market, as well as running the US office. “We are very pleased that Tom has joined our team. He will be an asset in expanding our footprint in North America,” said Dirk Verbeek, CEO of Tensing. The new appointment takes effect immediately.


URISA is pleased to announce the results of its 2009 Board of Directors Election. Cy Smith, GISP will become President-Elect of the association and Carl Anderson, GISP, David DiBiase, GISP and Twyla McDermott, GISP will begin their terms as members of the Board of Directors, at the close of URISA's 47th Annual Conference in Anaheim, California, September 29-October 2, 2009.


New Products


ESRI's newest release of ArcGIS Explorer became available for free download, providing a highly visual and intuitive way to explore, share, and present your geographic information. It is an ideal means of making your authoritative geographic information system (GIS) data available to people who are not GIS experts.


ThinkGeo announced the release of an initial public beta of
Map Suite Routing, a new extension for their Map Suite 3.0 family of GIS software developer components for .NET. Map Suite Routing makes it easy for developers to add routing features to their Map Suite applications, including turn-by-turn directions, waypoint support and area avoidance. Now, developers can deliver a whole new level of features and functionality to their customers through their Map Suite GIS projects.


GGP Systems will be launching the latest version of its geographical information system (GIS) at the forthcoming Association of Geographic Information (AGI) GeoCommunity ‘09. GGP GIS 2009 includes advanced spatial data storage functionality, improved data security and user authentication and support for Windows Vista, Windows 7 and Windows Server 2008. GGP GIS 2009 will be on show at the AGI GeoCommunity ’09 event the biggest independent GI conference in UK, which takes place from the 23th to 24th September at the Holiday Inn, Stratford–upon–Avon, UK.


TerraGo Technologies, a provider of geospatial collaboration software solutions, announced the general availability of its Publisher for Raster version 5 software. The new solution not only gives users the ability to extend the access and application of their imagery assets, but also provides analysts new productivity tools that make it easier to generate large volumes of portable, actionable images via a geo-referenced PDF file (GeoPDF) for greater geospatial collaboration capabilities.


KOREM Inc., a spatial system integrator and consulting company, announced the availability of its custom Broadband USA application data package and consulting services. The data package includes spatial data for terrestrial broadband providers (cable TV and wireline carriers) trimmed to approximate actual service areas as well as Census block level spatial data that includes many of the requisite attributes for the application process for broadband funding under the American Recovery and Reinvestment Act of 2009.


Intergraph now offers a public safety computer-aided dispatch solution that supports Google Maps API Premier, the enterprise version of the Google Maps API. The ability to view Google Maps provides communications and field personnel with advanced situational awareness and promotes effective and efficient response to mitigate incident impact and save lives.


SPADAC, a provider of spatially enhanced technology solutions, has launched Signature Analyst 3.2, the latest version of its advanced geospatial predictive analytics tool. Feature enhancements include improved performance through multi-threading indexing, which reduces processing times and increases efficiency, and improved factor management and organization, along with more advanced modeling capabilities.


Around the Web


Jack Dangermond’s Digital Mapping Lays It All Out by Donna Howell, Investors Business Daily, August 14, 2009


SuperField 3, the Best Choice for Lightweight Mobile GIS Users PR Log, August 14, 2009


GIS goes vertical, with integration across state, local, federal lines by Patrick Marshall, Government Computer News (GCN), August 10, 2009


Indian Space Research Organisation ISRO head on’s with Bhuvan against Google Earth Voice of Sikkim


Events

 
Date:
August 25, 2009
Place: USA

Technology advances in both hardware and software offer opportunities. This webinar provides insight into the changing graphics landscape, including the 5 key trends, and provides insight on how HOOPS can help dramatically improve your application's graphic capabilities, particularly in the areas of visually rich, GPU-based rendering and smooth handling of very large models.



Time: 10-11am EDT

Date:
August 26 - 28, 2009
Place: Newton, MA USA

Caliper Corporation invites you to attend training for Maptitude
Geographic Information System for Windows.
The classes will be at our training center in Newton, Massachusetts.Caliper training is the fast, cost-effective way to learn how to make
the most of your Maptitude software investment.The three days of training are aimed at every type of user. The course
covers skills and tools valuable to both new and experienced users of
Maptitude and participants learn the fundamentals of Maptitude and
related GIS concepts.

Date:
August 28 - 29, 2009
Place: J N Tata Auditorium

Indian Institute of Science, Bangalore , India

With almost 300 million Indians living in urban areas (in 3700 towns
and cities), the country has the second largest urban population in the
world and it is growing at a rapid pace of over 31 percent over the
last decade due to higher employment rates in urban areas. It comprises
of about 30 per cent of the total population in urban areas and
contributes to over 60 per cent of the country's GDP.
Date:
August 31 - September 3, 2009
Place: bcc Berliner Congress Centre

Berlin, Germany

SPIE Europe Remote Sensing Symposium welcomes you to this exciting meeting covering the fundamental optical science as well as the application of the underpinning technologies in advanced remote sensing. Together with SPIE Europe Security + Defence, SPIE Europe Remote Sensing embraces a broad cross-section of emerging technologies for remote sensing applications.


Date:
September 2 - 5, 2009
Place: Baska, Krk Island, Croatia (Hrvatska)

This four-day event aims to gather GNSS experts and focuses on GNSS problems and vulnerabilities, as well as on developments aiming to improve the accuracy and reliability of GNSS.


The unique environment of Baska and its natural resources and rich history, combined with friendly hospitality will again create an inspiring atmosphere for ideas and knowledge exchange.


Date:
September 9 - 12, 2009
Place: Beijing International Convention Center

China

You are cordially invited to attend the 6th International Symposium on Digital Earth ( ISDE6 ) with the theme of Digital Earth in Action and to visit Beijing, China in September, 2009. ISDE6 will continue the tradition of gathering world-class scientists, engineers and educators engaged in the fields of digital earth, earth observation, geo-informatics and relevant applications to review the progress of Digital Earth during the last decade and discuss the achievements of Digital Earth and the recent developments.


Date:
September 9 - 11, 2009
Place: Capital Plaza

Frankfort, KY USA

Conference Highlights:


• Geocaching in historic downtown Frankfort - this could be the best  course to date. (Prizes for the winning team)

• Keynote by former Governor and Senator Julian Carroll

• Full schedule of user Presentations and Panel discussions

• “Tailgating with the Vendors” Reception

• URISA Project Management Workshop with Pete Croswell

• ESRI Workshop on ArcServer

• LiDAR Workshop

Date:
September 10 - 11, 2009
Place: 1919 Saskatchewan Drive

Regina, SK, S4P 4H2 Canada

ESRI Canada is pleased to invite you to join other GIS professionals for this exclusive opportunity to learn about the latest advances in GIS technology and hear first hand how others in your community are using a geographic approach in their work.


Date:
September 10 - 12, 2009
Place: Sheraton Denver Hotel

1550 Court Place, Denver,, CO 80202 USA

CLEAR promotes regulatory excellence through conferences, educational programs, networking opportunities, publications, and research services for those involved with, or affected by, professional and occupational regulation


Date:
September 13 - 16, 2009
Place: Columbus Convention Center

Columbus, OH USA

 APWA develop a relevant and exciting education program for the 2009 Congress by sharing your vision for the future of public works and your trends- analysis and scenario-planning techniques, plus – contribute to the overall public works body of knowledge by sharing your expertise and real-world solutions.


Date:
September 13 - 17, 2009
Place: Westchase Hotel

Houston, TX USA

The GIS for Oil & Gas Calgary Conference built upon the momentum from GITA’s GIS for Oil & Gas Conference held in Houston, Texas, every September—which consistently experiences record-breaking attendance. In 2008, this was the place to get real solutions to Canada’s biggest oil and gas challenges.


Date:
September 13 - 15, 2009
Place: Albuquerque

New Mexico, NM USA

The International Map Trade Association (IMTA Americas) is having its conference & trade show at Hotel Albuquerque in Old Town,  Albuquerque, New Mexico.  The dates are September 13 – 15, 2009.  Representatives from around the world come together annually to see new maps, atlases, globes, and other related products at this event.  Attendees are offered an array of cutting edge workshops and training sessions to broaden their knowledge.  Visit www.maptrade.org for all details.


Date:
September 15, 2009
Place: Radisson Hotel Boston 200 Stuart Street

Boston, MA 02116-5442 USA

 MapInfo Professional v10.0's 'new look' includes colourful and modern toolbars that can be docked anywhere to save screen space and a new Layer control that provides fast and intuitive access to layer information.



Date:
September 15 - 18, 2009
Place: Union Station Hotel

1001 Boradway, Nashville, TN USA

The NASCLA 47th Annual Conference is set for September 15 – 18, 2009 at
The Union Station Hotel.  Typically we have around 100 attendees who
are executive directors, board members and employees of contractor
licensing boards from around the country.  It is an opportunity to
bring these regulators together to discuss hot topics in our industry.


Date:
September 16 - 18, 2009
Place: Denver, CO USA

GIS in the Rockies is the intermountain west's premier
geospatial information and technology conference. The conference offers
opportunities for industry professionals to learn more about geospatial
technology issues and business-centric strategies supporting every
vertical market touched by the geospatial industry.
Date:
September 16 - 18, 2009
Place: Crowne Plaza North Hotel (formerly Marriott North Hotel)

6500 Doubletree Road, Columbus, OH USA

OGRIP has created the Ohio GIS Best Practices Award presented annually at the Ohio GIS Conference.  This program is designed to recognize organizations in Ohio that have or are implementing GIS in a manner consistent with OGRIP’s goals and objectives.  OGRIP encourages your organization to consider submitting an application for your GIS program.


Date:
September 16 - 18, 2009
Place: Brichwood Hotel & O R Tombo Conference centre

Johannesburg, South Africa

Map Africa 2009 shall host a Special Meet that will
bring together an elite group of NMO’s of Africa to share their
visions, mandates and programmes with select group of industry
representatives. This event is being proposed to provide a platform to
NMOs to share their ideas and future plans with industry
representatives and facilitate public-private partnerships. At the
forum the representatives of the NMO alongwith some large user
organisation will be invited to present their views and expectations
with the industry. The forum will serve two purposes.


Date:
September 17 - 18, 2009
Place: Crowne Plaza Chateau Lacombe

10111 Bellamy Hill NW , Edmonton, AB, T5J 1N7 Canada

ESRI Canada is pleased to invite you to join other GIS professionals for this exclusive opportunity to learn about the latest advances in GIS technology and hear first hand how others in your community are using a geographic approach in their work.


Date:
September 17, 2009
Place: USA

Join the PODS Association for the 5th annual user group meeting on Thursday, September 17, 2009 from 8am to 5pm at the Marriott Westchase in Houston, TX.  Attendees will have the opportunity to meet with other operators and service providers to learn how they are using the PODS data model to meet their business and regulatory needs.  Included in this meeting will be updates from the working groups, information about the Technical Committee, and the future plans of the Board of Directors. This meeting is open to non-PODS members that are interested in learning more about the PODS organization. Registration is required.



Thursday, September 17, 2009,

Houston, TX from 8 am to 5 pm

Date:
September 17, 2009
Place: Marriott Westchase

Houston, TX USA

The annual PODS User Conference will be Thursday, September 17, 2009,
from 8am to 5pm at the Marriott Westchase in Houston, Texas, USA.
Date:
September 17, 2009
Place: USA

Join us at our online information session to learn more about how you can earn a certificate in Geographic Information Systems completely online. During the info session you will get to learn more about the certificate and ask questions.


 

Visit
http://advanced.jhu.edu/academic/environmental/gis/ to learn more about our certificate program.

Date: 09/17/2009

Starts: 7:00 PM - Ends: 9:00 PM

Date:
September 21 - 25, 2009
Place: Port de l'Aber Wrac'h

Landéda , 29870 France

The aim of COSIT is to bring together researchers from different disciplines for an intensive scientific exchange. This aim is facilitated by the presentation and discussion of a restricted number of papers and posters -- the most innovative and significant recent contributions -- rather than papers covering all advances in the field.

Date:
September 21 - 22, 2009
Place: Hilton, Altamonte Springs

FL USA

Workshop Program includes 2 days of great training opportunities not
only through technical presentations from ESRI and the GIS industry,
but also from users in the GIS community who have lived and learned. Mr
John Calkins, Corporate Technical Evangelist, ESRI will be our Keynote
Speaker at the Workshop
Date:
September 21 - 23, 2009
Place: Hilton Nashville Downtown

Nashville, TN USA

Join us for
the 2009 ESRI Health GIS Conference and learn how health and human services
organizations worldwide are improving our health with GIS.
Date:
September 22 - 24, 2009
Place: Karlsruhe, Germany

INTERGEO is the world’s largest event and communication platform for geodesy, geoinformation and land management. The trade fair and conference cover all the key trends that crop up along the entire value-added chain – from geo-based information surveys and data processing to integrated applications.
Date:
September 22 - 23, 2009
Place: 2200, rue Mansfield

Montréal, QC, H3A 3R8 Canada

ESRI Canada is pleased to invite you to join other GIS professionals for this exclusive opportunity to learn about the latest advances in GIS technology and hear first hand how others in your community are using a geographic approach in their work.


Date:
September 22 - 24, 2009
Place: Holiday Inn, Stratford Upon Avon

Bridgefoot, United Kingdom

The

AGI conference is the biggest independent GI conference right at the
heart of the UK event GI calendar and delivered by the nation's
dedicated GI membership association. Now well established as a
centrally located residential conference, AGI GeoCommunity has become
extremely popular. AGI GeoCommunity is ideally structured for a great
diversity of activities; plenaries, keynotes, conference papers,
workshops, debates, networking, social activities and much more.



Date:
September 22 - 25, 2009
Place: Savannah International Convention Center

Savannah, Georgia

The Institute of Navigation hosts three technical meetings each year:
The International Technical Meeting in January; the Annual Meeting in
June; and the Satellite Division Technical Meeting, ION GNSS, in
September.
Date:
September 22 - 23, 2009
Place: 44045 Five Mile Road

Plymouth, Detroit, MI 48170 USA

PLM Road Map™ 2009 is a strategic conference focused on the critical trade-offs shaping product development. Attendees at PLM Road Map™ 2009 will have their current thinking on product development challenged in a series of highly charged presentations. At PLM Road Map™ 2009 you will find out first hand which issues are currently confronting end users.


Date:
September 23 - 24, 2009
Place: Holiday Inn

Bridgefoot, Stratford Upon Avon, England, United Kingdom

The AGI conference is the biggest independent GI conference right at the heart of the UK event GI calendar and delivered by the nation's dedicated GI membership association. Now well established as a centrally located residential conference, AGI GeoCommunity has become extremely popular. AGI GeoCommunity is ideally structured for a great diversity of activities; plenaries, keynotes, conference papers, workshops, debates, networking, social activities and much more.




You can find the full GISCafe event calendar here.


To read more news, click here.



-- Susan Smith, GISCafe.com Managing Editor.


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