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2006 February 23


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Editor's Introduction

This week I continue last week's focus on change detection, by featuring conversations with Peg Shippert, RSI's technical product manager for ENVI, and with François Smith, a senior scientist at MDA Federal. Shippert mentions three new radar remote sensing satellites and predicts that they will create a new market; Smith outlines the different kinds of change detection techniques and software. I also report on yet another story about digital mapping in the mass media, correct a headline from last week, and bring you my usual round-up of news from press releases.

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Change Detection — RSI

Last week RSI, a subsidiary of ITT Industries, released ENVI RX Anomaly Detection Tool , a free plug-in for ENVI 4.1 and 4.2 that enables ENVI users to identify anomalies in geospatial images by automatically locating areas in an image that are different from the overall background. The ENVI RX Anomaly Detection Tool uses the RXD anomaly detection algorithm to extract anomalous features from spectral images. Users select the input file and the tool then highlights the pixels that are different from the general image background. According to RSI, the software does not require any expert knowledge of image processing. After detecting anomalies, analysts can use other tools, such as the ENVI Spectral Analyst, to try to identify the anomalous features.

In defense and intelligence scenarios, applications for anomaly detection include locating targets such as military vehicles and identifying soil disturbances that might indicate land mines or recent troop movements. Other applications for anomaly detection include identifying locations of crop stress for precision agriculture applications, locating areas of infected trees for forestry applications, and finding rare minerals for geology applications.

I discussed change detection with Peg Shippert, RSI's technical product manager for ENVI. The product, she told me, includes two kinds of change detection tools. One of them compares two images, highlights the areas that have changed — that is, where pixels have larger or smaller values — and provides different shades of blue or red, depending on whether the change is positive or negative. The larger the change, the brighter ENVI will highlight the changed pixels — thereby displaying the degree of change as well as the direction of change. "It's a very simple tool," says Shippert, "that just looks for that type of change. It can be useful, for example, for radar images before and after some flooding. You can also use it for more gradual changes, such as those in vegetation types." This tool is not suited for spectral imagery, Shippert explains, but it can be used for radar imagery, which doesn't have spectral content, or to compare one band of a multi-spectral image to the same band taken at a later time.

The other ENVI change detection tool is more useful for multispectral data or gray-scale images, because it classifies all of the pixels in those images into categories. If, for example, you have land use classes — such as urban, forest, and agriculture — it detects where those classes have changed and how much acreage has shifted from one category to another. It displays the information using both images and tables. Users define the classes and, therefore, can use the tool to detect and analyze different types of change.

RSI added those change detection tools into the ENVI product a couple of years ago. In recent releases the company has not added new change detection tools, Shippert told me, but it has added many new tools. "In the last version, which came out last September, we added the ability to do some more sophisticated classification based on vegetation properties. For example we have some ways to create maps of fire fuel loads, agricultural stress, and forest health. They can be used in the change detection tool as well, if you have before and after images."

According to Shippert, probably the most significant new change detection project at RSI is the development of tools to extract features from images based on spatial information. They would allow users to take an image and extract some vector layers that show particular features of interest — linear features, such as roads or coastlines, or areas, such as fields, parking lots, or bodies of water. "Once you've extracted those features from the imagery," says Shippert, "you export them into shapefiles or other vector formats. [Using before and after images] you would have two different vector layers that showed those features before and after and those could be overlaid on top of images or just shown together so that the changes could be apparent."

Additionally, says Shippert, "we're always looking for new technology in terms of change detection." This year, she points out, some new types of radar sensors are being launched: the Japanese Advanced Land Observing Satellite (ALOS), MDA's RADARSAT-2, and the German TerraSAR-X. "All three of those sensors are going to have polarimetric SAR capabilities. And there are some very interesting change detection things you can do with polarimetric SAR data. The trick is going to be having the software tools to process the data properly to get at that change detection. I think that polarimetric change detection might be big in the future. It's a type of data that has not been available commercially before and now we're having three sensors go up in a year — it's going to be creating a new market, basically." A fourth satellite, which Shippert did not mention, is the Italian Cosmo - SkyMed.

Responding to Ken Stump's argument, that it is better to compare "two really good maps" rather than to just detect spectral shifts, Shippert says: "Yes, that's true, but the questions is: how are you going to get those really good maps? The point of doing change detection with imagery is to create a shortcut to making those kinds of maps and save the time of going out in the field." She ads: "The more multispectral data you have, the better idea you have of what the materials are on the ground that you are looking at. Sometimes having that whole image overview of things helps you to interpret things better." Additionally, she points out, going on the ground and creating a map is often not an option. "For example, the military often has this problem: they don't have the luxury of going on the ground in the area, yet it is very important to them to detect various types of changes — so they rely on the imagery."

Change Detection — MDA Federal

This week I discussed change detection with François Smith, Ph.D., a senior scientist at MDA Federal. He manages several of the company's projects and does a lot of R&D; for technical processes.

MDA Federal, Smith told me, produces many of the datasets for the coastal change analysis program of the National Oceanic and Atmospheric Administration (NOAA). These datasets are five year updates for a baseline 23-category land cover produced from mid-resolution Landsat data for all the coastal regions of the United States. "Change detection," Smith explains, "provides a much more cost-effective means for updating land cover, as opposed to re-doing an entire land cover. Typically we use mid-resolution, 30 meter, Landsat or Landsat clone-type data with six bands. We've also developed some new and different procedures for doing change detection, using these mid-resolution data sets. For example, we have a technique called CCA, which stands for cross-correlation analysis. It allows you to use different seasonal dates of imagery and yet still produce actual change." MDA Federal does not produce and sell change detection tools. However, it has distributed limited licenses for CCA, mainly for government use.

One big limitation for doing change detection, Smith told me, is repeat coverage. Landsat satellites, for example, repeat their cycle every 16 days and do not have pointable optics, so they are hard to use for short-term change detection. There are multiple missions planned for putting additional satellites into space, however, and one proposal under discussion would deploy a whole constellation of satellites that would be able to provide same-day repeat coverage. "That will be a huge thing," Smith says. Analysts can also approximate this result by using techniques that allow them to use data from different platforms.

Another big hindrance to change detection, Smith points out, is clouds. To deal with this, MDA Federal has developed a method that replaces imagery under clouds, though it obviously cannot detect change that's occurred under clouds. "It's not just a straightforward replacement of data," Smith explains. Rather, "it is a method for predicting values that would be under clouds, based on a regression tree approach." The method takes the clouds out of before and after images and uses data that the two images have in common to develop rules, which analysts then apply to the areas where there's no data due to cloud coverage. "Even though that does not give you change information," Smith says, "it does fill in all the holes and allow you to have a continuous data set."

MDA Federal's change detection tool is tailored to deal with issues of seasonality and to update land cover, Smith told me, because the company does a lot of work of that nature. Most of the change detection algorithms that are offered within software involve the Image Differencing (ID) technique: they first try to calibrate the imagery from two data sets and then detect differences with a subtraction. That is another good way to look at change, Smith says, but it requires anniversary date imagery and makes a lot of assumptions. "For our purposes," he told me, "we weren't getting quite the accuracy or the type product that we needed. We also just didn't have the imagery. It is too difficult to get the imagery within the parameters necessary to use that successfully."

Other techniques include band replacement, Multi-Date Composite (MDC), Multi-Date Principal Components Analysis (PCA), and Change Vector Analysis (CVA). According to Smith, CVA, which creates vectors related to directions of change, is "a little more difficult to run," but has the advantage that it allows the user to determine what changed to what degree in what direction. The principal components technique consists of dumping all the bands and imagery from both sets into one file and then running the principal components in the hope that one of them will correspond with change. Multi-date classification allows the user to, say, input six bands for each of two dates, overlay one on the other, and classify the result. "That way," Smith says, "you can classify out the change." This technique, he adds, is popular and does not necessarily require anniversary dates.

Smith once reviewed four different commercial change detection software packages and compared them to his company's CCA to determine which isolated change the best. He concluded that "CCA worked better than, for example, principal components change detection or a multi-date classification."

Change detection, Smith explains, can be grouped into two types: pre- and post-classification. "Pre-classification," he says, "is change that you quantify based on the imagery; post-classification means that you've classified products from the image data sets and then you've conducted the classification afterwards." MDA Federal, he explains, uses a hybrid approach to update classification data. "We use the classified data along with both image data sets and then we use the result of that to update the classification. Then between the two classification data sets that have been derived we run what's called bi-variate analysis, in which we can determine exactly the percent of every single category that changed. So, we end up with two products: a bivariate analysis, which is a post-classification change detection, and what we call Z scores, which [measure] bi-directional change."

The most common pre-classification change detection technique, according to Smith, is ID. In order to calibrate, people will often run an NDVI (Normalized Difference Vegetation Index) on both data sets. "Because that's looking at the bands relative to each other, it will automatically take out a lot of the radiometric differences," he says. "So, you run the NDVI on both data sets and then you can just subtract one from the other. That's probably the most common type of change detection." According to Smith, most software packages probably use post classification change detection, which generates a change matrix. "So," he says, "image differencing for pre-classification change detection is most common and for post-classification I would say a change matrix."

Smith recommends two texts on change detection: Introductory Digital Image Processing: A Remote Sensing Perspective, 2nd edition, by John R. Jensen (Prentice Hall, 1995), "which has a chapter on change detection and describes each common change detection algorithm," and Remote Sensing Change Detection, by Ross Lunetta and Christopher Elvidge (Taylor & Francis Ltd, 1999).

Briefly Noted

On February 20, the New York Times ran an article titled "Can't Remember Who Whacked Whom? Just Check the Map on the Web Site," reporting on a marketing effort to promote the upcoming season of the HBO show "The Sopranos," which is resuming after a hiatus of nearly two years. According to the article, "in one of the first marketing efforts to use Google's map technology," HBO and Deep Focus, an online marketing agency, "have created an interactive map of New Jersey, using satellite maps from Google, and have highlighted important points of the most recent season's storyline."

The article continues: "The map has about 15 icons in specific areas where scenes took place. When the user clicks on an icon, the scene plays in a pop-up window, which also supplies a description and a list of characters. ... Ian Schafer, the founder and chief executive of Deep Focus, said Google gave permission to use its satellite maps, which have detailed satellite imagery of [Earth], whithout charge. The map will be availabe at beginning [on February 27]. ... Mr. Schafer said the concept of the campaign also mirrored aspects of 'The Sopranos,' which he hoped would add to the appeal. 'The visual concept is, in a way, a surveillance of everything that has happened in Season 5. We are extending that paranoia into the application itself. And it puts it also into a context of reality.'"

Department of Corrections

Last week, I bungled a headline: "MetaCarta Joins Forces With Hitachi" should have been "MetaCarta Joins Forces With the DIA." It was Pictometry that joined forces with Hitachi. My apologies. I have fixed the error in our archives.

News Briefs

Please note: I have culled the following news items from press releases and have not independently verified them.


Colorado Springs Utilities (CSU), a community-owned and operated utility providing electric, water, wastewater, and natural gas services to its population of more than 600,000 metered customers, has selected Miner & Miner's ArcFM Viewer (which runs on ArcGIS Engine) and Redliner Extension as their mobile solution for viewing and redlining spatial information in the field.
     For several years CSU has been using ArcFM, with some customized editing functionality, in each of their service lines to meet specific business requirements for asset and facility management. With 2,000 employees and thousands of field observations made every day, it became essential to have a markup method that would allow integration back into the enterprise. Prior to using ArcFM Viewer and the Redliner Extension, the organization used digital map books for asset and facility viewing, but field workers remained constrained by limited functionality. With the new applications, they will be able to pan, zoom, query, and redline, which will increase cartographic and attribute accuracy.

The Open Geospatial Consortium (OGC), the international geospatial industry consensus standards organization, has adopted the GMLJP2 standard proposed by LizardTech, Galdos Systems, and a consortium of aerospace and geospatial technology companies. GML, a Web-authoring language for delivering and displaying geographic data over the Internet, is based on eXtensible Markup Language (XML) and will be used to define rich geospatial metadata within a JPEG 2000 (JP2) file. This new standard will also drive cross-platform interoperability and rapid Internet distribution for geospatial imagery, enabling customers to quickly and easily disseminate massive geospatial imagery by providing a consistent image format that is vendor-independent.
     LizardTech is developing products to support the addition of GML metadata to JP2 files and provide LizardTech customers more flexibility and interoperability with their geospatial images. The new products are scheduled for availability this summer. Additionally, this opens up opportunities with future LizardTech products, as GMLJP2 can support not only basic image information, but also geographic features, coverages, and topology, enabling new workflows such as using GML to specify which three bands a multispectral image should display depending on the application that opens it, or using sensor model information embedded in the GML to determine how an image should be rendered. Other companies that contributed to the proposal for the GMLJP2 standard were: Boeing, EUSC, SPOT, USGS, ITT, NASA, PCI, Integraph, DMSG, and BAE.

mPower Technologies, a technology consulting firm, software developer, and service organization; and PlanSight LLC, an ESRI-authorized developer and provider of a full range of high quality GIS products and consulting services, have entered a business partnership. Together they developed a new GIS-based land records portal application, CivX Integrator, allowing organizations to create, manage, distribute, and share GIS-based land records data without expensive and time-consuming programming or outsourced consulting.
     Tools within mPower Integrator, combined with software developed by PlanSight, provide a geographic data distribution and query application. CivX Integrator is a way to distribute database and mapping information through a local network or the Internet. Workload and website implementation times are reduced and revenues increased by quickly and efficiently sharing and distributing data from multiple sources.
     mPower and PlanSight plan a full introduction of their application at the upcoming Wisconsin Land Information Association conference, March 1-3. mPower and PlanSight customers include public utilities; municipal, county, and federal government agencies; and real estate developers.

Woolpert, Inc. has purchased a second ALS50 airborne laser scanner from Leica Geosystems. Currently, Woolpert is the only firm in the country to operate two of Leica's ALS systems. The company purchased its first ALS50 in 2003 and, as a result, was able to offer its clients more robust LiDAR (light detection and ranging) products in less time. It needed the second system to keep pace with growing demand for LiDAR data collection from clients throughout North and South America.
     The Leica ALS50 airborne laser scanner is capable of collecting up to 83,000 points per second, with the ability to collect the data day or night. This flexibility, along with LiDAR's unique ability to penetrate tree canopies, makes it a very accurate tool for generating precise digital terrain models.

Intermap Technologies Corp. has signed a second joint development agreement within the German automotive industry for Intelligent Transportation Systems (ITS) applications. The agreement combines the automotive engineering and development expertise from a German automotive manufacturer with Intermap's geospatial databases. The first phase of the agreement will concentrate on developing advanced 3-dimensional road data applications for both performance and safety improvements.
     Since the focus of the development activities are in Europe, Intermap plans to accelerate its NEXTMap Europe plan, beginning with the completion of NEXTMap Germany this year. Intermap's NEXTMap 3D road vector data can improve ITS applications such as vehicle engine control, which can save on vehicle operating costs including fuel and insurance. Improvements in fuel economy through adaptive cruise control, translate directly to reduced costs of operation, as well as reduction in greenhouse gas emissions.
     Companies in the automotive market have told Intermap that they now have ITS technologies waiting to incorporate 3D road data and have been asking suppliers for accurate 3D road vectors. They also state that the existing 2D road data has not been accurate enough for many ITS applications and can even cause problems in their systems. Intermap has been told that it is the first company to present an accurate 3D solution for this issue.
     This agreement underlines the progress Intermap is making in ITS and its ability to attract interest from automotive industry leaders. These joint development relationships will give participating companies the opportunity to showcase the value of incorporating precise 3D road data into future automotive systems. ITS adoption is well underway with navigation systems already present in most luxury vehicles. Various technologies are now being used in concept cars to test ITS functions, such as advanced lane departure warning systems.
     Future safety features such as advanced driver assistance systems (ADAS), are considered to be the largest opportunity for the auto makers. An example of ADAS is the use of highly accurate digital maps to foresee any upcoming abrupt curves ahead and automate a vehicle's capability to navigate the road at an appropriate speed.

The Washington State Department of Transportation (WSDOT) has selected Bentley Systems, Incorporated as its primary provider of software for engineering and surveying practices. WSDOT selected Bentley InRoads software to replace CAiCE as its primary transportation engineering software based on a statewide steering committee review. Integration and interoperability were key factors in choosing the new design platform.
     WSDOT's individual regions will make a gradual transition from CAiCE to InRoads, with the goal being to start all new projects in InRoads. Once WSDOT completes its transition to InRoads, it is anticipated that there will be 150 to 200 concurrent users of the software statewide. WSDOT has also opted to join the Bentley Enterprise License Subscription (ELS) program.

Telvent GIT has signed contracts with Southern California Gas Company (SoCal) and Epcor Transmission Inc. (Epcor) to upgrade the supervisory control and data acquisition (SCADA) systems at both utilities. Telvent will upgrade the SCADA system it had previously installed for SoCal's gas system control center with its latest proprietary OASyS DNA technology. Telvent has also been awarded a contract to upgrade the existing SCADA system used by Epcor Transmission Inc.
     SoCal is a division of Sempra Energy in San Diego, California, the largest natural gas distribution utility in the United States. SoCal currently serves more than 19 million people in more than 530 communities in Los Angeles, California. In total, the company delivers nearly 1 trillion cubic feet of gas annually, or about 5 per cent of all the natural gas delivered in the United States. Epcor is a Canadian company that distributes electric energy to Canadian and North American customers in the provinces of Alberta, British Columbia and Ontario, and the state of Washington. Telvent's technology will enable increased system security, and will be compatible with existing systems from other providers, implying lower operating costs for electric company.
     OASyS DNA technology provides the means of combining Telvent's products and services with those of its customers, partners, and competitors, to provide a tailored solution that meets the end user's needs. This technology provides the ability to blend existing tools, new custom applications, and SCADA so that RealTime data may be fed into day-to-day operations, business and planning activities efficiently.

Varion Systems, the software development and value-added reseller division of GeoAnalytics, has completed a public deployment of PV.Web for the City of Wheaton, Illinois. Through the city's website, Wheaton residents can now view city data and mapping functionality on their own computers via PV.Web.
     In conjunction with ESRI's ArcIMS and ArcSDE, PV.Web allows Wheaton residents to view several GIS layers — including registered sex offenders, police beats, schools, zoning areas, parcels, addresses, public works data, sewer data, engineering data, planning data, transportation data, trails and paths data, and aerial photography.

The City of Philadelphia's Streets Department has implemented Cityworks, from Azteca Systems, a provider of GIS-centric asset maintenance management solutions. Philadelphia Streets implemented Cityworks using a methodical system, targeting specific groups one at a time. This mitigated many challenges often associated when in-house staff is used to implement a new management system. It also allowed the implementation team the opportunity to ensure Cityworks fit the workflow processes of a wide variety of groups within the department.
     The implementation was led by Marion Storey, Information Technology Application Program Manager for the City of Philadelphia Streets Department. The effort began with remote training and familiarization for Ms. Storey and her team. They deployed Cityworks to the Concrete Operations, Alley Lighting, and Right of Way Units, and are looking to expand the system into the Survey Bureau.

Pictometry International Corp., a provider of digital, aerial oblique imagery and measuring software, has announced that its European partner, Blom ASA of Norway, through its subsidiary Simmons Aerofilms, has signed a contract with Ordnance Survey of Great Britain. The agreement establishes Ordnance Survey, Britain's national mapping agency, as the sole sales agent of Pictometry technology for its customers in government and private industry in Great Britain. Simmons Aerofilms will be capturing and processing the high-resolution aerial images and supplying Ordnance Survey customers with the image libraries together with training.

When the new MTSAT-2 meteorological satellite launched from Tanegashima Space Center in Japan on February 18, a five-channel imager manufactured by ITT's Space Systems Division was aboard. ITT built the Imager for Mitsubishi Electric Corporation, the prime contractor for MTSAT-2. The satellite, which was launched into geostationary orbit 22,000 miles above the Earth's equator, is owned by Japan's Ministry of Land, Infrastructure, and Transport. The ITT imager will allow MTSAT-2 to obtain cloud imagery to provide better meteorological services in East Asia and the Western Pacific. The information will be used to improve weather forecasts, mitigate natural disasters, and help secure safe transportation.


Snowflake Software's GO Publisher WFS product has passed all compliance testing with the Open Geospatial Consortium (OGC). This makes the company one of seven that have met the compliance testing for the OpenGIS Web Feature Service Implementation Specification, Version 1.0. GO Publisher v 1.2 is the first release of the GO Publisher product suite to include the WFS features and was released last month.
     GO Publisher WFS is a Translating Web Feature Server that provides real time on-demand data access via the Web through ISO and OGC standards. Utilizing the same graphical configuration interface as GO Publisher Desktop, GO Publisher WFS provides an easy migration path to enterprise Web publishing by reusing all setup and configuration options available in the desktop version. As a Translating Web Feature Server, GO Publisher WFS plays an integral part in the proposed infrastructure for country-wide, European, and international legislation demanding the availability and sharing of data across government bodies and organizations. The SDI infrastructure is a prime concern in allowing organizations to better address social, economic, and environmental issues of critical importance.
     The GO Publisher product suite generates XML from all standard databases - Oracle, SQL Server, DB2, MS Access, Excel, and any other JDBC-compliant datastore and has been successfully applied to a variety of schemas, including but not limited to: BS7666 XML, CityGML, EuroRoads, GOSTP, KML, NAS, OKSTRA, OS MasterMap.

Tensing USA has released its SPY .NET suite of mobile products, the first mobile GIS solution that is entirely based on the Microsoft .Net Framework. This platform-independent suite will run on any Windows-driven device that utilizes the .NET Framework 2.0 or .NET Compact Framework 2.0. Tensing developed the SPY .NET suite, built on the core SPY technology, specifically for end users who do not need a full-blown GIS but require fast-performing field tools and hardware independence. The SPY .NET suite consists of Tensing SPY Mobile GIS, Tensing SPY Development Suite, Tensing Live Connect, and Tensing Gateway.
     Tensing SPY Mobile GIS allows field staff to review, analyze, and change data in the field. It extends GIS capabilities to crews in the field and gives them access to entire mapping systems on laptop, pen, tablet computers, and PDAs. Data is provided to the crews by extracting it from any corporate GIS database via a one-to-one conversion tool that simplifies the presentation of the data. Tensing SPY Mobile GIS now allows the customer to define the same application regardless of hardware platform.
     Tensing SPY Development Studio is a set of tools that the developer can access in a Visual Studio environment. It allows clients to create additional functionality for field users without requiring assistance from the vendor.
     Tensing Live Connect integrates with any dispatching system to extract data related to a specific work order. The utility does not have to worry about security, compression, administration, or even practical issues as this solution resolves all of those issues today. Via Tensing Live Connect, GIS data is provided on a real-time basis and can be supplemented using Web services to obtain any back office system data.
     The fourth component, Tensing Gateway, offers a direct approach to ensuring the transfer of data from a Smallworld GIS into the field. This extractor runs within Smallworld and allows utility and telecom customers to convert their geospatial data for use in a mobile GIS application. Tensing Gateway transfers the data between Smallworld and Tensing SPY Mobile GIS for rapid access, use and QA/QC before data updates made in the field are returned into the Smallworld GIS repository.

MapInfo Corporation, a provider of location intelligence solutions, has introduced Envinsa Version 4.0, a unified location platform that enables organizations to centrally manage location analysis capabilities and apply them throughout the organization. The product includes a host of new location intelligence capabilities designed to provide deeper insight into data.
     Envinsa v4.0 also supports new data sources, such as Oracle 10g, and features expanded support for interoperability standards, such as the Open Geospatial Consortium specifications, including certification for Web Mapping Service 1.1.1. In addition, Envinsa v4.0 provides access to network-generated location data from the Sprint PCS Business Mobility Framework, enabling organizations to provide improved field force management using real-time location intelligence. Due to its Web services interface, Envinsa v4.0 provides developers with the flexibility to integrate location intelligence into Web applications.

SoftMap is offering to the GIS industry more than 13,000 Canadian topo maps in GeoTIFF format (DRG) ready to be downloaded on request and at a new low price. SoftMap GeoTIFFTM is a raster map at the 1:50,000 or 1:250,000 scale published by Natural Resources Canada (NRC) and scanned. The collar has been removed to facilitate seamless navigation. The maps are downloadable in a zip file via FTP protocol.
     Topographic maps produced by NRC conform to the National Topographic System (NTS) of Canada, which provides general-purpose topographic map coverage of the entire Canadian landmass. These maps depict, in detail, ground relief, drainage, forest cover, administrative areas, populated areas, transportation routes and facilities, and cultural features. They are available in two standard scales, 1/50,000 and 1/250,000.
     The maps show a geographic grid (longitude and latitude) and a Universal Transverse Mercator (UTM) grid (kilometres). The area covered by a given map sheet is determined by its latitude and longitude. Since the NTS uses a standard numbering system, knowing the map number allows you to quickly identify adjacent map sheets. Under the NTS, Canada is divided into quadrants that vary in size depending on dataset (or map) scale and latitude.
     All provinces and territories are now available: Newfoundland and Labrador, Prince-Edward-Island, Nova Scotia, New Brunswick, Quebec, Ontario, Manitoba, Saskatchewan, Alberta, British Columbia, Yukon, North West Territories, and Nunavut (partially).
     The file format is a Packbits compressed TIFF, 254 dpi, 256 colors (8 bits). The georeference file formats are TIFF (GeoTIFF), TAB (Map Info) and TFW (World File). The numerical files are georeferenced in UTM NAD83. The map sheets created in NAD27 have been converted to NAD83 with great precision using NTV2 conversion table. A metadata is file included.

The GRASS Development Team has released GRASS GIS v. 6.0.2, a bugfix release. The Geographic Resources Analysis Support System, commonly referred to as GRASS GIS, is used for data management, image processing, graphics production, spatial modeling, and visualization of raster, vector, and sites data. It is open source free software released under the GNU General Public License (GPL).
     The new features of GRASS 6 cover a new topological 2D/3D vector engine and support for vector network analysis. Attributes are now managed in a SQL-based DBMS. A new display manager has been implemented. The NVIZ visualization tool was enhanced to display 3D vector data and voxel volumes. Messages are partially translated (i18N) with support for FreeType fonts, including multibyte Asian characters. New LOCATIONs can be auto-generated by EPSG code number. GRASS is integrated with GDAL/OGR libraries to support an extensive range of raster and vector formats, including OGC-conformal Simple Features. For details and a list of bugfixes, see the full announcement.
     GRASS is a founding member of the new Open Source Geospatial Foundation. GRASS supports the following platforms: GNU/Linux, Sun Solaris (SPARC/Intel), Silicon Graphics Irix, Mac OS, X/Darwin, Microsoft Windows with Cygwin, HP-UX, DEC-Alpha, AIX, BSD, iPAQ/Linux and other UNIX-compliant platforms (32/64bit). The new source code is available now, and selected binary distributions for major operating systems will be published shortly.

DeLorme, a provider of mapping, GIS, and GPS solutions, has released one-meter resolution aerial imagery for the state of Florida. Processed into DeLorme's XMap format, this imagery is available in a series of twelve seamless mosaics, each of which provides regional coverage on a single DVD or statewide coverage on a USB hard drive. Now it's possible to bring high-quality aerial imagery into the field without the need to download and manage dozens of individual files or to be connected to the Internet.
     Derived from Florida's DOQQ data files, this imagery was captured in 2004 and 2005 and represents the most up-to-date and complete aerial imagery that is currently available for the entire state. In conjunction with XMap, this dataset is ideally suited for utility workers, insurance adjusters, realtors, first responders, law enforcement officers, and anyone who appreciates the value of high-quality aerial imagery and a mapping application while in the field. DeLorme plans to release additional sets of XMap formatted state imagery over the next year.


Remains of the ancient Maya culture, mysteriously destroyed at the height of its reign in the ninth century, have been hidden in the rainforests of Central America for more than 1,000 years. Now, NASA and university scientists are using space- and aircraft-based remote-sensing technology to uncover those ruins, using the chemical signature of the civilization's ancient building materials.
     NASA archaeologist Tom Sever and scientist Dan Irwin, both from NASA's Marshall Space Flight Center in Huntsville, Alabama, are teaming with William Saturno, an archaeologist at the University of New Hampshire in Durham, to locate the ruins of the ancient culture. Sever has explored the capacity of remote-sensing to serve archaeology. He and Irwin provided Saturno with high-resolution commercial satellite images of the rainforest, and collected data from NASA's Airborne Synthetic Aperture Radar (SAR), an instrument flown aboard a high-altitude weather plane, capable of penetrating clouds, snow, and forest canopies. These resulting Earth observations have helped the team survey an uncharted region around San Bartolo, Guatemala. They discovered a correlation between the spectral signature of the vegetation seen in the images and the location of known archaeological sites.
     In 2004, the team ground-tested the data. Hiking deep into the jungle to locations guided by the satellite images, they uncovered a series of Maya settlements exactly where the technology had predicted they would be found. The cause of the floral discoloration discerned in the imagery quickly became clear to the team. The Maya built their cities and towns with excavated limestone and lime plasters. As these structures crumbled, the lack of moisture and nutritional elements inside the ruins kept some plant species at bay, while others were discolored or killed off altogether as disintegrating plaster changed the chemical content of the soil around each structure.
     Under a NASA Space Act Agreement with the University of New Hampshire, the science team will visit Guatemala annually through 2009, with the support of the Guatemalan Institute of Anthropology and History and the Department of Pre-Hispanic Monuments. The team will verify their research and continue refining their remote sensing tools to more easily lead explorers to other ancient ruins and conduct Earth science research in the region.
     Scientists believe the Maya fell prey to several cataclysmic environmental problems, including deforestation and drought, that led to their downfall, Irwin said. Another aspect of the research involved using climate models to determine the effects of Maya-driven deforestation on ancient Mesoamerican climate. The goal of this effort was to determine whether deforestation can lead to droughts and whether the activities of the ancient Maya drove the environmental changes that undermined their civilization.
     Extending benefits of remote-sensing technologies is part of NASA's Earth-Sun System Division. NASA is conducting a long-term research effort to learn how natural and human-induced changes affect the global environment, and to provide critical benefits to society today. Sever and Irwin conduct research at the National Space Science and Technology Center in Huntsville, a joint science venture between NASA's Marshall Center, Alabama universities, industry, and federal agencies.

General Colin Powell, USA (Ret.), will be the featured keynote speaker for Intergraph 2006, Intergraph Corporation's international users conference, to be held June 12-15 in Lake Buena Vista, Florida, at Disney's Coronado Springs Resort.
     General Powell became the 65th Secretary of State of the United States of America in 2001 under President George W. Bush and retired from that post last year. Previously, Powell served as a key aide to the Secretary of Defense and as National Security Advisor to President Reagan. He also served 35 years in the United States Army, rising to the rank of Four-Star General and serving as Chairman of the Joint Chiefs of Staff (1989 to 1993). During this time he oversaw 28 crises, including the Panama intervention of 1989 and Operation Desert Storm in the 1991 Persian Gulf War.
     Born in New York City, General Powell earned a bachelor's degree in geology from the City College of New York (CCNY) where he participated in ROTC. Upon graduation he received a commission as an Army second lieutenant. He later earned a Master of Business Administration degree from George Washington University. General Powell is also the recipient of numerous U.S. military and civilian awards and decorations, as well as international honors, including the Purple Heart, two Presidential Medals of Freedom, and an honorary knighthood bestowed by H. M. Queen Elizabeth II of Great Britain.

GlobeXplorer has announced the latest functionality addition to its ImageAtlas aerial/satellite/map viewer: the ability to instantly pick, compare, and purchase images from multiple dates. Users simply zoom to their area of interest and then click on a pull-down menu to select from all of the versions of imagery GlobeXplorer carries at that location and zoom level. Multi-date picking gives ImageAtlas users full access to GlobeXplorer's catalog of imagery spanning back 15 years, and, in some areas, much further.
     Users now have the ability to instantly select a version with the date, color balance, and resolution that best suits their needs, and see change in their areas of interest over time. Up to 12 different image versions can be accessed in many major metropolitan areas, dating back to the early 1990s. Users can instantly purchase large digital files and prints of the images, and subscribers have the ability to right-click and copy unwatermarked images directly from the viewer.

Hundreds of vivid illustrations and real-world examples merge in Remote Sensing for GIS Managers, a new book from ESRI Press that reveals the power of interpreting information gathered from aerial photography, radar, satellite, and other remote-sensing methods. Readers will travel from the vast ocean depths to the far reaches of outer space as they learn everything from the basics of remote sensing to the challenges of interpreting, managing, and storing the ever-increasing range of remotely sensed data available today. Designed for both new and experienced users, Remote Sensing for GIS Managers is invaluable for GIS managers, professionals, and students who want to become more knowledgeable users of remote-sensing services and manage the development of innovative solutions suited to the needs and goals of their organizations. The book's case studies illustrate the use of remote sensing in national security, urban and regional planning, resource inventory and management, and scientific disciplines ranging from forestry and geology to archaeology and meteorology.
     A seasoned writer and professional, author Stan Aronoff wrote the classic and still widely used GIS text Geographic Information Systems: A Management Perspective and coauthored the award-winning book Total Workplace Performance: Rethinking the Office Environment. Aronoff's career includes the development of software and procedures for integrated analysis of remotely sensed and GIS data.
     Remote Sensing for GIS Managers (ISBN 1-58948-081-3, 524 pages) is available in bookstores and from online retailers worldwide or can be purchased on-line.

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