Setting new boundaries
- By Dan Carney
- Oct 16, 2000
Geographic information systems may be the government's favorite computerapplication. GIS can map resources, count the population and plot plannedimprovements. But, historically, GIS applications have run in tightly controlledenvironments on desktop PCs and workstations.
But now GIS applications are getting out of the office, venturing afieldto directly record information using handheld computers and wireless communicationsto instantly update bodies of knowledge. And those same GIS applications,whose information was once only accessible by the privileged few GIS specialists,are now accessible to interested parties from all over the world via theWorld Wide Web.
"The impact is better communication with the constituency, whether thatis other government agencies or citizens," said Joel Campbell, regionalmanager of Environmental Systems Research Institute Inc.'s Washington office."They don't have to call up [the Federal Emergency Management Agency] andtalk to five different people to get the information they need. They canjust go to the Web site. It makes access to the data easier for John Q.Public."
Not only are online maps more accessible to a wide range of users, theyare more interactive. For example, the National Cancer Institute's cancermortality map originally was contained in a book of statistics on cancerdeaths in each part of the country. Obviously, the maps in the book werestatic and could not be changed by a reader wanting to dig deeper into thedata.
Likewise, the initial Web posting of the book simply showed images ofthe static maps in the book. But the new, interactive map based on MapInfoCorp.'s Map Extreme technology lets viewers decide how to show the information.Instead of showing the differences in cancer mortality in increments of10 percent, viewers can change that to whatever size increments they need.
"Using Map Extreme, I can break that down any way I want to," said DanGrauman, computer specialist at the NCI, which is part of the National Institutesof Health. Users could choose to display only the states or counties withthe very highest cancer mortality rates, for example. "If I want to seethe top 5 percent and just show that, I can do that," he said.
But GIS applications aren't limited to desktop PCs once they are puton the Web. Handheld PCs can also access GIS applications and can serveto both retrieve and enter information.
"This is one of the really hot topics in the industry right now," saidDavid Sonnen, senior consultant for spatial information management at InternationalData Corp. "The ability to access enterprise data from a handheld and interactwith that data is significant."
Having agents enter data collected in the field directly into the computerdatabase provides the opportunity for more and better information to berecorded, reduces the chance of errors being introduced, saves time becausethe data doesn't need to be keyed in from paper reports and makes the reportsavailable in a more timely fashion.
"The benefit of this approach is that it eliminates several steps,"Sonnen said. "They've shortened the process by two or three people and hoursof labor," which will save federal agencies money, he added.
"There is a reduction in administrative costs and, in theory, an improvementin the accuracy of the data," Campbell said.
One question for federal agencies fielding handheld-based GIS applicationsis whether those devices need a persistent connection to the database orwhether they can roam disconnected and then plug in at the end of the dayto share data. The decision depends on the nature of the application andon the means of wireless communication used.
An application designed to provide real-time updates of tactical battlefielddata requires a constant connection to the server, while a census-takingapplication can probably work just as well if it connects only once a day.
The Army has its own radio communications network to keep in contactwith handheld devices, making it easy to maintain constant communications."For the agencies that own their own communication network, this is inexpensive,but for those that don't, it is very expensive," Sonnen said.
Another shortcoming with wireless communication is a dearth of bandwidth,which is needed for moving data-heavy images to the portable devices. Varioussolutions are available to address the problem, including transmitting onlynew, changed data rather than the entire map when updating. "They don'tmove the whole map, they just move the parts that change," Sonnen said.
That is the approach used by Argonne National Laboratory's Dynamic ObjectOriented GIS site, which displays map data.
"We don't send everything over," said Gordon Laurie, a software engineerat the lab. "There is a representation that is sent over that is not thefull amount of the data," he said. "More detail is available by drillingdown into the representation. This is possible because the map is interactiverather than static."
The Argonne lab developed its own object-oriented GIS system, Geoviewer,which it uses for its Web-based GIS applications.
Another option for saving bandwidth is image-compression technology,which makes images easier to download. Xippix Inc. has developed an image-managementtool called Image Pump, which lets agencies post interactive maps on theInternet using relatively little bandwidth, for faster loading.
It is important for maps to be dynamic, letting users zoom in on thedetails that interest them, because they tend to cover large areas of territorythat aren't of interest. "We've found that a lot of our customers have somevery large images, but in those images there are only a few interestingthings to look at," said Jeff Guns, vice president of product marketingfor Xippix.
Ultimately, faster digital cellular data transmission speeds will beavailable, but widespread deployment of such systems is at least severalyears off, Sonnen said.
Also helping agencies extend GIS applications beyond their traditionalboundaries is the trend toward GIS solutions that use more industry-standardcomponents, such as databases and programming tools. Those have historicallybeen proprietary systems, written specifically by the GIS application softwarevendor for use with its application.
Database vendors such as IBM Corp., Informix Corp., Oracle Corp. andMicrosoft Corp. have made or are making their products more suitable foruse with GIS applications by adding spatial data formats to their traditionalformats.
"A lot of people want to store all of their data in a single database,be it spatial data or tabular data," said Dan Ahern, senior marketing managerat AutoDesk Inc. "It is an opportunity for GIS to become mainstream."
That is exactly what the Environmental Protection Agency is doing withits ESRI GIS and Oracle database, said Dave Wolf, Internet geoservices managerin the EPA's office of environmental information.
"We had to reprocess our old ESRI database into an Oracle spatial database,"Wolf said. "Now we have corporate data and geospatial data in the same databaseinstance."
"Mainstream databases have embraced spatial as a data type," said StevenCooperman, director of spatial and wireless solutions in Oracle's serviceindustries group. "The existing users of spatial information are movingfrom proprietary databases, and they are consolidating that informationinto a central database."
Using popular data types also makes it easier for agencies to sharedata, according to Wolf. "This is the way we deliver our geospatial informationand the way we exchange services with other federal and state agencies,"he said. "We don't anticipate maintaining an entire [separate] geospatialdatabase."
Making GIS applications available to a wider audience helps people outsidethe GIS community understand the value of their work, said Jeff Cotter,program manager in the Justice Department's Justice Management Division.
"When people aren't used to seeing their data displayed geographically,you sometimes have to sell them on it with a pilot program," Cotter said."Then the strength of the application sells itself. People are incrediblyimpressed."
Carney is a freelance writer based in Herndon, Va.