Coupling cartography with computers

Geographic Information Systems used to be pricey software packages backed by huge data bases, of interest only to mapping agencies. Not any more. Anand Parthasarathy reports on the emerging role of GIS as a mass consumer tool marrying the Internet to satellite technology.

A RECENT edition of the ``Oprah Winfrey Show'', telecast over India, in the Star World satellite channel, featured an American housewife who confessed to an unusual malady: she could never find her way to an unknown address. Maps, street signs - they all scared and confused her. Try, once more, with a newly launched product fitted in your car, Oprah suggested.

A filmed clipping showed the woman driving in a strange town and seeking an unknown address. Her car now had been fitted with the latest model of the ``Magellan'' voice-assisted satellite navigation computer, manufactured by the New Jersey-based VIT Electronics. The driver speaks into a mike reading out the address she is seeking.

The satellite receiver of the Magellan system, establishes the present position of the car by interrogating the nearest satellite of the Global Positioning System (GPS) - then brings up the location on a coloured map on the Liquid crystal display. Simultaneously a friendly synthesized voice, guides the drives even as a marker on the display follows the car's movements ``You are now at the corner of 22nd Street and Maple drive... take the next turning to your right....go past the traffic lights and turn into Woods Hole Avenue....''.

Finally the voice signals that the driver has reached journey's end ``

The address you wanted should be the next block on your left!'' The woman confessed this was the first time she had ever found an address without having to ask dozens of strangers at every turn. Car and personal navigation devices like these are the hottest new computer appliances on sale in 2000 - and prices of units range from $ 200 - $ 400.

Only a few years ago, a GPS-backed navigation system like the ``TrimPack'' from Trimble Electronics, that US marines used in the Gulf War to find their bearings in hostile territory, would have set one back at least $ 1000.

But the moment canny developers discovered the lucrative niche of car navigation, the whole science and art of Geographical Information Systems (GIS) reinvented itself.

Hitherto a costly tool used largely by cartographers, demographers and planners, GIS has today become an affordable consumer tool - a development which is slated to open up the entire field to the cool new breeze of innovation.

Classical GIS is less than 40 years old: the first applications - where spatial information available on maps was digitised and stored in large relational data bases (RDBMS) to be processed by number-crunching computers which fed high resolution printers - originated in the US where national agencies monitoring land and water use were faced with godowns full of mapped information and no means to access the valuable data they contained.

Indeed, the components of a typical GIS (see diagram) remain largely unchanged even today: a workstation backed by a large computer; devices to digitise analog information, like scanners and digitizer tablets; devices to produce fresh outputs like high resolution printers, large databases of geographical and image data and the software to operate all these elements and store the newly digitised information in an easily retrievable form.

What has evolved in the subsequent decades is a better appreciation of how to go about the business of creating a data bank of geographic information that can be manipulated and exploited, in the most efficient way possible.

GIS developers have tended to chop up maps into different ``objects'' for easy handling - a ``point'' could represent a place: a building, hotel etc; a network or ``chain'' could represent roads, rivers or railway tracks; ``nodes'' could be intersections or traffic junctions.

Objects could be further described by their ``attributes'' - type of bridge; size of lake - specifying ``class'' of attribute (overbridges; schools) or ``value'' of attributes ( number of overbridges or students in school). By thus breaking up elements of a map into separate entities, scientists succeeded in digitally extracting its content. But what was the best way to organise all this information? Was it a large RDBMS? Was it an ``Object oriented'' data base? Or - as a recent doctoral work undertaken in GIS at the Cochin University of Science and Technology (CUSAT) suggests - is it time to create a ``knowledge based'' GIS, with elements of the ``expert system'' that Artificial Intelligence (AI) workers are so fond of? Dr. P. Jayaprakash who worked with Dr. A. K. Menon on this project tried out a pilot scheme of a ``Knowledge-based GIS'', digitising all the information he could obtain for one city - Thiruvananthapuram.

Using a MicroVax-II work station ( the system can be ported with a little effort, on any contemporary Unix or NT workstation), Jayaprakash created a system which bears out his contention that a ``knowledgeable'' approach provides superior query and search capability.

The core of his architecture is a spatial object knowledge base, working in tandem with a ``rule'' base. Searches are carried out simultaneously at high ( or object) level and a low (or graphic element level).

A query like ``Display all the roads in Thiruvananthapuram intersected by the river Karamana'' or ``Display all the vegetarian hotel within 2 kms of the railway station'', illustrates the power of this approach over what would have been an extended search of a bulky RDBMS.

The work is limited only by the maps available to the general public in India: Jayaprakash digitised maps of the city of the scale 1: 20,000. Indeed one of the problems facing any one in India who ventures into GIS is the pathetic availability of maps to a practical scale. Archaic laws have placed most high resolution maps available with the Survey of India, in the restricted category: a policy which needs to be revised, considering that much more detail can be obtained by any one who can pay for printouts of satellite imagery obtainable from dozens of agencies worldwide.

Meanwhile, using available resources from the Survey of India as well as the National Remote Sensing Agency (NRSA), some enterprising Indian developers have begun to broaden the scope of GIS:

- The Visakhapatnam-based Spatial Technologies has developed a Web-based GIS for decision support systems and started to put data for 27,000 Andhra revenue village units into a ``Spatial Web Andhra'' database. They hoped to extend the scheme to the whole country.

- Hindusthan Office Products Ltd (HOPE) has joined hands with the Maharashtra State Electricity Board (MSEB) in a pilot scheme to create a Network Information Management System (NIMS) for Aurangabad zone, providing information about the entire grid network in the area, optimal placement of components, resource utilisation and financial management.

- Researchers at the Tata Energy Research Institute (TERI) are working on what they call a ``triangulated irregular network'' (TIN) to build three dimensional model maps to highlight crucial geographic and environmental information.

TERI used the technique to study the environmental stress on the Yamuna as it flows through five northern states; and the effect of iron ore mining on land use patterns in Goa.

The Mumbai-based ``Computer Eyes'', has created the most detailed map profile ever, of the city, called ``Mumbai Pathfinder''.It is available as a printed book or a CD and is based on satellite imagery over the metro, integrated with a GPS position finder. Computer Eyes hopes to extend the project to 300 other Indian cities.

To help such efforts, a few well known international GIS products are available - and almost all of them are represented in India. Among the better known are MapInfo (from Tata Infotech) and AutoDesk from the group that makes the well known AutoCad software; Intergraph from Rolta and ESRI supported by NIIT. Their products range on price from Rs. 50,000 to Rs. 20 lakhs or more. Their market is still restricted to a small coterie of developers in the country. The ``killer application'' for the mass market will come when someone uses these tools to create an India- specific navigation system - then marries it to some affordable GPS-based hardware.

This is not an unlikely scenario - because in recent weeks, the whole business of personal navigators has expanded another notch: since early 2000, map information downloadable from the Internet is being offered on the latest models of well known mobile phones. The French telecom giant, Alcatel teamed up with Webraska Mobile Technologies of the U.S. to offer what is claimed to be the world's first real time traffic information mapping system.

At the World GSM Congress of cell phone makers, in Cannes, France, last month, they demonstrated an Alcatel cellular phone, which could - via the Internet - display 26 different maps in an around Paris, updated in realtime with traffic conditions information. Other Japanese makers like Panasonic also offer hand-held and phone-based map displays which can be used by tourists and business visitors to help find their way in foreign cities, and locate places like hotels, restaurants and hospitals.

These devices are likely to further bring down the cost to the customer of accessing digitised cartographic information, while ``on the hoof''. Mobile phone models available in India are contemporary with what's available in most other countries - so clearly hardware is not a problem.

But GIS content? This requires government will rather than mere investment. Some one, somewhere in India's IT corridors of power must have the guts to say: Let's not deny to our own people the detailed knowledge about their country that any one abroad can buy for a few dollars by whistling up the right satellite. The prying eyes in the sky cannot be turned off. So let's accept this new fact of strategic life and give our people the spin off benefits of this same technology, to go from here to there with ease.

Shubha yaatra - GIS ke saath!

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