FÖLDRAJZI PONTOSSÁG A WORLD4ALL.INFO-VAL

Informatika a Felsőoktatásban 2002

Debrecen, 2002. augusztus 28-30.

FÖLDRAJZI PONTOSSÁG A WORLD4ALL.INFO-VAL GEOGRAPHICAL ACCURACY WITH WORLD4ALL.INFO Schleusener Heinz, [email protected] Nagy Elemerne, [email protected] Plewka Thomas, [email protected] TU Berlin, School of Process Sciences and Engineering University of Szeged, Szeged College of Food Industry rationet Informationssystem GmbH Berlin Abstract If one wants to explore geographical regions using the internet, link lists are often received as a result. Yet where are the small towns and villages situated? It was indeed an odyssey to obtain an answer to this question. A new web site, World4all.info, offers an innovative solution based on GPS data, a solution that offers perfect help to desperate researchers. The interactive WWW-solution World4all.info permits searches for geographically related information in the simplest way possible. A search will find every website containing the GPS coordinates of the enterprise or institution concerned in a meta tag of the HTML home page, or every site with GPS data registered in a World4all.info data base. The owners of a domain are free to document their location unmistakably with their own distinctive icon on the map. Using World4all.info, a researcher can fully explore a geographical region, list sites of interest, examine locations on a map, determine distances, and request further information from a selected web site without closing a particular map. The program thus provides quick and accurate solutions for many research problems dependent on geographical information.

Összefoglalás Ha valaki földrajzi területeket szeretne megtalálni az Interneten, gyakran hivatkozáslistákat kap eredményül. De hol találhatók a kisvárosok és a falvak? E kérdés megválaszolása különösen nehéz volt. Egy új webhely, a GPS adaton alapuló a World4all.info, innovatív megoldást kínál erre: egy megoldást, ami tökéletes megoldást nyújt a kitartó kereső számára. Az interaktív, WWW-n alapuló World4all.info a lehető legegyszerűbb módon nyújt a keresők számára földrajzzal kapcsolatos információkat. A keresés eredménye minden olyan Webhely, ami a kérdéses vállalat vagy szervezet GPS koordinátáit tartalmazza a HTML honlap egy „Meta-Tag”-jában, illetve minden olyan hely, amelynek GPS adatát a World4all.info adatbázisában regisztrálták. A domain tulajdonosok egyéni ikonjukkal félreérthetetlenül megjelölhetik helyüket a térképen. A World4all.info használatával a kereső teljesen feltárhat egy földrajzi területet, kilistázhat érdekes helyeket, megvizsgálhat helyszíneket a térképen, meghatározhat távolságokat és további információt kérhet egy adott Webhelyről anélkül, hogy bezárna egy adott térképet. A program így gyors és pontos megoldást kínál földrajzi információn alapuló keresési problémákra. Összegezve: a WORLD4ALL.INFO-t azzal a filozófiával fejlesztettük ki, hogy összekapcsoljuk a földrajzi helyeket és honlapok hivatkozásait. Nem az a célunk, hogy valamennyi létező honlapot és területet felvegyünk az adatbázisba. E megoldás által nyújtott lehetőségeket csak meghatározott területeken tervezzük használni. Ez például új lökést adhat az utazás és a szabadság Internet használatával történő megtervezéséhez – ami egy lényeges érv, különösen olyan országok számára, mint Magyarország.

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FÖLDRAJZI PONTOSSÁG A WORLD4ALL.INFO-VAL GEOGRAPHICAL ACCURACY WITH WORLD4ALL.INFO Schleusener Heinz, [email protected] Nagy Elemerne, [email protected] Plewka Thomas, [email protected] TU Berlin, School of Process Sciences and Engineering University of Szeged, Szeged College of Food Industry rationet Informationssystem GmbH Berlin 1. Introduction Existing search engines and GIS readily accessible via the INTERNET are failing due to the fact that they are becoming increasingly difficult to use when people want to find out more about hotels, ski lifts, chair lifts, swimming pools (and the distances between them), and about other attractions in the areas they plan to visit. Search engines show their results in tables, only without any geographical references. WORLD4ALL.INFO is a true breakthrough, with its innovative features based on GPS and its presenting maps on an entirely new and more accurate scale. It uses information that can be stored in special "Meta Tags" on the web site, gives directions to where it is that a person may want to go, and it describes the geographic coordinates of places of interest. Other data, in addition to the data just mentioned, will be stored on the web site's database. Simply put, searching for graphic references will become very simple and, above all, extremely precise. By using World4all.info, a person can find every web site containing the GPS coordinates of the company, institution, hotel, and restaurant in one Meta-Tag of the HTML data or in those stored in the database of WORLD4ALL.INFO. Owners of one domain are free to interchange their place on the map with their own icon. They do not have to book with various map providers any more in order to be found on the Internet. WORLD4ALL.INFO brings simplification to the searcher also. Now he or she can find geographic regions, can have places shown on the map, and can list corresponding homepages, get distances among various points, ask about other attractions in the area, and use direct links to the corresponding web site without having to close or leave the chosen map.

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2. The Meta Tag WGS84 We will not concern ourselves here too much with the meaning of meta tags. Meta tags can be written in the header of a HTML document, and they are useful for giving instructions to WWW servers, WWW browsers, and automatic search programs (robots). Furthermore, a meta tag can be used to describe the name of the author and the content. Unfortunately, there is no standard for meta tags, only recommendations from the WWW consortium. There is no doubt that meta tags in the future will be indicating geographic positions and will have to consider existing solutions in geopositioning like GPS. GPS works with WGS84coordinates. That’s the basic for our proposal. We recommend using that coordinate system and defining a meta tag for a geographic position in syntax (1). We call that proposed tag “WGS84 Geo Meta Tag”. <META NAME = ”WGS84” CONTENT = ”g, m, s, lat, g, m, s, lon [, alt, gf, lay, p]” (1) with - g = degree, m = minutes, s = second (decimal); - lat = latitude (north or south); - lon = longitude (east or west), - alt = altitude; - gf = geometric figure{r=radius, l=line, re=rectangle, p=polygon}; - lay = layout{ f=filled, t=transparent, l=normal line, lp=dotted line, ls=stripped line, c=color}; - p = set of parameters for gf.

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Example (coordinates of the town Debrecen): <META NAME=”WGS84” CONTENT=”46, 32, 00, N, 21, 38, 00, E”>

(2)

3. Function principle of WORLD4ALL.INFO WORLD4ALL.INFO is based on one database, which besides other features consists of accessible maps and data of the stored companies or institutions. The database is built from two data tables, one of which contains information about maps. The data fields hold the names of maps, the names of map files, information about scale, the coordinates of the point in the bottom left corner, and the coordinates of the other point in the top right corner. All maps have the pixel size 640 x 480. The maps are displayed on the right side of the browser window. Preferably, the graphics format GIF is used. The second table consists of information that includes the geographical coordinates of companies or institutions, along with the companies' web addresses. Therefore, it contains the name of the site, its URL, and its geographic position. Additional fields, like mail address, telephone and fax number, and e-mail address complete the structure. Maps correspond to those of GPS based on the coordinate system WGS84. A screen resolution of 1024*768 pixels is recommended for optimal display viewing. 4. Navigation As opposed to other solutions, WORLD4ALL.INFO offers a special method of navigation. There is no zoom function but a dialog exists between the map (right side of the display) and the map selection window (left side). The map selection window shows all maps which are available for a chosen point (coordinates), ordered by scale. Each clicking at a point results in the detailed map available in the data base. The map selection window can be used for changing to a larger or another map. To find places like hotels or restaurants, a search term needs to be typed into the search window. After submitting the search term by hitting the ENTER key or the graphic symbol , the search function is started and activated. Hits will be shown either with a standard symbol or with the logo of the enterprise. There are two standard symbols that depend on the precision of the coordinates: GPS precision (indicated by a cross) and rough precision (indicated by a circle). On every map chosen by the mouse, a person can look for objects of interest, such as places with swimming opportunities, ski lifts, rental stores, hotels, restaurants, theaters, and so on. The chosen web sites can be listed in a table and are directly accessible from the table or the map. Future versions will be able to search for objects in a region indicated by the mouse cursors directly in the map.

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5. How to subscribe Unfortunately, most web sites don’t contain the new WGS84 meta tag yet. To be included in the WORLD4ALL.INFO database, it is necessary to send the coordinates of your particular web site to our administrator. WORLD4ALL.INFO offers a special input window for users with interest in taking part in the database. 6. Summary To summarize, we have seen that the philosophy of WORLD4ALL.INFO was developed to join geographical positions and links to web sites. Our goal is not to expand the database for all existing web sites and areas. We plan to use the possibilities of this solution for specified regions. This will give people new reasons to use the Internet, such as to make travel plans and to make holiday arrangements, and this would greatly benefit a country like Hungary.

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FÖLDRAJZI PONTOSSÁG A WORLD4ALL.INFO-VAL

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