A GIS APPLICATION OF AN OTTOMAN CEMETERY ON DARDANALLES OVER INTERNET. Guney, C., Celik, R. N.

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1 A GIS APPLICATION OF AN OTTOMAN CEMETERY ON DARDANALLES OVER INTERNET Guney, C., Celik, R. N. Abstract Access to spatial data and interactive database applications with querying capabilities over the internet is growing rapidly. The current paradigm shift involves the migration of application software from individual desktop computers into an internet-based client/server architecture. As a result, it is seen large-scale development of Geographic Information System (GIS) applications that can be accessed by the user through a web browser interface. This paper describes the development of a web-based GIS system as a component of a major web application of Historical Documentation Project of Seddülbahir and Kumkale Fortresses on Dardanelles. INTRODUCTION The cultural heritage is the most important evidences regarding the past society and each object of these has valuable information about the past. Unfortunately each valuable element of the historical structures has been vanishing day by day through time, nature, and human effects. Hence, some precautions are needed for protecting these historical structures from the corrosion and human effects. There are also two Ottoman Fortresses, called Seddülbahir and Kumkale on Dardanelles, Turkey in the same situation, however, the project team working with these monuments believes that the fortresses can be restored and protected only when it has been fully measured, documented and stored in proper historical information and management systems. [1] It is with this larger, long-term goal that the team of surveyors, architects, historians and archaeologists began in 1997 to working together on the Historical Documentation Project of Seddülbahir and Kumkale. The project undertaken at the Division of Geodesy, Istanbul Technical University (ITU) and the Department of History, Koc University; to explore a development of a multimedia supported four dimensional (3D + time) information system to aid geographically-oriented the documentation of the two Ottoman fortresses of Seddülbahir and Kumkale. [2] Project team decided first to develop pilot web-based GIS project for the cemetery where is close to Kumkale Fortress, called Kumkale Cemetery. After having geodetic measurement using GPS technique, produced all topographic maps using Autodesk productions, and historical information regarding the cemetery a base for GIS was began developing. GISs are tools for acquiring, managing, analyzing, and presenting spatially related information. The Internet enables a great number of users to access a common data stock. Internet GIS is a networkcentric GIS technology that uses the Internet and the World Wide Web as a primary means of providing access to the functionality (i.e., analysis tools, mapping capability) of GIS and to the spatial data and other data needed for various GIS applications. Rapid progress of Internet, application of data warehouse technology and the combination of GIS and Internet have paved the ways for the web distribution of GIS spatial data, it also makes the GIS space data management and application appear the characteristic of multi-user, distribution and web.

2 Internet has already been one of the important developing platforms of GIS, the function of GIS has been extended by Internet, and furthermore it becomes a kind of new GIS architecture. [3] Web-based GIS is becoming more and more prevalent as time passes. The World Wide Web (www) is a useful tool for the gathering and manipulation. Most information that is available in the world is now available over the Internet. Now much the same is true concerning GIS information. [4] Where formerly an individual would have to buy an expensive software package to use and manipulate the data needed for GIS, the same is not so today. With the advent of Java based programming, software applications for web-based GIS work are now available. Some of these programs require the user to buy some software, and others require plug-ins to be added to web browsers, but some require no special software additions at all. These use only the capabilities of your existing web browsers. [4] GeoHistoryQueryInterface application is an interactive tool designed to promote the usage consisting of a large geo-database with querying capabilities that includes the ability to output results in a map-based format using a GIS. This web-interface developed contains an application that enables query and extraction of the information belongs to cemetery and gravestones, and interactive mapping. The main function of the interface is to allow the user to easily obtain detailed information on graves for specific topics and locations including death dates, relationships, occupation, etc. This paper reports on the development and evaluation of GeoHistoryQueryInterface tool as a GIS viewer to allow a user to display and manipulate sets of geographical information. SYSTEM OVERVIEW Project Web Site Design Strategy Project web site that has been developing website for managing the multi-participant GIS project over the internet transforms a data source into communication hub and an analysis tool effectively with the following web pages: Project Information: Project scope, purpose, tasks, labor (human) resources, costs, publications, discussions, forums, virtual meetings, charts, reports, schedule, events, contact (address/phone) book, status, terminology, bills & invoices, etc. which are semi-secured public web pages. [Website Server: Microsoft IIS (CGI, ISAPI, PHP, JAVA, JS, HTML, FLASH)] Inhouse project (GIS) temporal database which is a secured private web page for project team members only to store the various different data sets. [Database Server: Oracle, MySQL] Project Location and Site Query/Analysis using a GIS viewer which is a free-access public web page for survey and feedback. [Internet Map Server (IMS): AutoDesk MapGuide, ArcIMS] Project website was developed with the purpose of that website is to allow project members and users share information about the project and discover the cemetery and historical background of it. Additionally database and IMS integration was provided to migrate a web-based GIS system. This all leads up to the interactive part of the site where the user can choose to view the data in three ways. Data can be viewed in a Flash Presentation of Kumkale Cemetery s with scenario animated. Data can be viewed in 3D in VRML and QuickTime environments.

3 The data can also be viewed in an interactive map. Users can also identify the gravestones and find out information about them. Major advantages of map server technology include: [5] GIS client software is not required, GIS software is installed only on the server. Therefore, GIS access is free of charge (unless a charge is imposed on the server connection). However, some map servers may require installation of a plug-in to run the software. The client interface is the web browser. All the user needs for access a web browser such as Netscape or Internet Explorer with a connection to the Internet. The end user does not need special GIS training or skills. The homepage of the project with the URL address which was developed using PHP, HTML, DHTML and JavaScript contains the link to the GeoHistoryQueryInterface. Data There are 276 gravestones in the cemetery of Kumkale. The data held for each gravestone is very comprehensive and includes personals, relationships, death dates, figure of gravestone, geodetic position. There are in fact 39 columns in the cemetery database. All geometric data is stored in AutoCAD-DWG file format containing layers within the map for topography, gravestones, contours, natural objects and boundary. System Architecture The system, web-based GIS, was implemented in Personal Home Page (PHP) using client-server architecture. Three tier client/server Web GIS architecture was used when developing GeoHistoryQueryInterface. Many clients (remote processors) request and receive service from a centralized server (host computer) in client/server architecture of a computer network. In this network architecture, each computer or process on the network is either a client or a server and each application is divided between a client and a server. Servers provide a given set of services, while clients demand these services. [6] [7] [8] Two-tier architecture refers to client/server architecture in which the user interface runs on the client and the database is stored on the server. The actual application logic can run on either the client or the server. A newer client/server architecture, called a three-tier architecture introduces a middle tier for the application logic. A three-tier architecture is a special type of client/server architecture of three well-defined and separate processes, each running on a different platform. [9] Figure 1 shows the overview of three-tier client-server architecture. 1. First Tier: The user interface which runs on the user s computer and web browser at the client side. 2. Second Tier: Related to the web processing which contains the web server, user interface and map server. The functional modules that actually process data. This middle tier runs on a server and is often called the application server.

4 3. Third Tier: A database management system (DBMS) that stores the data required by the middle tier. This tier runs on a second server called the database server. Data warehouse containing spatial and attributes data. [9] [10] The three-tier-architecture, is shifting the data load to the servers (thin clients, fat servers), the computing load, however, to the clients. [11] Figure 1: Overview of three-tier client-server architecture [10] In order to access to the GeoHistoryQueryInterface, users need a web browser like Internet Explore, Netscape Communicator or Opera and internet address of the project, Uniform Resource Locator (URL). URLs can be used to communicate between Hypertext Transfer Protocol (HTTP) servers (Web servers) and clients or send user s commands to the Web servers. Users can submit their requests by sending URL to HTTP server. The HTTP server will parse the URL strings and then launch the extension (Common Gateway Interface) to invoke the PHP program. Web Server communicates with Internet Map Server. Internet Map Server retrieves geographical information from Spatial Database and transform into appropriate format before sending the data to a Web Server. The CGI program on the server will create a new HTML with program execution and database query results, and post the new HTML file back to the client-side Web browser. Client Interface In this project first web based database query application was developed and then this developed application was integrated to GIS and obtained web-based GIS client interface, GeoHistoryQueryInterface, to allow a user to request services of the server and to display the results the server returns. These information management applications facilitate data queries and mapping with being ready access to multiple users, and requiring minimal system knowledge for effective use. The user interface brings user an interactive mapping environment to explore a geospatial data. User can make many maps after querying and print these maps and query result reports. GeoHistoryQueryInterface, developed using PHP, was designed as much as simple to create the desired queries for anyone who have never heard Structured Query Language (SQL) before. Once

5 the client interface is loaded the interface allows the user to obtain information about a single map layer by querying the data (attributes) associated with the map. The Query window consists of a Field drop list which will contain all of the fields of the attributes, an Operator drop list which contains the operators, the Value box in which the user can input the value or use the Get Samples button to obtain all the values from the field, an Add to Query String button which will add the query string to the query box and finally other query parameter buttons such as And, Or, Not and parentheses that can be used for complex queries. Finally the constructed query as SQL commands is executed. The complex interactive query textual results are obtained in the tabular form and reflect of it on the map by the way of changing map layer features color. Figure 2 and 3 show the user interface prototypes. The map-based output screen is produced using AutoDesk MapGuide which is a well known GIS application. The full functionality of AutoDesk MapGuide is available to the user including a zoom function allowing a closer inspection of a particular section of the map. The client s user interface is a customized AutoDesk MapGuide equipped with the Query Module which allows users to visually make complex queries. User queries are received through the MySQL database program, processed as a SQL query, and the results of the query are handed back to the client through the reverse path. MySQL was selected as a multithreaded database program on the server for handling queries to the cemetery database. This program runs on the database server and can be operated over the internet using phpmyadmin program. Figure2: A prototype of query interface

6 Figure 3: An example of database query application CONCLUSION Phase one of the project has now been completed. Further modifications and steps are currently under development to provide customized querying capabilities, analyzing techniques and faster communication link between the client and the server. Ease of use, user-friendliness, and reducing the volume of data transfer were the critical issues considered in the development. shows the user interface that has been coded using Hyper Text Markup Language (HTML), PHP and Java Script. The developers in the project are currently developing this type user interface in Java and HTML. Developed data query applications enables the freedom of multiple users in different locations to query site data 24-hours a day from a centralized, secured database to report ready graphs, charts, tables, and/or maps easily and quickly. Whilst the project has been successful in that it hides the size and complexity of the system behind an easy to use interface, the real success of GeoHistoryQueryInterface has been the development of a GIS optimized for use over the Internet that integrates various technologies in one model.

7 ACKNOWLEDGEMENT It is due to generosity of the Foundation Max van Berchem, the National Endowment of the Humanities, the American Research in Turkey, Leica Computer Systems and Technical Services and the Vehbi Koc Foundation that we were able to accomplish as much as we did over the past five years and all members of the Seddulbahir-Kumkale team give our sincere thanks to our sponsors. We would also like to thank the Turkish Ministry of Culture, the Director of Museums and Monuments and the Ministry of Defense for granting our team permission to research the sites Seddulbahir and Kumkale. REFERENCES [1] Guney, C., Ozsavasci, A., Ozoner, B., Thys-Senocak, L., Celik, R. N., (2002), Virtual 3D GIS Application at the Ottoman Fortresses on the Dardanelles, The International Conference On Heritage Management Mapping GIS and Multimedia, UNESCO World Heritage in the Digital Age, October 2002, Alexandria - Egypt [2] Guney, C., Celik, R. N., (2003) Multimedia Supported GIS Application For The Documentation Of Historical Structures, Survey Review, Vol. 37, No. 287, ISSN [3] The Study on Web GIS Architecture Based on JNLP, Li Luqun, Li Jian, Tian Yu [4] Why Use Web Based GIS [5] GIS on the Internet, Michael D. Broten, FAO Consultant GIS Specialist [6] Britanica Concise Article, Client/Server Architecture [7] Enterprise Storage Forum, Client/Server Architecture [8] Wi-FiPlanet, Client/Server Architecture [9] San Francisco State University, Information Technology Program Internet Architecture Course [10] Generating Online Map For Skudai Using the Minnesota Map Server, Malaysia GIS, Boonheng Beh, Alias Abdul Rahman [11] GIS on the Internet, Huan Ru, Thorsten Schulz [12] Implementing a Webbased GIS, C. J. Pilgrim, Dr. Y. K Leung, K. Mouzakis, S. Cameron, School of Information Technology, Swinburne University of Technology, Hawthorn, Victoria, Australia

8 Res. Assist. Caner GÜNEY Istanbul Technical University, Geodesy Division ITU Insaat Fakultesi, Jeodezi Anabilim Dali Maslak-Istanbul, Turkey tel: Assoc. Prof. Rahmi Nurhan ÇELİK Istanbul Technical University, Geodesy Division ITU Insaat Fakultesi, Jeodezi Anabilim Dali Maslak-Istanbul, Turkey tel: