|
Design and implementation of a web-based GIS for the Iranian Roads Information  Saeid Mohsen Kalantari Soltanieh M.Sc. Student, Dept. of Geodesy and Geomatics Eng. K.N. Toosi University of Technology Vali_asr St, Tehran, Iran, P.C. 19697 Tel: +98 21 8789357, Fax: +98 21 877 9476 Email: sm_kalantary@yahoo.com  Ali A. Alesheikh Assistant Professor, Dept. of Geodesy and Geomatics Eng. K.N. Toosi University of Technology Vali_asr St, Tehran, Iran, P.C. 19697 Tel: +98 21 877 0006, Fax: +98 21 877 9476 Email: ali_alesheikh@hotmail.com  Hossein Mohammadi M.Sc. Student, Dept. of Geodesy and Geomatics Eng. K.N. Toosi University of Technology Vali_asr St, Tehran, Iran, P.C. 19697 Tel: +98 21 8786218, Fax: +98 21 877 9476 Email: hoseinmohamady@yahoo.com
Introduction The Internet is a global, public collection of individual networks run jointly by private organizations, universities, and government agencies. (Intranets are private networks that use Internet technology.) The Internet can be viewed as a physical network, which interacts with computers, software, and data on different levels, or tiers. For the purpose of this project tree tiers of Internet interaction are defined as client, middleware, and server. It’ll be discussed where IMS components fit within this framework. Dynamic link libraries Libraries store commonly used procedures. As project executes, it can call procedures from libraries. This technique is especially useful for procedures used by multiple projects; only one copy of the libraries is kept in memory and its procedure can be called by more than one project. Widows use dynamic link library (DLL) to store collection of procedures. The DLL file is the linked to your project when it runs. DLL files have extension of DLL. Windows application routinely uses DLLs. A project can call a function from the libraries and pass arguments if needed. The function is maintained separately from the programs that call it. Therefore changes are made to the internal workings of a function in a dynamic link libraries without having to recode the entire project. Most of the windows DLLs code in the C language and require some use of C syntax. Don't worry if you don't Know C. You only have to pass arguments to the library procedures. Kntudll is the in-process, dynamic link library (. DLL) component that extends your Web server software so that it can manage requests and responses from the map server and administer map services. It manages connections with map services running on one or more map servers. GIS in the web Maybe you have seen numerous web-based mapping, in addition to the map display it is needed to support zoom, pan, identify and measuring as basic function of GIS. For application development it’s needed to use additional and maybe complex functions. Many web sites support various GIS functions and each of them probably has different design strategy. Web GIS application involve a user, client, who contacts a server for some information. Commonly two strategies have been used for web GIS applications. The first extreme is for the server to pass data and mapping application to the client. That is the server supplies the data and the programs, but all GIS functions are carried out on the client side (client side strategy). The second strategy is to have the client indicate the type of map of functions that wishes to run and for the server to pass back the map the client request. Several factors influence the strategy of web GIS. Ease of the use, amount of data, function, attributes, disk space, RAM, site receiving traffic are factors that web GIS strategy is relevant to them. Next section debate about needs of TTO Web GIS for offering a suitable strategy.
Page 1 of 4
| Next | |