Development Of A CAD System Concerning The Design Of Railway-Use Land & Subgrade Drainage

This thesis has accomplished the development of a CAD system concerning the design of railway-use land & subgrade drainage (YDPSCAD) , which is a fourth subsystem used in the design of railway-line following the plane-designed system, the vertical section-designed system and the transection-designed system in the integration of survey and design of the railway.This system is developed under the operation system named Windows NT 4.0. Its developing flat roof is Visual C++ 6.0, now one of the most perfect developing flat roofs based on Windows. Its gragh-supported environment is AutoCAD 2000, a CAD system composed of ploting and developing. The programming languge is ObjectARX 2000, the most powerful one used for secondary development in the development tools of AutoCAD 2000. This system can run under all Windows conditions.This thesis also expounds the key technics in the course of development work in detail, such as the technics of OOP, integration of gragh and digital and dynamic control about the mark, etc. There exists an excellent feature obviously in the system, namely, good computer-person interaction function and perfect system of automatic inspection. From the preparation of the data to the input of the data of the dialog box, command conducting, eventually results' output, there are corresponding prompt informations.At the end of the thesis, there is a vivid example provided. The No.l Survey and Design Academy of the Railway Department has successfully carried out about hundreds of tasks of the design of railway-use land & subgrade drainage with the help of the system, which is proved valid in theory, stable in operation and easy in conduction.