The Development Of Decision Support System For Tobacco Diseases And Insect Pests Management

Tobacco diseases and insect pests threaten tobacco production and human's health badly, not only a deadly factor limited field and economic value of tobacco and cigarette, but also caused a great damage to agricultural production in China. As an important branch of agricultural diseases and pests management, more and more advanced technique were applied on the control strategies against tobacco pest.Combined decision support system (DSS), the last word in information technology, with flourishing computer database technology, the dissertation studied on the critical techniques in construction of decision support system aimed at tobacco diseases and insect pests management, included: application model design; function module design; database construction of SQL Server 2000; application programming of Visual Basic 6.0 and its optimization and publication. Through this project, technology and its realization of DSS based on advanced program developing language Visual Basic 6.0; database management system SQL Server 2000 have been clarified. Furthermore, the architecture of application model construction and function module design in "DSS for Tobacco diseases and insect pests Management" could provide necessary scientific theoretic basis for integrated management against tobacco diseases and insect pests and its DSS application. Meanwhile, database constructed in system as the most abundant database of tobacco pest current in China, would extent field and enrich the whole study system for tobacco plant protectors.The project is supported by the Science and Technology Project of Chongqing Tobacco Co.. From the above research we made the conclusions given below.1. Application model designThe system applied SQL Server 2000 on construction of tobacco diseases and insect pests database; Visual Basic 6.0 on development of application programs; and database access with ActiveX Database Object (ADO) through the interface of the OLEDB data source. The results showed that, based on visual interface; object-oriented and event-driven structured programming properties, Visual Basic is available to develop application in Windows operate system, and the function is powerful. By using Open Database Connectivity (ODBC), Visual Basic can directly access or in pattern of establish connection to process and manipulate background SQL Server database.As an open API calls, ADO made up the nonsupport of memory accessing, which caused Visual Basic enable to use OLE DB provider directly. ADO supplies executive operation including connect data source; compile access command; executive instruction, i.e. SELECT script; routine errors analysis, etc.2. Database engineering designSQL Server 2000 database system were adopted to management data of tobacco diseases and insect pests. The results showed, the core of system architecture was database engine, each of which contained several database, and each database composed plenty of database objects, i. e. table; view; constraint, etc. Meanwhile, the system supports various data types and holds an excellent mechanism for log management.As a relational database, SQL Server 2000 database establishment via wizard tools made the method simply and consecution clearly. Furthermore, Transact-SQL language SQL Server used were compatible with most of ANSI SQL standard and provided several extended and enhancing functions, so as to joined application programs rather and easy to transplant.Systematic database Tabacco_dss stored data including the occurrence; damage; prevalence; forecast and integrated management strategies against tobacco diseases and insect pests. The six user-defined Table: Diease; DisTypes; Pests; PstPart; Spc_Picture and Tobacco_Dig memorized records of tobacco diseases; type of diseases; insect pests; type of pests; pictures of special topic (Pests and Digital tobacco) respectively. Records and fields of user-defined Table elements reached 137 and 39 each, character data to 65535, (Chinese characters 61737 non-Chinese words 3598 there into), and binary image data to 388.General procedures for database engineering design were clarified: requirement analysis, conception framework design, logic framework design, physical framework design, database implementation, and operation and maintenance of database.3. Engineering Framework designThe dissertation studied on project establish, addition of standard module and class module and their management of constant; variable and user-defined function, and configuration of ODBC data source in engineering framework design process. The Form addition; Command design and code programming, etc. were all carried out after the establishment of project file (.vbp), which is the main documents in Visual Basic application programs.In the system, standard module were applied to manage constant; variable and user-defined function. Database operations corresponding table element were encapsulated in the class module. Combined global variable; module-level statement; and universal process, standard module were independent of the project unit and set up the communications from Form to Form, Form to project. Class module calls were as well as execution of database operation. The utilization of standard module and class module are indispensable while database application programming.ODBC API were isolation from database system and constructed on call-level interface basis. In the process of ODBC data source configuration, driver manager supplied a certain diver program according to database information provided by data source. ODBC administrator integrated the resources above to build the connection between ODBC and database and application programs then.4. Interface design of application programThe objects of Visual Basic were abstracted to Form and Command. While developing application programs, foundation of visual user-interface and its property setting-up accomplished via specifying the attribution of Form and Command. In the process of "DSS for Tobacco diseases and insect pests Management" interface designing, the frame of Form were divided by function module, each of which took the same style.There were altogether 24 Form added, 13 standard Command (i.e. Textbox; Image) cited, ActiveX Command included Microsoft Common Controls 6.0; Microsoft ADO Data Control 6.0 (OLEDB); Microsoft DataList Control 6.0 (OLEDB); Microsoft Common Dialog Control 6.0, and 1 insert-abled object Microsoft Word Document in the system.The concept of "prettify command" were put forward firstly in interface designing. Through specifying certain attributions specifying of a command, the prettification of running interface were realized. When running the Form, it had non-response to user action (Attribution of Enable is True). Application of "prettify command" signified much to the friendly interface.5. Function module design and code compilingThere were four modules: tobacco disease diagnosis system; tobacco pest diagnosis system; forecast system and systematic manipulation, designed in system. Each of modules corresponded to certain systematic function and accomplished independent database operations against objects (i.e. Table). The implementation of module function was finished by Form design and code compiling.Availed of event-driven programming mechanism, Visual Basic engineering realized its systematic function via methods or events code programming, which were supported by Command in Form.Systematic function of "DSS for Tobacco diseases and insect pests Management" is powerful. With function module design, system possessed the capabilities: image data recognition; character data retrieval; real-time data derivation; information data browse; text data editing and hypertext data link.In database programming, "buffering Command" was taken to switch data source. Through reading certain Field in first data source, then specified new linking parameters of another data source in SQL language. In this way, the instruction of database operation was consecution clearly, and still easier to SQL code programming and errors analysis. Meanwhile, it avoided the problem of SQL sentence complexity, unnecessary and over elaborate formalities, database access conflict, etc, brought by database manipulate language when just one Adodc Command action on the same Form.As a key technology in the study, application of "buffering Command" might provide an important reference for development of database application programs.6. Optimization and publication of application programImage editing software Adobe^? Photoshop CS and Microsoft^? Paint were applied to prettify the picture showed in application program interface. Systematic help file myhelp.chm was compiled with tool Html Help Workshop. The HTML files used in myhelp.chm were established via software Microsoft^? Office FrontPage 2003.Finally, after the development of application program, Visual Basic 6.0 tool "Package & Deployment Wizard" was utilized to finish the system installation program making.7. SummaryTo sum up, integrated module design and decision support methodology, the study developed expert system for tobacco diseases and insect pests management. Tobacco pest database was constructed based on "Integrated Pest Management" (IPM) theoretical basis. Through system analysis and function design, the system built on SQL Server 2000 as database management system and Visual Basic 6.0 as application developing platform. The function implemented included data management, data retrieval, prediction and evaluation, chart orientating and text editing, etc.Tested and applied results showed, "DSS for Tobacco diseases and insect pests Management" can be professional software in the field of plant-protection science, to provide support to the tobacco diseases and insect pests study and IPM decision making, with friendly interface; high reliability and convenient access.