Development And Research Of An Examination Question Bank Management System Based On Integeral Coded Genetic Algorithm

Facing a greatly good situation of fast developing of current education business,a high request for standardization of the examination in each college is put forward.It is that under the same examing content and request we should compose a lot of test papers with greatly different but having equal effect from each other.The key is design of the examination question bank management system,which can produce high quality test papers and they are fitted for each course outline,and these test papers are composed of automatically by a computer.Because the examination question bank management system has a very important theoretical significance and using value,at present,in educational test management department the developed and researched work on the examination question bank management system has been a hot issue.This thesis fixs attention on development and research of the examination question bank management system in the C/S construction.I select current popular Delphi language as developing tool and SQL Server 2000 as database management system(DBMS),and I adopt a design method of structured programming,namely from top to bottom for sub-function gradually,and I use data flow diagram and programming flowchart to descript the system design and realization.The core function of the examination question bank management system is automatically composing test paper. It is designed to fit for request of user,and has been a certain constrain condition and is ownned a high quality of test model to adopt corresponding composing test paper strategy.Then it selects corresponding test questions to compose test paper according to the model of test paper.The process of composing test paper,which is fitted for examination parameters,such as types of test questions,amount of test questions,difficult coefficient,the knowledge points distribution, the score of test and the time of test,finally the test paper being composed of these attributes of various concrete parameters according to experience and examination purpose,is based on expert knowledge of decision process.This thesis is targeted on genetic algorithm ,which is used in automatically composing test paper,carrying on illustration in detail. I carry on detailed of the analysis and research on the cause of same code problem in opration of genetic crossover in realizing process,and put forward a kind of better resolving method.This is an importance and difficulty of the thesis,and also a brilliance to be worth discussing and researching.The whole examination question bank management system is designed and developed mainly for teaching and examinating management sections of each college in Normal University in Guangxi. It is that I develop the software to help teacher easily composing a high quality test paper. This thesis mainly includes five parts in basic structure and content essay,main function of examination question bank management system and its sub-system,key technique of the examination question bank management system,optimization of algorithm and software test,and so on.One,Basic structure and content of the essay: At first,incoducing background selected topic for study,current situation,significance and task of done.Then carry on request analyse,feasibility analyse and overall design in examination question bank management system.Next do more work in sub-function detail design,database design,concrete system realized design,in the meantime carry on software test for correctness of the system function.Finally in two ways of theory and apply carry on a discuss in detail for genetic algorithm of the key technique of the examination question bank management system.Two,The main functions of the system and its sub-system examination question bank are these: 1,The user management--the assignment of different legal power to different user. 2,The maintenance of the examination question bank--it can input,updata and delete examination questions. 3,Composing test paper--it can compose test paper by hand or by computer automatically. 4,The manegement of test paper--it can output composed examination questions in the form of test paper. For easily to use examination question bank management system,I chose the Microsoft Word 2003 as the terminal output form of the software,so can edit the test paper easily. 5,Data protection--the administrator can do the job of backup data and restore data. 6,Help--explaination how can use the examination question bank management system and take notice of points for attention.Three,Key technique of the examination question bank management system: The basic theory of automatically composing text paper is genetic algorithm,and it is the heredity and the evolution process that imitates living creature in the nature. It is an algorithm adapted globle optimization of searching.The key technique of the system is a basic itegeral coded genetic algorithm.The origin of the evolution is start with a group having a certain number of individual,then caculates each chromosme of relative error (regard as fitness by taking reciprocal of the error) of the original group and all offspring after evolution,genetic crossover changes genetic constitute of the chromosome,genetic mutation produces new individual and chromosome selection choses the best individual in all groups,namely the best one is survival and the worse one is eliminated,such as the same basic operation.After passing down a certain descendants,selects the best one chromosome which the relative error is min(the max value of its fitness) in all descendants.Decoding the best chromosome,can obtain a group high quality test questions, which they are fitted for requestment of the user,then test paper are composed of them.By carefully researching the same code problem which is appeared after genetic crossover,I adopt to shift crossover point to left side,in this way the success rate of genetic crossover is increased in 8 times in these testing conditions than before.Crossover size of requestment can be ensured in sufficiently.Moreover the running time is decreased in 8 times from whole scale.Four,Algorithm optimization: I analyze and research the same one problem from different point of view and thinking pattern,then I want to find the better or best algorithm and programming skill above promising in right way and right result,and the running speed of the program can be raised greatly .In the process of software programming I adopt some optimized measures.The purpose is to reduce the running time.Five,Software test: For promising the correctness of result and the accuracy of each model in programming,I have tested the whole system and its every sub-system functions.After promising the correctness of each model and its sub-model functions,transplant them to the system of examination question bank management system.Design every program as common function according to these models for calling them when needed.At the end made a overall summary to the characteristics of the system,and put forward some problems left,then point out researching direction in the future.