Research And Implementation For Clinic Count And Charge System Based On Three Layer Structure

The information of the hospital is an important part of the current traditional profession information. Weather is the challenge of the hospital management and the business process that SARS (Sever Actue Respiratory Syndrome) in the year of 2003 bring, or the demand of the treatment service that people making, all require hospital to improve the service quality through changing the traditional management and the operation mode by the information of the hospital.Hospital Information System belongs to one of the most complex enterprise information systems hitherto. Construction cycle of traditional HIS based on client/server is long and function is not perfect enough, They have generally the phenomenon and questions that system responds slowly, centralized control is difficult and dependability is poor. So it needs one kind of scientific method to analyze and design Hospital Information System. Hospital Clinic Count and Charge System that this paper will talk about is a subsystem of Shen-zhen 999 hospital information system(999HIS). This system adopts object-oriented modeling technology and method which can more deeply catch the requirement of users and setup good base for successful development of this system and software maintenance during later stage. It is Windows DNA system structure based on three layer structure and COM+ technique criterion adopted in development process that make the development cycle abbreviate and the system performance, scalability and security improve greatly.After studying and probing into current development situation of hospital information system and development of software engineering at present, the paper indicates that to use Windows DNA system structure based on three layer structure, and adopt program design theory based on COM to guide system development can set up application system having high scalability and good performance, thus solve all sorts of technologic difficulties that existing HIS system faced with.After studying the systematic structure developmental course ,Firstly, The paper introduce client/Server structure and it's shortcoming. Client/Server lay user interface and business logic in the client. Though the structure is simple, it bring the intrinsical questions that system responds slowly, centralized control is difficult and dependability is poor. Secondly, The paper introduce three layer structure and it's excellence. Windows DNA is entirely based on three layers service model. It divides application system into three layers: users interface layer, business service layer, data service layer. User interface layer offers user interface, mainly gathers data submitted by user, checks data form, uses operation provided by component in the business service layer; disposes data returned by component, displays data in the user interface. This layer is developed by Visual Basic. Business service layer takes charge of dealing with application request of user interface layer and accomplishes business affairs logic calculation task, then returns the result to users. Business service layer is separated from the business logic of client. It concentrates on server parts and shares for all users. The independence of business logic and three features of the COM component: language independence, process transparence, reusability solve the intrinsical problem of Client/Server Structure. Business service layer is a kernel part of the whole application. And COM+ is the heart of the whole application. This layer is developed by ATL (Active Template Library). Data service layer offers data source for application. This layer uses MS SQL Sever 2000 to store data. After mastering Windows DNA system structure based on COM+ technology, we can use it to design HIS system. After analyzing main business logic and workflow of hospital drugstore, Rational Rose 2002 is used to set up system modeling and draw the blueprint of whole system for guiding system development. When designing, we pay attention to design of the interface of middle business component, because business ser...