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Development and Application of Knowledge Management (KM) System Information Platform of GEF Haihe River Project ZHANG Junxia1 SHI Zongfeng2 FU Xiaoliang1 1. Haihe River Basin Commission MWR Tianjin, P.R.China, 300170; 2. Tianjin Lonwin Network Science & Technology Development Limited Corporation, Tianjin, P.R.China, 300181 [email protected] , , Abstract Firstly, The paper introduces the basic situation of the GEF Haihe River Project, then is the KM system overall structure description, which provides the key technique of information exchange and application control platform. At the same time, according to the relation of the platform, the database and application, the platform’s soft system structure, the platform’s preserved interfaces for each projects as well as the platform environment design, each business application system can be realized perfectly with the help of the KM platform and can get all the monitoring and measuring information and history materials from the database, then a kind of actual mechanism will be built accordingly at the basis of information share, exchange and co-operation. Furthermore, the platform can bring distinct social economic profit with good application effect and should have broad extending future among the fields such as water resources and environment protection, etc. Key words object relational mapping, inversion of control, lightweight container, IoC, AOP 1 Project Introduction Haihe River Basin is one of the most important basins flowing into Bohai Sea. Function of the Bohai Sea’s ecological system has been reduced by the serious land pollution sources of cities, industries, agricultures and stockbreeding in the basin. Through the efforts of related departments of the Chinese Government and support of the World Bank, we have got Global Environment Facility (abbreviated as GEF) grant Haihe River Basin Integrated Water and Environment Management Project, the overall objective of which is to promote integrated management of water and environment in Haihe River Basin, realize reasonable allocation of water resources, and improve utility efficiency and economic benefits of water resources in Haihe River Basin, to restore ecosystem and alleviate water shortage, reduce land-based pollution in Haihe River Basin to Bohai Sea, and improve in the true sense quality of water environment in Haihe River Basin and Bohai Sea. The total cost of the proposed project is US $33.32 million, which includes US $17million of GEF funding and US $16.32 million co-funding of domestic organizations in China. Implementation period is from 2004 to 2010. The focal point of the project is Ministry of Finance, the organizers are Ministry of Water Resources (abbreviated as MWR) and Ministry of Environmental Protection, and it is implemented jointly by Haihe River Basin Commission (under the MWR), Zhangweinan Canal sub-basin, Tianjin Municipality, Beijing Municipality, Hebei province and the water resources departments and environment protection departments of the related cities and counties. The project is consisted of four components, Integrated Water and Environment Management (abbreviated as IWEM), Development of the knowledge management (abbreviated as KM), Tianjin coastal wastewater treatment, and Project management and training. KM system serves as one of the cores of GEF Haihe River project, also the center of storage, management and share exchange of IWEM information in Haihe River Basin. To build a foundation platform for KM on water resources and environment of the Haihe River Basin, establish a mechanism sharing and coordinating data under joint KM-ET management, establish application system of water resources and environment in the Basin and integrated application system of water resources and environment, conduct scientific evaluation, analysis and forecast on water resources and environment, and provide timely and effective scientific bases for integrated management of water resources and environment in the Basin on the basis of exchange, share, integration and exploration of existing information resources and by making sufficient use of 3S (GIS/GPS/RS) technology. 155 2 Construction Schema of KM Platform 2.1 Overall structure of KM system Owing to its dispersed customers, large number of client points and low request for real time, layered Browser/Server structure and J2EE pattern benchmark are adopted to KM system. Databases layers and operation logic layers are both equipped on the server, and client works with explorer. See Fig. 1for the framework of KM system. Fig. 1 Overall structure of KM system 2.2 Platform design of KM system KM platform includes two functions: information exchange and application control. Based on characteristics of the KM platform, data and operation interfaces shall be provided to reduce dependency of the application system on the database as much as possible. Some general-purpose groupware, controls and permission certification models shall be provided, too. The architecture of the KM platform is shown in Fig.1, where the OR-Mapping in the information platform shall provide general database access control and communication interfaces; the IoC container shall provide management on Bean and other resources; the AOP interception shall provide intercepting controls and management for aspects. Permission certification and journal log and other general-purpose function modules shall be provided, too. The upper layer on the platform shall provide part of reusable functionary groupware and part of general-purpose displayable controls. 2.2.1 Data exchange Main tasks of the data exchange shall be establishment of information sharing and exchanging mechanism, standards and interfaces of access and calling. The principles of unified operation maintenance and separate usage of data shall be always implemented. The targets are to solve impedance-mismatching problems between the upper level and the database, dependency between partial decoupling business logic models and database, and to provide management on database connections. The data exchange service shall adopt the OR-Mapping format in the current 156 J2EE solutions, which is more practical. Object Relational Mapping (abbreviated as OR-Mapping) is a technology used to solve mismatching between the object orientation and the relation database. In short, OR-Mapping uses meta-data of mapping between objects and database to retain the objects in java programs into the relational database automatically. In essence, it is to convert the data from one format into another. OR-Mapping can control objects and mapping of the database records, while the costs for business logic are much lower than that for handwriting maintenance. Functions provided by OR-Mapping in the platform are as the following ones: Interlink with factories. Manage creation, destruction and acquisition of database connection. Mapping management. Provide object relational mapping on database tables by way of declaration, use java statements and meta-data attributes, and provide simple query interfaces such as major keys, etc. Semanteme combination query. Some queries must be in the form of special semanteme combination, and the corresponding semanteme combination interfaces can be provided here. Native SQL query. For the more complex operations in SQL, interfaces for direct executing SQL statements or (storage) processes can be provided. Persistence function .Revisions to the domain models can be updated to the explicit interface of the database (non-transparent persistence). Business functions. Business supporting interfaces shall be provided. 2.2.2 Application control The application control shall provide a stage for the KM application system and application tools, and shall realize unified, safe and smooth cutover, build a bridge between the application system and the database level in the capacity of program aggregate. Unified interface design, program process management, user interface management, I/O management and logging management shall be realized. Besides, more conveniences shall be ensured for systematic expansion and new function addition in the future. While a unified controllable platform is provided, coupling between the upper level business application system and the lower level database shall be reduced to the maximum through the KM application control service. The application platform shall be divided, in turn, into the following parts: a light-weight container, AOP interception, general-purpose module space, permission certification and application controls, which are described in the following paragraphs. (1)Light-weight container The container in the application control service is of a light-weighted type, which is based on inversion of control (i.e. management on groupware and bean shall be controlled by the container, instead of program control). The Light-weight container in the platform can provide the following functions: Life cycle management. Manage creation and destruction of the running groupware (Bean or other resources). Query positioning (manager).Define the groupware (or resources) to be called by way of a certain policy (usually by file name). Configure its interface. To provide configuration policies. The upper application programs can control attributes of Bean or other resources. Dependency analysis. To manage dependency relations among groupware or resources and conduct dynamic management according to relations. Coordinate communications. To coordinate the lower level OR-Mapping and etc. and upper level business calls. Expansion supports. Expansion is available for the corresponding interfaces if there is a need (e.g. Web Service and etc. can be inserted into the platform). (2)AOP Permission, log and business processing etc. in the application platform shall adopt the interception-based aspect oriented programming (i.e. business logic codes are not used in controlling all these, while unified interception shall be used, instead). AOP is the abbreviation of Aspect Oriented Programming, which is a programming method that becomes fashionable in the recent years. AOP is a supplement to OOP and a longitudinal cut of the OOP system, realizing system decoupling from another aspect. AOP provides OOP with another reuse possibility. Functions of AOP provided by the platform are as the follows: Provide an interception interface; Provide an interception processing interface; Aspect processing interface; Processor registration interface; Aspect ② ③ ④ ① ⑤ ⑥ ① ② ③ ⑤ ④ ⑥ 157 registration interface. (3)Common component & control Common component is an assembly of some reusable and functional components, while common control is an assembly of are some reusable and interfacial components. It can protect the consistency and maintainability of multi-business management system in KM system better to use the common component and control, while reduce development time and the possibility of error. (4)Permission and application control Permission control adopts role base permission control and permission mode with AOP interceptor combined and is capable of configuration, fine permission control modes. 2.3 Relations among KM platform, database and applications The KM foundation platform is a protective shell for the database, and also a window to provide data, which provides interfaces for the users in exchanges of data. All the applications (including application systems, data providers and claimers) shall be one of the database users only and the platform shall provide it with dataset through the corresponding permission configuration files, i.e., each application shall be able to see one dataset permitted to it, instead of the whole database. The database under protection of the platform shall have only an obligation to provide data, instead of providing business logic, thus avoiding continuous expansion of the database owing to increased business amount, which may become even to an extent of uncontrollability. At the same time, owing to the fact that business logic is distributed to application programs, points with high pressure are dissipated, resulting in great alleviation of operational pressure on the database. Fig.2 is a sketch that shows relations among the KM system platform, database and applications. Fig. 2 Sketch to show relations among the KM platform, database and applications 2.4Architecture of soft system based on the KM platform The system architecture based on the KM platform shall comprise four hierarchies, being the user interaction, application program, platform and database from the top downward, as shown in Fig.3. (1) The user interaction level shall face to users directly, provided users with interface of selection & alternation and output & feedback. (2) The application program level shall realize business logic processing flows, conduct controls over inputs and outputs, ask for different business data by unified interface provided by information exchange and application control platform. (3) Information exchange and application control platform level shall mainly be responsible for permission control and data exchange services. It shall control the users over their usages of data and operational function trees, and make log records according to requirements of the system and application. It shall provide a unified data exchange interface and data users of the KM system shall be able to access data through this interface, while the platform allows for special processing requirements within controls by the platform. (4) The database level shall be a pure data provider and the meta-database shall make records about 158 identifications, alias of database, user permission in the database, descriptive information on the database in the database management system and provide information support for data services. The application database (underlying database) shall be an agglomeration of data in the KM application systems. Fig. 3 Architecture of soft system based on the KM platform 2.5Transactions supplied by KM for all items KM platform is the bridge to visit the central database for various application systems, which provides information exchange transaction for application systems. Models and ET project with remote sensing also use the information exchange transaction of the platform to exchange data with KM database. KM platform provides application control transaction for application system to control all application systems’ rights, log and malfunction treatment etc. Because spatial database is visited by GIS system and uses special data structure of GIS system. GIS software limits the visit function of database and spatial database does not visit through KM platform but the application control section of platform controls the visit right of spatial database. KM platform provides data visit transaction for the other sub-items of GEF Haihe river project, such as strategy study and IWEMP, and provides basic data and tools for input and output of results combined with application system KM platform provides data import and export transactions for county-level KM system and supports data exchange between basin level and county level. KM platform provides data exchange transactions of basic data for model systems such as DWEMM and SWAT so as to exchange data with KM system database clearly and provides transactions for storing model result into KM system database so that the result may be used by KM system. KM platform provides transactions for all models to exchange data directly and increase efficiency of database visit for models. KM platform provides data, model result and tools or application modules which exchange with KM platform, central database and application system. Fig.4 shows the organization of transactions supplied by KM platform for all items. 2.6 Environment Design of KM Platform (1)JDK environment: jdk1.4x above (2)Web server environment: Tomcat4.x,Tomcat5 & WebLogic8.x (3)Database: Oracle9i, SqlServer2000 159 Fig. 4 Transactions Provided by KM Platform for All Items 3 Conclusion and Suggestions KM platform, among the total KM system in basin level, is the information bridge which is connected each business management system. With the help of the KM platform each business application system, it can be realized integrated perfectly and can get all the monitoring and measuring information and history materials from the database, then to found an real mechanism which will be built at the basis of information share, exchange and co-operation accordingly. The KM platform core groupware- Data access and lightweight container groupware is already estimated as one of world class level products at the Scientific Product Identify Meeting which is arranged by Tianjin Scientific and Technique Committee. Using this technique the developing efficiency, at the same time the developing and maintaining capital can be saved, the developing process can be more canonical and accord with national and field standard. Furthermore, the social economic profit can be more distinct with good application effect, it will have prosperous extending future in the water resources field and environment protection field, etc. References [1]Kuang Lei, Yang Lu ming. Research on Object Relationship Mapping[J].Computer and Information Technology, 2007, 4:33-36. [2]Wang Chun zhi, Tang Jun wu. On IoC Pattern and Lightweight Container[J]. Journal of Hubei University of Technology,2006,8:52-54. [3]Lou Feng, Sun Yong. Design and Implementation of Lightweight IoC Container[J]. Computer Technology and Development,2007,1:91-97. 160