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At present, the Changzhou campus of Hohai University has applied a relatively mature and professional application management system, such as library management system, educational management system, financial management system, computer room management system, electronic control management, and some professional manufacturers. In some aspects, more mature application systems have been developed. In order to protect the pre-investment of schools and the smooth upgrade of the system, inter-system interconnection, data sharing, and elimination of information islands must be implemented with the "campus card" system. Docking extensions.
First, based on the "campus card" system scalability
Extensibility design is one of the principles of the "campus card" system design. The scalability of the "campus card" system's internal system includes the following aspects:
(1) Extensible design of card applications. The "campus card" system uses the card directory manager to uniformly plan the user unit card structure. In addition to cardholder's unified identity authentication information, personal basic information, and wallet information, the rest of the card can be defined in the "Campus Card" system card directory manager, unified management, and achieve the custom requirements of spare sectors. For example, in the campus card, you can define a shower wallet, a control wallet, and a library card information through the card directory manager to meet the different requirements of different application subsystems.
(b) The extensibility design of the terminal product. All terminal products of the campus card system adopt the modular design concept of 1+X. It adopts the principle of embedded design and adopts a unified hardware and software platform. It provides different functions and business modules for different environments and business requirements. Terminal equipment of different nature of business. Online downloading to the corresponding terminal product update application via the network does not require opening the lid to replace the application chip.
(c) Extensibility design of network products. All network products use international standardized products to ensure common use and expansion. The backbone network uses the campus network, and campus outlets can be used directly to facilitate access and expansion. Subnet lines are designed in accordance with the standard local area network star structure. The terminal products are isolated from each other on one bus. Increasing or decreasing the number of terminal products will not affect the terminal products that are already in use and ensure scalability.
(d) Extensibility design of software products. Application software products adopt three-layer structure design and development, standard modular structure design, integration, split, and maintenance are very convenient. Users can define and organize these standard modules by themselves and use the “software interface generator†equipped with them to quickly form New application management system. The software system adopts the "1+X" application mode, which provides a simple, fast, and convenient condition for the development of a new extended application system (X) on the basis of a common module platform. From the software upgrade aspect, because the software is centrally installed in the application server, the local upgrade implements the "hot-plugging" technology of the functional modules. The upgrade does not affect the normal operation of the system and brings great convenience to the software upgrade [2].
Second, based on the third-party application system docking extension (a) extended docking logic diagram
The "campus card" system provides third-party docking methods based on the principle of open standards: data level, functional level, and business level. Business data is the core of the campus card system. The campus card data is divided into three types: public data, private data, and sensitive data. According to three different data types, the campus card system data exchange platform uses XML standard protocols to provide various business data for third parties based on different security levels.
The unified presentation layer (V), business logic layer (A), data control layer (C), and data access layer (M) in the "campus card" system architecture all provide WebService interfaces based on the XML standard protocol, which can be third-party services. Layers to achieve docking [3]. The "campus card" hardware platform provides a set of docking API functions to meet the related aspects of the third-party system's hardware operation functions, as shown in Figure 1.
(II) Data level interconnection
The campus card data is classified into three categories: public data, private data, and sensitive data. The main business data of the campus card includes the original transaction certificate data, original attendance data, and transfer certificate data. Business data, business result data, and basic data of the business platform. According to different types of business data, different levels of security are used to connect data layers [4].
There are mainly three types of docking methods: metadata level, data exchange technology using open XML protocol, advanced technology, strong data interaction, high security, and high real-time performance; at the file level, the two sides define a file format for exchanging data. , Data format, mutual document import and export functions, poor real-time, file format is not easy to unify; database table level, docking is simple, data interaction, real-time, high, the database without any security protection, system dependencies.
Third, Docking Extension Based on Private Charging Machine (1) Docking Network Structure
The dedicated billing machine has two communication ports, one of which (RS485 or TCP/IP) is connected to the "campus card" information management system to achieve functions such as clock synchronization, blacklist synchronization and transaction uploading, and the other (RS232 or TCP) /IP) Connect to a third-party software system to enable reading and writing of the IC card.
(B) specific functions and implementation process
The docking system call interface function completes the cardholder identification and deduction process as follows: the dedicated charging machine is correctly connected to the computer serial port (RS232) or network information port (TCP/IP); the dedicated charging machine power is turned on; the call is provided Dynamic library or use the method provided by ActiveX control; call to open the serial port function to open the serial port connected to a dedicated billing machine or establish a socket connection with a dedicated billing machine; the library management system issues a card reading command; if it is a valid card (special terminal automatic judgment ), library management system will be the user card card number and other basic personal information (ie student number, library card number), library management system according to the card number for other processes (such as borrowing, returning books, deductions and other business processes); If it is an invalid card (special terminal automatic judgment), the library management system will obtain the information that the user card is illegal or blacklisted, and the library management system may stop the other business processes of the card; if the library management system needs to deduct Fees, calling the deduction card amount function, incoming receivables amount, dedicated POS machine to automatically deduct the deduction; dedicated P The OS machine displays the transaction result information in the display window according to the normal consumption flow, such as the transaction result transaction amount, the balance before and after the transaction, and returns the transaction result information to the library management system; calls to close the serial port function to shut down the serial port or disconnect the Socket connection; terminal POS The machine uploads the transaction flow to the campus card system through the RS485 network and completes the merchant settlement process.
IV. Conclusion
The above types of docking methods are flexible and versatile. In addition, each terminal device also provides a docking interface and docking method. The third-party product provider or customer can use the application program interface API provided by the “One Card†construction unit to carry out the transformation of the original system, or The original system's source code or data structure is transformed to achieve data center data, cardholder card data (such as personal information and wallet balances), terminal product data is completely shared, and takes effect in a timely manner. There is no link trace. Since the access to the database is based on the middle layer isolation technology and the hardware encryption verification mechanism, all types of linking methods are safe and reliable, and the "one card" information of the Hohai University Changzhou Campus is implemented in the school with the shortest time and fastest speed. , Widely shared and applied.
Gift rulers are used for advertising and promotion. They are divided into Steel tape (steel tape) and leather tape (PVC plastic fiber tape). They are usually cute and compact. Tape measures are also called measuring tools. Eighty-five percent of the world's tape measures are exported from China.
2, the characteristics of the tape measure
(1) The tape measure is too deformed and will not fail
Why didn't it fail? The spring in the tape measure is very long, and its range from completely relaxed to fully tightened is very large. The entire stroke of the tape measure includes it, and there is a margin at both ends, so the tape measure will not fail.
(2) Pull one meter long and pull two meters long, there is no difference in tension
The spring of the tape measure is very thin, and the amount of deformation when it is tightened is also small, so the reaction force is very small, and the force change is not felt when the rule is pulled.
Campus Card uses computer technology, network technology, and communication technology to comprehensively digitize all information resources related to educational administration, school affairs management, and life services, and uses scientific and standardized management to integrate and integrate these information resources to form a unified User management, unified resource management and unified access control.