Application and Analysis of XML-based JDF in Printing Digital Workflow (I)

Abstract: JDF (Job Definition Format) is a comprehensive XML-based file format that combines information description tags and information transfer protocols to provide industry standards for end-to-end work specification; XML is JDF and CIM (Computer Integration) Manufacturing) pillar technology. This article introduced the current status of the development of XML and XML-based JDF formats, and then introduced the key technologies for the integration of production process chains using XML-based JDF. Finally, the development trend of this research field was analyzed.

Keywords: Job Definition Format (JDF), XML System Integration, Workflow, CIP4, Workflow Management, Job Tracking

introduction

Over the years, the production of the printing industry has undergone dramatic changes. For a long period of time, all production has been manual, and then mechanization has led us to the road to automation. We have now owned an efficient automated production system. However, currently, in most production environments, the exchanges between devices are still insufficient, and the processing process is not smooth enough. In order to adapt to the changes in the current market, industrial production faces the following trends:

The shortening of the work cycle requires a flexible response to the increased complexity of the job

The increase in automation requires that production engineering be more efficient, flexible and transparent. When we have effective automatic control, we naturally need a work summons. Using the information provided by subpoenas, production can be more efficient.

All supply chain integration within and outside the company can be realized through JDF. The integration of modern network and database technology can achieve high input-output ratio. Such an integrated system can enhance the availability of data and reduce preparation time. , To shorten the production cycle and increase production flexibility, which provides facilities for equipment providers, producers and customers.

In the fierce global competition, the printing and publishing industries have successively applied a series of process application software to improve the management level and production capacity of enterprises. However, these softwares cannot communicate with each other and form an isolated island of information. The important reason is that the cooperation between different suppliers is only on a very limited basis. It takes time to coordinate different productions. Business equipment. Although the XML language has the ability to encode multiple languages, it is not entirely applicable.

Moreover, in the printing workflow, the biggest and most important obstacle is the communication between the management information system (MIS) responsible for planning and control work and the production service system responsible for the operation. In other words, there is no automatic, coordinated, effective two-way communication between these two aspects. All the data that lists the plans, arrangements, processing results, work status and job tracking must be passed from the production department to the MIS. The MIS can then provide a job instruction after processing the information. This is still a manual process. Now that we have a complete set of processes that are composed of various equipment functions and all the necessary conditions for the completion of jobs, we cannot integrate them into a coherent whole. The so-called digital unity of cash is the patchwork of this piecemeal, efficiency. Very low, it will eventually be abandoned by the digital age.

Everything is available, but only the east wind. The development of the industry has entered the direction of normalization, standardization, and automation from the traditional human-oriented mode of production. In July 2000, CIP3 was renamed CIP4 and the CIP4/JDF standard was established. CIP4 is an abbreviation for "International Cooperation for Processes in Prepress, Press and Post-press." JDF is the "Job Definition Format". . The JDF launched by CIP4 focuses on the integration of information and financial, accounting, and MIS (Management Information System) information in all aspects of the printing process to achieve computer integrated management (CIM) in the entire printing process. Printing companies that apply the JDF process will implement a fully automated process of quoting, picking up, work order scheduling, production, work order tracking, product shipment, invoice creation, and collection. JDF (Job Definition Format) is a comprehensive XML-based file format that combines information description standards and information transfer protocols to provide industry standards for end-to-end work practices.

XML is the standard of data exchange recommended by the W3C. Its development started in 1996. The printing and publishing industry also needs a complete and powerful standard to support e-commerce, automation, and CIM, and it must be able to unite various printing processes. , which ultimately contributed to the creation of an XML-based JDF file format. However, what are the technical features of XML and JDF that make it the industry standard? Let's do some analysis below.

Extensible Markup Language Technical Analysis

XML is data-oriented. It supports user-defined tags. It organizes data through nested elements that satisfy certain logical relationships. XML document tags only describe the contents of text files, and do not describe how to display and output formatting information. . The application can identify the tags in the XML document and process the exchange criteria according to the semantics of the tags. Below we analyze XML as a JDF basis to describe some features of the production process and information exchange:

XML has some characteristics of the process description language;
(1) XML is a tag-centric self-describing language;
(2) The ordering of XML can indicate the sequence between activities;
(3) The inherent cascade structure of XML can intuitively represent the parent-child relationship between activities, and the JDF tree structure to achieve data connection.

XML and Java technology

XML and Java technologies have many complementary features. The combination of the two will form a powerful platform for data sharing and processing. On the one hand, XML can define data and documents in an open and neutral way, and of course, also develop those that can handle The application of these data or documents; on the other hand, the Java platform provides a unified computing environment, in particular portable Java code can be downloaded to any Java virtual machine via the network, and the combination of XML and Java technology. Based on their inherent collaboration.

The XML-based data exchange format (architecture shown in Figure 1) has the following outstanding advantages:

(1) Self-describing, extensible and linguistic features can be added, making the meaning of the data very intuitive;
(2) Create more intelligent documents with the help of DTD/XML Schema;
(3) Has a standard, unified, and universal parser interface that avoids the limitations of specific document formats;
(4) If the meaning of the mark is not clear enough and sufficient, it can be freely annotated without affecting the interpretation of the document;
(5) Under the premise of conforming to the DTD specification, the order of data in the document can be adjusted as needed without affecting the resolution of the document;
(6) Through the query interface (self-developed or commercial software XQL, XML-QL, etc.), it is convenient to query and extract semantically-featured data satisfying the user's needs in large XML documents;
(7) In combination with XSL, it is convenient to display certain data in a specific style according to requirements;
(8) There is a good interface with the database, large quantities of XML documents can be stored and managed using the database.