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Identification and classification systems There are so many pieces of engineering information that special identification and classification systems have to be used to keep track of them. Unique numbers are needed to identify every specification, drawing, list, test procedure, operating manual, etc. which defines the functionality, physical construction, and/or performance of a product, component, assembly, sub-assembly, or part. Status Engineering data can be in various states (e.g., in-process, in-review, released, as-designed, as-planned, as-built, as-installed, as-maintained, and as-operated). Different rules apply to access and modification of data in different states. In early stages of a design, data is frequently modified, whereas once it has been released it is much more stable. Users may need to work with data that are in different states. Change Most engineering data undergoes change at various times in its lifetime. The management of these changes introduces added complexity to the engineering data management process. Changes to data have to be formally requested, evaluated and properly approved by all interested parties. Changes have to be publicized and recorded. Sources Engineering data is created in many functions, and is used in many functions. Some engineering data is created within the engineering function, some is created elsewhere. Some of the data is used within the engineering function, some is used elsewhere. Some of the data will be created in the company, some will be created by suppliers and customers. Whichever source it comes from, it has to be managed. Users Engineering data will be used by many people in many different functions and at many different locations. They may be working on the company's premises. They may be working for a supplier, a partner, or they may even be the final customer of the company's product. Data has to be made available to all these people. At the same time, data must be protected against unauthorized access. There will be many users of data. A given piece of information may be created by a design engineer, analyzed by another engineer, drafted by someone else, checked by a supervisor, and scrutinized by a manufacturing engineer even before it is accepted as potentially useful. Uses Users of engineering data will be working on a variety of tasks. Depending on what they are doing, and their level of computer literacy, they will have different data usage and data management needs. Some will create data, and some will modify it. Others will only want to reference data, perhaps for management purposes. Many of the users will have an engineering background, but those outside Engineering will probably come from other backgrounds such as accountancy, marketing and sales. Locations The users of engineering data may be in the same building, or in the same plant, but they could also be in locations in different countries, or even on different continents. Data will be distributed over several locations. Copies of each individual data item will be held in several stores. Wherever the data is, it needs to be managed. Departmental organizations Engineering data will be used and shared by several departments. A lot of engineering information will be created in the Engineering Department, but information will also be created and used in the Manufacturing, Marketing, Finance, Sales and Maintenance Departments. Some of the data will be with design engineers, some with manufacturing engineers, some with production planners, some on the shop floor. Some data will be with the customer, and some with suppliers. Wherever the data is, and whoever it is with, it needs to be managed if it is to be used effectively. Views Different users will want to see different views of the data. Many users will only want to see and work with one view of the data. For example, a project engineer may want to check an assembly of parts, but have no interest in stress or thermodynamic analysis results related to the assembly. A drafter may only be interested in an individual part of the assembly. The company may only want to give a supplier a very restricted view of the assembly. In all these cases, while users may want to see different views of the data, and the systems they use may be different, the underlying data must be the same. The available views of a product change during its lifetime. In early stages of development, the product is defined in specifications describing its functionality and required performance. Later in the development cycle, a top-level design is prepared which assigns specific functions to specific parts of the product. Towards the end of the design process, the physical arrangement of these parts is fully described, through detailed engineering drawings and parts lists. Information is generated to support the processes of production and test of the product. Information is also prepared to support the product in operational use, and, once it has been built, information on its actual performance in the field will be measured and recorded. Computer programs Engineering data is created and used by many different computer programs in the engineering environment. Examples include CAD, NC, finite element analysis, process planning, technical publishing, word processing, and test systems. These systems create and work with engineering data in different ways. Each one will probably have its own specific approach to data management. Each will primarily address the function it is supposed to perform, such as geometry definition, or technical publication, with data management being a secondary (and ineffectively implemented) function. These systems typically focus on activity-specific functions. They create data, but neglect data management functions such as data definition, structuring, organization, storage, retrieval, archival, communication, exchange, protection, distribution and tracking. Computers To process engineering data, most companies will use computers of various sizes from different vendors. In some cases there may be a supercomputer and one or more mainframes in use. There will be a variety of Personal Computers, Engineering Workstations and servers. There may be some dumb graphics terminals with little computing power. Some of the computers will be stand-alone, some will be linked together on a Local Area Network (LAN). Others will be linked together on other networks - Metropolitan Area Networks (MAN), Wide Area Networks (WAN), and Global Area Networks (GAN). Engineering data will be created and used on computers that run on different operating systems. Some of these will be proprietary. Others will, in principle, conform to a standard, such as UNIX. However, even those that are, in principle, standardized may have minor differences, particularly between different versions and releases. Whatever the computer, network or operating system, data has to be managed. |