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The term 'Engineering Data' includes all data related both to a product and to the processes that are used to specify, develop, produce and support it. Examples of engineering data include specifications, schedules, process plans, technical manuals, project plans, Bills of Materials, descriptive geometry, formulae, test and quality results, results of analytic experiments and calculations, computer programs, photographs, drawings, sketches, video data and voice data. Some engineering data (e.g., part geometry) is created within the engineering function, some is created elsewhere (e.g., in field tests). Some of the data (e.g., stress or circuit analysis results) is used within the engineering function, some (e.g., welding instructions) is used elsewhere. Engineering data can be found in many locations and on many media. There is a lot of it (some companies have many hundred thousand documents and many million megabytes of data). It comes in many forms (e.g., numeric, graphic, alphanumeric). Some of the users of data will be inside a company, others outside (e.g., suppliers and customers). Engineering data is used in many activities throughout the life cycle of a product. The expression 'product life cycle' refers to the stages a product moves through as it evolves from a concept through development and production to operational use, obsolescence and recycling. Definition The term 'Engineering Data' encompasses all data related both to a product and to the processes that are used to design, produce and support it. Scope Engineering data includes a very wide range of information such as specifications, schedules, process plans, manuals, project plans, geometry, formulae, results of analytic experiments and calculations, computer programs, photographs, drawings, sketches, video data and test result commentaries. Media Engineering data are on a variety of media. In a typical Engineering organization, some of the data will be on traditional media such as paper and aperture cards. Some will be on electronic media. Some may be on an Intranet. Some may be on the Web. Some data may be on mylar or microfilm. Some may be on paper tape. Some data may be on magnetic tape. Some may be on magnetic disk, some on optical disk. Due to the diversity of computers, operating systems, storage devices and storage techniques, there are many differences between the various electronic media. Data on different media have to be managed in different ways. Type and format Engineering data exists in many forms. There is text data, numeric data, graphics data and voice data. Within each of these types of data, there may be differences. For example, some of the graphics will be in vector form, some will be in raster form. The materials on which data are stored will be of different sizes. Paper will be of various sizes, probably ranging from the US A-size (European equivalent A4) to the US E-size (European equivalent A0). Tapes will range in size from small disks up to devices with many GB. Some of the data that needs to be managed will actually be computer programs. Among the programs that need to be managed are both those that are linked to products (programs developed to be used within the company's products), and those that are linked to processes (programs such as CAD, CAM and ERP that support the company's operations). Representations Information may be represented in different ways. For example, a circle may be represented by three points on its circumference in one CAD system, but by its center and radius in another CAD system. A line may be represented by a vector in a CAD system, but by a set of points in a rasterized representation. Data exchange As data may be represented in different ways in different systems and media, there may be problems when it is transferred from one representation to another. An exact conversion may be impossible, with the result that a loss of quality will occur. Structure A product, or a plant, may be made up of assemblies, sub-assemblies, components and parts. Data, such as Bills of Materials and goes-into lists describe the structure and relationships. This data has to be managed. Options Many products, such as cars, are available in a variety of options. The descriptions of each option have to be managed. As product lifetimes decrease and customization increases, the number of options will increase, as will the required management effort. Versions of information Different versions of the same information will exist. In some cases, a user may need the latest version. In other cases an earlier version may be needed. People who need the latest version want to be sure that the version they receive really is the latest, and not an out-of-date or superseded version. Versions of systems Computer software is regularly upgraded. Each time a system is upgraded, there is the risk that the addition of new functionality and a richer information content will make it impossible to access and use information created in previous versions of the system. |