Enterprise Integration and Communications Systems

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(DISTRIBUTED AUTOMATION EDITION) An IBM software solution to provide tools and techniques that will enable factory floor applications programs to be written that are independent of the distributed data, local area network protocol terminal.
Data Flows
These are like pipelines that carry data between processes, data stores or external agents.
Data and Information
If we use the term data, we mean data to which relevance and semantics could be associated. The term information refers to data, to which the relevance and the semantics are already associated as indicated by the following hierarchy.
The values stored in a database are referred to as data. They become information only when associated with some definition of their meaning, purpose and relationship with other values. Normally, it is the user who synthesizes data to derive information that is meaningful. This synthesis can also be performed through the use of artificial intelligence.
Data Stores
Serve as repositories of data produced by processes. These data are then made available to other specified processes.
(DATABASE-2) - IBM's relational database. It runs on the MVS and OS/2 operating systems.
IBM's "strategic" product for general -purpose information storage, including database management. It is the product in the MVS environment that implements SOL, the SAA database programming interface. As such, DB2 is a key building block in IBM's entire software strategy.
A software package that enables end users or application programmers to share data. DBMSs are generally also responsible for data integrity, data access control and automated rollback/restart/recovery.
See Distributed Control System. Typically, a CRT-based shared logic control system, for use on medium to large-scale continuous and batch process plants.
DEC's version of the OSI MMS protocol to be used for control-level device communications.
Demand Management
The function of recognizing the managing all of the demands for products to ensure that the master scheduler is aware of them. It encompasses the activities of forecasting, order entry, order promising, branch warehouse requirements, inter-plant orders, and service parts requirements.
Dependent Demand
Demand is considered dependent when it is directly related to or derived from the demand for other items or end products. Such demands are, therefore, calculated and need not, and should not, be forecast. A given inventory item may have both dependent and independent demand at any given time.
Design Basis
Document that contains the basis of a design to allow further detailed engineering.
Design Practices
Engineering methods, standards, practices.
A purely graphical input device (i.e., a CAD/CAM CAE system digitizer for convening locations into storable electronic impulses) with a surface on which a location or a point is selected and then automatically converted into a digital x y coordinate suitable for transmission to a computer. A device for converting a signal of any type into a digital representation for storage in a computer or other related component or system.
Direct Digital Control (DDC)
The use of a digital computer to read dependant variables, and establish commands to the final control elements of multiple regulatory loops. While common in the early days of digital process control, DDC using large central computers is increasingly being replaced by DCS and SCADA control strategies.
Directory Service
The network management function that provides all addressing information required to access an application process.
A branch of knowledge or teaching. Training intended to produce a specified character or pattern of behavior. A state of order based on submission to rules and authority. A set of rules or methods.
The selecting and sequencing of available jobs to be run at individual workstations and the assignment of these jobs to workers.
Distributed Computing
Computing performed within a network of distributed computing facilities. The processors for this type of system usually function with control distributed in time and space throughout the network. Associated with the distributed process are distributed storage facilities.
Distributed Control System
A series of computer-based devices that operate in conjunction with each other on a variety of applications. These are usually (widely) separated throughout the system being controlled.
Distributed Processing
A data processing organizational concept under which computer resources of a company are installed at more than one location with appropriate communication links. Processing is performed at the user's location generally on a mini or micro-computer, and under the user's control and scheduling, as opposed to processing for all users which is done on a large, centralized computer system.
Distribution Constraints
Information which influences the choice of distribution channels including distribution channel priorities, alternates, availabilities, customer requests, procedures, and lead times.
An arbitrary boundary defined to limit the scope of an entity/relationship or other model.
Domain Expert
A domain expert contains the raw knowledge that a knowledge engineer uses to structure the knowledge to fuse and formulate the rule base. [DEC]. One whole is well versed on all aspects of a domain of knowledge.
Domain Knowledge Representation
The knowledge representation that is specific to the application. These may be compound knowledge representations. The advantage of domain specific representations is that they represent knowledge in the most natural form for the knowledge engineer and domain expert.