Glossary Terms
Terms that are used on the Manufacturing Automation website
D/A
Converter Short for digital-to-analog converter. This is a device that
changes a digitally coded word into its equivalent quantized analog
voltage or current. Just like the A/D device, there are very high-speed
D/A’s available, capable of converting at data rates up to 1 GHz.
Dark factory
A completely automated factory floor with no labour.
Data
all information of computer operations directed by the detailed instructions of the program.
Data acquisition system
any instrument or computer that acquires data from sensors via
amplifiers, multiplexers, and any necessary analog to digital
converters.
Data collection
the act of bringing data from remote points to a central location, and its organization into understandable information.
Data element
A single, atomic piece of data that cannot be subdivided and still
retain any meaning. The terms "data item" and "field" are often used
synonymously with data element.
Data Management
The process by which the reliability, timeliness and accessibility of an organization??s data base is assured.
Data space
where data reside.
Data warehouse
A database for query and analysis, as opposed to a database for
processing transactions. Separating the two functions improves
flexibility and performance.
Database
a collection of structured information.
dB (Decibel)
20 times the log to the base 10 of the ratio of two voltages. Every 20
dBs correspond to a voltage ratio of 10, every 10 dBs to a voltage
ratio of 3.162. For instance, a CMR of 120 dB provides voltage noise
rejection of 1,000,000/1. An NMR of 70 dB provides voltage noise
rejection of 3,162/1.
DBMS
Database Management Systems access data stored in a database and
present multiple data views to end users and application programmers.
DC
Direct current; an electric current flowing in one direction only and substantially constant in value.
DCOM
Distributed COM
DCS
Distributed Control System is a real-time control system for continuous and batch process applications.
Deadband
In process control, a range in which an input signal may be varied, without initiating a change in output signal.
Decibel
A unit (dB) for measuring the relative strength of signal power. The
number of decibels equals ten times the logarith (base 10) of the
ration of the measured signal power to a reference power. One tenth of
a bell.
Decision
support tools PC-, client-, or application server-based systems that
use memory-based processing to perform rapid simulations using data
drawn from business-transaction processing systems such as enterprise
resources planning. The simulations optimize such things as production
or distribution plans based on variously weighted goals, such as low
cost or on-time delivery. Management then can decide which scenario
best balances the many competing claims it must address when running a
business.
Default value
The option taken by a computer in the event of the omission of a definite instruction or action.
Demand
Level of power supplied from the electric system during a specific period of time.
Demand management
see Forecasting.
Demand-side management (DSM)
Measures taken by a utility to influence the level or timing of a
customer’s energy demand. By optimizing the use of existing utility
assets, DSM programs enable utilities to defer expenditures for adding
new generating capacity.
DEP
Design and engineering practice
Deployment
The systematic process of introducing an activity or process to all applicable areas of an organization.
Deterministic model
A mathematical model that, given a set of input data, produces a single output or a single set of outputs.
Development tools
The raw materials by which programmers create custom-built enterprise software.
Deviation
The difference between an observation and a fixed value.
Device driver
Software that controls a computer peripheral, sometimes referred to as the interface software.
Differential
For an on/off controller, it refers to the temperature difference
between the temperature at which the controller turns heat off and the
temperature at which the heat is turned back on. It is expressed in
degrees.
Digital Output
An output signal which represents the size of an input in the form of a series of discrete quantities.
DIN
A set of German standards recognized throughout the world. The 1/8 DIN
standard for panel meters specifies an outer bezel dimension of 96 x 48
mm and a panel cutout of 92 x 45 mm.
Discrete event simulation
A technique often used by engineers in the design and modification of
production systems, whereby models output statistical estimates of
performance, using graphic animation to help create a greater
understanding of system dynamics.
