348 Engineering Fundamentals
D
database: A structured system of storing data in
a computer system. (12)
design brief: The document that guides the
design process and includes constraints, such
as size, cost, and quality. (2)
design engineer: An engineer who uses an
engineering design process to create a
product that meets the needs of a client. (16)
destructive material test: A test that destroys
a material or somehow makes a material
unusable. (7)
detail drawing: A type of working drawing that
shows the exact shape and size of an object
and includes specifi c dimensions. (2, 5)
development engineer: An engineer who is
involved in the testing and analysis of ideas
and products. (16)
differential balance: A type of balance that is
taken at the same point over time. (15)
differential pressure fl owmeter: A type of
fl owmeter that constricts the fl ow by
placing some sort of obstruction inside of
a pipe or by narrowing the pipe at a point.
As the fl uid goes around the obstruction
or through the narrow point, it speeds
up and its pressure decreases. Flow rate
is determined using the pressure at the
obstruction or narrow point and away from
that point. (15)
digital signal processing: The processing of
signals that are represented by 1s and 0s. (12)
dihedral angle: The upward angle of wings
away from the body that creates stability. (13)
dimensioning: A process used to describe the
size of an object as well as the location of
different features of a design. (5)
diode: A component that limits current fl ow to
one direction. Can be used as rectifi ers to
change ac to pulsating dc. (8)
direct current (dc): Current fl ow in one
direction, where polarity never changes. (8)
discussion forum: An area on the Internet where
a person can type a question or comment
and other people can answer the question or
comment on the original message. (4)
DNA fi ngerprinting: A method used by forensic
scientists to identify humans by their genetic
makeup. (11)
drag: The force created by the friction of moving
air that opposes propulsion. (13)
drilling: The act of cutting a circular hole down
into the earth to extract things like water,
natural gas, oil, and other materials from
under the earth’s surface. (14)
dynamic load: A sudden impact on the
structure. (9)
dynamics: The study of forces that cause motion
on physical objects. (9)
E
economic impact: The effect on fi nancial
systems, such as the profi t that is made for
an engineering project. (16)
elasticity: The ability to return to the original
dimensions if the stress is removed. (7)
electrical engineering: The design and
construction of electrical and electronic
components and devices. (1, 8)
electricity: The movement of electrons. (8)
electrode: A solid conductor through which
electricity enters or leaves a medium. (8)
electron: A negatively charged subatomic
particle. (8)
electronic distance meter (EDM): A part of the
total station, emitting infrared light. (9)
elevator: A control surface located on the rear of
the horizontal stabilizer that controls vertical
movement of the nose. (13)
end-of-arm tooling: The ability for a variety of
tools to be attached to the end of a robotic
arm. Examples include paint spray guns,
welders, and grippers. (12)
energy: The ability to do work. (10)
engineer: A highly trained professional who uses
both knowledge and skills to solve problems. (1)
engineering: The use of mathematics, science,
and technology to create products and
systems that improve the world. (1)
engineering design: The creative application of
technology to design a system, product, or
process to solve a given problem or meet a
given need. (2)