Page 325 - Electrical Engineering Dictionary

Gibson mix an analysis of computer ma- glass laser laser in which the host medium
chine language instructions that concluded for doping with laser atoms is a glass.
that approximately 1/4 of the instructions ac-
counted for 3/4 of the instructions executed glitch (1) an incorrect state of a signal that
on a computer. lasts a short time compared to the clock pe-
riod of the circuit. The use of “glitch” in de-
GIF See Graphics Interchange Format. scribing power systems is generally avoided.
See also hazard.
gigaflop (GFLOP) 1000 million floating (2) slang for a transient that causes equip-
point operations per second. ment crashes, loss of data, or data errors.

Gilbert cell a four-transistor configura- global alignment a method of alignment
tion combining the differential pair and cur- where the mask is aligned globally to the
rent mirror concepts. With appropriate sig- whole wafer (as opposed to field-by-field
nal conditioning at the input and output ter- alignment).
minals, the cell can be used for many analog
signal processing applications such as analog global interconnection interconnection
multiplication. in which every source is connected to all
detectors and every detector is connected to
Gilbert, William (1544–1603) Born: all sources. Global interconnection is easily
Colchester, Essex, England implementable using optics because, unlike
Gilbert is best remembered as an early electrons, photons do not interact with each
investigator into electric charge and mag- other, and an optical system is inherently a
netism. He is also considered by many parallel processor.
to be the inventor of the modern scientific
method. This is due to his rigorous experi- global memory in a multiprocessor sys-
mentalmethodology, andthedetailedrecords tem, memory that is accessible to all pro-
he kept on his investigations. Isaac New- cessors. See also local memory, distributed
ton and Francis Bacon both acknowledged memory.
his contributions in this regard. Gilbert was,
by training, a physician and held the post of global minimum a point at which a func-
royal physician in the courts of Elizabeth I tion attains its lowest value over the domain
and James I. of its arguments.

global observability of generalized 2-D
Givens transformation a transformation,
model the generalized 2-D model
proposed by Givens, that transforms a gen-
eral matrix to a triangular form. The Givens
Ex i+1,j+1 = A 1 x i+1,j + A 2 x i,j+1
transformations G ijθ are functions of three
parameters. Transforming a vector b, a = + B 1 u i+1,j + B 2 u i,j+1
G ijθ b; then a n = b n for all n 6= i, n 6= j, y ij = Cx ij
and the two-vector [a i a j ] is equal to the ro-
tation of vector [b i b j ] by an angle θ in the is called globally observable if any of its
plane. Givens rotations can be used to suc- global semistates
cessively set elements of a matrix to zero by

an appropriate selection of ijθ. X(q) := x i−q,−i ,i = ..., −1, 0, 1,... ;
q = 0, 1,...}
GKS See graphical kernel system.
can be calculated using future outputs and
GLA See generalized Lloyd algorithm. inputs of the model, i.e.,

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2000 by CRC Press LLC