Page 99 - Electrical Engineering Dictionary

mode state estimator. For example, a bound- boundary scan test a technique for
ary layer version of the discontinuous con- applying scan design concepts to con-
troller trol/observe values of signal pins of IC com-
ponents by providing a dedicated boundary-
u =−Us(e)/|s(e)|=−Usign(s(e)),
scan register cell for each signal I/O pin.
where e is the control error and s is a function
boundary value problem a mathemat-
of e, may have the form
ical problem in which the unknown is a so-

−Usign(s(e)) if |s(e)| >ν lution to a partial differential equation and is
u =
−Us(e)/ν if |s(e)|≤ ν, subject to a set of boundary conditions on the
problem domain.
where ν> 0 is called the boundary layer
width.
boundary values of 2-D general model
let x i,j be a solution (semistate vector) to the
boundary layer controller See boundary
2-D generalized model
layer.
x i+1,j+1 = A 0 x i,j + A 1 x i+1,j
boundary layer observer See boundary
layer state estimator. + A 2 x i,j+1 + B 0 u i,j
+ B 1 u i+1,j + B 2 u i,j+1
boundary layer state estimator a con-
tinuous version of a sliding mode type state i, j ∈ Z + (the set of nonnegative integers)
m
estimator, that is, a sliding mode type state where u i,j ∈ R is the input and A k , B k (k =
estimator in which the right-hand side of the 0, 1, 2) are real matrices of the model. The
n
differential equation describing the estima- vectors x i,j ∈ R whose indices lie on the
tor is continuous due to the introduction of a boundary of the rectangle [0,N 1 ] × [0,N 2 ],
boundary layer to smooth out the discontin- i.e., x i,0 , x i,N 2 for 1 ≤ i ≤ N 1 and
uous part of the estimator’s dynamics. x 0,j ,x N 1 ,j for 0 ≤ j ≤ N 2 , are called
boundary values of the solution x i,j to the 2-
boundary scan a technique for applying D general model. The boundary values may
scan design concepts to control/observe val- be also given in other ways.
ues of the signal pins of IC components by
providing a dedicated boundary-scan register boundary-element method (BEM) a nu-
cell for each signal I/O pin. merical method (integral equation technique)
well suited to problems involving structures
boundary scan interface a serial clocked in which the dielectric constant does not vary
interface used to shift in test pattern or test with space.
instruction and to shift out test responses in
the test mode. Boundary scan interface com- bounded control See saturating control.
prises shift-in, shift-out, clock, reset, and test
select mode signals. bounded distance decoding decoding of
an imperfect t-error correcting forward error
boundaryscanpath atechniquethatuses correction block code in which the corrected
a standard serial test interface to assure easy error patterns are limited to those with t or
access to chip or board test facilities such as fewer errors, even though it would be possi-
test registers (in an external or internal scan ble to correct some patterns with more than t
paths) or local BIST. In particular it assures errors.
complete controllability and observability of
all chip pins via shift in and shift out opera- bounded function a function x ∈ X e is
tions. said to be bounded if it belongs also to the

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2000 by CRC Press LLC