NASA Scientific and Technical Aerospace Reports

value of the error signal in the coefficient update equation. It is found to be easy to implement and gives advantages over the
conventional algorithm under certain conditions.
Author
Least Squares Method; Mean Square Values; Algorithms; Very Large Scale Integration; Signal Processing
20060002167 Naval Postgraduate School, Monterey, CA, USA
A Recursive Least Squares Algorithm for Gray-Markel Lattice
Tummala, Murali; Parker, Sydney R.; 1987 IEEE International Symposium on Circuits and Systems, Volume 2; 1987,
pp. 436-441; In English; See also 20060002103; Copyright; Avail.: Other Sources
This paper derives a new recursive least squares algorithm for a 2-multiplier Gray-Markel lattice filter realizing an infinite
impulse response (IIR) transfer function. The algorithm consists of two parts - updating the lattice reflection coefficients, and
updating the filter tap weights. The proposed algorithm differs from those presented previously in that it does not incorporate
a gradient approximation step in its derivation. Also the absence of an adaptation constant, that usually requires a trial and error
selection, makes it a more robust algorithm at the expense of more computations. In the following, we present a detailed
derivation of the algorithm together with computer simulation results showing its faster rate of convergence.
Author
Transfer Functions; Algorithms; Computerized Simulation; Gradients; Lattices; Convergence
20060002170 Zhejiang Institute of Technology, Hangzhou, China
An Application of Bin-Packing to Building Block Placement
Chun-hong, Chen; Mei-lun, Liu; 1987 IEEE International Symposium on Circuits and Systems, Volume 2; 1987, pp. 576-579;
In English; See also 20060002103; Copyright; Avail.: Other Sources
More and more attention has been paid to building block placement (BBP) problem in the automatic layout design of
VLSI. This paper describes an application of bin-packing to BBP which is based on a kind of classification of blocks. The
algorithm tries to minimize the chip size required while the routing is facilitated, and provides a new approach to the
constructive initial BBP. Experimental results have shown the excellent performance of the algorithm.
Author
Algorithms; Very Large Scale Integration; Automatic Control
20060002171 Northeastern Univ., Boston, MA, USA
Graph Partitioning Approach to Speech Decoding
Venkatesh, C. G.; Deller, J. R., Jr.; Cozzens, M. B.; Hsu, D.; 1987 IEEE International Symposium on Circuits and Systems,
Volume 2; 1987, pp. 580-583; In English; See also 20060002103; Copyright; Avail.: Other Sources
A partitioning theorem for planar graphs due to Lipton and Tarjan is applied to a class of decoding problems. A graph
consisting of N nodes can be searched for an optimal decoding path using only O(/N) node evaluations and with less risk of
pruning the correct path than with conventional methods. An example application to speech recognition is given.
Author
Decoding; Speech Recognition; Mathematical Models; Graphs (Charts)
20060002172 Illinois Univ. at Urbana-Champaign, Urbana, IL, USA
JADE: A Hierarchical Switch Level Timing Simulator
Lai, Feipei; Rao, Vasant B.; Trick, Timothy N.; 1987 IEEE International Symposium on Circuits and Systems, Volume 2; 1987,
pp. 592-595; In English; See also 20060002103; Copyright; Avail.: Other Sources
JADE is a hierarchical switch-level timing simulator for CMOS circuits written in LISP. The entire circuit is first
partitioned inlo various blocks at each level of the hierarchy. The signal delays in JADE are computed hierarchically on a
block-by-block basis. Strongly connected components are deleeled and collapsed into a single vertex thereby resulting in a
directed acyclic condensation graph. JADE then simulates the blocks corresponding to the veriices of the condensation graph
in topological order. JADE then computes two parameters for each circuit node, namely, the earliest starting time computed
by scanning the vertices of the condensation graph lhe forward order and the latest completion time oblained by scanning in
the reverse order. A node is said to be critical if both parameters are equal. A block is said to be critical if it has a critical input
node and a critical outpul node. A critical path is then defined to be the longest directed path in the graph composed only of
critical blocks and/or subcircuits. The hierarchical approach used in JADE saves a considerable amount of memory space and
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