josh@polaris.UUCP (Josh Knight) (07/10/85)
%A W.E. Langlois
%T The Dynamical Equations Governing A Lubricating Film
Consisting of a Gas Film Overlying a Liquid Film
%J IBM J R&D
%V 29
%N 1
%P 2-10
%D JAN 1985
%X The dynamical equations governing a two-phase lubricating configuration
are derived. It is assumed that a gas film overlies a liquid file,
both thin enough that the lubrication approximation may be used.
The analysis leads to coupled Reynolds equations governing the pressure
and the relative thickness of the two films. The coupling, which is
determined by continuity of tangential stress across the glass-liquid
interface, is considerably simplified if the shear viscosity of the
liquid greatly exceeds that of the gas.
%A Derek Y.C. Chan
%A Douglas Henderson
%A Jorge Barojas
%A Andrew M. Homola
%T The Stability of a Colloidal Suspension of Coated Magnetic
Particles in an Aqueous Solution
%J IBM J R&D
%V 29
%N 1
%P 11-17
%D JAN 1985
%X Expressions for the magnetic, electrostatic and van der Waals interactions
between isolated magnet spheres which are coated with an inert material and
immersed in an aqueous electrolyte solution are obtained and used to study
the stability of a colloid of spheres in an electrolyte. Use is made of a
simplified version of the theory of colloid stability of Derjaguin, Landau,
Verwey, and Overbeek. We find that the colloidal dispersion becomes more
stable as 1) the electrolyte concentration is decreased, 2) the radius of
the magnetic spheres is decreased, or 3) the thickness of the inert layer
is increased. In order to obtain stability with uncoated spheres, the spheres
should have radii of about 5nm. Such radii are typical of ferrofluids.
%A L.L. Marsh
%A D.C. Van Hart
%A S.M. Kotkiewicz
%T A Dielectric Loss Investigation of Moisture in Epoxy-Glass Composites
%J IBM J R&D
%V 29
%N 1
%P 18-26
%D JAN 1985
%X Dielectric loss has been used to study moisture absorption-desorption
equilibria and kinetics in epoxy-glass composites. Measurements were made
at a temperature of 90 degrees C and a frequency of 200 Hz to maximize
sensitivity to interfacial or Maxwell-Wagner polarization. Exposure to
various partial pressures of moisture at that temperature permitted a
kinetics analysis from which an estimate was made of the diffusivity of
water in the composites. Values of dielectric loss at saturation were
used to establish a moisture/dielectric loss calibration at 90 degrees C
which can be used to estimate the macroscopic internal moisture content
of coupon samples and printed circuit cards and boards. Dielectric loss
measurements offer promise as a screening technique for resin-glass coupler
development.
%A J.M. Atkinson
%A R.D. Granata
%A H. Leidheiser, Jr.
%A D.G. McBride
%T Cathodic Delamination of Methyl Methacrylate-based Dry Film Polymers
on Copper
%J IBM J R&D
%V 29
%N 1
%P 27-36
%D JAN 1985
%X Studies of the bond degradation between a laminated organic coating and a
copper substrate have been carried out using electrochemical techniques.
The failure of the bond is attributed to a cathodic reaction which occurs
under the coating. The rates of delamination are shown to be affected
by delay time after exposure, temperature, applied potential, composition of
the electrolyte, and surface abrasion prior to application of the coating.
%A James A. Brown
%T A Development of APL2 Syntax
%A James A. Brown
%J IBM J R&D
%V 29
%N 1
%P 27-48
%D JAN 1985
%X This paper develops the rules governing the writing of APL2 expressions
and discusses the principles that motivated design decisions.
%A N. Takagi
%A C.K. Wong
%T A Hardware Sort-Merge System
%J IBM J R&D
%V 29
%N 1
%P 49-67
%D JAN 1985
%X A hardware sort-merge system which can sort large files rapidly is
proposed. It consists of an initial sorter and a pipelined merger. In
the initial sorter, record sorting is divided into two parts: key-pointer
sorting and record rearranging. The pipelined merger is composed of
several intelligent disks each of which has a simple processor and some
buffers. The hardware sort-merge system can sort files of any size by
using the pipelined merger repeatedly. The key-pointer sorter sorting
circuit in the initial sorter requires neighboring cells, instead of the
usual bidirectional ones. The initial sorter can also generate sorted
sequences longer than its capacity so that the number of merging passes
can be reduced. A new data management scheme is proposed to run all
merging passes in a pipelined fashion.
%A Lawrence V. O'Malley
%T Adaptive Clustering Algorithm
%J IBM J R&D
%V 29
%N 1
%P 68-72
%D JAN 1985
%X Output data from many types of sensor systems (radar, radar warning,
sonar, electro-optical, etc.) must be associated with one or more possible
sources based on multiple observations of the data. This paper presents an
algorithm that associates data with their source by simultaneous n-dimensional
clustering of multiple data observations. The algorithm first orders the
observations by successive nearest neighbor, in the n-dimensional Euclidean
sense, from a defined starting point. Clusters are then isolated using a
method derived from statistical decision theory. The algorithm's primary
feature is its ability to perform clustering adaptively without any
assumptions about the size, number, or statistical characteristics of
the clusters. Since the algorithm was developed for radar warning system
processing, a performance comparison with a well-known algorithm used
in that field is included.
%A Jon R. Mandeville
%T Novel Method for Analysis of Printed Circuit Images
%J IBM J R&D
%V 29
%N 1
%P 73-86
%D JAN 1985
%X To keep pace with the trend towards increased circuit integration,
printed circuit patterns are becoming denser and more complex. A variety
of automated visual inspection methods to detect circuit defects during
manufacturing have been proposed. This paper describes a method which
is a synthesis of the reference-comparison and the generic-property
approaches that exploits their respective strengths and overcomes their
respective weaknesses. It is based on the observation that the local
geometric and global topological correctness of a printed circuit can
be inferred from the correctness of simplified, skeletal versions of
the circuit in a test image. These operations can be realized using
simple processing elements which are well suited to implementation
in hardware.
%A C.H. Stapper
%T The Effects of Wafer to Wafer Defect Density Variations on Integrated
Circuit Defect and Fault Distributions
%J IBM J R&D
%V 29
%N 1
%P 87-97
%D JAN 1985
%X A method for modeling the variations in defect levels in circuits
produced on modern integrated circuit manufacturing lines is described
in this paper. The effects on defect and fault distributions are derived.
A deficiency in some previous yield models is eliminated.
------
Josh Knight, IBM T.J. Watson Research
josh at YKTVMH on BITNET, josh.yktvmh.ibm-sj on CSnet,
...!philabs!polaris!josh