leff@smu.UUCP (Laurence Leff) (09/01/89)
change of system parameters. Multiple perspectives are used to
represent relative change values over intervals of time. Differential
analysis has been implemented, tested on a dozen examples, and proven
sound. Unfortunately, the technique is incomplete; it always
terminates, but does not always return an answer.
:aim 952
:author Guy E. Blelloch and James J. Little
:asort Blelloch, G.; Little, J.J.
:title Parallel Solutions to Geometric Problems on the Scan Model of
Computation
:date February 1988
:pages 32
:cost $3.25
:adnum AD-A192321
:keywords scan-model, parallel algorithms, Connection Machine
:abstract
This paper describes several parallel algorithms that solve geometric
problems. The algorithms are based on a vector model of computation --
the {\it scan-model}. The purpose of this paper is both to show how
the model can be used and to show a set of interesting algorithms,
most of which have been implemented on the Connection Machine, a
highly parallel single instruction multiple data (SIMD) computer.
:aim 953
:author Henry M. Wu
:asort Wu, H.M.
:title Scheme 86: An Architecture for Microcoding a Scheme
Interpreter
:date August 1988
:pages 40
:cost $3.25
:adnum AD-A201258
:keywords scheme interpreters, computer architecture, LISP machine
:abstract
I describe the design and implementation plans for a computer that is
optimized as a microcoded interpreter for Scheme. The computer
executes SCode, a typed-pointer representation. The memory system has
low-latency as well as high throughput. Multiple execution units in
the processor complete complex operations in less than one memory
cycle, allowing efficient use of memory bandwidth. The processor
provides hardware support for tagged data objects and runtime type
checking. I will discuss the motivation for this machine, its
architecture, why it can interpret Scheme efficiently, and the
computer aided design tools developed for building this computer.
:aim 954
:author Charles Rich and Richard C. Waters
:asort Rich, C.; Waters, R.C.
:title Formalizing Reusable Software Components in the Programmer's
Apprentice
:date February 1987
:pages 28
:cost $3.25
:adnum AD-A185843
:keywords reuse, Programmer's Apprentice, software, components, plan
calculus
:abstract
There has been a long-standing desire in computer science for a way of
collecting and using libraries of standard software components. The
limited success in actually doing this stems not from any resistance
to the idea, nor from any lack of trying, but rather from the
difficulty of choosing an appropriate formalism for representing
components. For a formalism to be maximally useful, it must satisfy
five key desiderata: expressiveness, convenient combinability,
semantic soundness, machine manipulability, and programming language
independence. The Plan Calculus formalism developed as part of the
Programmer's Apprentice project satisfies each of these desiderata
quite well. It does this by combining the ideas from flowchart
schemas, data abstraction, logical formalisms, and program
transformations. The efficacy of the Plan Calculus has been
demonstrated in part by a prototype program editor called the
Knowledge-based Editor in Emacs. This editor makes it possible for a
programmer to construct a program rapidly and reliably by combining
components represented as plans.
:aim 955
:author Harold Abelson and Gerald Jay Sussman
:asort Abelson, H.; Sussman, G.J.
:title The Dynamicist's Workbench: I, Automatic Preparation of
Numerical Experiments
:date May 1987
:pages 39
:cost $3.25
:keywords dynamics, symbolic computation, numerical methods
:abstract
The dynamicist's workbench is a system for automating some of the work
of experimental dynamics. We describe a portion of our system that
deals with the setting up and execution of numerical simulations. This
part of the workbench includes a spectrum of computational tools -
numerical methods, symbolic algebra, and semantic constraints. These
tools are designed so that combined methods, tailored to particular
problems, can be constructed
:aim 957
:author John Canny and Bruce Donald
:asort Canny, J.; Donald, B.R.
:title Simplified Voronoi Diagrams
:date April 1987
:pages 16
:cost $2.50
:keywords robot motion planning, collision avoidance,
computational geometry, Voronoi diagrams
:abstract
The Voronoi diagram has proved to be a useful tool in a variety of
contexts in computational geometry. Our interest here is in using the
diagram to simplify the planning of collision-free paths for a robot
among obstacles, the so-called generalized movers' problem. The
Voronoi diagram, as usually defined, is a {\it strong deformation
retract} of free space so that free space can be continuously deformed
onto the diagram. In particular, any path in free space can be
continuously deformed onto the diagram. This means that the diagram
is complete for path planning, i.e. Searching the original space for
paths can be reduced to a search on the diagram. Reducing the
dimensionn of the set to be searched usually reduces the time
complexity of the search. Secondly, the diagram leads to robust
paths, i.e. paths that are maximally clear of obstacles.
:aim 958a
:author Richard C. Waters
:asort Waters, R.C.
:title Obviously Synchronizable Series Expressions: Part I: User's
Manual for the OSS Macro Package
:date October 1987
:reference Revised March 1988.
:pages 106
:cost $4.50
:adnum AD-A190493
:keywords functional programming, looping constructs, program
optimization, series expressions, compilation
:abstract
The benefits of programming in a functional style are well known. In
particular, algorithms that are expressed as compositions of functions
operating on series/vectors/streams of data elements are much easier to
understand and modify than equivalent algorithms expressed as loops.
Unfortunately, many programmers hesitate to use series expressions,
because they are typically implemented very inefficiently. A Common
Lisp macro package (OSS) has been implemented which supports a
restricted class of series expressions, {\it obviously synchronizable
series expressions}, which can be evaluated very efficiently by
automatically converting them into loops. Using this macro package,
programmers can obtain the advantages of expressing computations as
series expressions without incurring any run-time overhead.
:aim 959a
:author Richard C. Waters
:asort Waters, R.C.
:title Obviously Synchronizable Series Expressions: Part II: Overview
of the Theory and Implementation
:date November 1987
:pages 50
:cost $3.75
:adnum AD-A192783
:keywords series expressions, looping constructs, compilation, program
optimization, functional programming
:abstract
The benefits of programming in a functional style are well known. In
particular, algorithms that are expressed as compositions of functions
operating on series/vectors/streamsof data elements are much easier to
understand and modify than equivalent algorithms expressed as loops.
Unfortunately, many programmers hesitate to use series expressions,
because they are typically implemented very inefficiently--the prime
source of inefficiency being the creation of intermediate series objects.
A restricted class of series expressions, {\it obviously
synchronizable series expressions}, is defined which can be evaluated
very efficiently. At the cost of introducing restrictions which place
modest limits on the series expressions which can be written, the
restrictions guarantee that the creation of intermediate series
objects is never necessary. This makes it possible to automatically
convert obviously synchronizable series expressions into highly
efficient loops using straightforward algorithms.
:aim 962
:author Thomas R. Kennedy, III
:asort Kennedy, T.R., III
:title Using Program Transformation to Improve Program Translation
:date May 1987
:pages 36
:cost $3.25
:keywords program translation, program transformations,
program analysis
:abstract Direct, construct by construct, translation from one high
level language to another often produces convoluted, unnatural, and
unreadable results, particularly when the source and target languages
support different models of programming. A more readable and natural
translation can be obtained by augmenting the translator with a
program transformation system.
:aim 965
:author Heinrich H. B\"ulthoff and Hanspeter A. Mallot
:asort B\"ulthoff, H.H.; Mallot, H.A.
:title Interaction of Different Modules in Depth Perception: Stereo
and Shading
:date May 1987
:pages 28
:cost $3.25
:adnum AD-A185607
:keywords stereo, shape from shading, depth perception
:abstract
A method has been developed to measure the perceived depth of computer
generated images of simple solid objects. Computer graphic techniques
allow for independent control of different depth queues (stereo,
shading and texture) and enable the investigator thereby to study
psychophysically the interaction of modules for depth perception.
Accumulation of information from shading and stereo and vetoing of
depth from shading by edge information have been found. Cooperativity
and other types of interactions are discussed. If intensity edges are
missing, as in a smooth-shaded surface, the image intensities themselves
could be used for stereo matching. The results are compared with
computer vision algorithms for both single modules and their
integration for 3D-vision.
:aim 966
:author Robert J. Hall
:asort Hall, R.J.
:title A Fully Abstract Semantics for Event-Based Simulation
:date May 1987
:pages 17
:cost $2.50
:adnum AD-A190560
:keywords event-based simulation, full abstraction, denotational
semantics
:abstract
This paper shows that, provided circuits contain no zero-delay loops,
a tight relationship, full abstraction, exists between a natural
event-based operational semantics for circuits and a natural denotational
semantics for circuits based on causal functions on value timelines.
The paper also discusses what goes wrong if zero-delay loops are allowed,
and illustrates the application of this semantic relationship to
modeling questions.
:aim 967
:author Robert J. Hall, Richard H. Lathrop, Robert S. Kirk
:asort Hall, R.J.; Lathrop, R.H.; Kirk, R.S.
:title A Multiple Representation Approach to Understanding the Time
Behavior of Digital Circuits
:date May 1987
:pages 14
:cost $2.50
:keywords multiple representation, temporal reasoning, event-based
simulation, digital circuits, simplification, behavioral models
:abstract
We put forth a multiple representation approach to deriving the behavioral
model of a digital circuit automatically from its structure and the
behavioral simulation models of its components. One representation
supports temporal reasoning for composition and simplification, another
supports simulation, and a third helps to partition the translation problem.
A working prototype, FUNSTRUX, is described.
:aim 970
:author Ed Gamble and Tomaso Poggio
:asort Gamble, C.; Poggio, T.
:title Visual Integration and Detection of Discontinuities: The Key
Role of Intensity Edges
:date October 1987
:pages 32
:cost $3.25
:adnum AD-A188012
Hughes
:keywords visual integration, Markov random fields, parallel
algorithms, surface reconstruction, discontinuities
:abstract
Integration of several vision modules is likely to be one of the keys
to the power and robustness of the human visual system. We suggest
that integration is best performed at the location of discontinuities
in early processes, such as discontinuities in image brightness,
depth, motion, texture and color. Coupled Markov Random Field models,
can be used to combine vision modalities with their discontinuities.
We derive a scheme to integrate intensity edges with stereo depth and
motion field information and show results from a Connection Machine
algorithm on synthetic and natural images. The use of intensity edges
to integrate other visual cues and to help discover discontinuities
emerges as a general and powerful principle.
:aim 973
:author T. Poggio and C. Koch
:asort Poggio, T.; Koch, C.
:title Synapses that Compute Motion
:date June 1987
:pages 13
:cost $2.50
:adnum AD-A190389
Psychology Division
:reference See {\it Scientific American}, vol. 255, 46-52, May 1987.
:keywords parallel processing, synapses, motion, biophysics of computation
:abstract Biophysics of computation is a new field that attempts to
characterize the role in information processing of the several
biophysical mechanisms in neurons, synapses and membranes that have
been uncovered in recent years. In this article, we review a synaptic
mechanism, based on the interaction between excitation and silent
inhibition, that implements a veto-like operation. Synpases of this
type may underlie direction selectivity to direction of motion in the
vertebrate retina.
:aim 975
:author Michael A. Gennert and Shahriar Negahdaripour
:asort Gennert, M.A.; Negahdaripour, S.
:title Relaxing the Brightness Constancy Assumption in Computing
Optical Flow
:date June 1987
:pages 25
:cost $3.25
:adnum AD-A187437
:keywords brightness constancy assumption, passive navigation,
smoothness constraint, optical flow
:abstract
Optical flow is the apparent (or perceived) motion of image brightness
patterns arising from relative motion of objects and observer.
Estimation of the optical flow requires the application of two kinds
of constraint: the flow field {\it smoothness constraint} and the {\it
brightness constancy constraint}. The brightness contancy constraint
permits one to match image brightness values across images, but is
very restrictive. We propose replacing this constraint with a more
general constraint, which permits a linear transformation between
image brightness values. The transformation parameters are allowed to
vary smoothly, so that inexact matching is allowed. We describe the
implementation on a highly parallel computer, and present sample results.
:aim 977
:author Sundar Narasimhan, David M. Siegel, and John M. Hollerbach
:asort Narasimhan, S.; Siegel, D.M.; Hollerbach, J.M.
:title A Standard Architecture for Controlling Robots
:date May 1988
:pages 25
:cost $3.25
:adnum AD-A195929
:keywords robotics architectures, hardware systems for control,
software systems for control, computational architecture
:abstract
This paper describes an architecture built to control the Utah-MIT
dextrous hand and other complex robots. These robots are
characterized by large numbers of actuators and sensors, and require
high servo rates. Consequently, powerful and flexible computer
architectures are needed to control them. The architecture described
in this paper derives its power from the highly efficient real-time
environment provided for its control processors, coupled with a
development host that enables flexible program development. The
software is characterized by simple design concepts and includes
utilities for real-time program development.
:aim 983
:author W. Eric L. Grimson
:asort Grimson, W.E.L.
:title On the Recognition of Curved Objects
:date July 1987
:pages 32
:cost $3.25
:adnum AD-A184441
:keywords object recognition, constrained search
:abstract Determining the identity and pose of occluded objects from
noisy data is a critical part of a system's intelligent interaction
with an unstructured environment. Previous work has shown that local
measurements of the position and surface orientation of small patches
of an object's surface may be used in a constrained search process to
solve this problem for the case of rigid polygonal objects using
two-dimensional sensory data, or rigid polyhedral objects using
three-dimensional data. This note extends the recognition system to
deal with the problem of recognizing and locating curved objects. The
extension is done in two dimensions, and applies to the recognition of
two-dimensional objects from two-dimensional data, or to the
recognition of three-dimensional objects in stable positions from
two-dimensional data.
:aim 984
:author Rodney A. Brooks, Anita M. Flynn, and Thomas Marill
:asort Brooks, R.A.; Flynn, A.M.; Marill, T.
:title Self Calibration of Motion and Stereo Vision for Mobile Robot
Navigation
:date August 1987
:pages 25
:cost $3.25
:adnum AD-A185602
:keywords mobile robot, self calibration, stereo vision, motion
vision
:abstract We report on experiments with a mobile robot using one
vision process (forward motion vision) to calibrate another (stereo
vision) without resorting to any external units of measurement. Both
are calibrated to a velocity dependent coordinate system which is
natural to the task of obstacle avoidance. The foundations of these
algorithms, in a world of perfect measurement, are quite elementary.
The contribution of this work is to make them noise tolerant while
remaining simple computationally. Both the algorithms and the
calibration procedure are easy to implement and have shallow
computational depth, making them (1) run at reasonable speed on
moderate uni-processors, (2) appear practical to run continuously,
maintaining an up-to-the-second calibration on a mobile robot, and (3)
appear to be good candidates for massively parallel implementations.
:aim 985
:author W. Eric L. Grimson
:asort Grimson, W.E.L.
:title On the Recognition of Parameterized Objects
:date October 1987
:pages 26
:cost $3.25
:keywords object recognition, constrained search
:abstract Determining the identity and pose of occluded objects from
noisy data is a critical step in interacting intelligently with an
unstructured environment. Previous work has shown that local
measurements of position and surface orientation may be used in a
constrained search process to solve this problem, for the case of
rigid objects, either two-dimensional or three-dimensional. This paper
considers the more general problem of recognizing and locating objects
that can vary in parameterized ways. We consider objects with
rotational, translational or scaling degrees of freedom, and objects
that undergo stretching transformations. We show that the constrained
search method can be extended to handle the recognition and
localization of such generalized classes of object families.
:aim 986
:author Harold Abelson and Gerald Jay Sussman
:asort Abelson, H.; Sussman, G.J.
:title Lisp: A Language for Stratified Design
:date August 1987
:pages 31
:cost $3.25
:adnum AD-A185606
:reference Also in {\it Byte Magazine}, February 1988.
:keywords abstraction, scheme, stratified design, Lisp
:abstract
We exhibit programs that illustrate the power of Lisp as a language
for expressing the design and organization of computational systems.
The examples are chosen to highlight the importance of {\it
abstraction} in program design and to draw attention to the use of
procedures to express abstractions.
:aim 987
:author Alan Yuille
:asort Yuille, A.L.
:title Energy Functions for Early Vision and Analog Networks
:date November 1987
:pages 53
:cost $3.75
:adnum AD-A190384
:keywords energy functions, line processors, analog networks
:abstract
This paper describes attempts to model the modules of early vision in
terms of minimizing energy functions, in particular energy functions
allowing discontinuities in the solution. It examines the success of
using Hopfield-style analog networks for solving such problems.
Finally it discusses the limitations of the energy function approach.
:aim 989
:author Alan Yuille and Shimon Ullman
:asort Yuille, A.L.; Ullman, S.
:title Rigidity and Smoothness of Motion
:date November 1987
:pages 28
:cost $3.25
:keywords aperture problems, rigidity, smoothness
:abstract
Many theories of structure from motion divide the process into two
parts which are solved using different assumptions. Smoothness of the
velocity field is often assumed to solve the motion correspondence
problem and then rigidity is used to recover the 3D structure. We
prove results showing that, in a statistical sense, smoothness of the
velocity field follows from rigidity of the motion.
:aim 994
:author Berthold K.P. Horn
:asort Horn, B.K.P.
:title Relative Orientation
:date September 1987
:pages 31
:cost $3.25
:keywords relative orientation, binocular stereo, coplanarity
condition, photogrammetry, motion vision, representation of rotation
:abstract Before corresponding points in images taken with two cameras
can be used to recover distances to objects in a scene, one has to
determine the position and orientation of one camera relative to the
other. This is the classic photogrammetric problem of {\it relative
orientation}, central to the interpretation of binocular stereo
information. Described here is a particularly simple iterative scheme
for recovering relative orientation that, unlike existing methods,
does not require a good initial guess for the baseline and the
rotation.
:aim 996
:author Rado Jasinschi and Alan Yuille
:asort Jasinschi, R.; Yuille, A.L.
:title Non-rigid Motion and Regge Calculus
:date November 1987
:pages 34
:cost $3.25
:keywords structure from motion, incremental rigidity, Regge Calculus
:abstract We study the problem of recovering the structure from
motion of figures which are allowed to perform a controlled non-rigid
motion. We use Regge Calculus to approximate a general surface by a
net of triangles. The non-rigid flexing motion we deal with
corresponds to keeping the triangles rigid and allowing bending only
at the joins between triangles. We show that depth information can be
obtained by using a modified version of the Incremental Rigidity
Scheme devised by Ullman (1984). We modify this scheme to allow for
flexing motion and call our version the Incremental Semirigidity Scheme.
:aim 997
:title Abstraction in Numerical Methods
:author Matthew Halfant and Gerald Jay Sussman
:asort Halfant, M.; Sussman, G.J.
:date October 1987
:pages 19
:cost $2.50
:reference Also in {\it Proceedings of the ACM Conference on Lisp and
Functional Programming}, 1988.
:keywords SCHEME, abstraction, programming methodology, Richardson
extrapolation, LISP
:abstract We illustrate how the liberal use of high-order procedural
abstractions and infinite streams helps us to express some of the
vocabulary and methods of numerical analysis. We develop a software
toolbox encapsulating the technique of Richardson extrapolation, and
we apply these tools to the problems of numerical integration and
differentiation. By separating the idea of Richardson extrapolation
from its use in particular circumstances we indicate how numerical
programs can be written that exhibit the structure of the ideas from
which they are formed.
:aim 998
:author Bonnie Jean Dorr
:asort Dorr, B.J.
:title UNITRAN: An Interlingual Machine Translation System
:date December 1987
:pages 13
:cost $2.50
:reference Also in {\it Proceedings of the Sixth Conference of the
American Association of Artificial Intelligence}, Seattle, WA, 1987.
:adnum AD-A193631
:keywords natural language processing, parsing, interlingual machine
translation, principles and parameters, linguistic constraints,
generation
:abstract
This report describes the UNITRAN (UNIversal TRANslator) system, an
implementation of a principle-based approach to natural language
translation. The system is ``interlingual'', {\it i.e.\/}, the model
is based on universal {\it principles\/} that hold across all
languages; the distinctions among languages are handled by settings of
{\it parameters\/} associated with the universal principles.
Interaction effects of linguistic principles are handled by the system
so that the programmer does not need to specifically spell out the
details of rule applications. Only a small set of principles covers
all languages; thus, the unmanageable grammar size of alternative
approaches is no longer a problem.
:aim 999
:author Gerald Roylance
:asort Roylance, G.
:title Expressing Mathematical Subroutines Constructively
:date November 1987
:pages 15
:cost $2.50
:adnum AD-A190559
:reference Also in {\it Proceedings of the ACM Conference on Lisp and
Functional Programming}, 1988.
:keywords mathematical subroutines
:abstract
The typical subroutines that compute $\sin(x)$ and $\exp(x)$ bear
little resemblance to our mathematical knowledge of these functions:
they are composed of concrete arithmetic expressions that include many
mysterious numerical constants. Instead of programming these
subroutines conventionally, we can express their construction using
symbolic ideas such as periodicity and Taylor series. Such an
approach has many advantages: the code is closer to the mathematical
basis of the function, less vulnerable to errors, and is trivially
adaptable to various precisions.
:aim 1004
:author Charles Rich and Richard C. Waters
:asort Rich, C.; Waters, R.C.
:title The Programmer's Apprentice Project: A Research Overview
:date November 1987
:pages 30
:cost $3.25
:keywords Programmer's Apprentice, automatic programming, clich\'es,
plans, knowledge representation, automated reasoning
:abstract
The goal of the Programmer's Apprentice project is to develop a theory
of how expert programmers analyze, synthesize, modify, explain,
specify, verify and document programs. This research goal overlaps
both artificial intelligence and software engineering. From the
viewpoint of artificial intelligence, we have chosen programming as a
domain in which to study fundamental issues of knowledge
representation and reasoning. From the viewpoint of software
engineering, we seek to automate the programming process by applying
techniques from artificial intelligence.
:aim 1005
:author Charles Rich
:asort Rich, C.
:title Inspection Methods in Programming: Clich\'es and Plans
:date December 1987
:pages 93
:cost $4.50
:adnum AD-A192782
:keywords Programmer's Apprentice, automatic programming, knowledge
representation, clich\'es, plans, engineering problem solving
:abstract Inspection methods are a kind of engineering problem solving
based on the recognition and use of standard forms or {\it clich\'es}.
Examples are given of program analysis, program synthesis and program
validation by inspection. A formalism, called the Plan Calculus, is
defined and used to represent programming clich\'es in a convenient,
canonical, and programming-language independent fashion.
:aim 1006
:author Eric W. Aboaf, Christopher G. Atkeson, David J. Reinkensmeyer
:asort Aboaf, E.W.; Atkeson, C.G.; Reinkensmeyer, D.
:title Task-Level Robot Learning: Ball Throwing
:date December 1987
:pages 18
:cost $2.50
:adnum AD-A208019
:keywords robotics, learning, tasks
:abstract
We are investigating how to program robots so that they learn tasks
from practice. One method, {\it task-level learning}, provides
advantages over simply perfecting models of the robot's lower level
systems. Task-level learning can compensate for the structural
modeling errors of the robot's lower level control systems and can
speed up the learning process by reducing the degrees of freedom of
the models to be learned. We demonstrate two general learning
procedures - fixed-model learning and refined-model learning - on a
ball-throwing robot system.
:aim 1007
:author Daphna Weinshall
:asort Weinshall, D.
:title Qualitative Depth and Shape from Stereo, in Agreement with
Psychophysical Evidence
:date December 1987
:pages 20
:cost $3.25
:adnum AD-A197259
:reference CBIP Memo No. 28
:keywords stereo vision, qualitative depth, induced-effect, motion
:abstract
Obtaining exact depth from binocular disparities is hard if camera
calibration is needed. We will show that qualitative depth
information can be obtained from stereo disparities with almost no
computations, and with no prior knowledge (or computation) of camera
parameters. We derive two expressions that order all matched points
in the images in two distinct depth-consistent ways from image
coordinates only. One is a tilt-related order $\lambda$, the other is
a depth-related order $\chi$. Using $\lambda$ demonstrates some
anomalies and unusual characteristics that have been observed in
psychophysical experiments. The same approach is applied to estimate
qualitatively changes in the curvature of a contour on the surface of
an object, with either $x$- or $y$-coordinate fixed.
:aim 1008
:author Jacob Katzenelson and Richard Zippel
:asort Katzenelson, J.; Zippel, R.
:title Software Structuring Principles for VLSI CAD
:date December 1987
:pages 17
:cost $2.50
:adnum AD-A190386
:keywords software reusability, large software system design, design
by language layers, extended C, Lisp
:abstract A frustrating aspect of the frequent changes to large VLSI
CAD systems is that so little of the old available programs can be
reused. It takes too much time and effort to find the reusable pieces
and recast them for the new use. Our thesis is that such systems can
be designed for reusability by designing the software as layers of
problem oriented languages, which are implemented by suitably
extending a ``base'' language. We illustrate this methodology with
respect to VLSI CAD programs and a particular language layer: a
language for handling networks. We present two different
implementations. The first uses UNIX and Enhanced C. The second
approach uses Common Lisp on a Lisp machine.
:aim 1011
:author Jintae Lee
:asort Lee, J.
:title Knowledge Base Integration: What Can We Learn from Database
Integration Research?
:date January 1988
:pages 33
:cost $3.25
:adnum AD-A209891
:keywords database integration, knowledge base management, distributed
databases, knowledge base integration
:abstract
This paper examines the issues and the solutions that have been
studied in database (DB) integration research and tries to draw
lessons from them for knowledge base (KB) integration.
:aim 1013
:author Neil C. Singer and Warren P. Seering
:asort Singer, N.C.; Seering, W.P.
:title Utilizing Dynamic Stability to Orient Parts
:date February 1988
:pages 15
:cost $2.50
:adnum AD-A195730
:reference See {\it Journal of Applied Mechanics}, December 1987, vol.
54, pp. 961-6.
:keywords parts feeding, orientation, robotics assembly, feeding
:abstract
The intent of this research is to study the dynamic behavior of a
solid body resting on a moving surface. Results of the study are then
used to propose methods for controlling the orientation of parts in
preparation for automatic assembly. Two dynamic models are discussed
in detail. The first examines the impacts required to cause
reorientation of a part. The second investigates the use of
oscillatory motion to selectively reorient parts. This study
demonstrates that the dynamic behaviors of solid bodies, under the
conditions mentioned above, vary considerably with small changes in
geometry or orientation.
:aim 1015
:author Bonnie Jean Dorr
:asort Dorr, B.J.
:title A Lexical Conceptual Approach to Generation for Machine
Translation
:date January 1988
:pages 22
:cost $3.25
:adnum AD-A197356
:keywords natural language processing, machine translation, generation,
thematic divergence, lexical selection, lexical conceptual structure
:abstract
This report introduces a plan for the development of a theoretically
based computational scheme of natural language generation for a
translation system. The emphasis of the project is the mapping from
the lexical conceptual structure of sentences to an underlying or
``base'' syntactic structure called {\it deep\/} structure. This
approach tackles the problems of {\it thematic\/} and {\it
structural\/} divergence, {\it i.e.\/}, it allows generation of target
language sentences that are not thematically or structurally
equivalent to their conceptually equivalent source language
counterparts. If the endeavor succeeds, knowledge-based inferencing
will not be necessary, and lexical selection and syntactic realization
will be facilitated.
:aim 1016
:author Rodney A. Brooks, Jonathan H. Connell and Peter Ning
:asort Brooks, R.A.; Connell, J.H.; Ning, P.
:title HERBERT: A Second Generation Mobile Robot
:date January 1988
:pages 11
:cost $2.50
:adnum AD-A193632
:keywords mobile robot, parallel processor, laser scanner
:abstract
In mobile robot research we believe the structure of the platform, its
capabilities, the choice of sensors, their capabilities, and the
choice of processors, both onboard and offboard, greatly constrains
the direction of research activity centered on the platform. We
examine the design and tradeoffs in a low cost mobile platform we have
built while paying careful attention to issues of sensing,
manipulation, onboard processing and debuggability of the total
system. The robot, named Herbert, is a completely autonomous mobile
robot with an onboard parallel processor and special hardware support for
the subsumption architecture [Brooks (1986)], an onboard manipulator
and a laser range scanner. All processors are simple low speed 8-bit
micro-processors. The robot is capable of real time three dimensional
vision, while simultaneously carrying out manipulator and navigation
tasks.
:aim 1017
:author Yishai A. Feldman and Charles Rich
:asort Feldman, Y.; Rich, C.
:title Pattern-Directed Invocation With Changing Equalities
:date May 1988
:pages 38
:cost $3.25
N00014-85-K-0124
:adnum AD-A198146
:keywords automated reasoning, truth maintenance, demons
:reference Submitted to the Journal of Automated Reasoning.
:abstract
The interaction of pattern-directed invocation with equality in an
automated reasoning system gives rise to a completeness problem. In
such systems, a demon needs to be invoked not only when its pattern
exactly matches a term in the reasoning data base, but also when it is
possible to create a variant that matches. An incremental algorithm
has been developed which solves this problem without generating all
possible variants of terms in the database. The algorithm is shown to
be complete for a class of demons, called {\it transparent} demons, in
which there is a well-behaved logical relationship between the pattern
and the body of the demon.
:aim 1019
:author W. Eric L. Grimson
:asort Grimson, W.E.L.
:title The Combinatorics of Object Recognition in Cluttered
Environments Using Constrained Search
:date February 1988
:pages 41
:cost $3.75
:keywords object recognition, Hough transform, combinatoric complexity
:abstract
When clustering techniques such as the Hough transform are used to
isolate likely subspaces of the search space, empirical performance in
cluttered scenes improves considerably. In this paper we establish
formal bounds on the combinatorics of this approach. Under some simple
assumptions, we show that the expected complexity of recognizing
isolated objects is quadratic in the number of model and sensory
fragments, but that the expected complexity of recognizing objects in
cluttered environments is exponential in the size of the correct
interpretation. We also provide formal bounds on the efficacy of using
the Hough transform to preselect likely subspaces, showing that the
problem remains exponential, but that in practical terms, the size of
the problem is significantly decreased.
:aim 1020
:author Richard C. Waters
:asort Waters, R.C.
:title System Validation via Constraint Modeling
:date February 1988
:pages 19
:cost $2.50
:adnum AD-A193589
:keywords constraints, validation, modeling, testing
:abstract
Constraint modeling could be a very important system validation method,
because its abilities are complementary to both testing and code
inspection. In particular, even though the ability of constraint
modeling to find errors is limited by the simplifications which are
introduced when making a constraint model, constraint modeling can
locate important classes of errors which are caused by non-local
faults (i.e., are hard to find with code inspection) and manifest
themselves as failures only in unusual situations (i.e., are hard to
find with testing).
:aim 1021
:author Pyung H. Chang
:asort Chang, P.
:title A Dexterity Measure for the Kinematic Control of Robot
Manipulator with Redundancy
:date February 1988
:pages 52
:cost $3.75
:adnum AD-A196223
:keywords redundant manipulator, dexterity measure, kinematics
:abstract
We have derived a new perforamnce measure, product of minors of the
Jacobian matrix, that tells how far kinematically redundant
manipulators are from singularity. It was demonstrated that previously
used performance measures, namely condition number and manipulability
measure allowed to change configurations, causing repeatability
problems and discontinuity effects. The new measure, on the other
hand, assures that the arm solution remains in the same
configuration, thus effectively preventing these problems.
:aim 1024
:author Christopher G. Atkeson, Eric W. Aboaf, Joseph McIntyre and
David J. Reinkensmeyer
:asort Atkeson, C.G.; Aboaf, E.W.; McIntyre, J.; Reinkensmeyer, D.
:title Model-Based Robot Learning
:date April 1988
:pages 9
:cost $2.50
:adnum AD-A208265
:abstract
Models play an important role in learning from practice. Models of a
controlled system can be used as learning operators to refine commands
on the basis of performance errors. The examples used to demonstrate
this include positioning a limb at a visual target, and following a
defined trajectory. Better models lead to faster correction of
command errors, requiring less practice to attain a given level of
performance. The benefits of accurate modeling are improved
performance in all aspects of control, while the risks of inadequate
modeling are poor learning performance, or even degradation of
performance with practice.
:aim 1025
:author Jonathan H. Connell
:asort Connell, J.H.
:title A Behavior-Based Arm Controller
:date June 1988
:pages 15
:cost $2.50
:adnum AD-A200666
Foundation
:keywords mobile robot, multiple agents, subsumption, behaviors,
control architectures
:abstract
In this paper we describe a working, implemented controller for a
real, physical mobile robot arm. The controller is composed of a
collection of 15 independent behaviors which run, in real time, on a
set of eight loosely-coupled on-board 8-bit microprocessors. We
describe how these behaviors cooperate to actually seek out and
retrieve objects using local sensory data. We also discuss the
methodology used to decompose this collection task and the types of
spatial representation and reasoning used by the system.
:aim 1026a
:author Gary L. Drescher
:asort Drescher, G.L.
:title Demystifying Quantum Mechanics - A Simple Universe with Quantum
Uncertainty
:date revised December 1988
:pages 29
:cost $3.25
:abstract An artificial universe is defined that has entirely
deterministic laws with exclusively local interactions, and that
exhibits the fundamental quantum uncertainty phenomenon: superposed
states mutually interfere, but only to the extent that no observation
distinguishes among them. Showing how such a universe could be
elucidates interpretational issues of actual quantum mechanics. The
artificial universe is a much-simplified version of Everett's
real-world model (the so-called {\it multiple-worlds} formulation). In
the artificial world, as in Everett's model, the tradeoff between
interference and observation is {\it deducible} from the universe
formalism. Artificial world examples analogous to the quantum
double-slit experiment and the EPR experiment are presented.
:aim 1027
:author Neil Singer and Warren Seering
:asort Singer, N.C.; Seering, W.P.
:title Preshaping Command Inputs to Reduce System Vibration
:date January 1988
:pages 25
:cost $3.25
:adnum AD-A208153
:keywords vibrations, oscillations, teleoperators, flexible
manipulators
:abstract
A method is presented for generating shaped command inputs which
significantly reduce or eliminate endpoint vibration. Desired system
inputs are altered so that the system completes the requested move
without residual vibration. A short move time penalty is incurred (on
the order of one period of the first mode of vibration). The
preshaping technique is robust under system parameter uncertainty and
may be applied to both open and closed loop systems. The Draper
Laboratory's Space Shuttle Remote Manipulator System simulator (DRS)
is used to evaluate the method. Results show a factor of 25 reduction
in endpoint residual vibration for typical moves of the DRS.
:aim 1028
:author Eric Saund
:asort Saund, E.
:title Symbolic Construction of a 2D Scale-Space Image
:date April 1988
:pages 59
:cost $3.75
:adnum AD-A195926
:keywords scale-space, symbolic token grouping, shape representation,
scale-space blackboard
:abstract The shapes of naturally occurring objects characteristically
involve spatial events occurring at many scales. This paper offers a
symbolic approach to constructing a primitive shape description across
scales for 2d binary (silhouette) shape images: grouping operations
are performed over collections of tokens residing on a Scale-Space
Blackboard. Two types of grouping operations are identified that,
respectively: (1) aggregate edge primitives at one scale into edge
primitives at a coarser scale, and (2) group edge primitives into
partial-region assertions, including curved-contours,
primitive-corners, and bars. This approach avoids several drawbacks
of numerical smoothing methods.
:aim 1032
:author Steven J. Gordon and Warren P. Seering
:asort Gordon, S.J.; Seering, W.P.
:title Real-Time Part Position Sensing
:date May 1988
:pages 32
:cost $3.25
:adnum AD-A203580
:keywords real-time vision, sensor based assembly, vision for
manipulation, light stripe sensor, quantization errors, sensor data
fusion
:abstract A light stripe vision system is used to measure the location
of polyhedral features of parts from a single frame of video camera
output. Issues such as accuracy in locating the line segments of
intersection in the image and combining redundant information from
multiple measurements and multiple sources are addressed. In 2.5
seconds, a prototype sensor was capable of locating a two inch cube to
an accuracy (one standard deviation) of .002 inches (.055 mm) in
translation and .1 degrees (.0015 radians) in rotation. When
integrated with a manipulator, the systems was capable of performing
high precision assembly tasks.
:aim 1037
:author Joachim Heel
:asort Heel, J.
:title Dynamical Systems and Motion Vision
:date April 1988
:pages 54
:cost $3.75
:adnum AD-A195932
:keywords dynamical systems, motion vision, Kalman filter, depth map,
motion recovery
:abstract In this paper we show how the theory of dynamical systems
can be employed to solve problems in motion vision. In particular we
develop algorithms for the recovery of dense depth maps and motion
parameters using state space observers or filters. Four different
dynamical models of the imaging situation are investigated and
corresponding filters/observers derived. The most powerful of these
algorithms recovers depth and motion of general nature using a
brightness change constraint assumption. No feature-matching
preprocessor is required.
:aim 1038
:author Ellen C. Hildreth and Shimon Ullman
:asort Hildreth, E.; Ullman, S.
:title The Computational Study of Vision
:date April 1988
:pages 50
:cost $3.75
:adnum AD-A195930