ppxscal/embedding_network huggingface dataset:
SLUG: A Connectionist Architecture for Inferring the Structure of Finite-State Environments
Authors: Michael C. Mozer, Jonathan Bachrach
Venue: Machine Learning (1991)

Consider a robot wandering around an unfamiliar environment, performing actions and sensing the resulting environmental states. The robot's task is to construct an internal model of its environment, a model that will allow it to predict the consequences of its actions and to determine what sequences of actions to take to reach particular goal states. Rivest and Schapire (1987a, 1987b&semi; Schapire, 1988) have studied this problem and have designed a symbolic algorithm to strategically explore and infer the structure of &ldquo;finite state&rdquo; environments. The heart of this algorithm is a clever representation of the environment called an update graph. We have developed a connectionist implementation of the update graph using a highly-specialized network architecture. With back propagation learning and a trivial exploration strategy&mdash;choosing random actions&mdash;the network can outperform the Rivest and Schapire algorithm on simple problems. Perhaps the most interesting consequence of the connectionist approach is that, by relaxing the constraints imposed by a symbolic description, it suggests a more general representation of the update graph, thus allowing for greater flexibility in expressing potential solutions.
An improved conditional branching scheme for a single instruction computer architecture
Authors: P. A. Laplante
Venue: ACM SIGARCH Computer Architecture News (1991)

A conditional branching scheme for the single instruction computer described in [3] is described. The new scheme is more practical than the one previously given.
Letter Recognition Using Holland-Style Adaptive Classifiers
Authors: Peter W. Frey, David J. Slate
Venue: Machine Learning (1991)

Machine rule induction was examined on a difficult categorization problem by applying a Holland-style classifier system to a complex letter recognition task. A set of 20,000 unique letter images was generated by randomly distorting pixel images of the 26 uppercase letters from 20 different commercial fonts. The parent fonts represented a full range of character types including script, italic, serif, and Gothic. The features of each of the 20,000 characters were summarized in terms of 16 primitive numerical attributes. Our research focused on machine induction techniques for generating IF-THEN classifiers in which the IF part was a list of values for each of the 16 attributes and the THEN part was the correct category, i.e., one of the 26 letters of the alphabet. We examined the effects of different procedures for encoding attributes, deriving new rules, and apportioning credit among the rules. Binary and Gray-code attribute encodings that required exact matches for rule activation were compared with integer representations that employed fuzzy matching for rule activation. Random and genetic methods for rule creation were compared with instance-based generalization. The strength/specificity method for credit apportionment was compared with a procedure we call &ldquo;accuracy/utility.&ldquo;
Rational Geometry in Space
Authors: Graziano Gentili, Michael A. O'Connor
Venue: Journal of Symbolic Computation (1991)

The objects and motions of geometrical modelling, graphics and robotics are most often described by rational (or close to rational) data in R^3. This leads naturally to a notion of rational geometry (as opposed to the classical notion of Euclidean geometry) where two objects are considered equal if there exists a rational rigid motion from one to the other. We show here that although the notion of equality in rational geometry differs from that of Euclidean geometry for lines and planes, the two notions coincide on collections of line segments, in particular for polyhedra. Next, by an explicit symbolic calculation and the use of a simple technique of classical number theory, we obtain a rational parameterization of the subgroup of all rational linear movements of the space which keep a given point fixed. Finally we study the equivalence relation of Q-equality among segments in the space Q^3, and give a representation of the space of equivalence classes, i.e. of the quotient space Q^3/O(3, Q).
On Evaluating the Cumulative Performance Distribution of Fault-Tolerant Computer Systems
Authors: Lorenzo Donatiello, Vincenzo Grassi
Venue: IEEE Transactions on Computers (1991)

Fault-tolerant computer systems may be evaluated by calculating their cumulative performance (e.g., number of processes jobs) over a finite mission time. A method for calculating the cumulative performance distribution assuming that the system fault-repair behavior can be modeled by a homogeneous Markov process is described. The method proposed for calculating the probability distribution of the accumulated reward over a finite mission is applicable to models of repairable and nonrepairable systems. The related solution algorithm shows a low polynomial computational complexity. The mathematical model is introduced, and the results already presented in the literature are surveyed. A comprehensive analysis of the time and space complexity of the proposed solution algorithm is presented. A numerical example is given.
Exvis: the exploratory visualization tool (abstract)
Authors: Shuhua Shen, Georges Grinstein, Stuart Smith
Venue: Proceedings of the 1990 ACM annual conference on Cooperation (1990)

An exploratory visualization (Exvis) tool has been developed by a research team at the University of Lowell's Computer Graphics Laboratory. The Exvis tool provides the representation of very high-dimensional data and supports direct interaction between the user and the data. The Exvis tool uses icons to represent the data in both visual and auditory domains. Each data record is represented by a visual icon and an auditory icon. A visual icon is a five-limb stick figure. The angles of the 5 limbs are controlled by the data values of the record. An auditory icon is a synthesized musical instrument. The data values can be mapped to the pitch, attack rate, decay rate, volume, and depth of frequency modulation of the synthesized instrument. The visual texture, produced by packing visual icons densely into a 2D display, stimulates spontaneous perceptions of structures in the data. The auditory texture, as well, can be explored by sweeping the cursor across the screen. The user can map the data to visual icon attributers and auditory icon attributes redundantly to reinforce visual perception. Alternatively, the user can map orthogonally to increase the number of data dimensions. The Exvis tool is implemented in C and the OSF/Motif widget set using X Windows, X11R4. The user can select a database from the preprocessed repertoire. There are twelve different visual icon members of the five-limb stick figure icon family that the user can select from. Fifteen predefined auditory icons and a &ldquo;create-your-own&rdquo; auditory icon are provided. The built-in sound synthesizer in the &ldquo;create-your-own&rdquo; auditory icon allows the user to create a new instrument. The selections of the parameters and the icon attribute mappings are controlled by the user. Application databases currently running on the system include MRI (Magnetic Resonance Image) data, multispectral satellite imagery data, and solutions to partial differential equation representing the field flow and reaction kinetics of a plasma inside a chemical reactor. We are continually upgrading the Exvis tool to provide a richer environment. More visual icon attributes will be supported, such as color, thickness, length and vibration rate. More visual icon families including 3D icons are being developed. A stereo phonic MIDI (Musical Instrument Digital Interface) interface is near completion.
Unification based FP interpreters
Authors: Chris Fickert, Thomas Sudkamp
Venue: ACM SIGPLAN Notices (1992)

A specification is given for the functional programming language FP using an attribute grammar formalism that defines a message passing protocol. Derivations in the grammar specify the complete evaluation of an FP program. The message passing provides a functional type checking capability. To avoid the overhead associated with message passing, the grammar is designed so that each FP primitive function and functional form receives and transmits a single message during the compilation. The language specification provides the framework for the construction of two FP interpreters.An interpreter using an innermost first evaluation strategy, the standard evaluation approach for functional composition, is implemented in Prolog. The rules of the language specification are directly translated into Prolog grammar rules. The message passing and type checking are achieved using the unification of variables in the Prolog grammar rules.The innermost first strategy requires the compilation and evaluation of the subfunctions and functional forms that comprise an FP function. A second interpreter, using the parallel logic programming language PARLOG, was constructed to incorporate eager evaluation into the analysis of an FP function. Eager evaluation is accomplished by transmitting partial results (incompletely constructed lists) throughout the evaluation structure. Whenever the partial results contain sufficient information to determine a value, these are used as input to the subfunctions that comprise the FP function being evaluated. Adding eager evaluation alters the degree of error preservation and requires a modification of the definition of FP.
A portable generic elementary function package in Ada and an accurate test suite
Authors: Ping Tak Peter Tang
Venue: ACM SIGAda Ada Letters (1991)

A comprehensive set of elementary functions has been implemented portably in Ada. The high accuracy of the implementation has been confirmed by rigorous analysis. Moreover, we present new test methods that are efficient and offer a high resolution of 0.005 unit in the last place. These test methods have been implemented portably here and confirm the accuracy of our implemented functions. Reports on the accuracy of other function libraries obtained by our test programs are also presented.
The complexity of multiway cuts (extended abstract)
Authors: E. Dahlhaus, D. S. Johnson, C. H. Papadimitriou, P. D. Seymour, M. Yannakakis
Venue: Proceedings of the twenty-fourth annual ACM symposium on Theory of computing (1992)

In the Multiway Cut problem we are given an edge-weighted graph and a subset of the vertices called terminals, and asked for a minimum weight set of edges that separates each terminal from all the others. When the number k of terminals is two, this is simply the min-cut, max-flow problem, and can be solved in polynomial time. We show that the problem becomes NP-hard as soon as k = 3, but can be solved in polynomial time for planar graphs for any fixed k. The planar problem is NP-hard, however, if k is not fixed. We also describe a simple approximation algorithm for arbitrary graphs that is guaranteed to come within a factor of 2&ndash;2/k of the optimal cut weight.
A Look into the Future of Information Processing
Authors: Heinz Zemanek
Venue: IEEE Annals of the History of Computing (1990)

The computing center of the Friedrich-Alexander University, Erlangen-Nuremburg in Germany, was inaugurated on November 29, 1968, with the installation of a Control Data 3300. In this invited address given in celebration of the event at that time, the attempted to forecast the future of information processing during the 20 years to follow.
APL technology of computer simulation
Authors: A. Yu Boozin, I. G. Pospelov
Venue: ACM SIGAPL APL Quote Quad (1991)

The advantages and disadvantages of APL language usage for computer simulation are considered. The language has been actively used in the Computing Center for the last ten years for simulation of socio-economic systems. The original software package was developed with the aid of APL #9733;PLUS/PC. This package makes simulation research easy and helps to get the results in graphical form.
A faster deterministic maximum flow algorithm
Authors: V. King, S. Rao, R. Tarjan
Venue: Proceedings of the third annual ACM-SIAM symposium on Discrete algorithms (1992)

We describe a deterministic version of a 1990 Cheriyan, Hagerup, and Mehlhorn randomized algorithm for computing the maximum flow on a directed graph with n nodes and m edges which runs in time O(mn + n2+&egr;, for any constant &egr;. This improves upon Alon's 1989 bound of O(mn + n8/3log n) [A] and gives an O(mn) deterministic algorithm for all m > n1+&egr;. Thus it extends the range of m/n for which an O(mn) algorithm is known, and matches the 1988 algorithm of Goldberg and Tarjan [GT] for smaller values of m/n.
Standards-Point/Counterpoint: Safety Standards for CRT Visual Display Units
Authors: J. Robert Ashley
Venue: Computer (1992)

The alleged health hazards of prolonged exposure to computer monitors which have engendered much discussion in the industry and in legislative bodies, are discussed from two different viewpoints. Ashley states that, in terms of measured quantities and current knowledge of biological interactions, only the ELF electric fields near visual display units (VDUs) have the possibility of a significant biological effect on human tissue. Any frequency magnetic field exposure near VDUs is biologically insignificant. Buckley lists his objections to the content of Ashley's arguments.
Mechanical manipulation for a class of differential systems
Authors: Dongming Wang
Venue: Journal of Symbolic Computation (1991)

In this paper we describe a mechanical procedure for computing the Liapunov functions and Liapunov constants for a class of differential systems. These functions and constants are used for establishing the stability criteria, the conditions for the existence of a center and for the investigation of limit cycles. Some problems for handling the computed constants, which are usually large polynomials in terms of the coefficients of the differential system, and an approach towards their solution by using computer algebraic methods are proposed. This approach has been successfully applied to check some known results mechanically. The author has implemented a system DEMS on an HP1000 and in Scratchpad II on an IBM4341 for computing and manipulating the Liapunov functions and Liapunov constants. As examples, two particular cubic systems are discussed in detail. The explicit algebraic relations between the computed Liapunov constants and the conditions given by Saharnikov are established, which leads to a rediscovery of the incompleteness of his conditions. A class of cubic systems with 6-tuple focus is presented to demonstrate the feasibility of our approach for finding systems with higher multiple focus.
Parallel and Deterministic Algorithms from MRFs: Surface Reconstruction
Authors: Davi Geiger, Federico Girosi
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1991)

Deterministic approximations to Markov random field (MRF) models are derived. One of the models is shown to give in a natural way the graduated nonconvexity (GNC) algorithm proposed by A. Blake and A. Zisserman (1987). This model can be applied to smooth a field preserving its discontinuities. A class of more complex models is then proposed in order to deal with a variety of vision problems. All the theoretical results are obtained in the framework of statistical mechanics and mean field techniques. A parallel, iterative algorithm to solve the deterministic equations of the two models is presented, together with some experiments on synthetic and real images.
Decomposition of Convex Polygonal Morphological Structuring Elements into Neighborhood Subsets
Authors: Jianning Xu
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1991)

A discussion is presented of the decomposition of convex polygon-shaped structuring elements into neighborhood subsets. Such decompositions will lead to efficient implementation of corresponding morphological operations on neighborhood-processing-based parallel image computers. It is proved that all convex polygons are decomposable. Efficient decomposition algorithms are developed for different machine structures. An O(1) time algorithm, with respect to the image size, is developed for the four-neighbor-connected mesh machines; a linear time algorithm for determining the optimal decomposition is provided for the machines that can quickly perform 3*3 morphological operations.
The interface specialist: contrasting opinions on role content
Authors: Lorraine F. Normore
Venue: ACM SIGCHI Bulletin (1991)

Through involvement in on-going development projects, we investigated issues brought about by having interface specialists rather than generally trained system development staff designing and developing interfaces. This article reports on some of the issues raised, discusses the activities associated with this project and points out differences in the perceptions of the tasks seen as relevant to this role by a human factors professional and by systems development staff.
Stabilizing Communication Protocols
Authors: Mohamed G. Gouda, Nicholas J. Multari
Venue: IEEE Transactions on Computers (1991)

A communication protocol is stabilizing if and only if starting from any unsafe state (i.e. one that violates the intended invariant of the protocol), the protocol is guaranteed to converge to a safe state within a finite number of state transitions. Stabilization allows the processes in a protocol to reestablish coordination between one another whenever coordination is lost due to some failure. The authors identify some important characteristics of stabilizing protocols; they show in particular that a stabilizing protocol is nonterminating, has an infinite number of safe states, and has timeout actions. They also propose a formal method for proving protocol stabilization: in order to prove that a given protocol is stabilizing, it is sufficient (and necessary) to exhibit and verify what is called a 'convergence stair' for the protocol. Finally, they discuss how to redesign a number of well-known protocols to make them stabilizing; these include the sliding-window protocol and the two-way handshake.
A concern about the Samuelson-Glushko survey
Authors: Jef Raskin
Venue: ACM SIGCHI Bulletin (1991)

The reports by Samuelson and Glushko (1990a, 1990b) conclude that most workers in the user interface design field tend to oppose copyright and patent protection for user interfaces "because they think such protection would adversely affect the climate of open exchange and discussion of research and design innovations that has brought progress to the field." Samuelson and Glushko also state that "a fundamental purpose of the intellectual property laws is to provide protection for innovations in order to give incentives for people to be creative, thereby promoting progress in various fields of endeavor." (1990b, pg. 17) The position of the respondents to the survey with respect to this well-known fact about intellectual property law is paradoxical.
Revisions: seeing the text, again
Authors: Stephen Bernhardt
Venue: ACM SIGDOC Asterisk Journal of Computer Documentation (1992)

It is a rare pleasure in academic publishing to have a piece noticed, discussed, and in this instance reprinted. Even rarer is to have a piece written for an academic audience gather attention from people in industry. So often, writing for academic journals is like shooting fireworks. If things go well, there is a brief flash, perhaps some oohs and ahs, and then darkness.
A diagnostic view on information technology
Authors: Motamarri Saradhi
Venue: ACM SIGSOFT Software Engineering Notes (1992)

Computers, computerization, Systems Analysis, Systems Design etc., have become the catchwords of the day. In majority of the cases analysis is interpreted in the narrow sense as the study of the existing system in view of computerizing its operations. The thrust for computerization is emphasized without any relevance to the context of application.The real power of the computer, its limitations, and level of applicability are not properly thought of. Computerization at most, is one facet of Information Technology; is surprisingly overlooked. The aim of this article is to drive home the point that a much rational thought and approach are mandatory to get fruitful benefits out of Information Technology.
System construction with object-oriented pictures
Authors: George W. Cherry
Venue: ACM SIGSOFT Software Engineering Notes (1991)

This paper describes the process guide, behavior model, icons, and diagrams of SCOOP-3, a pictorial method for developing reactive systems. SCOOP-3's semantics are Concurrent C++ or Ada: its icons and diagrams are mechanically translatable to these languages. SCOOP-3's process guide supports reuse, prototyping, and concurrent specification and design. Its behavior model (S-R Machines) integrates the notions of finite and infinite automata, data abstractions, and objects. My earlier notes in SEN demonstrated the Finite State Automata power of S-R Machines. This note demonstrates their far greater power and expressiveness. SCOOP-3's black box, machine, and clear box diagrams have the same objective (and names!) as Mills' Box-Structured approach: stepwise provable specifications and designs.
Information and syntax in spoken language systems
Authors: Mark Steedman
Venue: Proceedings of the workshop on Speech and Natural Language (1989)

The present paper argues that the notion of "intonational structure" as formulated by Pierrehumbert, Selkirk, and others, can be subsumed under the generalised notion of syntactic surface structure that emerges from a theory of grammar based on a "Combinatory" extension to Categorial Grammar. According to this theory, the syntactic structures and the intonation structures of English are identical, and have the same grammar. Some simplifications appear to follow for the problem of integrating syntax and other high-level modules in spoken language systems.
Proving the correctness of storage representations
Authors: Mitchell Wand, Dino P. Oliva
Venue: Proceedings of the 1992 ACM conference on LISP and functional programming (1992)

Conventional techniques for semantics-directed compiler derivation yield abstract machines that manipulate trees. However, in order to produce a real compiler, one has to represent these trees in memory. In this paper we show how the technique of storage-layout relations can be applied to verify the correctness of storage representations in a very general way. This technique allows us to separate denotational from operational reasoning, so that each can be used when needed. As an example, we show the correctness of a stack implementation of a language including dynamic catch and throw. The representation uses static and dynamic links to thread the environment and continuation through the stack. We discuss other uses of these techniques.
Polymorphic type reconstruction for garbage collection without tags
Authors: Benjamin Goldberg, Michael Gloger
Venue: ACM SIGPLAN Lisp Pointers (1992)

Several papers, have recently claimed that garbage collection can be performed on untagged data in the presence of ML-style type polymorphism. They rely on the ability to reconstruct the type of any reachable object during garbage collection. The bad news is that this is false&mdash;there can be reachable objects in the program whose type cannot be determined by the garbage collector. The good news is that tag-free garbage collection can be performed anyway&mdash;any object whose type cannot be determined by the collector is, in fact, garbage. Such objects can be discarded by the collector. This is the key result of this paper. We present a type reconstruction algorithm that can determine the type of any non-garbage object. Unfortunately, the implementation of the tag-free collector for a polymorphically typed language is difficult in ways that were not described in the previous papers, and we address some implementation issues as well. However, we mainly describe how to perform type reconstruction during garbage collection and do not attempt to address practical issues of the garbage collection process.