ppxscal/embedding_network huggingface dataset:
An Environment for Developing Fault-Tolerant Software
Authors: James M. Purtilo, Pankaj Jalote
Venue: IEEE Transactions on Software Engineering (1991)

An environment that supports execution of programs using both N-version programming and recovery blocks in a uniform manner is described. For N-version programming, the system offers an easy and flexible way of specifying the target machines for the separate versions. The basic unit of fault tolerance supported by this system is at the procedure or function level. Each such program unit can be packaged as its own task, and different fault tolerance techniques can subsequently be employed, even within the same application. The environment also allows versions to be written in different programming languages and executed on different machines. This enhances the independence between the different versions, making the fault tolerance techniques more effective. This environment has been developed for use on Unix-based hosts and currently runs on a network of Sun and DEC workstations.
Basic abstractions for a database programming language
Authors: P. A. Buhr, G. Ditchfield, C. R. Zarnke
Venue: Proceedings of the second international workshop on Database programming languages (1989)

Four abstractions &mdash; typing, object-based, closed systems, and reachability &mdash; are examined as to their efficacy in a database programming language. Each abstraction was chosen because of its use in a current database or persistent programming system. An attempt is made to highlight the effect of each abstraction on implementation complexity and efficiency so that designers can understand the fundamental implications of adopting one or more of these abstractions. The conclusion is that database programming languages must support some of these abstractions across the system. Other abstractions can only be implemented in a subset of the system or by user-written code because they do not scale up to a multi-user distributed persistent system.
Simplification rules and complete axiomatization for relational update transactions
Authors: Dino Karabeg, Victor Vianu
Venue: ACM Transactions on Database Systems (TODS) (1991)

Relational update transactions consisting of line programs of inserts, deletes, and modifications are studied with respect to equivalence and simplification. A sound and complete set of axioms for proving transaction equivalence is exhibited. The axioms yield a set of simplification rules that can be used to optimize efficiently a large class of transactions of practical interest. The simplification rules are particularly well suited to a dynamic environment where transactions are presented in an on-line fashion, and where the time available for optimization may consist of arbitrarily short and sparse intervals.
Intersection detection and separators for simple polygons
Authors: David M. Mount
Venue: Proceedings of the eighth annual symposium on Computational geometry (1992)

A simple algorithm is presented for detecting whether two preprocessed simple polygons intersect one another. Given a simple polygon, A, in O(n log n) time and O(n) space we preprocess A constructing an enveloping triangulation called a scaffold. To determine whether two preprocessed polygons A and B overlap another, we start with these two envelopes and successively strip away overlapping triangles of the scaffolds until we either detect an intersection between the objects or until we have succeeded in separating them spatially. The running time of the intersection query depends on the complexity of the minimum link polygonal curve separating the two objects. Given two preprocessed simple polygons A and B, placed at arbitrary locations in the plane we can determine whether these polygons intersect one another in O(m log2n is the total number of vertices and m is the complexity of a minimum link polygonal curve separating A from B. We generalize this to the problem of computing arbitrary Boolean functions of two preprocessed polygons.
Anonymous (special topic)
Authors: D. Wengelin, M. Carlsson Goethe, L. Asplund
Venue: ACM SIGAda Ada Letters (1990)

Using a source code transformation approach to Ada in a distributed environment will give some implementation difficulties. This paper presents an all Ada, portable, solution to the problem of suspending a caller on one node during a call to a remote node. The solution is based on two sets of tasks on each node, making it possible for a caller to hang on an entry during the call. Algorithms are presented in pseudo-Ada.
Towards a deductive database for small simple groups
Authors: Greg Bulter, Sridhar S. Iyer
Venue: ACM SIGSAM Bulletin (1991)

This particular study investigates the application of Prolog and the associated technology of deductive databases to the realm of modern algebra. A relatively small, yet diverse, collection of information was chosen for the feasibility study. The 56 non-abelian simple groups of order less than one million have been studied in depth. In print are several tables of information such as minimal generating pairs, presentations, character tables, and maximal subgroups. The information is very heterogeneous in nature, involving formulae, tables, lists, arbitrary precision integers, character strings, irrational numbers, and rules for deducing information from the given facts.While very much a feasibility study, the work to date demonstrates that the Prolog deductive database technology is appropriate. More primitive data types, such as irrational numbers, infinite precision numbers, and tables would improve the efficiency of Prolog in this domain. More work categorizing user queries and incorporating the necessary facts and rules to answer them is required.
Breaking the probability ½ barrier in FIN-type learning
Authors: Robert Daley, Bala Kalyanasundaram, Mahendran Velauthapillai
Venue: Proceedings of the fifth annual workshop on Computational learning theory (1992)

We show that for every probabilistic FIN-type learner with success ratio greater than 24/49, there is another probabilistic FIN-type learner with success ratio 1/2 that simulates the former. We will also show that this simulation result is tight. We obtain as a consequence of this work a characterization of FIN-type team learning with success ratio between 24/49 and 1/2. We conjecture that the learning capabilities of probabilistic FIN-type learners for probabilities beginning at probability 1/2 are delimited by the sequence 8n/17n-2 for n > 2, which has an accumulation point at 8/17.
Counterexamples to a one writer multireader atomic variable construction of Burns and Peterson
Authors: S. Halder, K. Vidyasankar
Venue: ACM SIGOPS Operating Systems Review (1992)

Two counterexamples are given to the one writer multireader multivalued atomic variable construction of Burns and Peterson [1]. The first counterexample is applicable even if the control variables in their construction are made atomic.
From LP to LP: programming with constraints
Authors: Jean-Louis Lassez
Venue: Proceedings of the third international workshop on Database programming languages : bulk types persistent data: bulk types persistent data (1992)

Constraint methods for problem solving have a long history. Recently the problem of introducing constraints as primitive constructs in programming languages has been addressed. A main task that the designers and implementers of such language face is to use and adapt the concepts and algorithms from the extensive studies on constraints done in areas such as Mathematical Programming, Symbolic Computation, Artificial Intelligence, Program Verification and Computational Geometry. Borrowing from these areas and synthesizing the various notions leads to an emerging conception of programming with constraints that we will describe here informally.
Chortle: a technology mapping program for lookup table-based field programmable gate arrays
Authors: Robert J. Francis, Jonathan Rose, Kevin Chung
Venue: Proceedings of the 27th ACM/IEEE Design Automation Conference (1991)

Field Programmable Gate Arrays are new devices that combine the versatility of a Gate Array with the user-programmability of a PAL. This paper describes an algorithm for technology mapping of combinational logic into Field Programmable Gate Arrays that use lookup table memories to realize combinational functions. It is difficult to map into lookup tables using previous techniques because a single lookup table can perform a large number of logic functions, and prior approaches require each function to be instantiated separately in a library. The new algorithm, implemented in a program called Chortle uses the fact that a K-input lookup table can implement any Boolean function of K-inputs, and so does not require a library-based approach. Chortle takes advantage of this complete functionality to evaluate all possible decompositions of the input Boolean network nodes. It can determine the optimal (in area) mapping for fanout-free trees of combinational logic. In comparisons with the MIS II technology mapper, on MCNC-89 Logic Synthesis benchmarks Chortle achieves superior results in significantly less time. 1
Timing driven placement using complete path delays
Authors: Wilm E. Donath, Reini J. Norman, Bhuwan K. Agrawal, Stephen E. Bello, Sang Yong Han, Jerome M. Kurtzberg, Paul Lowy, Roger I. McMillan
Venue: Proceedings of the 27th ACM/IEEE Design Automation Conference (1991)

The Timing Drive Placement (TDP) system balances wirability and timing constraints so that the final released design meets timing criteria. This is achieved by dynamically evaluating the timing of critical paths during placement. TDP is significant because convergence to a timed wirable solution early in the physical design cycle is achieved, or else it becomes apparent that logic changes are required.
Building an infrastructure to support writing across the computer science curriculum
Authors: David R. Falconer, Martin Katz
Venue: ACM SIGCSE Bulletin (1992)

This paper describes an infrastructure to support efforts to improve communications skills. This infrastructure is designed to support writing throughout the computer science curriculum and the typical deficiencies and attitudes of computer science faculty and majors in the area of interpersonal communications.
Residual Analysis for Feature Detection
Authors: Ming-Hua Chen, David Lee, Theo Pavlidis
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1991)

It is shown that in a very simple form residual analysis achieves results that are at least as good as if not better than those obtained by other techniques. There are many ways for extensions of the method. For example, moving average filters of regularization can be used to obtain the residual images. Also, the strength of the correlation, measured by D/sub rr/(O), can be used to eliminate noise, weak edges, etc. A more ambitious extension is by considering smoothing filters that leave invariant the function representing the reflectance from smooth surfaces.
The effects of an introductory computer course on the attitudes of older adults towards computers
Authors: J. M. Morris
Venue: Proceedings of the twenty-third SIGCSE technical symposium on Computer science education (1992)

An introductory computer course was offered to adults 60 years and older. A computer attitude survey was administered before and after the course in order to uncover preexisting concerns and reveal those attitudes most affected by the course. Attitudes following the course were marked by highly positive changes. Survey results revealed that after the course the participants felt better acquainted with computer terminology, less left out because they are unfamiliar with computers, less apprehensive about using a computer, and more certain of their ability to interpret a computer printout. An interaction diary maintained by each of the participants revealed enthusiastic learners who were eager to take more courses in the future. Contrary to widely held stereotypes, many older adults view computer technology favorably and can benefit from acquisition of basic computer skills.
Algorithm 688: EPDCOL: a more efficient PDECOL code
Authors: P. Keast, P. H. Muir
Venue: ACM Transactions on Mathematical Software (TOMS) (1991)

The software package PDECOL [7] is a popular code among scientists wishing to solve systems of nonlinear partial differential equations. The code is based on a method-of-lines approach, with collocation in the space variable to reduce the problem to a system of ordinary differential equations. There are three principal components: the basis functions employed in the collocation; the method used to solve the system of ordinary differential equations; and the linear equation solver which handles the linear algebra. This paper will concentrate on the third component, and will report on the improvement in the performance of PDECOL resulting from replacing the current linear algebra modules of the code by modules which take full advantage of the special structure of the equations which arise. Savings of over 50 percent in total execution time can be realized.
A dual-algorithm performance monitoring system (abstract)
Authors: Kevin C. Schott
Venue: Proceedings of the 1990 ACM annual conference on Cooperation (1990)

Using the compiler and interpreter published by Ben-Ari, an algorithm performance monitoring system is built. By removing the randomness from the procedure which selects and controls the execution of multiple processes an unbiased execution of two algorithms can be achieved. Creating a window mechanism for viewing simultaneous execution is accomplished by the creating extensions to the language and rewriting portions of the interpreter. The extensions indicate where performance monitoring is to begin and where it is to end as well as how the screen is to be controlled during execution. A new standard procedure is used to split the screen vertically into two windows and to set flags that control input and output to each window. Another standard procedure indicates where performance monitoring is to end and causes the screen to return to normal. All instructions encountered by the interpreter which handle the input and output have been altered. The flags cause each process's input and output requests to appear in the correct window. In an educational environment, this system can be used to illustrate the fundamental operations of an algorithm. By viewing two algorithms executing simultaneously, the student can directly compare the performance of both algorithms. The complete system was constructed using VAX Pascal and utilizes the VMS Screen Management routines to manage input and output.
Analysis of Checksums, Extended-Precision Checksums, and Cyclic Redundancy Checks
Authors: Nirmal R. Saxena, Edward J. McCluskey
Venue: IEEE Transactions on Computers (1990)

The effectiveness of extended-precision checksums is thoroughly analyzed. It is demonstrated that the extended-precision checksums most effectively exploit natural redundancy occurring in program codes. Honeywell checksums and cyclic redundancy checks are compared to extended-precision checksums. Two's complement, unsigned, and one's complement arithmetic checksums are treated in a unified manner. Results are also extended to any general radix-p arithmetic checksum. Asymptotic and closed-form formulas of aliasing probabilities for the various error models are derived.
Examples of automatic asymptotic expansions
Authors: Bruno Salvy
Venue: ACM SIGSAM Bulletin (1991)

We describe the current state of a Maple library, gdev, designed to perform asymptotic expansions for a large class of expressions. Many examples are provided, along with a short sketch of the underlying principles. At the time when this report is written, a striking feature of these examples is that none of them can be computed directly with any of today's most widespread symbolic computation systems (Macsyma, Mathematica, Maple or Scratchpad II).
The LILOG knowledge representation system
Authors: Toni Bollinger, Udo Pletat
Venue: ACM SIGART Bulletin (1991)

The LILOG knowledge representation system is part of LEU/2 - the LILOG Experimentier Umgebung1 - a natural language understanding system for German. The knowledge representation system comprises a sophisticated knowledge representation system comprises a sophisticated knowledge representation language based on order-sorted predicate logic enriched by a type system of KL-ONE like languages, default reasoning, and the capability to delegate inferences to external deductive components. The inference engine processing LLILOG can be considered as an experimental theorem proving shell since, for example, we are able to exchange inference calculi and search strategies very easily. We sketch the knowledge representation language LLILOG, give an overview of the internal architecture of the LILOG inference engine, and show how the inference engine is embedded into the natural language understanding system LEU/2.
On-Line CORDIC Algorithms
Authors: H. X. Lin, H. J. Sips
Venue: IEEE Transactions on Computers (1990)

A number of new algorithms to make an online CORDIC implementation are introduced. The online CORDIC algorithm takes n+6 clock cycles to compute a CORDIC function. It is estimated that an implementation of the proposed algorithm is six to seven times as fast as the traditional CORDIC approach for Given's rotation, and seven to eight times as fast for SVD computation.
Projective ML
Authors: Didier Rémy
Venue: Proceedings of the 1992 ACM conference on LISP and functional programming (1992)

We propose a projective lambda calculus as the basis for operations on records. Projections operate on elevations, that is, records with defaults. This calculus extends lambda calculus while keeping its essential properties. We build projective ML from this calculus by adding the ML Let typing rule to the simply typed projective calculus. We show that projective ML possesses the subject reduction property, which means that well-typed programs can be reduced safely. Elevations are practical data structures that can be compiled efficiently. Moreover, standard records are difinable in terms of projections.
Some notes about research and development at KTH
Authors: Rolf Carlson
Venue: Proceedings of the workshop on Speech and Natural Language (1991)

The Department of Speech Communication and Music Acoustics of The Royal Institute of Technology is a three-professor department with chairs in: Speech Communication, Music Acoustics, and Hearing Technology. The activities within the department are multi-disciplinary with a concentration on research.
N-factorial computations, timing, etc.
Authors: William H. Huber
Venue: ACM SIGSMALL/PC Notes (1992)

Dexter Schnebly's article in Volume 17, Number 1 (Spring 1991) raises some interesting questions regarding the timing of a program to compute the base-10 representations of factorials of small integers 3 lt;= N lt;= 21000. I wrote a short program to investigate.
IDRP protocol analysis: storage complexity
Authors: Yakov Rekhter
Venue: ACM SIGCOMM Computer Communication Review (1992)

IDRP is an inter-domain routing protocol that is based on the path-vector routing algorithm. This paper analysis storage complexity of the protocol and suggests possible local techniques for reducing it.
Structured programming in Macintosh assembly language (abstract)
Authors: Clint Foulk
Venue: Proceedings of the 1990 ACM annual conference on Cooperation (1990)

Ever since Dijkstra first pointed out the harmfulness of the Goto twenty years ago, programmers in high-level language have become more and more accustomed to writing structured programs. No such development has taken place in assembly language due to the lack of such constructs as the If-Then, If-Then-Else, While-Do, and Repeat-Until statements of Pascal. It is possible, however, to achieve the same effect by the exercise of programming discipline if all branching in the program is made to follow the rules of structured programming. For example, an If-Then statement such as If X = 0 Then Y := 1 Else Y := 2 EndIf may be implemented in Macintosh assembly language as If1 Tst.W X(A5) ;if X < > 0; Then Goto; Else1 Bne Else1 Move.W #1,Y(A5) ;Y := 1 Bra EndIf1 ;Goto Endif1 Else1 Move.W #2,Y(A5) ;Y :=2 EndIf1 While such programs may appear somewhat strange at first, consistent application of the discipline makes it very easy to convert any algorithm expressed as a structured high-level language program to Macintosh assembly language completely mechanically and, therefore, correctly. A textbook on Macintosh assembly language incorporating these principles is under development by the author.
Signal-to-String Conversion Based on High Likelihood Regions Using Embedded Dynamic Programming
Authors: Yifan Gong, Jean-Paul Haton
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1991)

A method of signal-to-string conversion based on embedded dynamic programming (DP) which can adapt its search to the variation of the input signal is proposed. The optimizing process is guided by high-valued portions of the likelihood function of symbols composing the string and is solved by two embedded dynamic programming processes. Algorithms in a Pascal-like language relating to the solution are given. When applied to continuous speech recognition on a 100-word vocabulary using the phoneme as the basic recognition unit, the method is shown to achieve a 4% improvement in the recognition rate compared to a classical DP-based method.
A Fast Recognition-Complete Processor Allocation Strategy for Hypercube Computers
Authors: Po-Jen Chuang, Nian-Feng Tzeng
Venue: IEEE Transactions on Computers (1992)

Fully recognizing various subcubes in a hypercube computer efficiently is addressed. A method with much less complexity than the multiple-GC strategy in generating the search space, while achieving complete subcube recognition, is proposed. This method is referred to as a dynamic processor allocation scheme because the search space generated is dependent on the dimension of the requested subcube dynamically. The basic idea lies in collapsing the binary tree representations of a hypercube successively so that the nodes which form a subcube but are distant are brought close to each other for recognition. The strategy can be implemented efficiently by using right rotating operations on the notations of the sets of subcubes corresponding to the nodes at a certain level of binary tree representations. Results of extensive simulation runs carried out to collect performance measures for different allocation strategies are discussed. It is shown that this strategy compares favorably in most situations with other known allocation schemes capable of achieving complete subcube recognition.
Evocative agents and multi-media interface design
Authors: Beth Adelson
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems (1992)

This paper describes research which focusses on the issue of possible roles for computerized agents within multimedia educational software.
Cooperation of the pattern recognition techniques of Dirichlet tessellations with political science to produce ward partitioning of cities without bias (abstract)
Authors: Joseph S. Szakas, Christian I. Trefftz
Venue: Proceedings of the 1990 ACM annual conference on Cooperation (1990)

For large cities with diversified citizens, representation of these people is done through the Ward Systems, as sections of a city are partitioned into smaller areas where it is easier for people to have their voices heard. The means of this partitioning is done, in many cases, to benefit the people in power rather than to optimize the true representation of the people. By utilizing the Pattern Recognition technique of Dirichlet Tesselations an attempt is made to provide a discussion of: 1) A more structured, possibly more efficient way of determining Wards without bias and 2) The problems that lie ahead in this quest to optimize citizen representation.