ppxscal/embedding_network huggingface dataset:
An O(n3log n) deterministic and an O(n3) Las Vegs isomorphism test for trivalent graphs
Authors: Zvi Galil, Christoph M. Hoffmann, Eugene M. Luks, Claus P. Schnorr, Andreas Weber
Venue: Journal of the ACM (JACM) (1987)

This paper describes an O(n3logn) deterministic algorithm and an O(n3) Las Vegas algorithm for testing whether two given trivalent graphs on n vertices are isomorphic. In fact, the algorithms construct the set of all isomorphisms between two such graphs, presenting, in particular, generators for the group of all automorphisms of a trivalent graph. The algorithms are based upon the original polynomial-time solution to these problems by Luks but they introduce numerous speedups. These include improved permutation-group algorithms that exploit the structure of the underlying 2-groups. A remarkable property of the Las Vegas algorithm is that it computes the set of all isomorphisms between two trivalent graphs for the cost of computing only those isomorphisms that map a specified edge to a specified edge.
Automating review of forms for international trade transactions: a natural language processing approach
Authors: V. Dhar, P. Ranganathan
Venue: ACM SIGOIS Bulletin (1986)

A major challenge in Office Automation is one of automating routine jobs that involve large-scale processing of ill-formed natural language data. Such data are often present in documents such as forms where it is necessary and/or practical to allow latitude in how the forms may be filled. In this paper, we describe a computational model designed to process free-form textual data in application forms for Letters of Credit (LC), which represent a common vehicle for initiating international trade transactions. The model is based on a variation of the case-frame or thematic-role frame instantiation methods. We describe the implementation of the model, report empirical results with real LC applications, and indicate directions we are currently pursuing to improve its performance.
Feedback vertex sets and cyclically reducible graphs
Authors: Ching-Chy Wang, Errol L. Lloyd, Mary Lou Soffa
Venue: Journal of the ACM (JACM) (1985)

The problem of finding a minimum cardinality feedback vertex set of a directed graph is considered. Of the classic NP-complete problems, this is one of the least understood. Although Karp showed the general problem to be NP-complete, a linear algorithm for its solution on reducible flow graphs was given by Shamir. The class of reducible flow graphs is the only nontrivial class of graphs for which a polynomial-time algorithm to solve this problem is known. The main result of this paper is to present a new class of graphs&mdash;the cyclically reducible graphs&mdash;for which minimum feedback vertex sets can be found in polynomial time. This class is not restricted to flow graphs, and most small graphs (10 or fewer nodes) fall into this class. The identification of this class is particularly important since there do not exist approximation algorithms for this problem having a provably good worst case performance. Along with the class and a simple polynomial-time algorithm for finding minimum feedback vertex sets of graphs in the class, several related results are presented. It is shown that there is no &ldquo;forbidden subgraph&rdquo; characterization of the class and that there is no particular inclusion relationship between this class and the reducible flow graphs. In addition, it is shown that a class of (general) graphs, which are related to the reducible flow graphs, are contained in the cyclically reducible class.
Seven plus or minus two central issues in human-computer interaction
Authors: B. Shneiderman
Venue: ACM SIGCHI Bulletin (1986)

This paper offers seven issues and specific challenges for researchers and developers of human-computer interaction. These issues are: interaction styles, input techniques, output organization, response time, error handling, individual differences, explanatory and predictive theories.
A VLSI chip for efficient transmission and retrieval of information
Authors: A. Mukherjee, M. Bassiouni
Venue: Proceedings of the 10th annual international ACM SIGIR conference on Research and development in information retrieval (1987)

In this paper, we present a functional description of a VLSI chip aimed at reducing the cost of data transmission and data access within information processing machines and distributed information systems. The chip maps standard character codes (e.g., ASCII) into more efficient codes (e.g., Huffman's codes) using a tree module of basic cells. In bit-serial communication controllers, for example, the parallel-to-serial transformation unit can be simply replaced by the proposed chip. The VLSI design can provide speeds that far exceed current and projected peak transfer rates of high-speed disks and communication controllers.
A proposed solution to the problem of levels in error-message generation
Authors: Kemal Efe
Venue: Communications of the ACM (1987)

A simple "lets talk about it" strategy is developed that enables users to explore lower level error messages through dialogue.
Using LATEX
Authors: H. Trickey
Venue: ACM SIGACT News (1988)

This note explains how to use a IATEX style that produces a good approximation to the style used in SIAM journals. The note is itself an example of the siam style in action.
A system for manipulating polynomials given by straight-line programs
Authors: T. Freeman, G. Imirzian, E. Kaltofen
Venue: Proceedings of the fifth ACM symposium on Symbolic and algebraic computation (1986)

We discuss the design, implementation, and benchmarking of a system that can manipulate symbolic expressions represented by their straight-line computations. Our system is capable of performing rational arithmetic, evaluating, differentiating, taking greatest common divisors of, and factoring polynomials in straight-line format. The straight-line results can also be converted to standard sparse format. We show by example that our system can handle problems for which conventional methods lead to excessive intermediate expression swell.
Data communication education&mdash;who needs it?
Authors: J William Riehl
Venue: ACM SIGCPR Computer Personnel (1986)

The 1980's has been described as the "age of communications." With it has come increasing recognition that modern electronic data transmission provides the critical infra-structure for all aspects of today's information-based society. While telecommunications and its component technology, data communications, has existed for over 150 years, it is in recent years that it has enjoyed explosive growth. This has been due to the confluence of powerful technical, economic and political forces, the most prominent among these being the orders of magnitude advances in information processing capacity and the continuing movement toward the deregulation of the electronic communications industry. The final court-ordered divestiture of AT T in 1984 caused further acceleration of fundamental industry changes already well underway. A measure of the degree of this change is the explosive growth experienced by the telecommunications industry as a whole, which is estimated to have doubled its total annual revenues in the period 1980 to 1885 from $60 billion to $120 billion.[2]
The development and proof of a formal specification for a multilevel secure system
Authors: Janice I. Glasgow, Glenn H. MacEwen
Venue: ACM Transactions on Computer Systems (TOCS) (1987)

This paper describes current work on the design and specification of a multilevel secure distributed system called SNet. It discusses security models in general, the various problems of information flows in SNet, and the abstract and concrete security model components for SNet. It also introduces Lucid as a language for specifying distributed systems. The model components are expressed in Lucid; these Lucid partial specifications are shown to be correct with respect to the formal model, and the two model components are shown to be consistent. The complete functional specification of SNet in Lucid, its implementation in Concurrent Euclid, and the verification of the implementation with respect to the Lucid specification are not discussed.
Trends in hardware and software usage in introductory database courses
Authors: J. K. Pierson, Jack D. Shorter
Venue: Proceedings of the eighteenth SIGCSE technical symposium on Computer science education (1987)

A survey of business schools accredited by the Assembly of American Collegiate Schools of Business has provided data on the hardware and software used in introductory database courses. Survey results show that the size computer used most often in the course is the microcomputer, followed in popularity by upper-end minicomputers. Relational database management software is used in preference over hierarchical and network DBMS.
MICROTEC mcASM, Version 1.1-Structured microcode assembler
Authors: Brad Denniston
Venue: ACM SIGMICRO Newsletter (1986)

mcASM is a second generation Structured Microcode Assembler that is a, product of a joint effort between Advanced Micro Devices and Microtec Research. Years of bit-slice and microcode assembler experience by both companies has been combined with the latest in software technology to produce this advanced implementation of a relocatable microcode assembler. New features make mcASM faster and easier to use than conventional microcode assemblers so that the assembler package does more of the detail work. This allows the programmer to concentrate on the target system algorithm thereby achieving a more intelligent and more competeitve target system sooner.
Computer graphics curricula: a survey of PhD granting departments
Authors: Bennett W. Anderson, Robert P. Burton
Venue: ACM SIGGRAPH Computer Graphics (1988)

Computer graphics is not a required course of study in the ACM computer science curriculum. Advances in computer graphics technology along with recommendations from SIGGRAPH encourage computer graphics to be required in the computer science curriculum to keep education in step. Ohlson outlines core and advanced elective computer graphics courses and suggests both be offered.A February 1987 survey of computer science PhD granting institutions shows: 1) 97 percent of the institutions already teach one or more computer graphics courses: 59 percent teach two or more courses, 2) courses cover basic and advanced material, 3) a few common textbooks determine course contents and 4) average enrollment is 29. The survey illustrates the prevalence of computer graphics courses and suggests that academic interest warrants its inclusion in future curriculum recommendations. Data from the university survey provides suggested outlines for typical computer graphics courses. Eleven of thirteen publishers answering a February 1987 survey publish or are interested in publishing computer graphics related texts.
Formal models of stepwise refinements of programs
Authors: Ali Mili, Jules Desharnais, Jean Raynomd Gagné
Venue: ACM Computing Surveys (CSUR) (1986)

Of the many ways to express program specifications, three of the most common are: as a pair of assertions, an input assertion and an output assertion; as a function mapping legal inputs to correct outputs; or as a relation containing the input/output pairs that are considered correct. The construction of programs consists of mapping a potentially complex specification into a program by recursively decomposing complex specifications into simpler ones. We show how this decomposition takes place in all three modes of specification and draw some conclusions on the nature of programming.
A survey of methods for system-level fault diagnosis
Authors: J. Xu, L. Lilien
Venue: Proceedings of the 1987 Fall Joint Computer Conference on Exploring technology: today and tomorrow (1987)

With the increasing need for efficient means of automatic fault diagnosis in large distributed computing systems, system-level fault diagnosis has been a fertile research area for the last few years. There are two types of system-level fault diagnosis methods: classical and adaptive. The classical methods select a set of tests, find results of all these tests, and then process the results to identify the faulty units. The adaptive methods first identify just one fault-free unit and then use it to identify all faulty units. Each of these types of diagnostic methods can assume so called symmetric or asymmetric test invalidation. The former states that tests performed by good units always give correct results, while tests performed by faulty units can produce any results. The latter states that a faulty unit always fails a test, even if the units that influence the test result are faulty. We survey a number of diagnosis methods for each of the two types under both invalidation assumptions. Each of the methods is considered in the context of a certain diagnostic model (such as, e.g., the Boolean n-cube model where processors are represented by nodes and links are represented by edges of a graph). Finally, a comparison of the two types of methods shows that the classical methods are faster (require fewer steps for diagnosis) but less efficient (may misdiagnose more fault-free units as faulty) than the adaptive methods.
Computational astrophysics
Authors: W. D. Arnett
Venue: Communications of the ACM (1985)

As computers become more powerful and sophisticated, computational astrophysicists will be able to find out more about stellar evolution and other astronomical phenomena.
A sound and sometimes complete query evaluation algorithm for relational databases with null values
Authors: Raymond Reiter
Venue: Journal of the ACM (JACM) (1986)

A sound and, in certain cases, complete method is described for evaluating queries in relational databases with null values where these nulls represent existing but unknown individuals. The soundness and completeness results are proved relative to a formalization of such databases as suitable theories of first-order logic. Because the algorithm conforms to the relational algebra, it may easily be incorporated into existing relational systems.
Automatic menu generation
Authors: Steve Cousins
Venue: Issue 102 (October 1987) (1987)

Conventional Prolog implementions support dynamic update of the data base using assert and retract. Changes to the data base allow global information to be shared throughout various parts of a program. The advantage is quick access to information which would otherwise be exchanged using shared Prolog variables.
Efficient synchronization of multiprocessors with shared memory
Authors: Clyde P. Kruskal, Larry Rudolph, Marc Snir
Venue: ACM Transactions on Programming Languages and Systems (TOPLAS) (1988)

A new formalism is given for read-modify-write (RMW) synchronization operations. This formalism is used to extend the memory reference combining mechanism introduced in the NYU Ultracomputer, to arbitrary RMW operations. A formal correctness proof of this combining mechanism is given. General requirements for the practicality of combining are discussed. Combining is shown to be practical for many useful memory access operations. This includes memory updates of the form mem_val := mem_val op val, where op need not be associative, and a variety of synchronization primitives. The computation involved is shown to be closely related to parallel prefix evaluation.
Legal reasoning in 3-D
Authors: M. Belzer
Venue: Proceedings of the 1st international conference on Artificial intelligence and law (1987)

This article contains a theory of normative defeasible reasoning based on the modal deontic logic 3-D. The concept of &ldquo;relative weight&rdquo; between competing norms is defined, and 3-D is used to formalize two types of legal reasoning (&ldquo;subsumptive&rdquo; and &ldquo;means/end&rdquo;). A general overview is given of a PROLOG program, 3dpr, that implements the 3-D based theory of normative reasoning.
Summation of binomial coefficients using hypergeometric functions
Authors: Michael B. Hayden, Edmund A. Lamagna
Venue: Proceedings of the fifth ACM symposium on Symbolic and algebraic computation (1986)

An algorithm which finds the definite sum of many series involving binomial coefficients is presented. The method examines the ratio of two consecutive terms of the series in an attempt to express the sum as an ordinary hypergeometric function. A closed form for the infinite sum may be found by comparing the resulting function with known summation theorems. It may also be possible to identify ranges of the summation index for which summing to a finite upper limit is the same as summing to infinity.
DFM: the data flow machine highly parallel symbol manipulation
Authors: M. Amamiya, M. Takesue, R. Hasegawa, H. Mikami
Venue: Proceedings of the 1987 Fall Joint Computer Conference on Exploring technology: today and tomorrow (1987)

The data flow architecture has good features as a basis for highly parallel symbol manipulation machine. We have proposed an architecture of list-processing-oriented data flow machine, called DFM, and built its prototype machine. This paper reports the implementation and evaluation of the DFM architecture. First, the paper clarifies the parallel and pipeline executions structure inherent in list processing, which is described by a functional language. Then, the paper offers the DFM architecture which exploits the parallelism inherent in the list processing. It is pointed out that the data flow machine is very effective for implementing the parallel and pipeline executions in list processing. The data flow machine can fully exploit the parallelism inherent in list processing, due to the ultra-multi-processing mechanism, parallel and pipeline execution mechanism based on packet communications, and nonstrict structure data manipulation mechanism which is called lenient cons mechanism.
Rapid prototyping and system development: examination of an interface toolkit for voice and telephony applications
Authors: J. T. Richards, S. J. Boies, J. D. Gould
Venue: ACM SIGCHI Bulletin (1986)

This paper discusses a set of tools supporting the rapid development of voice and telephony applications. The tools allow interfaces to be rapidly prototyped, tested and installed without impacting the underlying system. Used directly by behavioral specialists, they have played a key role in the building of two production systems. We review several essential features of this facility and then outline its role in the rapid development of a voice messaging system for the athletes and officials at the 1984 Summer Olympics in Los Angeles.
A unified approach to approximation algorithms for bottleneck problems
Authors: Dorit S. Hochbaum, David B. Shmoys
Venue: Journal of the ACM (JACM) (1986)

In this paper a powerful, and yet simple, technique for devising approximation algorithms for a wide variety of NP-complete problems in routing, location, and communication network design is investigated. Each of the algorithms presented here delivers an approximate solution guaranteed to be within a constant factor of the optimal solution. In addition, for several of these problems we can show that unless P = NP, there does not exist a polynomial-time algorithm that has a better performance guarantee.
Solving boundary-value problems with perturbations
Authors: R. E. Maeder
Venue: ACM SIGSAM Bulletin (1987)

The program Macsyma[1] is used to solve boundary- and initial-value problems for the differential equation yuml; = f(x)y. The solution is expanded into a power series and then solved by integration and equating coefficients.
Aging in the CAD business
Authors: Flo Paroli
Venue: ACM SIGDA Newsletter (1988)

Recently, GQ published a list of achievements that a 30-year-old should have reached. Of course, very few were applicable to anyone but the editors of said magazine. Here is a list of accomplishments that is more relevant to members of the DA community:
Performance evaluation of vector accesses in parallel memories using a skewed storage scheme
Authors: D. T. Harper,  III, J. R. Jump
Venue: Proceedings of the 13th annual international symposium on Computer architecture (1986)

This paper presents and evaluates a scheme for reducing the average memory access time in a vector processing architecture. This scheme uses data skewing to distribute vectors among the modules of a parallel memory system in such a way that, for typical vector access patterns, the average number of memory conflicts is reduced. It also employs both address and data buffers in each module to smooth out the transient irregularities that occur in some vector access patterns.Most previous data skewing techniques were developed to provide conflict-free access for a limited set of access strides. While the proposed scheme does not eliminate all conflicts, it improves the average performance over non-skewed parallel memories by significantly reducing the number of conflicts for a wide range of strides. Also, this effect is much less dependent on the number of memory modules than the skewing schemes used to obtain conflict-free access.
Envoys in electronic mail systems
Authors: Eric Gold
Venue: ACM SIGOIS Bulletin (1986)

Envoys are electronic mail messages that make requests at remote electronic mailers. Envoys differ from conventional messages in that they might be routed to recipients that have not been specified, their requests can often be carried out with no human intervention, they can be modified as they move from mailer to mailer, and they return to the original sender to inform her what actions have been taken. An electronic mailer that supports envoys needs reasoning systems to determine the recipients of the envoy and handle the requests.
Abstraction modual decomposition&mdash;an example
Authors: Arthur Gittleman
Venue: ACM SIGCSE Bulletin (1986)

The design and prototype implementation of an interpreter for a small BASIC-like language makes an excellent project illustrating the value of abstraction and modular decomposition. Such a project can be assigned in several different courses, either as a sequence of short assignments or as a term project.
Rule base management using meta knowledge
Authors: Mehdi T. Harandi, Thierry Schang, Seth Cohen
Venue: ACM SIGMOD Record (1986)

This paper describes the rule base management strategy of an expert system environment. The environment includes a set of integrated tools which facilitate acquisition, manipulation and maintenance of knowledge. The rule base management component of the system, called RBM, assists these tasks by organizing global semantic information within the rule base. RBM extracts this semantic information from the texts included in &ldquo;rule structures&rdquo; and builds a semantic network of the concepts found in the rule base. The rule base is then divided into rulesets which are clusters of rules that refer to the same atomic concept. Construction of this meta knowledge is achieved through a keyword matching mechanism. The paper includes a brief description of the RBM system, the dictionary it uses for building meta-level knowledge, and its keyword matching technique.
Thue systems as rewriting systems
Authors: Ronald V. Book
Venue: Journal of Symbolic Computation (1987)

This paper is a survey of recent results on Thue systems, where the systems are viewed as rewriting systems on strings over a finite alphabet. The emphasis is on Thue systems with the Church-Rosser property, where the notion of reduction is based on length-decreasing rewriting rules. The main effort is expended in outlining the properties of such systems, paying close attention to the issue of the possible decidability of properties and to the issue of the computational complexity of decidable properties. Since Thue systems may also be considered as presentations of monoids, the language of monoids (and groups) is used to describe some of these properties.