ppxscal/embedding_network huggingface dataset:
Case diagrams: a first step to diagrammed management information bases
Authors: Jeffrey D. Case, Craig Partridge
Venue: ACM SIGCOMM Computer Communication Review (1989)

A method for pictorially representing objects in a Management Information Base (MIB) used for network management is presented. Although the method presented here is limited in the kinds of information it can display, the authors believe that some method for diagramming MIBs like the one described here will be needed in the future.
The Problem of Expensive Chunks and its Solution by Restricting Expressiveness
Authors: Milind Tambe, Allen Newell, Paul S. Rosenbloom
Venue: Machine Learning (1990)

Soar is an architecture for a system that is intended to be capable of general intelligence. Chunking, a simple experience-based learning mechanism, is Soar's only learning mechanism. Chunking creates new items of information, called chunks, based on the results of problem-solving and stores them in the knowledge base. These chunks are accessed and used in appropriate later situations to avoid the problem-solving required to determine them. It is already well-established that chunking improves performance in Soar when viewed in terms of the subproblems required and the number of steps within a subproblem. However, despite the reduction in number of steps, sometimes there may be a severe degradation in the total run time. This problem arises due to expensive chunks, i.e., chunks that require a large amount of effort in accessing them from the knowledge base. They pose a major problem for Soar, since in their presence, no guarantees can be given about Soar's performance.In this article, we establish that expensive chunks exist and analyze their causes. We use this analysis to propose a solution for expensive chunks. The solution is based on the notion of restricting the expressiveness of the representational language to guarantee that the chunks formed will require only a limited amount of accessing effort. We analyze the tradeoffs involved in restricting expressiveness and present some empirical evidence to support our analysis.
Artifact as theory-nexus: hermeneutics meets theory-based design
Authors: J. M. Carroll, W. A. Kellogg
Venue: ACM SIGCHI Bulletin (1989)

We suggest that HCI designs characteristically embody multiple, distinct psychological claims, that virtually every aspect of a system's usability is overdetermined by independent psychological rationales inherent in its design. These myriad claims cohere in being implemented together in a running system. Thus, HCI artifacts themselves are perhaps the most effective medium for theory development in HCI. We advance a framework for articulating the psychological claims embodied by artifacts. This proposal reconciles the contrasting perspectives of theory-based design and hermeneutics, and clarifies the apparent paradox of HCI application leading HCI theory.
A parallel row-based algorithm for standard cell placement with integrated error control
Authors: J. S. Sargent, P. Banerjee
Venue: Proceedings of the 26th ACM/IEEE Design Automation Conference (1989)

A new row-based parallel algorithm for standard-cell placement targeted for execution on a hypercube multiprocessor is presented. Key features of this implementation include a dynamic simulated-annealing schedule, row-partitioning of the VLSI chip image, and two novel approaches to control error in parallel cell-placement algorithms: (1) Heuristic Cell-Coloring; (2) Adaptive Sequence Length Control.
Achievement certificates from graphics environment
Authors: T. M. Olsen
Venue: ACM SIGAPL APL Quote Quad (1987)

Karsten Manufacturing Corporation issues a &ldquo;Certificate of Hole in One&rdquo; (CHIO) to golfers who ace with PING (trademark) equipment. Formerly done manually, the certificate is now plotted automatically in less than two minutes, unattended, with two-color English Gothic and simplex italic Roman fonts, and a digitized signature, on gilded, preprinted, parchment forms. The plot file is produced from international input data received orally by telephone, or on tape from the &ldquo;Golf Digest&rdquo; clearing house. The APL2 application was implemented as an extension of the IBM GIAM graphics language and employs several new commands for loading and manipulating graphic characters from the Hershey font library. The paper explains various input panels and graphic displays. Technical obstacles including acceptable interactive and batch running-time-per-certificate are described, along with their solution. The method includes traditional MIS techniques and shows how these are applied in a production system. This is the story of how the CHIO project evolved and how we learned by doing.
Work-preserving emulations of fixed-connection networks
Authors: R. Koch, T. Leighton, B. Maggs, S. Rao
Venue: Proceedings of the twenty-first annual ACM symposium on Theory of computing (1989)

In this paper, we study the problem of emulating TG steps of an NG-node guest network on an NH-node host network. We call an emulation work-preserving if the time required by the host, TH, is &Ogr;(TGNG/NH) because then both the guest and host networks perform the same total work, &THgr;(TGNG), to within a constant factor. We say that an emulation is real-time if TH = &Ogr;(TG), because then the host emulates the guest with constant delay. Although many isolated emulation results have been proved for specific networks in the past, and measures such as dilation and congestion were known to be important, the field has lacked a model within which general results and meaningful lower bounds can be proved. We attempt to provide such a model, along with corresponding general techniques and specific results in this paper. Some of the more interesting and diverse consequences of this work include: a proof that a linear array can emulate a (much larger) butterfly in a work-preserving fashion, but that a butterfly cannot emulate an expander (of any size) in a work-preserving fashion. a proof that a mesh can be emulated in real time in a work-preserving fashion on a butterfly, even though any &Ogr;(1)-to-1 embedding of a mesh in a butterfly has dilation &OHgr;(log N), a proof that an N log N-node butterfly can be emulated in a work-preserving fashion on an N-node shuffle-exchange graph, and vice-versa, simple &Ogr;(N2/log2 N)-area and &Ogr;(N3/2/log3/2 N)-volume layouts for the N-node shuffle-exchange graph, and an algorithm for sorting N-numbers in &Ogr;(log N) steps with high probability on an N-node shuffle-exchange graph with constant size queues.
Survey of software tools for evaluating reliability, availability, and serviceability
Authors: Allen M. Johnson,  Jr., Miroslaw Malek
Venue: ACM Computing Surveys (CSUR) (1988)

In computer design, it is essential to know the effectiveness of different design options in improving performance and dependability. Various software tools have been created to evaluate these parameters, applying both analytic and simulation techniques, and this paper reviews those related primarily to reliability, availability, and serviceability. The purpose, type of models used, type of systems modeled, inputs, and outputs are given for each package. Examples of some of the key modeling elements such as Markov chains, fault trees, and Petri nets are discussed. The information is compiled to facilitate recognition of similarities and differences between various models and tools and can be used to aid in selecting models and tools for a particular application or designing tools for future needs. Tools included in the evaluation are CARE-III, ARIES-82, SAVE, MARKl, HARP, SHARPE, GRAMP, SURF, SURE, ASSIST, METASAN, METFAC, ARM, and SUPER. Modeling tools, such as REL70, RELCOMP, CARE, CARSRA, and CAST, that were forerunners to some of the current tools are noted for their contributions. Modeling elements that have gained widespread use for general systems, as well as fault-tolerant systems, are included. Tools capable of modeling both repairable and nonrepairable systems, accepting constant or time varying failure rates, and predicting reliability, availability, and serviceability parameters are surveyed.
Automatic recognition of induction variables and recurrence relations by abstract interpretation
Authors: Zahira Ammarguellat, W. L. Harrison,  III
Venue: Proceedings of the ACM SIGPLAN 1990 conference on Programming language design and implementation (1990)

The recognition of recurrence relations is important in several ways to the compilation of programs. Induction variables, the simplest form of recurrence, are pivotal in loop optimizations and dependence testing. Many recurrence relations, although expressed sequentially by the programmer, lend themselves to efficient vector or parallel computation. Despite the importance of recurrences, vectorizing and parallelizing compilers to date have recognized them only in an ad-hoc fashion. In this paper we put forth a systematic method for recognizing recurrence relations automatically. Our method has two parts. First, abstract interpretation [CC77, CC79] is used to construct a map that associates each variable assigned in a loop with a symbolic form (expression) of its value. Second, the elements of this map are matched with patterns that describe recurrence relations. The scheme is easily extensible by the addition of templates, and is able to recognize nested recurrences by the propagation of the closed forms of recurrences from inner loops. We present some applications of this method and a proof of its correctness.
Developments in Pascal-FC
Authors: G. L. Davies
Venue: ACM SIGPLAN Notices (1989)

This paper reports additions to Pascal-FC, a language designed to provide students of concurrent programming with practical experience of a variety of interprocess communication primitives. An earlier report in this journal described the facilities for using semaphores, monitors and an occam/CSP-style rendezvous. To these facilities have now been added an Ada-style rendezvous. An improved post-mortem dump has also been included.
Charles Babbage's Table of Logarithms (1827)
Authors: Martin Campbell-Kelly
Venue: IEEE Annals of the History of Computing (1988)

In 1827 Charles Babbage published his Table of Logarithms of the Natural Numbers, from 1 to 108,000. His logarithms were generally considered to be the most accurate in his day and were reprinted on numerous occasions, well into the 20th century. This paper describes Babbage's motivation for producing the tables, and the measures taken to ensure their accuracy. An assessment is given of Babbage's contribution to the art of table making.
Legal information retrieval a hybrid approach
Authors: D. E. Rose, R. K. Belew
Venue: Proceedings of the 2nd international conference on Artificial intelligence and law (1989)

SCALIR is a legal information retrieval system which uses a combination of symbolic and connectionist artificial intelligence techniques. Traditional systems used for automating legal research have many difficulties which make them &ldquo;brittle&rdquo;; SCALIR is an attempt to rectify many of these problems. SCALIR's hybrid nature is especially appropriate for the legal domain, which requires both logical and associative inferences. The system also benefits from a unique direct-manipulation style interface and the ability to improve its performance based on user feedback.
Message routing in an injured hypercube
Authors: M-S. Chen, K. G. Shin
Venue: Proceedings of the third conference on Hypercube concurrent computers and applications: Architecture, software, computer systems, and general issues - Volume 1 (1988)

A connected hypercube containing faulty components (nodes or links) is called an injured hypercube. To enable non-faulty nodes to communicate with each other in an injured hypercube, the information of component failures must be made available to those non-faulty nodes for them to route messages around the faulty components. We develop a fault-tolerant routing scheme which requires each node to know only the information on the failure of its own links. Performance of this scheme is rigorously analyzed. This scheme is not only shown to be capable of routing messages successfully in injured hypercubes when the number of component failures is less than n, but also proved to be able to choose a shortest path with a very high probability.
Taking advantage of models for legal classification
Authors: D. B. Skalak
Venue: Proceedings of the 2nd international conference on Artificial intelligence and law (1989)

Legal reasoning is often couched in terms of legal classification. We examine how three models of classification &mdash; Classical, Probabilistic and Exemplar &mdash; are used to perform legal classification. We argue that all three models of classification are implicitly applied by existing AI methods. The CABARET (&ldquo;CAse-BAsed REasoning Tool&rdquo;) system is suggested as an architecture that applies all three models. The relative difficulty of revising knowledge in rule form, in HYPO-style dimension form, and exemplar form is considered.
A binary feedback scheme for congestion avoidance in computer networks with a connectionless network layer
Authors: K. K. Ramakrishnan, Raj Jain
Venue: Symposium proceedings on Communications architectures and protocols (1988)

We propose a scheme for congestion avoidance in networks using a connectionless protocol at the network layer. The scheme uses feedback from the network to the users of the network. The interesting challenge for the scheme is to use a minimal amount of feedback (one bit in each packet) from the network to adjust the amount of traffic allowed into the network. The servers in the network detect congestion and set a congestion indication bit on packets flowing in the forward direction. The congestion indication is communicated back to the users through the transport level acknowledgement. The scheme is distributed, adapts to the dynamic state of the networks, converges to the optimal operating point, is quite simple to implement, and has low overhead while operational. The scheme also addresses a very important aspect of fairness in the service provided to the various sources utilizing the network. The scheme attempts to maintain fairness in service provided to multiple sources. This paper presents the scheme and the analysis that went into the choice of the various decision mechanisms. We also address the performance of the scheme under transient changes in the network and for pathological conditions.
Computers and elections
Authors: K. A. Frenkel
Venue: Communications of the ACM (1988)

Along the twists and turns of this year's presidential campaign trails, computers act as strategic tools that exert a decisive impact on capturing voters' attention. But a National Bureau of Standards study claims that system implementations are dangerously inadequate at the finish line, where carefully gleaned votes are less carefully counted.
Finding boundaries of the domain of definition for functions along a one-dimensional ray
Authors: Orit Shacham, Mordechai Schacham
Venue: ACM Transactions on Mathematical Software (TOMS) (1990)

A program for finding boundaries of function domains along a one-dimensional ray has been developed. The program decomposes the function into subexpressions which are recursively tested for intervals where they are undefined, negative, or fractional, or points where they equal zero. The intervals in which the subexpressions are undefined are then united to create the boundaries of the domain of definition of the whole function. The advantages of the use of such a program in solution of systems of nonlinear algebraic equations and nonlinear optimization are demonstrated.
Performance of the Direct Binary n-Cube Network for Multiprocessors
Authors: Seth Abraham, Krishnan Padmanabhan
Venue: IEEE Transactions on Computers (1989)

A mathematical model for predicting the performance of the direct binary n-cube interconnection scheme is presented. These predictions are checked against simulations of a comparable system. The results for the network are compared to known results for indirect interconnection schemes like the crossbar and indirect n-cube networks. Special operation conditions such as broadcasts and hot spots are considered. The following main inferences can be drawn from the study. Indirect networks need to use switches of size significantly larger than 2*2 to equal or better the performance of the hypercube system, under equiprobable distribution of message destinations. Sources attached to nodes in the direct network must be capable of generating multiple messages in a cycle to exploit the available bandwidth fully which is a key difference from the indirect networks. A variant of the standard broadcast algorithm introduced achieves a balanced distribution of network traffic, permitting the hypercube to support significant amounts of broadcast messages. These studies indicate that the transient effects of potential hot spot nodes on the background messages are small in the case of the hypercube.
Arrays of objects in rationalized APL
Authors: Andreas Werder
Venue: Proceedings of the international conference on APL (1987)

A number of proposals have been made so far to extend the array concept of APL to functions thus allowing functions of non-zero array rank [Bernecky 84, Brown 84]. Some of them required significant extensions to the APL language, both in syntax and in functionality. In this paper a scheme is presented which extends arrays to all classes of APL objects: data, function and operator. It is based on the extensions made by K.E. Iverson, first published in &ldquo;Rationalized APL&rdquo; [Iverson 83] and formally described in &ldquo;A Dictionary of APL&rdquo; [Iverson 87]. It is shown that the construction of arrays of any class can be achieved without additional extensions to the rationalized APL syntax. True generalized arrays, which may contain enclosed elements of any class, are introduced. A function application operator is proposed which extends the domain of a number of functions to function arrays. Finally the operator is used to rationalize vector and canonical representation of simple, derived and defined functions and function arrays.
Random number generators: good ones are hard to find
Authors: S. K. Park, K. W. Miller
Venue: Communications of the ACM (1988)

Practical and theoretical issues are presented concerning the design, implementation, and use of a good, minimal standard random number generator that will port to virtually all systems.
IRSIM: an incremental MOS switch-level simulator
Authors: A. Salz, M. Horowitz
Venue: Proceedings of the 26th ACM/IEEE Design Automation Conference (1989)

This paper describes IRSIM, an incremental switch-level simulator for MOS transistor circuits. In IRSIM, the circuit under simulation can be modified and then incrementally resimulated. This allows error correction and circuit operation verification to be performed in time proportional to the size of the modifications rather than the size of the entire circuit. To accomplish this incremental simulation, IRSIM maintains a history of circuit activity during simulation and only resimulates the sections of the circuit that deviate from their history. The program was tested on several corrections to errors that actually occurred in the design of a VLSI microprocessor. These errors were corrected and the circuit was incrementally resimulated 1.6 to 3500 times faster than simulating the entire circuit.
Enhancing XEDIT as a an APL editor
Authors: R. Swain
Venue: ACM SIGAPL APL Quote Quad (1989)

While APL2 provides a built-in editor, under VM it also offers a convenient interface to XEDIT, the VM system editor. XEDIT is an incredibly powerful general-purpose editor, well worth mastering for its many uses outside the APL environment. But it is missing some facilities specifically tailored for APL function editing. This paper describes a solution to one specific deficiency: the lack of a "name" or "whole word" change command. The XEDIT macro presented here, CN (for "change name"), corrects the problem and also offers an introduction to REXX, IBM's SAA command language, in a context familiar to APL'ers.
Concurrent programming in Smalltalk-80
Authors: R. Steigerwald, M. Nelson
Venue: ACM SIGPLAN Notices (1990)

Smalltalk-80 provides only a minimal set of concurrency control mechanisms. The fork and newProcess messages can be used to indicate that two (or more) processes can run concurrently, and a Semaphore class is provided which can be used to achieve synchronization.These features are not enough, however, to simulate true concurrency. A process will not yield the processor until it can no longer continue. This makes it all too easy to unintentionally produce code which is dependent upon yielding the processor at some specific point.The Delay and Random classes were used to force processes to yield nondeterministically. This allowed a single processor, context switching environment to be simulated. The producer/consumer problem was used to exercise the concurrent mechanisms in this investigation.
Defending against viruses and worms
Authors: S. A. Kurzban
Venue: ACM SIGUCCS Newsletter (1989)

"Computer viruses" have received a lot of attention. In fact, the best-known "viruses" have not been viruses at all, but "worms," programs that spread through networks instead of modifying programs. Both viruses and worms reproduce themselves and defensive measures have focused on stopping or slowing their spread. But that is only one type of defense. Preventing or limiting the effect of the harm that their components can cause is another. Still other measures are specific to known viruses. Ultimately, though, there is no defense better than a comprehensive security strategy that embraces user education, crisis-response teams, and technologically sound security measures including, but not limited to, those that relate specifically to the threats posed by viruses and worms.
Planning student laboratories&mdash;what isn't new?
Authors: Lisa Covi
Venue: Proceedings of the 16th annual ACM SIGUCCS Conference on User Services (1988)

Planning a computer lab is a complex project on any campus. Most planners start from scratch because either they aren't aware that others have done it already, they believe that their situation is unique or they just don't have time to investigate efforts elsewhere. Even when planning a second lab, technical, political and environmental constraints change so much that the methods used for the first lab do not apply to the second. Columbia University Center for Computing Activities (CUCCA) is in the process of planning its second computer lab. The lessons we learned in designing and operating our first lab did not necessarily help us in the second. However, in searching for issues that are common to planning any computer lab, we have found ways to plan for the unexpected: changing technology, new faculty requests, even a change in location. Instead of basing our planning on new considerations that differed from our first lab, we ended up defining issues that are common to any lab and creating a framework to accommodate the myriad of changing constraints that make every lab unique. Our framework has helped us answer some of the questions that many lab planners face. In designing the space, what layout will make it usable for both a classroom and a laboratory? In the budgeting process, how do the capital costs of installing a lab affect the continuing costs of operating it? What are the operational problems in a large lab? For upgrading facilities and growth, how does the choice of hardware and software fit into the plans for future services? How can the work be scheduled to least interfere with the present level of services? Although planning is still a complex process, the guidelines presented in this paper will provide useful information for lab planners at every level. In fact at Columbia, where microcomputing has spurred the development of departmental labs, lab planning referrals have become one of the services provided by our group. Once the issues are outlined and the possibilities are presented, informed choices can be made to create a facility to meet the needs for the chosen user population.