ppxscal/embedding_network huggingface dataset:
Availability in the Sprite distributed file system
Authors: Mary Baker, John Ousterhout
Venue: ACM SIGOPS Operating Systems Review (1991)

In the Sprite environment, tolerating faults means recovering from them quickly. Our position is that performance and availability are the desired features of the typical locally-distributed office/engineering environment, and that very fast server recovery is the most cost-effective way of providing such availability. Mechanisms used for reliability can be inappropriate in systems with the primary goal of performance, and some availability-oriented methods using replicated hardware or processes cost too much for these systems. In contrast, availability via fast recovery need not slow down a system, and our experience in Sprite shows that in some cases the same techniques that provide high performance also provide fast recovery. In our first attempt to reduce file server recovery times to less than 90 seconds, we take advantage of the distributed state already present in our file system, and a high-performance log-structured file system currently under implementation. As a long-term goal, we hope to reduce recovery to 10 seconds or less.
ROBOTICS: a hands-on introduction to hardware (abstract)
Authors: Carl Steidley
Venue: Proceedings of the 1990 ACM annual conference on Cooperation (1990)

To provide our students with a more complete understanding of computer architecture, organization, and hardware, we in the Computer Science Department at CWU proposed an integrated approach to these topics in a grant proposal to NSF's CSIP Program. One of the aspects of this proposal was to develop a course entitled Microprocessor Systems. This course was to be supported by a laboratory built around an intentionally primitive microprocessor/computer development system which prevents extensive hardware from masking machine architecture and operation. Our overall objective for the course was to aid students in comprehending that during their careers as computer scientists they may encounter, in addition to supercomputers, mainframes, minis, and micros, the computer in a variety of engineering systems whose outputs will not always be on hardcopy, tape, disc, or CRT screen. With funds from NSF to purchase equipment for the supporting laboratory, CPSC 418 Microprocessor Systems was offered for the first time in the Spring Quarter of 1989. The central equipment purchases for this course's laboratory were eight LJ Electronics Atlas II Robotic Systems and two CES Industries 6009 Robotic Systems. While our objectives were primarily aimed at having students learn more computer architecture, organization and hardware, we also wanted them to learn some elementary robotics and general interfacing techniques. Thus, the course was offered as a four-credit, undergraduate research oriented course in which students were offered open-ended projects to complete. The course, its laboratory and equipment, student projects, and future plans for a robot programming language translator as student projects will be presented. It is planned that progress in the robot programming language translator will be presented at the 1991 ACM/CSC.
Automatic reconfiguration in Autonet
Authors: Thomas L. Rodeheffer, Michael D. Schroeder
Venue: ACM SIGOPS Operating Systems Review (1991)

Autonet is a switch-based local area network using 100 Mbit/s full-duplex point-to-point links. Crossbar switches are interconnected to other switches and to host controllers in an arbitrary pattern. Switch hardware uses the destination address in each packet to determine the proper outgoing link for the next step in the path from source to destination. Autonet automatically recalculates these forwarding paths in response to failures and additions of network components. This automatic reconfiguration allows the network to continue normal operation without need of human intervention. Reconfiguration occurs quickly enough that higher-level protocols are not disrupted. This paper describes the fault monitoring and topology acquisition mechanisms that are central to automatic reconfiguration in Autonet.
Software Effort Models for Early Estimation of Process Control Applications
Authors: Tridas Mukhopadhyay, Sunder Kekre
Venue: IEEE Transactions on Software Engineering (1992)

Models are developed to estimate lines of code and function counts directly from user application features of process control systems early in the software development lifecycle. Since the application features are known with reasonable degree of confidence during early stages of development, it is possible to extend the use of the constructive cost model (COCOMO) and function-points-based approach for early software cost estimation. Alternative feature-based models that estimate size and effort using application features and productivity factors are developed. The feature-based models have been shown to estimate software effort with the least error.
Performance evaluation of cautious waiting
Authors: Meichun Hsu, Bin Zhang
Venue: ACM Transactions on Database Systems (TODS) (1992)

We study a deadlock-free locking-based concurrency control algorithm, called cautious waiting, which allows for a limited form of waiting. The algorithm is very simple to implement. We present an analytical solution to its performance evaluation based on the mean-value approach proposed by Tay et al. [18]. From the modeling point of view, we are able to do away with a major assumption used in Tay's previous work, and therefore capture more accurately both the restart and the blocking rates in the system. We show that to solve for this model we only need to solve for the root of a polynomial. The analytical tools developed enable us to see that the cautious waiting algorithm manages to achieve a delicate balance between restart and blocking, and therefore is superior (i.e., has higher throughput to both the no-waiting (i.e., immediate restart) and the general waiting algorithms under a wide range of system parameters. The study substantiates the argument that balancing restart and blocking is important in locking systems.
Cataloguing and classification for object libraries
Authors: B. Henderson-Sellers, C. Freeman
Venue: ACM SIGSOFT Software Engineering Notes (1992)

Reusable object classes are seen as a major benefit of adopting the object-oriented paradigm in the commercial data processing and applications programming worlds. However, without some efficient and effective method of locating previously written classes, this benefit of reuse will be lost. Code location requires the classes to be stored in some retrievable fashion. Such an underlying classification system, together with an associated cataloguing system, appropriate for object libraries, is proposed.
Automatic test generation using quadratic 0-1 programming
Authors: Srimat T. Chakradhar, Vishwani D. Agrawal, Michael L. Bushnell
Venue: Proceedings of the 27th ACM/IEEE Design Automation Conference (1991)

We recently proposed an unconventional digital circuit modeling technique and formulated test generation as an energy minimization problem [7]. Although energy minimization is as hard as test generation, the new approach has two advantages. Since the circuit function is mathematically expressed, operations research techniques like linear and non-linear programming can be applied to test generation. The non-causal form of the model makes parallel processing possible. The energy function E, a quadratic 0-1 function, is split into two sub-functions, a homogeneous posiform and an inhomogeneous posiform. The minimum of E is the sum of the minima of the two sub-functions, each having a minimum value of 0. We obtain a minimizing point of the homogeneous posiform, in time complexity that is linear in the number of sub-function terms, and check if the other sub-function becomes 0. When both become 0, we have a test vector. We discuss several easily parallelizable speedup techniques using the transitive closure and other graph properties. Preliminary results on combinational circuits confirm the feasibility of this technique.
Design of an OPAC database to permit different subject searching accesses in a multi-disciplines universities library catalogue database
Authors: Maristella Agosti, Maurizio Masotti
Venue: Proceedings of the 15th annual international ACM SIGIR conference on Research and development in information retrieval (1992)

This paper presents searching approaches and user interface capabilities of DUO, an Online Public Access Catalogue (OPAC) designed to permit the users of three Universities of the Northeast of Italy different subject searching accesses to the co-operative multi-disciplines library catalogue database. The co-operative catalogue database is managed by one of the software systems developed under the italian national project for library automation: the SBN project. Since the SBN database has not been designed to be efficiently accessed for end-user searches, the DUO database has been designed to avoid duplication of the SBN database data and to be usable for making efficient subjects accesses to the catalogue documents. The DUO design choices are presented, in particular the main choice of designing a &ldquo;virtual&rdquo; document that corresponds to each SBN document and that has unstructured data usable for subject search purposes. The paper presents a new kind of user-OPAC dialogue that makes available to the user different search approaches and on-line dictionaries. In particular the user during the interaction with the search tool can represent his information needs with the support of interface capabilities that are based on retrieval path history, and words and codes on-line dictionaries. DUO is the first Italian OPAC that has been made openly available to users of universities and research institutions. For this reason, it is also the first time that OPAC log data is going to be collected in Italy. This work mainly intends to make a modern OPAC available to the users of a SBN catalogue database, but it is going to permit also to build up a knowledge on OPAC usage in Italy.
PIE: A Dynamic Failure-Based Technique
Authors: Jeffrey M. Voas
Venue: IEEE Transactions on Software Engineering (1992)

A dynamic technique called PIE (propagation, infection, and execution) is presented for statistically estimating three program characteristics that affect a program's computational behavior: (1) the probability that a particular section of a program is executed, (2) the probability that the particular section affects the data state, and (3) the probability that a data state produced by that section has an effect on program output. These three characteristics can be used to predict whether faults are likely to be uncovered by software testing.
The Beginnings of Computing Activities at the Atomic Energy Authority, 1952-1972
Authors: Albert Amouyal
Venue: IEEE Annals of the History of Computing (1990)

The French Atomic Energy Authority (Commissariat àl'Énergie Atomique or CEA) started to investigate electronic computing in 1952 and in 1956 created a specialized team, trained in England. It bought its first digital computers in 1957. From then on it continually acquired the most powerful computing equipment available (IBM Stretch, IBM 360/91, CDC 7600) to meet the needs of both civilian and military nuclear research. For many years, the CEA was IBM's largest customer outside the United States. In 1972 the Computer Division of the "Civilian CEA" was subsidiarized into a leading European software company, the CISI.
Spreadsheet computations in computer algebra
Authors: S. Kamal Abdali, Guy W. Cherry, Neil Soiffer
Venue: ACM SIGSAM Bulletin (1992)

In this paper, we analyze the concept of spreadsheet computing in computer algebra. Numerical spreadsheet programs have a unique, intuitively clear semantics. But when the variables used in a spreadsheet program are allowed to assume symbolic expressions as values, the meaning of spreadsheet computations is not defined that simply. We consider several alternative models for what spreadsheet computations could mean in the symbolic context. We describe the implementation of spreadsheet features, based on one of these models, in the visual computer algebra environment MathScribe.
Biologically based machine learning paradigms: an introductory course
Authors: Adel M. Abunawass
Venue: Proceedings of the twenty-third SIGCSE technical symposium on Computer science education (1992)

This paper describes an introductory course on biologically based sub-symbolic machine learning paradigms. Specifically, this paper covers Artificial Neural Networks, Genetic Algorithms and Genetics-Based Machine Learning. It provides the structure, motivation, content, texts and tools for the course. This course is suitable for an upper division undergraduate level course or as an introductory graduate course. The paper includes a section on bibliographical references to aid the instructor in preparing for this course.
A decision-theoretic approach to robotic control systems
Authors: Kenneth Basye
Venue: ACM SIGART Bulletin (1991)

We present an approach to building high-level control systems for robotics based on Bayesian decision theory. We show how this approach provides a natural and modular way of integrating sensing and planning. We develop a simple solution for a particular problem as an illustration. We examine the cost of using such a model and consider the areas in which abstraction can reduce this cost. We focus on one area, spatial abstraction, and discuss the design issues that arise in choosing an abstraction that we have used to solve problems involving robot navigation, and give a detailed account of the mapping from raw sensor data to the abstraction.
A service for remote computations in a distributed system (abstract)
Authors: Ljudmil Manasiev
Venue: Proceedings of the 1990 ACM annual conference on Cooperation (1990)

The paper proposes an approach to creating a remote computational service in a distributed system. The service allows a user, working in a distributed system node, to execute and manage task(s) in one or several of the remaining nodes of the system. The purpose is to maintain the local node as such and simultaneously to manage on system input/output level the tasks performed in remote nodes. The division of the stations into &ldquo;Remote Computational&rdquo; servers and workstations is relative and reflects the status at a fixed point of time. The inter-relations between the nodes can be changed dynamically. Each workstation can become server or be a workstation and server simultaneously (of course, in case of a multitasking local operating system). The remote computational service is based on the object oriented organization. This means that there exist classes of objects, whose representative at any distributed system node can make it a server, workstation or both at the same time. The classes of objects can be divided into two basic groups: server's and workstation's. The essence of the approach allows its application to heterogeneous distributed systems.
Randomized multidimensional search trees: further results in dynamic sampling (extended abstract)
Authors: Ketan Mulmuley
Venue: Proceedings of the 32nd annual symposium on Foundations of computer science (1991)

The use of randomization in dynamic search structures by means of a technique called dynamic sampling is investigated. In particular, an efficient algorithm for dynamic (logarithmic time) point location in 3-D partitions induced by a set of possibly interesting polygons in R/sup 3/ is given. The expected running time of the algorithm on a random sequence of updates is close to optimal. Efficient algorithms for dynamic nearest-k-neighbor queries and half space range queries in R/sup d/ are also given.
Multimedia Conferencing on Local Area Networks
Authors: Chiam Zeigler, Gerald Weiss
Venue: Computer (1990)

Management and implementation procedures for data delivery in multiparty, multimedia conferences on local area networks are considered. Earlier results are extended, and the requirements and mechanisms for delivering multiple information types-voice, video, file, memo, screen, and keyboard data-are outlined. The mechanisms presented are appropriate for both intranetwork and (homogeneous and heterogeneous) internetwork conferences. They are also examined for their applicability to networks with and without multicast transmission capabilities. Conference management issues are discussed, and experiences in designing and experimentally implementing voice-only and multimedia conference data-delivery schema are reviewed.
Game playing as a technique for teaching parallel computing concepts
Authors: Andrew T. Kitchen, Nan C. Schaller, Paul T. Tymann
Venue: ACM SIGCSE Bulletin (1992)

Blackboard tracing of algorithms, while an effective tool for the teaching of sequential programming, is singularly ineffective and confusing when applied to parallel computing. The use of classroom games to illustrate concepts and pathologies proves to be a useful alternative technique. Games in which students play the role of processors can be used to illustrate simple parallel algorithms as well as more complex concepts. Live demonstrations are stimulating for both the participants and the class as a whole. This paper discusses guidelines regarding the development of such exercises and presents several examples.
A Polynomial time Algorithm for the Local Testability Problem of Deterministic Finite Automata
Authors: Sam M. Kim, Robert McNaughton, Robert McCloskey
Venue: IEEE Transactions on Computers (1991)

The local testability problem of deterministic finite automata is investigated. A locally testable language is a language with the property that, for some nonnegative integer k, whether or not a word w is in the language depends on (1) the prefix and suffix of w of length k, and (2) the set of substrings of w length k+1, without regard to the order in which these substrings occur. The local testability problem is, given a deterministic finite automation, to decide whether or not it accepts a locally testable language. The authors present an O(n/sup 2/) time algorithm for the local testability problem based on two simple properties that characterize locally testable automata.
The CTalk programming language: a strategic evolution of APL
Authors: Jean-Jacques Girardot
Venue: Proceedings of the international conference on APL (1992)

This document presents CTalk, which is a new programming language quite different from APL itself. CTalk is an attempt to combine the &ldquo;best&rdquo; features of APL, but also of other languages such as Lisp [9], and offer a language that looks &ldquo;satisfactory&rdquo; according to the criteria of the mainstream of computer science. The most important features of CTalk are its syntax, which is very close to the one of the C programming language, the adoption of fundamental conceps that were missing in APL, such as lexical binding, but also the integration of a wide range of array operations that are borrowed from APL./par> It is shown here that CTalk can be implemented more simply and more efficiently than APL, while keeping all the power of APL operations, and being an acceptable alternative to APL itself.
Simple conditions for guaranteeing higher normal forms in relational databases
Authors: C. J. Date, Ronald Fagin
Venue: ACM Transactions on Database Systems (TODS) (1992)

A key is simple if it consists of a single attribute. It is shown that if a relation schema is in third normal form and every key is simple, then it is in projection-join normal form (sometimes called fifth normal form), the ultimate normal form with respect to projections and joins. Furthermore, it is shown that if a relation schema is in Boyce-Codd normal form and some key is simple, then it is in fourth normal form (but not necessarily projection-join normal form). These results give the database designer simple sufficient conditions, defined in terms of functional dependencies alone, that guarantee that the schema being designed is automatically in higher normal forms.
Mechanically Verifying Concurrent Programs with the Boyer-Moore Prove
Authors: D. M. Goldschlag
Venue: IEEE Transactions on Software Engineering (1990)

A proof system suitable for the mechanical verification of concurrent programs is described. This proof system is based on Unity, and may be used to specify and verify both safety and liveness properties. However, it is defined with respect to an operational semantics of the transition system model of concurrency. Proof rules are simply theorems of this operational semantics. This methodology makes a clear distinction between the theorems in the proof system and the logical inference rules and syntax which define the underlying logic. Since this proof system essentially encodes Unity in another sound logic, and this encoding has been mechanically verified, this encoding proves the soundness of this formalization of Unity. This proof system has been mechanically verified by the Boyer-Moore prover. This proof system has been used to mechanically verify the correctness of a distributed algorithm that computes the minimum node value in a tree.
A new min-cut placement algorithm for timing assurance layout design meeting net length constraint
Authors: Masayuki Terai, Kazuhiro Takahashi, Koji Sato
Venue: Proceedings of the 27th ACM/IEEE Design Automation Conference (1991)

This paper presents a new min-cut placement algorithm for timing assurance layout design. When critical nets are given net length constraints, the proposed algorithm can place cells so that the constraints may be met. This algorithm is built into the layout system for gate arrays called GALOP [1] and has been successfully applied to clock skew control of an ECL 12K-gate gate array.
A modular and open object-oriented database system
Authors: Satish M. Thatte
Venue: ACM SIGMOD Record (1991)

On 30 August 1990, Texas Instruments Incorporated, Dallas, TX was awarded a three year contract (Contract No. DAAB07-90-C-B920) to develop a modular and open object-oriented database system. The contract is funded by DARPA/ISTO and is being managed by the U.S. Army, CECOM, Fort Monmouth, N.J. The contract is being executed at TI's Information Technologies Laboratory, Computer Science Center, Dallas, Texas. So far, we have received an outstanding response from interested parties (database research community, OODB application developers, OODB builders) to our contract award announcement. This communication is a collection of most commonly asked questions and answers to them.
Optimization in a distributed processing environment using genetic algorithms with multivariate crossover
Authors: Aaron H. Konstam, Stephen J. Hartley, William L. Carr
Venue: Proceedings of the 1992 ACM annual conference on Communications (1992)

We set out to demonstrate the effectiveness of distributed genetic algorithms using multivariate crossover in optimizing a function of a sizable number of independent variables. Our results show that this algorithm has unique potential in optimizing such functions. The multivariate crossover meta-strategy, however, did not result in a singularly better performance of the algorithm than did simpler crossover strategies.
Dragon
Authors: Janet M. Baker, James K. Baker
Venue: Proceedings of the workshop on Speech and Natural Language (1989)

Dragon Systems is developing and building high performance, computationally-efficient interactive speech workstations, to support adaptive speech recognition of large vocabulary, natural language speech input in real-time. These systems are based on the results of the multi-knowledge source (MKS) algorithm architecture and multi-processor accelerator hardware studies previously undertaken by Dragon under DARPA auspices, and on Dragon's separately developed speech recognition systems (VoiceScribe, DragonWriter, and DragonDictate) and related work.