ppxscal/embedding_network huggingface dataset:
An abstract model of rollback recovery control in distributed systems
Authors: Jiannong Cao, K. C. Wang
Venue: ACM SIGOPS Operating Systems Review (1992)

This paper develops an abstract model which presents a method of uniform description of different rollback recovery control algorithms for distributed systems. We first developed a general definition of the distributed rollback recovery control problem. The concept of a distributed recovery control system (DRC system), consisting of distributed recovery control units (DRC units), is proposed to model recovery with various control granularities. Then, we developed a graph model, called dependency graph, for distributed rollback recovery control algorithms. An atomic subgraph is defined as a subgraph induced by a set of nodes which has no outgoing arcs to other nodes in the graph. Committing and aborting atomic actions can be modeled as identifying atomic subgraphs. Next, we defined two kinds of dependency graphs: checkpoint graphs and unit graphs, based on the dependency relation defined by rollback propagation. We have shown that various types of distributed recovery control algorithms can be classified based on the identifications of atomic subgraphs in these two graphs. Therefore, using the model may allow us to describe existing algorithms in a uniform way and, more importantly, to find new algorithms.
Computational intelligence in CAD/CAM applications
Authors: Chaman L. Sabharwal, Thomas G. Melson, Martin D. Fraser
Venue: Proceedings of the 1990 ACM annual conference on Cooperation (1990)

This paper presents a fundamental, direct, and powerful approach to the surface/surface intersection problem in CAD/CAM applications. The algorithm is designed and implemented in three steps: a) Preprocessing - locate the potentially intersecting sections of the surfaces and decompose the surfaces into surface elements within specified flatness tolerance; b) Intersection- decompose the possibly intersecting pairs of surface elements into continuous surface triangulations to find the approximate intersections between the pairs of surface elements; c) Postprocessing- assemble the intersection primitives into curves of intersection, refine the accuracy of computed intersection points, and compact the intersection curves. This surface/surface intersection algorithm is applicable to the widest class, Co, of parametric surfaces, an enhancement over the existing algorithms applicable to only Ck, k &ge; 1, surfaces. This implementation, based on computational intelligence, requires no human interaction for intersection curve pattern recognition.
Figures of merit: the sequel
Authors: Martin Tompa
Venue: ACM SIGACT News (1990)

Science has marched on despite the appearance of the original "Figures of Merit" [18]. The purpose of this survey is to bring the community up to date on the most recent bounds, so that we may collaborate to improve them.
Handling missing data by using stored truth values
Authors: G. H. Gessert
Venue: ACM SIGMOD Record (1991)

This paper proposes a method for handling inapplicable and unknown missing data. The method is based on: (1) storing default values (instead of null values) in place of missing data, (2) storing truth values that describe the logical status of the default values in corresponding fields of corresponding tables. Four valued logic is used so that the logical status of the default data values can be described as, not just true or false, but also as inapplicable or unknown. This method, in contrast to the &ldquo;hidden byte&rdquo; approach, has two important advantages: (1) Because the logical status of all data is represented explicitly in tables, all 4-valued operations can be handled via a 2-valued data manipulation language, such as SQL. Language extensions for handling missing data (e.g., &ldquo;IS NULL&rdquo;) are not necessary. (2) Because data fields always contain a default value (as opposed to a null value or mark), it is possible to do arithmetic across missing data and to interpret the logical status of the result by means of logical operations on the corresponding stored truth values.
Systolic implementations of a move-to-front text compressor
Authors: Clark D. Thomborson, Belle W.-Y. Wei
Venue: ACM SIGARCH Computer Architecture News (1991)

We give systolic implementations for three variants of the move-to-front coding algorithm discussed in recent journal articles by Ryabko, Elias, and Bentley, Sleator, Tarjan, and Wei. Our intent is to make a simple high-speed text-compression system for both data transmission and data storage devices. Comparing our implementations with previously-proposed software and hardware devices for these applications, we conclude that our implementations should operate at much higher bandwidth than any known high-compression algorithm, and at higher bandwidth and comparable compression to the Lempel-Ziv-Welch and Smith-Storer hardware.
Automating Visual Language Generation
Authors: Claudia Crimi, Angela Guercio, Giuliano Pacini, Genoveffa Tortora, Maurizio Tucci
Venue: IEEE Transactions on Software Engineering (1990)

A system to generate and interpret customized visual languages in given application areas is presented. The generation is highly automated. The user presents a set of sample visual sentences to the generator. The generator uses inference grammar techniques to produce a grammar that generalizes the initial set of sample sentences, and exploits general semantic information about the application area to determine the meaning of the visual sentences in the inferred language. The interpreter is modeled on an attribute grammar. A knowledge base, constructed during the generation of the system, is then consulted to construct the meaning of the visual sentence. The architecture of the system and its use in the application environment of visual text editing (inspired by the Heidelberg icon set) enhanced with file management features are reported.
Developing a theory to guide the process of designing information retrieval systems
Authors: Diane H. Sonnenwald
Venue: Proceedings of the 15th annual international ACM SIGIR conference on Research and development in information retrieval (1992)

The dominant approaches to information retrieval system design are based on rational theory and cognitive engineering. However, these theories as well as approaches in other disciplines, reviewed in this paper, do not account for communication, or interaction, among design participants which is critical to design outcomes. This research attempts to develop a descriptive design model that accounts for communication among users, designers, and developers throughout the design process. A pilot study has been completed and a preliminary model that represents a first step in understanding participants' evolving perceptions and expectations of the design process and its outcomes is described in this paper.
A Two-Stage Algorithm for Discontinuity-Preserving Surface Reconstruction
Authors: Sarvajit S. Sinha, Brian G. Schunck
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1992)

A two-stage algorithm for visual surface reconstruction from scattered data while preserving discontinuities is presented. The first stage consists of a robust local approximation algorithm (the moving least median of squares (MLMS) of error) to clean the data and create a grid from the original scattered data points. This process is discontinuity preserving. The second stage introduces a weighted bicubic spline (WBS) as a surface descriptor. The WBS has a factor in the regularizing term that adapts the behavior of the spline across discontinuities. The weighted bicubic approximating spline can approximate data with step discontinuities with no discernible distortion in the approximating surface. The combination of robust surface fitting and WBSs removes outliers and reduces Gaussian noise. Either stage by itself would not effectively remove both kinds of noise. Experimental results with the two-stage algorithm are presented.
Authentication in distributed systems: theory and practice
Authors: Butler Lampson, Martín Abadi, Michael Burrows, Edward Wobber
Venue: ACM Transactions on Computer Systems (TOCS) (1992)

We describe a theory of authentication and a system that implements it. Our theory is based on the notion of principal and a &ldquo;speaks for&rdquo; relation between principals. A simple principal either has a name or is a communication channel; a compound principal can express an adopted role or delegated authority. The theory shows how to reason about a principal's authority by deducing the other principals that it can speak for; authenticating a channel is one important application. We use the theory to explain many existing and proposed security mechanisms. In particular, we describe the system we have built. It passes principals efficiently as arguments or results of remote procedure calls, and it handles public and shared key encryption, name lookup in a large name space, groups of principals, program loading, delegation, access control, and revocation.
Timing analysis in precharge/unate networks
Authors: Patrick C. McGeer, Robert K. Brayton
Venue: Proceedings of the 27th ACM/IEEE Design Automation Conference (1991)

We consider the false path problem on precharge/unate networks, more commonly known as dynamic CMOS networks. We demonstrate that the tight criterion of dynamic sensitization is robust on such networks, though it has been shown to be non-robust on general networks. Tighter bounds may be obtained on the length of the critical path in precharge/unate networks than in general static networks. We derive a dynamic programming procedure to find the longest dynamically sensitizable path in a precharge/unate network.
General Schedulers for the Pinwheel Problem Based on Double-Integer Reduction
Authors: Mee Yee Chan, Francis Y. L. Chin
Venue: IEEE Transactions on Computers (1992)

The pinwheel is a hard-real-time scheduling problem for scheduling satellite ground stations to service a number of satellites without data loss. Given a multiset of positive integers (instance) A=(a/sub 1/, . . . a/sub n/), the problem is to find an infinite sequence (schedule) of symbols from (1,2, . . . n) such that there is at least one symbol i within any interval of a/sub i/ symbols (slots). Not all instances A can be scheduled; for example, no 'successful' schedule exists for instances whose density is larger than 1. It has been shown that any instance whose density is less than 2/3 can always be scheduled. Two new schedulers are proposed which improve this 2/3 result to a new 0.7 density threshold. These two schedulers can be viewed as a generalization of the previously known schedulers, i.e. they can handle a larger class of pinwheel instances including all instances schedulable by the previously known techniques.
Growth estimates for exp¿log functions
Authors: John Shackell
Venue: Journal of Symbolic Computation (1990)

Exp-log functions are those obtained from the constant 1 and the variable X by means of arithmetic operations and the function symbols exp() and log@?. This paper gives an explicit algorithm for determining eventual dominance of these functions modulo an oracle for deciding zero equivalence of constant terms, This also provides another proof that the dominance problem for exp-log functions is Turing-reducible to the identity problem for constant terms.
Cyclomatic Complexity Density and Software Maintenance Productivity
Authors: Geoffrey K. Gill, Chris F. Kemerer
Venue: IEEE Transactions on Software Engineering (1991)

A study of the relationship between the cyclomatic complexity metric (T. McCabe, 1976) and software maintenance productivity, given that a metric that measures complexity should prove to be a useful predictor of maintenance costs, is reported. The cyclomatic complexity metric is a measure of the maximum number of linearly independent circuits in a program control graph. The current research validates previously raised concerns about the metric on a new data set. However, a simple transformation of the metric is investigated whereby the cyclomatic complexity is divided by the size of the system in source statements. thereby determining a complexity density ratio. This complexity density ratio is demonstrated to be a useful predictor of software maintenance productivity on a small pilot sample of maintenance projects.
A maple program that finds, and proves, recurrences and differential equations satisfied by hyperexponential definite integrals
Authors: Gert Almkvist, Doron Zeilberger
Venue: ACM SIGSAM Bulletin (1991)

In [A-Z] we described an algorithm that given a hyperexponential function of two variables F(x,y), produces a differential equation satisfied by[EQUATION]
On Unordered Codes
Authors: Bella Bosa
Venue: IEEE Transactions on Computers (1991)

By extending the results obtained by D. E. Knuth (1986), a parallel unordered coding scheme with 2/sup r/ information bits is described. Balanced codes in which each codeword contains equal amounts of zeros and ones, with r check bits and up to 2/sup r+1/-(r+2) information bits, are constructed. Unordered codes with r check bits and up to 2/sup r/+2/sup r-1/-1 information bits are designed. Codes capable of detecting 2/sup r-1/+(2/sup r//2)-1 unidirectional errors using r check bits are also described. A review of previous work is presented.
Large-scale computing on clustered vector multiprocessors
Authors: A. Kamel, P. Sguazzero, V. Zecca
Venue: Proceedings of the 1990 ACM/IEEE conference on Supercomputing (1990)

A two-level parallel implementation of a large scale geophysical simulation code is presented. The software/hardware environment consists of the IBM Clustered FORTRAN, an extension of FORTRAN, allowing a single application program to execute concurrently on two IBM 3090 computers (first level of parallelism) while exploiting the multiple vector processors of each 3090 system (second level of parallelism). The experiments reported show that the problem is characterized by large task granularity and small communication/computation ratio, thus leading to sustained parallel speed-ups of nearly ten on a cluster of two 3090 computers, totaling twelve vector processors.
Hamming numbers, lazy evaluation, and eager disposal
Authors: C. K. Yuen
Venue: ACM SIGPLAN Notices (1992)

The generation of Hamming numbers is used as a case study for discussing storage management for transient data structures in language processors.
Supercomputing policy links science and the &ldquo;C&rdquo; word
Authors: Diane Crawford
Venue: Communications of the ACM (1991)

Competition, a concept nary whispered in pure science circles, might just have been the catalyst that finally drove the High Performance Computing and Communication (HPCC) policy over the Hill. It has taken many years, and countless government studies, to help legislators even comprehend and appreciate the potential of high-performance computing technology in the U.S. But toss in the competitive angle, and the story needs little translation.
The universe of design is unfolding (as it should!)
Authors: Jim Carter
Venue: ACM SIGCHI Bulletin (1990)

This is a brief report of the discussion in one of the subgroups from the "Taking Design Seriously" Workshop at CHI'90. The "Cosmic Glue" subgroup organized around the concept that there needs to be something at a higher level than the "Design Process(es) of HCI". This higher "Cosmic Glue" should lead towards systems that actually (rather than only theoretically) satisfy their users and their purposes for being.
Speaker adaptation from limited training in the BBN BYBLOS Speech Recognition system
Authors: Francis Kubala, Ming-Whei Feng, John Makhoul, Richard Schwartz
Venue: Proceedings of the workshop on Speech and Natural Language (1989)

The BBN BYBLOS continuous speech recognition system has been used to develop a method of speaker adaptation from limited training. The key step in the method is the estimation of a probabilistic spectral mapping between a prototype speaker, for whom there exists a well-trained speaker-dependent hidden Markov model (HMM), and a target speaker for whom there is only a small amount of training speech available. The mapping defines a set of transformation matrices which are used to modify the parameters of the prototype model. The resulting transformed model is then used as an approximation to a well-trained model for the target speaker. We review the techniques employed to accomplish this transformation and present experimental results conducted on the DARPA Resource Management database.
Varying length strings in Fortran
Authors: J. L. Schonfelder
Venue: ACM SIGPLAN Fortran Forum (1992)

This International Standard has been prepared by ISO/IEC JTC1/SC22/WG5, the technical working group for the Fortran language. This International Standard is a collateral standard to ISO/IEC 1539:1991, which defines the latest revision of the Fortran language, known informally as Fortran 90.
QBD*: A Graphical Query Language with Recursion
Authors: Michele Angelaccio, Tiziana Catarci, Giuseppe Santucci
Venue: IEEE Transactions on Software Engineering (1990)

A system to query databases using diagrams as a standard user interface is proposed. The system, called Query by Diagram* (QBD*), makes use of a conceptual data model, a query language on this model, and a graphical user interface. The conceptual model is the entity-relationship model. The query language, whose expressive power allows recursive queries, supports visual interaction. The main characteristics of the interface are ease of use and the availability of a rich set of primitives for schema selection and query formulation. The expressive power of QBD* and G/sup +/, which are the only languages allowing recursive queries to be expressed graphically are compared.
Randomized mutual exclusion algorithms revisited
Authors: Eyal Kushilevitz, Michael O. Rabin
Venue: Proceedings of the eleventh annual ACM symposium on Principles of distributed computing (1992)

In [4] a randomized algorithm for mutual exclusion with bounded waiting, employing a logarithmic sized shared variable, was given. Saias and Lynch [5] pointed out that the adversary scheduler postulated in the above paper can observe the behavior of processes in the interval between an opening of the critical section and the next closing of the critical section. it can then draw conclusions about values of their local variables as well as the value of the randomized round number component of the shared variable, and arrange the schedule so as to discriminate against a chosen process. This invalidates the claimed properties of the algorithm. In the present paper the algorithm in [4] is modified, using the ideas of [4], so as to overcome this difficulty, obtaining essentially the same results. Thus, as in [4], randomization yields simple algorithms for mutual-exclusion with bounded waiting, employing a shared variable of considerably smaller size than the lower-bound established in [1] for deterministic algorithms.
Technology transfer: experiences in introducing object-oriented methods to government projects
Authors: John A. Anderson, Elaine S. Ward
Venue: Proceedings of the eighth annual Washington Ada symposium summer SIGAda meeting on Ada: software: foundation for competitveness (1991)

This paper describes the challenges and solutions encountered while introducing and refining a comprehensive object-oriented life-cycle methodology to government deliverable projects. The paper focuses on techniques that have promoted efficient, two-way technology transfer between development teams and a methodology process group cooperatively applying object-oriented requirements analysis and design methods. These experiences have resulted in efficiently documenting an effective repeatable development process. Many of the techniques incorporate the concepts of Total Quality Management (TQM), such as a focus on the customer, management commitment and leadership, employee and team involvement, reliance on process standards and measurement, and continual improvement.
A User Friendly Software Environment for Protocol Synthesis
Authors: Norio Shiratori, Yao-Xue Zhang, Kaoru Takahashi, Shoichi Noguchi
Venue: IEEE Transactions on Computers (1991)

An attempt is made to design a user-friendly software environment for protocol synthesis based on the FSM (finite state machine), and to show the validity of applying AI (artificial intelligence) techniques to the construction of such a system. For that purpose, the authors have first designed a user-friendly software environment, named SEPS, using the programming language C, which belongs to the procedural programming paradigm. The aim of SEPS is to help a protocol designer to easily design a protocol and avoid logical errors like unspecified receptions and state deadlocks. In order to enhance the productivity of protocol development, a user-friendly interface has been designed which employs the multiwindow mechanism and provides the graphic tools in this system. Consequently, a protocol designer without any experience in protocol synthesis can easily design a protocol without logical errors. The authors have also designed a knowledge-based software environment for protocol synthesis, named KSPS, using the expert system tool OPS83. KSPS has the same functions as SEPS. The advantages of KSPS over SEPS in terms of extension, modification, and maintenance of protocol development systems are shown.
On the Assignment Problem of Arbitrary Process Systems to Heterogeneous Distributed Computer Systems
Authors: Nicholas S. Bowen, Christos N. Nikolaou, Arif Ghafoor
Venue: IEEE Transactions on Computers (1992)

The authors propose and evaluate an efficient hierarchical clustering and allocation algorithm that drastically reduces the interprocess communications cost while observing lower and upper bounds of utilization for the individual processors. They compare the algorithm with branch-and-bound-type algorithms that can produce allocations with minimal communication cost, and show a very encouraging time complexity/suboptimality tradeoff in favor of the algorithm, at least for a class of process clusters and their random combinations which it is believed occur naturally in distributed applications. The heuristic allocation is well suited for a changing environment, where processors may fail or be added to the system and where the workload patterns may change unpredictably and/or periodically.
Adaptive dictionary matching
Authors: Amihood Amir, Martin Farach
Venue: Proceedings of the 32nd annual symposium on Foundations of computer science (1991)

Semiadaptive and fully adaptive dictionary matching algorithms are presented. In the fully adaptive algorithm, the dictionary is processed in time O( mod D mod log mod D mod ). Inserting a new pattern P/sub k+1/ into the dictionary can be done in time O mod P/sub K+1/ mod log mod D mod ). A dictionary pattern can be deleted in time O(log mod D mod ). Text scanning is accomplished in time O( mod T mod log mod D mod ). Also presented is a parallel version of the algorithm with optimal speedup for the dictionary construction and pattern addition phase and a logarithmic overhead in the text scan phase. The method used incorporates a new way of using suffix trees as well as a new data structure in which the suffix tree is embedded for the sequential algorithm.
Partial parsing: a report on work in progress
Authors: Ralph Weischedel, Damaris Ayuso, R. Bobrow, Sean Boisen, Robert Ingria, Jeff Palmucci
Venue: Proceedings of the workshop on Speech and Natural Language (1991)

This paper reports a handful of experiments designed to test the feasibility of applying well-known partial parsing techniques to the problem of automatic data base update from an open-ended source of messages. and the feasiblity of automatically learning semantic knowledge from annotated examples. The challenges arise from the incompleteness of any lexicon, sentences that average over 20 words in length, and the lack of a complete semantics.