ppxscal/embedding_network huggingface dataset:
Effect of communication overheads on Time Warp performance: an experimental study
Authors: Christopher D. Carothers, Richard M. Fujimoto, Paul England
Venue: ACM SIGSIM Simulation Digest (1994)

This paper describes results of an empirical study to evaluate the effect of communications delays on the performance of the Time Warp mechanism in order to assess the effectiveness of Time Warp in distributed computing environments. An implementation of Time Warp on a collection of networked workstations is used in this study. Performance using synchronous and asynchronous message passing primitives are compared, and it is observed that Time Warp experiences much more rolled back computation when using the synchronous primitives for certain applications. Message passing is decomposed into a computation component at the sender and receiver processors, and a transmission delay component that represents the amount of time the message remains &ldquo;in transit&rdquo; within the network. The effect of each of these components on Time Warp performance is studied. It is observed that communications latency in distributed computing environments can significantly degrade the efficiency of Time Warp for applications containing large numbers of simulator objects with small event granularity (by increasing the amount of rolled back computation), particularly applications using &ldquo;self-driving&rdquo; simulator objects. However, for applications containing large grained events, communication delay appears to have little effect on rollback behavior in Time Warp.
Nonzero structure analysis
Authors: Aart J. C. Bik, Harry A. G. Wijshoff
Venue: Proceedings of the 8th international conference on Supercomputing (1994)

Because the efficiency of sparse codes is very much dependent on the size and structure of input data, peculiarities of the nonzero structures of sparse matrices must be accounted for in order to avoid unsatisfying performance. Usually, this implies retargeting a sparse application to specific instances of the same problem. However, if characteristics of the input data are collected at compile-time and used in the data structure selection and code generation by a compiler that converts dense programs into sparse programs automatically, the complexity of sparse code development can be greatly reduced, and an efficient way for this retargeting results. Such a &ldquo;sparse compiler&rdquo; requires an analysis engine, which is the topic of this paper.
The structure of work perceptions among Hong Kong and United States IS professionals: a multidimensional scaling test of the Hofstede cultural paradigm
Authors: Norman B. Bryan,  Jr., Ephraim R. McLean, Stanley J. Smits, Janice Burn
Venue: Proceedings of the 1994 computer personnel research conference on Reinventing IS : managing information technology in changing organizations: managing information technology in changing organizations (1994)

Hong Kong and United States Information Specialist (IS) professionals' perceptions of work are analyzed according to Hofstede's cultural paradigm. More specifically, the theoretical emphasis of this research is a test of the cultural divergence hypothesis as it relates to the individualism/collectivism dimension of Hofstede's analysis. Further, smallest space analysis, a multidimensional scaling technique, is used to assess the differences between the two cultures. In general, the hypothesized differences between the two cultures is supported, Hong Kong and United States IS professionals differ along the affective facet of work perceptions. Implications of the findings are discussed.
Information systems and total quality management: establishing the link
Authors: Omar E. M. Khalil
Venue: Proceedings of the 1994 computer personnel research conference on Reinventing IS : managing information technology in changing organizations: managing information technology in changing organizations (1994)

Many Total quality Management (TQM) implementations have failed to achieve the long-term, substantial gains promised by TQM proponents. Scholars and practitioners blame these failures on different causes which can be linked either directly or indirectly to insufficient support by information systems (IS) to TQM efforts. While IS is a key part of the infrastructure for TQM, its supporting role has not received much attention in the mostly prescriptive TQM literature. IS and TQM share a considerable degree of commonality in their end objectives and in their underlying philosophies and management systems. Their success hinges on the effective planning and implementation of each. This paper introduces a proposed framework to establish a link between the two. The two approaches appear to be entirely compatible and capable of being combined into a composite model of action for an organization seeking to maximize its competitive position.
Some human interaction issues in computer algebra
Authors: Norbert Kajler, Neil Soiffer
Venue: ACM SIGSAM Bulletin (1994)

This paper addresses some of the current issues concerning the improvement of user interfaces for computer algebra systems. Some state of the art commercial software as well as research prototypes are presented, followed by a description of present research directions.
Version 2.0 of the OASIS system available for distribution
Authors: Kris Kozminski, Carson Stuart
Venue: ACM SIGDA Newsletter (1992)

OASIS (Open Architecture Silicon Implementation Software) is a comprehensive standard cell-based VLSI synthesis system. It comprises four major components: the compiler and logic synthesizer, the simulator and verifier, the automatic test pattern generator, and the automatic layout generator.
Automatic generation of production rules for integrity maintenance
Authors: Stefano Ceri, Piero Fraternali, Stefano Paraboschi, Letizia Tanca
Venue: ACM Transactions on Database Systems (TODS) (1994)

In this article we present an approach to integrity maintenance, consisting of automatically generating production rules for integrity enforcement. Constraints are expressed as particular formulas of Domain Relational Calculus; they are automatically translated into a set of repair actions, encoded as production rules of an active database system. Production rules may be redundant (they enforce the same constraint in different ways) and conflicting (because repairing one constraint may cause the violation of another constraint). Thus, it is necessary to develop techniques for analyzing the properties of the set of active rules and for ensuring that any computation of production rules after any incorrect transaction terminates and produces a consistent database state.Along these guidelines, we describe a specific architecture for constraint definition and enforcement. The components of the architecture include a Rule Generator, for producing all possible repair actions, and a Rule Analyzer and Selector, for producing a collection of production rules such that their execution after an incorrect transaction always terminates in a consistent state (possibly by rolling back the transaction); moreover, the needs of applications are modeled, so that integrity-enforcing rules reach the final state that better represents the original intentions of the transaction's supplier. Specific input from the designer can also drive the process and integrate or modify the rules generated automatically by the method. Experimental results of a prototype implementation of the proposed architecture are also described.
Second-order surface analysis using hybrid symbolic and numeric operators
Authors: Gershon Elber, Elaine Cohen
Venue: ACM Transactions on Graphics (TOG) (1993)

Results from analyzing the curvature of a surface can be used to improve the implementation, efficiency, and effectiveness of manufacturing and visualization of sculptured surfaces. We develop a robust method using hybrid symbolic and numeric operators to create trimmed surfaces, each of which is solely convex, concave, or saddle and partitions the original surface. The same method is also used to identify regions whose curvature lies within prespecified bounds.
An integrated Prolog programming environment
Authors: U. Schreiweis, A. Keune, H. Langendörfer
Venue: ACM SIGPLAN Notices (1993)

For a long time it has been argued that the right kind of representation can provide insight and understanding for a problem. Believing in the general hypothesis that the limitations of our thoughts are all too often identical with the limits of our imagination and visualization capabilities, we have developed a Prolog visualization concept based on a module interconnection graph. This approach provides support for the construction of Prolog systems out of modules (programming-in-the-large). In the approach described below we present an integrated Prolog programming environment based on special features of our hypertext system KnowS. Beyond these features are typed links, node classes, and transfer modules allowing dataflow between several components. But a program is not only a static object. To study the details of a program, we really have to see it in operation. Therefore we also provide animation of program execution. We are convinced that our integrated approach of managing sources of different kinds of information, supporting their structuring and the facility to maintain a Prolog program by hypertext nodes and links is an important step to the integration of software engineering environments and hypertext systems.
Types for the working programmer (abstract)
Authors: Andrew Black
Venue: ACM SIGPLAN OOPS Messenger (1993)

Types for the Working Programmer Andrew Black, DEC There has been recent progress in understanding types for object-oriented languages, but most of it has had little or no impact on real programmers. This tutorial aims to extract from the confusion those topics that are important to programmers who must use or choose an object-oriented language. The tutorial explains the role of types in object-oriented languages, what types can do for programmers, and how the trend towards distributed and heterogeneous systems and object-oriented databases influences what it means for a program to be type-correct. The tutorial describes the difference between objects and values, what types are and why they are good for you, what refinement and subtyping are, what problems they solve, and what problems they do not; why contravariance isnt an unnatural act; why inheritance is a relationship between programs, not between classes. By the end of the tutorial, you will understand how abstract concepts like subtyping can help you solve practical problems such as deciding when one piece of code can be substituted for another.
Analyzing multiprocessor cache behavior through data reference modeling
Authors: Jory Tsai, Anant Agarwal
Venue: ACM SIGMETRICS Performance Evaluation Review (1993)

This paper develops a data reference modeling technique to estimate with high accuracy the cache miss ratio in cache-coherent multiproeessors. The technique involves analyzing the dynamic data referencing behavior of parallel algorithms. Data referenee modeling first identifies different types of shared data blocks accessed during the execution of a parallel algorithm, then captures in a few parameters the cache behavior of each shared block as a function of the problem size, number of processors, and cache line size, and finally constructs an analytical expression for each algorithm to estimate the cache miss ratio. Because the number of processors, problem size, and cache line size are included as parameters, the expression for the each miss ratio can be used to predict the performance of systems with different configurations. Six parallel algorithms are studied, and the analytical results compared against previously published simulation results, to establish the confidence level of the data reference modeling technique. It is found that the average prediction error for four out of six algorithms is within five percent and within ten percent for the other two. The paper also derives from the model several results on how cache miss rates scale with system size.
Random Walks in Weyl Chambers and the Decomposition of Tensor Powers
Authors: David J. Grabiner, Peter Magyar
Venue: Journal of Algebraic Combinatorics: An International Journal (1993)

We consider a class of random walks on a lattice, introduced by Gessel and Zeilberger, for which the reflection principle can be used to count the number of k-step walks between two points which stay within a chamber of a Weyl group. We prove three independent results about such &ldquo;reflectable walks&rdquo;: first, a classification of all such walks&semi; second, many determinant formulas for walk numbers and their generating functions&semi; third, an equality between the walk numbers and the multiplicities of irreducibles in the kth tensor power of certain Lie group representations associated to the walk types. Our results apply to the defining representations of the classical groups, as well as some spin representations of the orthogonal groups.
Endian-independent record representation clauses
Authors: Norman H. Cohen
Venue: ACM SIGAda Ada Letters (1994)

Ada-83 record representation clauses can be written in a way that confines dependence on the compiler's bit-numbering scheme to a few lines of the program.
Parity logging disk arrays
Authors: Daniel Stodolsky, Mark Holland, William V. Courtright,  II, Garth A. Gibson
Venue: ACM Transactions on Computer Systems (TOCS) (1994)

Parity-encoded redundant disk arrays provide highly reliable, cost-effective secondary storage with high performance for reads and large writes. Their performance on small writes, however, is much worse than mirrored disks&mdash;the traditional, highly reliable, but expensive organization for secondary storage. Unfortunately, small writes are a substantial portion of the I/O workload of many important, demanding applications such as on-line transaction processing. This paper presents parity logging, a novel solution to the small-write problem for redundant disk arrays. Parity logging applies journalling techniques to reduce substantially the cost of small writes. We provide detailed models of parity logging and competing schemes&mdash;mirroring, floating storage, and RAID level 5&mdash;and verify these models by simulation. Parity logging provides performance competitive with mirroring, but with capacity overhead close to the minimum offered by RAID level 5. Finally, parity logging can exploit data caching more effectively than all three alternative approaches.
The pragmatics of building object-oriented systems (abstract)
Authors: Grady Booch
Venue: ACM SIGPLAN OOPS Messenger (1993)

The Pragmatics of Building Object-Oriented Systems Grady Booth, Rational This tutorial expands upon the process described in Booths Object-Oriented Design with Applications to provide a prescriptive, iterative process for object-oriented development. It describes both the macro and micro process of development. It gives guidelines for managing iterative development, and addresses the pragmatic issues of milestones and planning, staffing, integration and release management, reuse, testing, quality assurance and metrics, documentation, tools, and technology transfer. This tutorial assumes that you are familiar with Booths design method.
Point-wise calculus
Authors: Walter G. Spunde
Venue: ACM SIGAPL APL Quote Quad (1993)

The work of Richard Neidinger implementing automatic differentiation in APL as a vector arithmetic is reformulated and extended. For functions of a single variable, an arithmetic is developed for function samples, nested vectors whose components hold the values, at any number of given sample points, of a function and its derivatives up to any specified order. It is argued that, for teaching purposes, this sampling provides a more intuitive introduction to mathematical functions and the rules of calculus than do algebraic formulae and that for certain calculations (such as the computation of polynomial approximations of high degree) the formulation provides superior algorithms for computation. As such, it offers an alternative approach to the teaching of elementary college mathematics.
On the relative cost of sampling for join selectivity estimation
Authors: Peter J. Haas, Jeffrey F. Naughton, Arun N. Swami
Venue: Proceedings of the thirteenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems (1994)

We compare the cost of estimating the selectivity of a &ldquo;star join&rdquo; using sampling procedure t-cross to the cost of simply computing the join and obtaining the exact answer. Our bounds and approximations for the relative cost of sampling show how this cost depends on the size of the input relations, the number of input relations, and the precision criterion used by the estimation procedure. We also demonstrate the deleterious effect of dangling tuples and the mixed effect of data skew on the relative cost of sampling. These results provide insight into when sampling should or should not be used for join selectivity estimation.
Semantic representations and query languages for or-sets
Authors: Leonid Libkin, Limsoon Wong
Venue: Proceedings of the twelfth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems (1993)

Or-sets were introduced by Imielinski, Naqvi and Vadaparty for dealing with limited forms of disjunctive information in database queries. Independently, Rounds used a similar notion for representing disjunctive and conjunctive information in the context of situation theory. In this paper we formulate a query language with adequate expressive power for or-sets. Using the notion of normalization of or-sets, queries at the &ldquo;structural&rdquo; and &ldquo;conceptual&rdquo; levels are distinguished. Losslessness of normalization is established for a large class of queries. We have obtained upper bounds for the cost of normalization. An approach related to that of Rounds is used to provide semantics for or-sets.
A comparison of adaptive wormhole routing algorithms
Authors: Rajendra V. Boppana, Suresh Chalasani
Venue: Proceedings of the 20th annual international symposium on Computer architecture (1993)

Improvement of message latency and network utilization in torus interconnection networks by increasing adaptivity in wormhole routing algorithms is studied. A recently proposed partially adaptive algorithm and four new fully-adaptive routing algorithms are compared with the well-known e-cube algorithm for uniform, hotspot, and local traffic patterns. Our simulations indicate that the partially adaptive north-last algorithm, which causes unbalanced traffic in the network, performs worse than the nonadaptive e-cube routing algorithm for all three traffic patterns. Another result of our study is that the performance does not necessarily improve with full-adaptivity. In particular, a commonly discussed fully-adaptive routing algorithm, which uses 2n virtual channels per physical channel of a k-ary n-cube, performs worse than e-cube for uniform and hotspot traffic patterns. The other three fully-adaptive algorithms, which give priority to messages based on distances traveled, perform much better than the e-cube and partially-adaptive algorithms for all three traffic patterns. One of the conclusions of this study is that adaptivity, full or partial, is not necessarily a benefit in wormhole routing.
File service for SIGDOC 93: function, structure, content
Authors: Paul Beam, Travis Capener, Sanjay Singh
Venue: ACM SIGDOC Asterisk Journal of Computer Documentation (1993)

Throughout this article we will refer to information sources or tools resident on sigdoc-1 and other systems by a in the text. These are all available at the addresses shown in the first diagram. In the movement from print to electronic communications they illustrate many standard features of basic networking, serve as a general guide to getting started and illustrate many of our arguments. All three of us retain our commitments to ink-on-paper and regard many electronic expressions as "extensions of convenience" on a spectrum of communications.
An instability problem in Chebyshev expansions for special functions
Authors: Allan MacLeod
Venue: ACM SIGNUM Newsletter (1993)

For the last 2 or 3 years, I have been developing a software package MISCFUN which evaluates mathematical functions not found in the standard libraries such as NAG or IMSL, or in public-domain packages such as SPECFUN or FNLIB.
An Analysis of Test Data Selection Criteria Using the RELAY Model of Fault Detection
Authors: Debra J. Richardson, Margaret C. Thompson
Venue: IEEE Transactions on Software Engineering (1993)

RELAY is a model of faults and failures that defines failure conditions, which describe test data for which execution will guarantee that a fault originates erroneous behavior that also transfers through computations and information flow until a failure is revealed. This model of fault detection provides a framework within which other testing criteria's capabilities can be evaluated. Three test data selection criteria that detect faults in six fault classes are analyzed. This analysis shows that none of these criteria is capable of guaranteeing detection for these fault classes and points out two major weaknesses of these criteria. The first weakness is that the criteria do not consider the potential unsatisfiability of their rules. Each criterion includes rules that are sufficient to cause potential failures for some fault classes, yet when such rules are unsatisfiable, many faults may remain undetected. Their second weakness is failure to integrate their proposed rules.
The cedar system and an initial performance study
Authors: D. Kuck, E. Davidson, D. Lawrie, A. Sameh, C. Q. Zhu, A. Veidenbaum, J. Konicek, P. Yew, K. Gallivan, W. Jalby, H. Wijshoff, R. Bramley, U. M. Yang, P. Emrath, D. Padua, R. Eigenmann, J. Hoeflinger, G. Jaxon, Z. Li, T. Murphy, J. Andrews
Venue: Proceedings of the 20th annual international symposium on Computer architecture (1993)

In this paper, we give an overview of the Cedar multiprocessor and present recent performance results. These include the performance of some computational kernels and the Perfect Benchmarks. We also present a methodology for judging parallel system performance and apply this methodology to Cedar, Cray YMP-8, and Thinking Machines CM-5.
On the problems of information technology management in developing nations
Authors: Adnan H. Yahya
Venue: Proceedings of the 1993 conference on Computer personnel research (1993)

Many developing nations treat information technology as a high priority item in their economic planning. The pace of computer introduction and the span of computer-based systems are expanding rapidly. This emanates from the realization that information technology has a great potential for the economic development of third world countries. However, it is our view that while information technology products open new opportunities for developing countries they also pose a new set of challenges. The often poorly managed computer resources tend to complicate the decision making process due to the introduction of new uncertainties. The problems of the industrial and communications infrastructure, personnel issues, political and social factors are important elements hampering the sound management of information technology resources in many developing nations. After giving some background material on characteristics of the computerization process in developing countries this paper discusses the manifestations of information technology mismanagement, the factors hampering the proper management of computer resources in a developing nation context and points to some of the potential solutions to these problems based on the experience of several nations in this field.