ppxscal/embedding_network huggingface dataset:
Original Contribution: Averaged neural networks
Authors: T. A. Burton
Venue: Neural Networks (1993)

Cohen and Grossberg studied an almost gradient system of ordinary differential equations with application to neural networks and used a Liapunov function, together with an invariance principle, to show that some equilibrium points attract solutions. Independently, Hopfield modeled a neural network by means of a system of ordinary differential equations which turn out to be a special case of the Cohen-Grossberg system, as pointed out by Cohen. In the Hopfield model it is clear that the functions involved in the equations are averages and that current will flow through a synapse only if a certain threshold is reached; however, none of the models take into account an averaging technique. Investigators have been interested in sustained oscillations in neural networks and have produced them in computer simulations when there is a pointwise delay. The linearized systems with a delay have also exhibited sustained oscillations. But our conjecture is that oscillations are not caused by a delay. This paper is intended to put substance to that conjecture by examining models with both pointwise and distributed delays. None of the models have solutions with sustained oscillations.
BATCES solution #2: a simplified SA/OOD approach
Authors: Michael Hirasuna
Venue: ACM SIGAda Ada Letters (1994)

An approach to derive an Object-Oriented Design (OOD) from a simplified Structure Analysis (SA) is presented. The approach is demonstrated with the BATCES problem statement defined by the Object Oriented Work Group (OOWG) [CRA92]. Unlike other methodologies, the simplified SA/OOD is targeted specifically for Ada. Assuming that Ada is self-documenting, the approach defines the diagrams and tables that complement the code, and not just repeat the information already there. As demanded by typical Ada customers, special emphasis is placed on requirements tracing.The lack of CASE tools has been the primary argument against an Ada specific methodology. Hence, the approach only uses general productivity tools that can run on today's personal computers. Such an approach is practical because the required diagrams and tables have been greatly simplified.
Parallelizing algorithms for symbolic computation using MAPLE
Authors: Kurt Siegl
Venue: ACM SIGPLAN Notices (1993)

||MAPLE|| (speak: parallel Maple) is a portable system for parallel symbolic computation. The system is built as an interface between the parallel declarative programming language Strand and the sequential computer algebra system Maple, thus providing the elegance of Strand and the power of the existing sequential algorithms in Maple. The implementation of different parallel programming paradigms shows that it is fairly easy to parallelize even complex algebraic algorithms using this system. Sample applications (among them algorithms solving multivariate nonlinear equation systems) are implemented on various parallel architectures. For example a straightforward parallelization of the complex and important problem of real root isolation has been parallelized using a generic Strand program of fewer than 20 lines of code and a slight modification of 5 lines in the original sequential Maple source. Even with such a simple modification we gained a speed-up of 5 times, that is better than those reported by others in the literature.
On key distribution protocols for repeated authentication
Authors: Paul Syverson
Venue: ACM SIGOPS Operating Systems Review (1993)

In [KSL92], Kehne et al. present a protocol (KSL) for key distribution. Their protocol allows for repeated authentication by means of a ticket. They also give a proof in BAN logic [BAN89] that the protocol provides the principals with a reasonable degree of trust in the authentication and key distribution. They present an optimality result that their protocol contains a minimal number of messages. Nonetheless, in [NS93] Neuman and Stubblebine present a protocol (NS) as an explicit alternative to KSL that requires one less message in the initial authentication and key distribution. One goal of this paper is to examine some of the reasons for this discrepancy. Another goal is to demonstrate possible attacks on NS. Like any attacks on cryptographic protocols, these depend on assumptions about implementation details. But, when possible they are serious: a penetrator can initiate the protocol, masquerade as another principal, obtain the session key, and even generate the session key herself.1 We will set out implementation assumptions required for the attacks to take place and implementation assumptions that preclude such an attack. We will also look at other protocols, including one that is not subject to this form of attack and has the same number of messages as NS. Finally, we will briefly discuss the logical analysis of these repeat authentication protocols.
Synthesizing auditory icons
Authors: William W. Gaver
Venue: Proceedings of the INTERACT '93 and CHI '93 conference on Human factors in computing systems (1993)

Auditory icons add valuable functionality to computer interfaces, particularly when they are parameterized to convey dimensional information. They are difficult to create and manipulate, however, because they usually rely on digital sampling techniques. This paper suggests that new synthesis algorithms, controlled along dimensions of events rather than those of the sounds themselves, may solve this problem. Several algorithms, developed from research on auditory event perception, are described in enough detail here to permit their implementation. They produce a variety of impact, bouncing, breaking, scraping, and machine sounds. By controlling them with attributes of relevant computer events, a wide range of parameterized auditory icons may be created.
Ada for MS-Windows applications
Authors: Paul R. Pukite
Venue: ACM SIGAda Ada Letters (1994)

Standard Ada constructs such as package specifications, generics, tasking, and exceptions support the construction of reliable, maintainable, and reusable Microsoft Windows applications. This letter presents examples of how to use some of these constructs in the practical design of Ada programs running under Windows. These include the specification of dialog box interfaces and the use of generic packages for interapplication data exchange.
Algorithm 721: MTIEU1 and MTIEU2: two subroutines to compute eigenvalues and solutions to Mathieu's differential equation for noninteger and integer order
Authors: Randall B. Shirts
Venue: ACM Transactions on Mathematical Software (TOMS) (1993)

Two FORTRAN routines are described which calculate eigenvalues and eigenfunctions of Mathieu's differential equation for noninteger as well as integer order, MTIEU1 uses standard matrix techniques with dimension parameterized to give accuracy in the eigenvalue of one part in 1012. MTIEU2 used continued fraction techniques and is optimized to give accuracy in the eigenvalue of one part in 1014. The limitations of the algorithms are also discussed and illustrated.
Implementation of a lattice method for numerical multiple integration
Authors: Stephen Joe, Ian H. Sloan
Venue: ACM Transactions on Mathematical Software (TOMS) (1993)

An implementation of a method for numerical multiple integration based on a sequence of imbedded lattice rules is given. Besides yielding an approximation to the integral, this implementation also provides an error estimate which does not require much extra computation. The results of some numerical experiments conclude the paper.
Lightweight recoverable virtual memory
Authors: M. Satyanarayanan, Henry H. Mashburn, Puneet Kumar, David C. Steere, James J. Kistler
Venue: Proceedings of the fourteenth ACM symposium on Operating systems principles (1994)

Recoverable virtual memory refers to regions of a virtual address space on which transactional guarantees are offered. This paper describes RVM, an efficient, portable, and easily used implementation of recoverable virtual memory for Unix environments. A unique characteristic of RVM is that it allows independent control over the transactional properties of atomicity, permanence, and serializability. This leads to considerable flexibility in the use of RVM, potentially enlarging the range of applications than can benefit from transactions. It also simplifies the layering of functionality such as nesting and distribution. The paper shows that RVM performs well over its intended range of usage even though it does not benefit from specialized operating system support. It also demonstrates the importance of intra- and intertransaction optimizations.
Comparative design review: an exercise in parallel design
Authors: Jakob Nielsen, Heather Desurvire
Venue: Proceedings of the INTERACT '93 and CHI '93 conference on Human factors in computing systems (1993)

Three user interface designers were asked to design interfaces for a given problem. These designs were made available to a group of usability specialists for heuristic evaluation. The reviewers will lead off the panel with specific questions to the designers regarding the usability aspects of their designs. The panel will feature a lively discussion of the designers' various approaches and solutions.
Human Factors in the Design of an Immersive Display
Authors: Mark T. Bolas
Venue: IEEE Computer Graphics and Applications (1994)

In 1988 Fakespace began building a telepresence camera system for the Virtual Environment Workstation (View) project at NASA Ames Research Center. The complete system combined a teleoperated camera platform and 3D viewing system. Fakespace has installed descendents of this system for day-to-day use in environments ranging from research laboratories to office cubicles. By observing how people use image-generation and viewing technologies, we have evaluated the human factors involved in building and deploying effective immersive visualization systems. This article describes the application of these factors in the design of the Fakespace BOOM (Binocular Omni-Orientation Monitor). The Fakespace BOOM represents a class of immersive display devices known as counterbalanced displays. The choices that led to the design of this device apply to the design of many types of immersive displays.
Learning fixed point patterns by recurrent networks
Authors: Leong Kwan Li
Venue: Journal of Computer and System Sciences (1994)

Several learning algorithms have been derived for equilibrium points in recurrent neural networks. In this paper, we also consider learning the equilibrium points of such dynamical systems. We derive a structurally simple learning algorithm for recurrent networks which does not involve computing the trajectories of the system and we prove convergence and give examples. We also discuss solving for the connection weight matrix by iterative learning algorithms or direct solving.
Procs and locks: a portable multiprocessing platform for standard ML of New Jersey
Authors: J. Gregory Morrisett, Andrew Tolmach
Venue: Proceedings of the fourth ACM SIGPLAN symposium on Principles and practice of parallel programming (1993)

We have built a portable platform for running Standard ML of New Jersey programs on multiprocessors. It can be used to implement user-level thread packages for multiprocessors within the ML language with first-class continuations. The platform supports experimentation with different thread scheduling policies and synchronization constructs. it has been used to construct a Modula-3 style thread package and a version of Concurrent ML, and has been ported to three different multiprocessors running variants of Unix. This paper describes the platform's design, implementation, and performance.
A call to order
Authors: David Maier, Bennet Vance
Venue: Proceedings of the twelfth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems (1993)

Scientific applications are infrequent users of commercial database management systems. We feel that a key reason is they do not offer good support for ordered data structures, such as multidimensional arrays, that are needed for natural representation of many scientific data types. In this papers, we lay out issues in database support of ordered structures, consider possible approaches along with their advantages and shortcomings, and direct the reader to the wide variety of prior work outside the data management field that might be successfully applied in this endeavor.
Learning Causal Patterns: Making a Transition from Data-Driven to Theory-Driven Learning
Authors: Michael Pazzani
Venue: Machine Learning (1993)

We describe an incremental learning algorithm, called theory-driven learning, that creates rules to predict the effect of actions. Theory-driven learning exploits knowledge of regularities among rules to constrain learning. We demonstrate that this knowledge enables the learning system to rapidly converge on accurate predictive rules and to tolerate more complex training data. An algorithm for incrementally learning these regularities is described and we provide evidence that the resulting regularities are sufficiently generally to facilitate learning in new domains. The results demonstrate that transfer from one domain to another can be achieved by deliberately overgeneralizing rules in one domain and biasing the learning algorithm to create new rules that specialize these overgeneralizations in other domains.
A set of programming projects for a second programming course
Authors: Kailash Chandra
Venue: ACM SIGCSE Bulletin (1993)

A set of six related programming projects are presented. These projects are based on the assignments given to a class taking a second course in Pascal programming. The first project started with a source code of a working program assigned to the students giving them a jump start and then taking them step by step to a project where they developed a simple full-screen visual text editor. It has been a very successful experiment. It is hoped that the others can use similar programming assignments in their classes.
Overview of the Vesta parallel file system
Authors: Peter F. Corbett, Sandra Johnson Baylor, Dror G. Feitelson
Venue: ACM SIGARCH Computer Architecture News (1993)

The Vesta parallel file system provides parallel access from compute nodes to files distributed across I/O nodes in a massively parallel computer. Vesta is intended to solve the I/O problems of massively parallel computers executing numerically intensive scientific applications. Vesta has three interesting characteristics: First, it provides a user defined parallel view of file data, and allows user defined partitioning and repartitioning of files without moving data among I/O nodes. The parallel file access semantics of Vesta directly support the operations required by parallel language I/O libraries. Second, Vesta is scalable to a very large number (many hundreds) of I/O and compute nodes and does not contain any sequential bottlenecks in the data-access path. Third, it provides user-directed checkpointing of files during continuing program execution with very little processing overhead.
Digital signatures: can they be accepted as legal signatures in EDI?
Authors: Patrick W. Brown
Venue: Proceedings of the 1st ACM conference on Computer and communications security (1993)

Digital Signature (DS) technology may be employed to produce legally enforceable signatures in Electronic Data Interchange (EDI) among computer users within the same general guidelines and requirements as those developed for handwritten signatures on paper. Digital signature technology promises assurance at least equal to written signatures. From a legal standpoint, this assurance remains to be tested in the evidentiary process. Business policies for organizational use of this technology are being created as the use of digital signature technology is adopted. Standard industry practice serves to create and document a legal precedent. Digital signatures are especially applicable to interpretations of contracts and statute of fraud law. Digital signatures may be used to provide assurances in distributed and networked computer environments where electronic transactions require a high degree of trust.
Why cryptosystems fail
Authors: Ross Anderson
Venue: Proceedings of the 1st ACM conference on Computer and communications security (1993)

Designers of cryptographic systems are at a disadvantage to most other engineers, in that information on how their systems fail is hard to get: their major users have traditionally been government agencies, which are very secretive about their mistakes.In this article, we present the results of a survey of the failure modes of retail banking systems, which constitute the next largest application of cryptology. It turns out that the threat model commonly used by cryptosystem designers was wrong: most frauds were not caused by cryptanalysis or other technical attacks, but by implementation errors and management failures. This suggests that a paradigm shift is overdue in computer security; we look at some of the alternatives, and see some signs that this shift may be getting under way.
Transparency and reflection in distributed systems
Authors: Robert Stroud
Venue: ACM SIGOPS Operating Systems Review (1993)

The recursive composition of systems to form functionally equivalent transparently distributed systems is an important paradigm for constructing distributed systems. The extent to which such recursive transparency can be achieved depends crucially on the semantics and functionality offered by the underlying systems. It is therefore important that systems should be designed so that their functionality scales gracefully in a distributed environment.In order to build a transparent extension to a system, it is necessary to be able to intercept its basic operations and extend their meaning to a distributed environment. This requires the underlying system to have a clean structure with well-defined interfaces and the reflective capability necessary to intercept and extend operations crossing those interfaces. Thus, both reflection and transparency are important aspects of the design of extensible distributed systems.It is possible to make transparent extensions to object-oriented systems built on top of micro-kernel architectures but the lack of reflective capabilities in the current generation of object-oriented programming languages can make this unnecessarily awkward. More research is required to develop languages whose computational model and implementation are a better match for the underlying platforms which support them.
A performance study of the cancelback protocol for Time Warp
Authors: Samir R. Das, Richard M. Fujimoto
Venue: Proceedings of the seventh workshop on Parallel and distributed simulation (1993)

This work presents results from an experimental evaluation of the space-time tradeoffs in Time Warp augmented with the cancelback protocol for memory management. An implementation of the cancelback protocol on Time Warp is described that executes on a shared memory multiprocessor, a 32 processor Kendall Square Research Machine (KSR1). The implementation supports canceling back more than one object when memory has been exhausted. The limited memory performance of the system is evaluated for three different workloads with varying degrees of symmetry. These workloads provide interesting stress cases for evaluating limited memory behavior. We, however, make certain simplifying assumptions (e.g., uniform memory requirement by all the events in the system) to keep the experiments tractable. The experiments are extensively monitored to determine the extent to which various overheads affect performance. It is observed that (i) depending on the available memory and asymmetry in the workload, canceling back several (called the salvage parameter) events at one time may improve performance significantly, by reducing certain overheads, (ii) a performance nearly equivalent to that with unlimited memory can be achieved with only a modest amount of memory depending on the degree of asymmetry in the workload.
On bi-level conceptual schemas
Authors: Eugene Y. Sheng
Venue: Proceedings of the 1993 ACM conference on Computer science (1993)

The advent of Entity-Relationship (E-R) model has revolutionized the database design process. The overwhelming success of Entity-Relationship approach to database design partly lies in the simplicity and semantic clarity of the E-R model. However, two seemingly conflicting measurements of database design: logical-clarity and physical-efficiency, force database designers to choose either logically-clear design or physically-efficient design. As a result, the resulting design is either logically-clear or physically-efficient, but not both. This paper is to provide a remedy for this situation. In this paper, we first discuss the concept of logical-clarity and physical-efficiency of logical database design. Then the concept of bi-level conceptual schema is introduced. The bi-level conceptual schema concept allows us to create a logical database design that is both logically-clear and physically-efficient. Finally, a database management system prototype (DBMSB) that supports bi-level conceptual schema is described.
Parsing with C++ classes
Authors: Damian Conway
Venue: ACM SIGPLAN Notices (1994)

Philip W. Hall IV [1] has outlined a preprocessor technique for building recursive descent parsers using C++ constructor functions. This paper presents an alternative C++-based parser generation scheme which uses a hierarchy of classes with appropriately overloaded operators to embed the actual grammar of one or more parsers in a standard C++ source file. This approach eliminates the need for preprocessing of source files and permits the use of parsing schemes somewhat more sophisticated than simple statically-defined recursive descent.
Management of information technology innovation: a heuristic contingency paradigm research perspective
Authors: Mathew J. Klempa
Venue: Proceedings of the 1993 conference on Computer personnel research (1993)

This paper presents a contingency model which causally relates information technology acquisition and diffusion (IT/AD) to organization culture (heterogeneous versus homogeneous), organization learning (innovative versus adaptive), and knowledge sharing (networked versus hierarchical). The model integrates multiple and well-grounded theoretical streams of research. These three primary driving forces interact in a recursive dynamic, expressed in both rational driving forces and political driving forces. This paper focuses on the political driving forces, operationalizing them with five categories of measurement variables. A preliminary set of research propositions associated with the five categories of political driving forces are presented. Future research is suggested, addressing moderating variables, and information technology acquisition and diffusion patterns of S-curves.