ppxscal/embedding_network huggingface dataset:
An Efficient Existentially Unforgeable signature Scheme and its Applications
Authors: C. Dwork, M. Naor
Venue:  (1995)

A signature scheme is existentially unforgeable if, given any polynomial (in the security parameter) number of pairs (m>sub<1>/sub<, S(m>sub<1>/sub<)), (m>sub<2>/sub<, S(m>sub<2>/sub<)), ... (m>sub<k>/sub<, S(m>sub<k>/sub<)) where S(m) denotes the signature on the message m, it is computationally infeasible to generate a pair (m>sub<k+1>/sub<, S(m>sub<k+1>/sub<)) for any message m>sub<k+1>/sub< I {m>sub<1>/sub<, ... m>sub<k>/sub< }. We present an existentially unforgeable signature scheme that requires at most 6 times the amount of time needed to generate a signature using RSA (which is not existentially unforgeable), and point out applications where its use is desirable.
ASTRAL Software Development Environment User''s Manual
Authors: Paul Z. Kolano
Venue:  (1997)

ASTRAL is a formal specification language for real-time systems. It is intended to support formal software development and, therefore, has been formally defined. The structuring mechanisms in ASTRAL allow one to build modularized specifications of complex systems with layering. A real-time system is modeled by a collection of state machine specifications and a single global specification. The ASTRAL software development environment is an integrated set of design and analysis tools based on the ASTRAL formal framework. The tools that make up the support environment are a syntax-directed editor, a specification processor, a verification condition generator, and a browser kit. This document describes the features and use of the ASTRAL software development environment.
Implementing Operating Systems without Kernels
Authors: Dave Probert, John Bruno
Venue:  (1996)

Most contemporary operating systems are structured around a central monolithic kernel (or micro-kernel). An alternative is to construct operating systems without a kernel. In this approach, operating system abstractions (processes, threads, virtual memory, communication) are implemented as application-level code, with the attendant flexibility and extensibility that many user applications require. We are building such a kernel-less operating system, using optimized cross-domain calls which can reduce cross-domain invocations cost below the current cost of kernel invocations by exploiting properties that kernel-less operating systems have with respect to robustness, extensibility, security, and performance. The first three of these properties are generally accepted as benefits of the kernel-less approach. One of the primary contributions of this work is to achieve these benefits while also achieving gains in performance.
Extending Applications to the Network
Authors: Marwood David, David Marwood
Venue:  (1998)

Network applications are applications capable of selecting, at run-time, portions of their code to execute at remote network locations. By executing remote code in a restricted environment and providing convenient communication mechanisms within the application, network applications enable the implementation of tasks that cannot be implemented using traditional techniques. Even existing applications can realize significant performance improvements and reduced resource consumption when redesigned as network applications. By examining several application domains, we expose specific desirable capabilities of a software infrastructure to support network applications. These capabilities entail a variety of interacting software development challenges for which we recommend solutions. The solutions are applied in the design and implementation of a network application infrastructure, Jay, based on the Java language. Jay meets most of the desired capabilities, particularly demonstrating a cohesive and expressive communication framework and an integrated yet simple security model. In all, network applications combine the best qualities of intelligent networks, active networks, and mobile agents into a single framework to provide a unique and effective development environment.
Dynamic Character Recognition Using Hidden Markov Models
Authors: Matthew S. Ryan, Graham R. Nudd
Venue:  (1993)

Hidden Markov Model theory is an extension of the Markov Model process. It has found uses in such areas as speech recognition, target tracking and word recognition. One area which has received little in the way of research interest, is the use of Hidden Markov Models in character recognition. In this paper the application of Hidden Markov Model theory to dynamic character recognition is investigated. The basic Hidden Markov Model theory is reviewed, and so are the algorithms associated with it. A quick overview of the dynamic character recognition process is considered. Then three types of describing characters are considered, position, inclination angle of small vectors and stroke directional encoding using a Freeman code. A system using each of these descriptions, using Hidden Markov Models in the comparison stage, is described. It is recognised that experiments using the different encoding systems have to be carried out to check the validity of this chosen method.
The Utility of Exploiting Idle Memory for Data-Intensive Computations
Authors: Anurag Acharya, Sanjeev Setia
Venue:  (1998)

In this paper, we examine the utility of exploiting idle memory in workstation pools. We attempt to answer the following questions. First, given a workstation pool, what fraction of the memory can be expected to be idle? This provides an estimate of the opportunity for hosting guest data. Second, what fraction of a individual host''s memory can be expected to be idle? This helps determine the recruitment policy -- what is the maximum amount of memory that should be recruited on a single host? Third, what is the distribution of memory idle-times? That is, what is the probability that a chunk of memory that is currently idle will be idle for longer than time t? This information indicates how long guest data can be expected to survive; applications that access their data-sets frequently within the expected life-time of guest data are more likely to benefit from exploiting idle memory. Fourth, how much benefit can a user expect? We use two metrics for the benefit of exploiting idle memory: (1) if I have a pool with w workstations, how much memory should I expect to get for free by harvesting idle memory; (2) how much improvement can be achieved in end-to-end execution time? Finally, how long and how frequently might a user have to wait to reclaim her machine if she volunteers to host guest pages on her machine? This helps answer the question of social acceptability. To answer the questions relating to the availability of idle memory, we have analyzed two-week long traces from five workstation pools with different sizes, locations, and patterns of use. To evaluate the expected benefits and costs, we have simulated three data-intensive applications (0.5GB-5GB) on these workstation pools.
Parallel and Distributed Algorithms for Constraint Networks"
Authors: Ying Zhang, Alan K. Mackworth
Venue:  (1991)

This paper develops two new algorithms for solving a finite constraint satisfaction problem (FCSP) in parallel. In particular, we give a parallel algorithm for the EREW PRAM model and a distributed algorithm for networks of interconnected processors. Both of these algorithms are derived from arc consistency algorithms which are preprocessing algorithms in general, but can be used to solve an FCSP when it is represented by an acyclic constraint network. If an FCSP can be represented by an acyclic constraint network of size \fIn\fP with width bounded by a constant then (1) the parallel algorithm takes \fIO(log n)\fP time using \fIO(n)\fP processors and (2) there is a mapping of this problem to a distributed computing network of \fIpoly(n)\fP processors which stabilizes in \fIO(log n)\fP time.
The Iterative Data Cube
Authors: M. Riedewald, D. Agrawal, A. E Abbadi
Venue:  (2000)

Data cubes provide aggregate information to support the analysis of the contents of data warehouses and databases. An important tool to analyze data in data cubes is the range query. For range queries that summarize large regions of massive data cubes, computing the query result on-the-fly can result in non-interactive response times (e.g. in the order of minutes). To speed up range queries, values that summarize regions of the data cube are pre-computed and stored. This faster response time results in more expensive updates and/or space overhead. In this paper a technique is presented that generates a new class of schemes that support range queries on data cubes -- Iterative Data Cubes. The main idea is that techniques that provide a certain tradeoff of query and update costs for a one-dimensional data cube are applied iteratively along the dimensions of data cubes of higher dimensionality. The different one-dimensional techniques can be combined, resulting in a great variety of Iterative Data Cubes. We show that Iterative Data Cubes are easy to generate, analyze and implement. They generalize previous seemingly unrelated approaches. Our technique is applicable to aggregate operators and attributes if the attribute''s domain forms an abelian group under the aggregate operator (e.g., integers under addition). In this paper we focus on techniques that do not cause any space overhead for dense data cubes.
Generating Low-Degree 2-Spanners
Authors: G. Kortsarz, D. Peleg
Venue:  (1993)

A k-spanner of a connected graph G = (V,E) is a subgraph G\spr consisting of all the vertices of V and a subset of the edges, with the additional property that the distance between any two vertices in G\spr is larger than that distance in G by no more than a factor of k. This paper concerns the problem of finding a 2-spanner in a given graph, with minimum maximum degree. A randomized approximation algorithm is provided for this problem, with approximation ration of [O\tilde](D1/4).
J-Inner Matrix Functions, Interpolation and Inverse Problems for Canonical Systems, I: Foundations
Authors: D. Z. Arov, H. Dym
Venue:  (1998)

This is the first of a planned sequence of papers on inverse problems for canonical systems of differential equations. It is devoted largely to foundational material (much of which is of independent interest) on the theory of assorted classes of meromorphic matrix valued functions. Particular attention is paid to the structure of J-inner functions and connections with bitangential interpolation problems and reproducing kernel Hilbert spaces. Some new characterizations of regular, singular and strongly regular J-inner functions in terms of the associated reproducing kernel Hilbert spaces are presented.
Wing Design for a High-Speed Civil Transport Using a Design of Experiments Methodology
Authors: Giunta Anthony A., Balabanov Vladimir, Haim Dan, Grossman Bernard, Mason William H., Watson Layne T., Haftka Raphael T.
Venue:  (1996)

The presence of numerical noise inhibits gradient-based optimization and therefore limits the practicality of performing aircraft multidisciplinary design optimization (MDO). To address this issue, a procedure has been developed to create noise free algebraic models of subsonic and supersonic aerodynamic performance for use in the MDO of high-speed civil transport (HSCT) configurations. This procedure employs methods from statistical design of experiments theory to select a set of HSCT wing designs (fuselage/tail/engine geometry fixed) for which numerous detailed aerodynamic analyses are performed. Polynomial approximations (i.e., response surface models) are created from the aerodynamic data to provide analytical models relating aerodynamic quantities (e.g., wave drag and drag-due-to-lift) to the variables which define the HSCT wing configuration. A multidisciplinary design optimization of the HSCT is then performed using the response surface models in lieu of the traditional, local gradient based design methods. The use of response surface models makes possible the efficient and robust application of MDO to the design of an aircraft system. Results obtained from five variable and ten variable wing design problems presented here demonstrate the effectiveness of this response surface modeling method.
A review of procedures used for the correction of seismic data
Authors: N. A. Alexander, A. A. Chanerley, N. Goorvadoo
Venue: Proceedings of the eighth international conference on The application of artificial intelligence to civil and structural engineering computing (2001)

This paper reviews some of the existing procedures used in the correction of seismic data. It concludes that a general lack of information on the correction processes used, with notable exceptions, when supplying CD-corrected data makes it difficult to draw conclusions on the reliability of the corrected data records. Of particular concern has been the possible corruption of phase data. The paper traces the development of the correction procedures and describes their rationale and methodology. The paper proposes modifications to the existing procedures and provides a software listing used in this study as a step in the interests of good practise in disseminating information on seismic correction. Moreover the paper proposes several metrics for judging the reliability of corrected data through the use of power spectral densities, phase spectra, coherence estimates, acceleration response spectra and the short-time Fourier transform and draws conclusions on the reliability of some of the correction procedures used.
A review of the self-designing structures approach on the optimisation of engineering structures
Authors: J. W. Bull, Z. Pitouras
Venue: Proceedings of the eighth international conference on The application of artificial intelligence to civil and structural engineering computing (2001)

The research program entitled 'Self-Designing Structures' developed two and three-dimensional topological optimisation computer programs, based on the iterative use of finite elements. Where the stresses were high, material was added. Where the stresses were low, material was taken away. This paper presents an outline of the EMERGE program, the Element Removal and Accretion algorithm and the Evolutionary Material Translation algorithm. Three problems were solved using the Self-Designing Structures optimisation method.
Measurement and Evaluation of Complex Navy Systems Designs
Authors: Osman Balci, David DeVaux, Richard E. Nance
Venue:  (1993)

The purpose of this paper is to present a multifaceted approach to the measurement and evaluation of complex Navy system designs with embedded realtime mission critical characteristics. The approach advocates the use of a visual simulation model, constructed in the Visual Simulation Support Environment (VSSE), representing the design so as to achieve dynamic measurement of the design. A knowledge-based approach is proposed for the independent evaluation of hundreds of design indicators. The Objectives/Principles/Attributes (OPA) framework is used as the underlying structure for the measurement and evluation of all three major aspects of a system design: project, process, and product.
Spline Overlay Surfaces
Authors: Richard H. Bartels, David R. Forsey
Venue:  (1993)

We consider the construction of spline features on spline surfaces. The approach taken is a generalization of the hierarchical surface introduced in [Forsey88]. Features are regarded as spline-defined vector displacement fields that are overlain on existing surfaces. No assumption is made that the overlays are derived from the base surface. They may be applied with any orientation in a non-hierarchical fashion. In particular, we present a ``cheap'''' version of the concept in which the displacement field is mapped to the base surface approximately, through the mapping of its control vectors alone. The result is a feature that occupies the appropriate position in space with respect to the base surface. It may be manipulated and rendered as an independent spline, thus avoiding the costs of a true displacement mapping. This approach is useful for prototyping and previewing during design. When a finished product is desired, of course, true displacement mapping is employed.
Interleaved Contractions
Authors: W. van der Hoek, M. de Rijke
Venue:  (1996)

We study an approach to concurrent contractions, that is, to simultaneous contractions performed by multiple agents. Using ideas from the semantics of programming we adopt an interleaved approach to reason about concurrent contractions. Although many of the notions from the traditional Gaerdenfors approach transfer to this setting, our approach also forces us to depart from the Gaerdenfors framework in important ways. We present laws describing rational concurrent contractions, as well as a construction that satisfies these laws.
ADAPTIVE-PREDICTIVE GAME-PLAYING PROGRAMS
Authors: Robert Levinson, Brian Beach, Tal Dayan, Richard Snyder, Kirack Sohn
Venue:  (1990)

Adaptive-predictive search (APS) is a new method by which systems can improve their search performance through experience. It is believed that the development of such methods is critical as currently a tremendous amount of computational results are potentially wasted by not integrating search and partial search results into the knowledge of a problem-solving system. In the adaptive-predictive search model pattern formation and associative recall are used to improve or replace search. In this paper the theory, background and motivations behind the model are presented and its application to two-player game-playing programs is discussed. In these programs, the system develops a knowledge base of patterns (boolean features) coupled with weights and using pattern-oriented evaluation performs only 1-ply search, yet competes respectably with programs that search more. The learning mechanism is a hybridization of machine learning and artificial intelligence techniques that have been successful in other settings. Specific examples and performance results are taken from the domains of Hexapawn, Tic-Tac-Toe, Pente, Othello, and Chess. [This report is much like 89-22, but focuses on 2-player games and gives new results.]
A Methodology for Deductive Verification of Out-of-Order Execution Systems Based on Predicted Values,
Authors: T. Arons, A. Pnueli
Venue:  (2001)

In this paper we propose a methodology for the deductive verification of out-of-order scheduling algorithms. A `top-down'' scheme for the systematic definition of system invariants is defined. The complementary use of predicted values, auxiliary fields storing a dispatch time prediction of an instruction''s value, is proposed as a means of further simplifying the verification of systems in this class. We illustrate the use of the `top-down'' methodology and predicted values in the verification of three out-of-order scheduling algorithms, including a detailed discussion of the verification of a model based on the Mips R10000.
Evaluation of Dynamic Access Ordering Hardware
Authors: S. A. McKee, C. W. Oliver, Wm Wulf, K. L. Wright, J. H. Aylor
Venue:  (1995)

Memory bandwidth is rapidly becoming the limiting performance factor for many applica- tions, particularly for streaming computations - such as scientific vector processing or mul- timedia (de)compression - that lack the locality of reference that makes caching effective. We describe and evaluate a system that addresses the memory bandwidth problem for this class of computations by dynamically reordering stream accesses to exploit memory system architecture and device features. The technique is practical to implement, using existing compiler technology and requiring only a modest amount of special-purpose hardware. With our prototype system, we have observed performance improvements by over 200% over normal caching.
Hopfield Nets - More Formally
Authors: Nandit Soparkar, Avi Silberschatz
Venue:  (1992)

Hopfield nets are a class of Neural networks that are often applied to optimization problems. The role played by certain constants appearing in the interconnections are crucial to the computations. A bad choice of constant values results in the convergence of the system to states that represent extraneous results. This paper examines a discrete model of the nets which allows a better characterization of the constants. The formal approach followed in this paper allows the specification of values to the constants that ensure convergence of the system to states that represent results that are not extraneous. Using the Hopfield nets terminology, we have identified methods to remove extraneous energy minima in the discrete version of the system. Since any simulation study of Hopfield nets on real computers must use discretized approximations to analog values, the results are of interest in a practical domain as well.
Task-Oriented Representation of Asynchronous Interfaces
Authors: Antonio C. Siochi, H. R Hartson
Venue:  (1988)

A simple, task-oriented notation for describing user actions in asynchronous user interfaces is introduced. This User Action Notation (UAN) allows the easy association of actions with feedback and system state changes as part of a set of asynchronous interface design techniques, by avoiding the verbosity and potential vagueness of prose. Use within an actual design and implementation project showed the UAN to be expressive, concise, and highly readable because of its simplicity. The task-and user-oriented techniques are naturally asynchronous and a good match for object-oriented implementation. Levels of abstraction are readily applied to allow definition of primitive tasks for sharing and reusability and to allow hiding of details for chunking. The UAN provides a critical articulation point, bridging the gap between the task viewpoint of the behavioral domain and the event-driven nature of the object-oriented implementational domain. The potential for UAN task description analysis may address some of the difficulties in developing asynchronous interfaces.
Dynamic Access Ordering: Bounds on Memory Bandwidth
Authors: Sally A. McKee
Venue:  (1994)

Memory bandwidth is becoming the limiting performance factor for many applications, particu- larly scientific computations. Access ordering is one technique that can help bridge the processor- memory performance gap. We are part of a team developing a combined hardware/software scheme for implementing access ordering dynamically at run-time. The hardware part of this solution is the Stream Memory Controller, or SMC. In order to validate the SMC concept, we have conducted numerous simulation experiments, the results of which are presented elsewhere. We have developed analytical models to bound asymptotic uniprocessor SMC performance, and have demonstrated that the simulation behavior of our dynamic access-ordering heuristics approaches those bounds. Here we introduce a model of of SMC startup costs, and we extend the uniprocessor SMC models to describe performance for modest-sized symmetric multiprocessor (SMP) SMC systems.
Analyzing Partially-Implemented Real-Time Systems
Authors: George S. Avrunin, James C. Corbett, Laura K. Dillon
Venue:  (1996)

We propose a method for analyzing partially-implemented real-time systems. Here we consider real-time concurrent systems for which some components are implemented in Ada and some are partially specified using regular expressions and Graphical Interval Logic (GIL), a real-time temporal logic. We show how to construct models of the partially-implemented systems that account for such properties as run-time overhead and scheduling of processes, yet support tractable analysis of nontrivial programs. The approach can be fully automated, and we illustrate it by analyzing a small example.