ppxscal/embedding_network huggingface dataset:
Towards a Verified Abstract Machine for Logic Programming Language with a Notion of Scope
Authors: Keehang Kwon
Venue:  (1994)

This thesis concerns the design and verification of an abstract machine for the logic of hereditary Harrop formulas. This logic enlarges the traditional Horn clause logic by allowing implications and universal quantifiers in goals. While these symbols provide scoping constructs in logic programming, they raise new implementation problems: since universal and existential quantifiers may appear in mixed order in goals, the unification operation must be constrained to respect this ordering. Further, implication goals require new program clauses to be introduced dynamically and some reasonable method for maintaining programs is needed. A nondeterministic interpreter for the enriched logic that solves the first problem based on tagging constants and variables and using these tags in constraining unification has previously been described. We cast this description here into the evolving algebra formalism of Gurevich and refine it repeatedly to obtain an evolving algebra description that is transparently related to a reasonable abstract machine. The steps in this refinement process correspond to the introduction of environments as a prerequisite for sharing compiled code, an {\it implication} stack to permit the incremental addition and retraction of clauses from a program context, an {\it environment} stack for sharing goal sequences, the compilation of clause structure and of clause sequencing and, finally, a low level representation of terms and the compilation of unification. Our presentation covers various compilation techniques applicable to logic programming languages and also constitutes a verification of the final machine because each refinement step is accompanied by a proof that the essential notion of a computation ({\em i.e.}, answer substitution) is preserved by it. This thesis also considers the implementation of two further extensions to the language. The first of these corresponds to a mechanism for hiding the names of procedures. The second extension corresponds to the addition of a notion of modules. Using the original semantics for this notion leads to considerable redundancy in search. We refine the semantics to control this redundancy and then present an efficient scheme for implementing the resulting module construct.
DSL: A Wiley Tech Brief
Authors: Jennie Bourne, Dave Burstein
Venue:  (2002)

:Top-notch advice on adopting DSLDSL is exploding, with fifteen million fast Internet connections in 2001 and probably forty million more by 2003. The editors of DSL Prime, the weekly "industry bible," brief you on exactly what you need to know to put the technology to use. The book moves rapidly from the basics of the equipment through security, applications, and network management. With the authority of the industry's key periodical, Bourne and Burstein provide candid evaluations of the providers and manufacturers and offer technical managers a no-nonsense guide to make sound strategic decisions on DSL, reduce costs, and ensure a system that will run reliably and smoothly.Wiley Tech BriefsFocused on the needs of the corporate IT and business manager, the Tech Briefs series provides in-depth information on a new or emerging technology, solutions, and vendor offerings available in the marketplace. With their accessible approach, these books will help you get quickly up-to-speed on a topic so that you can effectively compete, grow, and better serve your customers.
Power series solutions for non-linear PDE's
Authors: F. Aroca, J. Cano, F. Jung
Venue: Proceedings of the 2003 international symposium on Symbolic and algebraic computation (2003)

This paper describes an algorithmic method iterative method for searching power series solutions of a partial differential equation. Power series expansions considered have support in some convex cone of RN. We do this by introducing a N-variables analog of the Newton polygon construction, used in the case of ordinary differential equations.
Concept of the Risk Evaluation Possibilities in Complex Systems
Authors: Yu. V. Esipov
Venue: Automation and Remote Control (2003)

For systems of the form &ldquo;potentially dangerous object&mdash;means and measures of protection&mdash;dangerous and harmful factors,&rdquo; consideration was given to the concept of multiple-parameter modeling and the possibilities of (fuzzy) risk evaluation which was intended for determining the asymptotic safety (risk) indices in the presence of fuzzy and/or incomplete source data about the system due to the cost or time constraints. This approach can be characterized as a fusion of the concepts of absolute safety and acceptable risk.
Discovering Spatial Locality in WWW Access Patterns using Data Mining of Document Clusters in Server Logs
Authors: Azer Bestavros
Venue:  (1997)

Abstract In this paper, we introduce the notion of a ``document cluster'''' in WWW space as a generalization of the notion of a ``cache line'''' in linear memory address space. Through the analysis of Web server logs, we show evidence of the spatial locality of reference in WWW access patterns and present an implementation of an efficient data mining algorithm that discovers document clusters. We show preliminary simulation results that quantify the benefits of using document clusters for file allocation on server disks, as well as for purposes of prefetching into server cache/main memory.
Properties of Lindenmayer fuzzy languages and /spl alpha/-driven Lindenmayer languages
Authors: E. M. zu Bexten, F. Sajadi, C. Moraga
Venue: Proceedings of the 27th International Symposium on Multiple-Valued Logic (1997)

This paper introduces Lindenmayer fuzzy languages and studies some of their properties. Lindenmayer languages are characterized by a parallel rewriting generation process. Lindenmayer fuzzy languages are characterized by expressiveness. Closure as well as a non-monotonic development aspects of these languages and their /spl alpha/-cut are discussed.
Design Considerations for Low Altitude Multiple Satellite (LAMS) DLC Protocols
Authors: C. Ward, C. H. Choi, T. Hain
Venue:  (1991)

This paper discusses design considerations for the LAMS-DLC protocol. Two important design issues of DLCPs that are intimately interrelated are reliability and performance. To design an efficient DLC protocol in a LAMS network, we note that a bounded inconsistency gap (Ig) and a bounded buffer are necessary conditions for continuous operation. Two time factors MSQT and MRHT are intimately associated with these two parameters and are the only necessary conditions required to bound them. Continuous operation can be achieved by a relaxation of the FIFO delivery constraint and bounding MSQT and MRHT. In this paper, we show that in LAMS-DLC, which relaxes the FIFO requirement, these two time factors are bounded in a reasonable time allowing continuous operation.
Elastic Vector Time
Authors: Christof FETZER, Michel Raynal
Venue: Proceedings of the 23rd International Conference on Distributed Computing Systems (2003)

In recent years there has been an increasing demand tobuild "soft" real-time applications on top of asynchronousdistributed systems. Designing and implementing such applicationsis a non-trivial task and applicationdesigners areoften faced with the need to circumvent impossibility results.In this paper we discuss how to ensure that actions are executedin the correct order even in the face of failures. Wepropose a novel time base and a new synchronization mechanismfor the design of distributed "soft" real-time applications.We demonstrate (1) how this time base can be usedto enforce an externally consistent ordering, and (2) howit permits to circumvent impossibility results by sketchinghow to solve the leader election and perfect failure detectionproblem.
Efficient resource utilization in shared-everything environments
Authors: Stefan Manegold, Johann K. Obermaier
Venue:  (1997)

Efficient resource usage is a key to achieve better performance in parallel database systems. Up to now, most research has focussed on balancing the load on several resources of the same type, i.e. balancing either CPU load or I/O load. In this paper, we present \emph{floating probe}, a strategy for parallel evaluation of pipelining segments in a shared-everything environment that provides dynamic load balancing between CPU- and I/O-resources. The key idea of floating probe is to overlap---as much as possible with respect to data dependencies---I/O-bound build phase and CPU-bound probe phase of pipelining segments to improve resource utilization. Simulation results show, that floating probe achieves shorter execution times while consuming less memory than conventional pipelining strategies.
Pre-fetching in File Systems for MIMD Multiprocessors
Authors: Schlatter C Ellis, David Kotz
Venue:  (1988)

The problem of providing file I/O to parallel programs has been largely neglected in the development of multiprocessor systems. There are two essential elements of any file system design intended for a highly parallel environment: parallel I/O and effective caching schemes. This paper concentrates on the second aspect of file system design and specifically, on the question of whether prefetching blocks of the file into the block cache can effectively reduce overall execution time of a parallel computation, even under favorable assumptions. Experiments have been conducted with an interleaved file system testbed on the Butterfly Plus multiprocessor. Some results of these experiments show that 1) the hit ratio, the accepted measure in traditional caching studies, is not an adequate measure of performance when the workload consists of parallel computations and parallel file access patterns, 2) caching with prefetching does significantly improve the hit ratio and the average time to perform an I/O operation, and 3) in spite of these gains, only weak improvement can be expected in overall execution time (an important negative result, given the optimistic nature of the study). We explore why is it not trivial to translate savings on individual I/O requests into much better overall performance and identify the key problems that need to be addressed in order to improve the potential of prefetching techniques in this environment.
State reduction in the exact analysis of fork/join queueing systems with homogeneous exponential servers
Authors: K. H. Yeung, T. S. Yum
Venue: Proceedings of the 1996 International Conference on Parallel and Distributed Systems (1996)

A state reduction technique for the exact analysis of fork/join queueing systems is presented in this paper. The technique is based on the standard Markov model and can be applied to systems having K homogeneous exponential servers. For a closed system with M jobs, the technique reduces the size of the state space from (M +1)K-MK states to ( M + K-1/ K - 1) states. This amounts to more than five orders of magnitude of state reduction for a typical value of K=M=10. The state reduction technique can also be applied to the analysis of an open fork/join queueing system. It reduces the size of the state space from (B+1)K states to (B + K/ K) states where B is the maximum number of jobs allowed in the open queueing system. The state reduction amounts to more than six orders of magnitude for a typical value of K=10 and B=500.KKK
Low-threat security patches and tools
Authors: M. A. Bashar, G. Krishnan, M. G. Kuhn, E. H. Spafford, S. S. Wagstaff,  Jr.
Venue: Proceedings of the International Conference on Software Maintenance (1997)

We consider the problem of distributing potentially dangerous information to a number of competing parties. As a prime example, we focus on the issue of distributing security patches to software. These patches implicitly contain vulnerability information that may be abused to jeopardize the security of other systems. When a vendor supplies a binary program patch, different users may receive it at different times. The differential application times of the patch create a window of vulnerability until all users have installed the patch. An abuser might analyze the binary patch before others install it. Armed with this information, he might be able to abuse another user's machine. A related situation occurs in the deployment of security tools. However, many tools will necessarily encode vulnerability information or explicit information about security "localisms". This information may be reverse-engineered and used against systems. We discuss several ways in which security patches and tools may be made safer. Among these are: customizing patches to apply to only one machine; disguising patches to hinder their interpretation; synchronizing patch distribution to shrink the window of vulnerability; applying patches automatically; and using cryptoprocessors with enciphered operating systems. We conclude with some observations on the utility and effectiveness of these methods.
Estimating the Parallel Performance of IQMR Method for Unsymmetric Large and Sparse Linear Systems
Authors: Laurence Tianruo Yang, Hai-xiang Lin
Venue: Proceedings of the Seventh International Conference on Parallel and Distributed Systems: Workshops (2000)

For the solutions of linear systems of equations with unsymmetric coefficient matrices, we have proposed an improved version of the quasi-minimal residual (IQMR) method [14] by using the Lanczos process as a major component combining elements of numerical stability and parallel algorithm design. The algorithm is derived such that all inner products and matrix-vector multiplications of a single iteration step are independent and communication time required for inner product can be overlapped efficiently with computation time. In this paper, we mainly present the qualitative analysis of the parallel performance with Store-and-Forward routing and Cut-Through routing schemes and topologies such as ring, mesh, hypercube and balanced binary tree. Theoretically, it is shown that the hypercube topology can give us the best parallel performance concerning parallel efficiency, speed-up, and runtime, respectively. We also study theoretical aspects of the overlapping effect in the algorithm. Some timing results are shown to verify the theoretical studies.
Highly Testable Boolean Ring Logic Circuits
Authors: Ugur Kalay, Douglas V. Hall, Marek A. Perkowski
Venue: Proceedings of the Twenty Ninth IEEE International Symposium on Multiple-Valued Logic (1999)

In this paper we show how Boolean Ring logic, a group-based logic, leads to a circuit implementation that is highly testable. We develop Boolean Ring based expressions, which we call Generalized-Literal Boolean-Ring Sum-of-Products (GL-BRSOP) and Universal-Literal Boolean-Ring Sum-of-Products (UL-BRSOP) to represent (powers of 2)-valued MVL functions. Our BRSOPs: allow MVL functions to be implemented with vectors of binary AND and EXOR gates; allow the use of a binary logic fault model; and allow a time-multiplexed implementation that is highly testable and uses less redundant circuitry.
Weighting Unusual Feature Types
Authors: Nicholas Howe, Claire Cardie
Venue:  (1999)

Feature weighting is known empirically to improve classification accuracy for k-nearest neighbor classifiers in tasks with irrelevant features. Many feature weighting algorithms are designed to work with symbolic features, or numeric features, or both, but cannot be applied to problems with features that do not fit these categories. This paper presents a new k-nearest neighbor feature weighting algorithm that works with any kind of feature for which a distance function can be defined. Applied to an image classification task with unusual set-like features, the technique improves classification accuracy significantly. In tests on standard data sets from the UCI repository, the technique yields improvements comparable to weighting features by information gain.
Quantitative Evaluation of Distributed Object-Oriented Programming Environments for Real-Time Applications
Authors: A. P. Flores, A. Nacul, L. Silva, J. Netto, C. E. Pereira, L. Bacellar
Venue: Proceedings of the 2nd IEEE International Symposium on Object-Oriented Real-Time Distributed Computing (1999)

This paper presents a quantitative evaluation of the temporal behavior of object-oriented programs implemented using different programming environments. The main focus of the evaluation is the real-time properties and the overhead caused by each layer of the underlying communication architecture, in order to verify the suitability of those environments for developing distributed real-time object-oriented systems. In the current state of the work, Java/RMI running over Windows 95 and AO/C++ running over QNX OS are compared. An extension of the comparison to include DCOM/Windows95, DCOM/Windows NT and ObjecTime/Windows NT is under development.
Optimization of GF(4) Expressions Using the Extended Dual Polarity Property
Authors: Dragan Jankovic, Radomir S. Stankovic, Claudio Moraga
Venue: Proceedings of the 33rd International Symposium on Multiple-Valued Logic (2003)

A method for optimization of Fixed Polarity Reed-Mullerexpressions (FPRM) using the dual polarityproperty has been presented in [7]. In [2], this methodhas been extended to optimization of Kroneckerexpressions by introducing the notion of extended dualpolarity property. In this paper, we propose ageneralization of this method to optimization of Fixedpolarity Galois field (GF) expressions for quaternaryfunctions. The proposed method exploits a simplerelationship between fixed polarity GF expressions fordual polarities.
Regression Testing on Object-Oriented Programs
Authors: Ye Wu, Mei-Hwa Chen, Howard M. Kao
Venue: Proceedings of the 10th International Symposium on Software Reliability Engineering (1999)

Regression testing is an important activity at both testing and maintenance phases. When a piece of software is modified, it is necessary to ensure the quality of the software is preserved. To this end, regression testing is to retest the software using the test cases selected from the original test pool. In this paper, we present a regression testing technique that selects test cases by utilizing static information from the analysis of the program structure and dynamic information by tracing the function-calling sequences. To com-pare the effectiveness of this technique with other existing approaches, we conducted an empirical study on an industrial real-time system. The results show that not only does this technique preserve all the necessary information for regression testing, but it is also much more efficient and more precise than the existing techniques.
Scientific approaches and techniques for negotiation. A game theoretic and artificial intelligence perspective
Authors: Enrico H. Gerding, David D.B. Bragt, J. A. L Poutre
Venue:  (2000)

Due to the rapid growth of electronic environments (such as the Internet) much research is currently being performed on autonomous trading mechanisms. This report contains an overview of the current literature on negotiations in the fields of game theory and artificial intelligence (AI). Game theorists have successfully developed and analyzed a variety of bargaining models in the past decades. We give an extensive overview of this theoretical work. In particular, research performed in the fields of cooperative and non-cooperative bargaining, bargaining with incomplete information, and bargaining over multiple issues is evaluated. The use and shortcomings of game-theoretical concepts in practical applications is discussed. Simplifying assumptions frequently made in game-theoretical analyses, such as assumptions of perfect rationality and common knowledge, do not need to be made if the behavior of boundedly-rational negotiating agents is modeled directly, for instance using techniques borrowed from the field of AI. We show how different AI-techniques, such as decision trees, Q-learning, evolutionary algorithms, and Bayesian beliefs, can be used to develop a negotiation environment consisting of intelligent agents. These agents are able to adapt their negotiation strategies to changing user preferences and opponents. A survey of state-of-the art applications using AI-techniques is given in this report. The main conclusion from this survey is that combining techniques and ideas from game theory and AI will make it possible to create robust and intelligent negotiation systems in the near future.
Development of the Computer Assisted Circuit Editing System (CACES)
Authors: David B. Lambert
Venue:  (1994)

For many years, educators have been trying to incorporate computers into the education system. This has often been hampered by the lack of design tools to help build quality instruction systems. The Computer Aided Circuit Editing System (CACES) has been developed to help build representations of simple electronic circuits for use within an intelligent tutoring system. CACES allows the user to build a representation of an electrical circuit without knowledge of computer programming. Such tools will be essential if tutoring systems are to gain widespread acceptance in education.
Certitude and Rectitude
Authors: Peter G. Neumann
Venue: Proceedings of the 4th International Conference on Requirements Engineering (ICRE'00) (2000)

Certitude: the state of being or feeling certain; Rectitude: correctness of judgment or procedure. There is a fundamental difference between certification (which is intended to give you the feeling that someone or something is doing the right thing) and correctness (for which you hopefully have some well-founded reason to believe that someone or something is doing the right thing - with respect to appropriate definitions of what is right). Certification is typically nowhere near enough; correctness is somewhat closer to what is needed, although often unattainable in the large - that is, with respect to the entire system. However, formal demonstrations that something is correct are potentially much more valuable than loosely based certification. Therefore, a challenge confronting us here is to endow certification - of people and of systems - with a greater sense of rigor and credibility.
Notes on Proof Outline Logic
Authors: Fred B. Schneider
Venue:  (1995)

Formulas of Proof Outline Logic are program texts annotated with assertions. Assertions may contain control predicates as well as terms whose values depend on previous states, making the assertion language rather expressive. The logic is complete for proving safety properties of concurrent programs. A deductive system for the logic is presented. Solutions to the mutual exclusion and readers/writers problems illustrate how the logic can be used as a tool for program development.
A Reference Model for Requirements and Specifications
Authors: Carl A. Gunter, Elsa L. Gunter, Michael Jackson, Pamela Zave
Venue: Proceedings of the 4th International Conference on Requirements Engineering (ICRE'00) (2000)

We define a reference model for applying formal methods to the development of user requirements and their reduction to behavioral specification of a system. The approach is characterized by its focus on the shared phenomena that define the interface between the system and the environment in which it will operate and on how the parts of this interface are controlled. This paper extends our previous work on this model by representing it in higher-order logic and determining some of its key mathematical ramifications. In particular, we introduce a new form of refinement, which is pivotal to defining the desired soundness and consistency properties precisely.