ppxscal/embedding_network huggingface dataset:
Error reduction by parallel repetition-the state of the art
Authors: U. Feige
Venue:  (1995)

We show that no fixed number of parallel repetitions suffices in order to reduce the error in two-prover one-round proof systems from one constant to another. Our results imply that the recent bounds proven by Ran Raz, showing that the number of rounds that suffice is inversely proportional to the answer length, are nearly best possible. Our proof technique builds upon an idea of Oleg Verbitsky. We use this opportunity to survey the known results on parallel repetition, and to present the proofs of some previously claimed theorems.
A Framework for the Study of Query Decomposition for Heterogeneous Distributed Database Management Systems
Authors: Konstantinos Triantis, Csaba J. Egyhazy
Venue:  (1987)

This paper presents a framework for the study of the query decomposition translation for heterogeneous record -oriented database management systems. This framework is based on the applied database logic representation of relational, hierarchical and network databases. The input to the query decomposition translation is the query graph which is derived from the complex to basic, external to conceptual and logical optimization translations. Once the query graph is obtained the objective of the query decomposition translation is to break up a query expressed in terms of the actual or conceptual databases into its component parts or subqueries and find a strategy indicating the sequence of primitive or fundamental operations and their corresponding processing sites in the network necessary to answer the query. The query processing strategy is usually chosen so as to satisfy some performance criterion such as response time reduction. Contingent on after each primitive operation. The prequery decomposition translation, the query decomposition translation and the size estimation issues are presented through an example based on the current implementation of the Distributed Access View Integration Database (DAVID) currently being built at NASA''s Goddard Space Flight Center (GSFC). The choice of a query processing strategy is the successful estimation of intermediate results
Avoiding Irreproducible Results: Modeling the Stream Memory Controller
Authors: S. A. McKee, D. A. B. Weikle, K. L. Wright, C. W. Oliver, T. C. Landon, A. P. Voss, Wm Wulf, J. H. Aylor
Venue:  (1995)

Recent discussions have acknowledged the danger of the Computer Architecture community becoming a "society for irreproducible results". Unfortunately, there is little incentive within our community to verify others'' results. We have a tendency to experiment with a single instance of an artifact, but then to generalize about the properties of all related artifacts. A third consideration is that there is an inherent artificiality to our work that makes it even more difficult not to build our own assumptions into the structure of our experiments. We create the artifacts being studied in addition to the instruments and experiments used to study them. Finally, reproducing results usu- ally requires reproducing the experimental environment as well, which is often difficult. We describe the research strategy we used to avoid these pitfalls when trying to demonstrate the effectiveness of a particular concept: dynamic access ordering. We present this case study to demonstrate that our results are reproducible several different ways, and to convey our experi- ences in hopes that a similar approach might prove useful to others.
Subsequence and Run Heuristics for Sorting by Transpositions
Authors: Guyer Scott A., Heath Lenwood S., Vergara John Paul C.
Venue:  (1997)

Sorting by tranpositions is the problem of finding the minimum number of transpositions required to sort a permutation pi. A transposition involves repositioning a contiguous sequence (block) of elements by inserting it elsewhere in the permutation. The problem has applications in the study of genome rearrangements and phylogeny reconstruction. In this paper, several heuristics based on analyses of subsequences and runs in a permutation are employed. Experimental results are provided. The algorithm based on the longest increasing subsequence in a permutation appears most promising.
ON THE INVARIANCE OF MEASURED EQUATION OF INVARIANCE
Authors: Wei Hong, Weikai Sun, Wayne W Dai
Venue:  (1995)

The key to the method of measured equation of invariance (MEI) is the Postulate: ``the MEI is independent of the excitation''''. The word ``postulate'''' certainly just means a guess without rigorous proof. In The report, we theoretically prove that the MEI is independent of the Excitation on the restriction of O(h^2), here h is the discretization step. The error between the accurate solution and the solution of the MEI is shown. Besides, we show that the ``metrons'''' are indeed not basis functions with substantial illustrations.
Facilitating Hard Active Database Applications
Authors: Lane B Warshaw
Venue:  (2001)

Active database technology enhances traditional databases with rules that are executed in response to database events. Tills enhancement promises exceptional returns. Useful applications of the technology include view maintenance, workflow, and real-time decision control systems. Unfortunately, penetration of active databases has largely been restricted to simple rule systems. This narrowed focus can be attributed to all explicit connection of the active rules to the underlying concurrency control system. Although tills explicit Connection provides a level of flexibility, it becomes semantically intractable in more complex applications. Furthermore, rule execution is computationally intensive. Since rules spawn the execution of many queries over the contents of the database. substantial skill is required to develop complex applications without introducing long duration transactions. This dissertation addresses three issues surrounding application development that inhibits the feasibility of active databases. First, a quantitative evaluation is performed on the semantics of VenusDB, a modular active database Ianguage that executes within the nested transaction model. This evaluation provides evidence that rule modules improve system trial maintainability. Second, the most general contribution of this dissertation is the identification and study of Log Monitoring Applications (LMAs). LMAs are expert system applications that analyze logs maintained in a database. This dissertation develops the formal execution semantics and correctness proofs of concurrency schemes for applications within the LMA class. The results show that only a minimal number of coupling modes are necessary for the database integration of hard rule systems obeying the LMA restrictions. Third, the architecture and evaluation of an active database optimizer is presented. This optimizer uses database statistics to optimize rules as well as suggest physical schema optimizations. The optimizer is integrated within VenueDB to improve system scalability.
Parallel Refinement Mechanisms
Authors: Paul Z. Kolano
Venue:  (1999)

Refinement is a fundamental design technique that has often challenged the "formal methods" community. In most cases, mathematical elegance and proof manageability have been chosen over flexibility and freedom, which are often needed in practice to deal with unexpected or critical situations. The issue of refinement becomes even more critical when dealing with real-time systems where timing analysis is a crucial factor. In this case, the literature exhibits only a few, fairly limited proposals. In this paper, we propose general refinement mechanisms for real-time systems that allow several types of implementation strategies to be specified in a fairly natural way. Not surprisingly, generality has a price in terms of complexity. In our approach, however, this price is paid only when necessary. Furthermore, the proof system is amenable both for traditional hand-proofs, based on human ingenuity and only partially formalized, and for fully formalized, tool-supported proofs.
Parallel Combinator Reduction: Some Performance Bounds
Authors: M. S. Joy, T. H. Axford
Venue:  (1992)

A parallel graph reduction machine simulator is described. This performs combinator reduction and can simulate various different parallel reduction strategies. A number of functional programs are examined, and experimental results presented comparing the amount of parallelism obtainable using explicit divide-and-conquer with the maximum amount of parallelism available in the programs.
A new beam finite element for tapered members
Authors: N. Boissonnade, J. P. Muzeau
Venue: Proceedings of the eighth international conference on The application of artificial intelligence to civil and structural engineering computing (2001)

This paper presents a new analytical formulation for the analysis of tapered thin-walled beams. A new expression of the non linear axial strain for tapered beams is first proposed; it is then used to derive the general equilibrium equations. These last are detailed in the case of linear elasticity and tapered monosymmetric I-beams. Particular attention is paid to lateral-torsional buckling, including initial bending curvature. Accordingly, a new beam finite element has been carried out and implemented in a FEM software. Several examples of stability analysis are given, showing that classical prismatic elements can provide erroneous results when used to simulate the behaviour of tapered members.
Separation Constraint Partitioning - A New Algorithm for Partitioning Non-strict Programs into Sequential Threads
Authors: Klaus E. Schauser, David E. Culler, Seth C. Goldstein
Venue:  (1995)

In this paper we present substantially improved thread partitioning algorithms for modern implicitly parallel languages. We present a new block partitioning algorithm, separation constraint partitioning, which is both more powerful and more flexible than previous algorithms. Our algorithm is guaranteed to derive maximal threads. We present a theoretical framework for proving the correctness of our partitioning approach, and we show how separation constraint partitioning makes interprocedural partitioning viable. We have implemented the partitioning algorithms in an Id90 compiler for workstations and parallel machines. Using this experimental platform, we quantify the effectiveness of different partitioning schemes on whole applications.
Semantic Locking in Object-Oriented Database Systems
Authors: Rodolfo F. Resende, Divyakant Agrawal, Amr El Abbadi
Venue:  (1994)

Object-oriented databases are being increasingly used to model non-standard applications that emphasize modularity, composition, and rapid prototyping. Semantic locking protocols are presented for transaction management for such object-oriented databases. In particular, the protocol incorporates the semantics of complex objects, nested executions and dynamic conflicts resulting from referentially shared objects.
Topological optimization of an aircraft engine mount via bit-masking oriented genetic algorithms
Authors: L. Iuspa, F. Scaramuzzino, P. Petrenga
Venue: Proceedings of the eighth international conference on The application of artificial intelligence to civil and structural engineering computing (2001)

In the present paper a geometric-topologic structural optimisation procedure of a transport aircraft engine mount is shown. In order to achieve the minimum structural weight under some functional and operative constraints, both static and dynamic aspects have been treated. A parametric FEM model with extended self-consistent topology controls has been developed. The genetic algorithm used for the optimisation procedure was based on a specific bit-masking oriented data structure able to properly handle both continuous and discrete design variables requested by the hybrid geometric-topological model of structure.
A NEW DATA STRUCTURE FOR CUMULATIVE PROBABILITY TABLES: AN IMPROVED FREQUENCY-TO-SYMBOL ALGORITHM
Authors: Peter M. Fenwick
Venue:  (1995)

A recent paper presented a new efficient data structure, the ``Binary Indexed Tree'''', for maintaining the cumulative frequencies for arithmetic data compression. While algorithms were presented for all of the necessary operations, significant problems remained with the method for determining the symbol corresponding to a known frequency. This report corrects that deficiency. This report is being filed also with the Department of Computer Science, The University of Auckland, as Technical Report 110, ISSN 1173-3500.
A Method for Extracting the Spectral Envelope
Authors: Yoshihisa Ishida
Venue:  (1991)

This paper considers a method for spectral envelope extraction. The spectral envelope estimated by this method has no effect on the spectral fine structure and it is more stable with respect to time than that estimated by the conventional FFT method.
DIRICHLET MIXTURES: A METHOD FOR IMPROVING DETECTION OF WEAK BUT SIGNIFICANT PROTEIN SEQUENCE HOMOLOGY
Authors: Kimmen Sjolander, Kevin Karplus, Michael Brown, Richard Hughey, Anders Krogh, I. S Mian, David Haussler
Venue:  (1996)

This paper presents the mathematical foundations of Dirichlet mixtures, which have been used to improve database search results for homologous sequences, when a variable number of sequences from a protein family or domain are known. We present a method for condensing the information in a protein database into a mixture of Dirichlet densities. These mixtures are designed to be combined with observed amino acid frequencies, to form estimates of expected amino acid probabilities at each position in a profile, hidden Markov model, or other statistical model. These estimates give a statistical model greater generalization capacity, such that remotely related family members can be more reliably recognized by the model. Dirichlet mixtures have been shown to outperform substitution matrices and other methods for computing these expected amino acid distributions in database search, resulting in fewer false positives and false negatives for the families tested. This paper corrects a previously published formula for estimating these expected probabilities, and contains complete derivations of the Dirichlet mixture formulas, methods for optimizing the mixtures to match particular databases, and suggestions for efficient implementation.
"Pluggable" user models for adaptive hypermedia in education
Authors: M. R. Zakaria, A. Moore, C. D. Stewart, T. J. Brailsford
Venue: Proceedings of the fourteenth ACM conference on Hypertext and hypermedia (2003)

Most adaptive hypermedia systems used in education implement a single user model - inevitably originally designed for a specific set of circumstances. In this paper we describe an architecture that makes use of XML pipelines to facilitate the implementation of different user models.
Marginal Cost-Benefit Analysis for Predictive File Prefetching
Authors: Timothy Highley, Paul Reynolds
Venue:  (2003)

File prefetching can reduce file access latencies and improve overall performance. Prefetching can be especially important in on-line software on demand, where network latencies create unacceptable delays. Prefetching involves predicting future accesses and establishing when/whether to prefetch, based on future access predictions. Cost-benefit analysis (CBA) addresses when/whether to prefetch and it addresses the interaction between prefetching and caching. CBA weighs the expected benefits of file prefetching and the cost of expected buffer usage. We describe 1-Marginal CBA, an approach that employs probabilistic predictions, as opposed to deterministic hints. We present a probabilistically optimal, though intractable, algorithm, Opt, for a representative prediction model, and demonstrate that any other optimal algorithm under that model will also be intractable. We argue that in many circumstances 1-Marginal and Opt will make the same decisions. Finally, we present simulation results in which 1-Marginal reduced I/O time by an average of 19% and a maximum of 49% over other prefetching schemes in the literature, even when using the same predictor. Since the cost of 1-Marginal is comparable to that of other published algorithms the improvement is real.
Progressive Image Coding using Augmented Zerotrees of Wavelet Coefficients
Authors: Nasir Rajpoot
Venue:  (1998)

Most state-of-the-art image compression techniques exploit the dependencies between the subbands in a wavelet transformed image. We propose a progressive image coding technique which is based upon the augmented zerotrees of wavelet coefficients. An augmented zerotree can be regarded as a spatial orientation tree with some extended characteristics. Both the coder and decoder require to maintain only one list. The augmented zerotrees are constructed in an efficient recursive manner and the algorithms are provided. A comparison reveals that the coder performance is close to, and sometimes outperforms, other well known coding methods. Suggestions are made for further improvements regarding the speed and compression performance of the coder.
Analysis of the Worst Case Space Complexity of a PR Quadtree
Authors: Sriram V. Pemmaraju, Clifford A. Shaffer
Venue:  (1992)

We demonstrate that a resolution-r PR quadtree containing n points has, in the worst case, at most nodes. This captures the fact that as n tends towards 4r, the number of nodes in a PR quadtree quickly approaches O(n). This is a more precise estimation of the worst case space requirement of a PR quadtree than has been attempted before.
Towards a Calculus of Systems Dependability
Authors: Zhiming Liu, Anders P. Ravn, Erlin V. Sorensen, Chaochen Zhou
Venue:  (1992)

This paper presents a calculus that enables a designer of an embedded, real-time system to reason about and calculate whether a given requirement will hold with a sufficiently high probability for given failure probabilities of components used in the design of the system. The main idea is: . to specify requirements and design in DC (Duration Calculus, an extension of real-time, interval logic). . to define satisfaction probabilities for formulas in this calculus. . to establish a basic probabilistic calculus, PC, with rules that support calculation of the satisfaction probability for a composite formula from probabilities of its constituents . and - finally - to develop a collection of theorems expressing specific important PC formulas in terms of the probability matrices used in classical reliability engineering. These theorems are oriented towards systematic numerical calculations. This ensures that reasoning about probabilities is consistent with requirements and design decisions. We thus avoid introducing separate models for requirements and dependability analysis. The system model is a finite automaton with fixed transition probabilities. This defines discrete Markov processes as basis for the calculus.
The Weizmann Workshop on Probabilistic Proof Systems
Authors: U. Feige, S. Goldwasser
Venue:  (1994)

The Weizmann Workshop on Probabilistic Proofs and Applications to Program Checking, Cryptography, and Hardness of Approximation was held at the Weizmann Institute of Science, on January 10-13, 1994. The following report provides the abstracts of the talks given at the workshop, the list of participants, and relevant references.
TOWARDS DOMAIN-INDEPENDENT MACHINE INTELLIGENCE
Authors: Robert Levinson
Venue:  (1993)

Adaptive predictive search (APS), is a learning system framework, which given little initial domain knowledge, increases its decision-making abilities in complex problems domains. In this paper we give an entirely domain-independent version of APS that we are implementing in the PEIRCE conceptual graphs workbench. By using conceptual graphs as the ``base language" a learning system is capable of refining its own pattern language for evaluating states in the given domain that it finds itself in. In addition to generalizing APS to be domain-independent and CG-based we describe fundamental principles for the development of AI systems based on the structured pattern approach of APS. It is hoped that this effort will lead the way to a more principled, and well-founded approach to the problems of mechanizing machine intelligence. The APS framework has been applied to a number of complex problem domains (including chess, othello, pente and image alignment) where the combinatorics of the state space is large and the learning process only receives reinforcement at the end of each search. The unique features of the APS framework are its pattern-weight representation of control knowledge and its integration of several learning techniques including temporal difference learning, simulated annealing, and genetic algorithms. Morph, an APS chess sytem, is now being translated into PEIRCE.
On the Relationship Between the Object-Oriented Paradigm and Software Reuse: An Empirical Investigation
Authors: John A. Lewis, Sallie M. Henry, Dennis G. Kafura, Robert S. Schulman
Venue:  (1992)

This paper describes the results of a controlled experiment designed to evaluate the impact of the object-oriented paradigm on software reuse. The experiment concludes that (1) the object-oriented paradigm substantially improves productivity over the procedural paradigm, (2) language differences are far more important when programmers reuse than when they do not, (3) under both moderate and strong encouragement to reuse, the object-oriented paradigm promotes higher productivity than the procedural paradigm, (4) software reuse improves productivity no matter which language paradigm is used, and (5) the object-oriented paradigm has a particular affinity to the reuse process.
The Cycle Contraction Mapping Theorem
Authors: S. G. Matthews
Venue:  (1992)

This report lays the foundation for a theory of total correctness for programs not based upon termination. The Cycle Contraction Mapping Theorem is both an extension of Wadge''s cycle sum theorem for Kahn data flow and a generalisation of Banach''s contraction mapping theorem to a class of quasi metric spaces definable using the symmetric Partial Metric distance function. This work provides considerable evidence that it is possible after all to construct a metric theory for Scott style partial order domains. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
REPRESENTING BOOLEAN FUNCTIONS WITH IF-THEN-ELSE DAGs
Authors: Kevin Karplus
Venue:  (1988)

This article describes the use of binary decision diagrams (BDDs) and if-then-else DAGs for representing and manipulating Boolean functions. Two-cuts are defined for binary decision diagrams, and the relationship is exhibited between general if-then-else expressions and the two-cuts of a BDD for the same function. An algorithm for computing all two-cuts of a BDD in O(n2) time is given. A new canonical form for if-then-else DAGs, analogous to Bryant''s canonical form for BDDs, is introduced. The canonical form is based on representing the lowest non-trivial two-cut in the corresponding BDD, while Bryant''s canonical form represents the highest two-cut. Expressions in Bryant''s canonical form or in the new canonical form are shown to be prime and irredundant. Some applications of if-then-else DAGs to multi-level logic minimization are given, and the Printform transformations for reducing the complexity of if-then-else DAGs are presented.