ppxscal/embedding_network huggingface dataset:
Entropy and Enumeration
Authors: Nicholas Pippenger
Venue:  (1998)

Shannon''s notion of the entropy of a random variable is used to give simplified proofs of asymptotic formulas for the logarithms of the numbers of monotone Boolean functions and Horn functions, and for equivalent results concerning families of sets and closure operations.
Attainable Resource Allocations Bounds
Authors: Emile K. Haddad
Venue:  (1989)

Upper and lower bounds attained by the variables of a generalized resource allocation problem are distinguished from the a priori specified bounds defining the feasible set. General theoretical criteria directly relating attainable bounds to specified bounds are presented, which are computationally superior to the traditional "modified simplex method."
SOME FUTURE DIRECTIONS IN FAULT MODELING AND TEST PATTERN GENERATION RESEARCH
Authors: F. J Ferguson, Tracy Larrabee
Venue:  (1992)

This document presents the current state of fault modeling research and lists research options that leverage the Carafe-Nemesis software packages and the knowledge gained from their use.
Technical Report - The Hough Transform versus the UpWrite
Authors: Robert McLaughlin, Michael Alder
Venue:  (1997)

This paper compares the Hough Transform and the UpWrite for the detection of lines, circles and ellipses. Both ideal and noisy images are tested. The UpWrite is found to be more robust for images containing perturbation noise. For ideal images and images with speckle noise, the results are found to depend on the complexity of the object being detected, with more complex objects favouring the UpWrite. A program allowing the reader to experiment with these algorithms can be found at the WWW address http://ciips.ee.uwa.edu.au/Papers/Technical_Reports/1997/02/Index.html
A Lexical Relation Hierarchy
Authors: Jane T Nutter
Venue:  (1989)

An extensive literature now exists documenting various lexical relations for representing information about words. This report summarizes the lexical relations recognized in a variety of sources. In addition, we claim that lexical relations themselves form not a class but a taxonomy, with a rich hierarchical structure. We present the outlines of this taxonomy, organize relations identified in a number of works under the taxonomy, and then give a condensed report of over 100 relations derived from the compendium, organized by their hierarchical status.
Cartesian products of graphs as subgraphs of de Bruijn graphs of dimension atleast three
Authors: Thomas Andreae, Martin Hintz, Michael Nolle, Gerald Schreiber, Gerald Schuster, Hajo Seng
Venue:  (1995)

Given a Cartesian product G=G_1timesldotstimes G_m;(mgeq2) of nontrivial connected graphs G_i and the base d, dimension D de Bruijn graph B(d,D), it is investigated under which conditions G is (or is not) a subgraph of B(d,D). We present a complete solution of this problem for the case Dgeq4. For D=3, we give partial results including a complete solution for the case that G is a torus, i.e., G is the Cartesian product of cycles.
Numerical modelling of ground anchorages employed in the field
Authors: A. Ivanovic, A. Starkey, R. D. Neilson, A. A. Rodger
Venue: Proceedings of the eighth international conference on The application of artificial intelligence to civil and structural engineering computing (2001)

A research programme into both the static and dynamic performance of ground anchorage systems, with an emphasis on resin bonded rock bolts, started at the University of Aberdeen in the early 1980s. The work involved measurements on active construction sites which was underpinned by laboratory and computer modelling and lead to the development of a new method for the non-destructive testing of anchorages. Part of the research programme was focused on assessing how changes in the load influence the dynamic responses of an anchorage. This in turn produced a new testing method able to determine the variation in frequency response of the anchorage with changes in load. The development of a lumped parameter model able to simulate the response of anchorages to changes in static load and an applied impulse load was a further step forward in the research programme. The achievements of the lumped parameter model revealed the head of the anchorage to be the most influential component of the anchorage system in determining dynamic response. The results obtained from the numerical model when laboratory anchorages were simulated are shown to be in agreement with the results obtained from the actual laboratory tests. Based on the successful results obtained to date regarding laboratory tendon anchorages a further step was made in order to employ the numerical model for the first time to observe the influence of load on the frequency response of rock bolt anchorages installed in the field.
A More Cost Effective Algorithm for Finding Perfect Hash Functions
Authors: Edward A. Fox, Qi Chen, Lenwood S. Heath, Sanjeev Datta
Venue:  (1988)

As the use of knowledge-based systems increases, there will be a growing need for efficient artificial intelligence systems and methods to access large lexicons. In the Composite Document Expert/extended/effective Retrieval (CODER) system we have, in order to provide rapid access to data items on CD-ROM''s and to terms in a lexicon built from machine readable dictionaries, investigated the construction of perfect hashing functions. We have considered algorithms reported earlier in the literature, have made numerous enhancements to them, have developed new algorithms, and here report on some of our results. This paper covers an $O(n^3)$ algorithm that has been applied to building hashing functions for a collection of 69806 words on a CD-ROM. Most recently we have developed a much better algorithm and have succeeded in finding a perfect hash function for a set of 5000 words taken from the Collins English Dictionary.
Cooperative learning and virtual reality-based visualization for data mining
Authors: Herna Viktor, Eric Paquet, Gys le Roux
Venue: Data mining: opportunities and challenges (2003)

Data mining concerns the discovery and extraction of knowledge chunks from large data repositories. In a cooperative datamining environment, more than one data mining tool collaborates during the knowledge discovery process. This chapter describes a data mining approach used to visualize the cooperative data mining process. According to this approach, visual data mining consists of both data and knowledge visualization. First, the data are visualized during both data preprocessing and data mining. In this way, the quality of the data is assessed and improved throughout the knowledge discovery process. Second, the knowledge, as discovered by the individual learners, is assessed and modified through the interactive visualization of the cooperative data mining process and its results. The knowledge obtained from the human domain expert also forms part of the process. Finally, the use of virtual reality-based visualization is proposed as a new method to model both the data and its descriptors.
LSCs: Breathing Life into Message Sequence Charts
Authors: W. Damm, D. Harel
Venue:  (1998)

While message sequence charts (MSCs) are widely used in industry to document the interworking of processes or objects, they are expressively quite weak, being based on the modest semantic notion of a partial ordering of events as defined, e.g., in the CCITT standard. A highly expressive and rigorously defined MSC language is a must for serious, semantically meaningful tool support for use-cases and scenarios. It is also a prerequisite to addressing what we regard as one of the central problems in behavioral specification of systems: relating scenario-based inter-object specification to state-machine intra-object specification. This paper proposes an extension of MSCs, which we call live sequence charts (or LSCs), since one of our main extensions deals with specifying ``liveness", i.e., things that must occur. In fact, LSCs allow the distinction between possible and necessary behavior both globally, on the level of an entire chart and locally, when specifying events, conditions and progress over time within a chart. We also deal with subcharts, synchronization, branching and iteration.
LOGICAL DEFINABILITY OF NP OPTIMIZATION PROBLEMS
Authors: Phokion G. Kolaitis, Madhukar N. Thakur
Venue:  (1990)

We investigate here NP optimization problems from a logical definability standpoint. We show that the class of optimization problems whose optimum is definable using first-order formulae coincides with the class of polynomially bounded NP optimization problems on finite structures. After this, we analyze the relative expressive power of various classes of optimization problems that arise in this framework. Some of our results show that logical definability has different implications for NP maximization problems than it has for NP minimization problems, in terms of both expressive power and approximation properties.
DISTRIBUTED ALGORITHMS FOR MULTICAST PATH SETUP IN DATA NETWORKS
Authors: Fred Bauer, Anujan Varma
Venue:  (1995)

Establishing a multicast tree in a point-to-point network of switch nodes, such as a wide-area ATM network, can be modeled as the NP-complete Steiner problem in networks. In this paper, we introduce and evaluate two distributed algorithms for finding multicast trees in point-to-point data networks. These algorithms are based on the centralized Steiner heuristics SPH and K-SPH, and have the advantage that only the multicast members and nodes in the neighborhood of the multicast tree need to participate in the execution of the algorithm. We compare our algorithms by simulation against a baseline algorithm, the pruned minimum spanning-tree heuristic, which is the basis of many previously published algorithms for finding multicast trees. Our results show that the quality of the solutions produced by both of our algorithms were on the average 25~percent better in comparison to those produced by the pruned spanning-tree approach. In addition, the quality of solution found by our algorithms in almost all cases was within 10% of the best solution found by any of the Steiner heuristics considered, including both centralized or distributed algorithms. Limiting the execution of the algorithm to a subset of the nodes in the network results in an increase in convergence time over the pruned spanning-tree approach, but this overhead can be reduced by careful implementation.
Additive Increase Appears Inferior
Authors: Sergey Gorinsky, Harrick Vin
Venue:  (2000)

Feedback-based adjustment of load is a common mechanism for resource allocation in computer networks. This paper disputes the popular beliefs that the additive-increase multiplicative-decrease adjustment policy is optimal or even necessary for convergence to fair resource sharing. We demonstrate that, in the classic synchronous model, additive increase does not guarantee the quickest convergence of fairness. Moreover, not only fairness but also efficiency converges very slowly under additive increase. For an asynchronous model, we show that the additive-increase multiplicative-decrease algorithm fails to converge to optimal fairness. We observe that the TCP congestion control algorithm suffers from the problems detected by our analysis and is unfair.
Even Kernels
Authors: A. S. Fraenkel
Venue:  (1994)

Given a graph G = (V,E), an even kernel is a nonempty independent subset V? I V, such that every vertex of G is adjacent to an even number (possibly 0) of vertices in V?. It is proved that the question of whether a graph has an even kernel is NP-complete. The motivation stems from combinatorial game theory. It is known that this question is polynomial if G is bipartite. We also prove that the question of whether there is an even kernel whose size is between two given bounds, in a given bipartite graph, is NP-complete. This result has applications in coding and set theory.
Representing Techniques in Computer System Design \& Load Control
Authors: Mercer Robert Ernest, Reiter Raymond
Venue:  (1982)

This paper is a first step towards the computation of an inference based on \underline{language use}, termed \underline{presupposition}. Natural languages, unlike formal languages, can be \underline{semantically ambiguous}. These ambiguities are resolved according to \underline{pragmatic rules}. We take the position that presuppositions are inferences generated from these pragmatic rules. Presuppositions are then used to generate the \underline{preferred interpretation} of the ambiguous natural language sentence. A preferred interpretation can be circumvented by an explicit inconsistency. This paper discusses the appropriateness of using \underline{default rules} (Reiter(1980)) to represent certain common examples of presupposition in natural language. We believe that default rules are not only appropriate for representing presuppositions, but also provide a formal explanation for a precursory consistency-based presuppositional theory (Gazdar(1979)).
Computer Science Seminars 1992/93
Authors: M. S. Paterson
Venue:  (1993)

This report contains the abstracts of the programme of weekly seminars in the Department of Computer Science for the 1992/93 academic year. There were 28 seminars in all: 17 by external speakers and 11 from within the Department. With few exceptions, the seminars were held in the Department''s Seminar Room on Tuesday afternoons at 4pm after an informal gathering for refreshments. 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
Multi Process Structuring of X.25 Software
Authors: Stephen E Deering
Venue:  (1982)

Modern communication protocols present the software designer with problems of asynchrony, real-time response, high throughput, robust exception handling, and multi-level interfacing. An operating system which provides lightweight processes and inexpensive inter-process communication offers solutions to all of these problems. This thesis examines the use of the multi-process structuring facilities of one such operating system, Verex, to implement the protocols defined by CCITT Recommendation X.25. The success of the multi-process design is confirmed by a working implementation that has linked a Verex system to the Datapac public network for over a year. .br The processes which make up the Verex X.25 software are organized into layers according to the layered definition of X.25. Within the layers, some processes take the form of finite-state machines which execute the state transitions specified in the protocol definition. Matching the structure of the software to the structure of the specification results in software which is easy to program, easy to understand, and likely to be correct. .br .br Multi-process structuring can be applied with similar benefits to protocols other than X.25 and systems other than Verex.
A Controlled Experiment to Evaluate Maintainability ofObject-Oriented Software
Authors: Sallie M. Henry, Matthew C. Humphrey
Venue:  (1990)

New software tools and methodologies make claims that managers often believe intuitively without evidence. Many unsupported claims have been made about object-oriented programming. However, without scientific evidence, it is impossible to accept these claims as valid. Although experimentation has been done in the past, most of the research is very recent and the most relevant research has serious drawbacks. This paper describes an experiment which compares the maintainability of two functionally equivalent systems, in order to explore the claim that systems developed with object-oriented languages are more easily maintained than those programmed with procedural languages. We found supporting evidence that programmers produce more maintainable code with an object-oriented language than with a standard procedural language.
The Implementation of Four Conceptual Frameworks for Simulation Modeling in High-Level Languages
Authors: Osman Balci
Venue:  (1988)

This is a tutorial paper on how to implement a simulation model in a high-level programming language (e.g ., C, Pascal, FORTRAN) by using the following conceptual frameworks (also called world views, simulation strategies, and formalisms): (1) event scheduling, (2) activity scanning, (3) three-phase approach, and (4) process interaction. Implementation details under each conceptual framework are covered in a high level without being concerned about execution efficiency. The purpose is to reveal the characteristics of the four conceptual frameworks so that the programmer can select and implement one to achieve certain model quality characteristics such as maintainability, reusability, and execution efficiency. A problem is defined for use as an example for illustrating the concepts throughout the paper.
Reducing the Overhead of Compilation Delay
Authors: Chandra Krintz, David Grove, Derek Lieber, Vivek Sarkar, Brad Calder
Venue:  (2000)

The execution model for mobile dynamically-linked object--oriented programs has evolved from fast interpretation to a mix of interpreted and dynamically compiled execution. The primary motivation for dynamic compilation is that compiled code executes significantly faster than interpreted code. However, since dynamic compilation is performed while the application is running, the biggest challenge in using dynamic compilation is to reduce its overhead so as not to mitigate the runtime improvement that it delivers. Techniques for reducing dynamic compilation overhead can be classified as (1) decreasing the amount of compilation performed, or (2) overlapping compilation with useful work. In this paper, we first evaluate the effectiveness of Lazy Compilation as a technique for decreasing the amount of compilation performed. In lazy compilation, individual methods are compiled on demand (when called), thus avoiding the load-time delay of compiling all methods when a new class/module is loaded. Our experimental results (obtained by executing the specJVM Java programs on the Jalapeno JVM) show that lazy compilation results in compilation of 57% to 63% fewer methods, and a reduction in compilation time of approximately 30%, when compared to load-time compilation. Next, we present Profile-driven Background Compilation as a new technique for overlapping compilation with execution. The motivation for background compilation is to use idle cycles in multiprocessor systems to overlap compilation with application execution. Profile information is used to prioritize methods as candidates for background compilation. Our results show that background compilation can deliver significant reductions (26% to 79%) in total time i.e., compilation plus execution time, compared to serial (non-background) compilation.
Magnetohydrodynamic Flow Past a Porous Rotating Disk In a Circular Magnetic Field
Authors: Kishore S. Kumar, William I. Thacker, Layne T. Watson
Venue:  (1987)

This paper studies the effects of a circular magnetic field on the flow of a conducting fluid about a porous rotating disk. Using modern quasi-Newton and globally convergent homotopy methods, numerical solutions are obtained for a wide range of magentic field strengths, suction and injection velocities and Alfven and disk speeds. Results are presented graphically in terms of three nondimensional parameters. There is excellent agreement with previous work and asymptotic formulas.
Cultivating Requirements in a Situated Requirements Engineering Process
Authors: Pi Sun, S. B. Russ, Y. C. Chen, W. M. Beynon
Venue:  (1999)

The fact that requirements are situated motivates an alternative to conventional process models that gives adequate recognition to the situatedness of the requirements engineering process (REP). This paper proposes a problem-oriented framework SPORE (situated process of requirements engineering) whereby requirements as solutions to the identified problems in the application domain are developed in an open-ended and situated manner. Within this framework, people participating in the REP are able to cultivate requirements through collaborative interaction with each other for solving the identified problems, rather than to search for requirements from the jungle of users'' needs. For a given application, a family of artefacts or interactive situation models (ISM) are developed which form the medium for the problem-solving process of requirements cultivation. These ISMs are built using the principles and tools of the Empirical Modelling, a novel approach to computer-based modelling. Participants can create and use these models not only as artefacts to explore, expand and experience the solutions to the identified problems, but also as a powerful means of supporting their collaborative interaction for ''growing up'' the solutions in a distributed environment. A case study of applying this framework to cultivate requirements for a warehouse distribution system is given.
Linking Simulation Model Specification and Parallel Execution through UNITY
Authors: Marc Abrams, Ernest H. Page, Richard E. Nance
Venue:  (1991)

Chandy and Misra''s UNITY is a computation model and proof system suitable for development of parallel (and distributed) programs through step-wise refinement of specifications. UNITY supports the development of correct programs and the efficient implementation of those programs on parallel computer architectures. This paper assesses the potential of UNITY for simulation model specification and implementation by developing a UNITY specification of the machine interference problem with a patrolling repairman service discipline. The conclusions reached are that the UNITY proof system can assist formal verification of simulation models and the UNITY mappings of programs to various computer architectures offer some potential for assisting the automatic implementation of simulation models on parallel architectures. The paper gives some insights into the relationship of time flow mechanisms, parallel simulation protocols, and target parallel computer architectures.
Exploiting Coauthorship to Infer Topicality in a Digital Library of Computer Science Technical Reports
Authors: James C. French, Charles L. Viles
Venue:  (1996)

We propose a method of mapping the topical content of distributed digital libraries and demonstrate the technique using data from the Networked Computer Science Technical Report Library (NCSTRL) digital library project. This method seeks to exploit information derived from document coauthorship to produce improved automatic subject classifications of the documents. In a distributed digital library, these subject classifications are useful in characterizing both intra-site and inter-site content. They are also helpful in providing secondary retrieval services. We present the method and describe an experiment and results showing that improved clusterings can be achieved relative to traditional document clustering.
On the Algorithmics of Higraphs
Authors: O. Grossman, D. Harel
Venue:  (1997)

This paper initiates an algorithmic investigation of higraphs, a formalism proposed in 1988 that combines and extends graphs and Euler/Venn diagrams. We first provide higraphs with a syntax and semantics that minimize ambiguities in the interpretation. We then consider some basic properties of higraphs, such as shortest paths, Hamiltonian cycles, bipartition, and minimum cover, and seek algorithms to test for them. In some cases, like shortest paths, the algorithms and the bounds from graphs can be generalized to higraphs, but in others, such as Hamiltonian cycles, the situation is not as clear.