ppxscal/embedding_network huggingface dataset:
Model Checking Partially Ordered State Spaces
Authors: Scott Hazelhurst, Carl J. H. Seger
Venue:  (1995)

The state explosion problem is the fundamental limitation of verification through model checking. In many cases, representing the state space of a system as a lattice is an effective way of ameliorating this problem. The partial order of the state space lattice represents an information ordering. The paper shows why using a lattice structure is desirable, and why a quaternary temporal logic rather than a traditional binary temporal logic is suitable for describing properties in systems represented this way. The quaternary logic not only has necessary technical properties, it also expresses degrees of truth. This is useful to do when dealing with a state space with an information ordering defined on it, where in some states there may be insufficient or contradictory information available. The paper presents the syntax and semantics of a quaternary valued temporal logic. Symbolic trajectory evaluation (STE) has been used to model check partially ordered state spaces with some success. The limitation of STE so far has been that the temporal logic used (a two-valued logic) has been restricted, whereas a more expressive temporal logic is often useful. This paper generalises the theory of symbolic trajectory evaluation to the quaternary temporal logic, which potentially provides an effective method of model checking an important class of formulas of the logic. Some practical model checking algorithms are briefly described and their use illustrated. This shows that not only can STE be used to check more expressive logics in principle, but that it is feasible to do so.
A Model Formulation of User Interface for Statistical Databases with Perturbed Responses
Authors: Csaba J. Egyhazy
Venue:  (1986)

A statistical database is defined as a collection of N records used to produce summary information only. Each record contains confidential category and data fields of the same fixed length. Category fields are used to identify and select records, while data fields hold other information, mostly numerical.
Compiling Functional Programs to Java Byte-code
Authors: Gary Meehan
Venue:  (1997)

The aim of the G-machine is to deconstruct a functional program, represented as a graph, into a list of linear instructions --- G-Code --- which, when executed, will construct an equivalent graph and reduce it into Weak Head Normal Form. The Java Virtual Machine (JVM) provides a machine-independent execution environment which executes Java byte-code. This byte-code is essentially a machine code for object-oriented programs. It was designed as the target of a Java compiler, but there is no reason why it cannot be used as the target of other languages. In this report we shall look at compiling functional programs down to the JVM, using the G-machine as a guide.
Natural Deduction Based Set Theories: A New Resolution of the Old Paradoxes
Authors: Paul C. Gilmore
Venue:  (1984)

The comprehension principle of set theory asserts that a set can be formed from the objects satisfying any given property. The principle leads to immediate contradictions if it is formalized as an axiom scheme within classical first order logic. A resolution of the set paradoxes results if the principle is formalized instead as two rules of deduction in a natural deduction presentation of logic. This presentation of the comprehension principle for sets as semantic rules, instead of as a comprehension axiom scheme, can be viewed as an extension of classical logic, in contrast to the assertion of extra-logical axioms expressing truths about a pre-existing or constructed universe of sets. The paradoxes are disarmed in the extended classical semantics because truth values are only assigned to those sentences that can be grounded in atomic sentences.
Genetic Algorithms with Local Improvement for Composite LaminateDesign
Authors: N. Kogiso, Layne T. Watson, Z. Gurdal, Robert T. Haftka
Venue:  (1993)

This paper describes the application of a genetic algorithm to the stacking sequence optimization of a composite laminate plate for buckling load maximization. Two approaches for reducing the number of analyses are required by the genetic algorithm are described. First, a binary tree is used to store designs, affording an efficient way to retrieve them and thereby avoid repeated analyses of designs that appeared in previous generations. Second, a local improvements scheme based on approximations in terms of lamination parameters is introduced. Two lamination parameters are sufficient to define the flexural stiffness and hence the buckling load of a balanced, symmetrically laminated plate. Results were obtained for rectangular graphite-epoxy plates under biaxial in-plane loading. The proposed improvements are shown to reduce significantly the number of analyses required for the genetic optimization.
When Ants Attack: Security Issues for Stigmergic Systems
Authors: Weilin Zhong, David Evans
Venue:  (2002)

Stigmergic systems solve global problems by using indirect communication mediated by an environment. Because they are localized and dynamic, stigmergic systems are self-organizing, robust and adaptive. These properties are useful for creating survivable systems, but stigmergic systems also raise new security concerns. Indirect communication makes systems more vulnerable in an open and hostile environment, and feedback mechanisms common to stigmergic algorithms can be exploited by attackers. In this paper we use AntNet, an adaptive routing algorithm inspired by biological ant foraging, to explore some of the security issues for stigmergic systems. We identify possible attacks and analyze their potency. We propose and evaluate mechanisms for defending against these attacks.
A Designer''s Benchmark for Active Database management Systems: 007Meets the BEAST
Authors: A. Geppert, S. Gatziu, K. R. Dittrich
Venue:  (1995)

A benchmark for active database management systems is described. We are particularly interested in performance tests that help to identify performant and inefficient components. Active functionality that is relevant with respect to performance is identified, and a series of tests is designed that measure the efficiency of the performance- critical components. Results obtained from running the benchmark for a concrete system are presented.
Introducing MegaHAL
Authors: Jason Hutchens, Mike Alder
Venue:  (1998)

Conversation simulators are computer programs which give the appearance of conversing with a user in natural language. Alan Turing devised a simple test in order to decide whether such programs are intelligent. In 1991, the Cambridge Centre for Behavioural Studies held the first formal instantiation of the Turing Test. In this incarnation the test was known as the Loebner contest, as Dr. Hugh Loebner pledged a $100,000 grand prize for the first computer program to pass the test. In this paper we give a brief background to the contest, before describing in detail the workings of MegaHAL, the primary author''s entry to the 1998 Loebner contest.
THE PLANAR PIN ASSIGNMENT AND ROUTING PROBLEM (PPARP) IS NP-COMPLETE
Authors: Joel Darnauer
Venue:  (1995)

Many package routing problems involve routing one set of pins to another set of pins in a single layer without regard to how the pins in each set are connected. We call this type of problem a Planar Pin Assignment and Routing Problem (PPARP). Unlike general routing problems which correspond to the NP-complete multi-commodity flow problem, the pin distribution problem seems to have a natural formulation as a single- commodity flow problem, which suggests that it can be solved efficiently. In this paper, we show that the problem is surprisingly NP-complete.
Application Scheduling over Supercomputers: A Proposal
Authors: Walfredo Cirne, Fran Berman
Venue:  (1999)

We discuss how Resource Schedulers for Supercomputers can support Application Scheduling without degrading their own measures of performance. Initial results are presented and a proposal for future research is delineated.
An Experimental Comparison of Genetic Programming and Inductive LogicProgramming on Learning Recursive List Functions
Authors: Lappoon R. Tang, Mary E Califf, Raymond J. Mooney
Venue:  (1998)

This paper experimentally compares three approaches to program induction: inductive logic programming (ILP), genetic programming (GP), and genetic logic programming (GLP) (a variant of GP for inducing Prolog programs). Each of these methods was used to induce four simple, recursive, list-manipulation functions. The results indicate that ILP is the most likely to induce a correct program from small sets of random examples, while GP is generally less accurate. GLP performs the worst, and is rarely able to induce a correct program. Interpretations of these results in terms of differences in search methods and inductive biases are presented.
Validating Software Pipelining Optimizations,
Authors: R. Leviathan, A. Pnueli
Venue:  (2001)

There is a growing awareness, both in industry and academia, of the crucial role of formally proving the correctness of safety-critical components of systems. Most formal verification methods verify the correctness of a high-level representation of the system against a given specification. However, if one wishes to infer from such a verification the correctness of the code which runs on the actual target architecture, it is essential to prove that the high-level representation is correctly implemented at the lower level. That is, it is essential to verify the the correctness of the translation from the high-level source-code representation to the object code, a translation which is typically performed by a compiler (or a code generator in case the source is a specification rather than a programming language). Formally verifying a full-fledged optimizing compiler, as one would verify any other large program, is not feasible due to its size, ongoing evolution and modification, and, possibly, proprietary considerations. The translation validation method used in this paper is a novel approach that offers an alternative to the verification of translators in general and compilers in particular. According to the translation validation approach, rather than verifying the compiler itself, one constructs a validation tool which, after every run of the compiler, formally confirms that the target code produced on that run is a correct translation of the source program. The paper presents a method for translation validation of a specific optimization used to increase the instruction level parallelism in EPIC type of architectures. Based on our general methodology to establish simulation relation between source and target based on computational induction, we describe an algorithm that automatically produces assertions that help i this process.
Statistical Per-Flow Service Bounds in a Network with Aggregate Provisioning
Authors: Jorg Liebeherr, Stephen D. Patek, Almut Burchard
Venue:  (2002)

Scalability concerns of QoS implementations have stipulated service architectures where QoS is not provisioned separately to each flow, but instead to aggregates of flows. This paper determines stochastic bounds for the service experienced by a single flow when resources are managed for aggregates of flows and when the scheduling algorithms used in the network are not known. Using a recently developed statistical network calculus, per-flow bounds can be calculated for backlog, delay, and the burstiness of output traffic.
Propagation of vibrations from a railway track lying on a semi-infinite soft ground
Authors: B. Picoux, G. Lefeuve-Mesgouez, D. Le Houédec
Venue: Proceedings of the eighth international conference on The application of artificial intelligence to civil and structural engineering computing (2001)

The study of ground vibrations due to moving loads is of great importance in high speed railway transportation [3] on soft ground [5].In this paper, the transmission of vibrations generated by a train in a homogeneous half-space through a railway track is investigated theoretically. Numerical results are given showing the effects of intrinsic parameters of the track and the influence of the train speed on displacements on the surface of the ground.For "super-Rayleigh" regime, Mach cones can be observed near the track. For certain ranges of frequency, an increase of vibration amplitude and an extension of the sollicitation along the displacement line are noticed.
Parametrisation of the speech space using the self-organising neural network
Authors: Roberto Togneri, Mike Alder, Yianni Attikiouzel
Venue:  (1990)

Speech recognition is a difficult problem due to the inability of current systems to cope with connected speech. Neural networks are able to learn some aspects of this task. An unsupervised learning scheme like the self-organising map can be used to both classify and order the speech sounds and provide a front end to higher level processing. A map of phonemes (phonotopic map) is used to trace trajectories of sounds from utterances. The self-organising map provides a means of reducing the inherent dimensionality of the speech data. A crinkle factor which is used to determine how close the dimensionality of the map is to the dimensionality of the speech input shows that speech has an inherent dimensionality of at least three or four. A projection of the map and the speech data shows how the self-organising map fits the speech space.
Formal Verification of Realtime Systems in ASTRAL
Authors: Alberto Coen-Porisini, Richard A. Kemmerer, Dino Mandrioli
Venue:  (1993)

ASTRAL is a formal specification language for realtime systems. It is intended to support formal software development, and therefore has been formally defined. This paper focuses on formally proving the mathematical correctness of ASTRAL specifications. ASTRAL is provided with structuring mechanisms that allow one to build modularized specifications of complex systems with layering. In this paper, we exploit and enhance ASTRAL''s structure and provide a proof method that allows one to build well structured proofs. Correctness proofs in ASTRAL can be divided into two categories: inter- level proofs and intra-level proofs. The former deal with proving that the specification of level i+1 is consistent with the specification of level i, while the latter deal with proving that the specification of level i is correct. In this paper we concentrate on intra-level proofs.
LINEAR TIME UNIT RESOLUTION FOR PROPOSITIONAL FORMULAS--IN PROLOG, YET
Authors: Allen VanGelder
Venue:  (1995)

A procedure to analyze a propositional formula in clause form by unit resolution is described and illustrated with a Prolog implementation. It runs in worst-case time that is linear in the length of the formula. The main idea has been independently rediscovered by several implementers. Apparently, its first journal appearance was a sketch by Dalal and Etherington in 1992. However, there also had arisen a folkloric belief that unit resolution requires quadratic time. This report shows that the implementation sketched for imperative languages, such as C, consumes quadratic time if translated to Prolog. This degradation occurs even if clause indexing permits the retrieval of an asserted clause in constant time. It is rather due to the way Prolog handles assertions involving data structures, such as lists. A modified Prolog implementation that restores linear time is described. The time remains linear even if the procedure is run ``on-line'''', meaning that new clauses appear in the input as processing proceeds. This property is useful in applications that have several mechanisms for deriving new clauses. The technique may have application in other problems that can be described as inductive closures on finite domains. Ad hoc solutions to such problems are error-prone and often inefficient.
LNTP --- An Efficient Transport Protocol for Local Area Networks
Authors: Samuel T. Chanson, K. Ravindran, Stella Atkins
Venue:  (1985)

As interests in local area networks (LANs) grow so is the demand for protocols that run on them. It is convenient and a common practice to adopt existing transport protocols that had been designed for long haul networks (LHNs) for use in LANs. DARPA''s Transmission Control Protocol/lnternet Protocol (TCP/IP) for example, is available in 4.2 BSD UNIX for interface to Ethernet and other LANs. This is not desirable from a performance standpoint as the control structure is usually much more complex than is necessary, and LANs and LHNs have very different characteristics. Though there exists simpler transport protocols such as the User Datagram Protocol (UDP) most do not provide adequate flow control which, because of the much higher channel speed, is critical in the LAN environment. This paper discusses the unique characteristics and requirements of LANs and describes a new transport level protocol (LNTP) specifically designed for use on LANs. The fundamental philosophy in the design of LNTP is simplicity. Any features irrelevant to the LAN environment is not included. As well, LNTP uses a simple but effective deferred flow control mechanism which is activated only when the traffic intensity exceeds some value. This protocol has been implemented and runs under 4.2 BSD UNIX in place of TCP/IP. Detailed comparisons between LNTP, TCP and a few other protocols are given in the paper. Measurement data showed an improvement in network throughput rate of at least 30%, over that of TCP. The problem of internet communication is also addressed.
Adaptive Algorithms for Cache-Efficient Trie Search
Authors: Anurag Acharya, Huican Zhu, Kai Shen
Venue:  (1998)

In this paper, we present cache-efficient algorithms for trie search. There are three key features of these algorithms. First, they use different data structures (partitioned-array, B-tree, hashtable, vectors) to represent different nodes in a trie. The choice of the data structure depends on cache characteristics as well as the fanout of the node. Second, they adapt to changes in the fanout at a node by dynamically switching the data structure used to represent the node. Third, the size and the layout of individual data structures is determined based on the size of the symbols in the alphabet as well as characteristics of the cache(s). We evaluate the performance of these algorithms on real and simulated memory hierarchies. Our evaluation indicates that these algorithms out-perform alternatives that are otherwise efficient but do not take cache characteristics into consideration. A comparison of the number of instructions executed indicates that these algorithms derive their performance advantage primarily by making better use of the memory hierarchy.
A Characterizing Diagonases and Systems
Authors: Johan de Kleer, Alan K. Mackworth, Raymond Reiter
Venue:  (1990)

Most approaches to model-based diagnosis describe a diagnosis for a system as a set of failing components that explains the symptoms. In order to characterize the typically very large number of diagnoses, usually only the minimal such sets of failing components are represented. This method of characterizing all diagnoses is inadequate in general, in part because not every superset of the faulty components of a diagnosis necessarily provides a diagnosis. In this paper we analyze the notion of diagnosis in depth exploiting the notions of implicate/implicant and prime implicate/implicant. We use these notions to propose two alternative approaches for addressing the inadequacy of the concept of minimal diagnosis. First, we propose a new concept, that of kernel diagnosis, which is free of the problems of minimal diagnosis. Second, we propose to restrict the axioms used to describe the system to ensure that the concept of minimal diagnosis is adequate.
Link Strength in Bayesian Networks
Authors: Brent Boerlage
Venue:  (1994)

Automation of software configuration management is an important practical problem. Any automated tool must work from some specifications of correct or desired configurations. This report introduces a language for describing acceptable configurations of common systems, so that automated management is possible. The proposed language is declarative, while at the same time there are efficient algorithms for modifying a system to conform to a specification in many cases of practical importance.
Syntax-basiertes Program-Slicing von COBOL-Programmen
Authors: Zafer Oeztuerk
Venue:  (1995)

Wir stellen mehrere Ansaetze fuer das syntax-basierte Program-Slicing vor, die ausschliesslich gestuetzt auf Informationen aus den Cross- Referencer operieren. Dadurch lassen sich unsere Ansaetze auch da einsetzen, wo die interne Datenrepraesentation aus der Uebersetzungsphase des Compilers fuer das Program-Slicing nicht zur Verfuegung steht.
Responding to the unexpected
Authors: Yigal Arens, Paul S. Rosenbloom
Venue: Communications of the ACM (2003)

How IT can help prepare for future attacks and disasters.
Closure Lattices
Authors: John L. Pfaltz
Venue:  (1994)

Atomic, upper semi-modular lattices, or geometric lattices, have been well studied because of their connections with matroids, projective geometries, subspaces of vector spaces, and other mathematical areas of interest. Closure lattices, although also very regular, are neither atomic nor semi-modular and so have been largely ignored. Yet, they arise naturally in the study of partial order relations, or acyclic directed graphs. 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
The connectivity sonar: detecting site functionality by structural patterns
Authors: Einat Amitay, David Carmel, Adam Darlow, Ronny Lempel, Aya Soffer
Venue: Proceedings of the fourteenth ACM conference on Hypertext and hypermedia (2003)

Web sites today serve many different functions, such as corporate sites, search engines, e-stores, and so forth. As sites are created for different purposes, their structure and connectivity characteristics vary. However, this research argues that sites of similar role exhibit similar structural patterns, as the functionality of a site naturally induces a typical hyperlinked structure and typical connectivity patterns to and from the rest of the Web. Thus, the functionality of Web sites is reflected in a set of structural and connectivity-based features that form a typical signature. In this paper, we automatically categorize sites into eight distinct functional classes, and highlight several search-engine related applications that could make immediate use of such technology. We purposely limit our categorization algorithms by tapping connectivity and structural data alone, making no use of any content analysis whatsoever. When applying two classification algorithms to a set of 202 sites of the eight defined functional categories, the algorithms correctly classified between 54.5% and 59% of the sites. On some categories, the precision of the classification exceeded 85%. An additional result of this work indicates that the structural signature can be used to detect spam rings and mirror sites, by clustering sites with almost identical signatures.