ppxscal/embedding_network huggingface dataset:
Lexicographically Ordered Functional Dependencies and Their Application to Temporal Relations
Authors: Wilfred Ng
Venue: Proceedings of the 1999 International Symposium on Database Engineering & Applications (1999)

We propose the ordered relational model and define Lexicographically Ordered Functional Dependencies (LOFDs) according to the lexicographical ordering on the Cartesian product of the domains associated with the involved attributes. An LOFD in the ordered relational model captures the semantics of a monotonicity property between two sets of data. We establish a set of sound and complete chase rules for LOFDs, and show that the implication problem for LOFDs is decidable. Defining temporal relations as a special case of linearly ordered relations over schemas consisting of the time, time-variant, and time-invariant attributes, we demonstrate that LOFDs are a useful semantic constraint, which can be employed to maintain the consistency between the time data in different time measurement systems. We also formally define Temporal Functional Dependencies (TFDs) in order to express the semantics of the temporally ordered data. A TFD can be expressed in term of a set of LOFDs, in which every element has a sequence of time attributes on its left-hand side and a single time-variant attribute on its right-hand side. Finally, we exhibit a sound and complete axiom system for TFDs.
Object-Centred Planning: Lifting Classical Planning from the Literal Level to the Object Level
Authors: T. L. McCluskey, D. E. Kitchin, J. M. Porteous
Venue: Proceedings of the 8th International Conference on Tools with Artificial Intelligence (1996)

A great deal of emphasis in classical AI planning research has been placed on search-control issues in plan generation, while the issue of knowledge representation and acquisition of models for use with classical planning engines has been largely ignored. Work in knowledge-based planning, on the other hand, is often associated with `scruffy' AI, there being no standard representation languages with associated formal semantics for encoding domain models. In this paper we describe a method to create a planning domain model which preserves the domain independence, generality and `clean' properties of generative planners to which the model can be attached. Our method is based on lifting the level of domain representation from the literal-centred, to the object-centred. This object-centred method has the advantage that it naturally allows for the creation of a supporting tools environment to help in (i) the creation and validation of a precise planning model, and (ii) the speed-up of plan generation.
A Framework for Structured Distributed Object Computing
Authors: K. M Chandy, Joseph Kiniry, Adam Rifkin, Daniel Zimmerman, Wesley Tanaka, Luke Weisman
Venue:  (1997)

This paper presents a four-faceted framework for distributed applications that use worldwide networks connecting large numbers of people, software tools, monitoring instruments, and control devices. We describe a class of applications, identify requirements for a framework that supports these applications, and propose a design fulfilling those requirements. We discuss some initial experiences using the framework, and compare our design with other approaches.
Transactional programming for distributed agent systems
Authors: V. K. Murthy
Venue: Proceedings of the 1996 International Conference on Parallel and Distributed Systems (1996)

A new multiagent programming paradigm based on the transactional logic model is developed. This paradigm enables us to construct a distributed agent transactional program (DATRAP). Such a construction is carried out in two stages: first expressing a program into a production rule system, and then converting the rule applications into a set of transactions on a database of active objects represented using high-level data structures. The formal specification and refinement calculus are key features in the development of a DATRAP. We also indicate how to specify granularity of parallelism and also achieve several types of parallelism. One can associate with a DATRAP two different types of execution semantics called set-based and instance-based semantics. We also show how to prove correctness of DATRAP, achieve maximal concurrence and reduce the complexity of a distributed program.
Anisotropic mechanisms for multiphasic unipolar electrograms. Simulation studies and experimental recordings
Authors: Piero Colli Franzone, Luciano Guerri, Micol Pennacchio, Bruno Taccardi
Venue:  (1999)

The origin of the multiple, complex morphologies observed in unipolar epicardial electrograms, and their relationships with myocardial architecture, have not been fully elucidated. To clarify this problem we simulated electrograms (EGs) with a model representing the heart as an anisotropic bidomain with unequal anisotropy ratio, ellipsoidal ventricular geometry, transmural fiber rotation, epi-endocardial obliqueness of fiber direction and a simplified conduction system. The electrograms were compared with those directly recorded from the surface of isolated dog hearts immersed in a conducting medium. The model accurately reproduced the recorded EG morphologies for excitation wave fronts that reach the recording sites by spreading either along or across fibers.The origin of the multiple waves that constitute the QRS complex could be better understood after splitting the current sources, the potential distributions and the EGs into a field component (further subdivided into an axial and a conormal component) and a "reference" component. The split model provides an explanation of the interaction between the three-dimensional geometry and direction of propagation of a spreading wave front, the architecture of the fibers through which excitation is spreading, the potential distributions and the QRS wave forms. Because epicardial potentials, electrograms and isochrone contours can be computed noninvasively from body surface measurements, interpreting epicardial EGs in terms of intramural events may have clinical relevance. TEL:: +39-0382-505608 KEYWORDS:: Electrograms, bidomain model, reference potential, cardiac potential maps, anisotropic propagation, source splitting EMAIL:: colli@dragon.ian.pv.cnr.it
On Some Tighter Inapproximability Results
Authors: Berman Piotr, Karpinski Marek
Venue:  (1999)

We give a number of improved inapproximability results, including the best up to date explicit approximation thresholds for bounded occurrence satisfiability problems like MAX-2SAT and E2-LIN-2, and the bounded degree graph problems, like MIS, NodeCover, and MAX CUT. We prove also for the first time inapproximability of the problem of Sorting by Reversals and display an explicit approximation threshold.
On the normalization of numbers and functions defined by radicals
Authors: Marc Rybowicz
Venue: Journal of Symbolic Computation (2003)

Based on a criterion due to Kneser, we present new results for the degree of field extensions generated by finitely many radicals. We also improve an algorithm given by Zippel for computing a basis for such an extension field. This algorithm may be effectively used by computer algebra systems to normalize expressions involving radicals.
Better simplification of elementary functions through power series
Authors: James Beaumont, Russell Bradford, James H. Davenport
Venue: Proceedings of the 2003 international symposium on Symbolic and algebraic computation (2003)

In [5], we introduced an algorithm for deciding whether a proposed simplification of elementary functions was correct in the presence of branch cuts. This algorithm used multivalued function simplification followed by verification that the branches were consistent.In [14] an algorithm was presented for zero-testing functions defined by ordinary differential equations, in terms of their power series.The purpose of the current paper is to investigate merging the two techniques. In particular, we will show an explicit reduction to the constant problem [16].
Fast and Compact Error Correcting Scheme for Reliable Multilevel Flash Memories
Authors: D. Rossi, C. Metra, B. Riccò
Venue: Proceedings of the Proceedings of The Eighth IEEE International On-Line Testing Workshop (IOLTW'02) (2002)

This paper presents a method to reduce area and timing overhead due to the implementation of standard single symbol correcting codes to provide ML Flash memories with error correction ability. In particular, the proposed method is based on the manipulation of the parity check matrix which defines a code, which allows to minimize the matrix weight and the maximum row weight. Furthermore, we will show that a minimal increase in the redundancy, with respect tothe standard case, allows a further considerable reduction of the impact on the memory access time, as well as on the area overhed due to the error correction circuitry.
Undecidability Results for Hybrid Systems
Authors: Thomas A. Henzinger, Peter W. Kopke
Venue:  (1995)

We illuminate the boundary between decidability and undecidability for hybrid systems. Adding any of the following decorations to a timed automaton makes the reachability problem undecidable: 1. a single stopwatch with weak (=) edge guards 2. a single skewed clock with variable equality tests 3. a single two-slope clock with weak edge guards 4. a single memory cell with weak edge guards As a corollary, we obtain undecidability for linear hybrid systems with triangular differential inclusions, which have invariants of the form x''>=y''.
Longest prefix matching using bloom filters
Authors: Sarang Dharmapurikar, Praveen Krishnamurthy, David E. Taylor
Venue: Proceedings of the 2003 conference on Applications, technologies, architectures, and protocols for computer communications (2003)

We introduce the first algorithm that we are aware of to employ Bloom filters for Longest Prefix Matching (LPM). The algorithm performs parallel queries on Bloom filters, an efficient data structure for membership queries, in order to determine address prefix membership in sets of prefixes sorted by prefix length. We show that use of this algorithm for Internet Protocol (IP) routing lookups results in a search engine providing better performance and scalability than TCAM-based approaches. The key feature of our technique is that the performance, as determined by the number of dependent memory accesses per lookup, can be held constant for longer address lengths or additional unique address prefix lengths in the forwarding table given that memory resources scale linearly with the number of prefixes in the forwarding table.Our approach is equally attractive for Internet Protocol Version 6 (IPv6) which uses 128-bit destination addresses, four times longer than IPv4. We present a basic version of our approach along with optimizations leveraging previous advances in LPM algorithms. We also report results of performance simulations of our system using snapshots of IPv4 BGP tables and extend the results to IPv6. Using less than 2Mb of embedded RAM and a commodity SRAM device, our technique achieves average performance of one hash probe per lookup and a worst case of two hash probes and one array access per lookup.
Compactly supported tight wavelet frames and orthonormal wavelets of exponential decay with a general dilation matrix
Authors: Bin Han
Venue: Journal of Computational and Applied Mathematics (2003)

Tight wavelet frames and orthonormal wavelet bases with a general dilation matrix have applications in many areas. In this paper, for any d × d dilation matrix M, we demonstrate in a constructive way that we can construct compactly supported tight M-wavelet frames and orthonormal M-wavelet bases in L2(Rd) of exponential decay, which are derived from compactly supported M-refinable functions, such that they can have both arbitrarily high smoothness and any preassigned order of vanishing moments. This paper improves several results in Battle (Comm. Math. Phys. 110 (1987) 601), Bownik (J. Fourier Anal. Appl. 7(2001) 489), Gröchenig and Ron (Proc. Amer. Math. Soc. 126 (1998) 1101), Lemarié (J. Math. Pures Appl. 67 (1988) 227), and Strichartz (Constr. Approx. 9 (1993) 327).
Cost-balanced cooperation protocol in multi-agent robotic systems
Authors: Fang-Chang Lin, J. Y. -J. Hsu
Venue: Proceedings of the 1996 International Conference on Parallel and Distributed Systems (1996)

This paper proposes a cooperation protocol based on the cost-balanced strategy for the Object-Sorting Task in multi-agent robotic systems. The protocol coordinates agents for carrying objects to destinations efficiently and effectively. Each agent autonomously makes subjective optimal decision, then the coordination algorithm resolves their conflicts by balancing the load, which is measured in terms of cost. Since coordination can be performed simultaneously with agent movement, it incurs very little overhead. The protocol is efficient because every agent runs the same algorithm to obtain the common results without further communication. Implementation of the protocol is realized on a distributed modular agent architecture for design simplicity, flexibility, and reactivity. Experimental results have shown that (1) the protocol has better performance than a previously proposed help-based cooperation protocol, (2) the protocol is flexible, and (3) the protocol can effectively utilize the agent power to achieve linear and superlinear speedup in most cases.
Reference History, and Migration - Daemons in Local/Remote Architectures
Authors: Page Size, A M Holliday
Venue:  (1988)

We address the problem of paged main memory management in the local/remote architecture subclass of shared memory multiprocessors. We consider the case where the operating system has primary responsibility and uses page migration as its main tool. We identify some of the key issues with respect to architectural support (reference history maintenance, and page size), and operating system mechanism (duration between daemon passes, and number of migration daemons). The experiments were conducted using software implemented page tables on a 32-node BBN Butterfly Plus $^ {TM}$. Several numerical programs with both synthetic and real data were used as the workload. The primary conclusion is that for the cases considered migration was at best marginally effective. On the other hand, practical migration mechanisms were robust and never significantly degraded performance. The specific results include: 1) Referenced bits with {\em aging} can closely approximate Usage fields, 2) larger page sizes are beneficial except when the page is large enough to include locality sets of two processors, 3) multiple migration daemons can be useful. Only small regions of the space of architectural, system, and workload parameters were explored. Further investigation of other parameter combinations is clearly warranted.
Maintaining a COTS Integrated Solution - Are Traditional Static Analysis Techniques Sufficient for this New Programming Methodology?
Authors: R. Cherinka, J. Ricci, C. M. Overstreet
Venue: Proceedings of the International Conference on Software Maintenance (1998)

As integrating commercial off-the-shelf (COTS) products into new homogeneous systems replaces "traditional" software development approaches, software maintenance problems persist. This approach builds new solutions via "glue code" using visual languages, which tie together client-based office products, server-based "BackOffice" products and web-based services/applications. The resulting collection of distributed object-oriented components are glued together by attaching code snippets written in a visual language to other components and controls, such as a command button on a form. A majority of the code in such an application is pre-generated and self-contained in the individual components being reused and, as a result, is typically difficult to understand and maintain. Our experience shows that, while these approaches actually exacerbate some maintenance problems, such as the introduction of dead code, traditional static analysis techniques may still facilitate common maintenance activities. This work reports on the use of data flow techniques on several medium-sized COTS integrated solutions that have become difficult to maintain. We found that by exploiting semantic information, traditional techniques can be augmented to handle some of the unique maintenance issues of component-based software.
Optimizing Ray Tracing with Visual Coherence
Authors: Nathan Loofbourrow, Steven A. Shafer
Venue:  (1993)

We present a method that directs sampling and reconstruction for image generation. This method reduces the cost of the sampling stage, allows a reconstruction of the scene to be progressively refined during the sampling process, and produces a representation of the scene that permits flexibility in the generation of images. The method employs a set of "region estimators" to model and evaluate the samples that are taken of the image. These models describe coherent regions of the image plane. The region estimators are used to direct the sampling process and to provide a description of the scene for reconstruction. The use of region estimators removes the dependence of the reconstruction process upon the sampling process by providing a compact and accurate representation of the sampled data. This representation permits the resolution and filter kernel to be chosen at reconstruction. An algorithm is presented to perform this reconstruction efficiently.
Creative Problems and Artificial Intelligence Systems
Authors: Igor B. Fominykh
Venue: Proceedings of the 2002 IEEE International Conference on Artificial Intelligence Systems (ICAIS'02) (2002)

The possible technologies of a solution of creative problems on the computer are considered. The special attention accent on a role reflexion, intuition and functional system in solution of this class of problems. 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
Snowflake: Spanning administrative domains
Authors: Jon Howell, David Kotz
Venue:  (1998)

Many distributed systems provide a ``single-system image'''' to their users, so the user has the illusion that they are using a single system when in fact they are using many distributed resources. It is a powerful abstraction that helps users to manage the complexity of using distributed resources. The goal of the Snowflake project is to discover how single-system images can be made to span administrative domains. Our current prototype organizes resources in namespaces and distributes them using Java Remote Method Invocation. Challenging issues include how much flexibility should be built into the namespace interface, and how transparent the network and persistent storage should be. We outline future work on making Snowflake administrator-friendly.
Inductance Aware Interconnect Scaling
Venue: Proceedings of the 3rd International Symposium on Quality Electronic Design (2002)

This paper introduces a new global-tier interconnect scaling scheme which ensures that inductance effects do not start dominating the overall interconnect performance. It is shown that for unscaled global lines, inductance effects increase as technology scales while for the scaling scheme proposed by ITRS [1], interconnects become extremely resistive and, while inductance effects diminish with scaling but the performance, specifically, delay per unit length, degrades with scaling. The effect of the proposed global interconnect scaling scheme on optimized driver size, interconnect length, delay per unit length and total buffer area is quantified and compared with the unscaled and the ITRS cases. It is shown that the proposed scaling scheme improves the delay per unit length without degrading inductive effects or increasing buffer area with scaling.
A Paraconsistent Multiple Inheritance Reasoner
Authors: Braulio Ávila, Fernanda Hembecker
Venue: Proceedings of the Fourth International Conference on Computational Intelligence and Multimedia Applications (2001)

Knowledge representation is of crucial importance in the field of Artificial Intelligence.Although there is no general consensus on what is knowledge representation, many schemes were proposed to represent and store knowledge.This paper focuses on frames.Frames are a knowledge representation scheme allowing the description of complex objects.However, a gap exists between the knowledge represented by framesystems and knowledge in the real world.Few frame systems are concerned with bridging this knowledge gap; they do not handle adequately issues such as exceptionsand the inconsistency phenomenon.In this paper a paraconsistent inheritance reasonerin Paralogue is implemented, representing knowledge by means of paraconsistent frames and making inferences on tangled hierarchies, based on the degree of inconsistency/under-determinedness.
Covers of $PG(3,q) $ and of finite generalized quadrangles
Authors: A. Blokhuis, C. M. O''Keefe, S. E. Payne, L. Storme, H. Wilbrink
Venue:  (1998)

This article studies covers in $\PG(3,q)$ and in generalized quadrangles. The excess of a cover is defined to be the difference between the number of lines in the cover and the number of lines in a spread. In contrast with the theory of partial spreads which tells us that large partial spreads can be extended to spreads, in $\PG(3,q)$ and in some generalized quadrangles, there exist minimal covers with small excess. For such minimal covers with small excess, we describe the structure of the set of points lying on at least two lines of the cover.
A Role for VRML as a Multimedia Backbone in Interpreting Cultural Heritage Sites
Venue: Proceedings of the 1999 International Conference on Information Visualisation (1999)

This paper appraises the role of Virtual reality modelling language (VRML) based 3D computer based models of Historic Environments in increasing access for and assisting the understanding of the general public. It is argued that VRML based 3D models and linked media create a low cost easy to use and intuitively accessible interface through which transient or casual users can retrieve information or experience narrative. The same data collation and modelling process can also assist conservation professionals in their tasks. Criteria are discussed for determining when it is more appropriate to model rather than use photographic techniques in the light of the commonly expressed fear in conservation circles that vicarious presentations may dominate genuine historical experience. Developments are identified which may assist in improving ease of use and understanding by visitors on and off-site.
Bi-Decompositions of Multi-Valued Functions for Circuit Design and Data Mining Applications
Authors: Bernd Steinbach, Marek A. Perkowski, Christian Lang
Venue: Proceedings of the Twenty Ninth IEEE International Symposium on Multiple-Valued Logic (1999)

We present efficient algorithms for the bi-decomposition of arbitrary incompletely specified functions in variable-valued logic. Several special cases are discussed. The algorithms are especially applicable for Data Mining applications, because, in contrast to the general multi-valued approaches to function decomposition that decompose to arbitrary tables, we create a network from multi-valued two-input operators that are selected by the user. Such decompositions lead to decision rules that are easier to understand by humans.
A Cognitive Model of Decision Making: Chunking and the Radar Detection Task
Authors: Constantine P. Papageorgiou, Kathleen Carley
Venue:  (1993)

We present Radar-Soar, a model of a cognitive agent learning to classify aircraft as friendly, neutral, or hostile based on a discrete set of characteristics. This agent is built using the Soar cognitive architecture which has as one of its main features a powerful form of explanation-based learning called chunking. We show that the performance this agent exhibits is extremely high and surpasses that of a comparable agent that has previously been built.