ppxscal/embedding_network huggingface dataset:
Moving Objects Classification in a Domestic Environment using Quadratic Neural Networks
Authors: Sok G Lim, Mike Alder, Christopher J.S. deSilva, Yianni Attikiouzel
Venue:  (1994)

In this paper, we outline a moving object recognition system. A description is given of the whole system from the image acquisition through the preprocessing and feature extraction stages to the classification of objects. We use Quadratic Neural Networks (QNN) to model the input data and then extract features from the model which are translation and rotation invariant. We have applied the idea to a practical problem of classifying moving objects in a domestic environment such as a moving heads, curtains blown by the wind and external events such as moving tree branches. Reasonable results are obtained using only the spatial information.
Automating Physical Reorganizational Requirements at the Access Path Level of a Relational Database System
Authors: Weddell Grant Edwin
Venue:  (1980)

Any design of an access path level of a database management system must make allowance for physical reorganization requirements. The facilities provided for such requirements at the access path level have so far been primitive in nature (almost always, in fact, requiring complicated human intervention). This thesis begins to explore the notion of increasing the degree of automation of such requirements at the access path level; to consider the practical basis for self-adapting or self-organizing data management systems. Consideration is first given to the motivation (justification) of such a notion. Then, based on a review of the relevent aspects of a number of existing data management systems, we present a complete design specification and outline for a proposed access path level. Regarding this system we consider in detail the automation of two major aspects of physical organization: the clustering of records on mass storage media and the selection of secondary indices. The results of our analysis of these problems provides a basis for the ultimate demonstration of feasibility of such automation. 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
Finitely Representable Databases
Authors: Stephane Grumbach, Jianwen Su
Venue:  (1995)

We study classes of infinite but finitely representable databases based on constraints, motivated by new database applications such as geographical databases. We formally define these notions and introduce the concept of query which generalizes queries over classical relational databases. We prove that in this context the basic properties of queries (satisfiability, containment, equivalence, etc.) are nonrecursive. We investigate the theory of finitely representable models and prove that it differs strongly from both classical model theory and finite model theory. In particular, we show that most of the well known theorems of either one fail (compactness, completeness, locality, 0/1 laws, etc.). An immediate consequence is the lack of tools to consider the definability of queries in the relational calculus over finitely representable databases. We illustrate this very challenging problem through classical examples. We then mainly concentrate on dense order databases, and exhibit some new techniques to prove non first-order definability results. The techniques include complexity theoretical arguments and Ehrenfueucht-Fraisse games. In particular, we show that queries over finite relations such as parity and graph connectivity, as well as topological queries such as region connectivity, existence of a hole, Eulerian traversal, homeomorphism, etc. are not first-order definable. We also show that inflationary Datalog with negation captures exactly all dense order queries computable in PTIME.
Automatic Verification of Asynchronous Circuits
Authors: Trevor W. S. Lee, Mark R. Greenstreet, Carl Seger
Venue:  (1993)

Asynchronous circuits are often used in interface circuitry where traditional, synchronous design methods are not applicable. However, the verification of asynchronous designs is difficult, because standard simulation techniques will often fail to reveal design errors that are only manifested under rare circumstances. In this paper, we show how asynchronous designs can be modeled as programs in the Synchronized Transitions language, and how this representation facilitates rigorous and efficient verification of the designs using ordered binary diagrams (OBDDs). We illustrate our approach with two examples: a novel design of a transition arbiter and a design of a toggle element from the literature. The arbiter design was derived by correcting an error in an earlier attempt. It is noteworthy that the error in the original design, found very quickly using the methods described in this paper, went unnoticed during more than 50 hours of CPU time simulation 2^31 state transitions.
The Pagenumber of k-Trees is 0(k)
Authors: Joseph L. Ganley, Lenwood S. Heath
Venue:  (1995)

A k-tree is a graph defined inductively in the following way: the complete graph K(sub-k) is a K-tree, and if G is a k-tree, then the graph resulting from adding a new vertex to k vertices inducing a K(sub-k) in G is also a k-tree. This paper examines the book embedding problem for k-trees. A book embedding of a graph maps the vertices onto a line along the spine of the book and assigns the edges to pages of the book such that no two edges on the same page cross. The pagenumber of a graph is the minimum number of pages in a valid book embedding. In this paper, it is proven that the pagenumber of a k-tree is at most k + 1. Furthermore, it is shown that there exist k-trees that require k pages. The upper bound leads to bounds on the pagenumber of a variety of classes of graphs for which no bounds were previously known.
Algebraic Methods in Prolog Programming
Authors: Sergio Antoy
Venue:  (1989)

We discuss some difficulties of coding and invoking functions implemented by predicates and we propose a number of conceptual tools for overcoming these difficulties. We use an algebraic model which supports strategies for designing complete, parsimonious, and terminating functions. We describe a translation scheme for converting these functions into predicates and we prove a number of properties of this transformation. Our investigation provides an algebraic interpretation of the cut and raises two issues of lack of orthogonality in the Prolog programming languages. We outline practical tools, based on our ideas, which simplify substantially some significant steps of the design and use of certain Prolog predicates. We extend current work on the translation from algebraic specifications and term rewriting systems to logic programs along two
LOW-COMPLEXITY SUBBAND CODING FOR IMAGE COMPRESSION(Ph.D. Dissertation Proposal)
Authors: Don Speck
Venue:  (1994)

Subband coding compresses grayscale still images of natural scenes by quantization and entropy coding of critically subsampled spatial frequency bands. A specially-designed multi-channel spectral analysis filterbank splits the bandwidth in such a way that a matched synthesis filterbank can exactly reconstruct the original image from the unquantized subbands and, from the quantized subbands, recover the image with distortion little or no worse than quantizing the image directly. With no change in the total sample count, compression to less than 1 bit/pixel comes from entropy coding of high-frequency channels, which quantize to almost all zeroes, due to the subband transformation packing most of the energy into the low-frequency channel and allowing quantization to be perceptually weighted by spatial frequency. FIR filterbanks are obvious candidates for parallel, pipelined VLSI implementation. Acceptance has been held back primarily by the computational expense of high-quality FIR filters and the lack of standardization. This Dissertation Proposal addresses both issues with a way of reducing the number of additions and multiplications for certain linear-phase exact-reconstruction two-channel filterbanks, constructed for this formulation gave better rate-distortion than any fo the Daubechies maximally-flat wavelet filters, yet the simplest requires only 6 additions and 2 shifts per pair of samples; including its modification at the image boundaries, its implementation in C is only 8 lines.
Elektra: A Reflective Production System
Authors: I. D. Craig
Venue:  (1991)

This paper provides an overview of the ELEKTRA production rule interpreter. Although of an outwardly traditional nature, ELEKTRA differs from other interpreters by providing considerable support for meta -level inference. The paper describes the representions employed in the system, together with the interface to user-defined code. It also describes ways in which control problem in production systems can be solved by increasing use of rules. Finally, the reflective properties of the system are introduced and examples are given. These examples centre round the ability of ELEKTRA to encode and to model rule interpreters of different kinds. It is shown that an interpreter on which the entire ELEKTRA system runs can be implemented as ELEKTRA rules. It is also shown that any rule interpreter which is written in the form of ELEKTRA rules can be interpreted by itself.
Deriving Optical flow in Noisy Image Sequences
Authors: W. B. Goh, G. R. Martin
Venue:  (1991)

A technique is presented extracting local image motion utilising the properties of spatiotemporal orientation i n the frequency domain. This technique is based on the eigenvalue analysis of the inertia tensor matrix of the frequency domain. An iterative velocity field smoothing algorithm was developed based on the properties of a variant of this inertia tensor matrix. This iterative algorithm is able to smooth noisy translational, rotational and other smoothly varying velocity flow fields, within the constraints of motion discontinuities. Some results from the application of this algorithm to noisy random dot sequences are presented.
A Computational Theory of Decision Networks
Authors: Nevin L Zhang, Runping Qi, David Poole
Venue:  (1993)

Decision trees (Raiffa 1968) are the first paradigm where an agent can deal with multiple decisions. The non-forgetting influence diagram formalism (Howard and Matheson 1983, Shachter 1986) improves decision trees by exploiting random variables'' independencies of decision variables and other random variables. In this paper, we introduce a notion of decision networks that further explore decision variables'' independencies of random variables and other decision variables. We also drop the semantic constraints of total ordering of decisions and of one value node. Only the fundamental constraint of acyclicity is kept. \par From a computational point of view, it is desirable if a decision network is stepwise-solvable, i.e if it can be evaluated by considering one decision at a time. However, decision network in the most general sense need not to be stepwise-solvable. A syntactic constraint called stepwise-decomposability is therefore imposed. We show that stepwise-decomposable decision networks can be evaluated not only by considering one decision at a time, but also by considering one portion of the network at a time.
Data mining in designing an agent-based DSS
Authors: Christian Böhm, María Rosa Galli, Omar Chiotti
Venue: Data mining: opportunities and challenges (2003)

The aim of this work is to present a data-mining application to software engineering. Particularly, we describe the use of data mining in different parts of the design process of an agent-based architecture for a dynamic decision-support system. The work is organized as follows: An introduction section defines the characteristics of a dynamic decision-support system and gives a brief background about the use of data mining and case-based reasoning in software engineering. A second section describes the use of data mining in designing the system knowledge bases. A third section presents the use of data mining in designing the learning process of the dynamic decision-support system. Finally, a fourth section describes the agent-based architecture we propose for the dynamic decision support system. It implements the mechanisms designed by using data mining to satisfy the system functionality.
Towards Structured Parallel Computing --- Part 1 --- A Theory of Algorithm Design and Analysis for Distributed-Memory Architectures
Authors: Feng Gao
Venue:  (1989)

This paper advocates a architecture-independent, hierarchical approach to algorithm design and analysis for distributed-memory architectures, in contrast to the current trend of tailoring algorithms towards specific architectures. We show that, rather surprisingly, this new approach can achieve uniformity without sacrificing optimality. In our particular framework there are three levels of algorithm design: design of a network-independent algorithm in a network-independent programming environment, design of virtual architectures for the algorithm, and design of emulations of the virtual architectures on physical architectures. We propose and substantiate through a complete complexity analysis of the example of ordinary matrix multiplication, the following thesis: architecture-independent optimality can lead to portable optimality. Namely, a single network-independent algorithm, when optimized network-independently, with the support of properly chosen virtual architectures, can be implemented on a wide spectrum of networks to achieve optimality on each of them with respect to both computation and communication. Besides its implications to the methodology of parallel algorithm design, our theory also suggests new questions for theoretical research in parallel computation on interconnection networks.
Improved Linux File System Hashing
Authors: Ying Chen, Walter Burkhard, John Palmer
Venue:  (2001)

The Linux kernel utilizes caches to speed up accesses to the high-usage objects that are normally stored on disks, such as data cache pages for files, inodes, and directory entries. These cache data types are implemented using separate chaining. In our experience, we found that some of the hash functions used in th circa 2000 Linux kernel can results, for certain access patterns, in very skewed data distributions over the chains. Better hash functions are desirable. In this paper, we analyze the data distribution and run-time efficiencies of a set of hash function for Linux inode and directory caches. Our analysis utilizes data traces from both an industry standard benchmark and two real world computing environments. Although some of the results were anticipated by Lever, who has carried out a similar study, we show that his results can be further improved.
Software Quality Measurement: Assessment, Prediction and Validation
Authors: Richard E. Nance, James D. Arthur
Venue:  (1994)

Research addressing three challenging problems is described: (1) software quality assessment, (2) software quality prediction, and (3) the validation of both capabilities. The three are the focus of an empirical investigation conducted by a university research team using a development project by a Navy contractor as a laboratory. The predominantly Ada implementation total over 100,000 lines of source code, with approximately 40,000 included in this study. Using a procedure that couples two fundamental concepts: the Objectives/Principles/Attributes framework with software quality indicators, this longitudinal research project represents the most comprehensive effort yet to validate an approach to assessing software quality. Additionally, the more challenging problem of predicting software quality is tackled through an extraction and analysis of both process and product characteristics. Automated tools applied to both programs and documentation are described in the context of their contributing roles in measurement. Sources of difficulty in automating the assessment are identified. The basis for statistical validation are described, and anticipated hypotheses are examined. 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
Parallel Cost Analysis of Adaptive GMRES Implementations for Homotopy Methods
Authors: Sosonkina Maria, Allison Donald C.S., Watson Layne T.
Venue:  (1997)

The success of homotopy methods in solving large-scale optimization problems and nonlinear systems of equations depends heavily on the solution of large sparse nonsymmetric linear systems on parallel architectures. Iterative solution techniques, such as GMRES(k), favor parallel implementations. However, their straightforward parallelization usually leads to a poor parallel performance because of global communication incurred by processors. One variation on GMRES(k) considered here is to adapt the restart value k for any given problem and use Householder reflections in the orthogonalization phase to achieve high accuracy and to reduce the communication overhead. The Householder transformations can be performed without global communications and modified to utilize an arbitrary row distribution of the coefficient matrix. The effect of this modification on the GMRES(k) performance is discussed here, as well as the abilities of parallel GMRES implementations using Householder reflections to maintain fixed efficiency with increase in problem size and number of processors. Theoretical communication cost and isoefficiency analyses are compared with experimental results on an Intel Paragon, Gray T3E, and IBM SP2.
Low Stretch Spanning Trees for Planar Graphs,
Authors: D. Peleg, D. Tendler
Venue:  (2001)

This paper considers the problem of selecting a low stretch spanning tree for a given planar graph. The stretch of the tree T over a vertex pair u,w is defined as the ratio between the distance from u to w in T and their distance in the original graph. Two central problems that arise regarding the worst-case and average stretch are (1) the minimum stretch spanning tree (MSST) problem, introduced in [CC95], which asks for finding a spanning tree minimizing the maximum stretch over all vertex pairs, and (2) the minimum average stretch spanning tree (MAST) problem, introduced in [AKPW95]. Dealing with t-spanner trees, it is shown in [FK98] that even for unweighted planar graph it is NP-hard to determine the optimal maximum stretch. This paper focuses on the MSST and MAST problems on unweighted planar graphs. It is shown that both problems can be solved exactly in polynomial time on outerplanar graphs, and also in the special case of 1-face depth graphs in which no interior vertex has degree 2. Then, a 2k-approximation algorithm is proposed for the MAST problem on general planar graphs, where k is the face depth of the graph.
Definite Clause Translation Grammars
Authors: Harvey Abramson
Venue:  (1984)

In this paper we introduce Definite Clause Translation Grammars, a new class of logic grammars which generalizes Definite Clause Grammars and which may be thought of as a logical implementation of Attribute Grammars. Definite Clause Translation Grammars permit the specification of the syntax and semantics of a language: the syntax is specified as in Definite Clause Grammars; but the semantics is specified by one or more semantic rules in the form of Horn clauses attached to each node of the parse tree (automatically created during syntactic analysis), and which control traversal(s) of the parse tree and computation of attributes of each node. The semantic rules attached to a node constitute therefore, a local data base for that node. The separation of syntactic and semantic rules is intended to promote modularity, simplicity and clarity of definition, and ease of modification as compared to Definite Clause Grammars, Metamorphosis Grammars, and Restriction Grammars.
Optimal Algorithms for Probalistic Solitude Detection On Anomymous Rings
Authors: Karl Abrahamson, Andrew Adler, Lisa Higham, David G. Kirkpatrick
Venue:  (1990)

Probabilistic algorithms that err with probability at most $\epsilon \geq 0$ are developed for the Solitude Detection problem on anonymous asynchronous unidirectional rings. Solitude Detection requires that a nonempty set of distinguished processors determine whether or not there is only one distinguished processor. The algorithms transmit an optimal expected number of bits, to within a constant factor. Las Vegas and Monte Carlo algorithms that terminate both distributively and nondistributively are developed. Their bit complexities display a surprisingly rich dependence on the kind of algorithm and on the processors'' knowledge of the size of the ring.
Scalable Causal Message Logging for Wide-Area Environments
Authors: Karan Bhatia, Keith Marzullo, Lorenzo Alvisi
Venue:  (2001)

Wide-area systems are gaining in popularity as an infrastructure for running scientific applications. From a fault tolerance perspective, these environments are challenging due to their scale and their inherent variability. Causal message logging protocols have attractive properties that make them suitable for these environments. They spread fault tolerance information around in the system providing high availability. This information can also be used to replicate objects that are otherwise inaccessible due to network partitions. However, current causal message logging protocols do not scale to thousands or millions of processes. We describe the Hierarchical Causal Logging Protocol (HCML) that uses a hierarchy of shared logging sites, or {\em proxies}, to reduces the space requirements exponentially. These proxies also act as caches for fault tolerance information and reduce the overall message overhead of causal message logging protocols by as much as 50\%. In addition, HCML leverages differences in bandwidth between communicating processes by piggybacking more fault tolerance information over high bandwidth links. Doing so improves overall message latency by as much as 97\%.
PROVIDING PERFORMANCE GUARANTEES IN AN FDDI NETWORK
Authors: Darrell D.E. Long, Carol Osterbrock, Luis Cabrera
Venue:  (1993)

A network subsystem supporting a continuous media file system must guarantee a minimum, throughput, a maximum delay, and a maximum jitter. We present a transport protocol that provides these guarantees. To support different types of service, our protocol is built from modules selected to meet the requirements of each communications session. A buffering technique is used to provide jitter guarantees. To provide throughput and delay guarantees, network performance is optimized based on the required transfer rate. The effects of controlling transmission rate and packet size are presented. The resulting transport protocol is modeled on a simulated FDDI network and the results are analyzed. We show that the protocol provides the required guarantees for the anticipated types of traffic.