ppxscal/embedding_network huggingface dataset:
Multiple dispatch as dispatch on Tuples
Authors: Gary T. Leavens, Todd D. Millstein
Venue: ACM SIGPLAN Notices (1998)

Many popular object-oriented programming languages, such as C++, Smalltalk-80, Java, and Eiffel, do not support multiple dispatch. Yet without multiple dispatch, programmers find it difficult to express binary methods and design patterns such as the "visitor" pattern. We describe a new, simple, and orthogonal way to add multimethods to single-dispatch object-oriented languages, without affecting existing code. The new mechanism also clarifies many differences between single and multiple dispatch.
Meaningful change detection in structured data
Authors: Sudarshan S. Chawathe, Hector Garcia-Molina
Venue: Proceedings of the 1997 ACM SIGMOD international conference on Management of data (1997)

Detecting changes by comparing data snapshots is an important requirement for difference queries, active databases, and version and configuration management. In this paper we focus on detecting meaningful changes in hierarchically structured data, such as nested-object data. This problem is much more challenging than the corresponding one for relational or flat-file data. In order to describe changes better, we base our work not just on the traditional &ldquo;atomic&rdquo; insert, delete, update operations, but also on operations that move an entire sub-tree of nodes, and that copy an entire sub-tree. These operations allows us to describe changes in a semantically more meaningful way. Since this change detection problem is NP-hard, in this paper we present a heuristic change detection algorithm that yields close to &ldquo;minimal&rdquo; descriptions of the changes, and that has fewer restrictions than previous algorithms. Our algorithm is based on transforming the change detection problem to a problem of computing a minimum-cost edge cover of a bipartite graph. We study the quality of the solution produced by our algorithm, as well as the running time, both analytically and experimentally.
On-Line Fingerprint Verification
Authors: Anil Jain, Lin Hong, Ruud Bolle
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1997)

Fingerprint verification is one of the most reliable personal identification methods. However, manual fingerprint verification is so tedious, time-consuming, and expensive that it is incapable of meeting today's increasing performance requirements. An automatic fingerprint identification system (AFIS) is widely needed. It plays a very important role in forensic and civilian applications such as criminal identification, access control, and ATM card verification. This paper describes the design and implementation of an on-line fingerprint verification system which operates in two stages: minutia extraction and minutia matching. An improved version of the minutia extraction algorithm proposed by Ratha et al., which is much faster and more reliable, is implemented for extracting features from an input fingerprint image captured with an on-line inkless scanner. For minutia matching, an alignment-based elastic matching algorithm has been developed. This algorithm is capable of finding the correspondences between minutiae in the input image and the stored template without resorting to exhaustive search and has the ability of adaptively compensating for the nonlinear deformations and inexact pose transformations between fingerprints. The system has been tested on two sets of fingerprint images captured with inkless scanners. The verification accuracy is found to be acceptable. Typically, a complete fingerprint verification procedure takes, on an average, about eight seconds on a SPARC 20 workstation. These experimental results show that our system meets the response time requirements of on-line verification with high accuracy.
Lazy computation with exact real numbers
Authors: Abbas Edalat, Peter John Potts, Philipp Sünderhauf
Venue: Proceedings of the third ACM SIGPLAN international conference on Functional programming (1998)

We provide a semantical framework for exact real arithmetic using linear fractional transformations on the extended real line. We present an extension of PCF with a real type which introduces an eventually breadth-first strategy for lazy evaluation of exact real numbers. In this language, we present the constant redundant if, rif, for defining functions by cases which, in contrast to parallel if (pif), overcomes the problem of undecidability of comparison of real numbers in finite time. We use the upper space of the one-point compactification of the real line to develop a denotational semantics for the lazy evaluation of real programs. Finally two adequacy results are proved, one for programs containing rif and one for those not containing it. Our adequacy results in particular provide the proof of correctness of algorithms for computation of single-valued elementary functions.
On Projective Invariant Smoothing and Evolutions of PlanarCurves and Polygons
Authors: Alfred M. Bruckstein, Doron Shaked
Venue: Journal of Mathematical Imaging and Vision (1997)

Several recently introduced and studied planar curve evolution equations turn out to be iterative smoothing procedures that are invariant under the actions of the Euclidean and affine groups of continuous transformations. This paper discusses possible ways to extend these results to the projective group of transformations. Invariant polygon evolutions are also investigated.
Connection closures adding application-defined behaviour to network connections
Authors: S. Rooney
Venue: ACM SIGCOMM Computer Communication Review (1997)

New techniques in the implementation of out-of-band control in ATM networks are causing both industry and research laboratories to look again at the whole question of ATM signalling. These techniques devolve the control from the network devices into a higher level distributed processing environment, resulting in simpler network devices and more flexible control architectures.This paper takes this idea one stage further and suggests that at least in some cases, the only place in which control can be exerted without inhibiting applications is within the applications themselves. We call the combination of an application defined control policy and a network connection a connection closure.
Elastodynamics on clustered vector multiprocessors
Authors: V. Zecca, A. Kamel
Venue: ACM SIGARCH Computer Architecture News (1990)

We present the parallelization of an elastodynamic code on a firmly coupled configuration consisting of two IBM 3090-600 VF, a total of 12 processors, joined with a connection facility. The programming environment used is Clustered FORTRAN which is a facility for writing and executing parallel programs on two coupled IBM 3090 vector multiprocessors (VMP). Clustered FORTRAN provides extensions to FORTRAN so that a single application program can execute across multiple 3090 systems as well as across the processors of a single 3090 system. To exploit parallelism on each VMP, we used the parallel DO LOOP construct and to exploit parallelism across VMP we used the SCHEDULE statement allowing concurrent execution of subprograms. It is shown that such a problem, characterized by sufficiently large amounts of arithmetic operations within the parallel tasks, can be efficiently parallelized obtaining average speed-ups of more than five on one 3090-600 VF and nearly ten on a two 3090-600 VF cluster with a small programming effort.
Selecting the Optimal Focus Measure for Autofocusing and Depth-From-Focus
Authors: Murali Subbarao, Jenn-Kwei Tyan
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1998)

A method is described for selecting the optimal focus measure with respect to gray-level noise from a given set of focus measures in passive autofocusing and depth-from-focus applications. The method is based on two new metrics that have been defined for estimating the noise-sensitivity of different focus measures. The first metric¿the Autofocusing Uncertainty Measure (AUM)¿is useful in understanding the relation between gray-level noise and the resulting error in lens position for autofocusing. The second metric¿Autofocusing Root-Mean-Square Error (ARMS error)¿is an improved metric closely related to AUM. AUM and ARMS error metrics are based on a theoretical noise sensitivity analysis of focus measures, and they are related by a monotonic expression. The theoretical results are validated by actual and simulation experiments. For a given camera, the optimally accurate focus measure may change from one object to the other depending on their focused images. Therefore, selecting the optimal focus measure from a given set involves computing all focus measures in the set.
Equidistribution on the Sphere
Authors: Jianjun Cui, Willi Freeden
Venue: SIAM Journal on Scientific Computing (1997)

A concept of generalized discrepancy, which involves pseudodifferential operators to give a criterion of equidistributed pointsets, is developed on the sphere. A simply structured formula in terms of elementary functions is established for the computation of the generalized discrepancy. With the help of this formula five kinds of point systems on the sphere, namely lattices in polar coordinates, transformed two-dimensional sequences, rotations on the sphere, triangulations, and "sum of three squares sequence," are investigated. Quantitative tests are done, and the results are compared with one another. Our calculations exhibit different orders of convergence of the generalized discrepancy for different types of point systems.
Unimodality of Differences of Specialized Schur Functions
Authors: V. Reiner, D. Stanton
Venue: Journal of Algebraic Combinatorics: An International Journal (1998)

The centered difference of principally specialized Schur functions s_&tilde;&lambda;(1,q,....,q^n) - q<math>^ns_&lambda;(1,q,....,q^n) is shown to be a symmetric, unimodal polynomial in q with non-negative coefficients for certain choices of &tilde;&lambda;, &lambda;, and n, in which &tilde;&lambda; is always obtained from &lambda; by adding two cells, and n is chosen to be odd or even depending on &tilde;&lambda;, &lambda;. The basic technique is to find an injection of representations for the symplectic or orthogonal Lie algebras, and interpret the above difference as the principal specialization of the formal character of the quotient. As a special case, a difference of q-binomial coefficients is shown to be unimodal.
A note on &ldquo;On the conversion of indirect to direct recursion&rdquo;
Authors: Ting Yu, Owen Kaser
Venue: ACM Transactions on Programming Languages and Systems (TOPLAS) (1997)

In the article &ldquo;On the Conversion of Indirect to Direct Recursion&rdquo;(ACM Lett. Program. Lang. 2, 1-4. pp. 151-164), a method was introduced to convert indirect to direct recursion. It was claimed that for any call graph, there is a mutual-recursion elimination sequence if and only if no strongly connected component contains two node-disjoint circuits. We first give a counterexample and then provide a correction.
Efficient state-independent sequencing rules for certain flexible manufacturing systems
Authors: Arne Thesen
Venue: Proceedings of the 28th conference on Winter simulation (1996)

We introduce three state-independent methods for sequencing production of parts with random processing times on a simple production system such that productivity is maximized. The system of interest is one where parts of several different types are first processed on a common machine after which they proceed to separate, type-specific production lines. Referred to as random, rotation, and most-behind the rules are all based on easily computed estimates of the optimal product mix for the given part routings. Extensions of these rules are shown to give close to optimal performance in the case where blocking is present. The rules differs from conventional sequencing heuristics in that their performance is excellent over a wide range of system parameter values. The rules differ from optimal, state-dependent, scheduling rules in that no rule base or information about the current system states is needed.
Optimizing designs containing black boxes
Authors: Tai-Hung Liu, Khurram Sajid, Adnam Aziz, Vigyan Singhal
Venue: Proceedings of the 34th annual Design Automation Conference (1997)

We define a notion of equivalence for designs containingblack boxes i.e., components whose functionality is notknown; these arise naturally in the course of hierarchicaldesign. Using this notion, we describe a sound andcomplete methodology for optimizing such designs.
ADI Methods for Cubic Spline Collocation Discretizations of Elliptic PDE
Authors: P. Tsompanopoulou, E. Vavalis
Venue: SIAM Journal on Scientific Computing (1998)

This paper presents the formulation, analysis, and implementation of alternating direction implicit (ADI) methods for solving the linear system of algebraic equations that arise from the discretization of multidimensional linear elliptic partial differential equations (PDEs). The theoretical analysis is carried out for a broad class of PDE problems. Numerical experiments confirm the theoretically determined characteristics of the ADI iterative schemes. The computational effectiveness of the proposed schemes is shown through a detailed theoretical complexity analysis confirmed with our experimental data.
Hierarchical random simulation approach for the verification of S/390 CMOS multiprocessors
Authors: Jörg Walter, Jens Leenstra, Gerhard Döttling, Bernd Leppla, Hans-Jürgen Münster, Kevin Kark, Bruce Wile
Venue: Proceedings of the 34th annual Design Automation Conference (1997)

In this paper an approach is presented for thehierarchical verification of the memory control units, I/O adaptersand processor interconnect units as found in multiprocessorcomputer systems. It is shown how such units could be verifiedbetter and faster by the introduction of random executable timingdiagrams and associated CAD tool support. Furthermore, itis shown how the timing diagrams for the unit network verificationare easily derived from the timing diagrams specified for theunits. The multiprocessor hardware test showed the effectivenessof the proposed verification approach.
AMULET1: An Asynchronous ARM Microprocessor
Authors: J. Viv Woods, Steve B. Furber, Jim D. Garside, Steve Temple, Paul Day, Nigel C. Paver
Venue: IEEE Transactions on Computers (1997)

An asynchronous implementation of the ARM microprocessor has been developed using an approach based on Sutherland's Micropipelines [1]. The design allows considerable internal asynchronous concurrency. This paper presents the rationale for the work, the organization of the chip, and the characteristics of the prototype silicon. The design displays unusual properties such as nondeterministic (but bounded) prefetch depth beyond a branch instruction, a data dependent throughput, and employs a novel register locking mechanism. This work demonstrates the feasibility of building complex asynchronous systems and gives an indication of the costs and benefits of the Micropipeline approach.
Introduction to manufacturing applications
Authors: Gordon M. Clark
Venue: Proceedings of the 28th conference on Winter simulation (1996)

This tutorial introduces manufacturing applications of simulation through four illustrative example applications. These examples illustrate the additional understanding of system behavior gained by the use of simulation models. Individuals using simulation should use a structured process in applying simulation. The second example illustrates this structured process. The examples also illustrate the use of both stochastic and deterministic variables in modeling manufacturing systems.
q-Series Arising From The Study of Random Graphs
Authors: George E. Andrews, Davide Crippa, Klaus Simon
Venue: SIAM Journal on Discrete Mathematics (1997)

This paper deals with q-series arising from the study of the transitive closure problem in random acyclic digraphs. In particular, it presents an identity involving divisor generating functions which allows us to determine the asymptotic behavior of polynomials defined by a general class of recursive equations, including the polynomials for the mean and the variance of the size of the transitive closure in random acyclic digraphs.
Impact of task duplication on static-scheduling performance in multiprocessor systems with variable execution-time tasks
Authors: Emilio Luque, Ana Ripoll, Porfidio Hernández, Tomás Margalef
Venue: ACM SIGARCH Computer Architecture News (1990)

The problem of scheduling a set of partially ordered tasks on a nonpreemptive multiprocessor system of identical processors assuming that the execution time of some tasks can vary within a set of known values is studied in an effort to construct a more realistic static schedule. A new heuristic algorithm (CP/MISF/TD) based on task duplication is proposed. The effectiveness of the algorithm is proved by comparing the results obtained for a wide variety of task graphs with the ones obtained by applying the classical list scheduling algorithms which consider fixed time tasks. Keywords: Static scheduling, List scheduling, Heuristic algorithms, Task duplication, Multiprocessor systems.
Quantitative Information of Specific Diagnostic Tests
Authors: Allen F. Bowyer
Venue: Journal of Medical Systems (1998)

The goal of diagnostic testing is to maximize information (I) of a specific disease of interest (D) resulting from the performance of a specific diagnostic test procedure (T). However, all tests suffer from errors which result in incomplete information and inaccurate diagnostic conclusions. The methods of Information Theory have successfully solved a range of signal transmission problems involving physical systems operating under conditions of noise. Medical testing procedures were found to be analogous to noisy systems&semi; hence, Information Theory methods were applied to minimize errors in diagnostic testing. Prior to performing a diagnostic test, the quantity of information, Apriori Information (ID), regarding the presence or absence of the disease was only a function of the prevalence (P) of disease in the population. After performing a diagnostic test, the quantity of information, Aposteriori Information (IDIT) was a function of not only P but also the test sensitivity (A) and test specificity (B). The quantity of information gained by test performance was computed from the difference between aposteriori and apriori information. \Delta {\rm I}={\rm I_{\rm DIT}-I_D} To illustrate the relationship between pretest, apriori, and post-test, aposteriori, information the values ID and IDIT were computed for five common cardiovascular tests applied to populations with different coronary artery disease prevalence. This cross-sectional analysis studied the quantitative information obtained from Electrocardiography (ECG), Bicycle Ergometer Stress Tests (BEST), Stress-Echo Ergometer Tests (SEET), Thallium 201 Stress Tests (ThST), and Coronary Arteriography (CorA). Apriori information ranged from a minimum of 0 (for prevalence &equals; 0.5) to a maximum of 1.0 (for prevalence &equals; 0 or 1.0) The aposteriori information was computed for all apriori information and occupied the range between that of a &ldquo;perfect&rdquo; test (A &equals; 1.0 and B &equals; 1.0) and that of a &ldquo;worthless&rdquo; test (A &equals; 0.5 and B &equals; 0.5). All tests demonstrated greater information gain when apriori information was minimal&semi; Little additional information could be gained when the apriori information was close to certainty (i.e., for prevalence near 0 or 1.0). Electrocardiography demonstrated little significant IDIT at any value of ID. Thallium 201 stress tests provided similar aposteriori information values to those of Stress-Echo Ergometer Stress and either demonstrated greater information gain than Bicycle Ergometer Stress Tests. Coronary Arteriography provided the maximum values of aposteriori information. Information Theory methods provided an effective quantitative method to compare the effectiveness of diagnostic tests over a wide range of disease prevalence.
On the development of a computer system to simulate port operations considering priorities
Authors: José Holguín-Veras, C. Michael Walton
Venue: Proceedings of the 28th conference on Winter simulation (1996)

This paper describes the simulation system developed at The University of Texas at Austin for the performance analysis of port operations considering container's priority. The paper discusses the current trends toward service differentiation and provides a brief description of port operations and the historical evolution of performance analysis in this area. The conceptual and computational characteristics of the simulation system are described, as well as the calibration process. Finally, conclusions and recommendations for further research are discussed.
Initial Results for Glacial Variable Analysis
Authors: Tito Autrey, Michael Wolfe
Venue: International Journal of Parallel Programming (1998)

Runtime code generation that uses the values of one or more variables to generate specialized code is called value-specific optimization. Typically, value-specific optimization focuses on variables that are modified much less frequently than they are referenced; we call these glacial variables. In current systems that use runtime code generation, glacial variables are identified by programmer directives. Next, we describe glacial variable analysis, the first data-flow analysis for automatically identifying glacial variables. We introduce the term staging analysis to describe analyses that divide a program into stages or use the stage structure of a program. Glacial variable analysis is an interprocedural staging analysis that identifies the relative modification and reference frequencies for each variable and expression. Later, several experiments are given to characterize a set of benchmark programs with respect to their stage structure, and we show how often value-specific optimization might be applied. Finally, we explain how staging analysis relates to runtime code generation, briefly describe glacial variable analysis and present some initial results.
The Ada recommendation&mdash;a year later
Authors: Rayford B. Vaughn,  Jr.
Venue: ACM SIGAda Ada Letters (1998)

In January 1997, the National Research Council published a report to the Department of Defense entitled Ada and Beyond, Software Policies for the Department of Defense. The author of this paper was a member of the committee that produced that report. This paper looks at the original recommendations of the report and comments on the results (intended and unintended) within the DoD community over the past year.
Fast and Exact Simulation of Stationary Gaussian Processes through Circulant Embedding of the Covariance Matrix
Authors: C. R. Dietrich, G. N. Newsam
Venue: SIAM Journal on Scientific Computing (1997)

Geostatistical simulations often require the generation of numerous realizations of a stationary Gaussian process over a regularly meshed sample grid $\Omega$. This paper shows that for many important correlation functions in geostatistics, realizations of the associated process over $m+1$ equispaced points on a line can be produced at the cost of an initial FFT of length $2m$ with each new realization requiring an additional FFT of the same length. In particular, the paper first notes that if an $(m+1)\times(m+1) $ Toeplitz correlation matrix $R$ can be embedded in a nonnegative definite $2M\times2M$ circulant matrix $S$, exact realizations of the normal multivariate $y \sim {\cal N}(0,R)$ can be generated via FFTs of length $2M$. Theoretical results are then presented to demonstrate that for many commonly used correlation structures the minimal embedding in which $M = m$ is nonnegative definite. Extensions to simulations of stationary fields in higher dimensions are also provided and illustrated.