ppxscal/embedding_network huggingface dataset:
Reliable On-Line Human Signature Verification Systems
Authors: Luan L. Lee, Toby Berger, Erez Aviczer
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1996)

On-line dynamic signature verification systems were designed and tested. A data base of more than 10,000 signatures in (x(t), y(t))-form was acquired using a graphics tablet. We extracted a 42-parameter feature set at first, and advanced to a set of 49 normalized features that tolerate inconsistencies in genuine signatures while retaining the power to discriminate against forgeries. We studied algorithms for selecting and perhaps orthogonalizing features in accordance with the availability of training data and the level of system complexity. For decision making we studied several classifiers types. A modified version of our majority classifier yielded 2.5% equal error rate and, more importantly, an asymptotic performance of 7% false acceptance rate at zero false rejection rate, was robust to the speed of genuine signatures, and used only 15 parameter features.
On the use of VHDL-based behavioral synthesis for telecom ASIC design
Authors: Mark Genoe, Paul Vanoostende, Geert van Wauwe
Venue: Proceedings of the 8th international symposium on System synthesis (1995)

Abstract: VHDL-based behavioral synthesis is appearing on the market but it still has to prove that it can have a significant impact. In the past, most applications for behavioral synthesis came from the DSP area and from the academic world. In contrast, this paper describes the results of an investigation and evaluation of several behavioral synthesis tools, carried out on recent designs of Alcatel-Bell, leading to a more detailed study of relevant industrial telecom non-DSP circuits, that were suitable for behavioral synthesis. From our expertise in telecom system hardware design, we can conclude that, taking into account that today world-wide about 6,000 licenses for logic synthesis are in use, there is distinctly a market potential for design-entries at higher levels of abstraction, due to the still increasing design complexities that can be expected in the near future. Behavioral synthesis can play a key role in this prospect, as stand-alone hardware CAD tool, or integrated in a global system design flow strategy for HW/SW-codesign. However, we experienced that efficient use of behavioral synthesis tools for telecom non-DSP circuits requires functionality that goes beyond simply generating an RTL-synthesizable description. This functionality is discussed, together with a system level design methodology for efficient use of behavioral synthesis tools.
Research directions in software reuse: where to go from here?
Authors: Harald Gall, Mehdi Jazayeri, René Klösch
Venue: ACM SIGSOFT Software Engineering Notes (1995)

Software reuse is no longer in its infancy. We are able to look back at more than 15 years of research and should use the opportunity of such a symposium to critically evaluate the past research in order to identify promising future research areas in software reuse.In this paper, we give a broader view of reuse and some of the so far less-considered areas, which we believe may support software reuse to get off the ground. We mention our ongoing research in software reuse, discussing reuse experiments in the areas of long-term software evolution and component programming.Furthermore, we indicate the critical importance of interactions among the reuse and related communities within software engineering, such as the object-oriented and the software maintenance communities.
Real time character scaling and rotation
Authors: David L. Andrews, Randy Brown, Charles Caldwell, Andrew Wheeler
Venue: ACM SIGAPP Applied Computing Review (1995)

This paper describes a real time signal processing subsystem used to perform character scaling and rotation. First, the algorithms used in the subsystem are described. The algorithms were developed for performing sorting decisions on mail for the USPS. The computational complexity of the algorithms implemented in the subsystem is then reviewed, and finally the implementation of the algorithms in discrete logic, DSP's, and FPGA's is discussed.
Middle East Technical University Software Research and Development Center
Authors: Asuman Dogac
Venue: ACM SIGMOD Record (1996)

Middle East Technical University (METU) is the leading technical university in Turkey. The Software Research and Development Center was established by the Scientific and Technical Research Council of Turkey (TUBITAK) at the Department of Computer Engineering of METU in October 1991. The aim of this center is twofold: to lead large scale software research and development projects, and to foster international cooperation. SRDC is involved in a number of research and development projects supported by the government, industrial companies and international organizations. Although SRDC projects also cover other fields of computer science, the main emphasis is on database systems. SRDC is organized around the ongoing projects and several engineers and graduate students work in these projects: M. Altinel, B. Arpinar, I. Cingil, Y. Ceken, C. Dengi, E. Gokkoca, C. Evrendilek, P. Karagoz, E. Kilic, P. Koksal, S. Mancuhan, S. Nural, F. Ozcan, G. Ozhan, V. Sadjadi, N. Tatbul. Its infrastructure includes a LAN with Sun Workstations and PCs and commercial software like Oracle7, Sybase, Informix, Adabas D, Ingres and DEC's ObjectBroker. SRDC is a beta test site for several products including SunSoft's Joe and Concerto and Orbix's Object Transaction Service. The remainder of this report describes the main projects.
Persistency of Excitation in Identification Using Radial Basis Function Approximants
Authors: A. J. Kurdila, Francis J. Narcowich, Joseph D. Ward
Venue: SIAM Journal on Control and Optimization (1995)

In this paper, identification algorithms whose convergence and rate of convergence hinge on the regressor vector being persistently exciting are discussed. It is then shown that if the regressor vector is constructed out of radial basis function approximants, it will be persistently exciting, provided a kind of "ergodic" condition is satisfied. In addition, bounds on parameters associated with the persistently exciting regressor vector are provided; these parameters are connected with both the convergence and rates of convergence of the algorithms involved.
Adoption of computer aided software engineering (CASE) technology: an innovation adoption perspective
Authors: G. Premkumar, Michael Potter
Venue: ACM SIGMIS Database (1995)

This study examines the impact of various organizational and technology characteristics on the adoption of computer aided software engineering (CASE) technology. Based on research in innovation adoption and IS implementation, the study develops a research model comprised of seven factors that are important for the successful adoption of CASE technology. The data for the study were collected through a field survey of IS managers in the midwest area and 90 responses were received. The results of discriminant analysis reveal that of the seven predictor variables, five are important to differentiate adopters from non-adopters. They are the existence of a product champion, strong top management support, lower IS expertise, perception that CASE technology has greater relative advantage over other alternatives, and a conviction of the cost effectiveness of the technology. The results are consistent with findings in innovation adoption literature as well as case studies of many firms' experience on CASE implementation.
Declustering of key-based partitioned signature files
Authors: Paolo Ciaccia, Paolo Tiberio, Pavel Zezula
Venue: ACM Transactions on Database Systems (TODS) (1996)

Access methods based on signature files can largely benefit from possibilities offered by parallel environments. To this end, an effective declustering strategy that would distribute signatures over a set of parallel independent disks has to be combined with a synergic clustering which is employed to avoid searching the whole signature file while executing a query. This article proposes two parallel signature file organizations, Hamming Filter (HF) and Hamming + Filter (H+F), whose common declustering strategy is based on error correcting codes, and where clustering is achieved by organizing signatures into fixed-size buckets, each containing signatures sharing the same key value. HF allocates signatures on disks in a static way and works well if a correct relationship holds between the parameters of the code and the size of the file. H+F is a generalization of HF suitable to manage highly dynamic files. It uses a dynamic declustering, obtained through a sequence of codes, and organizes a smooth migration of signatures between disks so that high performance levels are retained regardless of current file size. Theoretical analysis characterizes the best-case, expected, and worst-case behaviors of these organizations. Analytical results are verified by experiments on prototype systems.
Introduction&mdash;computing and social responsibilities
Authors: Douglas Schuler, Jonathan Jacky
Venue: Communications of the ACM (1989)

The three articles in this special section deal with computing applications that affect how people are treated in their social roles: as litigants, as employees, or as participants or bystanders in warfare. We believe that applications like these obligate their builders to consider their duties, not only to their employers or customers, but to all the people who will be affected when the systems are placed into service. These duties are the social responsibilities of computer professionals. Authors Donald erman and Carole Hafner address the social responsibility of creating a timely, affordable and just legal system. Jack Beusmans and K&auml;ren Wieckert address the social responsibilities of educators, researchers and applications programmers to consider whether their contributions to weapons technology are a positive contribution to society. Richard Ladner addresses responsibilities that society has for people with disabilities.
Architectural and protocol frameworks for multicast data transport in multi-service networks
Authors: K. Ravindran
Venue: ACM SIGCOMM Computer Communication Review (1996)

The paper presents architectural and protocol techniques for multicast transport of multi-service data (such as video, audio and graphics). A tree-structured channel in the network is employed as building block for constructing multicast transport services. Data from different sources are multiplexed over a shared tree channel for reaching destinations through intermediate network nodes and links. The choice of multicast architecture is based on the extent of sharing of common links in a tree across multi-source data flows to allow finer degree of link bandwidth allocation control and reduce the fixed cost of links for data transport. The canonical network substrate so constructed exemplifies a 'programmable network' that may be 'plugged-in' with QOS and flow parameters to instantiate the network behavior for matching the needs of each application. This philosophy is in alignment with the evolving 'Internet Service Layer' functionalities. The paper describes the functional and protocol elements of multicast architectures to support the 'programmable network' view. It also describes the salient features of an implementation embedding these architectures.
Computer skills in demand: what are Florida employers looking for?
Authors: Keith W. Rupert
Venue: 3C ON-LINE (1995)

A recently-completed class project shows that Florida employers seek employees with computer skills in software applications, WordPerfect, and Louts 1-2-3. It also shows a need for programmers in COBOL and C/C++, with a new niche for skills in Visual BASIC. Unix-based systems are shown to have a large foothold as well.
A Comparison of ID3 and Backpropagation for English Text-To-Speech Mapping
Authors: Thomas G. Dietterich, Hermann Hild, Ghulum Bakiri
Venue: Machine Learning (1995)

The performance of the error backpropagation (BP) and ID3 learning algorithms was compared on the task of mapping English text to phonemes and stresses. Under the distributed output code developed by Sejnowski and Rosenberg, it is shown that BP consistently out-performs ID3 on this task by several percentage points. Three hypotheses explaining this difference were explored: (a) ID3 is overfitting the training data, (b) BP is able to share hidden units across several output units and hence can learn the output units better, and (c) BP captures statistical information that ID3 does not. We conclude that only hypothesis (c) is correct. By augmenting ID3 with a simple statistical learning procedure, the performance of BP can be closely matched. More complex statistical procedures can improve the performance of both BP and ID3 substantially in this domain.
On the k-server conjecture
Authors: Elias Koutsoupias, Christos H. Papadimitriou
Venue: Journal of the ACM (JACM) (1995)

We prove that the work function algorithm for the k-server problem has a competitive ratio at most 2k&minus;1. Manasse et al. [1988] conjectured that the competitive ratio for the k-server problem is exactly k (it is trivially at least k); previously the best-known upper bound was exponential in k. Our proof involves three crucial ingredients: A quasiconvexity property of work functions, a duality lemma that uses quasiconvexity to characterize the configuration that achieve maximum increase of the work function, and a potential function that exploits the duality lemma.
CALOS: an experiment with computer-aided learning for operating systems
Authors: Murray W. Goldberg
Venue: ACM SIGCSE Bulletin (1996)

This paper describes CALOS, our application of computer-aided learning to a third-year Computer Science course in Operating Systems. The delivery tool we choose is the World Wide Web. The course material consists of interactive exercises, interactive simulations and demonstrations, on-line notes, student - instructor communication mechanisms, student - student communication mechanisms, progress tracking, navigational aids, student evaluations, a glossary and a bibliography. We make use of text, images, animations and voice. We plan to offer the course experimentally in several modes in order to determine the best use of the hypermedia presentation.
Processor Allocation in Hypercube Multiprocessors
Authors: Suresh Rai, Jerry L. Trahan, Thomas Smailus
Venue: IEEE Transactions on Parallel and Distributed Systems (1995)

The processor allocation problem requires recognizing and locating a free subcube that can accommodate a request for a subcube of a specified size for an incoming task. Methods reported in the literature fall into two strategies: Bottom-up or bit mapped technique (BMT) and top-down or available cube technique (ACT). Our algorithm that solves the allocation problem in faulty hypercubes falls into the category of ACT's which offer the advantage over BMT's of quickly recognizing whether or not a requested subcube is available in the list of fault-free subcubes. We introduce new algebraic functions and the concept of separation factor to select a subcube for allocation. The notion of overlap-syndrome, defined in the text, quantifies the overlap among free subcubes. Our technique has full subcube recognition ability and thus recognizes more subcubes as compared to bit mapped techniques: Buddy, Gray code and its variants. The advantages of our approach over some of the existing ACT's in terms of fragmentation and overall completion time are described in the text and in simulation results.Index Terms¿Hypercube, processor allocation/deallocation, bit-mapped and available cube strategies, subcube recognition, separation factor, overlap syndrome.
DESI methods for stiff initial-value problems
Authors: J. C. Butcher, J. R. Cash, M. T. Diamantakis
Venue: ACM Transactions on Mathematical Software (TOMS) (1996)

Recently, the so-called DESI (diagonally extended singly implicit) Runge-Kutta methods were introduced to overcome some of the limitations of singly implicit methods. Preliminary experiments have shown that these methods are usually more efficient than the standard singly implicit Runge-Kutta (SIRK) methods and, in many cases, are competitive with backward differentiation formulae (BDF). This article presents an algorithm for determining the full coefficient matrix from the stability function, which is already chosen to make the method A-stable. Because of their unconventional nature, DESI methods have to be implemented in a special way. In particular, the effectiveness of these methods depends heavily on how starting values are chosen for the stage iterations. These and other implementation questions are descussed in detail, and design choices we have made form the basis of an experimental coe for the solution of stiff problems by DESI methods. We present here a small subset of the numerical results obtained with our code. Many of these results are quite satisfactory and suggest that DESI methods have a useful role in the solution of this type of problem.
Shaping the focus of the undergraduate curriculum
Authors: Marcin Paprzycki, Janusz Zalewski
Venue: ACM SIGCSE Bulletin (1996)

This paper outlines an approach to reshape the existing undergraduate CS curriculum. Based on software engineering and parallel computing concepts, the details of the new curriculum are presented in terms of educational objectives, core courses, innovations in the teaching method, and early experiences.
Optimal Simulation of Full Binary Trees on Faulty Hypercubes
Authors: Bethany M. Y. Chan, Francis Y. L. Chin, Chung-Keung Poon
Venue: IEEE Transactions on Parallel and Distributed Systems (1995)

We study the problem of running full binary tree based algorithms on a hypercube with faulty nodes. The key to this problem is to devise a method for embedding a full binary tree into the faulty hypercube. Based on a novel embedding strategy, we present two results for embedding an $(n - 1)$-tree (a full binary tree with $2^{n-1} - 1$ nodes) into an $n$-cube (a hypercube with $2^n$ nodes) with unit dilation and load. For the problem where the root of the tree must be mapped to a specified hypercube node (specified root embedding problem), we show that up to $n - 2$ (node or edge) faults can be tolerated. This result is optimal in the following sense: 1) it is time-optimal, 2) $(n - 1)$-tree is the largest full binary tree that can be embedded in an $n$-cube, and 3) $n - 2$ faults is the maximum number of worst-case faults that can be tolerated in the specified root problem. Furthermore, we also show that any algorithm for this problem cannot be totally recursive in nature. For the problem where the root can be mapped to any nonfaulty hypercube node (variable root embedding problem), we show that up to $2n - 3 - \lceil\log n\rceil$ faults can be tolerated. Thus we have improved upon the previous result of $n - 1 - \lceil\log n \rceil.$ In addition, we show that the algorithm for the variable root embedding problem is optimal within a class of algorithms called recursive embedding algorithms as far as the number of tolerable faults is concerned. Finally, we show that when an $O(1/\sqrt{n})$ fraction of nodes in the hypercube are faulty, it is not always possible to have an $O(1)$-load variable root embedding no matter how large the dilation is.Index Terms¿Embedding, hypercubes, full binary trees, dilation, simulation, faulty architecture.
A Family of Antipodal Distance-Regular Graphs Related to the Classical Preparata Codes
Authors: D. De Caen, R. Mathon, G. E. Moorhouse
Venue: Journal of Algebraic Combinatorics: An International Journal (1995)

A new family of distance-regular graphs is constructed. They are antipodal 22t&minus;1-fold covers of the complete graph on 22t vertices. The automorphism groups are determined, and the extended Preparata codes are reconstructed using walks on these graphs.There are connections to other interesting structures: the graphs are equivalent to certain generalized Hadamard matrices&semi; and their underlying 3-class association scheme is formally dual to the scheme of a system of linked symmetric designs obtained from Kerdock sets of skew matrices in characteristic two.
Dagwood: a system for manipulating polynomials given by straight-line programs
Authors: Timothy S. Freeman, Gregory M. Imirzian, Erich Kaltofen, Lakshman Yagati
Venue: ACM Transactions on Mathematical Software (TOMS) (1988)

We discuss the design, implementation, and benchmarking of a system that can manipulate symbolic expressions represented by their straight-line computations. Our system is capable of performing rational arithmetic on, evaluating, differentiating, taking greatest common divisors of, and factoring polynomials in straight-line format. The straight-line results can also be converted to standard, sparse format. We show by example that our system can handle problems for which conventional methods lead to excessive intermediate expression swell.
Formal Specification and Analysis of Software Architectures Using the Chemical Abstract Machine Model
Authors: Paola Inverardi, Alexander L. Wolf
Venue: IEEE Transactions on Software Engineering (1995)

We are exploring an approach to formally specifying and analyzing software architectures that is based on viewing software systems as chemicals whose reactions are controlled by explicitly stated rules. This powerful metaphor was devised in the domain of theoretical computer science by Ban\^ atre and Le Mtayer and then reformulated as the Chemical Abstract Machine, or CHAM, by Berry and Boudol. The CHAM formalism provides a framework for developing operational specifications that does not bias the described system toward any particular computational model. It also encourages the construction and use of modular specifications at different levels of detail. We illustrate the use of the CHAM for architectural description and analysis by applying it to two different architectures for a simple, but familiar, software system, the multiphase compiler.
A probabilistic approach to the problem of automatic selection of data representations
Authors: Tyng-Ruey Chuang, Wen L. Hwang
Venue: Proceedings of the first ACM SIGPLAN international conference on Functional programming (1996)

The designs and implementations of efficient aggregate data structures have been important issues in functional programming. It is not clear how to select a good representation for an aggregate when access patterns to the aggregate are highly variant, or even unpredictable. Previous approaches rely on compile--time analyses or programmer annotations. These methods can be unreliable because they try to predict a program's behavior before it is executed.We propose a probabilistic approach, which is based on Markov processes, for automatic selection of data representations. The selection is modeled as a random process moving in a graph with weighted edges. The proposed approach employs coin tossing at run--time to help choosing a suitable data representation. The transition probability function used by the coin tossing is constructed in a simple and common way from a measured cost function. We show that, under this setting, random selections of data representations can be quite effective. The probabilistic approach is used to implement bag aggregates, and the performance results are compared to those of deterministic selection strategies.