ppxscal/embedding_network huggingface dataset:
ROCK ROLL: A Deductive Object-Oriented Database with Active and Spatial Extensions
Authors: Andrew Dinn, M. Howard Williams, Norman W. Paton
Venue: Proceedings of the Thirteenth International Conference on Data Engineering (1997)

ROCK & ROLL is a deductive object-oriented database system that supports two languages, one imperative and the other deductive, both derived from the same object-oriented data model. As the languages share a common type system, they can be integrated without manifesting impedance mismatches, and thus programmers can conveniently exploit both deductive and imperative features in a single application. The basic ROCK & ROLL system provides comprehensive modelling and programming facilities, but recent work has extended it with both active rules and spatial data types, thereby demonstrating how the core design is amenable to extensions in its behavioural and structural facilities.
The global error of Magnus methods based on the Cayley map for some oscillatory problems
Authors: F. Diele, S. Ragni
Venue: Future Generation Computer Systems (2003)

This paper deals with numerical methods for the discretization of highly oscillatory systems. We approach the problem by writing the solution in terms of the Magnus expansion based on the Cayley map. The global error, obtained when the method is applied to the linear oscillator, is investigated. Moreover, we provide numerical experiments in order to validate our theoretical results.
A tutorial on linear and differential cryptanalysis
Authors: Howard M. Heys
Venue: Cryptologia (2002)

In this paper, we present a detailed tutorial on linear cryptanalysis and differential cryptanalysis, the two most significant attacks applicable to symmetric-key block ciphers. The intent of the paper is to present a lucid explanation of the attacks, detailing the practical application of the attacks to a cipher in a simple, conceptually revealing manner for the novice cryptanalyst. The tutorial is based on the analysis of a simple, yet realistically structured, basic Substitution-Permutation Network cipher. Understanding the attacks as they apply to this structure is useful, as the Rijndael cipher, recently selected for the Advanced Encryption Standard (AES), has been derived from the basic SPN architecture. As well, experimental data from the attacks is presented as confirmation of the applicability of the concepts as outlined.
A Framework for Robust Subspace Learning
Authors: Fernando De La Torre, Michael J. Black
Venue: International Journal of Computer Vision (2003)

Many computer vision, signal processing and statistical problems can be posed as problems of learning low dimensional linear or multi-linear models. These models have been widely used for the representation of shape, appearance, motion, etc., in computer vision applications. Methods for learning linear models can be seen as a special case of subspace fitting. One draw-back of previous learning methods is that they are based on least squares estimation techniques and hence fail to account for &ldquo;outliers&rdquo; which are common in realistic training sets. We review previous approaches for making linear learning methods robust to outliers and present a new method that uses an intra-sample outlier process to account for pixel outliers. We develop the theory of Robust Subspace Learning (RSL) for linear models within a continuous optimization framework based on robust M-estimation. The framework applies to a variety of linear learning problems in computer vision including eigen-analysis and structure from motion. Several synthetic and natural examples are used to develop and illustrate the theory and applications of robust subspace learning in computer vision.
Integrating Knowledge in Groups: How Formal Interventions Enable Flexibility
Authors: Gerardo A. Okhuysen, Kathleen M. Eisenhardt
Venue: Organization Science (2002)

Recent perspectives have focused on the role of the firm in the generation and use of knowledge. These perspectives suggest that, while knowledge is "owned" at the individual level, the integration of this knowledge to a collective level is necessary. This integration of knowledge typically takes place in groups. In our experimental study, we examine how individuals in groups engage in micro-level interactions to effectively integrate knowledge by examining the effects of using three formal interventions: Information Sharing, Questioning Others, and Managing Time. In particular, we observe that simple formal interventions can improve knowledge integration when they lead to "windows of opportunity" for group members to consider ways to improve their work process that go beyond the formal intervention instructions. The most effective groups used these formal interventions to focus their attention into organized clusters of activity, during which they significantly changed their work process and improved their subsequent knowledge integration. In particular, groups in the Questioning Others and Managing Time conditions exhibited greater knowledge integration than groups in the Information Sharing and Control conditions. Groups with high-knowledge integration paced their attention to both adaptive improvements to their process and task execution. Overall, this study identifies simple structures, interruptions, and time pacing as central to the emerging concept of group flexibility by which members enhance their performance on novel and/or ambiguous tasks. We note links to complexity theory and knowledge-based thinking as well.
Bridging Space Over Time: Global Virtual Team Dynamics and Effectiveness
Authors: Martha L. Maznevski, Katherine M. Chudoba
Venue: Organization Science (2000)

Global virtual teams are internationally distributed groups of people with an organizational mandate to make or implement decisions with international components and implications. They are typically assigned tasks that are strategically important and highly complex. They rarely meet in person, conducting almost all of their interaction and decision making using communications technology. Although they play an increasingly important role in multinational organizations, little systematic is known about their dynamics or effectiveness. This study built a grounded theory of global virtual team processes and performance over time. We built a template based on Adaptive Structuration Theory (DeSanctis and Poole 1994) to guide our research, and we conducted a case study, observing three global virtual teams over a period of 21 months. Data were gathered using multiple methods, and qualitative methods were used to analyze them and generate a theory of global virtual team dynamics and effectiveness. First, we propose that effective global virtual team interaction comprises a series of communication incidents, each configured by aspects of the team's structural and process elements. Effective outcomes were associated with a fit among an interaction incident's form, decision process, and complexity. Second, effective global virtual teams sequence these incidents to generate a deep rhythm of regular face-to-face incidents interspersed with less intensive, shorter incidents using various media. These two insights are discussed with respect to other literature and are elaborated upon in several propositions. Implications for research and practice are also outlined.
Using technology to teach technology
Authors: Brenda C. Parker, Thomas J. Cheatham, Justin Milling
Venue: Journal of Computing Sciences in Colleges (2002)

Teaching computer literacy to non-computer science majors presents a challenge to computer science departments. The authors believe that the best way to teach technology concepts and to enhance the learning in computer literacy classes is to engage the students in using technology to learn it. With that in mind, this article reports a measure of success by exposing literacy students to on-line teaching and grading. Personal experiences and student opinion surveys provide evidence that using technology to teach technology to computer literacy students is effective.
Stock Positioning and Performance Estimation in Serial Production-Transportation Systems
Authors: Guillermo Gallego, Paul Zipkin
Venue: Manufacturing Service Operations Management (1999)

This paper considers serial production-transportation systems. In recent years, researchers have developed a fairly simple functional equation that characterizes optimal system behavior, under the assumption of constant leadtimes. We show that the equation covers a variety of stochastic-leadtime systems as well. Still, many basic managerial issues remain obscure: When should stock be held at upstream stages? Which system attributes drive overall performance, and how? To address these questions, we develop and analyze several heuristic methods, inspired by observation of common practice and numerical experiments. One of these heuristics yields a bound on the optimal average cost. We also study a set of numerical examples, to gain insight into the nature of the optimal solution and to evaluate the heuristics.
Structural Analysis of a Queueing System with Multiclasses of Correlated Arrivals and Blocking
Authors: Patricio Del Sol, Pankaj Ghemawat, Susan H. Xu
Venue: Operations Research (1999)

In assemble-to-order production systems, and others of a similar flavor, it is often the case that orders for components of various types are placed simultaneously, but that these components are manufactured or assembled at separate facilities. T he order process introduces correlation among the jobs at separate facilities. The purpose of this paper is to study the effect of this correlation on a variety of system performance measures. Consider a system that consists of s parallel servers, where e ach server has a finite buffer and is dedicated to a separate job type. Multiple classes of customer orders arrive to the system, where each class is composed of one or more unique job types. Upon the arrival of an order, each job in the order is separately routed to its designated buffer; if the buffer is full, that job is blocked and lost; otherwise, it enters the buffer and is served according to the FCFS discipline. Under Markovian assumptions, we systematically examine the impact of arrival correlati ons on system-based performance measures such as the queue length vector and the workload vector and class-based performance measures such as the waiting time vector and the order response time. Among other things, we establish several stochastic orders between performance vectors with different degrees of arrival correlations. We also show that greater arrival correlation can stochastically improve the worst component in a performance vector (e.g., the longest queue, the heaviest workload), reduce the expected sum of the j longest queues, 1 &#8804; j &#8804; s, and, for any given order type, increase its entering probability and reduce its order response time. Our results can also be extended to the compound Poisson arrival process, where each order contains multiple units of several job types.
Enhancing pedagogy via eBay: some assembly (language) required
Authors: Scott B. Hunter
Venue: Journal of Computing Sciences in Colleges (2003)

A number of CPU simulators have been developed, for various purposes, one of which has been to aid in the teaching of assembly language concepts. An alternate and time-honored approach is to use actual, existing systems for this purpose. In this paper, it is argued that these form two ends of a spectrum of approaches, and that there is a point somewhere in the middle that preserves many of the benefits of both ends: through the use of the SPIM simulator for the MIPS CPU, and a modest purchase on eBay, our students have not only had the flexibility and educational benefits that a simulator provides, but have also been able to apply that knowledge to investigating and manipulating a real computer that uses those very same instructions. Some of the activities that were developed for this purpose are presented, as well as some ideas for further use of this equipment.
Applying fixed point homotopy to nonlinear DAEs deriving from switching circuits
Authors: E. Chiarantoni, G. Fornarelli, S. Vergura, T. Politi
Venue: Future Generation Computer Systems (2003)

The time-domain analysis of switching circuits is a time consuming process as the change of switch state produces sharp discontinuities in switch variables. In this paper, a method for fast time-domain analysis of switching circuits is described. The proposed method is based on piecewise temporal transient analysis windows joined by DC analysis at the switching instants. The DC analysis is carried out by means of fixed point homotopy to join operating points between consecutive time windows. The proposed method guarantees accurate results reducing the number of iterations needed to simulate the circuit.
Explicit bounds for the positive root of classes of polynomials with applications
Authors: Jürgen Herzberger
Venue: Journal of Computational and Applied Mathematics (2003)

We consider a certain type of polynomial equations for which there exists--according to Descartes' rule of signs--only one simple positive root. These equations are occurring in Numerical Analysis when calculating or estimating the R-order or Q-order of convergence of certain iterative processes with an error-recursion of special form. On the other hand, these polynomial equations are very common as defining equations for the effective rate of return for certain cashflows like bonds or annuities in finance. The effective rate of interest i* for those cashflows is i* = q* - 1, where q* is the unique positive root of such polynomial. We construct bounds for i* for a special problem concerning an ordinary simple annuity which is obtained by changing the conditions of such an annuity with given data applying the German rule (Preisangabeverordnung or short PAngV). Moreover, we consider a number of results for such polynomial roots in Numerical Analysis showing that by a simple variable transformation we can derive several formulas out of earlier results by applying this transformation. The same is possible in finance in order to generalize results to more complicated cashflows.
Symbolic pointer analysis
Authors: Jianwen Zhu
Venue: Proceedings of the 2002 IEEE/ACM international conference on Computer-aided design (2002)

One of the bottlenecks in the recent movement of hardware synthesis from behavioral C programs is the difficulty in reasoning about runtime pointer values at compile time. The pointer analysis problem has been investigated in the compiler community for two decades, which has yielded efficient, polynomial time algorithms for context-insensitive analysis. However, at the accuracy level for which hardware synthesis is desired, namely context and flow sensitive analysis, the time and space complexity of the best algorithms reported grow exponentially with program size. In this paper, we present our first step towards a new analysis technology which potentially leads to almost-linear time complexity and sub-linear space complexity algorithm even for the most accurate analysis. The key idea that contributes to this efficiency is to implicitly encode the pointer-to relation in the Boolean domain, thereby capturing the procedure transfer function completely, compactly and canonically. This represents a wide departure from the traditional techniques, all of which explicitly capture pointer-to relation using variations of point-to graph, which have to be re-evaluated for different calling contexts. Experiments for our first flow-insensitive algorithm on common benchmarks show promising result.
Computer aided conceptual design: a review
Authors: J. C. Miles
Venue: Civil and structural engineering computing: 2001 (2001)

Although computer based tools have been available to designers for many years, these have largely been for analysis and drafting. For the past two decades, research has been undertaken into the identification and development of software technologies to support conceptual design. This paper reviews the main developments. The volume of the research work is such that it is necessary to limit the scope of the paper and so it focuses on the AEC industry and in particular the design of bridges and buildings. However where other techniques of generic interest have been developed outside this domain these are described. The paper looks at the lessons learned to date; reviews the successes and failures and then briefly looks forward to what current trends suggest will be potentially useful areas to investigate in the future.
A hybrid multigrid method for the unsteady incompressible Navier-Stokes equations
Authors: Zhang Shesheng
Venue: Applied Mathematics and Computation (2003)

An approach is presented for the high Reynolds incompressible flow, based on multigrid method and sequential regular method. In this paper, the velocity-pressure increment and sequential regular equations are derived from the Navier-Stokes equation. The pressure increment optimum sweep algorithm is discussed. The numerical results of the close square flow show that our algorithm improves the convergence rate for high Reynolds unsteady flow.
Proximity templates for modeling of skin and proximity effects on packages and high frequency interconnect
Authors: Luca Daniel, Alberto Sangiovanni-Vincentelli, Jacob White
Venue: Proceedings of the 2002 IEEE/ACM international conference on Computer-aided design (2002)

Modeling the exponentially varying current distributions in conductor interiors associated with high frequency interconnect behavior causes a rapid increase in the computation time and memory required even by recently developed fast electromagnetic analysis programs. In this paper we describe a procedure to generate numerically a set of basis functions which efficiently represent conductor current variation, and thus improving solver efficiency. The method is based on solving a sequence of template problems, and is easily generalized to arbitrary conductor cross-sections. Results are presented to demonstrate that the numerically computed basis functions are seven to twenty times more efficient than the commonly used piece-wise constant basis functions.
A Branch and Bound Algorithm for the Stability Number of a Sparse Graph
Authors: E. C. Sewell
Venue: INFORMS Journal on Computing (1998)

We present a branch and bound algorithm for finding a maximum stable set in a graph. The algorithm uses properties of the stable set polytope to construct strong upper bounds. Specifically, it uses cliques, odd cycles, and a maximum matching on the remaining nodes. The cliques are generated via standard coloring heuristics, and the odd cycles are generated from blossoms found by a matching algorithm. We report computational experience on two classes of randomly generated graphs and on the DIMACS Challenge Benchmark graphs. These experiments indicate that the algorithm is quite effective, particularly for sparse graphs.
Digital System Clocking: High-Performance and Low-Power Aspects
Authors: Vojin G. Oklobdzija, Vladimir M. Stojanovic, Dejan M. Markovic, Nikola M. Nedovic
Venue:  (2003)

:Provides the only up-to-date source on the most recent advances in this often complex and fascinating topic. The only book to be entirely devoted to clocking Clocking has become one of the most important topics in the field of digital system design. A "must have" book for advanced circuit engineers
Internal OR Consulting: Effective Practice in a Changing Environment
Authors: Robert Fildes, John Ranyard
Venue: Interfaces (2000)

Around 1970 some 96 percent of the largest Fortune-500 companies had established OR groups. The recessions of the '70s and '80s led many to close their groups. In 1993, the UK OR Society, disturbed by further closures, funded a study to identify factors that influenced the success and survival of internal OR groups. The study team found three categories of factors: changes in the external environment, in the organization, and in the OR group's management. This research shows that to be effective, an OR group needs good consulting skills, expert project management, active marketing of its services, and responsiveness to changes in its clients' requirements and in the surrounding organizational culture.
Growth in adversity: non-economic factors in telecommunications development in China
Authors: Harina Suk-Ching Tang, Paul S. N. Lee
Venue: Telematics and Informatics (2003)

It is generally conceived that economic growth contributes to telecommunications development. This study examines the role of the state and its military strategic considerations in the presumed link of economic growth and telecommunications development. A study on an interior Chinese province, namely, Shaanxi, shows that telecommunications development in China depends not merely on economic factors, but also on non-economic factors such as political, historical and national security considerations. The interplay of the state and economic growth determines whether a particular region is having maximum, medium or minimum growth in the telecommunications sector. Based on the interplay of the state factor and economic growth, a model for telecommunications planning in developing countries is proposed.
Effect of Relapse to High-Risk Behavior on the Costs and Benefits of a Program to Screen Women for Human Immunodeficiency Virus
Authors: Douglas K. Owens, Margaret L. Brandeau, Carol H. Sox
Venue: Interfaces (1998)

We carried out an analysis to determine the effect of women's relapse to high-risk sexual and needle-sharing behavior on the costs and benefits of a voluntary program to screen women of childbearing age for HIV, the virus that causes AIDS. The analysis is based on a dynamic model of the HIV epidemic, combined with an economic model that assesses costs and benefits of such a program. We find that, for women with high prescreening levels of high-risk behavior, even small and short-lived reductions in sexual or needle-sharing high-risk behaviors in response to counseling and testing can produce benefits that outweigh costs. The effect of relapse to high-risk behaviors on screening program costs and benefits can be substantial, and this effect is most notable in screening programs that reach women of all risk groups. Behavioral interventions that produce sustained reductions in risk behavior could be cost saving even if the interventions were expensive.
Local Convergence of the Proximal Point Algorithm and Multiplier Methods Without Monotonicity
Authors: Teemu Pennanen
Venue: Mathematics of Operations Research (2002)

This paper studies the convergence of the classical proximal point algorithm without assuming monotonicity of the underlying mapping. Practical conditions are given that guarantee the local convergence of the iterates to a solution ofT( x) ? 0, whereT is an arbitrary set-valued mapping from a Hilbert space to itself. In particular, when the problem is "nonsingular" in the sense thatT-1 has a Lipschitz localization around one of the solutions, local linear convergence is obtained. This kind of regularity property of variational inclusions has been extensively studied in the literature under the name ofstrong regularity, and it can be viewed as a natural generalization of classical constraint qualifications in nonlinear programming to more general problem classes. Combining the new convergence results with an abstract duality framework for variational inclusions, the author proves the local convergence of multiplier methods for a very general class of problems. This gives as special cases new convergence results for multiplier methods for nonmonotone variational inequalities and nonconvex nonlinear programming.