ppxscal/embedding_network huggingface dataset:
Effects of peer interaction facilitated by computer-mediated conferencing on learning outcomes
Authors: Charlotte N. Gunawardena
Venue:  (2003)

Social interaction has always been a defining characteristic of education, training, and more generally of learning. Interaction with others offers the potential for collaboration, negotiation of meaning, mutually shared knowledge, and the joint construction of solutions that otherwise could not be produced alone. Computer-mediated conferencing (CMC) gives designers and instructors of distance education programs the potential to design courses incorporating interaction among class members. While many studies report the advantages and disadvantages of incorporating CMC into the design of distance education, few studies report whether achievement of effective learning outcomes were facilitated by peer interaction. Consequently, many researchers suggest our pervasive adoption of CMC has far outpaced our understanding of what makes peer interaction good and when peer interaction is good. This study addressed that concern and tested a model of five variables&mdash;learner characteristics (measured by self-construal), teaching style, task design, course requirements, and prior CMC experience&mdash;and their impact upon peer interaction and learning outcomes. The model was derived from an extensive review of the literature and tested with structural equation modeling. Adjustments were made to the original five-construct model based on theory and developments in the research process. A simplified three-construct model and two-construct model revealed the significant effect of peer interaction on learning outcomes. The two-construct model of peer interaction in an online course was a better fit to the data. The two-construct model showed a path coefficient of .66 from peer interaction to learning outcomes. This finding indicated that for every one standard deviation increase in peer interaction, there was a .66 standard deviation change in learning outcomes&mdash;a large, strong effect. The variables, teaching style and prior CMC experience, plus peer interaction accounted for 65% of the variance in learning outcomes. When peer interaction was temporarily dropped from the two-construct model, teaching style and prior CMC experience accounted for only 29% of the variance in learning outcomes. While the literature has pointed to and suggested this relationship, this study has been able to show (a) the relationship between peer interaction and learning outcomes and (b) its significance.
Tabsol decision table preprocessor
Authors: Robert F. Sterbenz
Venue: ACM SIGPLAN Notices (1971)

This paper describes the Tabsol Decision Table Preprocessor, a program product of the B.F. Goodrich Company. The Tabsol (Tabular systems oriented language) Preprocessor, itself written in ANSI Cobol, is designed to translate horizontalrule, extended-entry decision tables into equivalent Cobol statements. Design objectives, language format and implementation results of the Tabsol Preprocessor are summarized in this paper. This preprocessor has been in full production use by the Information Systems Department of B.F. Goodrich Chemical Company since January 1971.
On a Conjecture by Eriksson Concerning Overlap in Strings
Authors: Isa Cakir, Ourania Chryssaphinou, Marianne Månsson
Venue: Combinatorics, Probability and Computing (1999)

Consider a finite alphabet &Omega; and strings consisting of elements from &Omega;. For a given string w, let cor(w) denote the autocorrelation, which can be seen as a measure of the amount of overlap in w. Furthermore, let aw(n) be the number of strings of length n that do not contain w as a substring. Eriksson [4] stated the following conjecture: if cor(w)>cor(w&prime;), then aw(n)>aw&prime;(n) from the first n where equality no longer holds. We prove that this is true if &#x2223;&Omega;&#x2223;&ge;3, by giving a lower bound for aw(n)&minus;aw&prime;(n).
SmartTutor: an intelligent tutoring system in web-based adult education
Authors: B. Cheung, L. Hui, J. Zhang, S. M. Yiu
Venue: Journal of Systems and Software (2003)

This paper describes the design of SmartTutor, an intelligent tutoring system implemented for distance learning in Hong Kong. Many projects and researches on online distance learning have been carried out in these few years. Most of them emphasized on the application of multimedia elements, but did not pay much attention on two crucial elements: personalization and intelligent tutoring, which are important for life-long/adult education. School of Professional and Continuing Education, The University of Hong Kong (HKU SPACE) has developed SmartTutor to address these two issues. This project can be treated as a case study of combining Internet technology, education research, and artificial intelligence. The SmartTutor has been integrated into the SPACE Online Universal Learning platform (an online learning platform), which provides support to courses offered by HKU SPACE. The effectiveness of SmartTutor has been evaluated and the results are very positive.
Solving Large Scale Semidefinite Programs via an Iterative Solver on the Augmented Systems
Authors: Kim-Chuan Toh
Venue: SIAM Journal on Optimization (2003)

The search directions in an interior-point method for large scale semidefinite programming (SDP) can be computed by applying a Krylov iterative method to either the Schur complement equation (SCE) or the augmented equation. Both methods suffer from slow convergence as interior-point iterates approach optimality. Numerical experiments have shown that a diagonally preconditioned conjugate residual method on the SCE typically takes a huge number of steps to converge. However, it is difficult to incorporate cheap and effective preconditioners into the SCE. This paper proposes to apply the preconditioned symmetric quasi-minimal residual (PSQMR) method to a reduced augmented equation that is derived from the augmented equation by utilizing the eigenvalue structure of the interior-point iterates. Numerical experiments on SDP problems arising from maximum clique and selected SDPLIB (SDP Library) problems show that moderately accurate solutions can be obtained with a modest number of PSQMR steps using the proposed preconditioned reduced augmented equation. An SDP problem with 127600 constraints is solved in about 6.5 hours to an accuracy of 10-6 in relative duality gap.
The combination limit in multimedia retrieval
Authors: Rong Yan, Alexander G. Hauptmann
Venue: Proceedings of the eleventh ACM international conference on Multimedia (2003)

Combining search results from multimedia sources is crucial for dealing with heterogeneous multimedia data, particularly in multimedia retrieval where a final ranked list of items of interest is returned sorted by confidence or relevance. However, relatively little attention has been given to combination functions, especially their upper bound performance limits. This paper presents a theoretical framework for studying upper bounds for two types of combination functions. A general upper bound and two approximations are proposed for monotonic combination functions. We also studied the upper bounds for linear combination functions using a global optimization technique. Our experimental results show that the choice of combination functions has a considerable influence to retrieval performance.
Algorithmic Macromodelling Methods for Mixed-Signal Systems
Authors: Jaijeet Roychowdhury
Venue: Proceedings of the 17th International Conference on VLSI Design (2004)

Electronic systems today, especially those for communications and sensing, are typically composed of a complex mix ofdigital and mixed-signal circuit blocks. Verifying such systemsprior to fabrication is challenging due to their size and complexity. Automated model generation is becoming an increasingly important component of methodologies for effective system verification. In this paper, we review algorithmically-basedmodel generation methods for linear and nonlinear systems. Wecomment on the development of such macromodelling methodsover the last decade, clarify their domains of application andevaluate their strengths and current limitations.
Power Supply Current Test Approach for Resistive Fault Screening in Embedded Analog Circuits
Authors: Marco S. Dragic, Martin Margala
Venue: Proceedings of the 18th IEEE International Symposium on Defect and Fault Tolerance in VLSI Systems (2003)

A feasibility of non-specification based method for testing of analog integrated circuits in 0.13µm CMOS process has been explored. The method is an extension of digital IDD test to analog circuits. We investigated detection rate of resistive open and short faults within a MOSFET device in several analog circuits implemented in 0.13µm CMOS technology. Input test signals are optimized for maximum detectability of introduced faults. Stimulus required for defect screening are DC signals which can be easily produced on-chip. It is shown in this paper that with respect to the used fault models the detection success rate for introduced faults is 100% for resistive shorts and 67% for resistive opens. This simple method is suitable for production testing, as a preliminary and complementary test of embedded analog circuits for early defect screening in highly integrated environment.
A Failure to Learn from the Past
Authors: Eugene H. Spafford
Venue: Proceedings of the 19th Annual Computer Security Applications Conference (2003)

On the evening of 2 November 1988, someone "infected"the Internet with a worm program. That program exploitedflaws in utility programs in systems based on BSD-derivedversions of UNIX. The flaws allowed the program to breakinto those machines and copy itself, thus infecting those systems.This program eventually spread to thousands of machines,and disrupted normal activities and Internet connectivityfor many days. It was the first major network-wideattack on computer systems, and thus was a matter of considerableinterest.This paper provides a brief chronology of both the spreadand eradication of the program, a presentation about howthe program worked, and details of the aftermath. That isfollowed by discussion of some observations of what hashappened in the years since that incident. The discussionsupports the title of this paper - that the community hasfailed to learn from the past.
Solving the 0/1 knapsack problem using an adaptive genetic algorithm
Authors: Zoheir Ezziane
Venue: Artificial Intelligence for Engineering Design, Analysis and Manufacturing (2002)

Probabilistic and stochastic algorithms have been used to solve many hard optimization problems since they can provide solutions to problems where often standard algorithms have failed. These algorithms basically search through a space of potential solutions using randomness as a major factor to make decisions. In this research, the knapsack problem (optimization problem) is solved using a genetic algorithm approach. Subsequently, comparisons are made with a greedy method and a heuristic algorithm. The knapsack problem is recognized to be NP-hard. Genetic algorithms are among search procedures based on natural selection and natural genetics. They randomly create an initial population of individuals. Then, they use genetic operators to yield new offspring. In this research, a genetic algorithm is used to solve the 0/1 knapsack problem. Special consideration is given to the penalty function where constant and self-adaptive penalty functions are adopted.
Sketch based interfaces: early processing for sketch understanding
Authors: Tevfik Metin Sezgin, Thomas Stahovich, Randall Davis
Venue: Proceedings of the 2001 workshop on Perceptive user interfaces (2001)

Freehand sketching is a natural and crucial part of everyday human interaction, yet is almost totally unsupported by current user interfaces. We are working to combine the exibility and ease of use of paper and pencil with the processing power of a computer, to produce a user interface for design that feels as natural as paper, yet is considerably smarter. One of the most basic steps in accomplishing this is converting the original digitized pen strokes in a sketch into the intended geometric objects. In this paper we describe an implemented system that combines multiple sources of knowledge to provide robust early processing for freehand sketching.
Sampling-efficient mesh parametrization
Authors: Steven J. Gortler
Venue:  (2003)

Texture-mapping is a traditional graphics technique that has several applications in computer graphics rendering. It uses surface signals to achieve a variety of rendering effects, including color mapping, bump mapping (where surface normals are the signal), displacement mapping (geometry), and self-shadowing. While these rendering effects can also be computed in vertex shaders, texture-mapping is advantageous because storing and processing texture images is generally more efficient than refining the geometry to represent the detailed signal at the vertices of a dense mesh. To allow texture-mapping, a surface must be parametrized onto a texture domain by assigning texture coordinates to its vertices. This thesis presents new metrics and algorithms to parametrize a 3D surface onto the 2D domain for the purpose of texture-mapping. The main contributions of this thesis are two &ldquo;stretch-based&rdquo; parametrization algorithms. As opposed to previous methods, our new geometric-stretch metric directly minimizes geometry undersampling in the texture domain. Our novel signal-stretch metric constructs a parametrization that is specialized to store a given surface signal while attempting to minimize a measure of signal approximation error. This latter metric allocates more texture samples to regions of the surface where there is higher signal variation. These metrics allow for more efficient use of the texture-map, yielding significantly better results than previous approaches for storing signals over surfaces. Two mesh parametrization algorithms that optimize the abovementioned metrics are presented. The first algorithm is based on iterative local optimization of the texture coordinates, while the second algorithm employs hierarchical techniques to accelerate the process and improve results. These algorithms can also be used to optimize other parametrization metrics. In order to handle complex meshes that cannot be parametrized onto the plane without incurring severe distortion, we present methods to partition a complex mesh into multiple charts that are suitable for parametrization. We also present methods to efficiently pack the parametrized 2D charts onto a texture atlas. All of the above methods allow us to create efficient parametrizations of complex meshes. We also describe additional techniques to parametrize progressive meshes so that the same texture-map can be used for all levels of detail. Finally, we show some recent results of applying our parametrization methods to resample the model's geometry itself.
Testing the Suitability of Markov Chains as Web Usage Models
Authors: Zhao Li, Jeff Tian
Venue: Proceedings of the 27th Annual International Conference on Computer Software and Applications (2003)

Markov chains have been used to model web usages andserved as the basis for statistical testing, performance evaluation,and reliability analysis. However, most of such applicationsof Markov chains were carried out without answeringthe question: "Can web usage be accurately modeledby Markov chains?" In this paper, we propose a set oftests, which are easy to perform based on information aboutweb link usage frequencies gathered from web server logs,to answer this question. We applied this approach to ouruniversity's web site, and our results indicate that Markovchains can provide fairly accurate models of web usages.
Hierarchical Adaptive Dynamic Power Management
Authors: Zhiyuan Ren, Bruce H. Krogh, Radu Marculescu
Venue: Proceedings of the conference on Design, automation and test in Europe - Volume 1 (2004)

The main contribution of this paper is a novel hierarchical scheme for adaptive dynamic power management (DPM) under nonstationary service requests. We model the nonstationary arrival process of service requests as a Markov-modulated stochastic process in which the stochastic process for each modulation state models a particular stationary mode of the arrival process. The bottom layer of our hierarchical architecture is a set of stationary optimal DPM policies, precalculated off-line for selected modes from policy optimization in Markov decision processes. The supervisory power manager at the top layer adaptively and optimally switches among these stationary policies on-line to accommodate the actual mode-switching arrival dynamics. Simulation results show that our approach, under highly nonstationary requests, canlead to significant power savings compared to previously proposed heuristic approaches.
AFRED: An Adaptive Fuzzy-based Control Algorithm for Active Queue Management
Authors: Chonggang Wang, Bo Li, Kazem Sohraby, Yong Peng
Venue: Proceedings of the 28th Annual IEEE International Conference on Local Computer Networks (2003)

This paper studies the active queue management(AQM) in high-speed routers. One of the original andpopularly implemented AQM algorithms is random earlydetection (RED). But it is hard to configure theparameters involved in RED. Although there are somenew TCP-modeling based approaches to overcome this,they really show some instability under such dynamicalenvironments with diverse connections (adaptive or non-adaptive,short or long), link rate, RTT, and buffer size.The major reason is that these approaches are primarilybased on TCP model, which has some mismatches underdynamical environment. Since Fuzzy-logic control doesnot need precise control model, it may be suitable forsuch environment. This paper designs an adaptive fuzzy-basedcontrol algorithm (AFRED), which computes thepacket drop (or marking) probability according to pre-configuredfuzzy logic using the instant queue length asinput variable. The important feature of AFRED is that italso designs an adaptive mechanism to dynamically re-adjustthe fuzzy rule so as to make AFRED itselfextensively stable for many dynamic environments.Simulation results show that AFRED can effectively andstably control the queue length to the expected value orso. Compared with RED and PI algorithm, AFREDobtains higher goodput and stable queue length thanRED and PI, even if introducing UDP flows.
An event structure based semantics for high-level message sequence charts
Authors: Loïc Hélouët, Claude Jard, Benoît Caillaud
Venue: Mathematical Structures in Computer Science (2002)

This paper details a partial order semantics for families of scenarios represented by High-Level Message Sequence Charts (HMSCs): graph grammars generating event structures are used to represent HMSCs. A decision procedure for HMSC equivalence is then described. This can be considered as a first step towards the formal manipulation of scenarios.
An Industrial Case Study of Immediate Benefits of Requirements Engineering Process Improvement at the Australian Center for Unisys Software
Authors: Daniela Damian, Didar Zowghi, Lakshminarayanan Vaidyanathasamy, Yogendra Pal
Venue: Empirical Software Engineering (2004)

This paper describes an industrial experience in process improvement at one of the Unisys development labs in Australia. Following a capability maturity model (CMM) mini-assessment, the organization is undertaking significant changes in the requirements management process, which include the introduction of group session approaches to requirements analysis and a structured method for writing requirements. An empirical evaluation which investigated other aspects of the process improvement than the CMM model indicates tangible benefits as well as perceived long-term benefits during design and testing. Findings confirm that a more thorough requirements analysis results in more clearly defined, better understood and specified requirements, and an enhanced ability to address the market needs and product strategy requirements. The catalyst behind these improvements included project management leadership, managing the human dimension, collaboration among stakeholders and senior management support.
A partial differential equation approach to multidimensional extrapolation
Authors: Tariq D. Aslam
Venue: Journal of Computational Physics (2004)

In this short note, a general methodology for multidimensional extrapolation is presented. The approach assumes a level set function exists which separates the region of known values from the region to be extrapolated. It is shown that arbitrary orders of polynomial extrapolation can be formulated by simply solving a series of linear partial differential equations (PDEs). Examples of constant, linear and quadratic extrapolation are given.
Number-theoretic constructions of efficient pseudo-random functions
Authors: Moni Naor, Omer Reingold
Venue: Journal of the ACM (JACM) (2004)

We describe efficient constructions for various cryptographic primitives in private-key as well as public-key cryptography. Our main results are two new constructions of pseudo-random functions. We prove the pseudo-randomness of one construction under the assumption that factoring (Blum integers) is hard while the other construction is pseudo-random if the decisional version of the Diffie--Hellman assumption holds. Computing the value of our functions at any given point involves two subset products. This is much more efficient than previous proposals. Furthermore, these functions have the advantage of being in TC0 (the class of functions computable by constant depth circuits consisting of a polynomial number of threshold gates). This fact has several interesting applications. The simple algebraic structure of the functions implies additional features such as a zero-knowledge proof for statements of the form "y &equals; fs(x)" and "y &neq; fs(x)" given a commitment to a key s of a pseudo-random function fs.
Inequalities involving complex rational functions
Authors: Xin Li
Venue:  (2003)

In this work, it is our intention to give a systematic overview of the current status of the study of several classes of inequalities involving complex algebraic polynomials and rational functions. Complete proofs of these known results are presented in detail and in a unified way. In selecting the proofs, the most important criterion is whether the underlying techniques can be extended and used in more general settings. The final chapters contain new results involving the integral means of rational functions and their derivatives for the special case of a rational function with a single pole outside the unit disk and results that follow directly from this particular case. Numerical and symbolic experiments are also presented in order to gain insight on the general case. Indications are given of methods that may be used to overcome the difficulty associated with extending the techniques of proof used in polynomial inequalities to rational functions.
Adding and Reversing Arcs in Semicomplete Digraphs
Authors: Jørgen Bang-Jensen, Tibor Jordán
Venue: Combinatorics, Probability and Computing (1998)

Let T be a semicomplete digraph on n vertices. Let ak(T) denote the minimum number of arcs whose addition to T results in a k-connected semicomplete digraph and let rk(T) denote the minimum number of arcs whose reversal in T results in a k-connected semicomplete digraph. We prove that if n&ge;3k&minus;1, then ak(T)=rk(T). We also show that this bound on n is best possible.