ppxscal/embedding_network huggingface dataset:
Auditory and visual feedback during eye typing
Authors: Päivi Majaranta, I. Scott MacKenzie, Anne Aula, Kari-Jouko Räihä
Venue: CHI '03 extended abstracts on Human factors in computing systems (2003)

We describe a study on how auditory and visual feedback affects eye typing. Results show that the feedback method influences both text entry speed and error rate. In addition, a proper feedback mode facilitates eye typing by reducing the user's need to switch her gaze between the on-screen keyboard and the typed text field.
Constructive recognition of classical groups in their natural representation
Authors: Peter A. Brooksbank
Venue: Journal of Symbolic Computation (2003)

Let S ⊂ GL(V) be a given set of generators for a group G, where V is a finite-dimensional vector space over a finite field F. We present an algorithm which recognises, constructively, when G is Sp(V), SU(V) Ωε(V) . Our algorithm handles all of those classical groups uniformly and runs in time which is polynomial in the input length, assuming a discrete logarithm oracle for F.
Pivot Vector Space Approach for Audio-Video Mixing
Authors: Philippe Mulhem, Mohan S. Kankanhalli, Ji Yi, Hadi Hassan
Venue: IEEE MultiMedia (2003)

An audio-mixing artist usually adds the musicalaccompaniment to video. Employing such artists isexpensive and not feasible for a home videopresentation. Our automatic audioývideo mixingtechnique is suited for home videos. It uses a pivotvector space mapping method that matches video shotswith music segments based on aestheticcinematographic heuristics.
Computable error bounds for coefficients perturbation methods
Authors: M. K. El-Daou
Venue: Computing (2002)

The coefficients perturbation method (CPM) is a numerical technique for solving ordinary differential equations (ODE) associated with initial or boundary conditions. The basic principle of CPM is to find the exact solution of an approximation problem obtained from the original one by perturbing the coefficients of the ODE, as well as the conditions associated to it. In this paper we shall develop formulae for calculating tight error bounds for CPM when this technique is applied to second order linear ODEs. Unlike results reported in the literature, ours do not require any a priori information concerning the exact error function or its derivative. The results of this paper apply in particular to the Tau Method and to any approximation procedure equivalent to it. The convergence of the derived bounds is also discussed, and illustrated numerically.
A 29.5 Tflops simulation of planetesimals in Uranus-Neptune region on GRAPE-6
Authors: Junichiro Makino, Eiichiro Kokubo, Toshiyuki Fukushige, Hiroshi Daisaka
Venue: Proceedings of the 2002 ACM/IEEE conference on Supercomputing (2002)

As an entry for the 2002 Gordon Bell performance prize, we report the performance achieved on the GRAPE-6 system for a simulation of the early evolution of the protoplanet-planetesimal system of the Uranus-Neptune region. GRAPE-6 is a special-purpose computer for astrophysical N-body calculations. The present configuration has 2048 custom pipeline chips, each containing six pipeline processors for the calculation of gravitational interactions between particles. Its theoretical peak performance is 63.4 Tflops. The actual performance obtained was 29.5 Tflops, for a simulation of the early evolution of outer Solar system with 1.8 million planetesimals and two massive protoplanets.
A sample database used in a palm OS programming course
Authors: W. Douglas Maurer
Venue: Journal of Computing Sciences in Colleges (2003)

We present a database whose data is taken from the Nutrition Facts labels required on food and drink containers. We also present a program which acts on such a database, which we call NuFax. This program illustrates a large number of Palm OS concepts, such as scrolling lists and tables, scroll bars and scroll buttons, application preferences, categories, beaming, and the global find. The C code for this program is available electronically from the author.
Designing for changing work and business practices
Authors: Yvonne Dittrich, Olle Lindeberg
Venue: Adaptive evolutionary information systems (2003)

Changes in the use context of computer programs require flexibility and adaptability of the software itself. But, how do you design for change in rapidly changing environments? Based on a case study, the chapter argues that it is not enough to only relate to the use context. Taking also technical and developmental contexts and how they relate to the use context into consideration, allows for light-weight solutions for adaptable special purpose software. The conceptualisation of design as "artful integration" of different contexts provides a starting point for a systematic identification of relevant contexts and evaluation of design alternatives in relation to these contexts.
The finite power property in free groups
Authors: Flavio d'Alessandro, Jacques Sakarovitch
Venue: Theoretical Computer Science (2003)

We show that the finite power property is decidable for rational sets in the free group. The complexity of the construction involved in the decision procedure may be lowered to O(n3)-- where n is the cardinality of the state set of the automaton that defines the rational set.
Testing Juntas
Authors: Eldar Fischer, Guy Kindler, Dana Ron, Shmuel Safra, Alex Samorodnitsky
Venue: Proceedings of the 43rd Symposium on Foundations of Computer Science (2002)

We show that a Boolean function over n Boolean variables can be tested for the property of depending on only k of them, using a number of queries that depends only on k and the approximation parameter \varepsilon. We present two tests, both non-adaptive, that require a number of queries that is polynomial k and linear in \varepsilon ^{- 1}. The first test is stronger in that it has a 1-sided error, while the second test has a more compact analysis. We also present an adaptive version and a 2-sided error version of the first test, that have a somewhat better query complexity than the other algorithms.We then provide a lower bound of \bar \Omega (\sqrt k) on the number of queries required for the non-adaptive testing of the above property; a lower bound of \Omega (\log (k + 1)) for adaptive algorithms naturally follows from this. In providing this we also prove a result about random walks on the group {\rm Z}_2^9 that may be interesting in its own right. We show that for some t(q) = \bar 0(q^2) the distributions of the random walk at times t and t + 2 are close to each other, independently of the step distribution of the walk.We also discuss related questions. In particular, when given in advance a known k-junta function h, we show how to test a function f for the property of being identical to h up to a permutation of the variables, in a number of queries that is polynomial in k and \varepsilon.
On bandwidth allocation for data dissemination in cellular mobile networks
Authors: Jianliang Xu, Dik L. Lee, Bo Li
Venue: Wireless Networks (2003)

Wireless bandwidth is a scarce resource in a cellular mobile network. As such, it is important to effectively allocate bandwidth to each cell such that the overall system performance is optimized. Channel allocation strategies have been extensively studied for voice communications in cellular networks. However, for data dissemination applications, studies on bandwidth allocation have thus far been limited to a single-cell environment. This paper investigates the problem of bandwidth allocation for data dissemination in a multicell environment, which, to the best of our knowledge, has not been investigated before. The performance objective is to minimize the overall expected access latency given the workload for each cell in a data dissemination system. Two heuristic techniques, called compact allocation and cluster-step allocation, are proposed to effectively allocate bandwidth for a cellular network. Simulation experiments are conducted to evaluate the performance of the proposed bandwidth allocation schemes. Experimental results show that the proposed schemes substantially outperform the uniform allocation and proportional allocation schemes.
A mixed-type finite element approximation for radiation problems using fictitious domain method
Authors: H. M. Nasir, T. Kako, D. Koyama
Venue: Journal of Computational and Applied Mathematics (2003)

In the finite element approximation of the exterior Helmholtz problem, we propose an approximation method to implement the DtN mapping formulated as a pseudo-differential operator on a computational artificial boundary. The method is then combined with the fictitious domain method. Our method directly gives an approximation matrix for the sesqui-linear form for the DtN mapping. The eigenvalues of the approximation matrix are simplified to a closed form and can be computed efficiently by using a continued fraction formula. Solution outside the computational domain and the far-field solution can also be computed efficiently by expressing them as operations of pseudo-differential operators. An inner artificial DtN boundary condition is also implemented by our method. We prove the convergence of the solution of our method and compare the performance with the standard finite element approximation based on the Fourier series expansion of the DtN operator. The efficiency of our method is demonstrated through numerical examples.
Understanding functional programming
Authors: Richard Wyatt
Venue: Journal of Computing Sciences in Colleges (2003)

In my programming languages course, I have found that an effective and convincing introduction to functional programming is harder to deliver than might be thought. Careful communications with students has revealed that they are largely unconvinced that functional programming is importantly different from imperative programming. After much time, I have diagnosed the problem to be the lack of an alternative to the Von Neumann model. I argue that including the ?-calculus and its resulting model, which is absent from the standard programming language texts, is essential for students to understand functional programming.
Models and Algorithms for Container Allocation Problems on Trains in a Rapid Transshipment Shunting Yard
Authors: Nathalie Bostel, Pierre Dejax
Venue: Transportation Science (1998)

Multimodal transport of containers can be an alternative to the road transportation but it requires to be competitive in terms of quality of service and price. In railÂ rail container terminals, new techniques are developed to facilitate rapid transfers of the containers between trains. In this article, we address the problem of the optimization of the operations management of rapid railÂ rail transshipment shunting yards. We are interested specifically in the optimization of containers allocation on tra ins (for the initial loading and their reloading after transshipment). We have developed a class of models with different levels of complexity and realism and we have proposed optimal and heuristic methods to solve them. The experimental results on realistic datasets are very promising in terms of the minimization of the container moves in a terminal as well as the use and sizing of the handling equipments.
Chu spaces as a semantic bridge between linear logic and mathematics
Authors: Vaughan Pratt
Venue: Theoretical Computer Science (2003)

The motivating role of linear logic is as a "logic behind logic". We propose a sibling role for it as a logic of transformational mathematics via the self-dual category of Chu spaces, a generalization of topological spaces. These create a bridge between linear logic and mathematics by soundly and fully completely interpreting linear logic while fully and concretely embedding a comprehensive range of concrete categories of mathematics. Our main goal is to treat each end of this bridge in expository detail. In addition, we introduce the dialectic lambda-calculus, and show that dinaturality semantics is not fully complete for the Chu interpretation of linear logic.
A fast algorithm for the maximum clique problem
Authors: Patric R. J. Östergård
Venue: Discrete Applied Mathematics (2002)

Given a graph, in the maximum clique problem, one desires to find the largest number of vertices, any two of which are adjacent. A branch-and-bound algorithm for the maximum clique problem--which is computationally equivalent to the maximum independent (stable) set problem--is presented with the vertex order taken from a coloring of the vertices and with a new pruning strategy. The algorithm performs successfully for many instances when applied to random graphs and DIMACS benchmark graphs.
The lower bound of the number of non-overlapping triangles
Authors: Changqing Xu, Ren Ding
Venue: The Korean Journal of Computational Applied Mathematics (2003)

András Bezdek proved that if a convex n-gon and n points are given, then the points and the sides of the polygon can be renumbered so that at least ⌊/n3;⌋ triangles spanned by the ith point and the ith side (i = 1, 2,... n) are mutually non-overlapping. In this paper, we show that at least ⌈/n/2;⌉ mutually non-overlapping triangles can be constructed. This lower bound is best possible.
Path seeds and flexible isosurfaces using topology for exploratory visualization
Authors: Hamish Carr, Jack Snoeyink
Venue: Proceedings of the symposium on Data visualisation 2003 (2003)

Morse theory and the Reeb graph give topological summaries of the behaviour of continuous scalar functions. The contour tree augments the Reeb graph for the isosurfaces in a volume to store seed sets, which are starting points for extracting isosurfaces by the continuation method. We replace the minimal seed sets of van Kreveld et al. with path seeds, which generate paths that correspond directly to the individual components of an isosurface. From a path we get exactly one seed per component, which reduces storage and simplifies isosurface extraction. Moreover, the correspondence allows us to extend the contour spectrum of Bajaj et al. to an interface that we call flexible isosurfaces, in which individual contours with different isovalues can be displayed, manipulated and annotated. The largest contour segmentation, in which separate surfaces are generated for each local maximum of the field, is a special case of the flexible isosurface.
VR on a budget: developing a flight simulator in a small institution with off-the-shelf hardware and open source software
Authors: Joseph Dumas, Andrew Novobilski, Dawn Ellis, Mark Paschal
Venue: Journal of Computing Sciences in Colleges (2002)

One of the advantages of large, research-oriented institutions is the availability of leading-edge projects in which faculty may involve students. Faculty at smaller colleges and universities face significant challenges in finding meaningful research projects. Some of the difficulties may include a shortage of graduate students, a lack of hardware and software resources, and limited funding. An innovative applied research project in flight simulation at the University of Tennessee at Chattanooga involved the development of a virtual reality Space Shuttle landing simulation to help educate elementary and middle school students about space flight. This project addressed the above concerns by involving undergraduate as well as master's students in the project, by tapping private foundation funding, and by using off-the-shelf hardware and open-source software as a basis for the project. By adopting this approach we were able to develop an interesting and technically challenging project with benefits for the simulation users as well as the faculty and students involved, thus taking advantage of a type of educational opportunity which might not otherwise be available at a small institution.
Performance of multihop wireless networks: shortest path is not enough
Authors: Douglas S. J. De Couto, Daniel Aguayo, Benjamin A. Chambers, Robert Morris
Venue: ACM SIGCOMM Computer Communication Review (2003)

Existing wireless ad hoc routing protocols typically find routes with the minimum hop-count. This paper presents experimental evidence from two wireless test-beds which shows that there are usually multiple minimum hop-count paths, many of which have poor throughput. As a result, minimum-hop-count routing often chooses routes that have significantly less capacity than the best paths that exist in the network. Much of the reason for this is that many of the radio links between nodes have loss rates low enough that the routing protocol is willing to use them, but high enough that much of the capacity is consumed by retransmissions. These observations suggest that more attention be paid to link quality when choosing ad hoc routes; the paper presents measured link characteristics likely to be useful in devising a better path quality metric.
An n! lower bound on formula size
Authors: Micah Adler, Neil Immerman
Venue: ACM Transactions on Computational Logic (TOCL) (2003)

We introduce a new Ehrenfeucht--Fra&iuml;ss&eacute; game for proving lower bounds on the size of first-order formulas. Up until now, such games have only been used to prove bounds on the operator depth of formulas, not their size. We use this game to prove that the CTL+ formula, Occurn &equiv; E[Fp1 &and; Fp2 &and; &hellip; &and; Fpn], which says that there is a path along which the predicates p1 through pn all occur, requires size n! to express in CTL. Our lower bound is optimal. It follows that the succinctness of CTL+ with respect to CTL is exactly &Theta;(n)!. Wilke had shown that the succinctness was at least exponential [Wilke 1999].We also use our games to prove an optimal &Omega;(n) lower bound on the number of boolean variables needed for forward reachability logic (RLf) to polynomially embed the language CTL+. The number of booleans needed for full reachability logic RL and the transitive closure logic FO2(TC) remain open [Immerman and Vardi 1997; Alechina and Immerman 2000].
Efficient non-repudiation multicast source authentication schemes
Authors: Xianxian Li, Jinpeng Huai
Venue: Journal of Computer Science and Technology (2002)

In secure multicast communication, packet source authentication is a bottleneck problem due to the dynamic property of the multicast group, unreliability of data transmission and the large number of data packets. This paper proposes a novel authentication scheme called B-MSAS (Balance Multicast Source Authentication Scheme) that can be used to solve this problem, in which a new message authentication technique is introduced. This scheme dramatically reduces the signature size overhead and raises the signature rate. It provides the non-repudiation service, high loss resistance, and can easily be scaled up to potentially millions of receivers, and hence has a sweeping applicability. It should have applications to many practical problems.
A Scaling Algorithm for Multicommodity Flow Problems
Authors: Rina R. Schneur, James B. Orlin
Venue: Operations Research (1998)

We present a penalty-based algorithm that solves the multicommodity flow problem as a sequence of a finite number of scaling phases. The basis of the algorithm is simple and consists of iteratively detecting and sending flow around negative cost cycles. Two parameters control the algorithm's behavior: the penalty parameter and the scaling parameter. In the &#949;-scaling phase, where &#949; is a function of the penalty and scaling parameters, the algorithm determines an &#949;-optimal solution; a solution in which complementary slackness conditions are satisfied to within &#949;. We analyze the performance of the algorithm from both the theoretical and practical perspectives. The computational results support the theoretical behavior of the algorithm. They also demonstrate the efficiency of the algorithm for solving problem instances of different structure and size.
Octane: A New Heuristic for Pure 0-1 Programs
Authors: Egon Balas, Sebastián Ceria, Milind Dawande, Francois Margot, Gábor Pataki
Venue: Operations Research (2001)

We propose a new heuristic for pure 0-1 programs, which finds feasible integer points by enumerating extended facets of the octahedron, the outer polar of the unit hypercube. We give efficient algorithms to carry out the enumeration, and we explain how our heuristic can be embedded in a branch-and-cut framework. Finally, we present computational results on a set of pure 0-1 programs taken from MIPLIB and other sources.
Integrating timed condition/event systems and timed automata for the verification of hybrid systems
Authors: R. Huuck, Y. Lakhnech, B. Lukoschus, L. Urbina, S. Engell, S. Kowalewski, J. Preußig
Venue: Engineering of distributed control systems (2001)

In this paper we integrate two different approaches for the specification and verification of timed systems being used in control theory and computer science. These are the timed condition/event systems and the timed automata formalisms. Our main result states that timed condition/event systems can be efficiently transformed into timed automata which then can be analyzed automatically.
Comparison of group screening strategies for factorial experiments
Authors: A. M. Dean, S. M. Lewis
Venue: Computational Statistics Data Analysis (2002)

Factor screening is an important first step in many industrial experiments where a large number of factors potentially influence a response. The purpose of screening is to identify those few factors which have a substantive influence (that is, are active) and therefore, require further investigation. This paper provides a simulation tool for comparing two-stage group screening strategies where both design and noise factors may be under study. The strategies investigated are classical group screening, in which only main effects are considered at the first stage of the experiment, and an alternative strategy of screening for two-factor interactions as well as main effects.An algorithm is described which allows the user to simulate, and hence to compare, the strategies under different selections of designs and different group sizes for the stage 1 experiment, and for different probabilities of active effects. A detailed example of the use of the algorithm shows how an appropriate strategy can be chosen based on two criteria. These criteria consider the proportion of active factorial effects that are incorrectly screened out at the first-stage experiment, and the average number of observations needed for the entire experiment.
The Censored Newsvendor and the Optimal Acquisition of Information
Authors: Xiaomei Ding, Martin L. Puterman, Arnab Bisi
Venue: Operations Research (2002)

This paper investigates the effect of demand censoring on the optimal policy in newsvendor inventory models with general parametric demand distributions and unknown parameter values. We show that the newsvendor problem withobservable lost sales reduces to a sequence of single-period problems, while the newsvendor problem withunobservable lost sales requires a dynamic analysis. Using a Bayesian Markov decision process approach we show that the optimalin ventory level in the presence of censored demand ishigher than would be determined using a Bayesian myopic policy. We explore the economic rationality for this observation and illustrate it with numerical examples.