ppxscal/embedding_network huggingface dataset:
A Combined Physical and Statistical Approach to Colour Constancy
Authors: Gerald Schaefer, Steven Hordley, Graham Finlayson
Venue: Proceedings of the 2005 IEEE Computer Society Conference on Computer Vision and Pattern Recognition (CVPR'05) - Volume 1 - Volume 01 (2005)

Computational colour constancy tries to recover the colour of the scene illuminant of an image. Colour constancy algorithms can, in general, be divided into two groups: statistics-based approaches that exploit statistical knowledge of common lights and surfaces, and physics-based algorithms which are based on an understanding of how physical processes such as highlights manifest themselves in images. A combined physical and statistical colour constancy algorithm that integrates the advantages of the statistics-based Colour by Correlation method with those of a physics-based technique based on the dichromaticreflectance model is introduced. In contrast to other approaches not only a single illuminant estimate is provided but a set of likelihoods for a given illumination set. Experimental results on the benchmark Simon Fraser image database show the combined method to clearly out-perform purely statistical and purely physical algorithms.
Virtual Leashing: Internet-Based Software Piracy Protection
Authors: Ori Dvir, Maurice Herlihy, Nir N. Shavit
Venue: Proceedings of the 25th IEEE International Conference on Distributed Computing Systems (2005)

Software-splitting is a technique for protecting software from piracy by removing code fragments from an application and placing them on a remote trusted server. The server provides the missing functionality but never the missing code. As long as the missing functionality is hard to reverse-engineer, the application cannot run without validating itself to the server. Current software-splitting techniques scale poorly to the Internet because interactions with the remote server are synchronous: the application must frequently block waiting for a response from the server. Perceptible delays due to network latency are unacceptable for many kinds of highly-reactive applications, such as games or graphics applications. This paper introduces virtual leashing, the first non-blocking software-splitting technique. Virtual leashing ensures that the application and the server communicate asynchronously, so the applicationýs performance is independent (within reason) of large or variable network latencies. Experiments show that virtual leashing makes only modest demands on communication bandwidth, space, and computation.
Research at Xerox PARC
Authors: Ronald M. Kaplan
Venue: Issue 79 (January 1982) (1982)

The Xerox Palo Alto Research Center maintains a small, theoretically oriented natural language research program. The principal investigators are Ronald M. Kaplan (Cognitive and Instructional Sciences Group) and Martin Kay (Computer Science Laboratory). For the last several years, we have focussed on linguistic, psycholinguistic, and computational aspects of syntax and morphology.
Almost symplectic Runge-Kutta schemes for Hamiltonian systems
Authors: Xiaobo Tan
Venue: Journal of Computational Physics (2005)

Symplectic Runge-Kutta schemes for the integration of general Hamiltonian systems are implicit. In practice, one has to solve the implicit algebraic equations using some iterative approximation method, in which case the resulting integration scheme is no longer symplectic. In this paper, the preservation of the symplectic structure is analyzed under two popular approximation schemes, fixed-point iteration and Newton's method, respectively. Error bounds for the symplectic structure are established when N fixed-point iterations or N iterations of Newton's method are used. The implications of these results for the implementation of symplectic methods are discussed and then explored through numerical examples. Numerical comparisons with non-symplectic Runge-Kutta methods and pseudo-symplectic methods are also presented.
Fully procedural graphics
Authors: T. Whitted, J. Kajiya
Venue: Proceedings of the ACM SIGGRAPH/EUROGRAPHICS conference on Graphics hardware (2005)

The growing application of user-defined programs within graphics processing units (GPUs) has transformed the fixed-function display pipeline into a largely programmable pipeline. In this paper we propose that the elements fed through the pipeline be made entirely procedural. To enable this, we present a modification of the conventional graphics processor in which all procedures are executed in a common processor array and the rasterizer is augmented with a more general sampling controller. By executing both the geometric and shading elements of a procedural graphics model in a single processor we retain the data amplification that distinguishes procedural descriptions without a corresponding explosion of external bandwidth.
Integrating tools and resources: a case study in building educational groupware for collaborative programming
Authors: John T. Langton, Timothy J. Hickey, Richard Alterman
Venue: Journal of Computing Sciences in Colleges (2004)

This paper presents design implications for educational groupware as revealed by GHT (Group Homework Tool), a same time different place groupware tool built to support synchronous, collaborative coding among novice programmers. We detail the design, implementation, evaluation, and redesign of GHT, focusing on the issues of awareness, control, evaluation and scaffolding. GHT capitalizes on trends of technology and collaboration in the traditional learning environment by supporting distance learning, remote access to TAs and tutors, and facilitating co-located and remote group work. Constructing such software for a computer science curriculum provides unique challenges as one must integrate the tools used by a programmer, the resources used by a learner, and the widgets used to support group interaction. By combining common groupware components with our own shared editor we were able to exploit the educational benefits in a modified version of extreme programming [1]. Our research informs future design efforts by building upon previous investigations of integrated, cooperative software in a learning environment [11, 13, 12].
AURALIZATION OF PARALLEL PROGRAMS
Authors: Larry Albright, Jay Alan Jackson, Joan Francioni
Venue: ACM SIGCHI Bulletin (1991)

Auralization is the sonic equivalent of visualization. It is the attempt to convey the essence of massive amounts of scientific data in a manner that can be easily interpreted by humans. Visualization appeals to human sight, auralization appeals to human hearing.
Sticky widgets: pseudo-haptic widget enhancements for multi-monitor displays
Authors: Regan L. Mandryk, Malcolm E. Rodgers, Kori M. Inkpen
Venue: CHI '05 extended abstracts on Human factors in computing systems (2005)

People use multiple monitors to increase their display surface and to facilitate multitasking. However, if windows are maximized to fill one screen, users may have difficulties accessing widgets and tools on the borders of the displays, accidentally crossing over to the other display. To assist users of multi monitor displays, we developed a pseudo-haptic approach to enhance boundary widgets. We compared our sticky widget to a standard widget for two multi monitor display configurations: two identical side-by-side monitors, and two separated monitors of different sizes. Our enhancement improved performance by significantly reducing errors for accessing a boundary widget, reducing the number of accidental crossovers to the wrong display and consequently decreasing selection time.
Level Set Evolution without Re-Initialization: A New Variational Formulation
Authors: Chunming Li, Chenyang Xu, Changfeng Gui, Martin D. Fox
Venue: Proceedings of the 2005 IEEE Computer Society Conference on Computer Vision and Pattern Recognition (CVPR'05) - Volume 1 - Volume 01 (2005)

In this paper, we present a new variational formulation for geometric active contours that forces the level set function to be close to a signed distance function, and therefore completely eliminates the need of the costly re-initialization procedure. Our variational formulation consists of an internal energy term that penalizes the deviation of the level set function from a signed distance function, and an external energy term that drives the motion of the zero level set toward the desired image features, such as object boundaries. The resulting evolution of the level set function is the gradient flow that minimizes the overall energy functional. The proposed variational level set formulation has three main advantages over the traditional level set formulations. First, a significantly larger time step can be used for numerically solving the evolution partial differential equation, and therefore speeds up the curve evolution. Second, the level set function can be initialized with general functions that are more efficient to construct and easier to use in practice than the widely used signed distance function. Third, the level set evolution in our formulation can be easily implemented by simple finite difference scheme and is computationally more efficient. The proposed algorithm has been applied to both simulated and real images with promising results.
Agent-Based Modelling: A Case Study in HIV Epidemic
Authors: Eyob Teweldemedhin, Tshilidzi Marwala, Conrad Mueller
Venue: Proceedings of the Fourth International Conference on Hybrid Intelligent Systems (2004)

This research presents an agent-based, bottom-up modelling approach to develop a simulation tool for estimating and predicting the spread of the Human Immunodeficiency Virus (HIV) in a given population. HIV is mainly a sexually transmitted disease (STD) causing a serious problem to human health. The virus is transmitted from an infected person to another who was previously healthy through different biological, social and environmental factors. The research develops the simulation tool by modelling these factors by agents. Although research has and is being conducted to estimate and predict the spread of the HIV epidemic, the proposed research seeks to investigate the spread using a different approach. The previous models used a top-down modelling approach. They are built from the general characteristics and behaviours of the population. They have not explored the potential use of agent technology. This research attempts to investigate the flexibility that the multiagent system offers. Agent-based models are close to the situations that exist in a given real system that consists of autonomous components interacting with each other. The modelling approach has the advantage of observing the interaction made between agents, which is a difficult task in the top-down modelling approach. The research investigates the performance of the tool and presents the first results obtained.
Complexity Reduction in Lattice-Based Information Retrieval
Authors: Karen S. Cheung, Douglas Vogel
Venue: Information Retrieval (2005)

Though lattice-based information representation has the advantage of providing efficient visual interface over textual display, the complexity of a lattice may grow rapidly with the size of the database. In this paper we formally draw the analogy between Vector Space Model and Concept Lattice, from which we introduce the notion of Term-Document Lattice as a model for information retrieval. We then propose to use the idea of quotient lattice to reduce the complexity of a Term-Document Lattice. The equivalence relation required to construct the quotient lattice is obtained by performing a Singular Value Decomposition on the original term-document matrix.
Efficient sampling schemes for Bayesian MARS models with many predictors
Authors: David J. Nott, Anthony Y. Kuk, Hiep Duc
Venue: Statistics and Computing (2005)

Multivariate adaptive regression spline fitting or MARS (Friedman 1991) provides a useful methodology for flexible adaptive regression with many predictors. The MARS methodology produces an estimate of the mean response that is a linear combination of adaptively chosen basis functions. Recently, a Bayesian version of MARS has been proposed (Denison, Mallick and Smith 1998a, Holmes and Denison, 2002) combining the MARS methodology with the benefits of Bayesian methods for accounting for model uncertainty to achieve improvements in predictive performance. In implementation of the Bayesian MARS approach, Markov chain Monte Carlo methods are used for computations, in which at each iteration of the algorithm it is proposed to change the current model by either (a) Adding a basis function (birth step) (b) Deleting a basis function (death step) or (c) Altering an existing basis function (change step). In the algorithm of Denison, Mallick and Smith (1998a), when a birth step is proposed, the type of basis function is determined by simulation from the prior. This works well in problems with a small number of predictors, is simple to program, and leads to a simple form for Metropolis-Hastings acceptance probabilities. However, in problems with very large numbers of predictors where many of the predictors are useless it may be difficult to find interesting interactions with such an approach. In the original MARS algorithm of Friedman (1991) a heuristic is used of building up higher order interactions from lower order ones, which greatly reduces the complexity of the search for good basis functions to add to the model. While we do not exactly follow the intuition of the original MARS algorithm in this paper, we nevertheless suggest a similar idea in which the Metropolis-Hastings proposals of Denison, Mallick and Smith (1998a) are altered to allow dependence on the current model. Our modification allows more rapid identification and exploration of important interactions, especially in problems with very large numbers of predictor variables and many useless predictors. Performance of the algorithms is compared in simulation studies.
Decomposition and virtualization of eigenface for face recognition under various lighting conditions
Authors: Kazuma Shigenari, Fumihiko Sakaue, Takeshi Shakunaga
Venue: Systems and Computers in Japan (2005)

It is intended in this paper to construct a recognition method that is more robust against changes of lighting conditions than the conventional method. The method applies orthogonal decomposition and virtualization to the eigenface within the framework of the subspace method. The eigenface is derived by applying principal component analysis (eigenvalue decomposition) to the set of face images for each person under various lighting conditions. In the proposed method, the standard face eigenspace (canonical space) is used, and the face image is orthogonally decomposed into the projection component, which is affected mostly by the lighting variation, and the residual component, which contains other aspects of personality and noise. By analyzing the residual component, the noise component in the input image is eliminated. By the above approach, the eigenspace (eigen-projection) containing the standard face information, and the eigenspace (eigen-residual) containing the individuality, are constructed. To the eigen-projection, the concept of the virtual subspace is applied, and the virtual eigen-projection is constructed. With this procedure, stable recognition is realized using the subspace method, even if only a small number of images (as few as one) are registered. &copy; 2004 Wiley Periodicals, Inc. Syst Comp Jpn, 36(1): 25&ndash;34, 2005; Published online in Wiley InterScience (). DOI 10.1002&sol;scj.10638
First Fredkin challenge match
Authors: Hans Berliner
Venue: Issue 73 (October 1980) (1980)

On August 18 and 19, at Stanford University during the AAAI conference, the first of a projected pair of annual chess competitions pitting the World's best computer programs against rated human players of approximately the same strength was held. These matches are part of the Fredkin prize competition, wherein a sum of $100,000, established by the Fredkin Foundation of Cambridge, Massachusetts, is ultimately to be awarded to the creators of a program that will defeat the World Chess Champion in official competition.
Approximations of Shape Metrics and Application to Shape Warping and Empirical Shape Statistics
Authors: Guillaume Charpiat, Olivier Faugeras, Renaud Keriven
Venue: Foundations of Computational Mathematics (2005)

This paper proposes a framework for dealing with several problems related to the analysis of shapes. Two related such problems are the definition of the relevant set of shapes and that of defining a metric on it. Following a recent research monograph by Delfour and Zol&#x00e9;sio [11], we consider the characteristic functions of the subsets of R2 and their distance functions. The L2 norm of the difference of characteristic functions, the L&#x221e; and the W1,2 norms of the difference of distance functions define interesting topologies, in particular the well-known Hausdorff distance. Because of practical considerations arising from the fact that we deal with image shapes defined on finite grids of pixels, we restrict our attention to subsets of &#x211d;2 of positive reach in the sense of Federer [16], with smooth boundaries of bounded curvature. For this particular set of shapes we show that the three previous topologies are equivalent. The next problem we consider is that of warping a shape onto another by infinitesimal gradient descent, minimizing the corresponding distance. Because the distance function involves an inf, it is not differentiable with respect to the shape. We propose a family of smooth approximations of the distance function which are continuous with respect to the Hausdorff topology, and hence with respect to the other two topologies. We compute the corresponding G&#x00e2;teaux derivatives. They define deformation flows that can be used to warp a shape onto another by solving an initial value problem.We show several examples of this warping and prove properties of our approximations that relate to the existence of local minima. We then use this tool to produce computational definitions of the empirical mean and covariance of a set of shape examples. They yield an analog of the notion of principal modes of variation. We illustrate them on a variety of examples.
Robust Object Detection via Soft Cascade
Authors: Lubomir Bourdev, Jonathan Brandt
Venue: Proceedings of the 2005 IEEE Computer Society Conference on Computer Vision and Pattern Recognition (CVPR'05) - Volume 2 - Volume 02 (2005)

We describe a method for training object detectors using a generalization of the cascade architecture, which results in a detection rate and speed comparable to that of the best published detectors while allowing for easier training and a detector with fewer features. In addition, the method allows for quickly calibrating the detector for a target detection rate, false positive rate or speed. One important advantage of our method is that it enables systematic exploration of the ROC Surface, which characterizes the trade-off between accuracy and speed for a given classifier.
On the design of a user interface to large Fortran subroutine packages under IBM 360/370 OS
Authors: A. Tweedale, C. Chan
Venue: ACM SIGNUM Newsletter (1975)

An often encountered inconvenience when one uses a large subroutine package (e.g. IBMSSP) is that one faces the problem of selecting the proper subroutines in the proper sequence to execute the proper computation. This at times is difficult if not prohibitive because the algorithms employed by the subroutines are sophisticated and beyond the comprehension of the user. When this happens, the subroutine package becomes a frustration as much as a useful tool to the user. It is therefore desirable to split up such large subroutine packages into chapters of subroutines according to their functions and create control routines for each chapter. The purpose of these control routines is to interpret the arguments supplied by the user and then invoke the proper subroutines in the proper sequence for the computational solution.
Approximation results for a bicriteria job scheduling problem on a single machine without preemption
Authors: Eric Angel, Evripidis Bampis, Laurent Gourvès
Venue: Information Processing Letters (2005)

We study the problem of minimizing the average weighted completion time on a single machine under the additional constraint that the sum of completion times does not exceed a given bound B (1|Σ Cj ≤ B|ΣwjCj) for which we propose a (2, 1)-approximation algorithm. We also address the problem 1|ΣcjCj ≤ B|ΣwjCj for which we present a (2, 2)- approximation algorithm. After showing that the problem of minimizing two different sums of weighted completion times is intractable, we present an algorithm which computes a (2(1 + ε), 1) (respectively (2(1 + ε), 2))-approximate Pareto curve for the problem 1||(ΣCj, ΣwjCj) (respectively 1||(ΣcjCj, ΣwjCj)).
Algorithms for optimal partial matching of free-form objects with scaling effects
Authors: K. H. Ko, T. Maekawa, N. M. Patrikalakis
Venue: Graphical Models (2005)

A free-form object matching problem is addressed in this paper. Two methods are proposed to solve a partial matching problem with scaling effects and no prior information on correspondence or the rigid body transformation involved. The first method uses umbilical points, which behave as fingerprints of a surface and their qualitative properties can be used for matching purposes. The second method uses an optimization scheme based on the extension of the KH curvature matching method [Comput. Aided Design 35 (2003) 913], first introduced in the context of a matching problem without scaling effects. Two types of curvatures, the Gaussian and the mean curvatures, are used to establish correspondences between two objects. The curvature matching method is formulated in terms of minimization of an objective function depending on the unknown scaling factor, and the rigid body transformation parameters. The accuracy and complexity of the proposed methods as well as the convergence for the optimization approach are analyzed. Examples illustrate the two methods.
Comparative Study of Unsharp Masking Methods for Image Enhancement
Authors: M. A. Badamchizadeh, A. Aghagolzadeh
Venue: Proceedings of the Third International Conference on Image and Graphics (2004)

Contrast enhancement by the unsharp masking (UM) approaches are the simplest methods, both computationally and conceptually. In this paper, different methods of UM for image enhancement are compared. These algorithms have been tested and compared for the same conditions. The results show the majority of these algorithms are very sensitive to enhancement factor; and for good sharpening, this factor must be estimated recursively by considering the statistics of neighboring pixel values.
Special Issue: Learning and creativity Part 1
Authors: Alex H. B. Duffy, Frances M. T. Brazier
Venue: Artificial Intelligence for Engineering Design, Analysis and Manufacturing (2004)

Special Issue Part 1 (Issue 3) and Part 2 (Issue 4) of AIEDAM are based on a workshop on Learning and Creativity held at the 2002 conference on Artificial Intelligence in Design, AID '02 (www.cad.strath.ac.uk&sol;AID02_workshop&sol;Workshop_webpage.html; Gero, 2002). It was the sixth of similar workshops, with the previous five focusing on Machine Learning in Design and being held at AIDs '92, '94, '96, '98, and '00 (Gero, 1992, 2000; Gero & Sudweeks, 1994, 1996, 1998). The first three workshops also resulted in special issues of AIEDAM (Maher et al., 1994; Duffy et al., 1996, 1998).