ppxscal/embedding_network huggingface dataset:
Statistical Cue Integration in DAG Deformable Models
Authors: Siome Klein Goldenstein, Christian Vogler, Dimitris Metaxas
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (2003)

Deformable models are a useful modeling paradigm in computer vision. A deformable model is a curve, a surface, or a volume, whose shape, position, and orientation are controlled through a set of parameters. They can represent manufactured objects, human faces and skeletons, and even bodies of fluid. With low-level computer vision and image processing techniques, such as optical flow, we extract relevant information from images. Then, we use this information to change the parameters of the model iteratively until we find a good approximation of the object in the images. When we have multiple computer vision algorithms providing distinct sources of information (cues), we have to deal with the difficult problem of combining these, sometimes conflicting contributions in a sensible way. In this paper, we introduce the use of a directed acyclic graph (dag) to describe the position and Jacobian of each point of deformable models. This representation is dynamic, flexible, and allows computational optimizations that would be difficult to do otherwise. We then describe a new method for statistical cue integration method for tracking deformable models that scales well with the dimension of the parameter space. We use affine forms and affine arithmetic to represent and propagate the cues and their regions of confidence. We show that we can apply the Lindeberg theorem to approximate each cue with a Gaussian distribution, and can use a maximum-likelihood estimator to integrate them. Finally, we demonstrate the technique at work in a 3D deformable face tracking system on monocular image sequences with thousands of frames.
Toward the Optimal Preconditioned Eigensolver:Locally Optimal Block Preconditioned Conjugate Gradient Method
Authors: Andrew V. Knyazev
Venue:  (2000)

We describe new algorithms of the Locally Optimal Block Preconditioned Conjugate Gradient (LOBPCG) Method for symmetric eigenvalue problems, based on a local optimization of a three-term recurrence. To be able to compare numerically different methods in the class, with different preconditioners, we suggest a common system of model tests, using random preconditioners and initial guesses. As the ``ideal'''' control algorithm, we propose the standard preconditioned conjugate gradient method for finding an eigenvector as an element of the null--space of the corresponding homogeneous system of linear equations under the assumption that the eigenvalue is known. We recommend that every new preconditioned eigensolver be compared with this ``ideal'''' algorithm on our model test problems in terms of the speed of convergence, costs of every iterations and memory requirements. We provide such comparison for our LOBPCG Method. Numerical results establish that our algorithm is practically as efficient as the ``ideal'''' algorithm when the same preconditioner is used in both methods. We also show numerically that the LOBPCG Method provides approximations to first eigenpairs of about the same quality as those by the much more expensive global optimization method on the same generalized block Krylov subspace. Finally, direct numerical comparisons with the Jacobi--Davidson method show that our method is more robust and converges almost two times faster.
Efficient Approximation Algorithms for Some Semidefinite Programs
Authors: Hsueh Lu
Venue:  (1996)

Linear programming has been fruitful in designing approximation algorithms for many combinatorial optimization problems. Nonlinear programming did not receive as much attention in this respect until the recent work by Goemans and Williamson. They use {\em semidefinite programs} to obtain approximation solutions with much better approximation factors. For example, the best previously known approximation algorithm for MAXCUT, which was invented twenty years ago, has approximation factor 0.5. The algorithm of Goemans and Williamson dramatically improves the approximation factor to 0.878. Inspired by the work on MAXCUT, Karger, Motwani, and Sudan adapt the same technique and obtain the currently best approximation algorithm for coloring a $k$-colorable graph with the fewest possible number of colors. The approximation ratio is improved by a factor of $\Omega(n^{2/k})$ over the best previously known result. Besides MAXCUT and COLORING, the technique of semidefinite programming has been successful in designing approximation algorithms for many other optimization problems. Each of these improved algorithms is based on obtaining a near-optimal solution to a semidefinite program, which is referred as the {\em semidefinite relaxation} of the underlining optimization problem. Therefore how to approximately solve these semidefinite relaxations efficiently, in both time and space, is practically important. All the previous work resorts to {\em interior-point methods} for this step. In the thesis the framework of Plotkin, Shmoys, and Tardos is adapted to obtain near-optimal solutions to the semidefinite relaxations of MAXCUT and COLORING. The results significantly reduce the work space required by the best known approximation algorithms for MAXCUT and COLORING if the given graph is sparse. As a consequence, the results in the thesis enable the best known approximation algorithms for MAXCUT and COLORING to work on much larger sparse graphs than they did with interior-point methods. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
Enabling Snap-Stabilization
Authors: Alain Cournier, Ajoy K. Datta, Franck Petit, Vincent Villain
Venue: Proceedings of the 23rd International Conference on Distributed Computing Systems (2003)

A snap-stabilizing protocol guarantees that the systemalways behaves according to its specification provided someprocessor initiated the protocol. We present how to snap-stabilizesome important protocols, like Leader Election,Reset, Snapshot, and Termination Detection.WeuseaSnap-stabilizing Propagation of Information with Feedbackprotocol for arbitrary networks as the key module in theabove transformation process. Finally, we design a universaltransformer to provide a snap-stabilizing version of anyprotocol (which can be self-stabilized with the transformerof [15]).
Linear-Processor NC Algorithms For Planar Directed Graphs I: Strongly Connected Components
Authors: Ming Kao
Venue:  (1989)

Finding strongly connected components is a fundamental step in many algorithms for directed graphs. In sequential computation, this problem has an optimal linear-time algorithm. In parallel computation, however, it remains an open problem whether polylog time and {\em linear} processors are sufficient for computing strongly connected components on a parallel random access machine. This paper provides the first nontrivial partial solution to this open problem: For a planar directed graph with $n$ vertices, the strongly connected components can be found in $0(log^3~n)$ time and $0(n)$ processors. The algorithm is deterministic and runs on a parallel random access machine that allows concurrent reads and concurrent writes in its shared memory. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
An Architecture for Adaptively Replicating Cooperative Shared Objects
Authors: Zhu Jun Yu Yong
Venue: Proceedings of the Fifth International Symposium on Autonomous Decentralized Systems (2001)

The static data-sharing model employed by most nowadays groupware systems is not fit for the dynamic nature of today's cooperative environments. We present in this paper a dynamic replica distribution model, which replicates shared objects replicas adaptively according to user requirement as well as dynamic cooperation context. A replicating structure between fully-replicated and fully-centralized ones is achieved through the process of structural adaptation; concurrency adaptation is also used to achieve a multi-replica consistency policy between traditional optimistic and pessimistic paradigms. XML is used as the underlying support layer for representing the structures and contents of shared cooperative objects
A Browsing System for a Database Using Visualization of User Preferences
Authors: Hideaki Kanai
Venue: Proceedings of the International Conference on Information Visualisation (2000)

This paper describes a browsing system for a database using visualization of user preferences. The system has the following features: (1) The use of 3D thumbnail objects to represent their contents and properties, (2) The use of some property views and multidimensional scaling (MDS) to lay out the objects in information space, and (3) The use of update mechanism to perform the adaptive visualization to changes in user preferences. In this environment, the user becomes aware that there are information sets, which the user seems to be interested in, from objects in information space, and stroll there.
The Witnessential Net
Authors: Steve Mann, Robert Guerra
Venue: Proceedings of the 5th IEEE International Symposium on Wearable Computers (2001)

The Witnessential Network for the protection of Human Rights workers,and others who may be subjected to violence,is achieved through a new kind of imaging and hierarchical architecture having special properties ideal for defense against unaccountability of attackers. Incidentalist video capture and self-demotion are introduced as new collegial f rms f defense against unac- countability.Results of various experiments conducted worldwide ver the past 20 years, on the inventing,designing,building,and using of wearable photographic apparatus having these special properties are also described.Other fundamental concepts with respect to a Personal Safety Device suitable for Human Rights workers are introduced.
Relationship between UCHT and FFT
Authors: Shoulie Xie, Susanto Rahardja, Zhenghui Gu
Venue: Proceedings of the 33rd International Symposium on Multiple-Valued Logic (2003)

This paper presents relationships among unified complexHadamard transform (UCHT) whose transformation matrixcontains elements \pm1 and \pmi, Walsh-Hadamard transform(WHT) whose transformation matrix contains elements \pm1,and Fast Fourier Transform (FFT). They are all related toeach other by a key matrix, and FFT can be computed byusing UCHT, WHT and some twiddle factor matrices.
Veronese varieties over fields with non-zero characteristic: a survey
Authors: Hans Havlicek
Venue: Discrete Mathematics (2003)

A subspace in the ambient space of a Veronese variety is said to be invariant if it is fixed (as a set of points) under the group of automorphic collineations of the variety. Among the invariant subspaces are the nuclei of Veronesean; they arise as intersection of all osculating subspaces of a fixed type. Here we give a survey on recent results about nuclei of Veronese varieties and invariant subspaces of normal rational curves. If the characteristic of the ground field is zero, then there are only the trivial invariant subspaces. If the characteristic is a prime p, then there are in general many such subspaces, and there is a close relationship to the array of multinomial coefficients module p.
Non-linear subdivision using local spherical coordinates
Authors: Nicolas Aspert, Touradj Ebrahimi, Pierre Vandergheynst
Venue: Computer Aided Geometric Design (2003)

In this paper, we present an original non-linear subdivision scheme suitable for univariate data, plane curves and discrete triangulated surfaces, while keeping the complexity acceptable. The proposed technique is compared to linear subdivision methods having an identical support. Numerical criteria are proposed to verify basic properties, such as convergence of the scheme and the regularity of the limit function.
On the Design of Communication-Aware Task Scheduling Strategies for Heterogeneous Systems
Authors: J. M. Orduña, V. Arnau, A. Ruiz, R. Valero, José Duato
Venue: Proceedings of the Proceedings of the 2000 International Conference on Parallel Processing (2000)

Many research activities have focused on the problem of task scheduling in heterogeneous systems from the computational point of view. However, an ideal scheduling strategy would also take into account the communication requirements of the applications and the communication bandwidth that the network can offer. In this paper, we first propose a criterion to measure the suitability of each allocation of network resources to each parallel application, according to the communication requirements. Second, we propose a scheduling technique based exclusively on a criterion that provides a near-optimal mapping of processes to processors according to the communication requirements. Evaluation results show that the use of this scheduling technique fully exploits the available network bandwidth, greatly improving network performance. Therefore, the proposed scheduling technique may be used in the design of communication-aware scheduling strategies for those situations where the communication requirements are the system performance bottleneck.
Several remarks on the complexity of set-valued switching functions
Authors: D. A. Simovici, C. Reischer
Venue: Proceedings of the 26th International Symposium on Multiple-Valued Logic (1996)

We explore the complexity of circuits that implement set-valued logic functions on a complete basis that we propose in this paper. This basis is related to the bases used in the main sources on this subject, as we show in Section 2. After discussing properties of the constituents of this basis (which consist of both Boolean and non-Boolean components) we prove that almost all set-valued functions require a large number of Boolean components.
LINK: A Combinatorics and Graph Theory Workbench for Applications and Research
Authors: J. Berry, N. Dean, P. Fasel, M. Goldberg, E. Johnson, J. MacCuish, G. Shannon, S. Skiena
Venue:  (1995)

LINK is a set of C++ class libraries that supports applications in discrete mathematics. The libraries include a commandline interpreter and a graphical user interface that allow access to basic data structures such as \Sets\ and \Lists, and a graph hierarchy that includes undirected, directed, and ``mixed'''' graph may contain both directed and undirected edges. Many standard data structures including arrays, lists, heaps and binary search trees are within a \Container\ hierarchy. \Sets\ and \Sequences\ are supported within a \Collection\ hierarchy. The data structure hierarchies enable the user to experiment with competing data structure implementations, and with more complex and sophisticated data structures. If an algorithm has several possible choices of a data structure to be used, a single object can be created that is templated with the particular data structure desired. LINK also contains a set of graph generators, layout algorithms for hypergraphs and binary graphs, and numerous graph algorithms. Interactive visulation of hypergraphs, graphs, and subgraphs is included in LINKGUI, the research tool application for combinatorics and graph theory built on top of the LINK libraries. LINKGUI is a collection of libraries that includes a Motif-based graphical user interface and Tcl-based command-line interface. The ability to select, contract and expand subgraphs and nested subgraphs in either hypergraphs or binary graphs is included in LINKGUI. LINKGUI enables a user to perform unary operations, such as complement, on a particular graph or to combine graphs via binary operations such as graph union or intersection. The resulting graphs can be displayed in multiple windows. Algorithms can be run on graphs where subgraphs have been contracted into single vertices. Other LINK applications can be developed by using various parts of the library code and adding code specific to the application. This new code can include an entirely different interface from that supplied by LINKGUI.
Fast Neural Networks for Domain Decomposition in Finite Element Analysis
Authors: Sugata Ghosal, Jan Mandel, Radek Tezaur
Venue:  (1994)

The solution of large finite element problems on distributed memory (even shared virtual memory) computers calls for efficient partitioning of large and unstructured 3-D meshes into submeshes such that computations can be distributed across processors. It is desired that resulting subdomains (submeshes) are approximately of same size, and the total number of interface nodes between adjacent subdomains is minimal. Two fine-grain scalable parallel algorithms are proposed employing neural network paradigms that can efficiently perform mesh partitioning for subsequent domain decomposition computations. New implementations are developed such that both the techniques have almost linear complexity with respect to the problem size for serial execution. These substructuring techniques compare favorably to the well-known recursive spectral bisection (RSB) method and simulated annealing- based partitioning algorithm.
Software Fault Tolerance of Distributed Programs Using Computation Slicing
Authors: Neeraj Mittal, Vijay K. Garg
Venue: Proceedings of the 23rd International Conference on Distributed Computing Systems (2003)

Writing correct distributed programs is hard. In spite ofextensive testing and debugging, software faults persist evenin commercial grade software. Many distributed systems,especially those employed in safety-critical environments,should be able to operate properly even in the presence ofsoftware faults. Monitoring the execution of a distributedsystem, and, on detecting a fault, initiating the appropriatecorrective action is an important way to tolerate such faults.This gives rise to the predicate detection problem which involvesfinding a consistent cut of a distributed computation,if it exists, that satisfies the given global predicate.Detecting a predicate in a computation is, however, anNP-complete problem. To ameliorate the associated combinatorialexplosion problem, we introduce the notion of computationslice in our earlier papers [5, 10]. Intuitively, sliceis a concise representation of those consistent cuts that satisfya certain condition. To detect a predicate, rather thansearching the state-space of the computation, it is muchmore efficient to search the state-space of the slice. Inthis paper, we provide efficient algorithms to compute theslice for several classes of predicates. Our experimentalresults demonstrate that slicing can lead to an exponentialimprovement over existing techniques in terms of time andspace.
A High-Level Simulator for the Primitive Classifier Chip of the Raycasting Machine
Authors: Subrata Dasgupta
Venue:  (1989)

Raycasting is a process in which an array of rays, all parallel to each other, are allowed to intersect with object(s). Ray-object intersections are next calculated and the information used to compute a variety of information about the object(s). As an example, we can detect whether two objects are actually intersection or are separate when a frontal view shows their boundaries overlapped. Although raycasting is often computationally intensive, it is more valuable than simple surface calculation techniques like the Pixel Planes machine in applications that require volume information of objects, for example: calculating the moment of inertia of object(s), finding the mass distribution of alloyed or composite object(s), and programming numerically controlled machines. Areas which benefit from raycasting include computer vision, CAD/CAM, robotics, computer graphics and other areas. The Raycasting machine (RCM) is a special-purpose computer capable of classifying a very large number of parallel rays on the basis of whether they do or do not intersect with certain {\em primitive objects}. The architecture is based on Constructive solid geometric (CSG) modeling of objects. CSG is a popular 3D solid modeling methodology and is described in [2],[3],[4]. The underlying idea of the RCM is to model a complex object in terms of a few primitive objects, and then find the intersection of these primitive objects with parallel rays. Finally, when the intersections are computed, the information is combined using the CSG set operators Union, Intersection and Difference. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
Complete PC Upgrade and Maintenance Guide (2003 Edition), 13 edition
Authors: Mark Minasi
Venue:  (2002)

:The Complete PC Upgrade & Maintenance Guide, 2003 Edition, is a problem-solving wonder. In simple, easy-to-follow language, it shows you how to prevent disasters, fix the ones that occur, and maximize your PC's power and longevity. Based on author Mark Minasi's popular $800 seminars, this book is an unbelievable value. For only $59.99 U.S., it teaches you everything you need to know to meet all your PC challenges.
Cultivating the Agent Economy
Authors: James E. Hanson
Venue: Proceedings of the Fifth International Symposium on Autonomous Decentralized Systems (2001)

Advances in eletronic commerce and agent technology are pushing the world rapidly toward ever-increasing e-business automation. The logical development of this movement is agent-based electronic commerce, in which software agents act as autonomous (or semi-autonomous) businesses in their own right, buying and selling information goods and services online. We review some of the forseeable developments and challenges in the growth of agent-based electronic commerce.
iWeaver: towards 'learning style'-based e-learning in computer science education
Authors: Christian Wolf
Venue: Proceedings of the fifth Australasian conference on Computing education - Volume 20 (2003)

Although learning style theory is widely accepted amongst educational theorists in the context of traditional classroom environments, there is still little research on the adaptation to individual styles in an e-learning environment. In particular the possibility of fluctuations in a learning style with changing tasks or content has not yet been addressed. The described PhD project named iWeaver was designed to provide a flexible, yet manageable environment for the learner by implementing adaptive hypermedia techniques. iWeaver draws upon the widely recognised Dunn & Dunn learning styles model and derived learning strategies. It uses database-driven JavaServer Pages, which generate 'media experiences' (e.g. interactive Flash animations or streaming audio) and other specifically developed 'learning tools' to teach the Java programming language. This paper describes the system architecture of iWeaver and gives technical details on the implementation of specific media experiences and learning tools. An approach to predict and accommodate fluctuations in a learning style profile that will be integrated in a future version of the environment is discussed.
An effective parallelization of execution of multijoins in multiprocessor systems
Venue: Proceedings of the 1996 International Symposium on Parallel Architectures, Algorithms and Networks (1996)

In this paper, we study a synchronous execution strategy for parallel join computation in multiprocessor systems. Through a further comprehensive investigation of the processor allocation problem and inter-operator parallelization problem, we present a new algorithm for producing an effective parallelization plan for processing multijoins. Besides theoretical analysis, the efficiency and effectiveness of our new algorithm are supported by our experiments.