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439
Candid covariancefree incremental principal component analysis
 IEEE Trans. Pattern Analysis and Machine Intelligence
, 2003
"... Abstract—Appearancebased image analysis techniques require fast computation of principal components of highdimensional image vectors. We introduce a fast incremental principal component analysis (IPCA) algorithm, called candid covariancefree IPCA (CCIPCA), used to compute the principal components ..."
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Cited by 81 (9 self)
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Abstract—Appearancebased image analysis techniques require fast computation of principal components of highdimensional image vectors. We introduce a fast incremental principal component analysis (IPCA) algorithm, called candid covariancefree IPCA (CCIPCA), used to compute the principal components of a sequence of samples incrementally without estimating the covariance matrix (so covariancefree). The new method is motivated by the concept of statistical efficiency (the estimate has the smallest variance given the observed data). To do this, it keeps the scale of observations and computes the mean of observations incrementally, which is an efficient estimate for some wellknown distributions (e.g., Gaussian), although the highest possible efficiency is not guaranteed in our case because of unknown sample distribution. The method is for realtime applications and, thus, it does not allow iterations. It converges very fast for highdimensional image vectors. Some links between IPCA and the development of the cerebral cortex are also discussed. Index Terms—Principal component analysis, incremental principal component analysis, stochastic gradient ascent (SGA), generalized hebbian algorithm (GHA), orthogonal complement. æ 1
Architectures and Algorithms for FieldProgrammable Gate Arrays with Embedded Memory
, 1997
"... Recent dramatic improvements in integrated circuit fabrication technology have led to FieldProgrammable Gate Arrays (FPGAs) capable of implementing entire digital systems, as opposed to the smaller logic circuits that have traditionally been targeted to FPGAs. Unlike the smaller circuits, these la ..."
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Cited by 60 (5 self)
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Recent dramatic improvements in integrated circuit fabrication technology have led to FieldProgrammable Gate Arrays (FPGAs) capable of implementing entire digital systems, as opposed to the smaller logic circuits that have traditionally been targeted to FPGAs. Unlike the smaller circuits, these large systems often contain memory. Architectural support for the efficient implementation of memory in nextgeneration FPGAs is therefore crucial. This dissertation examines the architecture of FPGAs with memory,aswell as algorithms that map circuits into these devices. Three aspects are considered: the analysis of circuits that contain memory as well as the automated random generation of such circuits, the architecture and algorithms for standalone con#gurable memory devices, and architect...
Routing Using Potentials: A Dynamic Trafficaware Routing Algorithm
 In Proceedings of the 2003 Conference on Applications, Technologies, Architectures, and Protocols for Computer Communications; SIGCOMM ’03; ACM
, 2003
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Image Indexing Using Moments and Wavelets
 IEEE Transactions on Consumer Electronics
, 1996
"... Histogram comparison is a popular technique for image and video indexing. The complexity of the technique can be reduced by representing the histogram by its moments. In this paper, we propose two techniques to improve the performance of basic histogram/momentbased technique. First, we propose to u ..."
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Cited by 51 (4 self)
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Histogram comparison is a popular technique for image and video indexing. The complexity of the technique can be reduced by representing the histogram by its moments. In this paper, we propose two techniques to improve the performance of basic histogram/momentbased technique. First, we propose to use orthogonal Legendre moments for representing histograms. Since Legendre moments are orthogonal, they provide superior indexing performance compared to regular moments at a similar complexity. Secondly, we propose to compare the histograms of wavelet coefficients at different scales. The wavelet coefficients provide important directional information, and hence improve the performance of the basic histogrambased technique. The proposed scheme can be easily extended to color images and also be integrated into a waveletbased image coder. I. INTRODUCTION Digital image/video indexing techniques are becoming increasingly important with the advent of broadband networks (ISDN, ATM) and image/v...
WaveFront Curvature as a Cause of Slow Conduction and Block in Isolated Cardiac Muscle
 Circulation Research
, 1994
"... Abstract We have investigated the role of wavefront curvature on propagation by following the wave front that was diffracted through a narrow isthmus created in a twodimensional ionic model (LuoRudy) of ventricular muscle and in a thin (0.5mm) sheet of sheep ventricular epicardial muscle. The ..."
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Cited by 44 (1 self)
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Abstract We have investigated the role of wavefront curvature on propagation by following the wave front that was diffracted through a narrow isthmus created in a twodimensional ionic model (LuoRudy) of ventricular muscle and in a thin (0.5mm) sheet of sheep ventricular epicardial muscle. The electrical activity in the experimental preparations was imaged by using a highresolution video camera that monitored the changes in fluorescence of the potentiometric dye di4ANEPPS on the surface of the tissue. Isthmuses were created both parallel and perpendicular to the fiber orientation. In both numerical and biological experiments, when a planar wave front reached the isthmus, it was diffracted to an elliptical wave front whose pronounced curvature was very similar to that of a wave front initiated by point stimulation. In addition, the velocity of propagation was reduced in relation to
Missing point estimation in models described by proper orthogonal decomposition
, 2007
"... This paper presents a new method of Missing Point Estimation (MPE) to derive efficient reducedorder models for largescale parametervarying systems. Such systems often result from the discretization of nonlinear partial differential equations. A projectionbased model reduction framework is used w ..."
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Cited by 42 (7 self)
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This paper presents a new method of Missing Point Estimation (MPE) to derive efficient reducedorder models for largescale parametervarying systems. Such systems often result from the discretization of nonlinear partial differential equations. A projectionbased model reduction framework is used where projection spaces are inferred from proper orthogonal decompositions of datadependent correlation operators. The key contribution of the MPE method is to perform online computations efficiently by computing Galerkin projections over a restricted subset of the spatial domain. Quantitative criteria for optimally selecting such a spatial subset are proposed and the resulting optimization problem is solved using an efficient heuristic method. The effectiveness of the MPE method is demonstrated by applying it to a nonlinear computational fluid dynamic model of an industrial glass furnace. For this example, the Galerkin projection can be computed using only 25 % of the spatial grid points without compromising the accuracy of the reduced model.
Optimal Strategies for Free Flight Air Traffic Conflict Resolution
 Journal of Guidance, Control, and Dynamics
, 1997
"... Recent advances in navigation and data communication technologies make it feasible for individual aircraft to plan and fly their trajectories in the presence of other aircraft in the airspace. This way, individual aircraft can take advantage of the atmospheric and traffic conditions to optimally pla ..."
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Cited by 38 (0 self)
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Recent advances in navigation and data communication technologies make it feasible for individual aircraft to plan and fly their trajectories in the presence of other aircraft in the airspace. This way, individual aircraft can take advantage of the atmospheric and traffic conditions to optimally plan their paths. This capability is termed as the free flight concept. While the free flight concept provides new degrees of freedom to the aircraft operators, it also bringsin complexities not present in the current air traffic control system. In the free flight concept, each aircraft has the responsibility for navigating around other aircraft in the airspace. While this is not a difficult task under low speed, low traffic density conditions, the complexities of dealing with potential conflict with multiple aircraft can significantly increase the pilot's work load.
On Reliable Broadcast in a Radio Network
 PODC'05
, 2005
"... We consider the problem of reliable broadcast in an infinite grid (or finite toroidal) radio network under Byzantine and crashstop failures. We present bounds on the maximum number of failures that may occur in any given neighborhood without rendering reliable broadcast impossible. We improve on pr ..."
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Cited by 37 (9 self)
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We consider the problem of reliable broadcast in an infinite grid (or finite toroidal) radio network under Byzantine and crashstop failures. We present bounds on the maximum number of failures that may occur in any given neighborhood without rendering reliable broadcast impossible. We improve on previously proved bounds for the number of tolerable Byzantine faults [6]. Our results indicate that it is possible to achieve reliable broadcast if slightly less than onefourth fraction of nodes in any neighborhood are faulty, and impossible otherwise. We also show that reliable broadcast is achievable with crashstop failures if slightly less than half the nodes in any given neighborhood may be faulty. In particular, we establish exact thresholds under a specific distance metric.
Analysing superimposed oriented patterns
 Image Analysis and Interpretation, 6th IEEE Southwest Symposium on Volume, Pages
, 2004
"... journal = {IEEE Transactions on Image Processing}, publisher = {IEEE}, volume = {15}, number = {12}, year = {2006}, pages = {36903700}} © 2006 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for cre ..."
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Cited by 36 (8 self)
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journal = {IEEE Transactions on Image Processing}, publisher = {IEEE}, volume = {15}, number = {12}, year = {2006}, pages = {36903700}} © 2006 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.
Constrained Motion Control Using Vector Potential Fields
, 2000
"... This paper discusses the generation of a control signal that would instruct the actuators of a robotics manipulator to drive motion along a safe and wellbehaved path to a desired target. The proposed concept of navigation control along with the tools necessary for its construction achieve this goal ..."
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Cited by 30 (9 self)
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This paper discusses the generation of a control signal that would instruct the actuators of a robotics manipulator to drive motion along a safe and wellbehaved path to a desired target. The proposed concept of navigation control along with the tools necessary for its construction achieve this goal. The most significant tool is the artificial vector potential field which shows a better ability to steer motion than does a scalar potential field. The synthesis procedure emphasizes flexibility so that the effort needed to modify the control is commensurate with the change in the geometry of the workspace. Theoretical development along with simulation results are provided.