%0 Journal Article
%J IEEE Transactions on Pattern Analysis and Machine Intelligence
%D 2006
%T A 3D shape constraint on video
%A Hui Ji
%A FermÃ¼ller, Cornelia
%K 3D motion estimation
%K algorithms
%K Artificial intelligence
%K CAMERAS
%K decoupling translation from rotation
%K Estimation error
%K Fluid flow measurement
%K Image Enhancement
%K Image Interpretation, Computer-Assisted
%K Image reconstruction
%K Imaging, Three-Dimensional
%K Information Storage and Retrieval
%K integration of motion fields
%K Layout
%K minimisation
%K Minimization methods
%K Motion estimation
%K multiple motion fields
%K parameter estimation
%K Pattern Recognition, Automated
%K Photography
%K practical constrained minimization
%K SHAPE
%K shape and rotation.
%K shape vectors
%K stability
%K structure estimation
%K surface normals
%K Three-dimensional motion estimation
%K video 3D shape constraint
%K Video Recording
%K video signal processing
%X We propose to combine the information from multiple motion fields by enforcing a constraint on the surface normals (3D shape) of the scene in view. The fact that the shape vectors in the different views are related only by rotation can be formulated as a rank = 3 constraint. This constraint is implemented in an algorithm which solves 3D motion and structure estimation as a practical constrained minimization. Experiments demonstrate its usefulness as a tool in structure from motion providing very accurate estimates of 3D motion.
%B IEEE Transactions on Pattern Analysis and Machine Intelligence
%V 28
%P 1018 - 1023
%8 2006/06//
%@ 0162-8828
%G eng
%N 6
%R 10.1109/TPAMI.2006.109
%0 Conference Paper
%B Proceedings of the 2005 conference on Applications, technologies, architectures, and protocols for computer communications
%D 2005
%T Implications of autonomy for the expressiveness of policy routing
%A Feamster, Nick
%A Johari,Ramesh
%A Balakrishnan,Hari
%K autonomy
%K BGP
%K Internet
%K policy
%K protocol
%K Routing
%K Safety
%K stability
%X Thousands of competing autonomous systems must cooperate with each other to provide global Internet connectivity. Each autonomous system (AS) encodes various economic, business, and performance decisions in its routing policy. The current interdomain routing system enables each AS to express policy using rankings that determine how each router inthe AS chooses among different routes to a destination, and filters that determine which routes are hidden from each neighboring AS. Because the Internet is composed of many independent, competing networks, the interdomain routing system should provide autonomy, allowing network operators to set their rankings independently, and to have no constraints on allowed filters. This paper studies routing protocol stability under these conditions. We first demonstrate that certain rankings that are commonly used in practice may not ensure routing stability. We then prove that, when providers can set rankings and filters autonomously, guaranteeing that the routing system will converge to a stable path assignment essentially requires ASes to rank routes based on AS-path lengths. We discuss the implications of these results for the future of interdomain routing.
%B Proceedings of the 2005 conference on Applications, technologies, architectures, and protocols for computer communications
%S SIGCOMM '05
%I ACM
%C New York, NY, USA
%P 25 - 36
%8 2005///
%@ 1-59593-009-4
%G eng
%U http://doi.acm.org/10.1145/1080091.1080096
%R 10.1145/1080091.1080096
%0 Journal Article
%J Signal Processing, IEEE Transactions on
%D 1995
%T On the stability of sequential updates and downdates
%A Stewart, G.W.
%K algorithm;Cholesky
%K algorithm;downdating
%K algorithm;error
%K algorithm;URV
%K algorithms;hyperbolic
%K analysis;matrix
%K analysis;sequential
%K Chambers'
%K condition;rounding
%K decomposition;backward
%K decomposition;numerical
%K decomposition;plane
%K decompositions;LINPACK
%K decompositions;updating
%K downdates;sequential
%K error
%K errors;sequences;
%K orthogonal
%K rotations;relational
%K stability
%K stability;roundoff
%K stable
%K transformations;matrix
%K updates;stability;two-sided
%X The updating and downdating of Cholesky decompositions has important applications in a number of areas. There is essentially one standard updating algorithm, based on plane rotations, which is backward stable. Three downdating algorithms have been treated in the literature: the LINPACK algorithm, the method of hyperbolic transformations, and Chambers' (1971) algorithm. Although none of these algorithms is backward stable, the first and third satisfy a relational stability condition. It is shown that relational stability extends to a sequence of updates and downdates. In consequence, other things being equal, if the final decomposition in the sequence is well conditioned, it will be accurately computed, even though intermediate decompositions may be almost completely inaccurate. These results are also applied to the two-sided orthogonal decompositions, such as the URV decomposition
%B Signal Processing, IEEE Transactions on
%V 43
%P 2642 - 2648
%8 1995/11//
%@ 1053-587X
%G eng
%N 11
%R 10.1109/78.482114
%0 Conference Paper
%B Proceedings of 10th International Conference on Pattern Recognition, 1990
%D 1990
%T Purposive and qualitative active vision
%A Aloimonos, J.
%K active vision
%K Automation
%K brain models
%K complex visual tasks
%K Computer vision
%K environmental knowledge
%K highly sophisticated navigational tasks
%K HUMANS
%K Image reconstruction
%K intentions
%K Kinetic theory
%K Laboratories
%K Medusa
%K Motion analysis
%K Navigation
%K planning
%K planning (artificial intelligence)
%K purposive-qualitative vision
%K recovery problem
%K Robust stability
%K Robustness
%K SHAPE
%K stability
%X The traditional view of the problem of computer vision as a recovery problem is questioned, and the paradigm of purposive-qualitative vision is offered as an alternative. This paradigm considers vision as a general recognition problem (recognition of objects, patterns or situations). To demonstrate the usefulness of the framework, the design of the Medusa of CVL is described. It is noted that this machine can perform complex visual tasks without reconstructing the world. If it is provided with intentions, knowledge of the environment, and planning capabilities, it can perform highly sophisticated navigational tasks. It is explained why the traditional structure from motion problem cannot be solved in some cases and why there is reason to be pessimistic about the optimal performance of a structure from motion module. New directions for future research on this problem in the recovery paradigm, e.g., research on stability or robustness, are suggested
%B Proceedings of 10th International Conference on Pattern Recognition, 1990
%I IEEE
%V i
%P 346-360 vol.1 - 346-360 vol.1
%8 1990/06/16/21
%@ 0-8186-2062-5
%G eng
%R 10.1109/ICPR.1990.118128