Now showing items 589-608 of 1066

  • Multiscale Image Segmentation using Wavelet-domain Hidden Markov Models 

    Choi, Hyeokho; Baraniuk, Richard G. (2001-09-01)
    We introduce a new image texture segmentation algorithm, HMTseg, based on wavelets and the hidden Markov tree (HMT) model. The HMT is a tree-structured probabilistic graph that captures the statistical properties of the ...
  • Multiscale Likelihood Analysis and Complexity Penalized Estimation 

    Kolaczyk, Eric D.; Nowak, Robert David (2001-08-20)
    We describe here a framework for a certain class of multiscale likelihood factorization wherein, in analogy to a wavlet decomposition of an L² function, a given likelihood function has an alternative representation as a ...
  • Multiscale Likelihood Analysis and Image Reconstruction 

    Willett, Rebecca; Nowak, Robert David (2003-08-20)
    The nonparametric multiscale polynomial and platelet methods presented here are powerful new tools for signal and image denoising and reconstruction. Unlike traditional wavelet-based multiscale methods, these methods are ...
  • Multiscale Manifold Representation and Modeling 

    Choi, Hyeokho; Baraniuk, Richard G. (2005-03-01)
    Many real world data sets can be viewed as points in a higher-dimensional space that lie concentrated around a lower-dimensional manifold structure. We propose a new multiscale representation for such point clouds based ...
  • Multiscale modeling and estimation of Poisson processes with application to photon-limited imaging 

    Timmerman, Klaus; Nowak, Robert David (1999-04-20)
    Many important problems in engineering and science are well-modeled by Poisson processes. In many applications it is of great interest to accurately estimate the intensities underlying observed Poisson data. In particular, ...
  • Multiscale Nature of Network Traffic 

    Abry, Patrice; Baraniuk, Richard G.; Flandrin, Patrick; Riedi, Rudolf H.; Veitch, Darryl (2002-05-01)
    The complexity and richness of telecommunications traffic is such that one may despair to find any regularity or explanatory principles. Nonetheless, the discovery of scaling behavior in tele-traffic has provided hope that ...
  • Multiscale Queuing Analysis 

    Ribeiro, Vinay Joseph; Riedi, Rudolf H.; Baraniuk, Richard G. (2006-10-01)
    This paper introduces a new multiscale framework for estimating the tail probability of a queue fed by an arbitrary traffic process. Using traffic statistics at a small number of time scales, our analysis extends the ...
  • Multiscale Queuing Analysis 

    Ribeiro, Vinay Joseph; Riedi, Rudolf H.; Baraniuk, Richard G. (2004-09-01)
    We develop a new approach to queuing analysis for an infinite-length queue with constant service rate fed by an arbitrary traffic process. Our approach is particularly relevant to queues fed with long-range-dependent (LRD) ...
  • Multiscale Queuing Analysis of Long-Range-Dependent Network Traffic 

    Ribeiro, Vinay Joseph; Riedi, Rudolf H.; Crouse, Matthew; Baraniuk, Richard G. (2001-02-20)
    This paper develops a novel approach to queuing analysis tailor-made for multiscale long-range-dependent (LRD) traffic models. We review two such traffic models, the wavelet-domain independent Gaussian model (WIG) and the ...
  • Multiscale Queuing Analysis of Long-Range-Dependent Network Traffic 

    Ribeiro, Vinay Joseph; Riedi, Rudolf H.; Crouse, Matthew; Baraniuk, Richard G. (2000-03-01)
    Many studies have indicated the importance of capturing scaling properties when modeling traffic loads; however, the influence of long-range dependence (LRD) and marginal statistics still remains on unsure footing. In this ...
  • Multiscale SAR Image Segmentation using Wavelet-domain Hidden Markov Tree Models 

    Venkatachalam, Vidya; Choi, Hyeokho; Baraniuk, Richard G. (2000-04-01)
    We study the segmentation of SAR imagery using wavelet-domain Hidden Markov Tree (HMT) models. The HMT model is a tree-structured probabilistic graph that captures the statistical properties of the wavelet transforms of ...
  • The Multiscale Structure of Non-Differentiable Image Manifolds 

    Wakin, Michael; Donoho, David; Choi, Hyeokho; Baraniuk, Richard G. (2005-08-01)
    In this paper, we study families of images generated by varying a parameter that controls the appearance of the object/scene in each image. Each image is viewed as a point in high-dimensional space; the family of images ...
  • Multiscale Texture Segmentation of Dip-cube Slices using Wavelet-domain Hidden Markov Trees 

    Magrin-Chagnolleau, Ivan; Choi, Hyeokho; van Spaendonck, Rutger; Steeghs, Philippe; Baraniuk, Richard G. (1999-11-01)
    Wavelet-domain Hidden Markov Models (HMMs) are powerful tools for modeling the statistical properties of wavelet coefficients. By characterizing the joint statistics of wavelet coefficients, HMMs efficiently capture the ...
  • Multiscale Texture Segmentation using Wavelet-domain Hidden Markov Models 

    Choi, Hyeokho; Baraniuk, Richard G. (1998-11-01)
    Wavelet-domain hidden Markov tree (HMT) models are powerful tools for modeling the statistical properties of wavelet transforms. By characterizing the joint statistics of the wavelet coefficients, HMTs efficiently capture ...
  • Multiscale Wedgelet Image Analysis: Fast Decompositions and Modeling 

    Romberg, Justin; Wakin, Michael; Baraniuk, Richard G. (2002-06-01)
    The most perceptually important features in images are geometrical, the most prevalent being the smooth contours ("edges") that separate different homogeneous regions and delineate distinct objects. Although wavelet based ...
  • Multitier Wireless Communications 

    Aazhang, Behnaam; Cavallaro, Joseph R. (2001-06-20)
    Next-generation computing systems will be highly integrated using wireless networking. The Rice Everywhere NEtwork (RENE) project is exploring the integration of WCDMA cellular systems, high speed wireless LANs, and home ...
  • Multitier Wireless Systems 

    Aazhang, Behnaam; Cavallaro, Joseph R. (2000-05-01)
    Next-generation computing systems will be highly integrated using wireless networking. The Rice Everywhere NEtwork (RENE) project is exploring the integration of WCDMA cellular systems, high speed wireless LANs, and home ...
  • Multiuser Channel Estimation and Tracking for Long Code CDMA Systems 

    Bhashyam, Srikrishna; Aazhang, Behnaam (2002-01-15)
    Channel estimation techniques for code-division multiple access (CDMA) systems need to combat multiple access interference (MAI) effectively. Most existing estimation techniques are designed for CDMA systems with short ...
  • Multiuser Channel Estimation for Long Code CDMA Systems 

    Bhashyam, Srikrishna; Aazhang, Behnaam (2000-09-20)
    Channel estimation techniques for code-division multiple access (CDMA) systems need to combat multiple access interference (MAI) effectively. Most existing estimation techniques are designed for CDMA systems with short ...
  • Multiuser detection in fast-fading multipath environments 

    Sayeed, Akbar M.; Sendonaris, Andrew; Aazhang, Behnaam (1998-12-20)
    We propose a new framework for multiuser detection in fast-fading channels that are encountered in many mobile communication scenarios. Existing multiuser RAKE receivers, developed to combat multipath fading and multiuser ...