Now showing items 40208-40227 of 76154

    • Multiplicity of states in a many-body system 

      Lee, Ching-Tsung (1965)
      In this thesis, a certain theorem in the representation theory of symmetric group is presented in a more detailed and precise form. The possibility of its application to a many-body system is pointed out. Specifically, its application to a system of N electrons has been worked out in some detail. Thus, the formulae for the number of possible states ...
    • Multireference symmetry-projected variational approximation for the ground state of the doped one-dimensional Hubbard model 

      (2014)
      The few determinant (FED) approximation introduced in our previous work [Phys. Rev. B 87, 235129 (2013)] is used to describe the ground state, characterized by well-defined spin and space group symmetry quantum numbers as well as doping fractions Ne/Nsites, of one-dimensional Hubbard lattices with nearest-neighbor hopping and periodic boundary ...
    • Multiresolution Intensity Estimation of Piecewise Linear Poisson Processes 

      Willett, Rebecca (2001-04-20)
      Given observations of a one-dimensional piecewise linear, length-M Poisson intensity function, our goal is to estimate both the partition points and the parameters of each segment. In order to determine where the breaks lie, we develop a maximum penalized likelihood estimator based on information-theoretic complexity penalization. We construct a ...
    • Multiresolution methods for recovering signals and sets from noisy observations 

      Willett, Rebecca M. (2005)
      The nonparametric multiscale partition-based estimators presented in this thesis are powerful tools for signal reconstruction and set estimation from noisy observations. Unlike traditional wavelet-based multiscale methods, the spatially adaptive and computationally efficient methods presented in this thesis are (a) able to achieve near minimax optimal ...
    • Multiresolution Nonparametric Intensity and Density Estimation 

      Willett, Rebecca; Nowak, Robert David (2002-05-20)
      This paper introduces a new multiscale method for nonparametric piecewise polynomial intensity and density estimation of point processes. Fast, piecewise polynomial, maximum penalized likelihood methods for intensity and density estimation are developed. The recursive partitioning scheme underlying these methods is based on multiscale likelihood ...
    • Multisample bionanochip platform 

      Mcdevitt, John; Christodoulidies, Nicolaos; Floriano, Pierre N.; Abram, Tim (2016-02-02)
      A bionanochip cartridge for analysis of multiple samples or analytes is provided herein, and the cartridge is dimensioned to take advantage of existing robotic microtiter plate handling equipment. Fluidics are specially designed to provide a small footprint and to prevent cross contamination.
    • Multiscale analysis for intensity and density estimation 

      Willett, Rebecca M. (2002)
      The nonparametric multiscale polynomial and platelet algorithms presented in this thesis are powerful new tools for signal and image denoising and reconstruction. Unlike traditional wavelet-based multiscale methods, these algorithms are both well suited to processing Poisson and multinomial data and capable of preserving image edges. At the heart of ...
    • Multiscale Analysis for Intensity and Density Estimation 

      Willett, Rebecca (2002-04-20)
      The nonparametric multiscale polynomial and platelet algorithms presented in this thesis are powerful new tools for signal and image denoising and reconstruction. Unlike traditional wavelet-based multiscale methods, these algorithms are both well suited to processing Poisson and multinomial data and capable of preserving image edges. At the heart of ...
    • Multiscale Analysis of Macromolecular Systems 

      Zheng, Wenwei (2013-12-18)
      Molecular dynamics (MD) simulation serves as both a supplement to experiments and a predictive tool by revealing details inaccessible to current state-of-the-art experimental techniques. The relevant dynamics in complex macromolecular systems correspond to timescales longer than what can be sampled using MD with standard computational resources. In ...
    • Multiscale and Multidimensional Thermodynamic Modeling of Block Copolymer Self-assembly in Solution 

      Xi, Shun (2020-03-06)
      The study of block copolymer self-assembly in solution has been an active subject for years. As one of the most versatile molecules in nature, it is a chemical and biological building block for life. Lipids in aqueous solution self-organize to a bilayer structure that effectively compartmentalize cellular spaces for complex biochemical processes. ...
    • Multiscale Approach to the Determination of the Photoactive Yellow Protein Signaling State Ensemble 

      (2014)
      The nature of the optical cycle of photoactive yellow protein (PYP) makes its elucidation challenging for both experiment and theory. The long transition times render conventional simulation methods ineffective, and yet the short signaling-state lifetime makes experimental data difficult to obtain and interpret. Here, through an innovative combination ...
    • Multiscale Approximation of Piecewise Smooth Two-Dimensional Function using Normal Triangulated Meshes 

      Jansen, Maarten; Baraniuk, Richard G.; Lavu, Sridhar (2005-07-01)
      Multiresolution triangulation meshes are widely used in computer graphics for representing three-dimensional(3-d) shapes. We propose to use these tools to represent 2-d piecewise smooth functions such as grayscale images,because triangles have potential to more efficiently approximate the discontinuities between the smooth pieces than other standard ...
    • A Multiscale Bayesian Framework for Linear Inverse Problems and Its Application to Image Restoration 

      Wan, Yi; Nowak, Robert David (2001-01-20)
      In this paper we develop a wavelet-based statistical method for solving linear inverse problems. The Bayesian framework developed here is general enough to treat a wide class of linear inverse problems involving (white or colored) Gaussian observation noise. In this approach, a signal prior is developed by modeling the signal/imgage wavelet ...
    • Multiscale Classification using Complex Wavelets and Hidden Markov Tree Models 

      Romberg, Justin; Choi, Hyeokho; Baraniuk, Richard G.; Kingsbury, Nicholas G. (2000-09-01)
      Multiresolution signal and image models such as the hidden Markov tree (HMT) aim to capture the statistical structure of smooth and singular (textured and edgy) regions. Unfortunately, models based on the orthogonalwavelet transform suffer from shift-variance, making them less accurate and realistic. In this paper, we extend the HMT modeling framework ...
    • Multiscale Connection-Level Analysis of Network Traffic 

      Sarvotham, Shriram; Riedi, Rudolf H.; Baraniuk, Richard G. (2002-11-01)
      Network traffic exhibits drastically different statistics, ranging from nearly Gaussian marginals and long range dependence at very large time scales to highly non-Gaussian marginals and multifractal scaling on small scales. This behavior can be explained by decomposing traffic into two components according to the connection bandwidth: the small ...
    • A Multiscale Data Representation for Distributed Sensor Networks 

      Wagner, Raymond; Sarvotham, Shriram; Baraniuk, Richard G. (2005-03-01)
      Though several wavelet-based compression solutions for wireless sensor network measurements have been proposed, no such technique has yet appreciated the need to couple a wavelet transform tolerant of irregularly sampled data with the data transport protocol governing communications in the network. As power is at a premium in sensor nodes, such a ...
    • A Multiscale Data Representation for Distributed Sensor Networks: Proofs of Basis Characteristics and Error Bounds 

      Sarvotham, Shriram; Wagner, Raymond; Baraniuk, Richard G. (2004-09-01)
      Provides proofs of Parseval tight-frame membership and approximation properties for the basis proposed in "A Multiscale Data Representation for Distributed Sensor Networks" by R. Wagner, S. Sarvotham, and R. Baraniuk (ICASSP 2005).
    • Multiscale Density Estimation 

      Willett, Rebecca; Nowak, Robert David (2003-08-20)
      The nonparametric density estimation method proposed in this paper is computationally fast, capable of detecting density discontinuities and singularities at a very high resolution, spatially adaptive, and offers near minimax convergence rates for broad classes of densities including Besov spaces. At the heart of this new method lie multiscale signal ...
    • Multiscale Edge Grammars for Complex Wavelet Transforms 

      Romberg, Justin; Choi, Hyeokho; Baraniuk, Richard G. (2001-10-01)
      Wavelet domain algorithms have risen to the forefront of image processing. The power of these algorithms is derived from the fact that the wavelet transform restructures the image in a way that makes statistical modeling easier. Since the edge singularities in an image account for the most important information, understanding how edges behave in ...
    • Multiscale Geometric Image Processing 

      Romberg, Justin; Wakin, Michael; Baraniuk, Richard G. (2003-07-01)
      Since their introduction a little more than 10 years ago, wavelets have revolutionized image processing. Wavelet based algorithms define the state-of-the-art for applications including image coding (JPEG2000), restoration, and segmentation. Despite their success, wavelets have significant shortcomings in their treatment of edges. Wavelets do not ...