Browsing MIT Open Access Articles by Title
Now showing items 2966729686 of 34872

Sparse optimization for robust and efficient loop closing
(Elsevier BV, 201704)It is essential for a robot to be able to detect revisits or loop closures for longterm visual navigation. A key insight explored in this work is that the loopclosing event inherently occurs sparsely, i.e., the image ... 
Sparse Projections of Medical Images onto Manifolds
(SpringerVerlag Berlin Heidelberg, 2013)Manifold learning has been successfully applied to a variety of medical imaging problems. Its use in realtime applications requires fast projection onto the lowdimensional space. To this end, outofsample extensions are ... 
Sparse Quantum Codes from Quantum Circuits
(Association for Computing Machinery (ACM), 201506)Sparse quantum codes are analogous to LDPC codes in that their check operators require examining only a constant number of qubits. In contrast to LDPC codes, good sparse quantum codes are not known, and even to encode a ... 
Sparse Recovery for Earth Mover Distance
(University of Ilinois at UrbanaChampaign, 201009)We initiate the study of sparse recovery problems under the EarthMover Distance (EMD). Specically, we design a distribution over m x n matrices A, for m << n, such that for any x, given Ax, we can recover a ksparse ... 
Sparse Recovery Using Sparse Matrices
(Institute of Electrical and Electronics Engineers, 201006)In this paper, we survey algorithms for sparse recovery problems that are based on sparse random matrices. Such matrices has several attractive properties: they support algorithms with low computational complexity, and ... 
Sparse recovery with partial support knowledge
(Springer Berlin / Heidelberg, 201108)The goal of sparse recovery is to recover the (approximately) best ksparse approximation [ˆ over x] of an ndimensional vector x from linear measurements Ax of x. We consider a variant of the problem which takes into ... 
Sparse Sensing and DMDBased Identification of Flow Regimes and Bifurcations in Complex Flows
(Society for Industrial and Applied Mathematics, 201706)We present a sparse sensing framework based on dynamic mode decomposition (DMD) to identify flow regimes and bifurcations in largescale thermofluid systems. Motivated by realtime sensing and control of thermalfluid flows ... 
Sparse sensing for resourceconstrained depth reconstruction
(Institute of Electrical and Electronics Engineers (IEEE), 201612)We address the following question: is it possible to reconstruct the geometry of an unknown environment using sparse and incomplete depth measurements? This problem is relevant for a resourceconstrained robot that has to ... 
Sparse signconsistent Johnson–Lindenstrauss matrices: Compression with neurosciencebased constraints
(National Academy of Sciences (U.S.), 201411)Johnson–Lindenstrauss (JL) matrices implemented by sparse random synaptic connections are thought to be a prime candidate for how convergent pathways in the brain compress information. However, to date, there is no complete ... 
Sparse signal recovery and acquisition with graphical models
(Institute of Electrical and Electronics Engineers (IEEE), 201011)A great deal of theoretic and algorithmic research has revolved around sparsity view of signals over the last decade to characterize new, subNyquist sampling limits as well as tractable algorithms for signal recovery from ... 
Sparse spectral estimation from point process observations
(Institute of Electrical and Electronics Engineers (IEEE), 201706)We consider the problem of estimating the power spectral density of the neural covariates underlying the spiking of a neuronal population. We assume the spiking of the neuronal ensemble to be described by Bernoulli statistics. ... 
Sparse sums of squares on finite abelian groups and improved semidefinite lifts
(Springer Berlin Heidelberg, 201601)Let G be a finite abelian group. This paper is concerned with nonnegative functions on G that are sparse with respect to the Fourier basis. We establish combinatorial conditions on subsets S and T of Fourier basis elements ... 
Sparsification of RNA structure prediction including pseudoknots
(BioMed Central Ltd, 201012)Abstract Background Although many RNA molecules contain pseudoknots, computational prediction of pseudoknotted RNA structure is still in its infancy due to high running time and space consumption implied by the dynamic ... 
A Sparsity Detection Framework for On–Off Random Access Channels
(Society of Photooptical Instrumentation Engineers, 200909)This paper considers a simple onoff random multiple access channel, where n users communicate simultaneously to a single receiver over m degrees of freedom. Each user transmits with probability lambda, where typically ... 
Sparsity Maximization under a Quadratic Constraint with Applications in Filter Design
(Institute of Electrical and Electronics Engineers, 201006)This paper considers two problems in sparse filter design, the first involving a leastsquares constraint on the frequency response, and the second a constraint on signaltonoise ratio relevant to signal detection. It is ... 
SparsityDriven Synthetic Aperture Radar Imaging: Reconstruction, autofocusing, moving targets, and compressed sensing
(Institute of Electrical and Electronics Engineers (IEEE), 201406)This article presents a survey of recent research on sparsitydriven synthetic aperture radar (SAR) imaging. In particular, it reviews 1) the analysis and synthesisbased sparse signal representation formulations for SAR ... 
SparsityPromoting Calibration for GRAPPA Accelerated Parallel MRI Reconstruction
(Institute of Electrical and Electronics Engineers (IEEE), 201306)The amount of calibration data needed to produce images of adequate quality can prevent autocalibrating parallel imaging reconstruction methods like generalized autocalibrating partially parallel acquisitions (GRAPPA) ... 
SPASM and Twitch Domains in SAdenosylmethionine (SAM) Radical Enzymes
(American Society for Biochemistry and Molecular Biology (ASBMB), 201412)SAdenosylmethionine (SAM, also known as AdoMet) radical enzymes use SAM and a [4Fe4S] cluster to catalyze a diverse array of reactions. They adopt a partial triosephosphate isomerase (TIM) barrel fold with N and ... 
Spatial and temporal colonization dynamics of segmented filamentous bacteria is influenced by gender, age and experimental infection with Helicobacter hepaticus in Swiss Webster mice
(Elsevier, 201410)In this study, we examined colonization dynamics of segmented filamentous bacteria (SFB) in intestine of Swiss Webster (SW) mice infected with Helicobacter hepaticus (Hh). At 8 weeks postinoculation with Hh (WPI), cecal ... 
Spatial and Temporal Patterns in LargeScale Traffic Speed Prediction
(Institute of Electrical and Electronics Engineers (IEEE), 201404)The ability to accurately predict traffic speed in a large and heterogeneous road network has many useful applications, such as route guidance and congestion avoidance. In principle, datadriven methods, such as support ...