Read by QxMD icon Read

Compressed sensing

Jiedi Sun, Yang Yu, Jiangtao Wen
Remote monitoring of bearing conditions, using wireless sensor network (WSN), is a developing trend in the industrial field. In complicated industrial environments, WSN face three main constraints: low energy, less memory, and low operational capability. Conventional data-compression methods, which concentrate on data compression only, cannot overcome these limitations. Aiming at these problems, this paper proposed a compressed data acquisition and reconstruction scheme based on Compressed Sensing (CS) which is a novel signal-processing technique and applied it for bearing conditions monitoring via WSN...
June 21, 2017: Sensors
Lingxiao Lv, Panpan Zhang, Tong Xu, Liangti Qu
Approaching to the super-sensitivity, we herein develop a pressure sensor based on fully bubbled ultralight graphene block through a simple sparkling strategy. The obtained sparking graphene block (SGB) exhibits excellent elasticity even at 95% compressive strain and rebounds a steel ball with an ultra-fast recovery speed (~1085 mm s-1). Particularly, the SGB based sensor reveals a record pressure sensitivity of 229.8 kPa-1, much higher than other graphene materials due to the highly cavity-branched internal structure...
June 20, 2017: ACS Applied Materials & Interfaces
Renyuan Zhang, Siyang Cao
In this paper, a new millimeter wave 3D imaging radar is proposed. The user just needs to move the radar along a circular track, and high resolution 3D imaging can be generated. The proposed radar uses the movement of itself to synthesize a large aperture in both the azimuth and elevation directions. It can utilize inverse Radon transform to resolve 3D imaging. To improve the sensing result, the compressed sensing approach is further investigated. The simulation and experimental result further illustrated the design...
June 17, 2017: Sensors
A Reci, A J Sederman, L F Gladden
The mathematics of inverse problems has relevance across numerous estimation problems in science and engineering. L1 regularization has attracted recent attention in reconstructing the system properties in the case of sparse inverse problems; i.e., when the true property sought is not adequately described by a continuous distribution, in particular in Compressed Sensing image reconstruction. In this work, we focus on the application of L1 regularization to a class of inverse problems; relaxation-relaxation, T1-T2, and diffusion-relaxation, D-T2, correlation experiments in NMR, which have found widespread applications in a number of areas including probing surface interactions in catalysis and characterizing fluid composition and pore structures in rocks...
May 25, 2017: Journal of Magnetic Resonance
Benjamin Kaltenbach, Andreas M Bucher, Julian L Wichmann, Dominik Nickel, Christoph Polkowski, Renate Hammerstingl, Thomas J Vogl, Boris Bodelle
OBJECTIVES: The aim of this study was to assess the feasibility of a free-breathing dynamic liver imaging technique using a prototype Cartesian T1-weighted volumetric interpolated breathhold examination (VIBE) sequence with compressed sensing and simultaneous acquisition of a navigation signal for hard-gated and motion state-resolved reconstruction. MATERIALS AND METHODS: A total of 43 consecutive oncologic patients (mean age, 66 ± 11 years; 44% female) underwent free-breathing dynamic liver imaging for the evaluation of liver metastases from colorectal cancer using a prototype Cartesian VIBE sequence (field of view, 380 × 345 mm; image matrix, 320 × 218; echo time/repetition time, 1...
June 16, 2017: Investigative Radiology
Antoine Richard, Efren Fernandez-Grande, Jonas Brunskog, Cheol-Ho Jeong
A method is proposed to estimate the surface impedance of a large absorptive panel from free-field measurements with a spherical microphone array. The method relies on the reconstruction of the pressure and the particle velocity on the studied surface using an equivalent source method based on spherical array measurements. The sound field measured by the array is mainly composed of an incident and a reflected wave, so it can be represented as a spatially sparse problem. This makes it possible to use compressive sensing in order to enhance the resolution and the quality of the estimation...
June 2017: Journal of the Acoustical Society of America
Ming-Jie Sun, Ling-Tong Meng, Matthew P Edgar, Miles J Padgett, Neal Radwell
Single-pixel imaging is an alternate imaging technique particularly well-suited to imaging modalities such as hyper-spectral imaging, depth mapping, 3D profiling. However, the single-pixel technique requires sequential measurements resulting in a trade-off between spatial resolution and acquisition time, limiting real-time video applications to relatively low resolutions. Compressed sensing techniques can be used to improve this trade-off. However, in this low resolution regime, conventional compressed sensing techniques have limited impact due to lack of sparsity in the datasets...
June 14, 2017: Scientific Reports
Marina Haikin, Ram Zamir, Matan Gavish
We draw a random subset of [Formula: see text] rows from a frame with [Formula: see text] rows (vectors) and [Formula: see text] columns (dimensions), where [Formula: see text] and [Formula: see text] are proportional to [Formula: see text] For a variety of important deterministic equiangular tight frames (ETFs) and tight non-ETFs, we consider the distribution of singular values of the [Formula: see text]-subset matrix. We observe that, for large [Formula: see text], they can be precisely described by a known probability distribution-Wachter's MANOVA (multivariate ANOVA) spectral distribution, a phenomenon that was previously known only for two types of random frames...
June 13, 2017: Proceedings of the National Academy of Sciences of the United States of America
Yang Xu, Barbara C Malt, Mahesh Srinivasan
One way that languages are able to communicate a potentially infinite set of ideas through a finite lexicon is by compressing emerging meanings into words, such that over time, individual words come to express multiple, related senses of meaning. We propose that overarching communicative and cognitive pressures have created systematic directionality in how new metaphorical senses have developed from existing word senses over the history of English. Given a large set of pairs of semantic domains, we used computational models to test which domains have been more commonly the starting points (source domains) and which the ending points (target domains) of metaphorical mappings over the past millennium...
June 8, 2017: Cognitive Psychology
Mingsian R Bai, You Siang Chen, Yi-Yang Lo
A farfield random array is implemented for noise source identification. Microphone positions are optimized, with the aid of the simulated annealing method. A two-stage localization and separation algorithm is devised on the basis of the equivalent source method (ESM). In the localization stage, the active source regions are located by using the delay-and-sum method, followed by a parametric localization procedure, stochastic maximum likelihood algorithm. Multidimensional nonlinear optimization is exploited in the bearing estimation process...
May 2017: Journal of the Acoustical Society of America
Fabrice Katzberg, Radoslaw Mazur, Marco Maass, Philipp Koch, Alfred Mertins
Closed-room scenarios are characterized by reverberation, which decreases the performance of applications such as hands-free teleconferencing and multichannel sound reproduction. However, exact knowledge of the sound field inside a volume of interest enables the compensation of room effects and allows for a performance improvement within a wide range of applications. The sampling of sound fields involves the measurement of spatially dependent room impulse responses, where the Nyquist-Shannon sampling theorem applies in the temporal and spatial domains...
May 2017: Journal of the Acoustical Society of America
Yansong Zhu, Abhinav K Jha, Jakob K Dreyer, Hanh N D Le, Jin U Kang, Per E Roland, Dean F Wong, Arman Rahmim
Fluorescence molecular tomography (FMT) is a promising tool for real time in vivo quantification of neurotransmission (NT) as we pursue in our BRAIN initiative effort. However, the acquired image data are noisy and the reconstruction problem is ill-posed. Further, while spatial sparsity of the NT effects could be exploited, traditional compressive-sensing methods cannot be directly applied as the system matrix in FMT is highly coherent. To overcome these issues, we propose and assess a three-step reconstruction method...
January 28, 2017: Proceedings of SPIE
Jakob Weiss, Mike Notohamiprodjo, Petros Martirosian, Jana Taron, Marcel D Nickel, Manuel Kolb, Fabian Bamberg, Konstantin Nikolaou, Ahmed E Othman
PURPOSE: To evaluate the feasibility of a self-gated free-breathing volume-interpolated breath-hold examination (VIBE) sequence using compressed sensing (CS) for contrast-enhanced multiphase liver MRI. MATERIALS AND METHODS: We identified 23 patients who underwent multiphase gadobutrol-enhanced liver magnetic resonance imaging (MRI) using 1) a prototype free-breathing VIBE sequence with respiratory self-gating and CS (VIBECS ), and 2) a standard breath-hold VIBE (VIBESTD ) on the same 1...
June 8, 2017: Journal of Magnetic Resonance Imaging: JMRI
Ajin Joy, Joseph Suresh Paul
PURPOSE: Eliminate the need for parametric tuning in total variation (TV) based multichannel compressed-sensing image reconstruction using statistically optimized nonlinear diffusion without compromising image quality. THEORY AND METHODS: Nonlinear diffusion controls the denoising process using a contrast parameter that separates the gradients corresponding to noise and true edges in the image. This parameter is statistically estimated from the variance of combined image gradient to yield minimum steady-state reconstruction error...
June 7, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Ping Xu, Junfeng Liu, Lingyun Xue, Jingcheng Zhang, Bo Qiu
With the development of hyperspectral technology, to establish an effective spectral data compressive reconstruction method that can improve data storage, transmission, and maintaining spectral information is critical for quantitative remote sensing research and application in vegetation. The spectral adaptive grouping distributed compressive sensing (AGDCS) algorithm is proposed, which enables a distributed compressed sensing reconstruction of plant hyperspectral data. The spectral characteristics of hyperspectral data are analyzed and the joint sparse model is constructed...
June 7, 2017: Sensors
H K Svensson, L -E Olsson, T Hansson, J Karlsson, E Hansson-Olofsson
Vertebral compression fracture (VCF) is a common fragility fracture and the starting point of a lasting, painful, disabling condition. The aim was to summarize evidence of person-centered/non-medical interventions supporting women with VCF. Results show small numbers of studies with only probable effect on function, pain, QoL, fear of falling, and psychological symptoms. The vertebral compression fracture (VCF) caused by osteoporosis is the third most common fragility fracture worldwide. Previously, it was believed that the pain caused by VCF was self-subsiding within weeks or a few months post-fracture...
June 6, 2017: Osteoporosis International
Michael W Hudoba, Yi Luo, Angelita Zacharias, Michael G Poirier, Carlos E Castro
The ability to self-assemble nanodevices with programmed structural dynamics that can sense and respond to the local environment could enable transformative applications in fields including molecular robotics, nanomanufacturing, and nanomedicine. The responsive function of biomolecules is often driven by alterations in conformational distributions mediated by highly sensitive interactions with the local environment. Here, we mimic this approach by engineering inherent nanoscale structural dynamics (nanodynamics) into a DNA device that exhibits a distribution of conformations including two stable states separated by a transition state where the energy barrier height is on the scale of the thermal energy, kBT = 4...
June 9, 2017: ACS Nano
F Ingremeau, M E Dolega, J Gallagher, I Wang, G Cappello, A Delon
Diffusion and transport of small molecules within hydrogel networks are of high interest for biomedical and pharmaceutical research. Herein, using fluorescence correlation spectroscopy (FCS), we experimentally showed that the diffusion time in the hydrogel was directly related to the mechanical state (compression or swelling) and thus to the volume fraction of the gel. Following this observation, we developed cell-like barometers in the form of PAA microbeads, which when incorporated between cells and combined with a diffusion-based optical readout could serve as the first biosensors to measure the local pressure inside the growing biological tissues...
June 14, 2017: Soft Matter
Qingsong Yang, Wenxiang Cong, Ge Wang
X-ray phase contrast imaging is an important mode due to its sensitivity to subtle features of soft biological tissues. Grating-based differential phase contrast (DPC) imaging is one of the most promising phase imaging techniques because it works with a normal x-ray tube of a large focal spot at a high flux rate. However, a main obstacle before this paradigm shift is the fabrication of large-area gratings of a small period and a high aspect ratio. Imaging large objects with a size-limited grating results in data truncation which is a new type of the interior problem...
August 28, 2016: Proceedings of SPIE
Kyle Van Volkinburg, Gregory Washington
This paper reports on a wearable gesture-based controller fabricated using the sensing capabilities of the flexible thin-film piezoelectric polymer polyvinylidene fluoride (PVDF) which is shown to repeatedly and accurately discern, in real time, between right and left hand gestures. The PVDF is affixed to a compression sleeve worn on the forearm to create a wearable device that is flexible, adaptable, and highly shape conforming. Forearm muscle movements, which drive hand motions, are detected by the PVDF which outputs its voltage signal to a developed microcontroller-based board and processed by an artificial neural network that was trained to recognize the generated voltage profile of right and left hand gestures...
May 29, 2017: IEEE Transactions on Biomedical Circuits and Systems
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"