Results 21 to 30 of about 71,204 (254)

Determination of signal-to-noise ratios and spectral SNRs in cryo-EM low-dose imaging of molecules [PDF]

Journal of Structural Biology, 2009
Attempts to develop efficient classification approaches to the problem of heterogeneity in single-particle reconstruction of macromolecules require phantom data with realistic noise models. We have estimated the signal-to-noise ratios and spectral signal-to-noise ratios for three steps in the electron microscopic image formation from data obtained ...
William T, Baxter, Robert A, Grassucci, Haixiao, Gao, Joachim, Frank   +3 more
openaire   +2 more sources

SNR Wall Effect Alleviation by Generalized Detector Employed in Cognitive Radio Networks

Sensors, 2015
The most commonly used spectrum sensing techniques in cognitive radio (CR) networks, such as the energy detector (ED), matched filter (MF), and others, suffer from the noise uncertainty and signal-to-noise ratio (SNR) wall phenomenon.
Modar Safir Shbat, Vyacheslav Tuzlukov
doaj   +1 more source

Underwater acoustic signal extraction algorithm in a strong noise environment

Journal of Measurement Science and Instrumentation, 2020
In the exploration, tracking and positioning of underwater targets, it is necessary to perform frequency domain analysis and correlation calculation on the underwater acoustic signals of the target radiation.
CHANG Hao, YANG Li-bo, SHI Yu-xuan, HOU Jin-chao   +3 more
doaj  

A new flow chip in combination with multiphoton microscopy as a protocol for longitudinal 3D imaging of tissue calcification under shear stress

FEBS Open Bio, EarlyView.
Miniaturized flow chip platform enabling continuous perfusion and longitudinal multiphoton 3D imaging of vascular smooth muscle cell constructs under physiological flow. Brightfield imaging guides region selection, while CellTracker Green and mRuby‐labeled fetuin‐A visualize cells and mineral deposition, respectively. Magnesium supplementation markedly
Vytautas Kučikas, Aaron D. Morgan, Ignas Čiurlionis, Christian Böhm, Stefan Jockenhövel, Willi Jahnen‐Dechent, Marc A. M. J. van Zandvoort   +6 more
wiley   +1 more source

Improving Photoplethysmograph Signal Quality using Butterworth Filters: Denoising and SNR Evaluation Analysis

Medika Teknika
The photoplethysmography (PPG) signal is a physiological signal vulnerable to noise disorders, especially from environmental movements and interference artifacts.
Roichatun Nashichah, Lusiana, Dinda Trisakti Wahyuningtya   +2 more
doaj   +1 more source

Speech Enhancement Algorithm Based on Auditory Masking Effect [PDF]

Jisuanji gongcheng, 2017
For speech signals in low Signal-to-Noise Ratio(SNR) environment,residual background noise is large when using the traditional spectral subtraction method.Aiming at this problem,this paper puts forward an improved speech enhancement algorithm based on ...
CAI Jun,LI Fei,ZHANG Yi
doaj   +1 more source

Optimizing photoexcitation conditions for time‐resolved X‐ray solution scattering experiments

FEBS Open Bio, EarlyView.
Time‐resolved X‐ray solution scattering (TR‐XSS) is a powerful technique to visualize how proteins change their structure in real time after light activation. Selecting the right laser photoexcitation conditions—fluence, excitation geometry, and sample refresh rate—is critical to maximize the experimental signal while avoiding unwanted side effects ...
Matteo Levantino
wiley   +1 more source

Neurochemical Endpoints to Inform Early‐Stage Trials of Spinocerebellar Ataxia 2 and 3 in a Multisite Setting

Annals of Clinical and Translational Neurology, EarlyView.
ABSTRACT Objective Neurochemical levels measured by brain MR spectroscopy (MRS) have been proposed as endpoints for clinical trials in early‐stage spinocerebellar ataxia (SCA) trials. We tested their trial‐readiness by quantifying neurochemicals in three affected brain regions in early‐stage cohorts of SCA2 and SCA3, examining their reproducibility in ...
James M. Joers, Yaqiao Wei, Dinesh K. Deelchand, Adam Berrington, Young Woo Park, Guita Banan, Michal Povazan, Jens T. Rosenberg, André J. W. van der Kouwe, Tetsuo Ashizawa, Khalaf O. Bushara, Chiadi U. Onyike, Sub H. Subramony, Jeremy D. Schmahmann, Brian J. Soher, Peter B. Barker, Thomas H. Mareci, Eva‐Maria Ratai, Lynn E. Eberly, Gülin Öz   +19 more
wiley   +1 more source

FocuS-MN: Focusing on Underwater Signal Denoising via Sequential Memory Networks with Learnable Resampling

Journal of Marine Science and Engineering
The coupling of non-stationary marine noise and complex ship-radiated signals makes high-fidelity signal recovery exceptionally difficult. Existing deep learning methods often prioritize objective metrics, such as the Scale-Invariant Signal-to-Noise ...
Shouao Gu, Zitong Li, Jun Tang
doaj   +1 more source

T1 Over Squared Proton Density Ratio to Characterize Multiple Sclerosis Lesions

Annals of Clinical and Translational Neurology, EarlyView.
ABSTRACT Objective Differentiating remyelinated from demyelinated lesions in MS remains challenging without histological confirmation. This study introduces the T1‐to‐PD2 ratio (TPR) imaging approach and evaluates its ability to characterize MS lesions alongside other quantitative MRI (qMRI) metrics. Methods Thirty individuals with MS (mean age: 47.5 ± 
Sarah J. Wright, Scotty G. McKay, Jean Ramos Bou, Fen Bao, Vivian B. Truong, Chenyang Li, Li Jiang, Anza B. Memon, E. Mark Haacke, Yulin Ge, Yongsheng Chen   +10 more
wiley   +1 more source