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https://www.readbyqxmd.com/read/28633131/dose-calculation-using-haar-wavelets-with-buildup-correction
#1
K Belkadhi, K Elhamdi, M Bhar, K Manai
In this work, we focus on the buildup correction of dose calculation using Haar wavelets in the Tunisian gamma irradiation facility. The buildup effect of gamma rays was used to adjust absorbed dose calculation for different depth in the irradiated products. A buildup study with different product densities was carried out to generalize the dose adjustment approach to any product at any depth.
June 15, 2017: Applied Radiation and Isotopes
https://www.readbyqxmd.com/read/28629202/a-novel-extreme-learning-machine-classification-model-for-e-nose-application-based-on-the-multiple-kernel-approach
#2
Yulin Jian, Daoyu Huang, Jia Yan, Kun Lu, Ying Huang, Tailai Wen, Tanyue Zeng, Shijie Zhong, Qilong Xie
A novel classification model, named the quantum-behaved particle swarm optimization (QPSO)-based weighted multiple kernel extreme learning machine (QWMK-ELM), is proposed in this paper. Experimental validation is carried out with two different electronic nose (e-nose) datasets. Being different from the existing multiple kernel extreme learning machine (MK-ELM) algorithms, the combination coefficients of base kernels are regarded as external parameters of single-hidden layer feedforward neural networks (SLFNs)...
June 19, 2017: Sensors
https://www.readbyqxmd.com/read/28627137/effect-of-sympathetic-nerve-blockade-on-low-frequency-oscillations-of-forearm-and-leg-skin-blood-flow-in-healthy-humans
#3
Gary J Hodges, Matthew M Mallette, Zachary T Martin, Andrew T Del Pozzi
Examine the effect of inhibiting sympathetic function on cutaneous vasomotion in the forearm and leg METHODS: Intradermal microdialysis fibres were placed in the forearm and leg, one as an untreated control (lactated Ringer's) the other perfused with bretylium tosylate to block sympathetic nerves. Skin blood flow was monitored using laser-Doppler flowmetry. Baseline was collected for 10 min before local skin temperature was increased to 42°C. Spectral analysis was performed using a Morlet wavelet RESULTS: Bretylium tosylate increased skin blood flow during baseline in the forearm (d=1...
June 19, 2017: Microcirculation: the Official Journal of the Microcirculatory Society, Inc
https://www.readbyqxmd.com/read/28626082/significant-role-of-the-cardio-postural-interaction-in-blood-pressure-regulation-during-standing
#4
Da Xu, Ajay Verma, Amanmeet Garg, Michelle Bruner, Reza Fazel-Rezai, Andrew P Blaber, Kouhyar Tavakolian
Cardiovascular and postural control systems have been studied independently despite the increasing evidence showing the importance of cardio-postural interaction in blood pressure regulation. In this study, we aimed to assess the role of cardio-postural interaction in relation to cardiac baroreflex in blood pressure regulation under orthostatic stress before and after mild exercise. Physiological variables representing cardiovascular control (heart rate and systolic blood pressure), lower limb muscle activation (electromyography), and postural sway (center of pressure derived from force and moment data during sway) were measured from 17 healthy participants (25±2 years; 8 females) during a sit-to-stand test before and after sub-maximal exercise...
June 16, 2017: American Journal of Physiology. Heart and Circulatory Physiology
https://www.readbyqxmd.com/read/28616384/comparison-of-large-scale-human-brain-functional-and-anatomical-networks-in-schizophrenia
#5
Brent G Nelson, Danielle S Bassett, Jazmin Camchong, Edward T Bullmore, Kelvin O Lim
Schizophrenia is a disease with disruptions in thought, emotion, and behavior. The dysconnectivity hypothesis suggests these disruptions are due to aberrant brain connectivity. Many studies have identified connectivity differences but few have been able to unify gray and white matter findings into one model. Here we develop an extension of the Network-Based Statistic (NBS) called NBSm (Multimodal Network-based statistic) to compare functional and anatomical networks in schizophrenia. Structural, resting functional, and diffusion magnetic resonance imaging data were collected from 29 chronic patients with schizophrenia and 29 healthy controls...
2017: NeuroImage: Clinical
https://www.readbyqxmd.com/read/28615744/regularity-of-non-stationary-subdivision-a-matrix-approach
#6
M Charina, C Conti, N Guglielmi, V Protasov
In this paper, we study scalar multivariate non-stationary subdivision schemes with integer dilation matrix M and present a unifying, general approach for checking their convergence and for determining their Hölder regularity (latter in the case [Formula: see text]). The combination of the concepts of asymptotic similarity and approximate sum rules allows us to link stationary and non-stationary settings and to employ recent advances in methods for exact computation of the joint spectral radius. As an application, we prove a recent conjecture by Dyn et al...
2017: Numer Math (Heidelb)
https://www.readbyqxmd.com/read/28613239/time-frequency-analysis-of-non-stationary-biological-signals-with-sparse-linear-regression-based-fourier-linear-combiner
#7
Yubo Wang, Kalyana C Veluvolu
It is often difficult to analyze biological signals because of their nonlinear and non-stationary characteristics. This necessitates the usage of time-frequency decomposition methods for analyzing the subtle changes in these signals that are often connected to an underlying phenomena. This paper presents a new approach to analyze the time-varying characteristics of such signals by employing a simple truncated Fourier series model, namely the band-limited multiple Fourier linear combiner (BMFLC). In contrast to the earlier designs, we first identified the sparsity imposed on the signal model in order to reformulate the model to a sparse linear regression model...
June 14, 2017: Sensors
https://www.readbyqxmd.com/read/28613208/ensemble-methods-with-outliers-for-phonocardiogram-classification
#8
Masun Nabhan Homsi, Philip Warrick
Heart sound classification and analysis play an important role in early diagnosis and prevention of cardiovascular disease. To this end, this paper introduces a novel method for automatic classification of normal and abnormal heart sound recordings. Signals are first preprocessed to extract a total of 131 features in time, frequency, wavelet and statistical domains from the entire signal and from the timings of the states. Outlier signals are then detected and separated from those with a standard range using interquartile range algorithm...
June 14, 2017: Physiological Measurement
https://www.readbyqxmd.com/read/28610698/denoising-portal-images-by-minimizing-the-sure-estimator-on-a-parameterized-family-of-shrinkage-functions
#9
Antonio González-López, Pedro Campos-Morcillo
The number of verification portal images in radiotherapy has increased in the last years. On the other hand, radiation delivered during imaging is not confined to the treatment volumes, but also affects the surrounding organs and tissues. In order to reduce the overall radiation dose due to imaging, one approach would be to reduce the dose per image, but noise would increase and the quality of portal images would reduce. The limited quality of portal images makes it difficult to propose a reduction of dose if there is no way to effectively reduce noise...
June 2017: Physica Medica: PM
https://www.readbyqxmd.com/read/28607956/a-wavelet-based-gaussian-method-for-energy-dispersive-x-ray-fluorescence-spectrum
#10
Pan Liu, Xiaoyan Deng, Xin Tang, Shijian Shen
This paper presents a wavelet-based Gaussian method (WGM) for the peak intensity estimation of energy dispersive X-ray fluorescence (EDXRF). The relationship between the parameters of Gaussian curve and the wavelet coefficients of Gaussian peak point is firstly established based on the Mexican hat wavelet. It is found that the Gaussian parameters can be accurately calculated by any two wavelet coefficients at the peak point which has to be known. This fact leads to a local Gaussian estimation method for spectral peaks, which estimates the Gaussian parameters based on the detail wavelet coefficients of Gaussian peak point...
May 2017: Heliyon
https://www.readbyqxmd.com/read/28607617/influence-of-myopotential-interference-on-the-wavelet-discrimination-algorithm-in-implantable-cardioverter-defibrillator
#11
Kazuya Mizukami, Hisashi Yokoshiki, Hirofumi Mitsuyama, Masaya Watanabe, Taro Tenma, Rui Kamada, Masayuki Takahashi, Ryo Sasaki, Motoki Maeno, Hiroyuki Tsutsui
BACKGROUND: Wavelet is a morphology-based algorithm for detecting ventricular tachycardia. The electrogram (EGM) source of the Wavelet algorithm is nominally programmed with the Can-RV coil configuration, which records a far-field ventricular potential. Therefore, it may be influenced by myopotential interference. METHODS: We performed a retrospective review of 40 outpatients who had an implantable cardioverter-defibrillator (ICD) with the Wavelet algorithm. The percent-match score of the Wavelet algorithm was measured during the isometric chest press by pressing the palms together...
June 2017: Journal of Arrhythmia
https://www.readbyqxmd.com/read/28605863/quantitative-assessment-of-the-impacts-of-climate-change-and-human-activities-on-runoff-change-in-a-typical-karst-watershed-sw-china
#12
Luhua Wu, Shijie Wang, Xiaoyong Bai, Weijun Luo, Yichao Tian, Cheng Zeng, Guangjie Luo, Shiyan He
The Yinjiang River watershed is a typical karst watershed in Southwest China. The present study explored runoff change and its responses to different driving factors in the Yinjiang River watershed over the period of 1984 to 2015. The methods of cumulative anomaly, continuous wavelet analysis, Mann-Kendall rank correlation trend test, and Hurst exponent were applied to analyze the impacts of climate change and human activities on runoff change. The contributions of climate change and human activities to runoff change were quantitatively assessed using the comparative method of the slope changing ratio of cumulative quantity (SCRCQ)...
June 8, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28599255/research-on-two-port-network-of-wavelet-transform-processor-using-surface-acoustic-wavelet-devices-and-its-application
#13
Shoubing Liu, Wenke Lu, Changchun Zhu
The goal of this research is to study two-port network of wavelet transform processor (WTP) using surface acoustic wave (SAW) devices and its application. The motive was prompted by the inconvenience of the long research and design cycle and the huge research funding involved with traditional method in this field, which were caused by the lack of the simulation and emulation method of WTP using SAW devices. For this reason, we introduce the two-port network analysis tool, which has been widely used in the design and analysis of SAW devices with uniform interdigital transducers (IDTs)...
May 29, 2017: Ultrasonics
https://www.readbyqxmd.com/read/28596962/a-novel-ecg-eigenvalue-detection-algorithm-based-on-wavelet-transform
#14
Ziran Peng, Guojun Wang
This study investigated an electrocardiogram (ECG) eigenvalue automatic analysis and detection method; ECG eigenvalues were used to reverse the myocardial action potential in order to achieve automatic detection and diagnosis of heart disease. Firstly, the frequency component of the feature signal was extracted based on the wavelet transform, which could be used to locate the signal feature after the energy integral processing. Secondly, this study established a simultaneous equations model of action potentials of the myocardial membrane, using ECG eigenvalues for regression fitting, in order to accurately obtain the eigenvalue vector of myocardial membrane potential...
2017: BioMed Research International
https://www.readbyqxmd.com/read/28596697/wavelet-transforms-on-gelfand-shilov-spaces-and-concrete-examples
#15
Naohiro Fukuda, Tamotu Kinoshita, Kazuhisa Yoshino
In this paper, we study the continuity properties of wavelet transforms in the Gelfand-Shilov spaces with the use of a vanishing moment condition. Moreover, we also compute the Fourier transforms and the wavelet transforms of concrete functions in the Gelfand-Shilov spaces.
2017: Journal of Inequalities and Applications
https://www.readbyqxmd.com/read/28596461/classification-of-pulmonary-pathology-from-breath-sounds-using-the-wavelet-packet-transform-and-an-extreme-learning-machine
#16
Rajkumar Palaniappan, Kenneth Sundaraj, Sebastian Sundaraj, N Huliraj, S S Revadi
BACKGROUND: Auscultation is a medical procedure used for the initial diagnosis and assessment of lung and heart diseases. From this perspective, we propose assessing the performance of the extreme learning machine (ELM) classifiers for the diagnosis of pulmonary pathology using breath sounds. METHODS: Energy and entropy features were extracted from the breath sound using the wavelet packet transform. The statistical significance of the extracted features was evaluated by one-way analysis of variance (ANOVA)...
June 8, 2017: Biomedizinische Technik. Biomedical Engineering
https://www.readbyqxmd.com/read/28594936/climatic-and-drought-characteristics-in-the-loess-hilly-gully-region-of-china-from-1957-to-2014
#17
Xingkai Zhao, Zengyao Li, Qingke Zhu, Danhong Zhu, Huifang Liu
The loess hilly-gully region is a focus region of the "Grain for Green" program in China. Drought is the main problem in the study region. Precipitation and temperature are two indicators that directly characterize climatic drought. A thorough analysis of the precipitation, temperature and drought characteristics of the loess hilly-gully region can clarify the current water and heat conditions in the region to improve regional water resource management and provide a reliable reference for effectively improving water use efficiency...
2017: PloS One
https://www.readbyqxmd.com/read/28594352/automatic-artifact-removal-in-eeg-of-normal-and-demented-individuals-using-ica-wt-during-working-memory-tasks
#18
Noor Kamal Al-Qazzaz, Sawal Hamid Bin Mohd Ali, Siti Anom Ahmad, Mohd Shabiul Islam, Javier Escudero
Characterizing dementia is a global challenge in supporting personalized health care. The electroencephalogram (EEG) is a promising tool to support the diagnosis and evaluation of abnormalities in the human brain. The EEG sensors record the brain activity directly with excellent time resolution. In this study, EEG sensor with 19 electrodes were used to test the background activities of the brains of five vascular dementia (VaD), 15 stroke-related patients with mild cognitive impairment (MCI), and 15 healthy subjects during a working memory (WM) task...
June 8, 2017: Sensors
https://www.readbyqxmd.com/read/28593391/wavelet-decomposition-analysis-in-the-two-flash-multifocal-erg-in-early-glaucoma-a-comparison-to-ganglion-cell-analysis-and-visual-field
#19
Livia M Brandao, Matthias Monhart, Andreas Schötzau, Anna A Ledolter, Anja M Palmowski-Wolfe
PURPOSE: To further improve analysis of the two-flash multifocal electroretinogram (2F-mfERG) in glaucoma in regard to structure-function analysis, using discrete wavelet transform (DWT) analysis. METHODS: Sixty subjects [35 controls and 25 primary open-angle glaucoma (POAG)] underwent 2F-mfERG. Responses were analyzed with the DWT. The DWT level that could best separate POAG from controls was compared to the root-mean-square (RMS) calculations previously used in the analysis of the 2F-mfERG...
June 7, 2017: Documenta Ophthalmologica. Advances in Ophthalmology
https://www.readbyqxmd.com/read/28593191/at-what-latency-does-the-phase-of-brain-oscillations-influence-perception
#20
Sasskia Brüers, Rufin VanRullen
Recent evidence has shown a rhythmic modulation of perception: prestimulus ongoing electroencephalography (EEG) phase in the θ (4-8 Hz) and α (8-13 Hz) bands has been directly linked with fluctuations in target detection. In fact, the ongoing EEG phase directly reflects cortical excitability: it acts as a gating mechanism for information flow at the neuronal level. Consequently, the key phase modulating perception should be the one present in the brain when the stimulus is actually being processed. Most previous studies, however, reported phase modulation peaking 100 ms or more before target onset...
May 2017: ENeuro
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