scholarly journals Damage Characterization of Composite Structures Using Difference Peak Signal-to-Noise Ratio as a Function of Variable Wavelets (ΔPSNR-ΔW)

Engineering ◽  
2016 ◽  
Vol 08 (04) ◽  
pp. 204-225 ◽  
Author(s):  
Mahmoud Zaki Iskandarani
Keyword(s):  
Composite Structures ◽  
Signal To Noise Ratio ◽  
Signal To Noise ◽  
Damage Characterization ◽  
Noise Ratio

scholarly journals Signal to Noise Ratio Characterization of Coherent Doppler Lidar Backscattered Signals

2016 ◽  
Vol 119 ◽  
pp. 17014 ◽  
Author(s):  
Sameh Abdelazim ◽  
David Santoro ◽  
Mark Arend ◽  
Fred Moshary ◽  
Sam Ahmed
Keyword(s):  
Signal To Noise Ratio ◽  
Doppler Lidar ◽  
Signal To Noise ◽  
Coherent Doppler Lidar ◽  
Noise Ratio ◽  
Backscattered Signals

scholarly journals DISPOSABLE SYSTEM FOR IN-VIVO MECHANICAL CHARACTERIZATION OF SOFT TISSUES BASED ON VOLUME MEASUREMENT

2018 ◽  
Vol 18 (04) ◽  
pp. 1850037 ◽  
Author(s):  
SEYED ALI ELAHI ◽  
NATHANAEL CONNESSON ◽  
YOHAN PAYAN
Keyword(s):  
Mechanical Properties ◽  
Soft Tissues ◽  
Signal To Noise Ratio ◽  
Volume Measurement ◽  
Optical Measurements ◽  
Signal To Noise ◽  
Noise Ratio ◽  
Apex Height

In-vivo characterization of soft tissues is a key step toward biomechanical simulation and planning of intra-operative assisted surgery. To achieve this, aspiration method is a standard technique: tissue is aspirated through a hole while measuring the pressure and associated apex height. An inverse problem is then solved to identify the material mechanical properties. In the literature, the apex height is usually measured using a camera, which induces design difficulties, in particular in regards on the required sterilization process for in-vivo measurements. In this paper, the idea is to replace the apex height optical measurement by the measurement of the aspirated tissue volume. The proposed method enables to reduce the system head to a simple tube: sterilizations becomes easy and the system is disposable after use. The proposed system is thus the simplest, lightest and cheapest one could achieve. It is also to the authors knowledge the first time ever in aspiration method that the aspired volume is the extracted data. As the data signal-to-noise ratio is the main factor impacting any applied inverse method when extracting the mechanical properties, the aim of this work is to assess and compare the experimental signal-to-noise ratio in the raw volume measurements obtained either optically or with the method proposed. Explicit results of inverse methods using volumes as input data are not presented in this paper for concision purpose. The effects on accuracy of various experimental parameters has been investigated and quantified: the volume measurement has proved to present a same order or even better signal-to-noise ratio compared to optical measurements.

scholarly journals Characterization of Roasted Coffee Aroma by Optimizing Roaster Parameters

2018 ◽  
Vol 8 (1) ◽  
pp. 23-29
Author(s):  
Firman Ridwan ◽  
Roni Novison
Keyword(s):  
Moisture Content ◽  
Incubation Time ◽  
Rotational Speed ◽  
Signal To Noise Ratio ◽  
Signal To Noise ◽  
Roasted Coffee ◽  
Minimum Number ◽  
Noise Ratio

This study was aimed to improve the quality of aroma of roasted coffee by using Taguchi's design as experimental technique. The roaster parameters evaluated were temperature, incubation time, moisture content and cylinder rotational speed. An orthogonal array L9, signal to noise ratio and ANOVA were employed to investigate the influence of the roaster parameters. The results showed that the optimal roasted coffee aroma was produced at a temperature of 170◦C, incubation time of 14 minutes, moisture content of 6% (v/w) and cylinder rotational speed of 50 rpm. The most to less significant roasting parameters as observed in this study were as follows: temperature, incubation time, moisture content and cylinder rotational speed. Furthermore, the results showed that the Taguchi design was better than the full experimental design in solving experiments with a minimum number. Keywords: ANOVA, Coffee roaster, Roasted coffee aroma, Signal to noise ratio, Taguchi technique

A Bispectral Analysis of the Radio Emissions of Pulsar J0437-4715

2020 ◽  
Vol 09 (04) ◽  
pp. 2050018
Author(s):  
Alexander Faustmann ◽  
Jacki Gilmore ◽  
Vereese van Tonder ◽  
Maciej Serylak
Keyword(s):  
Signal To Noise Ratio ◽  
Gaussian Model ◽  
Higher Order ◽  
Detection Methods ◽  
High Signal ◽  
Signal To Noise ◽  
Noise Ratio ◽  
Alternative Detection ◽  
Higher Order Spectra

A combination of the very low signal-to-noise ratio and the very large parameter space spanned by pulsar emissions makes pulsar detection a challenging task. Currently, brute force parameter searches are often used for pulsar detection and a cyclostationary Gaussian model is assumed for pulsar emissions. Higher-Order spectra offer high signal-to-noise ratio domains in problems where the desired signal is polluted by Gaussian noise. The presence of nonzero higher-order spectral components in pulsar bursts may offer alternative detection methods. This work presents a review of higher-order statistics and offers a motivation for their use in the characterization of pulsar bursts. A dish from the MeerKAT telescope was used to acquire recorded radio bursts from pulsar J0437-4715. These bursts were found to contain nonzero bispectral components that were dispersed in the same way as the components of the power spectrum.

Determination of the Best Emulsion for the Microscopy of Crystals

1981 ◽  
Vol 39 ◽  
pp. 32-33
Author(s):  
David A. Grano ◽  
Kenneth H. Downing
Keyword(s):  
Spatial Frequency ◽  
Information Transfer ◽  
Signal To Noise Ratio ◽  
Experimental Situation ◽  
Photographic Emulsion ◽  
Modulation Transfer ◽  
Signal To Noise ◽  
Frequency Space ◽  
Noise Ratio

The retrieval of high-resolution information from images of biological crystals depends, in part, on the use of the correct photographic emulsion. We have been investigating the information transfer properties of twelve emulsions with a view toward 1) characterizing the emulsions by a few, measurable quantities, and 2) identifying the “best” emulsion of those we have studied for use in any given experimental situation. Because our interests lie in the examination of crystalline specimens, we've chosen to evaluate an emulsion's signal-to-noise ratio (SNR) as a function of spatial frequency and use this as our critereon for determining the best emulsion.The signal-to-noise ratio in frequency space depends on several factors. First, the signal depends on the speed of the emulsion and its modulation transfer function (MTF). By procedures outlined in, MTF's have been found for all the emulsions tested and can be fit by an analytic expression 1/(1+(S/S0)2). Figure 1 shows the experimental data and fitted curve for an emulsion with a better than average MTF. A single parameter, the spatial frequency at which the transfer falls to 50% (S0), characterizes this curve.

Experiments in Bright-Field Imaging with Hollow-Cone Illumination

1981 ◽  
Vol 39 ◽  
pp. 226-227
Author(s):  
W. Kunath ◽  
K. Weiss ◽  
E. Zeitler
Keyword(s):  
Signal To Noise Ratio ◽  
Carbon Support ◽  
Electronic System ◽  
Optic Axis ◽  
Hollow Cone ◽  
Signal To Noise ◽  
Bright Field ◽  
Noise Ratio ◽  
Single Field ◽  
Field Imaging

Bright-field images taken with axial illumination show spurious high contrast patterns which obscure details smaller than 15 ° Hollow-cone illumination (HCI), however, reduces this disturbing granulation by statistical superposition and thus improves the signal-to-noise ratio. In this presentation we report on experiments aimed at selecting the proper amount of tilt and defocus for improvement of the signal-to-noise ratio by means of direct observation of the electron images on a TV monitor.Hollow-cone illumination is implemented in our microscope (single field condenser objective, Cs = .5 mm) by an electronic system which rotates the tilted beam about the optic axis. At low rates of revolution (one turn per second or so) a circular motion of the usual granulation in the image of a carbon support film can be observed on the TV monitor. The size of the granular structures and the radius of their orbits depend on both the conical tilt and defocus.

Information capacity and bandwidth limitations in the SEM

1989 ◽  
Vol 47 ◽  
pp. 84-85
Author(s):  
D. C. Joy ◽  
R. D. Bunn
Keyword(s):  
Signal To Noise Ratio ◽  
Critical Dimension ◽  
Information Capacity ◽  
Acquisition Time ◽  
Signal To Noise ◽  
Sem Image ◽  
Probe Size ◽  
Minimum Number ◽  
Noise Ratio ◽  
Signal Channel

The information available from an SEM image is limited both by the inherent signal to noise ratio that characterizes the image and as a result of the transformations that it may undergo as it is passed through the amplifying circuits of the instrument. In applications such as Critical Dimension Metrology it is necessary to be able to quantify these limitations in order to be able to assess the likely precision of any measurement made with the microscope.The information capacity of an SEM signal, defined as the minimum number of bits needed to encode the output signal, depends on the signal to noise ratio of the image - which in turn depends on the probe size and source brightness and acquisition time per pixel - and on the efficiency of the specimen in producing the signal that is being observed. A detailed analysis of the secondary electron case shows that the information capacity C (bits/pixel) of the SEM signal channel could be written as :

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