Note: One order of magnitude better signal-to-noise ratio for neutron backscattering

2017 ◽  
Vol 88 (3) ◽  
pp. 036105 ◽  
Author(s):  
Markus Appel ◽  
Bernhard Frick
Keyword(s):  
Signal To Noise Ratio ◽  
Signal To Noise ◽  
Order Of Magnitude ◽  
Noise Ratio

scholarly journals Counterfactual ghost imaging

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Jonte R. Hance ◽  
John Rarity
Keyword(s):  
Signal To Noise Ratio ◽  
Ghost Imaging ◽  
Signal To Noise ◽  
Interesting Phenomenon ◽  
Order Of Magnitude ◽  
Noise Ratio

AbstractWe give a protocol for ghost imaging in a way that is always counterfactual—while imaging an object, no light interacts with that object. This extends the idea of counterfactuality beyond communication, showing how this interesting phenomenon can be leveraged for metrology. Given, in the infinite limit, no photons ever go to the imaged object, it presents a method of imaging even the most light-sensitive of objects without damaging them. Even when not in the infinite limit, it still provides a many-fold improvement in visibility and signal-to-noise ratio over previous protocols, with over an order of magnitude reduction in absorbed intensity.

Proposal for a Laue lens with quasi-mosaic crystalline tiles

2011 ◽  
Vol 44 (6) ◽  
pp. 1255-1258 ◽  
Author(s):  
Vincenzo Guidi ◽  
Valerio Bellucci ◽  
Riccardo Camattari ◽  
Ilaria Neri
Keyword(s):  
High Resolution ◽  
Crystal Size ◽  
Signal To Noise Ratio ◽  
Signal To Noise ◽  
Laue Lens ◽  
Crystalline Anisotropy ◽  
Order Of Magnitude ◽  
Mosaic Crystals ◽  
Noise Ratio ◽  
Very High

Quasi-mosaicity is an effect of secondary bending within a crystal driven by crystalline anisotropy. This effect can be used to fabricate a series of curved crystals for the realization of a Laue lens. It is highlighted that crystals bent by the quasi-mosaic effect allow very high resolution focusing with respect to mosaic crystals. Under the same conditions for energy passband, crystal size and flux of incident photons, a Laue lens based on quasi-mosaic crystals would increase the signal-to-noise ratio by about an order of magnitude compared to the same lens with mosaic crystals. Moreover, no mosaic defocusing occurs for quasi-mosaic crystals.

scholarly journals Signal transmission through the dark-adapted retina of the toad (Bufo marinus). Gain, convergence, and signal/noise.

1990 ◽  
Vol 95 (4) ◽  
pp. 717-732 ◽  
Author(s):  
D R Copenhagen ◽  
S Hemilä ◽  
T Reuter
Keyword(s):  
Ganglion Cells ◽  
Signal To Noise Ratio ◽  
Signal Transmission ◽  
Absolute Threshold ◽  
Spatial Summation ◽  
Bipolar Cells ◽  
Horizontal Cells ◽  
Signal To Noise ◽  
Order Of Magnitude ◽  
Noise Ratio

Responses to light were recorded from rods, horizontal cells, and ganglion cells in dark-adapted toad eyecups. Sensitivity was defined as response amplitude per isomerization per rod for dim flashes covering the excitatory receptive field centers. Both sensitivity and spatial summation were found to increase by one order of magnitude between rods and horizontal cells, and by two orders of magnitude between rods and ganglion cells. Recordings from two hyperpolarizing bipolar cells showed a 20 times response increase between rods and bipolars. At absolute threshold for ganglion cells (Copenhagen, D.R., K. Donner, and T. Reuter. 1987. J. Physiol. 393:667-680) the dim flashes produce 10-50-microV responses in the rods. The cumulative gain exhibited at each subsequent synaptic transfer from the rods to the ganglion cells serves to boost these small amplitude signals to the level required for initiation of action potentials in the ganglion cells. The convergence of rod signals through increasing spatial summation serves to decrease the variation of responses to dim flashes, thereby increasing the signal-to-noise ratio. Thus, at absolute threshold for ganglion cells, the convergence typically increases the maximal signal-to-noise ratio from 0.6 in rods to 4.6 in ganglion cells.

Amplitude and Frequency Dependence of the Signal-to-Noise Ratio in LDV Measurements

2011 ◽  
Author(s):  
Patrick F. O’Malley ◽  
Joseph F. Vignola ◽  
John A. Judge
Keyword(s):  
Vibration Amplitude ◽  
Signal To Noise Ratio ◽  
Speckle Pattern ◽  
Laser Doppler Vibrometer ◽  
Signal To Noise ◽  
Velocity Response ◽  
Order Of Magnitude ◽  
Noise Ratio ◽  
Ldv Measurement ◽  
The Relationship

When making measurements using many sensors, it is expected that, within normal operating ranges, the signal-to-noise ratio is approximately linear (i.e. 20 dB/decade). This generality does not hold, however, when making measurements using a laser Doppler vibrometer (LDV). If the velocity of the target of an LDV measurement increases by an order of magnitude, changes in the speckle pattern will introduce noise into the measurand. An experiment was conducted using an LDV system to measure the velocity response of a speaker excited over several orders of magnitude in both frequency and amplitude. Results are presented showing the relationship between signal-to-noise ratio and vibration amplitude.

Towards Novel Graphene-Enabled Diagnostic Assays with Improved Signal-to-Noise Ratio

MRS Advances ◽  
2017 ◽  
Vol 2 (60) ◽  
pp. 3733-3739 ◽  
Author(s):  
Savannah J. Afsahi ◽  
Lauren E. Locascio ◽  
Deng Pan ◽  
Yingning Gao ◽  
Amy E. Walker ◽  
...  
Keyword(s):  
State Of The Art ◽  
Signal To Noise Ratio ◽  
Chemical Vapor ◽  
Precision Measurements ◽  
Signal To Noise ◽  
Electronics Assembly ◽  
Diagnostic Assays ◽  
Large Numbers ◽  
Order Of Magnitude ◽  
Noise Ratio

ABSTRACTLarge numbers of high quality graphene transistors were fabricated by chemical vapor deposition and packaged into a standard electronics assembly, enabling the readout of graphene properties on the benchtop. After chemical functionalization, these sensors demonstrate sensitivity into the pM range to inflammation (IL6) and Zika virus (ZIKV NS1) biomarkers. Signal-to-noise ratio (SNR) of graphene biosensors is over an order of magnitude greater than established diagnostic and biophysical assays, namely ELISA and BLI respectively. High precision measurements of protein kinetics captured using this technology, commercially available as the AGILE R100, are comparable to both clinical diagnostic and state-of-the-art biomolecule characterization tools. These results demonstrate that graphene-based platforms are highly attractive biological sensors for next generation diagnostics.

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 :

Speech Reception in the Presence of Classroom Noise

1979 ◽  
Vol 10 (4) ◽  
pp. 221-230 ◽  
Author(s):  
Veronica Smyth
Keyword(s):  
Signal To Noise Ratio ◽  
Learning Processes ◽  
Speech Discrimination ◽  
Signal To Noise ◽  
Speech Reception ◽  
Monosyllabic Words ◽  
Noise Ratio

Three hundred children from five to 12 years of age were required to discriminate simple, familiar, monosyllabic words under two conditions: 1) quiet, and 2) in the presence of background classroom noise. Of the sample, 45.3% made errors in speech discrimination in the presence of background classroom noise. The effect was most marked in children younger than seven years six months. The results are discussed considering the signal-to-noise ratio and the possible effects of unwanted classroom noise on learning processes.

Quantifying the Effects of Background Speech Babble on Preschool Children's Novel Word Learning in a Multisession Paradigm: A Preliminary Study

2020 ◽  
Vol 63 (1) ◽  
pp. 345-356
Author(s):  
Meital Avivi-Reich ◽  
Megan Y. Roberts ◽  
Tina M. Grieco-Calub
Keyword(s):  
Word Learning ◽  
Signal To Noise Ratio ◽  
Preschool Age ◽  
Exposure Condition ◽  
Signal To Noise ◽  
Verbal Recall ◽  
Referent Selection ◽  
Main Effect ◽  
Noise Ratio ◽  
Novel Word Learning

Purpose This study tested the effects of background speech babble on novel word learning in preschool children with a multisession paradigm. Method Eight 3-year-old children were exposed to a total of 8 novel word–object pairs across 2 story books presented digitally. Each story contained 4 novel consonant–vowel–consonant nonwords. Children were exposed to both stories, one in quiet and one in the presence of 4-talker babble presented at 0-dB signal-to-noise ratio. After each story, children's learning was tested with a referent selection task and a verbal recall (naming) task. Children were exposed to and tested on the novel word–object pairs on 5 separate days within a 2-week span. Results A significant main effect of session was found for both referent selection and verbal recall. There was also a significant main effect of exposure condition on referent selection performance, with more referents correctly selected for word–object pairs that were presented in quiet compared to pairs presented in speech babble. Finally, children's verbal recall of novel words was statistically better than baseline performance (i.e., 0%) on Sessions 3–5 for words exposed in quiet, but only on Session 5 for words exposed in speech babble. Conclusions These findings suggest that background speech babble at 0-dB signal-to-noise ratio disrupts novel word learning in preschool-age children. As a result, children may need more time and more exposures of a novel word before they can recognize or verbally recall it.

Sign in / Sign up

Export Citation Format

Share Document