scholarly journals Method and Device Based on Multiscan for Measuring the Geometric Parameters of Objects

Processes ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 24
Author(s):  
Michael Yurievich Alies ◽  
Yuriy Konstantinovich Shelkovnikov ◽  
Milan Sága ◽  
Milan Vaško ◽  
Ivan Kuric ◽  
...  
Keyword(s):  
High Sensitivity ◽  
Optoelectronic Device ◽  
Discrete Analog ◽  
Video Signal ◽  
Geometric Parameters ◽  
Precision Measurements ◽  
Dual Nature ◽  
Step Voltage ◽  
Accuracy Of Measurements ◽  
Discrete Structures

The article deals with the issues of improving the accuracy of measurements of the geometric parameters of objects by optoelectronic systems, based on a television multiscan. A mathematical model of a multiscan with scanistor activation is developed, expressions for its integral output current and video signal are obtained, and the mechanism of their formation is investigated. An expression for the video signal is obtained that reflects the dual nature of the discrete–continuous multiscan structure: the video signal can have a discrete (pulse) or analog (continuous) form, depending on the step voltage between the photodiode cells of the multiscan. A Vernier discrete–analog method for measuring the parameters of the light zone on a multiscan is proposed, in which in order to increase the accuracy of the measurements, the location of the video pulse is determined relative to the neighboring reference pulses of a rigid geometric raster due to the slope of the discrete structure of the multiscan. It is established that the Vernier method enables one to make precision measurements of the coordinates, dimensions, and movements of the light zones by an overlay on a video raster of reference pulses from cells—a uniform sequence of Vernier pulses with a recurrence interval, followed by determining the number of the Vernier pulse that coincides with the raster pulse. An optoelectronic device based on a discrete–continuous multiscan, implemented on the basis of the proposed Vernier method of measuring the coordinates of the light zones, which has a high sensitivity to movement, is characteristic of continuous structures, and has increased stability and linearity of the coordinate characteristics typical for discrete structures, is developed.

Spherical gravity inversion of GRAIL data

2021 ◽  
Author(s):  
Lev Chepigo ◽  
Ivan Lygin ◽  
Andrey Bulychev ◽  
Kuznetsov Kirill
Keyword(s):  
Variable Parameter ◽  
High Sensitivity ◽  
Gravity Inversion ◽  
Long Duration ◽  
Accuracy Of Measurements ◽  
Lunar Basalts ◽  
Celestial Bodies ◽  
Satellite Missions ◽  
High Degree ◽  
Selection Of

<p>Taking into account sphericity is one of the most relevant questions of interest for gravity researchers today. It’s especially important in data analysis of regional surveys and satellite missions.</p><p>Modern satellite missions are characterized by high accuracy of measurements, as well as a high degree of detail, which makes it possible to construct detailed grid density models of Earth and Moon, however, when automating this process, the following problems arise:</p><p>- long duration of the inversion process;</p><p>- need for a large amount of RAM when using standard approaches to solving the linear inverse problem of gravity prospecting for grid models;</p><p>- high sensitivity of gravity inversion algorithms to the upper cells;</p><p>The first problem can be solved by inverting of gravity in the spectral domain using the fast Fourier transform. In this case, the time complexity of the inversion algorithms is reduced by times, which significantly accelerates the selection of the model.     </p><p>To reduce the memory used, it is necessary to memorize the gravity spectrum for only one cell for each pair of coordinates depth - latitude, since cells with at the same depth and latitude have the same gravitational effects, shifted by the step of cells in the grid model.</p><p>Finally, to increase the sensitivity of the inversion algorithms to deep cells, you can use the variable parameter of the gradient descent step (learning rate in machine learning), depending on the depth as an exponential or any other function, in combination with regularization.</p><p>The proposed approach was applied to the data of the GRAIL mission, and as a result, a density model of the Moon was constrained with the following grid steps: 0.5<sup>o</sup> in latitude, 0.7<sup>o</sup> (pi / 512) in longitude and 10 km in depth.</p><p>The fitted model was used to estimate the possible parameters of the sources of lunar mascons. It stands to mention the differences in the geometry of the mascon sources, which can be divided into two groups: isometric sources and sources with channels ascending to the surface, through which, probably, lunar basalts entered the surface.</p><p>The proposed approach allows constrain density models of celestial bodies fast enough using a personal computer (less than an hour for a model with the parameters mentioned above), and also takes into account the weak sensitivity of standard inversion algorithms to deep cells.</p>

scholarly journals Inhomogeneity introduced to the climate data series by instrumentation changes of the thermometer shields and rain gauges

2014 ◽  
Vol 44 (1) ◽  
pp. 25-40 ◽  
Author(s):  
Ivana Bartoková ◽  
Monika Kl’ocová ◽  
Juraj Bartok
Keyword(s):  
Global Radiation ◽  
Weather Condition ◽  
High Sensitivity ◽  
Weather Conditions ◽  
Rain Gauge ◽  
Data Series ◽  
Climate Data ◽  
Rain Gauges ◽  
First Choice ◽  
Accuracy Of Measurements

Abstract Recently we can see the trend of introducing a new instrumentation and automatization in the field of information and monitoring systems for the meteorology, hydrology and crisis centers. Nowadays a great number of sensors are used in projects in many countries of various climates. Therefore it is crucial to deeply understand how the change of sensor types will affect the accuracy of measurements and how is accuracy of individual sensor type affected by different weather conditions. We analyzed several screen/shields and rain gauges at the premises of faculty of Meteorology and Climatology of FMFI UK. On the basis of our results we can recommend as a most accurate and not depending on weather condition artificially ventilated screen although it is the most expensive. Our second choice would be a large naturally ventilated shield. In case of Stevenson screens we would recommend painting it with a high gloss coating. Our last choice would be a small naturally ventilated screen because of its high sensitivity to the global radiation. Our first choice of the participating rain gauges would be the weighing rain gauge because of its best results in both cases, of rainfalls up to 2 mm and also over 2 mm. The tipping bucket rain gauge gave also agreeable result in both cases. The optical sensor gave very good results in rainfalls over 2 mm but it is unsuitable for rainfalls up to 2 mm. The radar sensor is also completely unsuitable for low intensity rainfalls and his performance for rainfalls over 2 mm was just average.

scholarly journals High-Speed, High-Sensitivity Optoelectronic Device with Bilayer Electron and Hole Charge Plasma

ACS Photonics ◽  
2014 ◽  
Vol 1 (7) ◽  
pp. 560-569 ◽  
Author(s):  
Bahram Nabet ◽  
Marc Currie ◽  
Pouya Dianat ◽  
Fabio Quaranta ◽  
Adriano Cola
Keyword(s):  
High Speed ◽  
High Sensitivity ◽  
Optoelectronic Device ◽  
Charge Plasma ◽  
Hole Charge

scholarly journals TRENDS IN THE DEVELOPMENT OF DEVICES FOR CONTROL OR GEOMETRIC PARAMETERS OF CONTACT LENSES

2021 ◽  
Vol 6 ◽  
pp. 136-143
Author(s):  
Maria I. Kilnevaya ◽  
Igor O. Mikhailov
Keyword(s):  
Contact Lenses ◽  
Optoelectronic Device ◽  
Geometric Parameters ◽  
Concave Surface ◽  
Contact Control

The article shows the relevance of the control of the geometric parameters of contact lenses. The types of lenses, their advantage over glasses, as well as devices for monitoring the radii of curvature of the concave surface of the lens are considered. The shortcomings of the available devices and methods for monitoring contact lenses are revealed. The principle and features of operation of an optoelectronic device for non-contact control of geometric parameters of contact lenses are proposed.

A Stripline-Type Inductor Used for NMR Detection

2012 ◽  
Vol 198-199 ◽  
pp. 1141-1146
Author(s):  
Bao Song Wu ◽  
Li Zhi Xiao ◽  
Xiao Nan Li ◽  
Bao Xin Guo
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Design Theory ◽  
High Sensitivity ◽  
Geometric Parameters ◽  
Field Homogeneity ◽  
Nuclear Magnetic

This paper tries to design a stripline-type inductor with high sensitivity that is used for micro-fluid in downhole nuclear magnetic resonance (NMR) detection. It discusses the design theory for the probe, and does analysis and simulation to guide the optimal geometric parameters. Radiofrequency B1 field homogeneity is evaluated. Finally, the prototype is made.

scholarly journals Aggregation induced emission based active conjugated imidazole luminogens for visualization of latent fingerprints and multiple anticounterfeiting applications

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
M. K. Ravindra ◽  
G. P. Darshan ◽  
D. R. Lavanya ◽  
K. M. Mahadevan ◽  
H. B. Premkumar ◽  
...  
Keyword(s):  
Large Scale ◽  
Light Exposure ◽  
High Sensitivity ◽  
Poly Vinyl Alcohol ◽  
Scale Production ◽  
Latent Fingerprints ◽  
One Pot ◽  
Aggregation State ◽  
Dual Nature ◽  
Aggregation Induced Emission

AbstractAggregation-induced emission based organic heterocyclic luminogens bearing conjugated electronic structures showed much attention due to its excellent fluorescence in aggregation state. In this communication, a novel conjugated blue light emitting imidazole molecule is synthesized by one pot multicomponent reaction route is reported for the first time. The prepared molecule exhibits a strong fluorescence in aggregation state with exceptional properties, such as high purity, inexpensive, eco-friendly, large scale production, high photostability, etc. By considering these advantages, a new fluorescence based platform has been setup for in-situ visualization of latent fingerprints and its preservation by spray method followed by Poly(vinyl alcohol) masking. A clear and well defined fluorescence fingerprint images are noticed on variety of surfaces by revealing level 1–3 ridge features upon ultraviolet 365 nm light exposure. The dual nature of binding specificity as well as excellent fluorescence properties permits the visualization of latent fingerprints for longer durations (up to 365 days) with superior contrast, high sensitivity, efficiency, selectivity and minimal background hindrance. We further fabricated unclonable invisible security ink for various printing modes on valuable goods for protection against forging. The developed labels are displaying uniform distribution of ink and exceptional stability under various atmospheric environments. The development of long preservative information using aggregation-induced emission based luminogen opens up a new avenue in advanced forensic and data security applications.

scholarly journals Glucocorticoids: Dr. Jekyll and Mr. Hyde of Hippocampal Neuroinflammation

2021 ◽  
Vol 86 (2) ◽  
pp. 156-167
Author(s):  
Alexey P. Bolshakov ◽  
Liya V. Tret’yakova ◽  
Alexey A. Kvichansky ◽  
Natalia V. Gulyaeva
Keyword(s):  
High Sensitivity ◽  
Brain Diseases ◽  
Preliminary Treatment ◽  
Dual Nature ◽  
Mediated Effects ◽  
Anti Inflammatory ◽  
New Hypothesis ◽  
Mechanistic View

Abstract Glucocorticoids (GCs) are an important component of adaptive response of an organism to stressogenic stimuli, a typical stress response being accompanied by elevation of GC levels in blood. Anti-inflammatory effects of GCs are widely used in clinical practice, while pro-inflammatory effects of GCs are believed to underlie neurodegeneration. This is particularly critical for the hippocampus, brain region controlling both cognitive function and emotions/affective behavior, and selectively vulnerable to neuroinflammation and neurodegeneration. The hippocampus is believed to be the main target of GCs since it has the highest density of GC receptors potentially underlying high sensitivity of hippocampal cells to severe stress. In this review, we analyzed the results of studies on pro- and anti-inflammatory effects of GCs in the hippocampus in different models of stress and stress-related pathologies. The available data form a sophisticated, though often quite phenomenological, picture of a modulatory role of GCs in hippocampal neuroinflammation. Understanding the dual nature of GC-mediated effects as well as causes and mechanisms of switching can provide us with effective approaches and tools to avert hippocampal neuroinflammatory events and as a result to prevent and treat brain diseases, both neurological and psychiatric. In the framework of a mechanistic view, we propose a new hypothesis describing how the anti-inflammatory effects of GCs may transform into the pro-inflammatory ones. According to it, long-term elevation of GC level or preliminary treatment with GC triggers accumulation of FKBP51 protein that suppresses activity of GC receptors and activates pro-inflammatory cascades, which, finally, leads to enhanced neuroinflammation.

An Optoelectronic Device for Remote Measurements of the Geometric Parameters of Sectional Objects

2014 ◽  
Vol 57 (7) ◽  
pp. 765-769 ◽  
Author(s):  
B. V. Skvortsov ◽  
A. N. Malysheva-Stroikova ◽  
I. Yu. Zhiganov
Keyword(s):  
Optoelectronic Device ◽  
Geometric Parameters ◽  
Remote Measurements

Radio Measurements of Coronal Magnetic Fields

1994 ◽  
Vol 144 ◽  
pp. 21-28 ◽  
Author(s):  
G. B. Gelfreikh
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Solar Corona ◽  
Active Regions ◽  
High Sensitivity ◽  
Coronal Magnetic Field ◽  
Transverse Magnetic ◽  
Radio Sources ◽  
Radio Waves ◽  
Solar Active Regions

AbstractA review of methods of measuring magnetic fields in the solar corona using spectral-polarization observations at microwaves with high spatial resolution is presented. The methods are based on the theory of thermal bremsstrahlung, thermal cyclotron emission, propagation of radio waves in quasi-transverse magnetic field and Faraday rotation of the plane of polarization. The most explicit program of measurements of magnetic fields in the atmosphere of solar active regions has been carried out using radio observations performed on the large reflector radio telescope of the Russian Academy of Sciences — RATAN-600. This proved possible due to good wavelength coverage, multichannel spectrographs observations and high sensitivity to polarization of the instrument. Besides direct measurements of the strength of the magnetic fields in some cases the peculiar parameters of radio sources, such as very steep spectra and high brightness temperatures provide some information on a very complicated local structure of the coronal magnetic field. Of special interest are the results found from combined RATAN-600 and large antennas of aperture synthesis (VLA and WSRT), the latter giving more detailed information on twodimensional structure of radio sources. The bulk of the data obtained allows us to investigate themagnetospheresof the solar active regions as the space in the solar corona where the structures and physical processes are controlled both by the photospheric/underphotospheric currents and surrounding “quiet” corona.

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