Statistical Characteristics of Transmitted Nano-meter Electromagnetic Waves in Random Bio-medical Tissues for X-Ray Diagnostic Images

PIERS Online ◽  
2008 ◽  
Vol 4 (2) ◽  
pp. 161-167
Author(s):  
Yasumitsu Miyazaki
Keyword(s):  
Electromagnetic Waves ◽  
Statistical Characteristics ◽  
X Ray

Entropy estimation of the fragments of chest X-ray images

2021 ◽  
pp. 20-26
Author(s):  
Aleksei Aleksandrovich Rumyantsev ◽  
Farkhad Mansurovich Bikmuratov ◽  
Nikolai Pavlovich Pashin
Keyword(s):  
Neural Network ◽  
Neural Networks ◽  
Binary Classification ◽  
Statistical Characteristics ◽  
Type I ◽  
Deep Convolutional Neural Networks ◽  
Preliminary Calculation ◽  
X Ray ◽  
The Matrix ◽  
Chest X Ray

The subject of this research is medical chest X-ray images. After fundamental pre-processing, the accumulated database of such images can be used for training deep convolutional neural networks that have become one of the most significant innovations in recent years. The trained network carries out preliminary binary classification of the incoming images and serve as an assistant to the radiotherapist. For this purpose, it is necessary to train the neural network to carefully minimize type I and type II errors. Possible approach towards improving the effectiveness of application of neural networks, by the criteria of reducing computational complexity and quality of image classification, is the auxiliary approaches: image pre-processing and preliminary calculation of entropy of the fragments. The article provides the algorithm for X-ray image pre-processing, its fragmentation, and calculation of the entropy of separate fragments. In the course of pre-processing, the region of lungs and spine is selected, which comprises approximately 30-40% of the entire image. Then the image is divided into the matrix of fragments, calculating the entropy of separate fragments in accordance with Shannon’s formula based pm the analysis of individual pixels. Determination of the rate of occurrence of each of the 255 colors allows calculating the total entropy. The use of entropy for detecting pathologies is based on the assumption that its values differ for separate fragments and overall picture of its distribution between the images with the norm and pathologies. The article analyzes the statistical values: standard deviation of error, dispersion. A fully connected neural network is used for determining the patterns in distribution of entropy and its statistical characteristics on various fragments of the chest X-ray image.

Manufacturing Metamaterials Using Synchrotron Lithography

2010 ◽  
Vol 75 ◽  
pp. 230-239
Author(s):  
Herbert O. Moser ◽  
Linke Jian ◽  
Shenbaga M.P. Kalaiselvi ◽  
Selven Virasawmy ◽  
Sivakumar M. Maniam ◽  
...  
Keyword(s):  
Electromagnetic Waves ◽  
Cost Effective ◽  
Pattern Generation ◽  
Geometrical Parameters ◽  
X Ray ◽  
Spectral Bands ◽  
Left Handed ◽  
Aspect Ratios ◽  
Multi Level ◽  
Primary Pattern

The function of metamaterials relies on their resonant response to electromagnetic waves in characteristic spectral bands. To make metamaterials homogeneous, the size of the basic resonant element should be less than 10% of the wavelength. For the THz range up to the visible, structure details of 50 nm to 30 μm are required as are high aspect ratios, tall heights, and large areas. For such specifications, lithography, in particular, synchrotron radiation deep X-ray lithography, is the method of choice. X-ray masks are made via primary pattern generation by means of electron or laser writing. Several different X-ray masks and accurate mask-substrate alignment are necessary for architectures requiring multi-level lithography. Lithography is commonly followed by electroplating of metallic replica. The process can also yield mould inserts for cost-effective manufacture by plastic moulding. We made metamaterials based on rod-split-rings, split-cylinders, S-string bi-layer chips, and S-string meta-foils. Left-handed resonance bands range from 2.4 to 216 THz. Latest is the all-metal self-supported flexible meta-foil with pass-bands of 45% up to 70% transmission at 3.4 to 4.5 THz depending on geometrical parameters.

scholarly journals Revealing the source of Jupiter’s x-ray auroral flares

2021 ◽  
Vol 7 (28) ◽  
pp. eabf0851
Author(s):  
Zhonghua Yao ◽  
William R. Dunn ◽  
Emma E. Woodfield ◽  
George Clark ◽  
Barry H. Mauk ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Heavy Ions ◽  
Electromagnetic Waves ◽  
High Energy ◽  
X Ray ◽  
Planetary Scale ◽  
Ion Cyclotron Waves ◽  
Electromagnetic Ion Cyclotron Waves ◽  
Natural Laboratory

Jupiter’s rapidly rotating, strong magnetic field provides a natural laboratory that is key to understanding the dynamics of high-energy plasmas. Spectacular auroral x-ray flares are diagnostic of the most energetic processes governing magnetospheres but seemingly unique to Jupiter. Since their discovery 40 years ago, the processes that produce Jupiter’s x-ray flares have remained unknown. Here, we report simultaneous in situ satellite and space-based telescope observations that reveal the processes that produce Jupiter’s x-ray flares, showing surprising similarities to terrestrial ion aurora. Planetary-scale electromagnetic waves are observed to modulate electromagnetic ion cyclotron waves, periodically causing heavy ions to precipitate and produce Jupiter’s x-ray pulses. Our findings show that ion aurorae share common mechanisms across planetary systems, despite temporal, spatial, and energetic scales varying by orders of magnitude.

scholarly journals Weak Ferromagnetic Property and Electromagnetic Waves Absorption Characteristic of La(1-x)BaxMnO3

2019 ◽  
Vol 4 (3) ◽  
pp. 96-106
Author(s):  
Engkir Sukirman ◽  
Yosef Sarwanto ◽  
Andon Insani ◽  
Wisnu Ari Adi ◽  
Yose Fachmi Buys
Keyword(s):  
Electromagnetic Waves ◽  
Magnetic Ordering ◽  
Peak Frequency ◽  
High Energy ◽  
Absorption Characteristic ◽  
Network Analyzer ◽  
Ferromagnetic Property ◽  
X Ray ◽  
Neutron Diffractometer ◽  
Weak Ferromagnetic

The weak ferromagnetic property and the electromagnetic waves absorption characteristic of La(1-x)BaxMnO3 (LBMO) compounds have been investigated. The samples of LBMO that are LaMnO3 (S0), La0.9Ba0.1MnO3 (S1); La0.8Ba0.2MnO3 (S2); and La0.7Ba0.3MnO3 (S3) were synthesized using high energy milling (HEM) method. Samples were characterized by means of XRD (X-ray diffractometer), HRPD (high-resolution powder neutron diffractometer), EDS (energy dispersive X-ray spectroscopy, VSM (vibrating sample magnetometer), and VNA (vector network analyzer). There is no magnetic ordering of ferromagnetic in S1 and S2 samples due to the Ba occupation factors of both less than 0.2. The Ba content in the S3 sample is greater than 0.2, hence the ferromagnetic property of the compound is not so visible with the VSM as well as the VNA. The absorption characteristics of electromagnetic waves using VNA indicated that there is an absorption of EM waves in the frequency range between 8-12 GHz with almost the same peak frequency for all four samples at 10.8 GHz with the absorption of around 5 dB. The existence of a weak ferromagnetic property can be detected clearly using HRPD. Neutron diffraction as a probe can observe the magnetic structure accurately even in a material having a weak ferromagnetic property.

scholarly journals Improvement of Sorption Parameters of Nickel Ions on Bentonite in the Result of its Irradiation by Microwaves

2017 ◽  
Vol 18 (4) ◽  
pp. 431-437 ◽  
Author(s):  
L. Sysa ◽  
L. Shevchuk ◽  
A. Kontsur
Keyword(s):  
Electromagnetic Waves ◽  
Adsorption Process ◽  
Sorption Properties ◽  
Nickel Ions ◽  
X Ray ◽  
Langmuir Adsorption ◽  
Argillaceous Material ◽  
Sorption Parameters ◽  
Static Conditions ◽  
Be The Change

The adsorption isotherms of nickel ions from aqueous solutions on bentonite, a natural argillaceous material, previously prepared using ultrahigh-frequency electromagnetic waves ("microwaves") were researched in the article. The phase composition of the sorbent was studied by applying the X-ray powder method. Bentonite sample being pre-wetted and irradiated by microwaves shows 2.7 times better sorption properties than the untreated (native) sample, which was shown on the example of the adsorption process of nickel ions from model solutions in static conditions. The sorption parameters prepared by using the "microwaved" and the native samples of bentonite were calculated according to the Langmuir adsorption equations. The barrier density of nickel in the irradiated sorbent is 16.4 mg/g (0.28 mmol/g), whereas for native bentonite the value of the analogous parameter is 6.0 mg/g (0.10 mmol/g). The reason for such an increase in sorption properties may be the change in the crystalline structure and distribution of micropores on the surface of the sorbent under the action of "microwaves" in the aqueous medium. The determinants in the pre-preparation of sorbent by "microwaves" are the ultimate power and time of irradiation. 

scholarly journals Statistical Characteristics of Solar Proton Flares

1993 ◽  
Vol 141 ◽  
pp. 366-368
Author(s):  
Jia-Long Wang
Keyword(s):  
Magnetic Field ◽  
Solar Flares ◽  
Large Scale ◽  
Solar Physics ◽  
Special Property ◽  
Solar Proton ◽  
Statistical Characteristics ◽  
Earth Orbit ◽  
X Ray ◽  
The Earth

AbstractAn investigation of the statistical behaviour of solar flares responsible for the proton events detected at the earth orbit would be of significance for solar physics and sun-earth research. Based on the data given by Kunches (1992) and other relevant data, we study the statistical behaviour of solar proton flares. The asymmetry of distributions, special property of hard X-ray bursts and relation to the large scale mean magnetic field of the proton flares are given in this paper.

scholarly journals X-ray computed tomography as a method of reconstruction of 3d-characteristics of disseminated sulfides and spinel in plagiodunites from the Yoko-Dovyren intrusion

2019 ◽  
Vol 27 (4) ◽  
pp. 401-419
Author(s):  
D. V. Korost ◽  
A. A. Ariskin ◽  
I. V. Pshenitsyn ◽  
A. N. Khomyak
Keyword(s):  
Computed Tomography ◽  
Morphological Characteristics ◽  
3D Models ◽  
Statistical Characteristics ◽  
Ultramafic Rocks ◽  
Reliable Technique ◽  
X Ray ◽  
Mineral Phases ◽  
Low Concentrations ◽  
X Ray Computed

The paper describes a methodology of applying X-ray computed tomography (CT) in studying textural–morphological characteristics of sulfide-bearing ultramafic rocks from the Yoko-Dovyren layered massif in the northern Baikal area, Buryatia, Russia. The dunites are used to illustrate the applicability of a reliable technique for distinguishing between grains of sulfides and spinel. The technique enables obtaining statistical characteristics of the 3D distribution and size of the mineral phases. The method of 3D reconstructions is demonstrated to be applicable at very low concentrations of sulfides: no than 0.1–0.2 vol %. Differences between 3D models are determined for sulfide segregations of different size, in some instances with features of their orientation suggesting the direction of percolation and accumulation of the sulfide liquids. These data are consistent with the morphology of the largest sulfide segregations, whose concave parts adjoin the surface of the cumulus olivine and simultaneously grow into grains of the poikilitic plagioclase. Detailed information of these features is useful to identify fingerprints of infiltration and concentration of protosulfide liquids in highly crystallized cumulate systems.

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