scholarly journals NPVO Refractometer for diffusing substance investigations

2017 ◽  
Vol 2 (5) ◽  
pp. 44-48 ◽  
Author(s):  
Мария Якимова ◽  
Mariya Yakimova ◽  
Валентин Алехнович ◽  
Valentin Alekhnovich ◽  
Александр Григорьянц ◽  
...  
Keyword(s):  
Standing Wave ◽  
Measurement Results ◽  
Improve Accuracy

The paper deals with the use of refractometry for the analysis of strongly scattering materials. The peculiarities in the interpretation of measurement results, and in particular, the simulation of attenuation factors of a flat and damped wave for the use in the equation of coupling are considered. Besides, there is investigated a degree of the influence of different parameters (concentration of particles and their parameters) upon results of experiments which will improve accuracy and reliability of experiments. The results of experiments are obtained with the aid of NPVO refractometer on strongly scattering samples with a calibrated composition. The processing of experiment results carried out with the use of Mi scattering factors and scattering factors of standing wave allows estimating in what cases it makes sense to use more complex expressions for a damped wave and in what cases may be used Mi factors.

Research on Precision Measuring System for Motor Speed

2012 ◽  
Vol 588-589 ◽  
pp. 1103-1107
Author(s):  
Yu Hai Gu ◽  
Qiu Shi Han ◽  
Xiao Li Xu ◽  
Hai Tao Zhang
Keyword(s):  
Control Systems ◽  
Precise Measurement ◽  
Serial Communication ◽  
Measuring System ◽  
Motor Speed ◽  
Precision Measuring ◽  
Measurement Results ◽  
Improve Accuracy ◽  
Improving Accuracy ◽  
Motor Control Systems

In order to improve accuracy of measuring motor speed in precision motor control systems, a method of precise measurement of speed with CPLD is proposed, which measures the truncated parts of the measured pulse on the basis of measuring raster count pulse within the equal period, and takes them as compensation, thus improving accuracy of measuring the raster pulse. In this paper, a speed measuring formula is given. Measuring system is provided with parallel and serial communication interfaces for output of measurement results.

scholarly journals The specifics of quasi-optical measurements in the submillimetre waveband

2021 ◽  
pp. 21-27
Author(s):  
G. V. Kozlov ◽  
S. P. Lebedev
Keyword(s):  
Electromagnetic Field ◽  
Optical Waveguide ◽  
Standing Wave ◽  
Wave Structure ◽  
Dielectric Measurement ◽  
Optical Measurements ◽  
Measurement Results

The paper investigates the influence of the electromagnetic field and standing wave structure in a quasi-optical waveguide on the dielectric measurement results and gives recommendations on the layout of measuring circuits.

Design of a compact wide band microstrip antenna with very low VSWR for WiMAX applications

2016 ◽  
Vol 9 (3) ◽  
pp. 685-690 ◽  
Author(s):  
Aparna Kundu ◽  
Ujjal Chakraborty ◽  
Anup Kumar Bhattacharjee
Keyword(s):  
Standing Wave ◽  
Microstrip Antenna ◽  
Low Voltage ◽  
Single Layer ◽  
Wide Band ◽  
Center Frequency ◽  
Computational Results ◽  
Measurement Results ◽  
Rectangular Microstrip Antenna ◽  
Peak Gain

A single-layer coaxial-fed compact rectangular microstrip antenna with very low voltage standing wave ratio (VSWR) is presented in this paper. The simulated VSWR of the proposed antenna 1.00374 is obtained near the center frequency of the operating band (3.5 GHz). Simulation and measurement results indicate that the bandwidth (simulated: 3.36–3.715 GHz, and measured: 3.295–3.645 GHz) of the antenna exceeds 10% below VSWR 2, when the size reduction of the antenna is about 81.6%. The realized peak gain is obtained about 2.15 dBi at 3.5 GHz. For the verification of the computational results, two designs were fabricated and measured. Good agreements between simulated and measured results were found.

scholarly journals Microwave Absorption by Used Moulding and Core Sands

2012 ◽  
Vol 12 (3) ◽  
pp. 87-90
Author(s):  
D. Nowak ◽  
M. Stachowicz ◽  
K. Granat ◽  
M. Pigiel
Keyword(s):  
Microwave Absorption ◽  
Standing Wave ◽  
Slot Line ◽  
Measurement Results ◽  
Absorption Measurements

Abstract The paper presents measurement results of standing wave ratio to be used as an efficiency indicator of microwave absorption by used moulding and core sands chosen for the microwave utilization process. The absorption measurements were made using a prototype stand of microwave slot line. Examined were five used moulding and core sands. It was demonstrated that the microwave absorption measurements can make grounds for actual microwave utilization of moulding and core sands.

Hyperspectral image classification using wavelet transform-based smooth ordering

2019 ◽  
Vol 17 (06) ◽  
pp. 1950050 ◽  
Author(s):  
Lina Yang ◽  
Hailong Su ◽  
Cheng Zhong ◽  
Zuqiang Meng ◽  
Huiwu Luo ◽  
...  
Keyword(s):  
Wavelet Transform ◽  
Spatial Information ◽  
Hyperspectral Image ◽  
Interpolation Method ◽  
Computational Cost ◽  
Classification Performance ◽  
Hyperspectral Image Classification ◽  
Measurement Results ◽  
Improve Accuracy ◽  
Main Components

To efficiently improve the accuracy of hyperspectral image (HSI) classification, the spatial information is usually fused with spectral information so that the classification performance can be enhanced. In this paper, we propose a new classification method called wavelet transform-based smooth ordering (WTSO). WTSO consists of three main components: wavelet transform for feature extraction, spectral–spatial based similarity measurement, smooth ordering based 1D embedding, and construction of final classifier using interpolation scheme. Specifically, wavelet transform is first imposed to decompose the HSI signal into approximate coefficients (ACs) and details coefficients (DCs). Then, to measure the similar level of pairwise samples, a novel metric is defined on the ACs, where the spatial information serves as the prior knowledge. Next, according to the measurement results, smooth ordering is applied so that the samples are aligned in a 1D space (called 1D embedding). Finally, since the reordering samples are smooth, the labels of test samples can be recovered using the simple 1D interpolation method. In the last step, in order to reduce the bias and improve accuracy, the final classifier is constructed using multiple 1D embeddings. The use of wavelet transform in WTSO can also reduce the high dimensionality of HSI data. By converting the hight-dimensional samples into a 1D ordering sequence, WTSO can reduce the computational cost, and simultaneously perform classification for the test samples. Note that in WTSO, the smooth ordering based 1D embedding and interpolation are executed in an iterative manner. And they will be terminated after finite steps. The proposed method is experimentally demonstrated on two real HSI datasets: IndianPines and University of Pavia, achieving promising results.

Scanning Type Microprobe for Displacement Measurement Based on Standing Wave Detection Using an Optically Trapped Particle

2011 ◽  
Vol 5 (3) ◽  
pp. 395-402 ◽  
Author(s):  
Yasuhiro Takaya ◽  
◽  
Masaki Michihata ◽  
Terutake Hayashi
Keyword(s):  
Standing Wave ◽  
Three Dimensional ◽  
Wave Pattern ◽  
Displacement Sensor ◽  
Wafer Surface ◽  
Spherical Lens ◽  
Measurement Results ◽  
Three Dimensional Measurement ◽  
Measurement Principle ◽  
Optically Trapped

The new scanning type microprobe, based on a standing wave pattern as the interferometric scale and an optically trapped microprobe as the sensing probe to read the scale, is proposed. To confirm the measurement principle the fundamental investigation was conducted experimentally and the properties such as the accuracy, the resolution and the measurable range are evaluated. The feasibility as amicro-displacement sensor is indicated by measurement results of a silicon wafer surface and a silicon sphere. In order to investigate the ability of three-dimensional measurement the scanning measurement of a micro spherical lens with a diameter of 2 mm is carried out.

Eels Under Standing Wave Conditions

1982 ◽  
Vol 40 ◽  
pp. 492-495
Author(s):  
O.L. Krivanek ◽  
J. TaftØ
Keyword(s):  
Standing Wave ◽  
Wave Conditions ◽  
Set Up ◽  
A Site ◽  
Complex Crystal

It is well known that a standing electron wavefield can be set up in a crystal such that its intensity peaks at the atomic sites or between the sites or in the case of more complex crystal, at one or another type of a site. The effect is usually referred to as channelling but this term is not entirely appropriate; by analogy with the more established particle channelling, electrons would have to be described as channelling either through the channels or through the channel walls, depending on the diffraction conditions.

Voltage and Orientation Dependence of Characteristic X-Ray Production in Thin Crystals

1985 ◽  
Vol 43 ◽  
pp. 414-415
Author(s):  
G. Thomas ◽  
K. M. Krishnan ◽  
Y. Yokota ◽  
H. Hashimoto
Keyword(s):  
Standing Wave ◽  
Incident Beam ◽  
Orientation Dependence ◽  
Incident Plane Wave ◽  
Crystalline Materials ◽  
X Ray ◽  
Incident Plane ◽  
Crystal Unit Cell ◽  
Beam Orientation ◽  
Acceleration Voltage

For crystalline materials, an incident plane wave of electrons under conditions of strong dynamical scattering sets up a standing wave within the crystal. The intensity modulations of this standing wave within the crystal unit cell are a function of the incident beam orientation and the acceleration voltage. As the scattering events (such as inner shell excitations) that lead to characteristic x-ray production are highly localized, the x-ray intensities in turn, are strongly determined by the orientation and the acceleration voltage. For a given acceleration voltage or wavelength of the incident wave, it has been shown that this orientation dependence of the characteristic x-ray emission, termed the “Borrmann effect”, can also be used as a probe for determining specific site occupations of elemental additions in single crystals.

3-D optical transfer in excitation field synthesis microscopes

1995 ◽  
Vol 53 ◽  
pp. 64-65
Author(s):  
Vijay Krishnamurthi ◽  
Brent Bailey ◽  
Frederick Lanni
Keyword(s):  
Standing Wave ◽  
Spatial Information ◽  
3D Structure ◽  
Complete Recovery ◽  
Weighting Factor ◽  
Optical Transfer Function ◽  
Excitation Field ◽  
Optical Transfer ◽  
Set Up ◽  
Focus Plane

Excitation field synthesis (EFS) refers to the use of an interference optical system in a direct-imaging microscope to improve 3D resolution by axially-selective excitation of fluorescence within a specimen. The excitation field can be thought of as a weighting factor for the point-spread function (PSF) of the microscope, so that the optical transfer function (OTF) gets expanded by convolution with the Fourier transform of the field intensity. The simplest EFS system is the standing-wave fluorescence microscope, in which an axially-periodic excitation field is set up through the specimen by interference of a pair of collimated, coherent, s-polarized beams that enter the specimen from opposite sides at matching angles. In this case, spatial information about the object is recovered in the central OTF passband, plus two symmetric, axially-shifted sidebands. Gaps between these bands represent "lost" information about the 3D structure of the object. Because the sideband shift is equal to the spatial frequency of the standing-wave (SW) field, more complete recovery of information is possible by superposition of fields having different periods. When all of the fields have an antinode at a common plane (set to be coincident with the in-focus plane), the "synthesized" field is peaked in a narrow infocus zone.

Standing wave diffraction with a beam of slow atoms

1997 ◽  
Vol 44 (10) ◽  
pp. 1863-1882 ◽  
Author(s):  
S. KUNZE , S. DURR, K. DIECKMANN , M.
Keyword(s):  
Standing Wave ◽  
Wave Diffraction
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