Rapid measuring system for contrast thresholds

1984 ◽  
Vol 55 (7) ◽  
pp. 1061-1063 ◽  
Author(s):  
H. Horvath
Keyword(s):  
Measuring System ◽  
Contrast Thresholds

High-voltage monitoring by the fiber-optic recirculating measuring system

2020 ◽  
pp. 38-44
Author(s):  
A. V. Polyakov ◽  
M. A. Ksenofontov
Keyword(s):  
Optical Fibers ◽  
High Voltage ◽  
Optical Sensors ◽  
Electromagnetic Interference ◽  
Fiber Optic ◽  
Electric Power Industry ◽  
Measuring System ◽  
Voltage Range ◽  
External Electromagnetic Fields ◽  
Optic Communication

Optical technologies for measuring electrical quantities attract great attention due to their unique properties and significant advantages over other technologies used in high-voltage electric power industry: the use of optical fibers ensures high stability of measuring equipment to electromagnetic interference and galvanic isolation of high-voltage sensors; external electromagnetic fields do not influence the data transmitted from optical sensors via fiber-optic communication lines; problems associated with ground loops are eliminated, there are no side electromagnetic radiation and crosstalk between the channels. The structure and operation principle of a quasi-distributed fiber-optic high-voltage monitoring system is presented. The sensitive element is a combination of a piezo-ceramic tube with an optical fiber wound around it. The device uses reverse transverse piezoelectric effect. The measurement principle is based on recording the change in the recirculation frequency under the applied voltage influence. When the measuring sections are arranged in ascending order of the measured effective voltages relative to the receiving-transmitting unit, a relative resolution of 0,3–0,45 % is achieved for the PZT-5H and 0,8–1,2 % for the PZT-4 in the voltage range 20–150 kV.

Information and measuring system based on the device «Polyreotest PRT-2» for wheat hardness control

2020 ◽  
Vol 29 (8) ◽  
pp. 57-61
Author(s):  
V.Y. Chernykh ◽  
◽  
E.V. Karpushina ◽  
N. Yu. Bykova ◽  
A.S. Maksimov ◽  
...  
Keyword(s):  
Measuring System

A new method of fluxgate signal extraction

2017 ◽  
Vol 2017 (45) ◽  
pp. 83-89
Author(s):  
A.A. Marusenkov ◽  
Keyword(s):  
High Frequency ◽  
Second Harmonic ◽  
Excitation Frequency ◽  
Low Noise ◽  
Measuring System ◽  
Signal Extraction ◽  
Fluxgate Magnetometer ◽  
New Approach ◽  
Average Value ◽  
The Time Domain

Using dedicated high-frequency measuring system the distribution of the Barkhausen jumps intensity along a reversal magnetization cycle was investigated for low noise fluxgate sensors of various core shapes. It is shown that Barkhausen (reversal magnetization) noise intensity is strongly inhomogeneous during an excitation cycle. In the traditional second harmonic fluxgate magnetometers the signals are extracted in the frequency domain, as a result, some average value of reversal magnetization noises is contributed to the output signals. In order to fit better the noise shape and minimize its transfer to the magnetometer output the new approach for demodulating signals of these sensors is proposed. The new demodulating method is based on information extraction in the time domain taking into account the statistical properties of cyclic reversal magnetization noises. This approach yields considerable reduction of the fluxgate magnetometer noise in comparison with demodulation of the signal filtered at the second harmonic of the excitation frequency.

MEASURING SYSTEM FOR MONITORING GRAIN TEMPERATURE DURING STORAGE

2020 ◽  
Author(s):  
S.А. Zelensky ◽  
◽  
M.S Stepanov ◽  
Keyword(s):  
Nondestructive Testing ◽  
Thermophysical Properties ◽  
Science And Technology ◽  
Measuring System ◽  
Grain Temperature

In science and technology, today various sensors of electrical and non-electrical quantities are used. The article provides a brief overview of the primary converters. One of the devices for nondestructive testing of thermophysical properties for determining the characteristics of agricultural objects in production is presented.

Compact Energy Measuring System for Short Pulse Lasers

2013 ◽  
Vol 20 (2) ◽  
pp. 183-190 ◽  
Author(s):  
A. Barna ◽  
I. B. Földes ◽  
Z. Gingl ◽  
R. Mingesz
Keyword(s):  
Short Pulse ◽  
Electronic Devices ◽  
Laser Pulses ◽  
Measuring System ◽  
Electric Response ◽  
Usb Interface ◽  
Radiated Noise ◽  
Fiber Optical ◽  
Measurement Control ◽  
Short Pulse Lasers

Abstract In experiments with short-pulse lasers the measurement control of the energy of the laser pulse is of crucial importance. Generally it is difficult to measure the amplitude of the pulses of short-pulse lasers using electronic devices, their response time being longer than the duration of the laser pulses. The electric response of the detector is still too fast to be directly digitized therefore a peak-hold unit can be used to allow data processing for the computer. In this paper we present a device which measures the energy of UV short (fs) pulses shot-byshot, digitizes and sends the data to the PC across an USB interface. The circuit is based on an analog peak detect and hold unit and the use of fiber optical coupling between the PC and the device provides a significant improvement to eliminate potential ground loops and to reduce conductive and radiated noise as well. The full development is open source and has been made available to download from our web page (http://www.noise.inf.u-szeged.hu/Instruments/PeakHold/).

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