scholarly journals Застосування ультразвукового пристрою для визначення поверхневої густини текстильної волоконної маси

2021 ◽  
Vol 150 (5) ◽  
pp. 67-73
Author(s):  
В. Г. Здоренко ◽  
С. В. Барилко ◽  
С. М. Лісовець ◽  
Д. О. Шипко
Keyword(s):  
Control Method ◽  
Block Diagram ◽  
Measuring Channel ◽  
Ultrasonic Waves ◽  
Textile Fiber ◽  
Amplitude Control ◽  
Ultrasonic Device ◽  
Accuracy Of Measurements ◽  
Measurement Results

Purpose. Ensuring the determination of the basis weight of the textile fiber mass directly during the manufacturing process using an ultrasonic device equipped with non-contact ultrasonic sensors. In particular, show the effect of the basis weight of a textile fiber mass on the amplitude of probing vibrations in the measuring channel of an ultrasonic device. An amplitude control method is proposed, which is the basis of the operation of the ultrasonic device. It consists in irradiating the textile fiber mass, which moves relative to the scanning bracket with the sensors, and determining the basis weight of the fiber mass by reducing the amplitude of the ultrasonic waves in the measuring channel. The measurement results are processed with their subsequent digitization and computer analysis. It has been established that due to the passage and re-reflection of ultrasonic waves, which fall on two receivers with different vibration delays, it is possible to increase the accuracy of measurements of the average values of the basis weight of the textile fiber mass. Originality. In the general case, it is established that by passing and reflecting ultrasonic waves entering two receivers with different delay of oscillations, it is possible to increase the accuracy of measurements of average values of basis weight of textile fiber mass. The block diagram of the ultrasonic device for determination of basis weight of textile fiber mass is shown and its work is described. The main dependences on which the device system will determine the basis weight of the textile fiber mass are also given.

scholarly journals Application of the Correction Function to Improve the Quality of PM Measurements with Low-Cost Devices

2018 ◽  
Vol 57 ◽  
pp. 02009
Author(s):  
Mariusz Rogulski ◽  
Artur Badyda
Keyword(s):  
Low Cost ◽  
Correction Function ◽  
Reference Measuring ◽  
Comparative Tests ◽  
Measuring Devices ◽  
Reference Device ◽  
Accuracy Of Measurements ◽  
Measurement Results

Reliable information on the particulate matter (PM) concentration in the air is provided by professional, reference measuring devices. In recent times, however, measuring devices using low-cost PM sensors have been gaining more and more popularity. Low-cost PM sensors are not as accurate as professional devices and can under certain circumstances significantly distort results. Therefore comparative measurements with professional devices and the determination of the corrective function are necessary. The article presents the results of tests on the accuracy of measurements made with the use of such sensors after applying a correction function. The form of the correction function was determined based on several months of comparative tests low-cost sensors with reference device. Then, for a different set of low-cost sensors, a correction function was applied and again, during several months of research, the measurement results were compared with a reference device. This made it possible to determine the real measurement uncertainty of this type of equipment, as well as the need to support measurements using earlier comparative tests. Results showed, that for analysed low-cost PM sensors and correction function measurement error was about 15%.

Broadband Microwave Correlator of Noise Signals

2010 ◽  
Vol 17 (2) ◽  
pp. 289-298 ◽  
Author(s):  
Waldemar Susek ◽  
Bronisław Stec
Keyword(s):  
Block Diagram ◽  
Analytical Signal ◽  
Noise Signal ◽  
Precise Determination ◽  
Broadband Noise ◽  
Noise Radar ◽  
Measurement Results ◽  
Narrowband Noise ◽  
Future Plans

Broadband Microwave Correlator of Noise SignalsA real narrowband noise signal representation in the form of an analytical signal in the Hilbert space is presented in the paper. This analytical signal is illustrated in a variable complex plane as a mark with defined amplitude, phase, pulsation and instantaneous frequency. A block diagram of a broadband product detector in a quadrature system is presented. Measurement results of an autocorrelation function of a noise signal are shown and the application of such solution in a noise radar for precise determination of distance changes as well as velocities of these changes are also presented. Conclusions and future plans for applications of the presented detection technique in broadband noise radars bring the paper to an end.

Large-scale Motion of Solar Filaments

2000 ◽  
Vol 179 ◽  
pp. 205-208
Author(s):  
Pavel Ambrož ◽  
Alfred Schroll
Keyword(s):  
Magnetic Flux ◽  
Proper Motion ◽  
Time Scale ◽  
Large Scale ◽  
Accuracy Of Measurements ◽  
Solar Filaments ◽  
General Movement ◽  
Scale Motion ◽  
Velocity Scatter

AbstractPrecise measurements of heliographic position of solar filaments were used for determination of the proper motion of solar filaments on the time-scale of days. The filaments have a tendency to make a shaking or waving of the external structure and to make a general movement of whole filament body, coinciding with the transport of the magnetic flux in the photosphere. The velocity scatter of individual measured points is about one order higher than the accuracy of measurements.

Fast Method for the Determination of Residual Solvents in Radiopharmaceutical Products

2017 ◽  
Vol 68 (4) ◽  
pp. 666-670 ◽  
Author(s):  
Mirela Mihon ◽  
Catalin Stelian Tuta ◽  
Alina Catrinel Ion ◽  
Dana Niculae ◽  
Vasile Lavric
Keyword(s):  
Gas Chromatography ◽  
Control Method ◽  
Limit Of Detection ◽  
The Body ◽  
Biologically Active ◽  
Injection Technique ◽  
Fast Method ◽  
Residual Solvent ◽  
Residual Solvents

The aim of this work was the development and validation of a fast analytical method to determine the residual solvents content in radiopharmaceuticals such as: 18F-Fluorodeoxyglucose (18F-FDG), 18F-Fluoroestradiol (18F-FES), 18F-Fluorothymidine (18F-FLT),18F-Fluoromisonidazole (18F-FMISO). Radiopharmaceuticals are radioactive preparations for medical purposes used in nuclear medicine as tracers in diagnostic imaging and treatment of certain diseases. Positron Emission Tomography (PET) is a medical imaging technique that consists in introducing into the body of a small amount of a biologically active chemical compound labelled with a short lived positron-emitting radioisotope (18F, 11C, 68Ga). Residual solvents are critical impurities in radiopharmaceuticals that can affect labelling, stability and physicochemical properties of drugs. Therefore, the determination of these solvents is essential for quality control of radiopharmaceuticals. Validation of the control method for residual solvents by gas chromatography is referred by the European Pharmacopoeia using a special injection technique (head space). The parameters of the method, which comply with International Conference on Harmonization guidelines, are: accuracy, precision, linearity, limit of detection, limit of quantification and robustness. The proposed method (direct gas chromatography injection) proved to be linear, precise, accurate and robust. Good linearity was achieved for all the solvents and correlation coefficients (R2) for each residual solvent were found more than 0.99.

scholarly journals Development and Validation of a GMP-Compliant High-Pressure Liquid Chromatography Method for the Determination of the Chemical and Radiochemical Purity of [18F]PSMA-1007, a PET Tracer for the Imaging of Prostate Cancer

2021 ◽  
Vol 14 (3) ◽  
pp. 188
Author(s):  
Ines Katzschmann ◽  
Heike Marx ◽  
Klaus Kopka ◽  
Ute Hennrich
Keyword(s):  
Prostate Cancer ◽  
Quality Control ◽  
Radiochemical Purity ◽  
Control Method ◽  
Solid Phase ◽  
Hplc Method ◽  
Attractive Alternative ◽  
Chromatography Method ◽  
Pet Tracer

For the PET imaging of prostate cancer, radiotracers targeting the prostate-specific membrane antigen (PSMA) are nowadays used in clinical practice. [18F]PSMA-1007, a radiopharmaceutical labeled with fluorine-18, has excellent properties for the detection of prostate cancer. Essential for the human use of a radiotracer is its production and quality control under GMP-compliance. For this purpose, all analytical methods have to be validated. [18F]PSMA-1007 is easily radiosynthesized in a one-step procedure and isolated using solid phase extraction (SPE) cartridges followed by formulation of a buffered injection solution and for the determination of its chemical and radiochemical purity a robust, fast and reliable quality control method using radio-HPLC is necessary. After development and optimizations overcoming problems in reproducibility, the here described radio-HPLC method fulfills all acceptance criteria—for e.g., specificity, linearity, and accuracy—and is therefore well suited for the routine quality control of [18F]PSMA-1007 before release of the radiopharmaceutical. Recently a European Pharmacopeia monograph for [18F]PSMA-1007 was published suggesting a different radio-HPLC method for the determination of its chemical and radiochemical purity. Since the here described method has certain advantages, not least of all easier technical implementation, it can be an attractive alternative to the monograph method. The here described method was successfully validated on several radio-HPLC systems in our lab and used for the analysis of more than 60 batches of [18F]PSMA-1007. Using this method, the chemical and radiochemical purity of [18F]PSMA-1007 can routinely be evaluated assuring patient safety.

The Implementation of Permanent Magnet Synchronous Motor Direct Torque Control

2013 ◽  
Vol 712-715 ◽  
pp. 2757-2760
Author(s):  
Jun Li Zhang ◽  
Yu Ren Li ◽  
Long Fei Fu ◽  
Fan Gao
Keyword(s):  
Coordinate System ◽  
Permanent Magnet ◽  
Control Method ◽  
Block Diagram ◽  
Permanent Magnet Synchronous Motor ◽  
Direct Torque Control ◽  
Torque Ripple ◽  
Synchronous Motor ◽  
Torque Control ◽  
Two Phase

In order to deeply understand the characteristics of the permanent magnet synchronous motor direct torque control method, its mathematical models were established in the two-phase stationary coordinate system, the two-phase synchronous rotating coordinate system, and x-y stator synchronous rotating coordinate system. The implementation process of direct torque control method in varied stator winding connection was analyzed in detail. In order to improve the speed and torque performance of the permanent magnet synchronous motor, the direct torque control block diagram and the space voltage vector selection table were given. Finally, the summary and outlook of reducing torque ripple in the permanent magnet synchronous motor direct torque control methods.

Determination of the foaming parameters of polyurethane compositions from the velocity of longitudinal ultrasonic waves

1979 ◽  
Vol 15 (3) ◽  
pp. 316-317 ◽  
Author(s):  
V. M. Mel'nikov ◽  
�. A. Putnin'sh ◽  
V. O. Putninya ◽  
V. P. Karlivan
Keyword(s):  
Ultrasonic Waves ◽  
Longitudinal Ultrasonic Waves
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