Subjects -> INSTRUMENTS (Total: 63 journals)
Showing 1 - 16 of 16 Journals sorted alphabetically
Applied Mechanics Reviews     Full-text available via subscription   (Followers: 27)
Computational Visual Media     Open Access   (Followers: 5)
Devices and Methods of Measurements     Open Access  
Documenta & Instrumenta - Documenta et Instrumenta     Open Access  
EPJ Techniques and Instrumentation     Open Access  
European Journal of Remote Sensing     Open Access   (Followers: 18)
Experimental Astronomy     Hybrid Journal   (Followers: 38)
Flow Measurement and Instrumentation     Hybrid Journal   (Followers: 15)
Geoscientific Instrumentation, Methods and Data Systems     Open Access   (Followers: 2)
Geoscientific Instrumentation, Methods and Data Systems Discussions     Open Access   (Followers: 1)
IEEE Journal on Miniaturization for Air and Space Systems     Hybrid Journal   (Followers: 2)
IEEE Sensors Journal     Hybrid Journal   (Followers: 107)
IEEE Sensors Letters     Hybrid Journal   (Followers: 4)
IJEIS (Indonesian Journal of Electronics and Instrumentation Systems)     Open Access   (Followers: 3)
Imaging & Microscopy     Hybrid Journal   (Followers: 7)
InfoTekJar : Jurnal Nasional Informatika dan Teknologi Jaringan     Open Access  
Instrumentation Science & Technology     Hybrid Journal   (Followers: 7)
Instruments and Experimental Techniques     Hybrid Journal   (Followers: 1)
International Journal of Applied Mechanics     Hybrid Journal   (Followers: 8)
International Journal of Instrumentation Science     Open Access   (Followers: 41)
International Journal of Measurement Technologies and Instrumentation Engineering     Full-text available via subscription   (Followers: 1)
International Journal of Metrology and Quality Engineering     Full-text available via subscription   (Followers: 6)
International Journal of Remote Sensing     Hybrid Journal   (Followers: 144)
International Journal of Remote Sensing Applications     Open Access   (Followers: 49)
International Journal of Sensor Networks     Hybrid Journal   (Followers: 2)
International Journal of Testing     Hybrid Journal   (Followers: 1)
Invention Disclosure     Open Access   (Followers: 1)
Journal of Astronomical Instrumentation     Open Access   (Followers: 3)
Journal of Instrumentation     Hybrid Journal   (Followers: 31)
Journal of Instrumentation Technology & Innovations     Full-text available via subscription   (Followers: 2)
Journal of Medical Devices     Full-text available via subscription   (Followers: 4)
Journal of Medical Signals and Sensors     Open Access   (Followers: 1)
Journal of Optical Technology     Full-text available via subscription   (Followers: 4)
Journal of Research of NIST     Open Access   (Followers: 1)
Journal of Sensors and Sensor Systems     Open Access   (Followers: 12)
Journal of Vacuum Science & Technology B     Hybrid Journal   (Followers: 1)
Jurnal Informatika Upgris     Open Access  
Measurement : Sensors     Open Access   (Followers: 5)
Measurement and Control     Open Access   (Followers: 36)
Measurement Instruments for the Social Sciences     Open Access  
Measurement Techniques     Hybrid Journal   (Followers: 3)
Medical Devices & Sensors     Hybrid Journal   (Followers: 1)
Metrology and Instruments / Метрологія та прилади     Open Access  
Metrology and Measurement Systems     Open Access   (Followers: 8)
Microscopy     Hybrid Journal   (Followers: 7)
Modern Instrumentation     Open Access   (Followers: 57)
Optoelectronics, Instrumentation and Data Processing     Hybrid Journal   (Followers: 4)
PFG : Journal of Photogrammetry, Remote Sensing and Geoinformation Science     Hybrid Journal   (Followers: 4)
Photogrammetric Engineering & Remote Sensing     Full-text available via subscription   (Followers: 32)
Remote Sensing     Open Access   (Followers: 57)
Remote Sensing Applications : Society and Environment     Full-text available via subscription   (Followers: 9)
Remote Sensing of Environment     Hybrid Journal   (Followers: 94)
Remote Sensing Science     Open Access   (Followers: 30)
Review of Scientific Instruments     Hybrid Journal   (Followers: 20)
Science of Remote Sensing     Open Access   (Followers: 7)
Sensors International     Open Access   (Followers: 3)
Solid State Nuclear Magnetic Resonance     Hybrid Journal   (Followers: 3)
Standards     Open Access  
Transactions of the Institute of Measurement and Control     Hybrid Journal   (Followers: 12)
Videoscopy     Full-text available via subscription   (Followers: 5)
Труды СПИИРАН     Open Access  
Similar Journals
Journal Cover
Measurement Techniques
Journal Prestige (SJR): 0.163
Number of Followers: 3  
 
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Print) 1573-8906 - ISSN (Online) 0543-1972
Published by Springer-Verlag Homepage  [2469 journals]
  • Combined Method for the Correction of Interval Systems of Linear Algebraic
           Equations

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      Abstract: This article discusses the application of an interval approach in solving problems in the field of physics, particularly spectral analysis. To process data with interval uncertainty, a linear interval tolerance problem is modeled, and the inconsistency (unsolvability) of an interval system of linear algebraic equations (ISLAE) with the use of a recognizing functional is presented. The actual regularization problem of the inconsistent interval systems of linear equations is solved. The idea of a combined method for correcting a linear interval tolerance problem, formulated by S. Shary, is implemented. A new method for controlling the solution of an ISLAE was developed by changing the radii of the matrix elements of the system. The research results can be used, for example, to calculate the concentrations of substances through the measurement of characteristic x-ray radiation.
      PubDate: 2022-05-08
       
  • An Approximate Method for Recovering Input Signals of Measurement
           Transducers

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      Abstract: We consider the problems of information-measuring equipment, modeled by ordinary differential equations, when some physical variable cannot be measured, but its value can be determined by the functional (or operator) of another physical variable available for measurement. Direct application of models with ordinary differential equations for recovering input signals of measurement transducers has not received due development because of the need to calculate (possible high order) derivatives of noisy signals. A method for recovering input signals is proposed, in which the apparatus of hypersingular integrals is used for the approximate calculation of derivatives. We propose approximate methods for calculating derivatives expressed by quadrature formulas for hypersingular integrals. The input signal recovery method has been tested for one accelerometer model. We demonstrate the high effectiveness of the proposed method.
      PubDate: 2022-05-07
       
  • Method for Concurrent Identification of a Linear Dynamic Measurement
           System Based on Preliminary Nonlinear Transformation of the Input Signal

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      Abstract: We consider the problem of the concurrent identification of a linear dynamic measuring system with an unknown input signal under the influence of various destabilizing factors on the system parameters. Solution of this problem will reduce the error of measuring systems in the dynamic measurement mode. To perform the identification, we introduce an additional channel for the transformation of the measured value in the spatial domain; this operator satisfies the condition of non-commutativity with the operator of the system under study. The concurrent identification problem is solved for the linear dynamic characteristic of the main channel of a first-order measuring system. To exclude incorrect operations when differentiating the output signals of a structurally redundant measuring system (SRMS), in the process of concurrent identification the method of modulating functions is used. We present the dependence of the mean square deviations of the reduced input estimation error on the number of measurements during identification for various levels of the standard deviation of the measurement noise, reduced to the input signal scale, as well as on the sampling rate of output signals of a structurally redundant measuring system. The sampling rate determines the size of the observation sample formed during digital processing of the system output signals in a computing device. It is shown that the highest identification accuracy is achieved with a quadratic transformation of the input signal in an additional channel of a structurally redundant measuring system, and the selection of a modest sampling rate of output signals increases the stability of the identification algorithm. In this case, the dependence of the standard deviation of the reduced input estimation error on the sampling rate of the output signals of a structurally redundant measuring system has a minimum. Research results can be used to improve the accuracy of measuring systems in dynamic measurement mode, as well as to enable automatic metrological control of intelligent measuring systems.
      PubDate: 2022-05-05
       
  • An Integrated Methodology for Wavelet Filtering of a Pulse Wave Signal

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      Abstract: The problem of digital filtering of a pulse wave signal relevant in cardiological diagnostics is considered, which is affected by various physiological interferences, such as baseline wander and motion artifacts. A integrated method of wavelet filtering of the pulse wave signal has been developed, which makes it possible to eliminate baseline wander and motion artifacts that distort the shape of the biosignal. The proposed technique is based on multiscale wavelet decomposition of a biosignal in terms of orthogonal Daubechies wavelets. The technique includes sequential procedures for digital processing of the pulse wave: multiscale wavelet transform; modification of the detail coefficients of the wavelet decomposition based on thresholding; reconstruction of the pulse wave signal based on original approximation coefficients and modified detailing coefficients using the inverse wavelet transform. A comparative analysis of the proposed methodology and existing approaches to filtering pulse waves (moving average filtering, median and bandpass filtering) is carried out. To obtain quantitative characteristics of the filtration efficiency assessment, simulation modeling of a pulse wave with noise of various intensity and nature was used. The high quality of pulse wave filtering using the developed technique based on multiscale wavelet transforms can serve as a reliable basis for the development of highly efficient algorithms and hardware and software systems for cardiology diagnostics.
      PubDate: 2022-05-05
       
  • Optimization of the Kernel Probability Density Estimation of a
           Two-Dimensional Random Variable with Independent Components

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      Abstract: The paper studies the problem associated with the optimization of nonparametric probability density estimates, whose relevance is attributed to the lower efficiency of nonparametric algorithms for data processing with the increasing amount of statistical data. In this study, the authors examine a procedure for optimizing the kernel density estimation of a two-dimensional random variable having independent components. The possibility of using the optimal bandwidths of the kernel density estimates of one-dimensional random variables when synthesizing the two-dimensional nonparametric probability density of a random variable having independent components is justified. The proposed approach relies on the asymptotic properties of Rosenblatt–Parzen nonparametric probability density estimation. For a two-dimensional random variable, it is shown that the main contribution to the asymptotic expression for standard deviation is made by the corresponding criteria for one-dimensional random variables. When estimating two-dimensional probability density, it is possible to use bandwidths to minimize the standard deviations of one-dimensional random variables. The obtained conclusions are confirmed by the results of computational experiments in the analysis of normal distribution laws. The possibility of developing the proposed procedure for optimizing the nonparametric probability density estimates of multidimensional random variables having independent components is demonstrated.
      PubDate: 2022-05-04
       
  • Determination of Probabilistic Characteristics of Random Values of
           Estimates of the Lyapunov Function for Description of a Physical Process

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      Abstract: Application of the Lyapunov characteristic function is determined by the means for estimating it. The probabilistic characteristics of estimates of the Lyapunov characteristic function are described for the first time. The probabilistic characteristics of random values of estimates of the Lyapunov function are estimated empirically by statistical methods. A model of a special device for producing estimates of the characteristic function by a direct method is developed in the Matlab package. A quasi-deterministic signal is delivered to the input of the model for which the instantaneous values are distributed according to an arcsine law and at the output a set of values of estimates of the Lyapunov function is obtained which is used to evaluate the probabilistic characteristics of these estimates. Statistical evaluation is carried out by an indirect method. It is found that the values of the estimates of the Lyapunov characteristic function are distributed according to a normal law. The results of these studies will be of use for engineering calculations, e.g., in identifying the errors in transfer of messages in modems with a modulated characteristic function.
      PubDate: 2022-05-02
       
  • Control and Measurement Robot for Determining the Geometric Parameters of
           Large Shells of Revolution: Metrological Analysis

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      Abstract: An important problem for the domestic machine building industry involving the development and introduction of modern means of monitoring the geometric parameters of shells of revolution as basic details of aerospace technology, oil and gas, chemical, and power production equipment is examined. The main methodological and instrumental errors in a design-control and measurement robot for determining the geometric parameters of large-scale shells of revolution which depend on the parameters of the computer vision system are analyzed. A scheme for measuring the geometric parameters of a shell is proposed, the methodological and instrumental errors of the robot and their analytic dependences on the computer vision system are obtained, and ways minimizing these errors are identified. The analytical dependences are used for a metrological analysis of a real prototype computer vision system and the applicability of the chosen robot structure is demonstrated. The relative measurement error is less than 0.3%, which meets the requirements of standards documents.
      PubDate: 2022-05-02
       
  • Calibration Laboratories: Risk Management and the Problem of Assessing
           Opportunities

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      Abstract: An evaluation of resources required for the opportunity management (OM) of calibration laboratories is presented. In this study conducted at the Mendeleev All-Russian Institute for Metrology, a correlation is noted between methods for assessing risks associated with calibration laboratory activities and the topic of opportunity management. It is shown that risk identification methods play an important role in enhancing opportunities to achieve the laboratory’s purpose and objectives. Opportunity management involves the use of new approaches to the allocation of laboratory resources. This work considers OM approaches relying on the Pareto distribution and logistic curves. In addition, the prospects of using hyperbolic distributions in the management of resources required to introduce innovations are noted. It is recommended that risks and innovations be managed taking into account the characteristic parameters of hyperbolic distributions. The consideration of characteristic parameters is aimed at optimally combining frequently performed and new types of work. The novel described approach is shown to support the appropriate selection of solutions for managing opportunities and ensuring the sustainable development of calibration laboratories. This approach is applicable when improving secondary standards and working to higher level standards.
      PubDate: 2022-04-30
       
  • Analytical and Simulation Model of a System for Non-Contact Determination
           of Aircraft Mass and Centre of Gravity

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      Abstract: The problem of increasing the accuracy of determining the mass and centre of gravity of vehicles in order to reduce accidents and improve transportation safety is considered. A comparative analysis of various systems and methods for determining the mass and centre of gravity of vehicles has been carried out. The advantages of non-contact methods and mass measuring instruments have been shown. The technique of non-contact determination of the vehicle mass by the vertical movement of its body has been proposed. An analytical and simulation model of a system for non-contact determination and remote control of the mass and centre of gravity of vehicles has been developed. On the example of aircrafts, the possibilities of simulating this system using various interpolation methods have been considered. For Airbus aircrafts, experiments have been carried out in the MathCad software using linear interpolation, fitting methods, least squares method, and Lagrange polynomials. The principles of constructing a system for non-contact determination of the mass and centre of gravity of aircrafts have been proposed. The choice of methods and instruments for measuring the aircraft fuselage vertical displacement for the implementation of such a system has been substantiated. The research results provide the possibility and prospect of creating a system for non-contact remote control of the mass and centre of gravity of aircrafts, as well as other types of aerial vehicles.
      PubDate: 2022-04-30
       
  • Measurement of the Intensity of a High-Frequency Electric Field:
           Application of a Ring Waveguide with Two Slots Filled with Electro-Optic
           Polymer

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      Abstract: The problem of enhancing the sensitivity of a measurement transducer of high-frequency external electric fields is examined. It is shown that solving this problem is possible by using a ring waveguide with two horizontal or vertical slots filled with an electro-optic polymer. The structure of a measurement transducer of a ring waveguide with two horizontal or vertical slots is examined. In waveguides with two slots, a greater intensity of optical radiation in the region of the slots is achieved, in comparison with waveguides with one slot. The values of the optimal distances between the slots and their width for maximum sensitivity of the measurement transducer are determined. As a result of using the active organic compound SEO125 and waveguides with two slots, the transducer under study makes it possible to measure the strength of alternating electric fields of frequency 0–10 GHz over the range 150–16·106 V/m with resolution up to 150 V/m. The measurement transducer can be used to detect high frequency waves and electromagnetic pulses, as well as to analyze external electromagnetic interference and diagnose high frequency electronic circuits.
      PubDate: 2022-04-30
       
  • Method for Measuring a Surface Profile Using a Mechatronic Profiler with
           Parallel Control of Sensor Drives

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      Abstract: Issues associated with improving the maneuverability and operating speed of a mechatronic profiler, as well as extending the profile measurement range for various surfaces, are considered. In order to solve these problems, a method was proposed for measuring a surface profile along a given trajectory using a mechatronic profiler that provides parallel control of sensor drives. A system for controlling a mechatronic profiler characterized by distributed control of drives is described, effectively implementing the programmed movements of the profiler’s laser sensor. The described control system improves the accuracy, sensitivity, speed, and reliability of the mechatronic profiler during operation, as well as reducing measurement and calibration time while significantly increasing the accuracy of measurement results. In addition, a developed information and measurement system of the mechatronic profiler is presented, along with a specification of software for controlling the electric drives of a mechatronic profiler. The following metrological characteristics of the mechatronic profiler were established and confirmed during verification: range of measuring the sensor-to-surface distance – 100–500 mm; maximum permissible absolute measurement error – ±0.05% of the range; circumferential measurement range – 0–360°; maximum permissible error of the rotary encoder ±30″. The results of surface profile measurements performed in polar coordinates for a corrugated sheet having a downward deflection amounting to 13.8 ± 0.05 mm in the cross-section are presented in graphic form. The study results can be used in various economic sectors: mechanical engineering, agriculture, construction, etc.
      PubDate: 2022-04-30
       
  • Enthalpy Calibration Method for Differential Scanning Calorimeters

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      Abstract: A method for enthalpy calibration of differential scanning calorimeters is described which makes it possible to eliminate the existing limits on the temperature range within which this metrological procedure can be carried out. The proposed method does not require use of standard samples of heats of fusion, so it is not limited by the thermal properties of certified materials. This method solves the problem of increasing the accuracy of measurements of specific enthalpy and heats of phase transitions of various substances for all types of differential scanning calorimeters. The effectiveness of the proposed method for solving the accuracy problems is confirmed and illustrated by the authors by comparing the results of measurements of heats of fusion of a number of metals. Results of measurements obtained on differential scanning calorimeters calibrated by the proposed method and on the same instruments, but calibrated in accordance with the generally accepted standard method of the International Union of Pure and Applied Chemistry, are compared. During the experiment, the advantages of the enthalpy calibration method developed here are identified in terms of saving the time and the costs necessary for calibration. The results can be used in work with differential scanning calorimeters, in the development of new materials, the monitoring of technological processes, production, input, and output control, as well as in the development of methods for studying various materials using differential scanning calorimeters.
      PubDate: 2022-04-30
       
  • A Technique for the Selection of the Guard Band in Climatic Tests of
           Radio-Electronic Equipment

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      Abstract: The problem of estimating the correspondence between the quality of a technical product and specified requirements in climatic testing is described. The problem of estimating false acceptances and false rejections, which are risks that arise in climatic testing of radio-electronic equipment, is considered. It is shown that additional misalignment of the transmitting lines of radio-electric equipment caused by temperature irregularities tends to increase these risks. A technique of selecting the guard band in order to minimize the probability of false acceptance and false rejection of devices that are being tested is proposed. Based on the results obtained it becomes possible to determine the optimal coefficient of the guard band of the measurements that minimizes the risks to the consumer and producer of radio-electronic equipment.
      PubDate: 2022-04-30
       
  • Electromagnetic System for Embodying the Unit of Mass

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      Abstract: Results of theoretical and experimental studies of the magnetic characteristics of the electromagnetic system of a prototype of the Kibble balance are presented. Based on the prototype, the technical solutions that can be used to create a primary standard of a kilogram from fundamental physical constants are examined. The finite element method for calculating the geometrical shapes and sizes of the components of the system is used, for the purpose of deriving the constant value of the conversion coefficient of BL along the system axis. The electromagnetic system is designed and manufactured from the results of the calculations. The equipment, designed for measurement of the topology of the magnetic field in the gap of the magnetic system, was developed based on the National Primary Standard of units of power of magnetic losses and the magnetic flux density of a permanent magnetic field over the range from 0.1 to 2.5 T and magnetic flux over the range from 1·10–5 to 3·10–2 Wb, GET 198-2017. Experimental studies of the distribution of magnetic flux density in the gap of an electromagnetic system and outside of this system were conducted. The power characteristics of the electromagnetic system were determined. The effect of an electric current flowing past, on a coil in weighting mode, on the change of magnetic linkage of the coil is recorded. The condition of a coil in weighting mode in which the conversion coefficient of the magnetic system does not depend on the electric current intensity in the coil was determined.
      PubDate: 2022-04-30
       
  • Transmission of Signals of Promising Hydrogen Frequency and Time Standards
           Via Fiber-Optic Channel with Phase Instability Compensation

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      Abstract: Methods for improving the accuracy of reference frequency and time signals transmission using a new fiber-optic modem with phase instability compensation are presented. Algorithms for transmitting a 1PPS pulse time signal with a synchronization error of no more than 200 ps are considered. The results of measurements of the Allan deviation during the transmission of a reference signal with a frequency of 100 MHz through a two-kilometer fiber-optic line with additional external temperature impact are presented. With the help of the developed fiber-optic line emulator, the accuracy of reference signals transmission for fiber lines up to 100 km long, as well as for various external impacts, has been estimated. A full-function device for transmitting and receiving reference frequency and time signals through a fiber-optic communication line up to 100 km long, the instability characteristics of which reach approximately 1–3·10–17 in the daily measurement interval, has been developed.
      PubDate: 2022-04-30
       
  • Method for Automatic Online Updating of Personal Biometric Data Based on
           Speech Signal of the Biometric System User

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      Abstract: The article considers the problem of personal biometric data “aging” over time. A method has been proposed to overcome this problem by automatically updating the specified data in the biometric system storage using the speech signals of registered users obtained during latest requests for their identification and online service. The proposed method uses a scale-invariant indicator of the voice template quality. As a result, it is characterized by guaranteed reliability of the decisions made in the conditions of a wide speech signal dynamic range. It was established that the use of a scale-invariant indicator provides the guaranteed significance level of decisions made by a conventional observer. A full-scale experiment implementing the proposed method has been set up and carried out using an authoring software; practical justification for the effectiveness of the proposed method with real speech data has been given. The results obtained are intended for using in the development of new and modernization of existing systems and technologies for automated quality control and updating of personal biometric data.
      PubDate: 2022-04-04
       
  • Coolant Flow Rate Measurement Technique for Nuclear Power Reactor Control
           Systems

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      Abstract: The problem of ensuring an error of no more than 1% in monitoring the coolant flow rate in the piping of the first loop of the reactor in nuclear power plants is examined. A method for measuring the coolant flow rate based on recording the γ-radiation during the variation of the oxygen activity of the coolant is proposed. A measurement device is created for recording bursts of γ-radiation which contain probes based on fiber optics and ways of placing it on the piping are described. To implement the proposed method, an optical flowmeter has been developed for monitoring the coolant flow in laminar and turbulent flow regimes at different temperatures. An optimum doping for the core of the fiber optic with germanium oxide is established for measurements of the coolant flow rate for different intensities of the oxygen activity. A method is proposed for recovery of the transmission of the optical fiber in measurements of the coolant flow rate in the presence of γ-radiation. A technique for measuring the coolant flow rate is examined in detail and features of its implementation are noted. Results from a study of the optical flowmeter on a test stand are presented.
      PubDate: 2022-04-01
       
  • Technique for Assessing the Reproduction Error of the Complex Reflection
           Coefficient Unit in Waveguides

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      Abstract: A technique for determining the standard deviation and non-excluded systematic error in reproducing the complex reflection coefficient unit in waveguides has been proposed and a corresponding technique has been developed. It has been established that the reproduction error depends on the value of the measured complex reflection coefficient for a specific frequency, and its dominant component is due to the error in measuring the depth of short-circuit references. It is advisable to use the obtained results of determining the reproduction error in the form of tables in order to assess the error in the measurement results of the complex reflection coefficient. The proposed technique can be used to determine the accuracy indicators of measurements of the complex reflection coefficient when creating the State Primary Standard for the complex reflection coefficient unit in standardized waveguides at frequencies up to 178.4 GHz.
      PubDate: 2022-03-31
       
  • NMR Spectra of Cesium in Aqueous Solutions. Determination of the Magnetic
           Moment of Cesium-133 Nucleus

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      Abstract: The paper considers the issue of accuracy improvement in determining the magnetic moment of the cesium-133 nucleus used as a reference for evaluating the magnetic properties of short-lived cesium isotopes. In the study, the resonant frequency ratios of water protons to cesium-133 nuclei were experimentally obtained for the aqueous solutions of CsF, CsCl, and CsNO3 at concentrations of 0.1–0.4 mol/kg H2O. The simultaneous detection of nuclear magnetic resonance signals from water protons and cesium-133 nuclei was shown to minimize random and systematic uncertainties in determining the resonant frequency ratio between water protons and cesium to eight decimal places. In addition, the cesium salt content in water was extrapolated to zero concentrations. For single cesium ions in water, the ratio of resonant frequencies reached 7.6241815(2). The magnetic moment of the cesium-133 nucleus, amounting to 2.58243(12), was calculated taking into account data on the proton magnetic moment, as well as the shielding of protons and cesium ions in water, to be compared with the data of other authors. The studied aqueous solutions of cesium salts revealed an extremely high dependence between the resonant frequency of cesium nuclei and the solution temperature, which is 12 times higher than a similar dependence of water proton resonant frequency.
      PubDate: 2022-03-31
       
  • Miniature Image-Converter Cameras for Measurement of the Temporal
           Characteristics of Optical Pulses in Nano- And Picosecond Ranges

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      Abstract: The task of studying the temporal structure of optical pulses in the nano- and picosecond ranges, and measurements of the temporal characteristics of the pulses, was undertaken. In order to resolve this task, measurement instruments for the temporal characteristics of optical pulses were created: miniature image-converter streak cameras with picosecond temporal resolution. The functional capabilities and examples of use of the specified cameras are described. Their principle of operation, design, characteristics, and functions are examined. The manufacturing process of the time-analysis image-converter streak tubes for these cameras, performed in a unique high-vacuum manufacturing site, is described. The functional capabilities of the software to control the image acquisition process, as well as for processing and analysis of the images captured by the image-converter streak cameras, are studied. The metrological and chief technical characteristics of the miniature image-converter streak cameras are presented. With the use of the miniature picosecond image-converter streak camera, the temporal structure of the radiation of a semi-conductor pulsed laser was studied, the pulse form was determined and their duration was measured, with an estimation of the measurement error. It is shown that miniature picosecond image-converter streak cameras are an effective instrument for controlling the parameters of the radiation of nano- and picosecond pulsed lasers in the course of their development, adjustment, tests, and application. Information on the actual temporal form of the laser pulses, obtained by the image-converter streak cameras, is of great value for developers of pulsed lasers, as well as for specialists in the fields of laser distance measurement and spectroscopy.
      PubDate: 2022-03-30
       
 
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