bluuebunny/crossref_metadata_2025 huggingface dataset:
Pattern recognition for EMG based forearm orientation and contraction in myoelectric prosthetic hand
Authors: Suganthi J. Roselin , Rajeswari K.
Published: January 2024

Communication is an essential component of human nature. It connects humans, allowing them to learn, grow, col-laborate, and resolve conflicts. Several aspects of human society, relationships, and growth would be significantly hampered in the absence of efficient communication. Hand gesture recognition is a way to interact with technology that can be particularly useful for individuals with disabilities. This hand gesture recognition is mainly employed in sign language translation, healthcare, rehabilitation, prosthesis, and Human-Computer Interaction (HCI). The high degree of dexterity is a main challenge for prosthetic limbs. In order to meet this challenge, hand gesture recognition is employed for the prosthetic limb, which can be used for rehabilitation. The objective of this article is to show the methodology for the recognition of hand gestures using Electromyography (EMG) signals. This article uses the pro-posed time domain feature extraction method called Absolute Fluctuation Analysis (AFA) along with the Root Mean Square (RMS) for the feature extraction method. Along with these feature extraction methods, repeated stratified K-fold cross validation is used for the validation of the classifiers such as the XGB classifier, the K-Nearest Neighbour (KNN) classifier, the Decision Tree classifier, the Random Forest classifier, and the SVM classifier, whose mean recognition accuracy is given by 93.26%, 87.42%, 85.26%, 92.23%, and 91.78%, respectively. The recognition accuracy of machine learning classifiers is being compared with state-of-the-art networks such as artificial neural net-works (ANN), long short-term memory (LSTM), bidirectional LSTM, gated recurrent units (GRU), and convolution-al neural networks (CNN), which provide recognition accuracy of 96.65%, 99.16%, 99.94%, and 99.99%, respectively.
A novel data-driven integrated detection method for network intrusion classification based on multi-feature imbalanced data
Authors: Wang Chia-Hung , Ye Qing , Cai Jiongbiao , Suo Yifan , Lin Shengming , Yuan Jinchen , Wu Xiaojing
Published: January 2024

The multi-feature and imbalanced nature of network data has always been a challenge to be overcome in the field of network intrusion detection. The redundant features in data could reduce the overall quality of network data and the accuracy of detection models, because imbalance could lead to a decrease in the detection rate for minority classes. To improve the detection accuracy for imbalanced intrusion data, we develop a data-driven integrated detection method, which utilizes Recursive Feature Elimination (RFE) for feature selection, and screens out features that are conducive to model recognition for improving the overall quality of data analysis. In this work, we also apply the Adaptive Synthetic Sampling (ADASYN) method to generate the input data close to the original dataset, which aims to eliminate the data imbalance in the studied intrusion detection model. Besides, a novel VGG-ResNet classification algorithm is also proposed via integrating the convolutional block with the output feature map size of 128 from the Visual Geometry Group 16 (VGG16) of the deep learning algorithm and the residual block with output feature map size of 256 from the Residual Network 18 (ResNet18). Based on the numerical results conducted on the well-known NSL-KDD dataset and UNSW-NB15 dataset, it illustrates that our method can achieve the accuracy rates of 86.31% and 82.56% in those two test datasets, respectively. Moreover, it can be found that the present algorithm can achieve a better accuracy and performance in the experiments of comparing our method with several existing algorithms proposed in the recent three years.
RETRACTED: Fuzzy decision-making in tourism and hospitality: A bibliometric review
Authors: Qin Yong , Xu Zeshui , Wang Xinxin , Škare Marinko
Published: January 2024

This article has been retracted. A retraction notice can be found at https://doi.org/10.3233/JIFS-219433.
A relational extraction approach based on multiple embedding representations and multi-head self-attention
Authors: Qin Zhi , Liu Enyang , Zhang Shibin , Chang Yan , Yan Lili
Published: January 2024

Currently, word segmentation errors and polysemy problems are common in the field of Chinese relationship extraction. Although character-based model input can avoid word segmentation errors, in order to obtain the word information of a sentence, it is often necessary to introduce a dictionary or an external knowledge base to expand the word information, which requires a lot of manpower and time. In response to the above existing problems, this article uses characters as input, uses multiple embedding models to jointly form a character vector sequence, and obtains features containing character information through BiLSTM and attention layers; considering that convolutional neural networks are good at extracting local features, obtain features containing word information through multi-kernel convolutional layers and multi-head self-attention layers, and finally use a gating mechanism to fuse the features. The model was tested on the public SanWen data set and our own cultural-travel data set, and obtained F1 values of 61.22% and 60.26% respectively. Experimental results show that our method can achieve better relationship extraction effects without using word segmentation tools and without building a dictionary or external knowledge base, and the effect is better than most commonly used models currently.
Effect of acupuncture combined with lower limb gait rehabilitation robot on improving walking function in stroke patients with hemiplegia
Authors: Hu Chuan , Wang Xin , Pan Tongliang
Published: January 2024

BACKGROUND: No study has yet demonstrated the effect of lower limb gait rehabilitation robot treatment combined with acupuncture on stroke patients. OBJECTIVE: To explore the effect of acupuncture combined with lower limb gait rehabilitation robot on walking function in patients with hemiplegia after stroke. METHODS: Fifty-six patients with hemiplegia after stroke were enrolled and randomly divided into two groups. The control group received regular rehabilitation training and acupuncture therapy; the intervention group was additionally trained by AiWalker-I lower limb gait robot. Both groups received 5 sessions a week for 4 weeks. Walking function parameters were assessed before and after the 4-week treatment. RESULTS: There was no significant difference in all parameters between the two groups in baseline (P > 0.05). After 4 weeks of treatment, all parameters including the effectiveness of functional ambulation category (FAC), time up and go test (TUGT) time, Wisconsin gait scale (WGS) score, walking spatiotemporal parameters were all significantly improved in both groups with a significant better effect in the intervention group (P < 0.05). CONCLUSION: Acupuncture combined with lower limb gait rehabilitation robot training has a positive effect on correction of abnormal gait and improvement of walking ability of hemiplegic patients after stroke.
Assessing the impact of the COVID-19 pandemic on latex glove usage and latex allergy complaints among nurses: A descriptive study
Authors: Koyuncu Aynur , Elagöz İslam , Yava Ayla
Published: January 2024

BACKGROUND: The coronavirus 2019 (COVID-19) pandemic has led to a significant increase in the use of latex gloves among nurses. However, concerns about the rise in latex allergies and related complaints due to this increase remain uncertain. OBJECTİVE: This study aims to assess the rates of latex glove usage and allergy-related complaints among nurses working in hospitals during the COVID-19 pandemic. METHODS: Between May 15 and June 15, 2021, ethical approvals were obtained for a cross-sectional study involving 448 volunteer nurses. Descriptive statistics were used to represent categorical values as counts (n) and percentages (%), while continuous values were represented as mean±standard deviation. The normal distribution of the data was assessed using the Kolmogorov-Smirnov and Shapiro-Wilk tests. Comparative analyses were conducted using paired sample t-test, Pearson’s chi-squared (x2) test, McNemar’s chi-squared (x2) test, and Spearman correlation analysis. RESULTS: Before the pandemic, the average number of invasive procedures was 45.13±26.48, whereas during the pandemic, this rate increased to 50.23±29.14. The average glove usage duration went from 7.69±3.13 hours to 14.73±3.68 hours during the pandemic. Among nurses, the rate of allergic symptoms, which was previously at 31.5%, rose to 33.3% during the pandemic. CONCLUSİON: This study revealed a significant increase in daily invasive procedures and the use of latex gloves among nurses during the pandemic period. Simultaneously, the frequency of allergic symptoms also rose. These findings underscore the importance of awareness and preventive measures, particularly regarding latex allergies, in the healthcare field.
Evaluation of driver drowsiness based on respiratory metrics
Authors: Khanehshenas Farin , Mazloumi Adel , Nahvi Ali , Nickabadi Ahmad , Aghamalizadeh Alireza , Keihani Ahmadreza
Published: January 2024

BACKGROUND: The transition from alertness to drowsiness can cause considerable changes in the respiratory system, providing an opportunity to detect driver drowsiness. OBJECTIVE: The aim of this study was to determine which respiratory features indicate driver drowsiness and then use these features to classify the level of drowsiness and alertness. METHODS: Twenty male students (mean age 25.6±2.41 years) participated in the study using a driving simulator, and eight features, including expiration duration (ED), inspiration duration (ID), peak-to-peak amplitude (PA), inspiration-to-expiration time ratio (I/E ratio), driving, timing, respiration rate (RR), and yawning, were extracted from the respiratory signal generated by abdominal motions using a belt equipped with a force sensor. RESULTS: All eight features were statistically significant at the significance level of 0.05. Drowsiness can be detected using respiratory features with 88% accuracy, 82% precision, 86% recall, and an 90% F1 score. CONCLUSION: The findings of this study may be useful in the development of driver drowsiness monitoring systems based on less intrusive respiratory signal analysis, particularly for specific process automation applications when vehicle control is not in the hands of the driver.
Severity-stratification of interstitial lung disease by deep learning enabled assessment and quantification of lesion indicators from HRCT images
Authors: Lai Yexin , Liu Xueyu , Hou Fan , Han Zhiyong , E Linning , Su Ningling , Du Dianrong , Wang Zhichong , Zheng Wen , Wu Yongfei
Published: January 2024

BACKGROUND:

Interstitial lung disease (ILD) represents a group of chronic heterogeneous diseases, and current clinical practice in assessment of ILD severity and progression mainly rely on the radiologist-based visual screening, which greatly restricts the accuracy of disease assessment due to the high inter- and intra-subjective observer variability.

OBJECTIVE:

To solve these problems, in this work, we propose a deep learning driven framework that can assess and quantify lesion indicators and outcome the prediction of severity of ILD.

METHODS:

In detail, we first present a convolutional neural network that can segment and quantify five types of lesions including HC, RO, GGO, CONS, and EMPH from HRCT of ILD patients, and then we conduct quantitative analysis to select the features related to ILD based on the segmented lesions and clinical data. Finally, a multivariate prediction model based on nomogram to predict the severity of ILD is established by combining multiple typical lesions.

RESULTS:

Experimental results showed that three lesions of HC, RO, and GGO could accurately predict ILD staging independently or combined with other HRCT features. Based on the HRCT, the used multivariate model can achieve the highest AUC value of 0.755 for HC, and the lowest AUC value of 0.701 for RO in stage I, and obtain the highest AUC value of 0.803 for HC, and the lowest AUC value of 0.733 for RO in stage II. Additionally, our ILD scoring model could achieve an average accuracy of 0.812 (0.736 - 0.888) in predicting the severity of ILD via cross-validation.

CONCLUSIONS:

In summary, our proposed method provides effective segmentation of ILD lesions by a comprehensive deep-learning approach and confirms its potential effectiveness in improving diagnostic accuracy for clinicians.
Noise Reduction of Aeromagnetic Data Using Artificial Neural Network
Authors: Elghrabawy Osama
Published: January 2024

The high-frequency content of high-resolution aeromagnetic data is of particular interest to geophysic ists to identify mineral deposits, shallow faults, and dikes. However, high-resolution aeromagnetic data is contaminated by cultural noise generated from aircraft and man-made features. The culture noise must be removed before starting the interpretation process. Manual techniques are more selective of the noise; however slower and more expensive because they require considerable hands-on interaction. The present study develops a novel method for detecting and removing the culture noise from aeromagnetic data based on an artificial neural network (ANN) in an automatic way and comparing the results with a conventional algorithm using the nonlinear filter. The proposed method is tested using a theoretical example that combine a magnetic anomaly due to a dyke with three sources of cultural noise, besides using a practical example to increase the number of training pattern. The network is trained based on the backpropagation training function, where the algorithm updates the weight and bias states as per the Levenberg–Marquardt optimization. The optimization is reached during the training and validation process after 3,000 iterations. The correlation coefficient ( R) is utilized along with the mean squared error (MSE) as performance indices of the ANN. The ANN demonstrates the capability to detect the spiky data based on the optimal weights, thus allowing for removing and replacing them with clean data using the piecewise cubic Hermite interpolating polynomial (PCHIP) function. The practical utility of the two-method is discussed using high-resolution aeromagnetic data from the Tushka area located in the southwestern desert of Egypt. Comparing the denoising results using the two methods shows that the current approach is more effective in processing and more closely recovering the original magnetic data.
The cosmological distances scale. Part 17: coincidence of coincidences
Authors: Levin S. F.
Published: January 2024

An alternative interpretation of the data is considered, on the basis of which in 1998–1999 a conclusion was made about the “acceleration of the expansion of the Universe”. The starting points of this interpretation were doubts about the legality of neglecting the effect of local emptiness, as well as a number of results obtained in solving measurement problems of cosmology. For this purpose, special programs “MMK-stat”, “MMK-stat M” and “MMI-verification” were used, designed to automate statistical data analysis in the tasks of verification and calibration of measuring instruments. The first two programs were used for the structural-parametric identification of the isotropic and anisotropic Friedman-Robertson-Walker models, respectively, in the form of a relationship between the photometric distance and the redshift of supernovae of type SN Ia in the class of power series. This dependence was analyzed as a mathematical model of the cosmological distance scale based on redshift. The gravitational dipole of inhomogeneity of the large-scale structure of the Universe is accepted as a physical mechanism for the mass accelerated motion of galaxy flows. A dipole of this kind consists of a pair of superclusters of galaxies and a giant void on opposite regions of the celestial sphere. The unbalance of the gravitational interaction in such a pair is perceived as an additional repulsive force of a comparable order with the influence of a supercluster. It is shown that there are at least five gravitational dipoles of this kind, which concentrate in the region of the galactic poles and form a giant Galactic polar gravitational dipole. It is shown that there are at least five gravitational dipoles of this kind, which concentrate in the region of the galactic poles and form a giant Galactic polar gravitational dipole, whose coincidence with the system of giant superclusters of galaxies in the Northern Galactic Hemisphere and the system of giant voids in the Southern galactic hemisphere is called “coincidence of coincidences”. This circumstance is considered as an alternative hypothesis to the hypothesis of “accelerating the expansion of the universe”. At the same time, it is not necessary to intro-duce exotic concepts of “dark matter” and “dark energy” to explain the observed facts.
Thermodynamic properties of refrigerant trans-1,3,3,3-tetrafluoropropene: method for constructing the fundamental equation of state and calculation of thermodynamic tables
Authors: Rykov S. V. , Popov P. V. , Kudryavtseva I. V. , Rykov V. A.
Published: January 2024

A new environmentally friendly fourth-generation refrigerant trans-1,3,3,3-tetrafluoropropene R1234ze(E) is considered as an alternative to R134a refrigerant in chillers and heat pumps, as well as R22 refrigerant in air conditioning systems. A technique has been developed for constructing a unified fundamental equation of state of liquid and gas, implemented for trans-1,3,3,3-tetrafluoropropene. The proposed fundamental equation in the vicinity of the critical point satisfies the requirements of the scale theory for asymmetric systems, and in the region of rarefied gas it is reduced to the virial equation of state. Based on this fundamental equation, tables of standard reference data on pressure, density, enthalpy, isobaric and isochoric heat capacities, entropy, heat of vaporization, and speed of sound, trans-1,3,3,3-tetrafluoropropene in the region of state parameters in the temperature ranges 169–420 K and pressure 0.1–100 MPa were calculated. A number of statistical characteristics have been calculated – absolute mean deviation, systematic deviation, standard deviation, root mean square deviation, which characterize the accuracy of the proposed fundamental equation in describing the experimental values of equilibrium properties obtained in generally recognized international thermophysical centers. It has been established that the values of these statistical characteristics are significantly less than the values of the corresponding characteristics of international fundamental equations given in the literature when describing thermal and caloric experimental data of trans-1,3,3,3-tetrafluoropropene. The estimated expanded uncertainties of the tabulated data obtained based on the proposed fundamental equation were 0.26 % for density, 0.57 % for pressure, 1.7 and 1.2 % for isochoric and isobaric heat capacities, 0.38 % for speed of sound. The results obtained allow us to conclude that the proposed unified fundamental equation of state adequately conveys the thermodynamic characteristics of trans-1,3,3,3-tetrafluoropropene in the specified range of temperatures and pressures.
The state primary standard of units of time, frequency and the national time scale GET 1-2022: contribution to the formation of Coordinated Universal Time
Authors: Noretz I. B. , Karaush A. A. , Kupalov D. S. , Smirnov Yu. F. , Donchenko S. I. , Denisenko O. V. , Slusarev S. N. , Fedotov V. N. , Khromov M. N.
Published: January 2024

Measurement of time and frequency is one of the most widespread types of measurements, information on the exact value of time, on the national time scale is extremely in demand by a wide variety of consumers, ranging from commercial electricity metering systems, where the required synchronization accuracy is a few seconds, to space navigation systems that impose requirements on synchronization at the level of units of nanoseconds. At the same time, consumer requirements for the accuracy of time and frequency measurements, as well as for the efficiency of obtaining time-frequency information, are steadily growing, which entails the need to modernize the means of reproducing, storing and transmitting units of time, frequency and time scale. To meet modern consumer requirements for the accuracy of time and frequency measurements, technical means of reproduction, storage and transmission of units have been introduced into the State primary standard of units of time, frequency and national time scale GET 1-2022, allowing to significantly increase the contribution of GET 1-2022 to the formation of the coordinated universal timescale UTC. A brief overview of the composition of GET 1-2022 is given, a comparative analysis of the contribution of time standards to the formation of the UTC timescale is carried out, as well as an analysis of the shifts of the time scales of the standards relative to UTC and the instability of the frequency standards. It is shown that from September 2022 to March 2023, the contribution of GET 1-2022 to the formation of the UTC increased significantly and exceeded that of the US Naval Observatory standard, and currently the contributions of these standards are comparable. In terms of frequency instability and average contribution to the formation of UTC, the atomic standards of GET 1-2022 are significantly superior to similar standard instruments from other countries. It has been established that the national coordinated time scale UTC(SU) is one of the best national implementations of UTC, and the national atomic time scale TA(SU) occupies a leading position among the time scales of leading foreign time laboratories in terms of instability.
Diffractive optical elements generation by layer-based methods for rapid and high-quality formation of 3D-objects
Authors: Zlokazov E. Yu. , Minaeva E. D. , Rodin V. G. , Starikov R. S. , Cheremkhin P. A. , Shifrina A. V.
Published: January 2024

The article is devoted to the generation of diffractive optical elements and computer holograms for forming three-dimensional images. Possibilities of increasing the speed of diffractive optical elements generation and the quality of reconstructed 3D-objects were investigated. Four methods of optical elements generation were analyzed. The methods use division the 3D-objects into fl at layers. The quality of 3D-object reconstruction and time generation by the methods were assessed. 3D-object reconstruction from generated optical elements was modeled. Optical formation of objects was performed by displaying optical elements onto liquid crystal spatial light modulator. It was found that the best quality of reconstruction was provided by iterative parallel ping-pong and non-convex optimization methods. The optimal ratio of reconstruction quality to generation speed ratio was obtained for the parallel ping-pong method. The possibility of fast formation high-quality three-dimensional scenes consisting of dozens of layers has been demonstrated.
Analysis of operation models of complex technical systems
Authors: Ershov D. S. , Malakhov A. V. , Talala A. V. , Khairullin R. Z.
Published: January 2024

A retrospective analysis of existing models of operation of complex technical systems with metrological support has been carried out. The models of failures and degradation of complex technical systems based on diffusion monotone and diffusion non-monotone distributions, the model of failures and degradation of complex technical systems based on three-parameter diffusion distribution are described. Failure and degradation models are used together with the classical model of E. I. Sychev and more complex models developed on its basis. For complex technical systems that allow full resource recovery during repair, a model of operation of complex technical systems has been developed, taking into account 4 degrees (groups) of degradation of complex technical systems. The model is described by a system of linear algebraic equations of the 21st order. The functional dependence of the stationary readiness coeffi cient on the calibration intervals of measuring instruments included in complex technical systems of various degradation groups is constructed. For complex technical systems that do not allow full restoration of the resource during repair, a model of operation of complex technical systems has been developed, taking into account 3 groups of degradation of complex technical systems. The model is described by a system of linear algebraic equations of the 24th order. The model allows you to simulate the main stages of the life cycle of a fl eet of complex technical systems, including, among other things, the processes of updating a fl eet of complex technical systems through the purchase of new samples and upgrades, existing samples of complex technical systems. The models presented in the article allow calculating optimal values of intervals between verifi cations and optimal values of tolerances for controlled parameters for different groups of degradation of complex technical systems with metrological support, ensuring the maximum level of stationary availability coeffi cient. The developed set of models can be used to classify complex technical systems in order to set requirements for their metrological support. The models can also be used to calculate the technical and economic indicators of the development of a fl eet of complex technical systems.
State primary volt standard of the fourth generation
Authors: Katkov A. S. , Shevtsov V. I. , Gromova J. A.
Published: January 2024

The results of scientifi c research aimed at improving the State primary standard of electrical voltage unit GET 13-01, built on the basis of the Josephson quantum effect, are presented. In the process of improving GET 13-01, the following tasks were solved: the range of reproduction of constant voltage was expanded as a result of the transition from two reference points with nominal voltage values of 1 and 10 V to the range of 1·10–3–10 V; increased noise immunity of the reproducible voltage due to the introduction of a voltage measure with a hysteresis-free Josephson array; the stability of the reproduced voltage is ensured; the process of transferring a unit of voltage to both voltage measures and voltage meters is automated; the process of setting the specifi ed voltage in the time domain is provided. The improved GET 13-01 was approved with a new composition as the State Primary Standard of the unit of electrical voltage GET 13-2023. GET 13-2023 uses quantum voltage measures based on various types of Josephson arrays. The metrological characteristics of GET 13-2023 are studied in the process of comparisons of quantum measures included in its composition (with hysteresis and hysteresis-free Josephson arrays). GET 13-2023 provides reproduction of the unit of electrical voltage with a standard deviation of the measurement result of not more than 1·10–9 V, a non-excluded systematic error of not more than 1·10–9 V in the voltage range of 1·10–3–1 V and provides reproduction of a unit of electrical voltage with a standard deviation of the measurement result in the voltage range of 1–10 V not more than 10–9 multiplied by the value of the reproduced voltage, a nonexcluded systematic error of not more than 10–9 multiplied by the value of the reproduced voltage. The obtained results are relevant for ensuring the uniformity of measurements in the fi eld of constant voltage and for conducting international key comparisons.
The results of navigation spacecrafts observations with asymmetry of the onboard antenna amplitude radiation pattern
Authors: Zavgorodnii A. S. , Voronov V. L. , Ryabov I. V. , Chigvincev A. A.
Published: January 2024

The received in the Earth surface layer satellite radio signal power depends on the space navigation vehicle onboard antenna parameters, primarily it depends on the amplitude radiation pattern shape. The spacecraft onboard antenna radiation pattern has a complex shape in order to compensate for radio navigation signal power changes as a result of the removal (or approach) of the navigation satellite from the signal consumer. For this reason, the shape of the radiation pattern must have axial symmetry, i.e. it has to be close to the rotation fi gure. As a result of the global navigation satellite system GLONASS radio navigation signals energy characteristics monitoring, VNIIFTRI evaluated amplitude radiation patterns of the onboard antenna-feeder devices of satellites from the orbital constellation, the amplitude radiation patterns asymmetry of some of them was discovered. The asymmetry of the radiation pattern leads to the radio navigation signal (received by the consumer) power dependence on the device angle of the, i.e. on the position of the onboard radiating antenna system of the relative to the signals consumer. The probable reason for the asymmetry is the gradual aging of the active devices in the antenna system. The article purpose is to pay attention of competent specialists to the existing problem.
Determination of ef ective thickness of cemented steel layer
Authors: Sandomirski S. G. , Val'ko A. L. , Rudenko S. P.
Published: January 2024

The problems of increasing the strength of high-loaded steel parts of transmissions of energy-saturated machines are considered. It is noted that, along with hardness, an important parameter of the hardened cemented steel layer is its effective thickness the distance from the surface of the sample (part) to the zone with hardness 50 HRC (529 HV0.5). It is shown that great infl uence on accuracy of its defi nition have unavoidable banding of metal in the area of hardness measurement and an instrumental error of hardness measurement. A method of increasing the accuracy of determining the effective thickness of the cemented layer, based on interpolation by polynomial of the second degree of distribution of experimentally measured hardness values HV0.5 in an extended range of changing distances from the surface of the article to the hardness measurement HV0.5 is offered. Error of defi nition of an effective thickness of the cemented layer is reduced at the expense of expansion of area of change of hardness HV0.5 in an analyzed zone with approximation of its monotonous change in this area and the subsequent solution of the received square equation. Approximating polynomial statistically correctly refl ects the character of hardness change HV0.5 of cemented steel in the analyzed area depending on the distance from the workpiece surface to the hardness measurement place. The effectiveness of the method was confi rmed when determining the effective thickness of the grouted layer of a sample of 18CrNiGt steel after carburizing and hardening. The obtained results will be useful in the development of optimal regimes of carburizing of high-loaded gearwheels of automobile and tractor transmissions.
State primary standard of unit of the mass concentration of oxygen, hydrogen and carbon dioxide in liquid media GET 212-2023
Authors: Stakheev A. A. , Dobrovolskiy V I. , Stolboushkina T. P.
Published: January 2024

The accuracy of measurements of the mass concentration of dissolved carbon dioxide and the requirements for the accuracy of such measurements, namely, the relative error of measurements of the mass concentration of carbon dioxide (about 10 %) at the enterprises of the Russian industry are investigated. The issues of ensuring the uniformity of measurements and achieving metrological traceability of the measurement results of the mass concentration of carbon dioxide in liquid media to the state primary standard are considered. The State primary standard of units of mass concentration of oxygen, hydrogen and carbon dioxide in liquid media GET 212-2023 is described. The GET 212-2023 includes new technical means: systems of gas supply and gas mixing of carbon dioxide, measurement system of dissolved carbon dioxide. Gas supply and gas mixing systems implement the reproduction method. A software-controlled measuring system is used to measure the mass concentration of dissolved carbon dioxide. A method of reproducing the unit of mass concentration of dissolved carbon dioxide based on the Henry-Dalton law is described. The results of studies of metrological characteristics of GET 212-2023 are presented. For the fi rst time, the fundamental possibility of reproducing the unit of mass concentration of dissolved carbon dioxide in the range from 0 to 15 g/dm3 with a relative non-excluded systematic error not exceeding 2.5% has been achieved in the Russian Federation. GET 212-2023 will ensure current requirements in various industries, such as food, pharmaceutical and chemical, as well as in the fi eld of environmental protection, electronics and semiconductor technologies.
Areas of improvement of measuring systems and their metrological support
Authors: Danilov A. A.
Published: January 2024

The actual task of analyzing the features of measuring systems and their metrological support is formulated. Promising directions for the development of measuring systems, including virtual ones, were considered. An analysis of such areas of development of measuring systems as remote and synchronized vector measurements, cloud technologies, the Internet of Things, big data and artifi cial intelligence was carried out. An analysis of some innovative solutions was carried out, based both on the use of biological sensors and on the use of hybrid metrology - on the introduction of structural redundancy in the composition of measuring systems, as well as temporary and algorithmic redundancy in the software of measuring systems. As a result of the review, it is concluded that the integration of component functions is an objective diffi culty in highlighting measuring systems as part of complex technical systems, but gives more and more new capabilities to technical systems with measuring functions. An analysis of such areas of improvement of metrological support of measuring systems as self-diagnostics and self-monitoring, remote and automated calibration and verifi cation, the use of digital twins, big data and artifi cial intelligence, as well as the establishment of adaptive intervals between calibrations and checks was carried out. The conclusion concludes on the need to minimize bureaucratic procedures, automate metrological procedures, and the expediency of switching from periodic to adaptive procedures, mainly without human participation.
A fast algorithm for decoding an object image in structured light for measuring a three-dimensional profi le in a non-linear optical path
Authors: Dvoynishnikov S. V. , Bakakin G. V. , Pavlov V. A. , Meledin V. G.
Published: January 2024

The work is devoted to the development of image processing algorithms for measuring a three-dimensional surface profi le using phase triangulation methods. An algorithm for decoding images of an object in structured light is proposed, based on an iterative search for the minimum deviation of the model function from the measurement results and compensating for the nonlinearity of the receiving-transmitting path of the measuring complex. A distinctive feature of the proposed method is that the search for the model function is sought in the form of a polynomial of the second degree, which ensures the stability of the method against nonlinear distortions caused by power-law transformations of the receiving-transmitting path. The use of the interval search method as part of the proposed algorithm provides a qualitative reduction in its algorithmic complexity. It is shown that the proposed algorithm provides a stable search for the value of the initial phase shift in object images, is resistant to noise and non-linear distortions. The algorithm proposed in the paper can be used to process images received in three-dimensional scanning systems based on triangulation methods using structured illumination and phase triangulation. The proposed algorithm will be especially useful for data processing during the operation of measuring systems in the conditions of a nonlinear source-receiver path of optical radiation and measurement time limitations.
The history of the development of the capillary method of measuring kinematic viscosity: from the Lomonosov viscometer to the information measuring system
Authors: Mirgorodskaya A. V.
Published: January 2024

The history of the development of the capillary method of viscosity measurements is described and the tasks of automation and improvement of this method are considered. A comparative analysis of the currently relevant vibrational, rotational, capillary methods of measuring the viscosity of a liquid and the measuring instruments implementing them is given. The State verifi cation scheme for viscosity measuring instruments to represent the role of the capillary method in general and glass capillary viscometers in particular in this structure is briefl y described. The reasons why the capillary method is used in many countries as the main high-precision method for measuring the viscosity of liquids are considered. A detailed derivation of the formula for calculating the kinematic viscosity of the liquid under study is given. As one of the possible ways to further develop the capillary method of measuring kinematic viscosity, it is proposed to create an information-measuring system for measuring the kinematic viscosity of the liquid under study. The principle of operation of this system is described and plans for its implementation are formulated. It is shown that it is possible to increase the accuracy of measurements of the viscosity of liquid media by the capillary method by automating measurements and installing detectors of a certain type. The results of the performed analysis are relevant to ensure the uniformity of viscosity measurements in the Russian Federation.
Vacuum large-aperture blackbody model in the temperature range 223.15–423.15 K for radiometric calibration of optoelectronic equipment for Earth observation
Authors: Dovgilov N. L. , Morozova S. P. , Alekseev S. V. , Dunaev A. Yu. , Gavrilov V. R. , Dmitriev I. Yu. , Linskyi P. M. , Vasiliev V. N.
Published: January 2024

The structure of the systems for the radiometric calibration of the remote sensing optoelectronic equipment in the infrared spectral range is presented. The analysis of existing facilities for the radiometric calibration of the remote sensing optoelectronic equipment in conditions of vacuum and low-background radiation was carried out. These facilities are based on using of the blackbody models as radiation sources, including reference sources based on the phase transition of pure metals, for example gallium or indium. The wide-aperture blackbody model LABB-380 with an aperture diameter of 380 mm in the temperature range from 223.15 K up to 423.15 K has been developed for a high-vacuum low-background stand, which is currently being developed at the Sciences Research Institute of Optoelectronic Instrumentation for the radiometric calibration of the remote sensing optoelectronic equipment. The results of calculating the normal effective emissivity of the surface of the LABB-380 in the temperature range from 223.15 K to 423.15 K in the spectral range from 3 to 20 μm are presented. The metrological characteristics of LABB-380 obtained during the transmission of a temperature unit from the zero discharge State Standard using a comparator based on the precision pyrometer HETRONIXS are investigated and presented. The instability of the LABB-380 radiation was 0.005 K according to the calibration results in the temperature range from 300.15 K to 390.15 K, and the extended temperature uncertainty was 0.66 K at the temperature of 300.15 K and 0.88 K at a temperature of 390.15 K.
Device for measuring the Seebeck coeffi cient of thermoelectric materials in the temperature range 300–800 K
Authors: Karpov A. V. , Sytschev A. E. , Sivakova A. O.
Published: January 2024

The problem of identifying patterns that are associated with the features of the structure and phase composition of new thermoelectric materials obtained by self-propagating high-temperature synthesis is considered. A measuring device has been developed to determine the Seebeck coefficient (thermoelectric motive force) of thermoelectric materials in the temperature range of 300–800 K in argon, air or vacuum. The design of the measuring device is described in detail, the capabilities of the device and the measurement error (less than 5 %) are discussed. The thermoelectromotive force of reference nickel samples in the temperature range of 300–800 K in an argon medium was measured by a differential method. Negative values of the Seebeck coefficient of the nickel sample were obtained throughout the studied temperature range, which indicates the predominance of electrons as the main charge carriers in the sample material. At room temperature, the measured value of the Seebeck coefficient is –19.05 mkV/K and decreases to a value of –25.71 mkV/K with an increase in temperature to 515 K. With a further increase in temperature to 640 K, the Seebeck coefficient monotonically increases to a value of –19.60 mkV/K. At temperatures above 640 K, the Seebeck coefficient continuously decreases and at 824 K reaches a value of –24.12 mkV/K. The Curie point is 644 K. The obtained values of the Seebeck coefficient for nickel in the temperature range 300–800 K are comparable with the data given in the literature. When calculating the Seebeck coefficient of the material, equations are used using the Seebeck coefficient values for the positive and negative thermocouple paths, which eliminates the need for additional measuring probes and contacts to measure the thermoelectric voltage on the sample. The set-up can also be used to make electrical resistance measurements using the standard 4-point method.
Metrological support of digital electronic voltage transformers and low-power voltage transformers
Authors: Grishin M. V. , Leonov A. V. , Kucobin A. A.
Published: January 2024

Metrological support of digital electronic voltage transformers and low-power voltage transformers (sensors) is represented. The methods and reference measuring instruments of the State primary special standard of units of the ratio error and the phase displacement of AC electric voltage of power frequency in the range from to and units of electric capacitance and tangent of loss dissipation factor at AC voltage of power frequency in the range from 1 to 500 kV – GET 175-2023, used for metrological support of the measuring instruments mentioned above. The results of research of GET 175-2023 are presented. The expanded uncertainties of GET 175-2023 when reproducing the units of the ratio error and the phase displacement of AC electric voltage of power frequency for metrological support of analog low-power voltage transformers (sensors) include the budget of the uncertainties of the current comparator, low-voltage (reference) and high-voltage measuring measures, the high-voltage MVE-01 bridge (SA7400MA1 amplifi er) and are respectively 9.62·10–5 and The expanded uncertainties of GET 175-2023 when reproducing the units of the ratio error and the phase displacement of AC electric voltage of power frequency for metrological support of electronic digital voltage transformers and digital low-power voltage transformers (sensors) include the budget of uncertainties of the converter «high voltage – current», converter «current – low voltage», converter «low voltage – a digital copy of voltage», a digital comparison device and constitutes 10.8·10–5 and respectively. GET 175-2023 allows solving the problems of metrological support of electronic digital voltage transformers and digital low-power voltage transformers (sensors).
Determination of components of losses in the steel of the magnetic circuit of electric machines
Authors: Plotnikov S. M. , Iksil N.
Published: January 2024

The division of total losses in electrical steel of the magnetic circuit of electric machines into three components is considered: hysteresis, classical eddy current and anomalous eddy current. The solution to this technical problem will make it possible to effectively design and construct electrical machines with magnetic cores having low magnetic losses. At present, such a separation of losses is associated with time-consuming measurements on special equipment and is performed with large errors. Each of these components depends differently on the magnetization frequency and temperature, and these dependences are known. Based on this, the paper proposes two methods for determining losses in steel – the method of three frequencies and the method of three temperatures. In order to fi nd three unknown quantities, three no-load experiments are proposed, carried out at three frequencies or at three temperatures of electric machine cores. Using the results of measurements of active powers spent on core heating, expressions of hysteresis, eddy-current classic and eddy-current anomalous losses are obtained. The results of the experiments carried out by the method of three frequencies and the method of three temperatures agree well with each other, which confi rms the adequacy of the methods and the possibility of their application in practice. The article analyzes the advantages and diffi culties of implementing each method. The methods can be applied to effectively minimize losses in the steel of electrical machines.
The effect of the nanosilica/oligochitosan hybrid material on the growth of lettuce (Lactuca sativa L. var. longifolia)
Authors:   Department of Polymer and Composite Materials, Faculty of Materials Science and Technology, University of Science, Hoang Dongquy ,   Vietnam National University Ho Chi Minh, Vietnam., Nguyen My Xuyen ,   Department of Polymer and Composite Materials, Faculty of Materials Science and Technology, University of Science; Vietnam National University Ho Chi Minh, Vietnam., Ngan Nguyen Nguyen ,   Department of Polymer and Composite Materials, Faculty of Materials Science and Technology, University of Science; Vietnam National University Ho Chi Minh, Vietnam., Ngoc Nguyen Thuy ,   Department of Polymer and Composite Materials, Faculty of Materials Science and Technology, University of Science; Vietnam National University Ho Chi Minh, Vietnam.
Published: January 2024

A nanostructured hybrid material prepared from eco-friendly natural materials such as nanosilica (nSiO2) extracted from rice husk and oligochitosan (OS) isolated from shrimp shells is material of high promise with special properties to be applied in various fields, especially in agriculture. In this study, hybrid nanosilica material based on oligochitosan (SOS) with a concentration of 50 mg/L as nutrient source was supplied to the lettuce (Lactuca sativa) at different stages of growth. The two-week-old lettuce (H2W2) supplied with the hybrid material had an increase in leaf length by 17.24% and root length by 5.26% in comparison with those of the control lettuce. Additionally, the fresh weight and leaf number of the hybrid-supplied plant were 20.39% heavier and 9.09% higher than those of the control samples, respectively. Moreover, the chlorophyll measurement indicated that the total chlorophyll content of H2W2 was 7.61% higher than that of the control, and the plant growth characteristics also increased by 20.39% compared with the control plant. The SOS hybrid material could be seen as a green agrochemical with a great promise of being applied in the modern agriculture. This kind of renewable material also contributes to replacing and declining the numbers of the type of toxic chemical fertilizers and plant protection products used on the market today.