Journal of Communications Technology and Electronics最新文献

Abstract

Methods for constructing distributed automation systems for circuit design to calculate the instability of the coordinates of the operating points of the static mode of nonlinear electronic circuits were considered. Two-terminal networks of type R and transmission parameters of dependent sources, as well as characteristics of external influences (temperature, radiation, etc.) are taken as components that change under the influence of external factors. To solve the problem of calculating the instability of the coordinates of the operating points of the static mode of nonlinear electronic circuits, a technique is proposed based on the use of an auxiliary circuit, which is constructed by transposing the description of the original circuit. The features of the organization of serverless and microservice architecture for building circuit design automation systems are analyzed. The multitenant design of a microservice information system environment is described. The mechanism of operation of the service as a service is presented to ensure the operation of the business logic of the server component.

Abstract

A method of empirical evaluation of the transient response of an aperture-type antenna when it is excited by a video pulse has been proposed. The evaluation was carried out on the basis of comparing the excitation voltage of the antenna and the excitation voltage of the radiating aperture, which is calculated using the parameters of the emitted pulse. An evaluation of the energy efficiency of a given antenna as a converter of electrical energy into radiation energy has been given through variations in the antenna length and duration and shape of its excitation pulse.

Abstract—

The features of calculating the matrices of per-unit-length parameters and characteristics of multiconductor transmission lines have been considered. The method of calculation of the matrices of primary per-unit-length parameters of multiconductor transmission lines has been presented. The criteria for the accuracy of the calculation of the capacitance matrix have been formulated. It has been noted that it is necessary to accurately account for the mutual influence between the transmission line conductors for a correct estimation of the distortions of the signals propagated in it. The influence of the per-unit-length parameters of multiconductor transmission lines on responses and eye diagrams at the end of their active conductors has been demonstrated. The influence of the distances from the extreme conductors to the boundaries of the cross-sections of transmission lines on the accuracy of calculating their capacitance matrices has been studied. Using the method of moments, it has been shown that known approaches to determining these distances do not always give accurate or efficient results. On the example of several transmission lines with different numbers of dielectric layers and conductors, as well as with the shield and without it, the minimum values of this distance at which it is possible to achieve an accurate and efficient calculation of their capacitance matrices have been determined.

Abstract

A 2.5D hybrid model is used to numerically study the interaction of a beam with a current of 2.5–7.5 kA and an electron energy of 345–510 keV and terahertz (364–368 GHz) electromagnetic field. It is shown that Bragg reflectors in an electrodynamic system with an overmode ratio of 49 make it possible to significantly suppress backward radiation and multiply increase the radiation power in the direction of the electron beam. Radiation pulses with a power of up to 330 MW are obtained in calculations with disregard of heat loss in the presence of a guiding magnetic field of 6 T.

Abstract

In promising data transmission systems, new management solutions can be used, for example, we can divide network elements into network layers or implement network elements in the form of virtual network functions. In promising networks, regional centers are software controllers that control local sensors. All control centers are interconnected through a transport subsystem and are included in one network. Sensors provide monitoring of the ability of various types of traffic. One of the most important tasks of traffic management is its filtering. In promising systems, this problem is solved on network sensors by implementing algorithms for matching traffic information and filtering rules. The article proposes an approach to using the concept of software-configurable networks and virtualization of network functions to implement a traffic management system in promising mobile networks. It is proposed to use switches based on the OpenFlow protocol as network sensors. The article also proposes a method for processing and filtering traffic in transport networks, which is implemented in the form of a set of libraries and drivers for interacting network elements directly with applications, which reduces the search time for the necessary rules on telecommunications equipment.

Abstract—A platform for monitoring and analysis of the seismogenic processes is described. The platform consists of two separate GISs. The first system, Web GIS Prognosis, downloads and processes data from remote servers and is used in the systematic Web earthquake prediction and preparation of a project for further analysis. The second system, spatiotemporal GIS GeoTime 3, provides opportunities for detailed study of the data prepared in the GIS Prognosis. Examples of the data analysis results on this platform are presented. The potential of systematic observation of the seismological situation in the GIS Prognosis is demonstrated by the example of California. Using the GIS GeoTime, the efficiencies of the methods for estimating the earthquake epicenter density fields when predicting earthquakes in Kamchatka are compared and it is shown that adaptive weight smoothing yields the best result.

Abstract—Computer-aided detection (CAD) systems are used by radiologists as a second interpreter for breast cancer detection in digital mammography. However, for every true-positive cancer detected by the CAD system, a large number of false predictions must be reviewed by an expert to avoid an unnecessary biopsy. The traditional approach to creating such systems is to select and compute the features of objects of interest from the source data, followed by the selection of a model for their classification using machine learning. Machine learning and, especially, deep learning are being used to analyze mammograms. Most of the models proposed so far are trained on a small amount of data and do not have high reliability. This paper compares several deep learning models for benign–malign mammography classification on digital mammograms. The preprocessing step is designed to remove noise and extract features using local phase information of the image. Deep learning is then used to classify the digital mammography. The experimental results are presented using several databases and estimated using several quality criteria.

Abstract

It was shown for the first time that when nickel is deposited onto a heated gallium antimonide substrate, diffusion of antimony atoms from the substrate into the growing film occurs and a nickel antimonide film is formed, which has an axial texture with an axis perpendicular to the film plane along the (101) direction.

Abstract—A solution to the problem of compiling decision rules for determining possible oil and gas fields in the territory of Western Siberia by the method of monotonic functions is proposed. The method is based on a model in which the decision rule is sought in the class of monotonic functions on the feature space. This method was applied first to solving the binary classification problem when choosing the type of operation for patients with prostate cancer. In this paper, an example of applying the method to the classification problem in geosciences is considered. The results of the method showed quite high estimates of the probability of identifying possible deposits, with fairly low error probabilities.

Abstract

The possibility of coherent summation of chaotic radio pulses in a wireless channel has been demonstrated experimentally. A method for obtaining chaotic radio pulses having an initial section with oscillations similar in shape is described. Chaotic radio pulses are generated and emitted by independent, structurally identical generators of chaotic oscillations, each of which is modulated by a sequence of video pulses of power supply. It is shown that at the output of an antenna receiving signals from two emitters, coherent summation of chaotic radio pulses is observed.