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In this paper, the transport properties of discontinuous 4 nm copper layers obtained by dual-source non-reactive magnetron sputtering in the presence of argon are presented. The value of resistance and capacitance of the current parallel to the plane of these layers can be adjusted independently by changing the nominal thickness of the metallization. The influence of frequency on the conductivity...
The article presents the results of research in the area of using deep neural networks to identify moisture inside the walls of buildings using electrical impedance tomography. Two deep neural networks were used to transform the input measurements into images of damp places - convolutional neural networks (CNN) and recurrent long short-term memory networks LSTM. After training both models, a comparative...
Apexlocators are devices that determine the working length of the root canal. Measurement with the help of alternating currents of different frequencies in combination with the method of the ratio allows to achieve high accuracy in determining the location of the physiological tip of the root (over 80%). However, such devices cannot accurately visualize where a doctor's tool is. Using image processing...
This paper discusses two ways of measuring the distance between the transmitter and the receiver using UWB technology, then identifies their advantages and disadvantages. The method of calculating the position is presented together with the method of predicting errors based on room geometry. The hardware configuration of the transmitter and receiver systems included in a location system based on UWB...
The analysis of mobile communication standards is carried out, the functional structure and interfaces of interaction between the structural elements of the cellular network are considered. To understand the principle of communication according to the GSM standard, a block diagram of a mobile switching center (MSC), base station equipment (BSS), control and service center (MCC), mobile stations (MS)...
This article describes the design and implementation of a hybrid in-building navigation system. The word hybrid has a twofold meaning in this case. On the one hand, it refers to the use of two tracking methods: demanding (beacons) and not requiring an electronic device (radio tomography imaging). On the other hand, it specifies several commercial wireless communication protocols that make up the presented...
This publication presents the basic assumptions about the light guiding mechanisms in tilted fiber Bragg gratings, transmission spectra of the fiber with such structures and their sensor properties related to the occurrence of the so-called cladding modes. The light in the form of modes coupled to the optical fiber cladding causes their spectral properties to depend on the difference in the refractive...
Melanoma is currently one of the most dangerous skin diseases, in addition many others appear in the population. Scientists are developing techniques for early non-invasive skin lesions diagnosis from dermatoscopic images, for this purpose neural networks are increasingly used. Many tools are being developed to allow for faster implementation of the network, including the Keras package. The article...
The aim of the presented project was to create a comprehensive building management system equipped with a network of wireless and energy-efficient sensors that collect data about users and on their basis control final devices such as lighting, ventilation, air conditioning and heating. In the presented system, end devices can be both products offered by the market (commercial) and proprietary solutions...
The dynamic processes of the system of stabilization of the speed of the conveyor belt with a built-in hydraulic drive on the basis of an improved mathematical model, which takes into account the physical phenomena occurring in the hydraulic system during the action of alternating load. The influence of the main parameters of the hydraulic system and the magnitude of the load on the course of dynamic...
The analysis of factors and approaches to the conditioning of the electromagnetic impact of 330 kV overhead transmission lines on ecological systems has been carried out. The analysis performed enabled to reveal that the world experience, recording the introduction of the transmission lines of the carrying capacity and reduced environmental impact, including the compact and controlled self-compensating...
The paper regards the urgency of creating small - sized systems for automated local sorting of household waste for modern residential complexes based on visual spectrometry. For this purpose, algorithms for system operation were developed and the procedure for designing a functional control scheme for the sorting process with the construction of the necessary contours of automated control was presented.
The problem of creating mathematical models of nonlinear dynamical systems does not have an unambiguous solution and requires the creation of a separate synthesis method for each such object. To develop a method for synthesizing mathematical models of an extensive class of nonlinear dynamical systems with polynomial nonlinearities. The work uses a method based on the solution of the Volterra integral...
Skin diseases diagnosed with dermatoscopy are becoming more and more common. The use of computerized diagnostic systems becomes extremely effective. Non-invasive methods of diagnostics, such as deep neural networks, are an increasingly common tool studied by scientists. The article presents an overview of selected main issues related to the multi-class classification process: the stage of database...
The paper presents a numerical electromagnetic simulations of SAR limited to human tissues based on FDTD algorithm using Sim4Life platform. Flat-bottomed dielectric vessel (flat phantom) and half-wave symmetric dipole antenna were modeled. Simulations were done for the frequencies 0.9 GHz and 0.6 GHz. The analysis were performed according to the IEEE/IEC62704-1 standard and include distributions of...
The article provides an analysis of the physical processes underlying the operation of the measuring transducer, with a time based information presentation. A mathematical model is developed that describes the process of free oscillation attenuation excited in the LC-contour of primary measuring transducer, and analyzes and evaluates the influence of external factors that influence the measurement...
Different algorithms are used for the quantitative interpretation of optical spectra. Regression methods e.g CLS (Classical Least Squares) or PLS (Partial Least Squares) are often used in typical problems of laboratory spectroscopy. The spectra analysis is generally a multi-step process, in which, depending on the spectra type, modification of individual regression methods or special dedicated methods...
The article describes the progress of construction and research works on ultrasound tomography. The devices allow for non-invasive measurements of various objects using ultrasonic low and high-frequency transducers. The first constructions were made in a dispersed system with active measurement probes using 40 kHz converters. The next constructions were centralized into one measurement system where...
The accuracy of the calculation of acoustic problems formulated in the frequency domain is presented in this work. The issues of the acoustic point sources modelling were discussed and the influence of frequency as well as the impact of the geometry of the analysed area on the accuracy of calculations were indicated. Speaking about the influence of geometry, we mean not only discretization but also...
A new magnetically sensitive element based on the synthesized semiconductor material has been developed. A method for the synthesis of a complex compound has been developed tetrakis-μ3-(methoxo) (methanol)-pentakis (acetylacetonate) (tricuprum (II), neodymium (III)) methanol (I). Conducted properties have been studied complex compound in compressed form in the temperature range 273 - 493 K. In the...
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