Informatyka, Automatyka, Pomiary w Gospodarce i Ochronie Środowiska

4-9

Authors: Serhii Moroz, Anatolii Tkachuk, Mykola Khvyshchun, Stanislav Prystupa, Mykola Yevsiuk

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) is presented. The main algorithms for ensuring the confidentiality and security of mobile subscribers' data, in different types of standards, as well as the vulnerabilities of information flows are considered. In particular, the following dangerous types of attacks have been identified, to which mobile network subscribers are sensitive: sniffing; leakage of personal data; leakage of geolocation data; spoofing; remote capture of SIM-card, execution of arbitrary code (RCE); denial of service (DoS). It is established that the necessary function of the mobile network is the identification of subscribers, which is performed by IMSI, which is recorded in the SIM card of the subscriber and the HLR of the operator. To protect against spoofing, the network authenticates the subscriber before starting its service. In the case of subscriber identification, the subscriber and the network operator are protected from the effects of fraudulent access. In addition, the user must be protected from eavesdropping. This is achieved by encrypting the data transmitted over the radio interface. Thus, user authentication in UMTS, as well as in the GSM network, is carried out using encryption with a common key using the "hack-response" protocol (the authenticating party sends a random number to the authenticated party, which encrypts it according to a certain algorithm using a common key and returns the result back).

15-19

Authors: Dominik Gnaś, Przemysław Adamkiewicz

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 technology is explained. Bluetooth technology is discussed, which is used to connect the location system with the environmental monitoring system.

24-27

Authors: Damian Harasim

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 indices of the surrounding medium and the fiber cladding. With the introduction of a small inclination angle of the diffraction fringes forming the Bragg grating, the cladding modes show sensitivity to changes in the refractive index of the environment of aqueous solutions, which makes the spectrum of their applications broad. This publication presents changes in the spectra of selected modes measured for solutions with a specific refractive index, shift sensitivity, and changes in the mode transmission coefficient and processing characteristics at a selected concentration range of solutions. Experimental results show that high order cladding modes respond both by shifting the central wavelength as well as by changing the transmission minimum. In selected ranges, these parameters show a linear characteristic as a function of changes in the concentration of the cane sugar aqueous solution. In the case of TFBG with a tilt angle of 8 °, the sensitivity of wavelength changes is 0.012nm / RIU for solutions with concentrations ranging from 0% to 10% by weight.

36-39

Authors: Aleksandra Wilczyńska, Karolina Czarnacka, Andrzej Kociubiński, Tomasz Kołtunowicz

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 of the obtained structures in the range from 4 Hz to 8 MHz was studied. Additionally, in order to compare the non-oxidized and oxidized layers, some of them were heated at 500 °C. Based on the results obtained, the mechanism of electric charge transfer was determined, the knowledge of which is essential for planning further experiments based on this sputtering method and potential selection of future application of the structures. Statistical measurements at room temperature will serve as a reference for the conductivity and resistivity values obtained by mathematical calculations from measurements of resistance, capacitance, phase shift angle, and dielectric loss tangent as a function of temperature from 20 K to 375 K, which are expected in further studies on the obtained structures. The work is an introduction to the technology of obtaining multi-layer metal-dielectric structures.

44-46

Authors: Oleksii Perepelytsia, Tetyana Nosova

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 algorithms, you can segment tooth root structures with high precision. Therefore, the combination of electronic determination of the root canal length (using apexlocator) with X-ray segmentation is relevant.