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Search results for: AD HOC NETWORK
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Simulation model for evaluation of QOS dynamic routing
PublicationCurrent informational networks use a large variety of technologies to support data exchange. Most of them are focused on IP protocol and include mechanisms which by definition should supply demanded QoS. One of those mechanisms is efficient path calculation - routing. Traffic offered to the network can change very rapidly in short term. Routing should support such traffic changes and all the time calculate valid paths in terms...
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Distributed protection against non-cooperative node behavior in multi-hop wireless networks
PublicationAn important security problem in today's distributed data networks is the prevention of non-cooperative behavior i.e., attacks consisting in the modification of standard node operation to gain unfair advantage over other system nodes. Such a behavior is currently feasible in many types of computer networks whose communication protocols are designed to maximize the network performance assuming full node cooperation. Moreover, it...
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Dynamic unattended measurement based routing algorithm for diffServ architecture
PublicationDynamic routing is very important in terms of assuring QoS in today's packet networks especially for streaming and elastic services. Existing solutions dedicated to dynamic routing are often too complicated and seem to be not usable in real time traffic scenarios where transferred traffic may vary significantly. This was the main reason for research and new routing mechanism proposal which should apply to today's packet networks....
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Message Inter-Arrival and Inter-Departure Time Distributions in IMS/NGN Architecture
PublicationCurrently is it assumed that requirements of the information society for delivering multimedia services will be satisfied by the Next Generation Network (NGN) architecture, which includes elements of the IP Multimedia Subsystem (IMS) solution. In order to guarantee Quality of Service (QoS), NGN has to be appropriately designed and dimensioned. Therefore, proper traffic models should be proposed and applied. This requires determination...
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RECODIS: Resilient Communication Services Protecting End-user Applications from Disaster-based Failures
PublicationDisaster-based failures can seriously disrupt any communication network, making its services unavailable. Such disruptions may be caused by natural disasters, technology-related failures, or malicious attacks, and they are observably increasing in number, intensity and scale. When network services that are a part of critical infrastructure become unavailable, commercial and/or societal problems are inevitable. The issue of limiting...
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A novel approach exploiting properties of convolutional neural networks for vessel movement anomaly detection and classification
PublicationThe article concerns the automation of vessel movement anomaly detection for maritime and coastal traffic safety services. Deep Learning techniques, specifically Convolutional Neural Networks (CNNs), were used to solve this problem. Three variants of the datasets, containing samples of vessel traffic routes in relation to the prohibited area in the form of a grayscale image, were generated. 1458 convolutional neural networks with...
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Improving the Survivability of Carrier Networks to Large-Scale Disasters
PublicationThis chapter is dedicated to the description of methods aiming to improve the survivability of carrier networks to large-scale disasters. First, a disaster classification and associated risk analysis is described, and the disaster-aware submarine fibre-optic cable deployment is addressed aiming to minimize the expected costs in case of natural disasters. Then, the chapter addresses the improvement of the network connectivity resilience...
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SMART GRID TECHNOLOGIES IN ELECTRIC POWER SUPPLY SYSTEMS OF PUBLIC TRANSPORT
PublicationNowadays the issue of electric energy saving in public transport is becoming a key area of interest which is connected both with a growth in environmental awareness of the society and an increase in the prices of fuel and electricity. It can be achieved by improving the usage of regenerative breaking. In 2016 the Przedsiębiorstwo Komunikacji Trolejbusowej (PKT, Trolleybus Transport Company) in Gdynia began practical implementation...
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Neural modelling of dynamic systems with time delays based on an adjusted NEAT algorithm
PublicationA problem related to the development of an algorithm designed to find an architecture of artificial neural network used for black-box modelling of dynamic systems with time delays has been addressed in this paper. The proposed algorithm is based on a well-known NeuroEvolution of Augmenting Topologies (NEAT) algorithm. The NEAT algorithm has been adjusted by allowing additional connections within an artificial neural network and...
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Multi-task Video Enhancement for Dental Interventions
PublicationA microcamera firmly attached to a dental handpiece allows dentists to continuously monitor the progress of conservative dental procedures. Video enhancement in video-assisted dental interventions alleviates low-light, noise, blur, and camera handshakes that collectively degrade visual comfort. To this end, we introduce a novel deep network for multi-task video enhancement that enables macro-visualization of dental scenes. In particular,...
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Topology recognition and leader election in colored networks
PublicationTopology recognition and leader election are fundamental tasks in distributed computing in networks. The first of them requires each node to find a labeled isomorphic copy of the network, while the result of the second one consists in a single node adopting the label 1 (leader), with all other nodes adopting the label 0 and learning a path to the leader. We consider both these problems in networks whose nodes are equipped with...
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Energy and valuable organic products recovery from anaerobic processes
PublicationChapter 8 contains: Introduction, Energy balance in wastewater treatment plants and potential energy recovery, Potential valuable products recovery, Anaerobic processes focused on liquid products recovery; Anaerobic digestion (AD) processes focused on gaseous products recovery, Processes enhancing energy and valuable organic products recovery, Conclusions and perspectives. Anaerobic processes offer different pathways for the recovery...
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Analysis of economical lighting of highways in the environment of SMOL language
PublicationThe paper puts forward and implements a method of designing and creating a modelling simulation environment for eztensive and complete analysis of economical lighting on highways. From a general design viewpoint, the proposed solution explores the concept of a network description language (SMOL), which has been designed to describe the necessary network functions, mechanisms, and devices; for the purpose of their computer simulation...
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Multi-headed chimera states in coupled pendula
PublicationWe discuss the occurrence of the chimera states in the network of coupled, excited by the clock’s mechanisms pendula. We find the patterns of multi-headed chimera states in which pendula clustered in different heads behave differently (oscillate with different frequencies) and create different types of synchronous states (complete or phase synchronization). The mathematical model of the network shows that the observed chimera states...
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Quality of service in optical burst switched networks
PublicationIn the paper analytical models of two service differentiation schemes for optical burst switched network: extended offset time based and PPS (Preemptive Priority Scheme) are revised. Also accordance of analytical models for those schemes is studied when complete class isolation is assumed. Furthermore authors introduce an analytical model which describes an effective degree of isolation when burst switched network employs both...
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Quality of service in optical burst switched networks
PublicationIn the paper analytical models of two service differentiation schemes for optical burst switched network: extended offset time based and PPS (Preemptive Priority Scheme) are revised. Also accordance of analytical models for those schemes is studied when complete class isolation is assumed. Furthermore authors introduce an analytical model which describes an effective degree of isolation when burst switched network employs both...
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Routing decisions independent of queuing delays in broadband leo networks
PublicationThis paper presents an analysis of queuing and propagation delays of Inter-Satellite Links (ISLs) in broadband Low-Earth Orbit (LEO) satellite networks. It is shown that queuing delays are negligible in all reasonable working conditions of the broadband ISL network. This fact makes it possible to simplify the routing protocols in such networks and permits using already known multi-commodity flow solutions for routing. The performance...
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Methodology of Conformity Testing of VoIP Connections Scenarios for SIP Protocol
PublicationConformity and conformity testing have always had a crucial role in telecommunications. These issues are especially important in VoIP technology with SIP protocol as there are many hardware, software and service implementations. In this paper a methodology of automatic conformity testing of VoIP connections scenarios applying to any IP network is proposed. Example implementation of the methodology as Linux shell scripts is presented....
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TRAFFIC MODEL OF A MULTIDOMAIN IMS/NGN
PublicationIn this paper we continue our research and present an analytical traffic model of a multidomain Next Generation Network (NGN), which is standardized for delivering multimedia services based on the IP Multimedia Subsystem (IMS). The model takes into account several service scenarios (including registration, intra- and inter-operator calls) and a large set of network parameters. Using the model mean Call Set-up Delay and mean Call...
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Capacity analysis of the selected track system in partially ordered space
PublicationA proper location of the interval sections has significant impact on the traffic flow in the railway track network. This issue is critical during line modernization as well as when a new solution accounting for the traffic forecast at particular element of the railway track network is developed . However, the situation is more complex and more expensive for railway stations since improvement of the capacity requires critical organizational...
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An advanced tool integrating failure and sensitivity analysis into novel modeling of the stormwater flood volume
PublicationAn innovative tool for modeling the specific flood volume was presented that can be applied to assess the need for stormwater network modernization as well as for advanced flood risk assessment. Field measurements for a catchment area in Kielce, Poland, were used to apply the model and demonstrate its usefulness. This model extends the capability of recently developed statistical and machine learning hydrodynamic models developed...
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Gossiping by energy-constrained mobile agents in tree networks
PublicationEvery node of an edge-weighted tree network contains a data packet. At some nodes are placed mobile agents, each one possessing an amount of energy (not necessarily the same for all agents). While walking along the network, the agents spend the energy proportionally to the distance traveled and collect copies of the data packets present at the visited network nodes. An agent visiting a node deposits there copies of all currently...
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Images of LEGO bricks
Open Research DataThe set contains images of LEGO bricks (from multiple categories). The images were prepared for training neural network for recognition and labeling of LEGO bricks. The images contain one brick each. The images were taken from different sides by handheld camera hovering over the bricks lying on a white, non reflective surface.
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Number of bank branches per million inhabitants in EU countries 2015
Open Research DataAccording to the data presented, over the year (2016-2017), the network of bank branches in Poland decreased by over half a thousand (currently the total number of traditional bank branches, excluding partner branches, amounts to nearly 6 thousand). It is worth noting, however, that the number of bank branches per million inhabitants is the highest...
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Adam Przybyłek dr
PeopleAdam Przybyłek is an assistant professor at Gdansk University of Technology, Poland, where he has been working since October 2012. Between 2002 and 2011 he was a network consultant and instructor at Cisco Networking Academy. He obtained his Ph.D. degree in Software Engineering in 2011. He also holds a master's degree in Management Information Systems. His main research interests are in empirical software engineering with focus...
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Degradation kinetics and mechanism of pentoxifylline by ultraviolet activated peroxydisulfate
PublicationDegradation of pentoxifylline (PTX) by sodium peroxydisulfate (SPDS) assisted by UV irradiation has been investigated in deionized water. The treatment was more favorable over direct photolysis or peroxydisulfate oxidation alone. The effects of various parameters, including different dosage of oxidant agent, PTX concentration, initial solution pH levels, and the presence of inorganic ions like chloride, nitrate and carbonate have...
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Approximation of Message Inter-Arrival and Inter-Departure Time Distributions in IMS/NGN Architecture Using Phase-Type Distributions
PublicationCurrently it is assumed that requirements of the information society for delivering multimedia services will be satisfied by the Next Generation Network (NGN) architecture, which includes elements of the IP Multimedia Subsystem (IMS) solution. In order to guarantee Quality of Service (QoS), NGN has to be appropriately designed and dimensioned. Therefore, proper traffic models should be proposed and applied. This requires determination...
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Simulation model for evaluation of QoS routing algorithm in large packet networks
PublicationThe variety of traffic transferred via current telecommunication networks includes also voice, which should meet quality requirements. One of mechanisms, which can support QoS in current packet networks, is routing. There exist many routing proposals which should introduce the QoS into the network but practically they don't. Following paper presents the realization of simulation model for evaluation of a new routing algorithm DUMBRA...
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Visual Features for Improving Endoscopic Bleeding Detection Using Convolutional Neural Networks
PublicationThe presented paper investigates the problem of endoscopic bleeding detection in endoscopic videos in the form of a binary image classification task. A set of definitions of high-level visual features of endoscopic bleeding is introduced, which incorporates domain knowledge from the field. The high-level features are coupled with respective feature descriptors, enabling automatic capture of the features using image processing methods....
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Potential and Use of the Googlenet Ann for the Purposes of Inland Water Ships Classification
PublicationThis article presents an analysis of the possibilities of using the pre-degraded GoogLeNet artificial neural network to classify inland vessels. Inland water authorities monitor the intensity of the vessels via CCTV. Such classification seems to be an improvement in their statutory tasks. The automatic classification of the inland vessels from video recording is a one of the main objectives of the Automatic Ship Recognition and...
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South Coast Baltic Establishing durable cross-border boating destination management on the basis of the MARRIAGE cooperation network
ProjectsProject realized in Department of Management according to STHB.02.01.00-DE-0070/16-00 agreement from 2017-02-28
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Event driven MPC for networked control systems
PublicationBecause of variable delays and stochastic data packets loss networked control systems require suitable algorithms to ensure stability of the control system and guarantee desired control performance. This paper presents the idea of an event driven approach with MPC controller. In opposition to network compensation, where standard regulators are used, the presented solution integrates network with plant. A MPC based controller is...
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Long-distance quantum communication over noisy networks without long-time quantum memory
PublicationThe problem of sharing entanglement over large distances is crucial for implementations of quantum cryptography. A possible scheme for long-distance entanglement sharing and quantum communication exploits networks whose nodes share Einstein-Podolsky-Rosen (EPR) pairs. In Perseguers et al. [Phys. Rev. A 78, 062324 (2008)] the authors put forward an important isomorphism between storing quantum information in a dimension D and transmission...
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Detecting type of hearing loss with different AI classification methods: a performance review
PublicationHearing is one of the most crucial senses for all humans. It allows people to hear and connect with the environment, the people they can meet and the knowledge they need to live their lives to the fullest. Hearing loss can have a detrimental impact on a person's quality of life in a variety of ways, ranging from fewer educational and job opportunities due to impaired communication to social withdrawal in severe situations. Early...
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Soft Real-Time Communication with WebSocket and WebRTC Protocols Performance Analysis for Web-based Control Loops
PublicationThe web browser has become an access window for content and services. The browser is available on almost any device connected to the network, regardless of its intended use: desktop, mobile device, computing server, e-book reader etc. Browsers are used by people to read news, contact the world, to check a bank account, register a visit at the doctor, watching video content, electronic purchases, using web versions of the office...
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Parameters of land reference points in the Gdynia region and the Free-air anomaly grid of the South Baltic
Open Research DataThe data was registered during the campaign to verify the catalog value of the absolute point coordinates [point 5403 (POLREF-GORA DONAS)] of the national gravimetric control network. The data was recorded in two three-hour stationary measurement campaigns at the following points: Rozewie of the EUREF-POL network, Góra Donas POLREF, and mareograph points...
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Application of wavelength division multiplexing in sensor networks
PublicationOver the past few years the need to acquire data on various parameters from a number of sensors grew. The need that led to the development of a network of sensors which enables simultaneous control and measurement in a wide range of applications. The aim of this article is to discuss a possibility of connecting a variety of sensors in a network that would utilize WDM technology. Wavelength Division Multiplexing is commonly used...
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The Use of an Autoencoder in the Problem of Shepherding
PublicationThis paper refers to the problem of shepherding clusters of passive agents consisting of a large number of objects by a team of active agents. The problem of shepherding and the difficulties that arise with the increasing number of data describing the location of agents have been described. Several methods for reducing the dimensionality of data are presented. Selected autoencoding method using a Restricted Boltzmann Machine is...
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XPS investigations of tge tin/tin oxides - CNT composites
Open Research DataThe composite of tin/tin oxide nanoparticles with graphene oxide and CMC based on laser ablation technique as an electrode material for energy storage devices were manufactured. The material exhibited a three-dimensional conducting graphene oxide network decorated with tin or tin oxide nanoparticles. The presence of tin/tin oxide in composites was...
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Traffic Model of IMS/NGN Architecture with Transport Stratum Based on MPLS Technology
PublicationGrowing expectations for a fast access to information create strong demands for a universal telecommunication network architecture, which provides various services with strictly determined quality. Currently it is assumed that these requirements will be satisfied by Next Generation Network (NGN), which consists of two stratums and includes IP Multimedia Subsystem (IMS) elements. To guarantee Quality of Service (QoS) all NGN stratums...
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Call Processing Performance in a Multidomain IMS/NGN with Asymmetric Traffic
PublicationIn this paper we continue our research using the previously proposed analytical traffic model of a multidomain Next Generation Network (NGN), which is standardized for delivering multimedia services based on the IP Multimedia Subsystem (IMS). The aim of the model is to assess mean Call Set-up Delay (CSD) and mean Call Disengagement Delay (CDD), which are standardized call processing performance parameters. The output variables...
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Traffic model for evaluation of call processing performance parameters in IMS-based NGN
PublicationIn the modern world requirements for accurate and fast information distribution are becoming more and more important, which creates a strong necessity for appropriate telecommunication network architecture. Proposition of such an architecture is the Next Generation Network (NGN) concept, which in order to guarantee Quality of Service (QoS), should be correctly designed and dimensioned. For this reason proper traffic models must...
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Experimental test results of an automatic voltage regulator with independent phase voltage controllers
PublicationThe growing number of distributed renewable energy sources and dynamic constant-power loads (e.g. electric vehicle charging stations) pose new challenges for network operators. These changes result in alterations to network load profiles and load flows, leading to greater voltage volatility. One effective solution to these problems can be the use of automatic voltage regulators (AVRs), which stabilize and symmetrize voltage output,...
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Trust-Based Model for the Assessment of the Uncertainty of Measurements in Hybrid IoT Networks
PublicationThe aim of this paper is to introduce a NUT model (NUT: network-uncertainty-trust) that aids the decrease of the uncertainty of measurements in autonomous hybrid Internet of Things sensor networks. The problem of uncertainty in such networks is a consequence of various operating conditions and varied quality of measurement nodes, making statistical approach less successful. This paper presents a model for decreasing the uncertainty...
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Pose-Invariant Face Detection by Replacing Deep Neurons with Capsules for Thermal Imagery in Telemedicine
PublicationAbstract— The aim of this work was to examine the potential of thermal imaging as a cost-effective tool for convenient, non- intrusive remote monitoring of elderly people in different possible head orientations, without imposing specific behavior on users, e.g. looking toward the camera. Illumination and pose invariant head tracking is important for many medical applications as it can provide information, e.g. about vital signs, sensory...
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Optimum Choice of Randomly Oriented Carbon Nanotube Networks for UV-Assisted Gas Sensing Applications
PublicationWe investigated the noise and photoresponse characteristics of various optical transparencies of nanotube networks to identify an optimal randomly oriented network of carbon nanotube (CNT)-based devices for UV-assisted gas sensing applications. Our investigation reveals that all of the studied devices demonstrate negative photoconductivity upon exposure to UV light. Our studies confirm the effect of UV irradiation on the electrical...
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Genetic and Epigenetic Aspects of Atopic Dermatitis
PublicationAtopic dermatitis is a heterogeneous disease, in which the pathogenesis is associated with mutations in genes encoding epidermal structural proteins, barrier enzymes, and their inhibitors; the role of genes regulating innate and adaptive immune responses and environmental factors inducing the disease is also noted. Recent studies point to the key role of epigenetic changes in the development of the disease. Epigenetic modifications...
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Otwarte zasoby edukacyjne - przegląd inicjatyw w Polsce i na świecie
PublicationOtwarte zasoby edukacyjne (OZE) to materiały szkoleniowe oraz narzędzia wspierające zarówno uczenie, jak i nauczanie. Zjawisko to nierozerwalnie łączy się z szerszym pojęciem otwartej edukacji (OE), które postuluje zniesienie barier w nauczaniu tak, aby uczący się mogli zdobywać wiedzę zgodnie ze swoimi potrzebami edukacyjno-szkoleniowymi. Celem artykułu jest zapoznanie czytelników z zagadnieniem otwartych zasobów edukacyjnych,...
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WORK MOTIVATION PROFILES AND WORK PERFORMANCE IN A GROUP OF CORPORATE EMPLOYEES: A TWO-STEP CLUSTER ANALYSIS
PublicationFew studies have applied a person-centered approach to work motivation using cluster or profile analyses. Thus, little is known about which configurations of work motivations characterize professionals. The aim of this study is to establish the structure of work motivation profiles under the framework of self-determination theory and to examine the relationship between work motivation and subjective work performance. The study...
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Algoritmically improved microwave radar monitors breathing more acurrate than sensorized belt
PublicationThis paper describes a novel way to measure, process, analyze, and compare respiratory signals acquired by two types of devices: a wearable sensorized belt and a microwave radar-based sensor. Both devices provide breathing rate readouts. First, the background research is presented. Then, the underlying principles and working parameters of the microwave radar-based sensor, a contactless device for monitoring breathing, are described....