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Search results for: DISTANCE RELAY
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Problems of collisions between adjacent steel structures under earthquake excitation
PublicationNowadays, the high level of urbanization forces the designers to design closely-separated structures and to take into account many factors influencing the response of these structures, which may collide due to insufficient separation distance during moderate to strong ground motions. Recent observations as well as numerical and experimental investigations have confirmed that the interactions between structures may lead to significant...
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Performance analysis of an rfid-based 3d indoor positioning system combining scene analysis and neural network methods
PublicationThe main purpose of this research is to improve localization accuracy of an active Radio Frequency Identification, RFID tag, in 3D indoor space. The paper presents a new RFID based 3D Indoor Positioning System which shows performance improvement. The proposed positioning system combines two methods: the Scene Analysis technique and Artificial Neural Network. The results of both simulation using Log-Distance Path Loss Model and...
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The Niching Mechanism in the Evolutionary Method of Path Planning
PublicationThis paper presents the concept of the niching mechanism in the evolutionary method of path planning. The problem is considered based on the example of a ship path planning. In this method the diversity of individuals is tested in respect to their physical distance, not the fitness function value. The researches show that such an approach increases effectiveness of solution space exploration, what results in a final solution with...
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Studies of the mechanism of metal metal dusting of 10CrMo9-10 steel after 10 years of operation in trhe semi-regenerative catalytic reformer
PublicationThe study showed that metal dusting mechanism of 10CrMo9-10 steel operated in industrial environment differs from models developed in laboratories. Significant differences lie in the fact that the models developed in laboratories only assume the formation of metastable carbide M3C, while studies have shown that the formation of M3C carbides is associated with the transformation of primary carbides and in the next stage is preceded...
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The modyfication of the dynamic characteristics of vibratory conveyor
PublicationThe vibratory conveyors are used in the industry for continuous transportation of loose substances on distance up to 20meters. These conveyors are often suspended on expensive and massive frames, which are softly vibroisolated from the ground. As a result, they transfer significant dynamic forces on the ground. In case of 5 - 20 meter-long devices, the biggest construction problems are proper vibrations of the panel caused by bilateral...
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Application of Support Vector Machine for Determination of Impact of Traffic-Induced Vibrations on Buildings
PublicationThe aim of the article is to present an algorithm of Support Vector Machine created to forecast the impact of traffic-induced vibrations on residential buildings. The method is designed to classify the object into one of two classes. The classification into the first class means that there is no impact of vibrations on the building, while classification to the second class indicates the possible influence and suggests the execution...
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The Handling of Business Lawsuits by Common Courts in Poland: Identification of Transaction Costs
PublicationCelem artykułu jest identyfikacja czynników mających wpływ na koszty transakcyjne dochodzenia praw z umów pomiędzy przedsiębiorcami w sprawach gospodarczych. Na potrzeby artykułu przeprowadzono pilotażowe badanie 210 spraw sądowych zawisłych przed Sądem Okręgowym w Gdańsku w pierwszej instancji po 2009 r., w których wyrok wydano w 2012 r. (ostatnie 210 spraw) a od wyroku wniesiono apelację do Sądu Apelacyjnego w Gdańsku i zakończono...
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All solid state electrodes taste sensor with modified polymer membranes for discrimination of mineral water with different CO2 content
PublicationA potentiometric taste sensor with All Solid State Electrodes containing five all solid state electrodes with appropriate lipophilic compounds (benzyldimethyltetradecylammonium chloride, dodecyltrimethylammonium bromide, palmitic acid, stearic acid, and phytol) embedded in a polymer membrane was applied for discrimination of mineral water samples differed in CO2 content. Samples of still, slightly sparkling, and sparkling Naleczowianka...
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Using phase of short-term Fourier transform for evaluation of spectrogram performance
PublicationThe concept of spectrogram performance evaluation which exploits information on phase of short-term Fourier transform (STFT) is presented. A spectrograph which is time-frequency analyzing tool, is compared to a filter bank that demultiplexes a signal. Local group delay (LGD) and channelized instantaneous frequency (CIF) is obtained for each filtered component signal. In presented solution the performance is evaluated using so-called...
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Mathematical analysis of a generalised p53-Mdm2 protein gene expression model
PublicationWe propose the generalisation of the p53-Mdm2 protein gene expression model introduced by Monk (2003). We investigate the stability of a unique positive steady state and formulate conditions which guarantee the occurrence of the Hopf bifurcation. We show that oscillatory behaviour can be caused not only by time lag in protein transcription process, but also can be present in the model without time delay. Moreover, we investigate...
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Sensorless Control of Induction Motor Based on Super-Twisting Sliding Mode Observer With Speed Convergence Improvement
PublicationThe super twisting sliding-mode observer (ST-SMO) has been proposed to achieve an effective method for alleviating low-order harmonics of measured quantities, issues related to DC drift, and suppression of chattering due to low-frequency sampling. The conventional ST-SMO, on the other hand, suffers from control delay in the convergence trajectory due to the system disturbance, resulting in decreased anti-disturbance capability...
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Assessment of the Impact of GNSS Processing Strategies on the Long-Term Parameters of 20 Years IWV Time Series
PublicationAdvanced processing of collected global navigation satellite systems (GNSS) observations allows for the estimation of zenith tropospheric delay (ZTD), which in turn can be converted to the integrated water vapour (IWV). The proper estimation of GNSS IWV can be affected by the adopted GNSS processing strategy. To verify which of its elements cause deterioration and which improve the estimated GNSS IWV, we conducted eight reprocessings...
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Dynamic Route Discovery Using Modified Grasshopper Optimization Algorithm in Wireless Ad-Hoc Visible Light Communication Network
PublicationIn recent times, visible light communication is an emerging technology that supports high speed data communication for wireless communication systems. However, the performance of the visible light communication system is impaired by inter symbol interference, the time dispersive nature of the channel, and nonlinear features of the light emitting diode that significantly reduces the bit error rate performance. To address these problems,...
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Some variations of perfect graphs
PublicationWe consider (ψk−γk−1)-perfect graphs, i.e., graphs G for which ψk(H) =γk−1(H) for any induced subgraph H of G, where ψk and γk−1 are the k -path vertex cover number and the distance (k−1)-domination number, respectively. We study (ψk−γk−1)-perfect paths, cycles and complete graphs for k≥2. Moreover, we provide a complete characterisation of (ψ2−γ1)-perfect graphs describing the set of its forbidden induced subgraphs and providing...
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Theoretical study of highly-excited states of KRb molecule
PublicationSemi-empirical adiabatic potential energy curves of highly excited states of the KRb molecule are calculated as a function of the internuclear distance R over a wide range from 3 to 150 a0. The diatomic molecule is treated as an effective two-electron system by using the large core pseudopotentials and core polarization potentials. All calculations are performed by using the nonrelativistic CASSCF/MRCI method with accurate basis...
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Tonality Estimation and Frequency Tracking of Modulated Tonal Components
PublicationA novel method for tonality estimation and frequency tracking of tonal components modulated in frequency and amplitude is presented. The algorithm detects the local maxima of magnitude spectra corresponding to three contiguous frames of a signal and matches them into the tonal track candidates. The magnitude-based and phase-based methods are used to estimate the frequency jumps between spectrum maxima belonging to the tonal track...
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An Empirical Model for the Polarisation Characteristics of Indoor Off-Body Channels
PublicationThis paper presents an analysis of the polarisation characteristics for the channel in dynamic off-body communications, and an empirical channel model, based on measurements performed at 2.45 GHz in an office environment. Body presence and propagation conditions have a strong influence on signal depolarisation. The model assumes three components for the total path loss: mean path loss, represented by a log-distance function with...
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Wireless Charging Station Design for Electric Scooters: Case Study Analysis
PublicationThis study proposes an example of a wireless charging station design for a small-scale vehicle available on the market. The article analyzes basic transmitter inverter topologies and their compensation methods in terms of flexibility of control, tolerance to uncertainty in positioning, and the possibility of decreasing the integration price. Our comprehensive analysis focuses on the battery voltage range, energy capacity, cost,...
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Determinants of the surface quality, density and dimensional correctness in selective laser melting of the Ti-13Zr-13Nb alloy
PublicationSelective laser melting is widely used for custom-designed elements. Successful manufacturing depends on laser treatment parameters and material features. This research aimed to determine the effects of laser power, scan time and hatch distance on surface quality, relative density and dimensional precision for cuboids made of the Ti-13Zr-13Nb alloy. The influence of energy density, energy flux and pre-heating was seen to be decisive...
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TS-based RSM-aided design of cold-formed steel stiffened C-sectional columns susceptible to buckling
PublicationThe paper focuses on joint-performance analysis of a built-up cold-formed thin-walled C-sectional column with a fillister (stiffener) of the same type, interconnected with a series of bolts located along the length of the compressed members in specific spacing. The quantity of bolts and the non-connected starting distance of the fillister are considered random variables of the problem. Optimal distribution of joints on the stiffener...
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Quasi-analytical Near-to-Far Field Transformation Based on Field Matching Method for Scattering Problems
PublicationA new quasi-analytical near-to-far field transformation based on field matching method (field expansion in a base of Hankel functions) is presented. This approach uses finite element method to obtain near field, then the field is expressed in a base of Hankel functions. The evaluated coefficients allow to calculate the field outside the numerical domain, also in a far distance. The main advantage of the proposed technique is avoiding of...
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Modernity and postmodernity in architectural education
PublicationThe purpose of this article is to present a philosophical education strategy for architecture and interior architecture faculties. The approach is the result of trial and error in lectures and debates with students of philosophical courses in these fields. The presented article is not a result of empirical research, but rather a report on the problems encountered and proposals for their solution. The experience gained from conducting...
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Accuracy analysis of the RSSI BLE SensorTag signal for indoor localization purposes
PublicationIn this paper we describe possibility of use the RSSI signal (Radio Signal Strength Indication) from Texas Instruments SensorTag CC2650 for indoor positioning purposes. This idea is not a new but in our opinion it is possible to use SensorTags with Bluetooth LE wireless interface for positioning inside buildings in such applications as people findings in hospitals, senior come care, etc. RSSI is mostly selected as the sensor localization...
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Zastosowanie techniki ściegu odpuszczającego do spawania mokrego
PublicationW artykule przedstawiono zastosowanie techniki ściegu odpuszczającego do poprawy właściwości złączy ze stali konstrukcyjnych wykonywanych w warunkach mokrego spawania pod wodą. Scharakteryzowano spawanie mokre elektrodami otulonymi zmiany struktury i właściwości złączy spawanych przez nakładanie ściegów odpuszczających. Przedstawiono metodykę oraz wyniki badań metalograficznych i twardości próbek ze stali konstrukcyjnej o podwyższonej...
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Performance of a new commercial high-definition 3D patient specific quality assurance system for CyberKnife robotic radiotherapy and radiosurgery
PublicationConventional two dimensional and low-definition measurement techniques for dosimetric verification of radiotherapy treatment deliveries are no longer adequate in the era of hypofractionation and extremely high dose gradients. New quality assurance (QA) tools with 3D capability and high definition are urgently needed. The purpose of this study was to evaluate the performance of one of the first such commercial systems as applied...
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Automatic Identification System (AIS) Dynamic Data Integrity Monitoring and Trajectory Tracking Based on the Simultaneous Localization and Mapping (SLAM) Process Model
PublicationTo enhance the safety of marine navigation, one needs to consider the involvement of the automatic identification system (AIS), an existing system designed for ship-to-ship and shipto- shore communication. Previous research on the quality of AIS parameters revealed problems that the system experiences with sensor data exchange. In coastal areas, littoral AIS does not meet the expectations of operational continuity and system availability,...
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Solubility of carbon dioxide in water: Some useful results for hydrate nucleation
PublicationIn this paper, the solubility of carbon dioxide (CO2) in water along the isobar of 400 bar is determined by computer simulations using the well-known TIP4P/Ice force field for water and the TraPPE model for CO2. In particular, the solubility of CO2 in water when in contact with the CO2 liquid phase and the solubility of CO2 in water when in contact with the hydrate have been determined. The solubility of CO2 in a liquid–liquid...
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Validated HPTLC method for determination of ledol and alloaromadendrene in the essential oil fractions of Rhododendron tomentosum plants and in vitro cultures and bioautography for their activity screening
PublicationRhododendron tomentosum (Ledum palustre) is a bog shrub used in traditional medicine for treatment of respiratory and rheumatic diseases. Due to the large variability of the chemical composition of its essential oil, depending on the habitat, the in vitro cultures were established as the alternative source of the volatile fraction. There is a need to monitor a quality of the field grown as well as in vitro plant material, especially...
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Role of the Solvation Water in Remote Interactions of Hyperactive Antifreeze Proteins with the Surface of Ice
PublicationMost protein molecules do not adsorb onto ice, one of the exceptions being so-called antifreeze proteins. In this paper, we describe that there is a force pushing an antifreeze protein molecule away from the ice surface when it is not oriented with its ice-binding plane toward the ice and that this pushing force may be also present even when the protein is oriented with its ice-binding plane toward the ice. This force is absent...
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Performance Analysis and Quantification of BeiDou Navigation Satellite System (BDS-3)
PublicationPositioning, Navigation, and Timing (PNT) information play a vital role in everyday life of common persons. People greatly rely on Global Navigation Satellite System (GNSS)-enabled applications for navigation to reach their desired destination. However, GNSS navigation performance is highly degraded in urban environments due to the high probability of signal interruption, multipath (MP), and/or non-line-of-sight (NLOS) signal...
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Analysis of radiometric signal in sedimentating suspension flow in open channel
PublicationThe article discusses issues related to the estimation of the sedimentating solid particles average flow velocity in an open channel using radiometric methods. Due to the composition of the compound, which formed water and diatomite, received data have a very weak signal to noise ratio. In the process analysis the known determining of the solid phase transportation time delay the classical cross-correlation function is the most...
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A Point Set Connection Problem for Autonomous Mobile Robots in a Grid
PublicationConsider an orthogonal grid of streets and avenues in a Manhattan-like city populated by stationary sensor modules at some intersections and mobile robots that can serve as relays of information that the modules exchange, where both module-module and module-robot communication is limited to a straight line of sight within the grid. The robots are oblivious and move asynchronously. We present a distributed algorithm that, given...
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Observation value analysis - integral part of Bayesian diagnostics
PublicationDetailed subject of the research is to analyse the value of the observation, which is a part of preposterior analysis. For the presented network, the main objective was to determine, conducting of which of three tests is the most valuable from the perspective of determining possible need or possibility to omission expensive technical expertise. The main advantage of preposterior analysis is answering the question which of the considered...
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Using Wearable Electronics to Estimate Usefulness of Heart Rate Variability for Bathing Person Identif Cation
PublicationIn this paper the possibility of person identification based on biosignal is investigated. The work focus on the analysis of the changes in intervals between successive R-waves of electrocardiogram (ECG) recorded by wearable electronics in form of a necklaces. The main idea behind this project is to find efficient tool which may prevent sudden consciousness loss episodes or even sudden death episodes related to rapid temperature...
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Implementation of magnitude calculation of complex numbers using improved alpha max plus beta min algorithm
PublicationThe paper presents the hardware implementation of the improved alpha max plus beta min algorithm for calculating the magnitude of complex numbers. This version of the algorithm requires the general division which is performed using a noniterative multiplicative division algorithm. We analyze in detail the division algorithm, its error and the impact of finite word-length signal representations on the assumed total computation error....
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Optoelectronic system for investigation of cvd diamond/DLC layers growth
PublicationDevelopment of the optoelectronic system for non-invasive monitoring of diamond/DLC (Diamond-Like-Carbon) thin films growth during μPA ECR CVD (Microwave Plasma Assisted Electron Cyclotron Resonance Chemical Vapour Deposition) process is described. The system uses multi-point Optical Emission Spectroscopy (OES) and long-working-distance Raman spectroscopy. Dissociation of H2 molecules, excitation and ionization of hydrogen atoms...
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Proof of Concept of Indoor Location System Using Long RFID Readers and Passive Tags
PublicationThe paper proposes a system for persons and objects location with the use of long radio-frequency identifications (RFIDs) readers. In order to investigate all aspects of the proposed location system, several key elements had to be analyzed, including the distance from which the tagged objects and the possibility of using more than one tag within one RFID range at the same time. When designing the system, it is also necessary to...
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Asynchronous Method of Simultaneous Object Position and Orientation Estimation with Two Transmitters
PublicationThis paper proposes an object location method for all types of applications, including the Internet of Things. The proposed method enables estimations of the position and orientation of an object on a plane or in space, especially during motion, by means of location signals transmitted simultaneously from two transmitters placed on the object at a known distance from each other. A mathematical analysis of the proposed method and...
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System Loss Model for Body-to-Body Networks in Indoor and Outdoor Environments
PublicationA system loss model for body-to-body networks in indoor and outdoor environments is proposed in this paper, based on measurements taken at 2.45 GHz. The influence of the type of environment, antenna visibility and user mobility on model parameters has been investigated. A significant impact of mutual antennas’ placement and their visibility is shown. The proposed model fits well to empirical data, with the average root mean square...
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The dimensions of national competitiveness: the empirical analysis based on The World Economic Forum’s data
PublicationThe aim of this research is to determine the minimum number of uncorrelated dimensions which can describe national competitiveness (NC). NC is thought of as the ability of a nation to provide a conducive environment for its firms to prosper. It is shown that the environment affects national productivity catalytically through the interactions with the production factors while itself remaining unchanged. Selected World Economic...
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Numerical investigation on the performance of a small counter-rotating wind turbine
PublicationThe article presents the results of the investigation on the performance of a small counter-rotating wind turbine. The wind turbine has been simulated using Computational Fluid Dynamics methods. Actuator Line Model has been successfully used to represent rotors in the computational domain. A parametric study has been carried out, taking into account changes in the tip speed ratio of the rotors while maintaining a constant distance...
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Diagnostics of zno varistors by means of nondestructive testing
PublicationStandard industrial testing of high-voltage varistors for surge arresters demands application of high voltages and intensive currents. Nondestructive methods for varistor quality and endurance evaluation have been proposed and described. They rely on the application of resonant ultrasound spectroscopy, electro-ultrasonic spectroscopy, noise measurement and nonlinearity testing at voltages lower than continuous operating range....
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Hotspot of human verbal memory encoding in the left anterior prefrontal cortex
PublicationBackground: Treating memory and cognitive deficits requires knowledge about anatomical sites and neural activities to be targeted with particular therapies. Emerging technologies for local brain stimulation offer attractive therapeutic options but need to be applied to target specific neural activities, at distinct times, and in specific brain regions that are critical for memory formation. Methods: The areas that are critical...
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A novel method of time-frequency analysis: an essential spectrogram
PublicationA novel precise method of time-frequency analysis is presented. In the algorithm, a new energy distribution is estimated by simultaneously discard or displacement of the classical spec- trogram energy. A channelized instantaneous frequency and a local group delay are used in order to replacement in the same manner as formulated by Kodera et al. [1, 2]. Additionally, new representations: a channelized instantaneous bandwidth and...
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Usage of concentrated spectrogram for analysis of acoustical signals
PublicationA novel precise method of signal analysis in the time-frequency domain is presented. A signal energy distribution is estimated by discard and displacement of energy parts of the classical spectrogram. A channelized instantaneous frequency and a local group delay are used in order to energy replacement. Additionally, newly introduced representations such as: a channelized instantaneous bandwidth and a local group duration are used...
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Multipath routing for quality of service differentiation and network capacity optimization in broadband low-earth orbit systems
PublicationThis paper shows the importance of employing multiple different paths for routing in Inter-Satellite Link (ISL) networks in broadband Low-Earth Orbit (LEO) satellite systems. A theoretical analysis is presented and a routing concept is proposed to demonstrate three facts that make multipath routing especially important in broadband LEO networks: (1) differences in the propagation delays have a much greater impact on end-to-end...
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Simultaneous handover scheme for IEEE 802.11 WLANs with IEEE 802.21 tiggers
PublicationHandover performance in wireless networks is important, especially nowadays, when multimedia services are becoming increasingly available over the wireless devices. However, users expect uncompromised mobility when using the service. Thus, the support of multimedia services is not possible if handover is inefficient. At the same time it is clear that a strict separation between IP Layer and the Link Layer results in built-in sources...
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Time-frequency analysis of acoustic signals using concentrated spectrogram
PublicationThe paper presents improved method of time-frequency (TF) analysis of discrete-time signals. The method involves signal's local group delay (LGD) and channelized instantaneous frequency (CIF) to purposely redistribute all Short-time Fourier transform (STFT) lines. Additionally, the energy concentration index (ECI) and some histogram-like statistics are used to evaluate readability of estimated TF distributions of the energy. Recorded...
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On the lower smoothing bound in identification of time-varying systems
PublicationIn certain applications of nonstationary system identification the model-based decisions can be postponed, i.e. executed with a delay. This allows one to incorporate in the identification process not only the currently available information, but also a number of ''future'' data points. The resulting estimation schemes, which involve smoothing, are not causal. Assuming that the infinite observation history is available, the paper...
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Wideband Off-Body Channel Characteristics with Dynamic User
PublicationThis paper presents the preliminary results of a dynamic off-body channel characterisation study, based on wideband measurements at 5.8 GHz in an indoor environment. The Channel Impulse Response (CIR) was measured for a scenario with the user approaching and departing from the off-body antenna. A CIR deconvolution procedure was performed jointly in two polarisations, and the received signal power, Cross-Polarisation Discrimination...