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Electrochemical cell impedance spectra at Eoc-200mV
Open Research DataThe dataset presents impedance spectrum of electrochemical cell filled with 3% NaCl solution presented in the figure below. This cell was used measured using Atlas-Sollich 0531 impedance analyser with built-in potentiostat. When changing the DC polarisation of the cell the non-linear phenomena could be observed. The impedance spectrum frequency range...
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Linear impedance of V2O5 nanorods obtained at 903K
Open Research DataThe DataSet contains the linear electrical properties of V2O5 nanorods which were measured by the impedance spectroscopy method. V2O5 nanorods were obtained by the sol-gel method. The information about xerogel powder synthesis is described in the Journal of Nanomaterials. The precursor powder was pressed into the disk-shaped pellets (12mm in diameter...
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The database of normal RR-intervals of length up to 512 of 41 patients at rest hospitalized due to the episode of acute ischemic stroke
Open Research DataThis dataset contains the data that was a basis for the results discussed in the paper “Persistent homology as a new method of the assessment of heart rate variability” by Grzegorz Graff, Beata Graff, Paweł Pilarczyk, Grzegorz Jabłoński, Dariusz Gąsecki, Krzysztof Narkiewicz, Plos One (2021), DOI: 10.1371/journal.pone.0253851.
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The database of normal RR-intervals of length up to 512 of 46 healthy subjects at rest
Open Research DataThis dataset contains the data that was a basis for the results discussed in the paper “Persistent homology as a new method of the assessment of heart rate variability” by Grzegorz Graff, Beata Graff, Paweł Pilarczyk, Grzegorz Jabłoński, Dariusz Gąsecki, Krzysztof Narkiewicz, Plos One (2021), DOI: 10.1371/journal.pone.0253851.
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Linear impedance of 0.5Si3N4–99.5(40Na2O-20CaO-40P2O5) glass measured with impedance spectroscopy method at low temperature region
Open Research DataThe linear electrical properties of 0.5Si3N4–99.5(40Na2O-20CaO-40P2O5) glass was measured by impedance spectroscopy method.
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Linear impedance of 40Na2O-20CaO-40P2O5 glass measured with impedance spectroscopy method at low temperature region
Open Research DataThe linear electrical properties of 40Na2O-20CaO-40P2O5 glass was measured by impedance spectroscopy method.
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Linear impedance of 25Na2O–20CaO–5P2O5–50SiO2 glass measured with impedance spectroscopy method at low temperature region
Open Research DataThe linear electrical properties of 25Na2O–20CaO–5P2O5–50SiO2 glass was measured by impedance spectroscopy method.
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Linear impedance of 1Si3N4–99(40Na2O-20CaO-40P2O5) glass measured with impedance spectroscopy method at low temperature region
Open Research DataThe linear electrical properties of 1Si3N4–99(40Na2O-20CaO-40P2O5) glass was measured by impedance spectroscopy method.
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Linear impedance of V2O5 nanorods obtained at 913K
Open Research DataThe DataSet contains the linear electrical properties of V2O5 nanorods which were measured by the impedance spectroscopy method. V2O5 nanorods were obtained by the sol-gel method. The information about xerogel powder synthesis is described in the Journal of Nanomaterials. The precursor powder was pressed into the disk-shaped pellets (12mm in diameter...
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Linear impedance of V2O5 nanorods obtained at 893K
Open Research DataThe DataSet contains the linear electrical properties of V2O5 nanorods which were measured by the impedance spectroscopy method. V2O5 nanorods were obtained by the sol-gel method. The information about xerogel powder synthesis is described in the Journal of Nanomaterials. The precursor powder was pressed into the disk-shaped pellets (12mm in diameter...
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PROJEKTOWANIE WIELOWYMIAROWEGO REGULATORA BACKSTEPPING W UKŁADZIE DYNAMICZNEGO POZYCJONOWANIA STATKU
PublicationW komercyjnych systemach dynamicznego pozycjonowania statku, pomimo znacznego wzrostu poziomu automatyzacji, wykorzystywane jest nadal sterowanie typu PID. Poprawę jakości procesu pozycjonowania może umożliwić wykorzystanie bardziej efektywnych algorytmów, oferujących zaawansowane nieliniowe techniki sterowania. W artykule przedstawiono zagadnienie projektowania regulatora pozycji i kursu dla układu dynamicznego pozycjonowania...
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Effect of shallow traps on admittance spectra of the system carrying SCLC and on values of charge carrier mobility extracted from susceptance
PublicationThe work concerns small-signal spectra of space-charge-limited current below threshold frequency (ft) of shallow traps. It is shown that below ft the small-signal concentration of trapped charge carriers is proportional to and in phase with small-signal concentration of free charge carriers, so there is no room for “slow shallow traps”. Conductance can be reduced by the traps, however no change in the range of real capacitance...
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Application of gpr method in diagnostics of reinforced concrete structures
PublicationThis paper presents an application of the ground penetration method (GPR) for diagnostics of reinforced concrete structures. In situ measurements were conducted for three civil engineering structures: the ground floor structure, the abutment of the railway viaduct and the concrete well. The dual polarized ground penetrating radar with the antenna operating at a center frequency of 2 GHz was used for GPR surveys. Three different...
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Synthesis and biological activity of ester derivatives of mycophenolic acid and acridines/acridones as potential immunosuppressive agents
PublicationImproved derivatives of mycophenolic acid (MPA) are necessary to reduce the frequency of adverse effects, this drug exerts in treated patients. In this study, MPA was coupled with N-(x-hydroxyalkyl)-9-acridone-4-carboxamides or N-(x-hydroxyalkyl)acridine-4-carboxamides to give respective ester conjugates upon Yamaguchi protocol. This esterification required protection of phenol group in MPA. Designed conjugates revealed higher...
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DYNWIR S-70 program for modal analysis of multisupported and multimass rotors
PublicationThe article provides a brief description of the program Dynwir-S-70 (currently being developed in the Rotor Dynamics and Slide Bearings Department in the Institute of Fluid-Flow Machinery Polish Academy of Sciences in Gdansk) which is a program for analysis of multi-supported and multi-mass rotors. Used algorithms and the construction of mass and stiffness matrix were presented. Damping matrix structure based on Rayleigh damping...
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Voltage Harmonic Distortion Measurement Issue in Smart-Grid Distribution System
PublicationThis paper presents the investigation results ofvoltage harmonic transfer accuracy problems through voltagetransformers which are widely used in power quality monitoringsystems in medium and high voltage grids. A simplified lumpedparameters circuit model of the voltage transformer is presentedand verified by simulation and experimental investigations. Anumber voltage transformers typically used in medium voltagegrid has been tested...
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Power electronic transformer based on cascaded H-bridge converter
PublicationIn this paper the control strategy of power electronic transformer (PET) is proposed. The analyzed structure of PET uses two seven-level cascaded H-bridge (CHB) rectifiers. The electrical power of PET is transferred between DC-links of CHB converters using dual-active-bridges (DABs) and low voltage high frequency transformers. The roposed solution allows for controlling the active and reactive power with a low level of harmonic...
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Efficiency of the Use of LTE System Radio Resources in Highway Transport Enironment
PublicationThe paper describes the problem of analysis of throughput-coverage characteristics of the LTE system. Simulation results of the efficiency of the use of LTE radio resources are presented. Simulation studies on the basis of original model of the LTE network simulator were carried out. In addition, the evaluation of throughput for a single connection, and available capacity were evaluated in the context of the use of the same...
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Microstructure and Dielectric Properties of Barium-vanadate Glasses
PublicationThe ac and dc conductivity in barium-vanadate glasses was investigated as a function of temperature and frequency with the use of impedance spectroscopy. The topography and microstructure of glasses were investigated by the means of X-ray diffraction (XRD) and scanning electron microscopy (SEM) methods. The XRD results show that all samples are amorphous but microscopy investigation reveals that glasses with greater amount of V2O5...
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Analysis of soundscape recordings in close proximity to the road in changeable wather conditions
PublicationThe acoustic vehicle sensing is the least invasive type of traffic detection. Also, acoustic-based vehicle detection technology is insensitive to precipitation and can operate in low light level. Therefore, this kind of method may be used for automatic detection of the vehicle passage events. It can also be employed for measurements of a vehicle speed and the vehicle assignment to the particular category. In this paper the results...
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Induction machine behavioral modeling for prediction of EMI propagation.
PublicationThis paper presents the results of wideband behavioral modeling of an induction machine (IM). The proposed solution enables modeling the IM differential- and common-mode impedance for a frequency range from 1 kHz to 10 MHz. Methods of parameter extraction are derived from the measured IM impedances. The developed models of 1.5 kW and 7.5 kW induction machines are designed using the Saber Sketch scheme editor and simulated in the...
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Diagnostics of high-voltage varistor quality using resonant ultrasound spectroscopy
PublicationResonant spectroscopy is an effective nondestructive testing method focused on defects detection in tested objects. Resonance spectrum contains an information about the mechanical properties and particularly about the structural homogeneity of the whole object. A swept frequency method has been used to measure the selected resonant frequencies range. The system for measurement of resonant ultrasound spectroscopy of high-voltage...
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Badanie jakości transmisji w interfejsie radiowym MC-CDMA
PublicationTechnika MC-CDMA (ang. Multi-Carrier Code Division Multiple Access) powstała z połączenia dwóch wcześniej stosowanych technik dostępu radiowego: CDMA (ang. Code Division Multiple Access) i OFDM (ang. Orthogonal Frequency-Division Multiplexing) i posiada zalety obu tych technologii. W referacie przedstawiona została budowa nadajnika i odbiornika dla tego interfejsu radiowego oraz wyniki badań symulacyjnych jakości transmisji w tym...
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Self-Optimizing Adaptive Vibration Controller
PublicationThis paper presents a new approach to rejection of sinusoidal disturbances acting at the output of a discrete-time linear stable plant with unknown dynamics. It is assumed that the frequency of the sinusoidal disturbance is known, and that the output signal is contaminated with wideband measurement noise. The proposed controller, called SONIC (self-optimizing narrowband interference canceller), combines the coefficient fixing technique,...
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Unités phraséologiques au pays de la traduction: transfert des collocations nomino-adjectivales avec le lexème «femme» dans la traduction de la littérature houellebecquienne du français vers l’italien et le polonais
PublicationThe present paper examines the transfer of nomino-adjectival collocations based on the word ‘femme’ (‘woman’) in the literary translation from French into Italian and Polish. The lexical connection analysed in the article can be defined as the habitual juxtaposition of a word with another word (or words) that has a significant frequency in a given language. The research corpus comprises seven Michel Houellebecq’s novels written...
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Software tool for modelling of mechatronic systems with elastic continua
PublicationThe paper presents a systematic computational package for modelling and analysis of complex systems composed of multiple lumped and distributed parameter subsystems. The constructed computer program enables the frequency domain analysis of a class of linear systems and to obtain reduced order model in the form of bond graph. Obtained modal bond graph can be directly exported into 20-Sim package to further processing including nonlinear...
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Microwave Ring Resonator Based Pressure Sensor
PublicationThis paper demonstrates a microwave pressure sensor, which is based on microstrip line-fed ring resonators. The first ring resonator is loaded with the concentric cylindrical shafts, while the same number of the hollow shanks as the shafts are mounted on the second ring resonator. The arrangement of the cylindrical shaft and hollow shank allows for mechanical movement between two substrates while maintaining electrical contact....
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Towards Audio Signal Equalization Based on Spectral Characteristics of a Listening Room and Music Content Reproduced
PublicationThis study presents investigations of the influence of the room acoustics on the frequency characteristic of the audio signal playback. First, the concept of a novel spectral equalization method of the room acoustic conditions is introduced. On the basis of the room spectral response, a system for room acoustics compensation based on an equalizer designed is proposed. The system settings depend on music genre recognized automatically....
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Wideband Modeling of DC-DC Buck Converter with GaN Transistors
PublicationThe general wideband modeling method of the power converter is presented on the example of DC-DC buck converter with GaN High Electron Mobility Transistors (HEMT). The models of all basic and parasitic components are briefly described. The two methods of Printed Circuit Board (PCB) layout parameter extraction are presented. The results of simulation in Saber@Sketch simulation software and measurements are compared. Next, the model...
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Remote Health Monitoring of Wind Turbines Employing Vibroacoustic Transducers and Autoencoders
PublicationImplementation of remote monitoring technology for real wind turbine structures designed to detect potential sources of failure is described. An innovative multi-axis contactless acoustic sensor measuring acoustic intensity as well as previously known accelerometers were used for this purpose. Signal processing methods were proposed, including feature extraction and data analysis. Two strategies were examined: Mel Frequency Cepstral...
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Analiza jakości transmisji treści audio-wideo w symulowanym łączu telekomunikacyjnym z wykorzystaniem techniki OFDM
PublicationWdrożenie niezawodnego systemu komunikacji audio-wideo przynosi wiele korzyści. Z uwagi na fakt, że ilość dostępnego pasma stale się kurczy, badacze koncentrują się na nowatorskich metodach transmisji. Obecnie technika OFDM (Orthogonal Frequency Division Multiplexing) jest szeroko stosowana zarówno w mediach przewodowych, jak i bezprzewodowych. W pracy przedstawiono badania jakości QoS (Quality of Service) symulowanego łącza transmisji...
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Subiektywny pomiar jakości programów radiowych strumieniowanych w sieci metodą crowdsourcingu
PublicationObecnie słuchacze mają dostęp do swoich ulubionych programów i audycji radiowych za pośrednictwem naziemnego standardu analogowego FM (Frequency Modulation) oraz cyfrowego DAB+ (Digital Audio Broadcasting plus). Należy podkreślić, że ten sam materiał nadawany jest jednocześnie w kilku technikach (tzw. simulcast), a znaczna większość rozgłośni udostępnia swoje programy także online. Niniejsza praca przedstawia wyniki badań dotyczących...
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Realizacja mobilnego urządzenia do wytwarzania kurtyny elektromagnetycznej do zastosowań specjalnych
PublicationIn the article the assumptions, design and realisation of the technological demonstrator of a mobile device for generating an electromagnetic curtain (AEGIS) were presented, both in the area of hardware and software. The device is designed to block radio communication by which it is possible to detonate the Radio Controlled Improvised Explosive Devices (RCIEDs). The preliminary laboratory tests of the demonstrator for generating...
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Open-Phase Fault Detection Method for Sensorless Five-Phase Induction Motor Drives with an Inverter Output Filter
PublicationThe paper presents the sensorless five-phase induction motor drive implementation with an inverter output filter with third harmonic injection. For the sensorless operation, the required observers are presented for the first and third harmonics with consideration of the inverter output filter. Moreover, the interaction of the observers and the control system is capable to handle a deactivation of one or two phases, which improves...
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Impact of high temperature drying process on beech wood containing tension wood
PublicationThe technology of high temperature drying has a great inuence on dimensional and selected physical changes in tension wood. Article is focused on the measurement properties such as moisture content, color changes and longitudinal warping. The quality of beech wood is determined based on structure and properties of wood, frequency of defects in wood material. The tension wood is considered as an important wood defect causing negative...
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Detection of damages in a rivetted plate
PublicationThe paper presents the results of damage detection in a riveted aluminium plate. The detection method has been based on Lamb wave propagation. The plate has been analysed numerically and experimentally. Numerical calculations have been carried out by the use of the time-domain spectral finite element method, while for the experimental analysis laser scanning Doppler vibrometry (LSDV) has been utilised. The panel has been excited...
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GPR simulations for diagnostics of a reinforced concrete beam
PublicationThe most popular technique for modelling of an electromagnetic field, the finite difference time domain (FDTD) method, has recently become a popular technique as an interpretation tool for ground penetrating radar (GPR) measurements. The aim of this study is to detect the size and the position of damage in a reinforced concrete beam using GPR maps. Numerical simulations were carried out using the finite differ-ence time domain...
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Low-cost 3D Printed Circularly Polarized Lens Antenna for 5.9 GHz V2X Applications
PublicationThis paper presents design and realization of a circularly polarized antenna consisting of a linearly polarized patch antenna and a 3D printed lens, at the same time performing the functions of wave collimator and a polarizer. The antenna is dedicated for 802.11p systems, as a part of road infrastructure, with operation bandwidth 5.85 - 5.925 GHz. Its realised gain and axial ratio at center frequency 5.9 GHz are 14.3 dBi and 2.17...
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Potential changes in an electric field and electrolytic corrosion.
PublicationSources have been described of corrosively hazardous electric fields and methods of determination of the corrosion hazard to metal structures caused by electrolytic corrosion. Results of potential and impedance investigations in the field of stray currents flowing out of a tram traction and in the presence of a defined electric field of low frequency have been presented. Uncertainties have been indicated relating to the generally...
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Układ bezpośredniej syntezy częstotliwości DDFS o obniżonym poborze mocy
PublicationW artykule zaprezentowano koncepcje układu bezpośredniej syntezy częstotliwości DDFS (ang. Direct Digital Frequency Synthesizer) opartego o aproksymację wielomianową. Układ zamiany fazy na sinus wykorzystuje jedynie analogowe funktory, tj. mnożniki oraz wzmacniacze operacyjne. Skutkuje to znaczącym obniżeniem poboru mocy oraz zmniejszeniem powierzchni układu w stosunku do rozwiązań wykorzystujących jedynie komponenty cyfrowe. Zastosowanie...
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The voltage on bus bars of the main switchboard of the ro-ro ship electrical power system during a layover at the port
Open Research DataThe dataset is part of the research results on the quality of supply voltage on bus bars of the main switchboard of the ship's electrical power system in different states of ship exploitation. The attached dataset contains the measurement results carried out onboard a ro-ro ship during a layover at the port.
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The voltage on bus bars of the main switchboard of the car carrier electrical power system at sea trials during a sea voyage
Open Research DataThe dataset is part of the research results on the quality of supply voltage on bus bars of the main switchboard of the ship's electrical power system in different states of ship exploitation. The attached dataset contains the measurement results conducted onboard the car carrier at sea trials. The data were recorded during a sea voyage, under normal...
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Nonlinear impedance of 58(2Bi2O3-V2O5)-42SrB4O7 glass heat-treated for 3 hours at 693 K, measured with impedance spectroscopy method at low temperature region
Open Research DataThe nonlinear electrcial properties of partially crystallized 58(2Bi2O3-V2O5)-42SrB4O7 glass was measured by impedance spectroscopy method.
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Nonlinear impedance of 58(2Bi2O3-V2O5)-42SrB4O7 glass heat-treated for 10 hours at 693 K, measured with impedance spectroscopy method at low temperature region
Open Research DataThe nonlinear electrcial properties of partially crystallized 58(2Bi2O3-V2O5)-42SrB4O7 glass was measured by impedance spectroscopy method.
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The effect of fishing basin construction on the behaviour of a footbrdge over the port channel
PublicationThe paper analyses possible causes of failure of the rotating footbridge over the Ustka port channel. In July, 2015, strange behaviour of this object was observed in the form of excessive vibrations of bridge platform suspension rods, with the accompanying acoustic effects. A preliminary geotechnical analysis has revealed that this destructive effect was caused by the nearby construction works, namely construction of a fishing...
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Detection of the Incoming Sound Direction Employing MEMS Microphones and the DSP
PublicationA 3D acoustic vector sensor based on MEMS microphones and its application to road traffic monitoring is presented in the paper. The sensor is constructed from three pairs of digital MEMS microphones, mounted on the orthogonal axes. Signals obtained from the microphones are used to compute sound intensity vectors in each direction. With this data, it is possible to compute the horizontal and vertical angle of an incoming sound....
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Series-Slot-Fed Circularly Polarized Multiple-Input-Multiple-Output Antenna Array Enabling Circular Polarization Diversity for 5G 28-GHz Indoor Applications
PublicationIn this paper, a four-element circularly polarized series-slot-fed multiple-input-multiple-output (MIMO) antenna array with circular polarization diversity is presented. The proposed design utilizes a combination of 45-degree inclined slots and a straight microstrip line feeding technique. The two antennas are designed to operate with the opposite sense of circular polarization (CP). CP is achieved by placing a patch of just about...
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Supervised-learning-based development of multi-bit RCS-reduced coding metasurfaces
PublicationCoding metasurfaces have been introduced as efficient tools allowing meticulous control over the electromagnetic (EM) scattering. One of their relevant application areas is radar cross section (RCS) reduction, which principally relies on the diffusion of impinging EM waves. Despite its significance, careful control of the scattering properties poses a serious challenge at the level of practical realization. This article is concerned...
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Low-Cost Yield-Driven Design of Antenna Structures Using Response-Variability Essential Directions and Parameter Space Reduction
PublicationQuantifying the effects of fabrication tolerances and uncertainties of other types is fundamental to improve antenna design immunity to limited accuracy of manufacturing procedures and technological spread of material parameters. This is of paramount importance especially for antenna design in the industrial context. Degradation of electrical and field properties due to geometry parameter deviations often manifests itself as, e.g.,...
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Measurement of Seafloor Acoustic Backscatter Angular Dependence at 150 kHz Using a Multibeam Echosounder
PublicationAcoustic seafloor measurements with multibeam echosounders (MBESs) are currently often used for submarine habitat mapping, but the MBESs are usually not acoustically calibrated for backscattering strength (BBS) and cannot be used to infer absolute seafloor angular dependence. We present a study outlining the calibration and showing absolute backscattering strength values measured at a frequency of 150 kHz at around 10–20 m water...