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Wyniki wyszukiwania dla: MICROFLUIDIC, FREQUENCY-RECONFIGURABLE, SELF-QUADRUPLEXING ANTENNA, SUBSTRATE-INTEGRATED WAVEGUIDE
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Novel MNZ-type microwave sensor for testing magnetodielectric materials
PublikacjaA novel microwave sensor with the mu-near-zero (MNZ) property is proposed for testing magnetodielectric material at 4.5 GHz. The sensor has a double-layer design consisting of a microstrip line and a metal strip with vias on layers 1 and 2, respectively. The proposed sensor can detect a unit change in relative permittivity and relative permeability with a difference in the operating frequency of 45 MHz and 78 MHz, respectively....
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The Concept of Using the Decision-Robustness Function in Integrated Navigation Systems
PublikacjaThe diversity and non-uniformity of the positioning systems available in maritime navigation systems often impede the watchkeeping officer in the selection of the appropriate positioning system, in particular, in restricted basins. Thus, it is necessary to introduce a mathematical apparatus to suggest, in an automated manner, which of the available systems should be used at the given moment of a sea trip. Proper selection of the...
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Greedy Multipoint Model-Order Reduction Technique for Fast Computation of Scattering Parameters of Electromagnetic Systems
PublikacjaThis paper attempts to develop a new automated multipoint model-order reduction (MOR) technique, based on matching moments of the system input–output function, which would be suited for fast and accurate computation of scattering parameters for electromagnetic (EM) systems over a wide frequency band. To this end, two questions are addressed. Firstly, the cost of the wideband reduced model generation is optimized by automating a...
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A Low-Cost System for Far-Field Non-Anechoic Measurements of Antenna Performance Figures
PublikacjaPrototype measurements are the key step in the development of antenna structures. Typically, their far-field characteristics are validated in expensive, dedicated facilities such as open range sites, or anechoic chambers. Despite being necessary for obtaining high-precision data (e.g., for device qualification), the use of costly infrastructure might not be fully justified when the main goal of measurements includes demonstration...
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Stormwater and snowmelt runoff storage control and flash flood hazard forecasting in the urbanized coastal basin.
PublikacjaCity of Gdańsk is located in a coastal region where changing climatic conditions increase the frequency of extreme weather events. Developing urbanization affects the hydrology of natural basins by simplification of the drainage system and reduction of infiltration and base flow. Consequently greater runoff rates flow into storm water collection systems, reservoirs and surrounding water bodies. Not only infrastructures of urban...
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Stormwater runoff in the urbanized coastal basin of Gdańsk Urbanized basin of Gdańsk
PublikacjaAnthropopressure strongly affects the primal water cycle. Alternation of the natural basins imposes changes of drainage patterns, reduction of bioretention, infiltration and base flow. As a result the overland flow predominates and greater runoff rates flow into storm water collection systems and reservoirs. Moreover changing climatic conditions increase the frequency of rapid extreme weather events. Infrastructures of urban areas...
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Rapid multi-objective design of integrated on-chip inductors by means of Pareto front exploration and design extrapolation
PublikacjaIdentification of the best trade-offs between conflicting design objectives allows for making educated design decisions as well as assessing suitability of a given component or circuit for a specific application. In case of inductors, the typical objectives include maximization of the quality factor and minimization of the layout area, as well as maintaining a required inductance at a given operating frequency. This work demonstrates...
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Analysis of electromagnetic disturbances in DC network of grid connected building-integrated photovoltaic system
PublikacjaThis paper focuses on conducted electromagnetic interference (EMI) emissions and propagation in the DC network of grid connected building integrated photovoltaic (PV) system. The investigated PV system, consists of ten solar panels, cabling and the grid-connected one phase inverter. The EMI simulation model of the real PV system has been developed with the aid of impedance analyzer measurements of solar panels and the DC network...
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Improving Output Performance of the Ultrasonic Multicell Piezoelectric Motor by Development the Multi-Rotor Structure
PublikacjaIn recent years, many researches have been carried out on piezoelectric multi-rotor structures. This paper describes the analysis, development and experimental process of an ultrasonic multi-cell piezoelectric motor using a multi-rotor structure. In this design, three independent cells have been integrated into a mechatronic system. Analytical model and finite element method are used for modal and dynamic analysis of the proposed...
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Dual-Polarized Wideband Bandpass Metasurface-Based Filter
PublikacjaThis paper presents a novel metasurface-based bandpass filter. The structure is realized by simply patterning a double-sided AD250 substrate, and does not require any vias or insertion of lumped elements. The top layer is an annular- aperture-array with multiple inner conductors, whereas the bottom layer is a first-order Hilbert-curve array. FEM-based simulation results of the filter are obtained using HFSS. The experimental validation...
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Ultrasonic wave propagation, digital image correlation and X-ray micro-computed tomography measurements of concrete during splitting (cube #3)
Dane BadawczeThe DataSet contains the results of the mechanical behaviour of a concrete cube under the splitting test. The cube had dimensions 70 x 70 x 70 cm3 and was made of concrete with the following ingredients: cement type CEM I 42.5R (330 kg/m3), water (165 kg/m3), aggregate 0/2 mm (710 kg/m3), aggregate 2/8 mm (664 kg/m3), aggregate 8/16 mm (500 kg/m3),...
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Ultrasonic wave propagation, digital image correlation and X-ray micro-computed tomography measurements of concrete during splitting (cube #1)
Dane BadawczeThe DataSet contains the results of the mechanical behaviour of a concrete cube under the splitting test. The cube had dimensions 70 x 70 x 70 cm3 and was made of concrete with the following ingredients: cement type CEM I 42.5R (330 kg/m3), water (165 kg/m3), aggregate 0/2 mm (710 kg/m3), aggregate 2/8 mm (664 kg/m3), aggregate 8/16 mm (500 kg/m3),...
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Ultrasonic wave propagation, digital image correlation and X-ray micro-computed tomography measurements of concrete during splitting (cube #4)
Dane BadawczeThe DataSet contains the results of the mechanical behaviour of a concrete cube under the splitting test. The cube had dimensions 70 x 70 x 70 cm3 and was made of concrete with the following ingredients: cement type CEM I 42.5R (330 kg/m3), water (165 kg/m3), aggregate 0/2 mm (710 kg/m3), aggregate 2/8 mm (664 kg/m3), aggregate 8/16 mm (500 kg/m3),...
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Ultrasonic wave propagation, digital image correlation and X-ray micro-computed tomography measurements of concrete during splitting (cube #2)
Dane BadawczeThe DataSet contains the results of the mechanical behaviour of a concrete cube under the splitting test. The cube had dimensions 70 x 70 x 70 cm3 and was made of concrete with the following ingredients: cement type CEM I 42.5R (330 kg/m3), water (165 kg/m3), aggregate 0/2 mm (710 kg/m3), aggregate 2/8 mm (664 kg/m3), aggregate 8/16 mm (500 kg/m3),...
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Modelling and Simulation of a New Variable Stiffness Holder for Milling of Flexible Details
PublikacjaModern industry expectations in terms of milling operations often demand the milling of the flexible details by using slender ball-end tools. This is a difficult task because of possible vibration occurrence. Due to existence of certain conditions (small depths of cutting, regeneration phenomena), cutting process may become unstable and self-excited chatter vibration may appear. Frequency of the chatter vibration is close to dominant...
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Biofilm bakteryjny uropatogennych szczepów E. coli Dr+ jako czynnik indukujący przewlekłość zakażeń dróg moczowych ograniczający ich leczenie
PublikacjaZakażenia dróg moczowych (ZUM) stanowią jedne z najczęściej występujących infekcji bakteryjnych, dotykających każdego roku miliony osób na świecie. Problematyka tych zakażeń wynika z ich przewlekłości i nawrotów, pomimo stosowania terapii antybiotykowej oraz ciągle wzrastającej lekooporności uropatogenów je wywołujących. Dominującym czynnikiem etiologicznym ZUM są uropatogenne szczepy E. coli (UPECs), wykazujące zdolność do adhezji,...
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Self-assembly of vertically oriented graphene nanostructures: multivariate characterisation by Minkowski functionals and fractal geometry
PublikacjaThe enormous self-assembly potential that graphene and its derived layered materials offer for responding to the contemporary environmental challenges has made it one of the most investigated materials. Hence, tuning its extraordinary properties and understanding the effect at all scales is crucial to tailoring highly customised electrodes. Vertically oriented graphene nanostructures, also known as carbon nanowalls (CNWs), due...
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Electromagnetic Simulation with 3D FEM for Design Automation in 5G Era
PublikacjaElectromagnetic simulation and electronic design automation (EDA) play an important role in the design of 5G antennas and radio chips. The simulation challenges include electromagnetic effects and long simulation time and this paper focuses on simulation software based on finite-element method (FEM). The state-of-the-art EDA software using novel computational techniques based on FEM can not only accelerate numerical analysis, but...
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Fading Modeling in Maritime Container Terminal Environments
PublikacjaIn this paper, an analytical model for slow and fast fading effects in maritime container terminals is derived, from fitting distributions to the results of measurements performed in an actual operational environment. The proposed model is composed of a set of equations, enabling to evaluate fading statistical distribution parameters for different system and environments conditions, as a function of frequency, base station antenna...
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Ni-based compounds in multiwalled graphitic shell for electrocatalytic oxygen evolution reactions
Dane BadawczeThis study investigates Ni-based compounds (Ni, NiO, Ni3C) coated with a graphitic shell as electrocatalysts for the oxygen evolution reaction (OER). Electron paramagnetic resonance (EPR) and X-ray diffraction (XRD) are employed to identify the presence and contribution of Nickel ions (Ni0, Ni2+, Ni3+) and determine the phase composition. Electrochemical...
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RF Input-Quasi-Reflectionless Dispersive-Delay Structures Based on Complementary-Diplexer Circuits
PublikacjaA class of RF dispersive-delay structures (DDSs) with input-quasi-reflectionless behavior is reported. It is based on the exploitation of complementary-diplexer circuit networks, in which the out-of-band RF-input-power echoes reflected by the main bandpass-filter-(BPF)-type channel are dissipated by the resistively-terminated auxiliary bandstop-filter-(BSF)-type channel. Specifically, it is shown that the influence of the absorptive...
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Broadband/Dual-band Metal-Mountable UHF RFID Tag Antennas: A Systematic Review. Taxonomy Analysis, Standards of Seamless RFID System Operation, Supporting IoT implementations, Recommendations and Future Directions
PublikacjaThe employment of broadband/dual-band ultra-high frequency (UHF) radio frequency identification (RFID) tag antennas contributes to the growth of RFID technology, with many potential implications, such as the increase of international trade, and reducing costs thereof. This study presents all reported articles on RFID tags for metal objects that can work seamlessly across different countries. Moreover, it addresses all available...
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Control of the bridge span vibration with high coefficient passive damper. Theoretical consideration and application
PublikacjaThe research was carried out due to the problem of vibration on the lively pedestrian drawbridge across the Motlawa River in the city of Gdansk. In the design stage, the main span of the footbridge showed unfavorable dynamic properties, which may create a comfort problem for pedestrians. The first vertical bending eigenfrequency was recognized as 1.64 Hz. The original design of the footbridge was equipped with a driving cylinder...
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Preliminary Results from the Removal of Phosphorus Compounds with Selected Sorption Material
PublikacjaDue to the resources of phosphorous are limited and are exhausted in the next 30 years the management of the resources is become current issue. Most of the phosphorus compounds is lost forever, because it is discharged with sewage into surface waters, causing eutrophication and in this way causing a further problem and challenge. On the other hand, there is a considerable need for phosphorus compounds, primarily in bioavailable...
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An Off-Body Narrowband and Ultra-Wide Band Channel Model for Body Area Networks in a Ferry Environment
PublikacjaIn the article an off-body narrowband and ultra-wide band channel model for Body Area Networks in a ferry environment is described. A mobile, heterogeneous measurement stand, that consists of three types of devices: miniaturized mobile nodes, stationary reference nodes and a data acquisition server was developed. A detailed analysis of both radio channels parameters in untypical indoor environment was carried out. An analysis of...
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A Low-Profile 3-D Printable Metastructure for Performance Improvement of Aperture Antennas
PublikacjaIn order to increase the radiation performance of aperture-type antennas, this paper demonstrates a low-profile, planar, single-layer, three-dimensional (3-D) printable metastructure. The proposed hybridized metastructure is highly transparent as it is made out of novel hybrid meta-atoms having transmission coefficient magnitudes greater than -0.72 dB and fully complies with the near-field phase transformation principle. The hybridized...
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Assessment of organic coating degradation via local impedance imaging
PublikacjaThe paper presents a new approach to organic coating condition evaluation at micrometer scale using localized impedance measurements. It is based on atomic force microscopy (AFM) in contact mode. Impedance is measured between conductive AFM tip and metal substrate covered with organic coating. A single-frequency voltage perturbation signal is applied between the electrodes and current response signal is registered. As the tip is...
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Surface diffusion and cluster formation of gold on the silicon (111)
PublikacjaPurpose: Investigation of the gold atoms behaviour on the surface of silicon by molecular dynamics simulation method. The studies were performed for the case of one, two and four atoms, as well as incomplete and complete filling of gold atoms on the silicon surface. Design/methodology/approach: Investigations were performed by the method of molecular dynamics simulation using the Large-scale Atomic/Molecular Massively Parallel...
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Deciphering the Molecular Mechanism of Substrate-Induced Assembly of Gold Nanocube Arrays toward an Accelerated Electrocatalytic Effect Employing Heterogeneous Diffusion Field Confinement
PublikacjaThe complex electrocatalytic performance of gold nanocubes (AuNCs) is the focus of this work. The faceted shapes of AuNCs and the individual assembly processes at the electrode surfaces define the heterogeneous conditions for the purpose of electrocatalytic processes. Topographic and electron imaging demonstrated slightly rounded AuNC (average of 38 nm) assemblies with sizes of ≤1 μm, where the dominating patterns are (111) and...
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On Improved-Reliability Design Optimization of High-Frequency Structures Using Local Search Algorithms
PublikacjaThe role of numerical optimization has been continuously growing in the design of high-frequency structures, including microwave and antenna components. At the same time, accurate evaluation of electrical characteristics necessitates full-wave electromagnetic (EM) analysis, which is CPU intensive, especially for complex systems. As rigorous optimization routines involve repetitive EM simulations, the associated cost may be significant....
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Noise and Electro-Ultrasonic Spectroscopy of Conducting PolymerThick Films
PublikacjaThick conducting films based on conducting polymer are characterized by DC conductivity and noise in temperature range 10 to 300 K. Conducting polymers could be used e.g. for the top electrode (cathode) in the solid tantalum or niobium capacitors. On the conducting polymer layer the top layer of carbon/graphite and/or silver polymer based pastes is applied in the capacitor technology. Our samples structure consists of conducting...
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Vibration Surveillance System with Variable Stiffness Holder for Milling Flexible Details
PublikacjaEfficient milling of the flexible details (i.e. rotor blades, thin-walled elements) using slender ball-end tools is a difficult task due to possibility of vibration occurrence. Because of the existence of certain conditions (small depths of cutting, regeneration phenomena), cutting process may lose stability and self-excited chatter vibration may appear. Frequency of the chatter vibration is close to dominant natural frequency...
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Soiling Effect Mitigation Obtained by Applying Transparent Thin-Films on Solar Panels: Comparison of Different Types of Coatings
PublikacjaDust accumulation on the front cover of solar panels is closely linked to location and orientation of photovoltaic (PV) installation. Its build-up depends on the module tilt angle, frequency of precipitation, humidity, wind strength and velocity, as well as grain size. Additionally, soil composition is determined by solar farm surroundings such as local factories, agricultural crops, and traffic. Over time, molecules of atmospheric...
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Detection of People Swimming in Water Reservoirs with the Use of Multimodal Imaging and Machine Learning
PublikacjaEvery year in many countries, there are fatal unintentional drownings in different water reservoirs like swimming pools, lakes, seas, or oceans. The existing threats of this type require creating a method that could automatically supervise such places to increase the safety of bathers. This work aimed to create methods and prototype solutions for detecting people bathing in water reservoirs using a multimodal imaging system and...
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Selection of material for infiltration of non-stoichiometric Sr0.95Ti0.3Fe0.7O3-δ
Dane BadawczeThe porous electrodes used for the infiltration were prepared from A-site non-stoichiometric Sr0.95Ti0.3Fe0.7O3-δ synthesized by the conventional solid state reaction method. Screen printed electrodes (0.5 cm2) on CGO-20 substrate, were fired at 800 °C for 2 hours in an air atmosphere. Infiltration of the scaffolds was performed by a water-based precursor...
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Ultrasonic wave propagation and digital image correlation measurements of polyolefin fibre-reinforced concrete beams under 3-point bending (beam B-002)
Dane BadawczeThe DataSet contains the results of the mechanical behaviour of a concrete beam under a 3-point bending test. The beams had dimensions 15 x 15 x 70 cm3. The beam B-Con was made of concrete without fibres (as the reference beam), while beams B-002, B-004, and B-006 were manufactured from the concrete mix containing 2 kg/m3, 4 kg/m3 and 6 kg/m3 of fibres,...
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Ultrasonic wave propagation and digital image correlation measurements of polyolefin fibre-reinforced concrete beams under 3-point bending (beam B-Con)
Dane BadawczeThe DataSet contains the results of the mechanical behaviour of a concrete beam under a 3-point bending test. The beams had dimensions 15 x 15 x 70 cm3. The beam B-Con was made of concrete without fibres (as the reference beam), while beams B-002, B-004, and B-006 were manufactured from the concrete mix containing 2 kg/m3, 4 kg/m3 and 6 kg/m3 of fibres,...
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Ultrasonic wave propagation and digital image correlation measurements of polyolefin fibre-reinforced concrete beams under 3-point bending (beam B-004)
Dane BadawczeThe DataSet contains the results of the mechanical behaviour of a concrete beam under a 3-point bending test. The beams had dimensions 15 x 15 x 70 cm3. The beam B-Con was made of concrete without fibres (as the reference beam), while beams B-002, B-004, and B-006 were manufactured from the concrete mix containing 2 kg/m3, 4 kg/m3 and 6 kg/m3 of fibres,...
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Ultrasonic wave propagation and digital image correlation measurements of polyolefin fibre-reinforced concrete beams under 3-point bending (beam B-006)
Dane BadawczeThe DataSet contains the results of the mechanical behaviour of a concrete beam under a 3-point bending test. The beams had dimensions 15 x 15 x 70 cm3. The beam B-Con was made of concrete without fibres (as the reference beam), while beams B-002, B-004, and B-006 were manufactured from the concrete mix containing 2 kg/m3, 4 kg/m3 and 6 kg/m3 of fibres,...
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Diagnosis of Damage in a Steel Tank Model by Shaking Table Harmonic Tests
PublikacjaDiagnosis of damage in civil engineering structures has recently become an important issue in the safety assessment procedure. Among a number of different approaches, a method of measuring the changes in natural frequencies is one of the most effective indicators of global damage. It has been successfully applied to relatively small. structures, however, the tests on large structures are very difficult and the practical application...
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Performance-driven yield optimization of high-frequency structures by kriging surrogates
PublikacjaUncertainty quantification is an important aspect of engineering design, as manufacturing toler-ances may affect the characteristics of the structure. Therefore, quantification of these effects is in-dispensable for adequate assessment of the design quality. Toward this end, statistical analysis is performed, for reliability reasons, using full-wave electromagnetic (EM) simulations. Still, the computational expenditures associated...
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A new approach to design of weather disruption-tolerant wireless mesh networks
PublikacjaWireless Mesh Networks, offering transmission rates of 1–10 Gb/s per a millimeter-wave link (utilizing the 71–86 GHz band) seem to be a promising alternative to fiber optic backbone metropolitan area networks because of significantly lower costs of deployment and maintenance. However, despite providing high transmission rates in good weather conditions, high-frequency wireless links are very susceptible to weather disruptions....
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A New Adaptive Method for the Extraction of Steel Design Structures from an Integrated Point Cloud
PublikacjaThe continuous and intensive development of measurement technologies for reality modelling with appropriate data processing algorithms is currently being observed. The most popular methods include remote sensing techniques based on reflected-light digital cameras, and on active methods in which the device emits a beam. This research paper presents the process of data integration from terrestrial laser scanning (TLS) and image data...
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Fully Tunable Analog Biquadratic Filter for Low-Power Auditory Signal Processing in CMOS Technologies
PublikacjaA novel Gm-C structure of a second-order continuous-time filter is proposed that allows for the independent control of the filter’s natural frequency (ω0) and quality factor (Q). The structure consists of two capacitors and four transconductors. Two transconductors together with the capacitors form a lossless second-order circuit with tunable ω0. The other two transconductors form a variable gain amplifier (VGA) which realizes...
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Overview of planar antenna loading metamaterials for gain performance enhancement: the two decades of progress
PublikacjaMetamaterials (MTMs) are artificially engineered materials with unique electromagnetic properties not occurring in natural materials. MTMs have gained considerable attention owing to their exotic electromagnetic characteristics such as negative permittivity and permeability, thereby a negative refraction index. These extraordinary properties enable many practical applications such as super-lenses, and cloaking technology, and are...
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Novel Versatile Topologies and Design Optimization of Wide-Bandstop Frequency Selective Surfaces for X-Band, Ku-Band and Millimeter-Wave Applications
PublikacjaNovel designs of frequency selective surface (FSS) are presented for wideband applications in X, Ku and mmWave (millimeter Wave) bands. Two identical metallic layers of FSS are imprinted on both sides of the RO4003 substrate. The geometry parameters are optimized to maximize the bandstop at the specified in-band maximum transmission level of –10 dB; satisfaction of the latter condition is enforced through appropriate formulation...
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Cost-Efficient Surrogate Modeling of High-Frequency Structures Using Nested Kriging with Automated Adjustment of Model Domain Lateral Dimensions
PublikacjaSurrogate models are becoming popular tools of choice in mitigating issues related to the excessive cost of electromagnetic (EM)-driven design of high-frequency structures. Among available techniques, approximation modeling is by far the most popular due to its versatility. In particular, the surrogates are exclusively based on the sampled simulation data with no need to involve engineering insight or problem-specific knowledge....
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Concept of an Innovative System for Dimensioning and Predicting Changes in the Coastal Zone Topography Using UAVs and USVs (4DBatMap System)
PublikacjaThis publication is aimed at developing a concept of an innovative system for dimensioning and predicting changes in the coastal zone topography using Unmanned Aerial Vehicles (UAVs) and Unmanned Surface Vehicles (USVs). The 4DBatMap system will consist of four components: 1. Measurement data acquisition module. Bathymetric and photogrammetric measurements will be carried out with a specific frequency in the coastal zone using...
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Implementation of Addition and Subtraction Operations in Multiple Precision Arithmetic
PublikacjaIn this paper, we present a digital circuit of arithmetic unit implementing addition and subtraction operations in multiple-precision arithmetic (MPA). This adder-subtractor unit is a part of MPA coprocessor supporting and offloading the central processing unit (CPU) in computations requiring precision higher than 32/64 bits. Although addition and subtraction operations of two n-digit numbers require O(n) operations, the efficient...
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Diagnosis of Damage in a Steel Tank with Self-Supported Roof through Numerical Analysis
PublikacjaThe safety of civil engineering structures is one of the most important issues of building industry. That is why the assessment of the damage-involved structural response has recently become of major concern to engineers. Among a number of different approaches to diagnosis of damage, the method of measuring the changes in natural frequencies is considered to be one of the most effective indicators of global damage. From the practical...