Filtry
wszystkich: 744
wybranych: 668
Wyniki wyszukiwania dla: STOCHASTIC RESONANCE
-
Reliability and types of diagnosis in the process of diesel engine operation
PublikacjaThe article presents complexity of the problem concerning development of diagnosis with defined reliability by a diagnosing system (SDG) on technical condition of marine combustion engines, especially main engines. It was shown that development of the final diagnosis, the so-called initial operation diagnosis, on the operational usability (fDG on PEx) of a main engine in particular, is not possible without prior development of...
-
Assessing and Mitigating Ice-Jam Flood Hazards and Risks: A European Perspective
PublikacjaThe assessment and mapping of riverine flood hazards and risks is recognized by many countries as an important tool for characterizing floods and developing flood management plans. Often, however, these management plans give attention primarily to open-water floods, with ice-jam floods being mostly an afterthought once these plans have been drafted. In some Nordic regions, ice-jam floods can be more severe than open-water floods,...
-
Complex multidisciplinary optimization of turbine blading systems
PublikacjaThe paper describes the methods and results of direct optimization of turbine blading systems using a software package Opti_turb. The final shape of the blading is obtained from minimizing the objective function, which is the total energy loss of the stage, including the leaving energy. The current values of the objective function are found from 3D RANS computations (from a code FlowER) of geometries changed during the process...
-
Investigation of noises in the EPN weekly time series
PublikacjaThe constantly growing needs of permanent stati ons’ velocities users cause their stability level to increase. To this research we included more than 150 stations located across Europe operating within the EUREF Permanent Network (EPN) w ith weekly changes in the ITRF2005 reference frame. The obvious long-range dependencies in the stochastic part of GPS time series were p roven by Ljung-Box...
-
Dimensionality-Reduced Antenna Modeling with Stochastically Established Constrained Domain
PublikacjaOver the recent years, surrogate modeling methods have become increasingly widespread in the design of contemporary antenna systems. On the one hand, it is associated with a growing awareness of numerical optimization, instrumental in achieving high-performance structures. On the other hand, considerable computational expenses incurred by massive full-wave electromagnetic (EM) analyses, routinely employed as a major design tool,...
-
Miniaturized Dual-Band SIW-Based Bandpass Filters Using Open-Loop Ring Resonators
PublikacjaThis article presents two novel architectures of dual-band substrate integrated waveguide (SIW) bandpass filters (BPFs). Initially, two identical open-loop ring resonators (OLRRs) are coupled face-to-face on the top of the SIW cavity to realize a dual-band single-pole BPF. To obtain two-pole dual-band characteristics, two OLRRs resonant units are assembled horizontally within the top metal layer of the SIW, which is a technique...
-
Cost-efficient simulation-driven design of compact impedance matching transformers
PublikacjaIn this paper, an algorithmic framework for cost-efficient design optimization of miniaturized impedance matching transformers has been presented. Our approach exploits a bottom-up design that involves translating the overall design specifications for the circuit at hand to its elementary building blocks (here, compact microstrip resonant cells, CMRCs), as well as fast surrogate-assisted optimization of the cells followed by simulation-based...
-
A novel microstrip dual-layer rat-race coupler with compact size and enhanced bandwidth
PublikacjaMicrowave hybrid couplers are crucial components of mixers, phase shifters, amplifiers and other high-frequency systems. Conventional couplers are characterized by large size which limits their usefulness in modern applications. In this work, a novel compact rat-race coupler with enhanced bandwidth has been proposed. The structure consists of six compact microstrip resonant cells. It is implemented on two separate layers which permits...
-
Efficient analysis of structures with rotatable elements using model order reduction
PublikacjaThis paper presents a novel full-wave technique which allows for a fast 3D finite element analysis of waveguide structures containing rotatable tuning elements of arbitrary shapes. Rotation of these elements changes the resonant frequencies of the structure, which can be used in the tuning process to obtain the S-characteristics desired for the device. For fast commutations of the response as the tuning elements are rotated, the...
-
Accurate design of pseudoelliptic inline SIW filters with frequency-dependent couplings
PublikacjaThis paper presents an accurate synthesis method for inline SIW (Substrate Integrated Waveguide) generalized Chebyshev bandpass filters with frequency-dependent couplings. The technique is based on the synthesis of a coupling matrix that takes into account the impedance of the frequency-dependent stub. Thus, a loading effect compensation in adjacent resonators (via resonant frequency adjustment) and coupling elements (via coupling-value...
-
Collision Strengths of Astrophysical Interest for Multiply Charged Ions
PublikacjaThe electron impact excitation and ionization processes are crucial for modeling the spectra of different astrophysical objects, from atmospheres of late-type stars to remnants of supernovae and up to the light emission from neutron star mergers, to name just a few. Despite their signifi- cance, however, little is known quantitatively about these processes for low- and medium-impact energies of, say, Ekin . 5000 eV of the free...
-
Simulation-driven size-reduction-oriented design of multi-band antennas by means of response features
PublikacjaThis study addresses the problem of explicit size reduction of multi-band antennas by means of simulation-driven optimisation. The principal difficulty of electromagnetic (EM)-based miniaturisation of multi-band antennas is that several resonances have to be controlled independently (both in terms of their frequency allocation and depth) while attempting to reduce physical dimensions of the structure at hand. The design method...
-
O 1s excitation and ionization processes in the CO2 molecule studied via detection of low-energy fluorescence emission
PublikacjaOxygen 1s excitation and ionization processes in the CO2 molecule have been studied with dispersed and non-dispersed fluorescence spectroscopy as well as with the vacuum ultraviolet (VUV) photon-photoion coincidence technique. The intensity of the neutral O emission line at 845 nm shows particular sensitivity to core-to-Rydberg excitations and core-valence double excitations, while shape resonances are suppressed. In contrast,...
-
Edge-Guided Mode Performance and Applications in Nonreciprocal Millimeter-Wave Gyroelectric Components
PublikacjaThe analogies between the behavior of gyromagnetic and gyroelectric nonreciprocal structures, the use of the simple transfer matrix approach, and the edge-guided (EG) wave property, supported in a parallel plate model for integrated magnetized semiconductor waveguide, are investigated in those frequency regions, where the effective permittivity is negative or positive. As with their ferrite counterparts, the leakage of the EG waves...
-
Magnetic field mapping along a NV-rich nanodiamond-doped fiber
PublikacjaIntegration of NV−-rich diamond with optical fibers enables guiding quantum information on the spin state of the NV− color center. Diamond-functionalized optical fiber sensors have been demonstrated with impressive sub-nanotesla magnetic field sensitivities over localized magnetic field sources, but their potential for distributed sensing remains unexplored. The volumetric incorporation of diamonds into the optical fiber core allows...
-
Tailoring properties of indium tin oxide thin films for their work in both electrochemical and optical label-free sensing systems
PublikacjaThis work is devoted to the identification properties of indium tin oxide (ITO) thin films responsible for their possible application in combined optical and electrochemical label-free sensing systems offering enhanced functionalities. Since any post-processing would make it difficult to identify direct relation between deposition parameters and properties of the ITO films, especially when deposition on temperature-sensitive substrates...
-
Characterization of Bioactivity of Selective Molecules in Fruit Wines by FTIR and NMR Spectroscopies, Fluorescence and Docking Calculations
PublikacjaFourier transform infrared (FTIR) and proton nuclear magnetic resonance (1H NMR) spectroscopies were applied to characterize and compare the chemical shifts in the polyphenols’ regions of some fruit wines. The obtained results showed that FTIR spectra (1800–900 cm−1) and 1H NMR (δ 6.5–9.3 ppm) of different fruit wines can be used as main indices of the year of vintage and quality of fruit wines. In addition to the classical determination...
-
Exploring the landscape of automatic cerebral microbleed detection: A comprehensive review of algorithms, current trends, and future challenges
PublikacjaThis paper provides the first review to date which gathers, describes, and assesses, to the best of our knowledge, all available publications on automating cerebral microbleed (CMB) detection. It provides insights into the current state of the art and highlights the challenges and opportunities in this topic. By incorporating the best practices identified in this review, we established guidelines for the development of CMB detection...
-
A Comparability of Renal Length and Volume Measurements in MRI and Ultrasound in Children
PublikacjaIntroduction: Despite the significant increase in use of magnetic resonance imaging (MRI) in children, there is still a lack of normal reference values of renal size in this method and reference values are being interpolated from the ultrasound (US) studies. The study provides comparative analysis of agreement in renal length and volume measurements between MRI and ultrasound. Materials and Methods: Ninety-three children with a...
-
The effect of fishing basin construction on the behaviour of a footbrdge over the port channel
PublikacjaThe 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...
-
A Novel Cryptic Clostridial Peptide That Kills Bacteria by a Cell Membrane Permeabilization Mechanism
PublikacjaThis work reports detailed characteristics of the antimicrobial peptide Intestinalin (P30), which is derived from the LysC enzyme of Clostridium intestinale strain URNW. The peptide shows a broader antibacterial spectrum than the parental enzyme, showing potent antimicrobial activity against clinical strains of Gram-positive staphylococci and Gram-negative pathogens and causing between 3.04 ± 0.12 log kill for Pseudomonas aeruginosa...
-
Synthesis, structural characterization and reactivity of new trisubstituted N1-acylamidrazones: solid state and solution studies
PublikacjaA series of new linear trisubstituted N1-acylamidrazones have been investigated using a variety of analytical techniques and theoretical calculations to check the influence of the type of N1-acyl substituent on the resonance forms and conformational behavior in the solid state and in solution. The 1D- and 2D-NMR experiments, supported by computational studies, revealed that in solution all amidrazones exhibit conformational syn/anti...
-
Enhanced photocatalytic activity of accordion-like layered Ti3C2 (MXene) coupled with Fe-modified decahedral anatase particles exposing {1 0 1} and {0 0 1} facets
PublikacjaNew composites consisting of decahedral anatase particles exposing {001} and {101} facets coupled with accordion-like layered Ti3C2 with boosted photocatalytic activity towards phenol and carbamazepine degradation were investigated. The photocatalysts were characterized with X-ray diffraction (XRD), diffuse reflectance spectroscopy (DR/UV–Vis), Brunauer-Emmett-Teller (BET) specific surface area, Raman spectroscopy, scanning electron...
-
Modeling protein structures with the coarse-grained UNRES force field in the CASP14 experiment
PublikacjaThe UNited RESidue (UNRES) force field was tested in the 14th Community Wide Experiment on the Critical Assessment of Techniques for Protein Structure Prediction (CASP14), in which larger oligomeric and multimeric targets were present compared to previous editions. Three prediction modes were tested (i) ab initio (the UNRES group), (ii) contact-assisted (the UNRES- contact group), and (iii) template-assisted (the UNRES-template...
-
Segmentation Quality Refinement in Large-Scale Medical Image Dataset with Crowd-Sourced Annotations
PublikacjaDeployment of different techniques of deep learning including Convolutional Neural Networks (CNN) in image classification systems has accomplished outstanding results. However, the advantages and potential impact of such a system can be completely negated if it does not reach a target accuracy. To achieve high classification accuracy with low variance in medical image classification system, there is needed the large size of the...
-
Scheelite-Type Wide-Bandgap ABO4 Compounds (A = Ca, Sr, and Ba; B = Mo and W) as Potential Photocatalysts for Water Treatment
PublikacjaIn the present study, alkaline-earth metal scheelite-type compounds ABO4 (A = Ca, Sr, Ba, B = Mo, W) synthesized by a hydrothermal method were systematically studied. The as-obtained photocatalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer-Emmett-Teller surface area analysis (BET), UV–Vis diffuse reflectance spectroscopy (DR/UV-Vis), photoluminescence, and thermoluminescence (TL)...
-
Opto-Electrochemical Sensing Device Based on Long-Period Grating Coated with Boron-Doped Diamond Thin Film
PublikacjaThe fabrication process of thin boron-doped nanocrystalline diamond (B-NCD) microelectrodes on fused silica single mode optical fiber cladding has been investigated. The B-NCD films were deposited on the fibers using Microwave Plasma Assisted Chemical Vapor Deposition (MW PA CVD) at glass substrate temperature of 475 ºC. We have obtained homogenous, continuous and polycrystalline surface morphology with high sp3 content in B-NCD...
-
Nanocrystalline diamond microelectrode on fused silica optical fibers for electrochemical and optical sensing
PublikacjaFabrication process of thin boron-doped nanocrystalline diamond (B-NCD) microelectrode on fused silica single mode optical fiber has been investigated. The B-NCD films were deposited on the fibers using Microwave Plasma Assisted Chemical Vapor Deposition (MW PA CVD) at glass substrate temperature of 475 ºC. We have obtained homogenous, continuous and polycrystalline surface morphology with the mean grain size in the range of 100-250...
-
Subarachnoid Space: New Tricks by an Old Dog
PublikacjaPurpose: The purpose of the study was to: (1) evaluate the subarachnoid space (SAS) width and pial artery pulsation in both hemispheres, and (2) directly compare magnetic resonance imaging (MRI) to near-infrared transillumination/backscattering sounding (NIR-T/BSS) measurements of SAS width changes in healthy volunteers.Methods: The study was performed on three separate groups of volunteers, consisting in total of 62 subjects (33...
-
Structure and Molecular Dynamics in Renewable Polyamides from Dideoxy-Diamino Isohexide
PublikacjaThe chemical structure, the conformation, andthe flexibility of the polymer chain fragments present in thepolyamides synthesized from 2,5-diamino-2,5-dideoxy-1,4;3,6-dianhydrosorbitol, 1,4-diaminobutane, and either sebacic orbrassylic acid have been studied by liquid-state 2D NMRspectroscopy viz. correlation spectra (COSY) and heteronuclearmultiple-bond correlation spectra (gHMBC), by 13Ccross-polarization/magic-angle spinning...
-
Design and Optimization of Metamaterial-Based 5G Millimeter Wave Antenna for Gain Enhancement
PublikacjaIn this brief, a low profile, broadband, high-gain antenna array based on optimized metamaterials (MMs) with dual-beam radiation is reported for 5G millimeters wave (mm-wave) applications. The design is a simple bow tie operating at a 5G band of 28 GHz. It consists of two bow ties with substrate integrated waveguide (SIW)-based power splitter. A broad impedance bandwidth of 26.3−29.8 GHz is obtained by appropriately combining the...
-
Ultra-Wideband Vivaldi Antenna with an Integrated Noise-Rejecting Parasitic Notch Filter for Online Partial Discharge Detection
PublikacjaPower transformers and gas-insulated switchgear (GIS) play crucial roles in electrical power grids. However, they may suffer from degradation of insulation material due to wear and tear, leading to their imminent failure. Partial discharges (PDs) are an initial sign of insulation materials degradation which emit signals spanning various physical domains, including electromagnetic. PDs are temporally narrow, high-frequency, stochastic...
-
Sandwich Biobattery with Enzymatic Cathode and Zinc Anode Integrated with Sensor
PublikacjaCarbon paper covered with side-naphthylated multi walled carbon nanotubes was used as the conducting support for the construction of a biocathode in a hybrid biofuel cell. Laccase Carrena unicolor enzyme was employed as the catalyst for the 4e reduction of oxygen and a zinc disc covered with hopeite was used as the anode. Derivatized carbon nanotubes increase the working surface of the electrode and provide direct contact with...
-
Rectangular Waveguide Filters Based on Deformed Dual-Mode Cavity Resonators
PublikacjaIn this paper, a novel design for rectangular waveguide filters with deformed dual-mode (DM) cavity resonators is demonstrated. The new resonant cavity shape is a result of applying shape deformation to the basic rectangular cavity to enable its dual-mode operation. Internal coupling between the two orthogonal cavity modes is realized by geometry deformation, eliminating the need for additional coupling elements. The designs are...
-
Compact Substrate-Integrated Hexagonal Cavity-Backed Self-Hexaplexing Antenna for Sub-6 GHz Applications
PublikacjaA self-multiplexing SIW antenna based on hexagonal SIW cavity is proposed. The self-hexaplexing antenna consists of different sizes of resonating elements, which provide the hexaband operations. The antenna resonates at 5 GHz, 5.17 GHz, 5.32 GHz, 5.53 GHz, 5.62 GHz, and 5.72 GHz by employing different slot lengths between the resonating elements. The proposed antenna provides the individual tunable characteristics of the operating...
-
Design Evolution of the Ultrasonic Piezoelectric Motor Using Three Rotating Mode Actuators
PublikacjaThe development process and experimental investigation of the multicell piezoelectric motor is presented in this paper. The proposed design consists of three individual cells integrated into the stator, double rotor, and a preload system. Those elements are combined into a symmetrical structure of the motor. The two new prototypes have been designed, simulated and tested. Finite element numerical analysis is carried out to obtain...
-
Design and Experiments of a Piezoelectric Motor Using Three Rotating Mode Actuators
PublikacjaThis paper represents a numerical and experimental investigation of the multicell piezoelectric motor. The proposed design consists of three individual cells that are integrated into the stator, double rotor, and a preload system combined into a symmetrical structure of the motor. Each of the cells is characterized by a traveling wave and rotating mode motor. A finite element numerical analysis is carried out to obtain optimal...
-
Reactions of Lithiated Diphosphanes R2P−P(SiMe3)Li (R = tBu and iPr) with [MeNacnacTiCl2·THF] and [MeNacnacTiCl3]. Formation and Structure of TitaniumIII and TitaniumIV β‑Diketiminato Complexes Bearing the Side-on Phosphanylphosphido and Phosphanylphosphinidene Functionalities
Publikacjaβ-Diketiminate complexes of TiIII-containing phosphanylphosphido ligands [MeNacnacTi(Cl){η2-P(SiMe3)- PR2}] (MeNacnac− = [Ar]NC(Me)CHC(Me)N[Ar]; Ar = 2,6- iPr2C6H3) were prepared by reactions of [MeNacnacTiCl2· THF] with lithium derivatives of diphosphanes R2P−P(SiMe3) Li (R = tBu, iPr) in toluene solutions. Surprisingly, reactions of [MeNacnacTiCl2·THF] with R2P−P(SiMe3)Li in THF solutions led to TiIV complexes containing phosphanylphosphinidene ligands...
-
Joint experimental and theoretical study on electron scattering from titanium tetrachloride (TiCl4) molecule
PublikacjaAbsolute grand-total cross section for electron scattering from titanium tetrachloride, TiCl4, molecule was measured at electron-impact energies ranging from 0.3 to 300 eV, in the linear electron-transmission experiment. The elastic integral, differential, momentum transfer, and total ionization cross sections for TiCl4 molecule were also calculated for low and intermediate collisional energies at the level of various theories. The...
-
Communication: Inside the water wheel: Intrinsic differences between hydrated tetraphenylphosphonium and tetraphenylborate ions
PublikacjaTetraphenylphosphonium tetraphenylborate (TPTB) is a common reference electrolyte in physical chemistry of solutions allowing for a convenient partitioning of thermodynamic properties into single-ion contributions. Here, we compute on the basis of ab initio molecular dynamics simulations the infrared (IR) spectra for hydrated constituent ions of the TPTB assumption. Using spectral decomposition techniques, we extract important...
-
Hybrid Finite Element Method Development for Offshore Structures’ Calculation with the Implementation of Industry Standards
PublikacjaIn the design process of offshore steel structures, it is typical to employ commercial calculation codes in which simulation and evaluation of results are performed on the basis of the available standards (e.g. API, DNV, Lloyds). The modeling and solution rely on finite element methods and cover the simulation of the structure’s properties along with the influence of the marine environment – sea currents, wave and wind loading,...
-
Metamaterial-Based Sub-Microwave Electromagnetic Field Energy Harvesting System
PublikacjaThis paper presents the comprehensive analysis of the sub-microwave, radio frequency band resonant metastructures’ electromagnetic properties with a particular emphasis on the possibility of their application in energy harvesting systems. Selected structures based on representative topologies of metamaterials have been implemented in the simulation environment. The models have been analyzed and their substitute average electromagnetic...
-
An extended basis inexact shift–invert Lanczos for the efficient solution of large-scale generalized eigenproblems
PublikacjaThis paper proposes a technique, based on the Inexact Shift–Invert Lanczos (ISIL) method with Inexact Jacobi Orthogonal Component Correction (IJOCC) refinement, and a preconditioned conjugate-gradient (PCG) linear solver with multilevel preconditioner, for finding several eigenvalues for generalized symmetric eigenproblems. Several eigenvalues are found by constructing (with the ISIL process) an extended projection basis. Presented...
-
Optical emission spectroscopy of plasma generated by a waveguide-supplied microwave plasma source operated at 915MHz
PublikacjaIn this paper we present the results of an optical emission spectroscopic study of an atmospheric pressure microwave (915 MHz) nitrogen and nitrogen with carbon dioxide (1%) plasma at high working gas flow rate. This study was aimed at determining rotational Trot and vibrational Tvib temperatures of N+2 ions and N2, CN molecules. The plasma was generated in a waveguide-supplied cavity-resonant type microwave plasma source. All...
-
Efficient model order reduction for FEM analysis of waveguide structures and resonators
PublikacjaAn efficient model order reduction method for three-dimensional Finite Element Method (FEM) analysis of waveguide structures is proposed. The method is based on the Efficient Modal Order Reduction (ENOR) algorithm for creating macro-elements in cascaded subdomains. The resulting macro-elements are represented by very compact submatrices, leading to significant reduction of the overall number of unknowns. The efficiency of the model...
-
About definition of modes and magnetosonic heating in a plasma’s flow: Especial cases of perpendicular and nearly perpendicular wave vector and magnetic field
PublikacjaDynamics of hydrodynamic perturbations in a plasma depend strongly on an angle between the wave vector and equilibrium straight magnetic field. The case of perpendicular propagation is especial. There are only two (fast) magnetosonic modes since two (slow) ones degenerate into the stationary one with zero speed of propagation. This demands individual definition of wave modes by the links of hydrodynamic relations. These links are...
-
Thermally activated natural chalcopyrite for Fenton-like degradation of Rhodamine B: Catalyst characterization, performance evaluation, and catalytic mechanism
PublikacjaIn this work, catalytic activity of natural chalcopyrite (CuFeS2) was improved by thermal activation. The modified chalcopyrite was used as efficient catalyst for degradation of organic dye Rhodamine B (RhB) through advanced oxidation process (AOP). Effects of catalyst dosage, H2O2 concentration, reaction temperature, solution pH, anions, and natural organic matter on the degradation efficiency of RhB were investigated. This study...
-
Towards a method for detecting large roll motions suitable for oceangoing ships
PublikacjaThe concept of autonomous merchant ships is quite recent. The increasing interest in autonomous vessels is nowadays calling for smart technologies that are supposed to replace the human actions on board. This involves troublesome issues related to ship safety. In the future, decision-making processes that are conventionally performed by human beings on board ship will be moved ashore to the control centre and maybe even completely...
-
Data augmentation for improving deep learning in image classification problem
PublikacjaThese days deep learning is the fastest-growing field in the field of Machine Learning (ML) and Deep Neural Networks (DNN). Among many of DNN structures, the Convolutional Neural Networks (CNN) are currently the main tool used for the image analysis and classification purposes. Although great achievements and perspectives, deep neural networks and accompanying learning algorithms have some relevant challenges to tackle. In this...
-
Corrosion Inhibition Mechanism and Efficiency Differentiation of Dihydroxybenzene Isomers Towards Aluminum Alloy 5754 in Alkaline Media
PublikacjaThe selection of efficient corrosion inhibitors requires detailed knowledge regarding the interaction mechanism, which depends on the type and amount of functional groups within the inhibitor molecule. The position of functional groups between different isomers is often overlooked, but is no less important, since factors like steric hinderance may significantly affect the adsorption mechanism. In this study, we have presented how...