Filters
total: 734
filtered: 660
Search results for: STOCHASTIC RESONANCE
-
Sea-ice floe-size distribution in the context of spontaneous scaling emergence in stochastic systems
Publication -
QoS-sensitive selfish behavior in ad hoc wireless lans: a stochastic game model
PublicationRozważany jest prosty model stacji sieci bezprzewodowej wprowadzają-cych ruch elastyczny przy wymaganiu minimalnej przepływności. Każda stacja, okresowo przełączając się na egoistyczną konfigurację MAC, próbuje wyeliminować inne stacje z ubiegania się o pasmo sieci. Dla powstającej w ten sposób gry zastosowano model gry markowowskiej i pokazano istnienie symetrycznego punktu równowagi strategicznej.
-
QoS provisioning in a single-cell ad hoc WLAN via queuing and stochastic games
PublicationPokazano, że stosowanie agresywnych strategii dostępu do medium transmisyjnego może stanowić dla stacji sieci gwarancję równej szansy uzyskania pożądanej przepływności oraz zachowania jej na cały czas transferu danych. Przeprowadzono analizę gier typu stochastycznego pod kątem istnienia równowagi strategicznej przy założeniu probabilistycznych strategii dostępu.
-
Stochastic Integration and Long Term Predictor Estimation under Noisy Conditions for Speech Enhancement
Publication -
Spectral criterion for high-cycle fatigue of metals under multiaxial static and stochastic loading.
PublicationPraca dotyczy oceny zmęczenia metali ciągliwych w złożonych stanach wieloosiowych obciążeń statycznych i dynamicznych, przy założeniu, że składowe naprężenia są stacjonarnymi procesami stochastycznymi, które są stacjonarnie skorelowane i różniczkowalne w sensie średniokwadratowym. Przyjmując, że wartości średnie i gęstości widmowe mocy tych procesów są znane, sformułowano kryterium ograniczonej trwałości zmęczeniowej w dziedzinie...
-
Anisotropic stochastic dispersion model for large-eddy simulations of particle-laden turbulent flows
Publication -
Locally Adaptive Cooperative Kalman Smoothing and Its Application to Identification of Nonstationary Stochastic Systems
PublicationOne of the central problems of the stochastic approximation theory is the proper adjustment of the smoothing algorithm to the unknown, and possibly time-varying, rate and mode of variation of the estimated signals/parameters. In this paper we propose a novel locally adaptive parallel estimation scheme which can be used to solve the problem of fixed-interval Kalman smoothing in the presence of model uncertainty. The proposed solution...
-
The impact of methods the stochastic analysis on swimming safety of multihull floating units (Part 2)
PublicationIn part 2 the equations of the catamaran motion were divided into the system of two groups not conjugated with themselves containing the mutually conjugated equations. The feedback is obtained by the linear and nonlinear coefficients of dampening and coefficients of hydrostatic elasticity. The first group includes the symmetric movements (longitudinal movements), and the second group includes the antisymmetric movements (transverse)....
-
Adaptive stochastic and hybrid nonlinear optimization algorithms for improving the effectiveness of the biological processes at WWTP
PublicationWastewater treatment plays an important factor in the modern world. Insufficient treatment may result in environmental pollution which can further lead to disasters and diseases. However, processes that take place inside wastewater treatment plants (WWTP) are highly complex in nature, therefore it is difficult to design an efficient, optimal control system. The problem regarding biochemical reactions inside Sequential Batch Reactor...
-
Optical coherence tomography and magnetic resonance imaging visual pathway evaluation in Wolfram syndrome
Publication -
Effects of metallic silver particles on resonance energy transfer between fluorophores bound to DNA.
PublicationZbadano wpływ filmów wysepek metalicznego srebra na rezonansowe przekazywanie energii między fluoroforami związanymi z DNA. Donorem i akceptorem były odpowiednio 4´,6 diamidyno-2-fenylindon i jodek propydyny. Zmierzone dla tego układu czasy zaniku i widma fluorescencji pokazują, że sąsiedztwo cząstek srebra dramatycznie zwiększa promień Forstera, a tym samym i przekazywanie energii w znakowanym DNA.
-
Numerical Estimate of the Spectral Resonance Structure Frequency Scale of Natural ULF Magnetic Field
Publication -
Förster Resonance Energy Transfer-Activated Processes in Smart Nanotheranostics Fabricated in a Sustainable Manner
Publication -
Resonance Frequency Calculation of a Multilayer and Multipatch Spherical Microstrip Structure Using a Hybrid Technique
PublicationThis communication offers a rigorous analysis of the resonance frequency problem of a spherical microstrip structure mounted on a multilayer, dielectric-coated metallic sphere, with an electrically small radius. The structure consists of single or multiple metallic patches with arbitrary shapes. A full-wave analysis is employed with the use of proposed hybrid approach, combining the finite-difference technique with a spectral domain...
-
Spectral profiling of radicals in polymer degradation based on electron spin resonance imaging (ESRI)
Publication -
Case studies of resonance phenomena in high voltage overhead power lines with shunt reactors
PublicationMisguided design of the towers of power transmission lines can lead to serious problems such as voltage asymmetry, overvoltages, electric arc extinction difficulties or resonance – in case of double circuit line with shunt reactors. The paper points out those threats on example of 400 kV double circuit overhead transmission line with shunt reactors.
-
Comparison of resonance optical scattering of plane waves by infinite gratings of silver cylinders and strips
Publication -
Resonance microstrip structure with patch of arbitrary convex geometry with the use of field matching technique
PublicationAn analysis of the resonance frequency problem of planar microstrip structure with patch of arbitrary convex geometry is presented. A full-wave analysis is employed utilizing a combination of Galerkin’s moment method and field matching technique. In this approach, a field matching technique is adopted to calculate the patch surface current densities, and next the method of moments is utilized to calculate resonance frequencies...
-
Förster Resonance Energy Transfer and Trapping in Selected Systems: Analysis by Monte-Carlo Simulations
PublicationMetoda symulacji Monte Carlo została opisana i zastosowana jako efektywne narzędzie do analizy wyników pomiarów transferu energii w wybranych układach, dla których zastosowanie podejścia analitycznego jest ograniczone lub nawet niemożliwe. Pokazano, że symulacja Monte Carlo pozwala obliczyć tzw. czynnik orientacyjny dla układów częściowo uporządkowanych oraz szereg innych wielkości ważnych do opisu zjawiska transferu energii, które...
-
Buckling analysis of shell structures with stochastic imperfections using six parameter nonlinear shell theory
PublicationPrzedstawiono wpływ wstępnych losowych imperfekcji geometrycznych na wartość obciążenia krytycznego powłoki. W obliczeniach zastosowano autorski program MES wykorzystujący 6-cio parametrową nieliniową teorię powłok.
-
Investigations of the Methods of Time Delay Measurement of Stochastic Signals Using Cross-correlation with the Hilbert Transform
PublicationThe article presents the results of simulation studies of four methods of estimating time delay for random signals using cross-correlation with the Hilbert Transform. Selected models of mutually delayed stochastic signals were used in the simulations, corresponding to the signals obtained from scintillation detectors in radioisotope measurements of liquid-gas two-phase flow. Standard deviations of the values of the individual functions...
-
Stochastic optimisation algorithm for optimisation of controller parameters for control of dissolved oxygen in wastewater treatment plant
PublicationWastewater treatment plants (WWTPs) are very important facilities for mankind. They enable the removal and neutralisation of man-made pollutants. Therefore, it is important for wastewater treatment plants to operate as efficiently as possible so that the level of pollutants in the treated wastewater meets specific requirements. This paper concerns the design of a hierarchical nonlinear adaptive control system for dissolved oxygen...
-
Comparative analysis of numerical with optical soliton solutions of stochastic Gross–Pitaevskii equation in dispersive media
PublicationThis article deals with the stochastic Gross–Pitaevskii equation (SGPE) perturbed with multiplicative time noise. The numerical solutions of the governing model are carried out with the proposed stochastic non-standard finite difference (SNSFD) scheme. The stability of the scheme is proved by using the Von-Neumann criteria and the consistency is shown in the mean square sense. To seek exact solutions, we applied the Sardar subequation...
-
Stochastic FE-analysis of shear localization in 2D granular material within a micro-polar hypoplascity
PublicationW artykule przedstawiono wyniki numerycznej stochastycznej analizy wpływu rozkładu początkowego wskaźnika porowatości w materiałach granulowanych na powstawanie lokalizacji odkształceń. Obliczenia wykonano dla ścinania warstwy piasku stosując metodę elementów skończonych na bazie mikropolarnego prawa hipoplastycznego.
-
Resonant Conditions in a Node with an SVC Compensator
PublicationThe primary purpose of installing static shunt compensators in power grids is to improve the voltage conditions. Additional reactive power sources increase the system’s voltage stability and enable faster system recovery after a voltage failure. This paper presents the impact of an SVC device’s structure and settings on impedance change in the supply system, and hence on the frequencies at which resonance phenomena can develop.
-
Plasmon and structure resonances in the scattering of light by a periodic chain of silver nanocylinders
Publication -
Plasmon resonances of an infinite grating of silver wires coated with dielectric envelopes
Publication -
Surface plasmon resonance imaging biosensor for cathepsin G based on a potent inhibitor: Development and applications
Publication -
Effects of metallic silver particles on resonance energy transfer in label-led bovine serum albumin
PublicationZbadano wpływ cząstek metalicznego srebra na rezonansowe przekazywanie energii od wewnętrznych residów tryptofanowych w proteinie do zewnętrznie dowiązanego akceptora. W tych warunkach zaobserwowano istotny wzrost odległości Fórstera z 28,6 A do 63 A, co wskazuje na możliwość użycia cząstek srebra przy mierzeniu dużych odległości między molekułami i ich o przydatność w zastosowaniach biotechnologicznych.
-
Increased resonance energy transfer between fluorophores bound to DNA in proximity to metallic silver particles.
PublicationZbadano wpływ nanocząstek metalicznego srebra na rezonansowe przekazywanie energii między fluoroforami związanymi z DNA. Donor (pochodna kumaryny) i akceptor (Cy3) umieszczono na przeciwległych końcach DNA o strukturze podwójnej helisy i o 23 parach bazowych. W nieobecności cząstek srebra wydajność przekazywania energii w tym układzie wynosiła ok. 9%, zaś po umieszczeniu go między kwarcowymi płytkami pokrytymi filmem wysepek...
-
Susceptibility of the LLC Resonance Generator for Induction Heating on Changes in Load Parameters Caused by Heating the Charge
Publication -
First-order magnetic transition in single-crystalline CaFe2As2 detected by 75As nuclear magnetic resonance
PublicationPrzedstawione są wyniki badań jądrowego rezonansu magnetycznego na 75As dla kryształów CaFe2As2. Wyniki wskazują, że strukturalne i magnetyczne przejścia w CaFe2As2 są silnie skorelowane i są pierwszego rodzaju.
-
A Novel Ru(II) Polypyridine Black Dye Investigated by Resonance Raman Spectroscopy and TDDFT Calculations
PublicationThe optical properties of a new(bipyridine)2Ru(4H-imidazole) complex presenting a remarkablebroad absorption in the visible range are investigated. Thestrong overlap of the absorption with the solar radiationspectrum renders the studied complex promising as a blackabsorber and hence as a starting structure for applications inthe field of dye-sensitized solar cells. The correlations betweenstructural and electronic features for...
-
Electrochemical performance of indium-tin-oxide-coated lossy-mode resonance optical fiber sensor
PublicationAnalysis of liquids performed in multiple domain, e.g., optical and electrochemical (EC), has recently focus significant attention. Our previous works have shown that a simple device based on indium-tin-oxide (ITO) coated optical fiber core may be used for optical monitoring of EC processes. At satisfying optical properties and thickness of ITO a lossy-mode resonance (LMR) effect can be obtained and used for monitoring of optical...
-
Simultaneous optical and electrochemical label-free biosensing with ITO-coated lossy-mode resonance sensor
PublicationIn this work we discuss a new label-free biosensing device based on indium tin oxide (ITO) overlaid section of a multimode optical fiber fused silica core. The sensor has been used to optical measurements also simultaneously interrogated electrochemically (EC). Due to optimized thickness and optical properties of ITO film, a lossy-mode resonance (LMR) could be observed in the optical domain, where electrical properties of the film...
-
Influence of plasmon resonance on the luminescence of titanium dioxide thin films doped with rare earth ions
PublicationIn this work the study of the optical properties of europium doped titanium dioxide thin films (TiO2:Eu) enhanced by gold plasmonic nanostructures are presented. Plasmonic platforms were manufactured by thermal annealing of thin film of Au, deposited on a Corning glass substrate. As a result of thermal treatment, gold spherical nanostructures with average dimensions of 50 nm were obtained. Luminescent TiO2:Eu film was deposited...
-
PLC-based Implementation of Stochastic Optimization Method in the Form of Evolutionary Strategies for PID, LQR, and MPC Control
PublicationProgrammable logic controllers (PLCs) are usually equipped with only basic direct control algorithms like proportional-integral-derivative (PID). Modules included in engineering software running on a personal computer (PC) are usually used to tune controllers. In this article, an alternative approach is considered, i.e. the development of a stochastic optimizer based on the (μ,λ) evolution strategy (ES) in a PLC. For this purpose,...
-
A stochastic approach for the solution of single and multi – objective optimisation problems of biological processes in sequencing batch reactor
PublicationThis paper investigates the impact of implementing single and multi-optimisation solutions on the biological treatment process in a sequencing batch reactor (SBR). The research is based on a case study of the water resource recovery facility (WRRF) in Swarzewo, Northern Poland. The paper introduces the adaptive extremum seeking control (ESC) method for dissolved oxygen (DO) concentration control and places it in a layered control structure....
-
New approach to noncausal identification of nonstationary stochastic systems subject to both smooth and abrupt parameter changes
PublicationIn this paper we consider the problem of finiteintervalparameter smoothing for a class of nonstationary linearstochastic systems subject to both smooth and abrupt parameterchanges. The proposed parallel estimation scheme combines theestimates yielded by several exponentially weighted basis functionalgorithms. The resulting smoother automatically adjustsits smoothing bandwidth to the type and rate of nonstationarityof the identified...
-
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...
-
Modal FEM Analysis of Ferrite Resonant Structures
PublicationThe finite-element method (FEM) is applied for modal analysis of ferrite-loaded spherical resonators. To improve the efficiency of the numerical calculations, the body-of-revolution (BOR) technique is utilized. Due to the frequency-dependent ferrite permeability, FEM leads to a nonlinear eigenvalue problem that is challenging to solve. To this end, Beyn’s method is proposed. The effectiveness of the proposed approach is confirmed...
-
Resonance conditions for Mo93m isomer depletion via nuclear excitation by electron capture in a beam-based scenario
Publication -
Lateral diffusion coefficients in membranes measured by resonance energy transfer and a new algorithm for diffusion in two dimentions
PublicationOpisano wyniki pomiarów współczynników dyfuzji w membranach przy wykorzystaniu rezonansowego przekazywania energii wzbudzania. Donorem był kompleks metaloorganiczny renu o czasie życia ok. 3ćs, co pozwalało na pomiary współczynników dyfuzji mniejszych od 10 cm2/s. Zmierzono współczynniki dyfuzji w membranach typu DMPG i DOPC w różnych temperaturach.
-
Measuring Diffusion Coefficients of Nitroxide Radicals in Heterophasic Propylene−Ethylene Copolymers by Electron Spin Resonance Imaging
Publication -
Common methods for the chiral determination of amphetamine and related compounds II: Capillary electrophoresis and nuclear magnetic resonance
PublicationAmphetamine group and related ring-substituted substances are generally synthetic compounds, belonging to one of the most heavily abused drug groups in recent years. Some compounds in this class also originate from plants. Analysis of the enantiomers of AM-type compounds and metabolites is extremely important for a number of scientific disciplines. From studies of biological activity or mechanisms through determination of precursor...
-
Enhancing electrochemical properties of an ITO-coated lossy-mode resonance optical fiber sensor by electrodeposition of PEDOT:PSS
PublicationA sensor working in multiple domains may offer enhanced information about the properties of an investigated analyte, including those containing biological species. It has already been shown that a dual-domain sensing capability, i.e., in optical and electrochemical domains, can be offered by lossy-mode resonance (LMR) sensors based on indium-tin-oxide (ITO) thin film. The spectral response of the LMR sensors depends on the refractive...
-
An Assessment of RASSCF and TDDFT Energies and Gradients on an Organic Donor−Acceptor Dye Assisted by Resonance Raman Spectroscopy
PublicationThe excitation energies and gradients in the ground and the first excited state of a novel donor−(π- bridge)−acceptor 4-methoxy-1,3-thiazole-based chromophore were investigated by means of MS-RASPT2/RASSCF and TDDFT in solution. Within both methods, the excitation energies strongly depend on the employed equilibrium structures, whose differences can be rationalized in terms of bond length alternation indexes. It is shown that functionals with...
-
Nanodiamond phantoms mimicking human liver: perspective to calibration of T1 relaxation time in magnetic resonance imaging
PublicationPhantoms of biological tissues are materials that mimic the properties of real tissues. This study shows the development of phantoms with nanodiamond particles for calibration of T1 relaxation time in magnetic resonance imaging. Magnetic resonance imaging (MRI) is a commonly used and non-invasive method of detecting pathological changes inside the human body. Nevertheless, before a new MRI device is approved for use, it is necessary...
-
THE COMPOSITION MODULATION EFFECT IN GaInPAs SOLID SOLUTIONS AS A MANIFESTATION OF ENERGY RESONANCE AFTER MATERIAL'S SPINODAL DECOMPOSITION
PublicationThe Cahn-Hilliard model concepts are extended to describe the spinodal decomposition of Ga$_x$In$_{1-x}$P$_y$As$_{1-y}$ solid solutions grown on the InP substrate. The energy of elastic deformation of the thin layer of a solid solution was calculated on the assumption of its coherent conjugation with the massive InP substrate. The excess energy of component mixing in the solid phase was modeled in accordance with the simple solution...
-
Experimental tuning of AuAg nanoalloy plasmon resonances assisted by machine learning method
PublicationPlasmonic nanostructures based on AuAg nanoalloys were fabricated by thermal annealing of metallic films in an argon atmosphere. The nanoalloys were chosen because they can extend the wavelength range in which plasmon resonance occurs and thus allow the design of plasmonic platforms with the desired parameters. The influence of initial fabrication parameters and experimental conditions on the formation of nanostructures was investigated....