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Wyniki wyszukiwania dla: GENERALIZED CROSS-VALIDATION
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Existence of unbounded solutions to parabolic equations with functional dependence
PublikacjaThe Cauchy problem for nonlinear parabolic differential-functional equations is considered. Under natural generalized Lipschitz-type conditions with weights, the existence and uniqueness of unbounded solutions is obtained in three main cases: (i) the functional dependence u(·); (ii) the functional dependence u(·) and ∂xu(·); (iii) the functional dependence u(·)and the pointwise dependence ∂xu(t,x).
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Characteristics of the polarised off-body channel in indoor environments
PublikacjaThis paper addresses the depolarisation effect in off-body body area networks channels, based on measurements performed at 2.45 GHz in an indoor environment. Seven different scenarios, involving both static and dynamic users, were considered, taking a statistical perspective. The analysis of the cross-polarisation discrimination is performed, as well as the analysis of path loss in co- and cross-polarised channels. Results show...
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Periodic solutions of Lagrangian systems under small perturbations
PublikacjaIn this paper we prove the existence of mountain pass periodic solutions of a certain class of generalized Lagrangian systems under small perturbations. We show that the found periodic solutions converge to a periodic solution of the unperturbed system if the perturbation tends to 0. The proof requires to work in a rather unusual (mixed) Orlicz–Sobolev space setting, which bears several challenges.
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Low energy inelastic electron scattering from carbon monoxide: I. excitation of the a3Π, a’3Σ+ and AΠ1 electronic states.
PublikacjaDifferential scattering cross sections for electron excitation of the three lowest excited electron states of carbon monoxide are obtained experimentally using low-energy electron energy-loss spectroscopy and theoretically using the R-matrix method. The incident electron energies range from near-threshold of 6.3 eV to 20 eV. Experimental scattering angles range from 20◦ to 120◦. The normalization of the experimental cross sections...
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Theoretical and experimental study on scattering of low-energy electrons by dimethyl and diethyl ethers
PublikacjaWe report a joint theoretical and experimental investigation on low-energy electron scattering by dimethyl and diethyl ethers. The experimental elastic differential cross sections were measured at impact energies from 1 eV up to 30 eV and scattering angle range of 10◦ to 130◦. Theoretical elastic differential, integral and momentum-transfer cross sections are calculated at impact energies up to 30 eV, employing the Schwinger multichannel...
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Quality Assurance and Quality Control in the Analytical Chemical Laboratory. A practical approach : Second edition
PublikacjaThe second edition defines the tools used in QA/QC, especially the application of statistical tools during analytical data treatment. Clearly written and logically organized, it takes a generic approach applicable to any field of analysis. The authors begin with the theory behind quality control systems, then detail validation parameter measurements, the use of statistical tests, counting the margin of error, uncertainty estimation,...
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Thermal properties. DSC analysis of poly(xylitol sebacate-co-butylene sebacate) PXBS.
Dane BadawczeIn this work, a bio-based copolyester with good mechanical properties was synthesized andcharacterized in terms of structure, main properties and biodegradability Determining the chemicalstructure of such materials is important to understand their behavior and properties. Performingan extraction of insoluble cross-linked polymer using di erent solvents...
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Machine learning-based seismic fragility and seismic vulnerability assessment of reinforced concrete structures
PublikacjaMany studies have been performed to put quantifying uncertainties into the seismic risk assessment of reinforced concrete (RC) buildings. This paper provides a risk-assessment support tool for purpose of retrofitting and potential design strategies of RC buildings. Machine Learning (ML) algorithms were developed in Python software by innovative methods of hyperparameter optimization, such as halving search, grid search, random...
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Assessment of Electronic Sensing Techniques for the Rapid Identification of Alveolar Echinococcosis through Exhaled Breath Analysis
PublikacjaHere we present a proof-of-concept study showing the potential of a chemical gas sensors system to identify the patients with alveolar echinococcosis disease through exhaled breath analysis. The sensors system employed comprised an array of three commercial gas sensors and a custom gas sensor based on WO3 nanowires doped with gold nanoparticles, optimized for the measurement of common breath volatile organic compounds. The measurement...
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Magnetic Signature Description of Ellipsoid-Shape Vessel Using 3D Multi-Dipole Model Fitted on Cardinal Directions
PublikacjaThe article presents a continuation of the research on the 3D multi-dipole model applied to the reproduction of magnetic signatures of ferromagnetic objects. The model structure has been modified to improve its flexibility - model parameters determined by optimization can now be located in the cuboid contour representing the object's hull. To stiffen the model, the training dataset was expanded to data collected from all four cardinal...
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Electrical Tree Growth Behavior Under AC and DC High Voltage in Power Cables
PublikacjaThis work investigates the impact of an applied AC and DC high voltage on the electrical tree behavior in extruded cross-linked polyethylene (XLPE) insulation based on simulation and experimental validation. Extensive partial discharge (PD) testing methods are being implemented for high voltage cables under AC voltage for monitoring their condition. However, these PD testing methods cannot be utilized for power cables under DC...
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The viscometric evaluation of the gelation rate the chitosan-metal oxide hydrogel systems.
Dane BadawczeThe dataset shows the change in the viscosity of a hydrogel medium over time. Viscometric measurement was used as a universal method for determining the cross-linking rate of chitosan hydrogel using metal oxides or other solutions with a negative net charge. The method was prepared as a method of predicting the kinetics of additive manufacturing using...
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Green function diagonal for a class of heat equations
PublikacjaA construction of the heat kernel diagonal is considered as element of generalized zeta function theory, which gradient at the origin defines determinant of a differential operator in a technique for regularizing quadratic path integral. Some classes of explicit expressions of the Green function in the case of finite-gap potential coefficient of the heat equation are constructed. An algorithm and program for Mathematica are presented...
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Homoclinics for singular strong force Lagrangian systems
PublikacjaWe study the existence of homoclinic solutions for a class of generalized Lagrangian systems in the plane, with a C1-smooth potential with a single well of infinite depth at a point ξ and a unique strict global maximum 0 at the origin.Under a strong force condition around the singular point ξ, via minimization of an action integral, we will prove the existence of at least two geometrically distinct homoclinic solutions.
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Binary-Encounter Model for Direct Ionization of Molecules by Positron-Impact
PublikacjaWe introduce two models for the computation of direct ionization cross sections by positron impact over a wide range of collision energies. The models are based on the binary-encounter-Bethe model and take into account an extension of the Wannier theory. The cross sections computed with these models show good agreement with experimental data. The extensions improve the agreement between theory and experiment for collision energies...
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Multi-state multi-reference Møller-Plesset second-order perturbation theory for molecular calculations
PublikacjaThis work presents multi‐state multi‐reference Møller–Plesset second‐order perturbation theory as a variant of multi‐reference perturbation theory to treat electron correlation in molecules. An effective Hamiltonian is constructed from the first‐order wave operator to treat several strongly interacting electronic states simultaneously. The wave operator is obtained by solving the generalized Bloch equation within the first‐order...
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Electron interactions with Bis(pentamethylcyclopentadienyl) titanium(IV) dichloride and difluoride
PublikacjaWe present a combined experimental and theoretical study of the interaction of electrons with Bis(pentamethylcyclopentadienyl)titanium(IV) dichloride (Cp∗2TiCl2) and difluoride (Cp∗2TiF2). We report the experimental measurements of partial cross sections for the dissociative electron attachment (DEA) and the electron ionization (EI) mass spectra of isolated molecules. Estimates of the absolute cross sections are done on the basis...
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Measurement of the tram rail profile during a year of operation
Dane BadawczeThe aim of the work was to analyze the wear of rails during operation and to analyze the supplementation of heavy metals in the soil around the tram route, originating from wearing out rails and tram wheels.The dataset contains measurements of rail head coordinates in 9 research sections made in 8 measurement series. The wear of the rails in selected...
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Validated GC–MS method for determination of bisphenol a and its five analogues in dietary and nutritional supplements
PublikacjaBisphenol A (BPA) and its analogues showing structural and functional similarity to BPA are commonly applied in various industrial applications and thus are becoming ubiquitous in the environment. At the same time there is increasing scientific evidence that exposure to these chemicals may lead to adverse health effects in human and wildlife. In recent years dietary and nutritional supplements dedicated for athletes have become...
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Discrimination of Apple Liqueurs (Nalewka) Using a Voltammetric Electronic Tongue, UV-Vis and Raman Spectroscopy
PublikacjaThe capability of a phthalocyanine-based voltammetric electronic tongue to analyze strong alcoholic beverages has been evaluated and compared with the performance of spectroscopic techniques coupled to chemometrics. Nalewka Polish liqueurs prepared from five apple varieties have been used as a model of strong liqueurs. Principal Component Analysis has demonstrated that the best discrimination between liqueurs prepared from different...
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Structural and Thermo-Mechanical Properties of Poly(ε-caprolactone) Modified by Various Peroxide Initiators
PublikacjaThe modification of poly(ε-caprolactone) (PCL) was successfully conducted during reactive processing in the presence of dicumyl peroxide (DCP) or di-(2-tert-butyl-peroxyisopropyl)-benzene (BIB). The peroxide initiators were applied in the various amounts of 0.5 or 1.0 pbw (part by weight) into the PCL matrix. The effects of the initiator type and its concentration on the structure and mechanical and thermal properties of PCL were...
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Load Testing of GFRP Composite U-Shape Footbridge
PublikacjaThe paper presents the scope of load tests carried out on an innovative shell composite footbridge. The tested footbridge was manufactured in one production cycle and has no components made from materials other than GFRP laminates and PET foam. The load tests, performed on a 14-m long structure, were the final stage of a research program in the Fobridge project carried out in cooperation with: Gdańsk University of Technology (leader),...
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Low energy elastic scattering of electrons from hexafluoropropene (C3F6)
PublikacjaWe present cross sections from a joint experimental and theoretical study on elastic electron scattering from hexafluoropropene (C3F6) in the gas phase. The experimental results, using low energy electron spectroscopy, were obtained at incident electron energies of 0.5, 1, 1.5, 2, 3, 4, 5, 6, 10, 12, 15 and 20 eV, for scattering angles ranging from 10°to 130°. The theoretical method used in the computation of the integral, momentum...
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Digital Gaps and Economic Inequalities in MENA Countries: An Empirical Investigation
PublikacjaThis research contributes to the present state of the art by examining changes in cross-country inequalities in digital technologies deployment and economic performance. Our empirical target builds on the hypothesis that rapid global diffusion of digital technologies unequivocally leads to gradual eradication of cross-country digital gaps and cross-country inequalities in terms of deployment of ICT; the technology convergence occurs....
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SEM images of symmetrical cell interface with SrTi0.30Fe0.70O3-d electrode and CGO-20 substrate in function of sintering temperature
Dane BadawczeThis dataset contains images of polished cross section of symmetrical cell interface with SrTi0.30Fe0.70O3-d electrode and CGO-20 substrate in function of sintering temperature (800 °C, 900°C and 1000 °C) . Images were obtained using a PhenomXL (Thermo Fisher Scientific, the Netherlands) scanning electron microscope (SEM) with an accelerating voltage...
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SEM images of symmetrical cell interface with SrTi0.65Fe0.35O3-d electrode and CGO-20 substrate in function of sintering temperature
Dane BadawczeThis dataset contains images of polished cross section of symmetrical cell interface with SrTi0.65Fe0.35O3-d electrode and CGO-20 substrate in function of sintering temperature (800 °C, 900°C and 1000 °C) . Images were obtained using a PhenomXL (Thermo Fisher Scientific, the Netherlands) scanning electron microscope (SEM) with an accelerating voltage...
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SEM images of symmetrical cell interface with SrTi0.50Fe0.50O3-d electrode and CGO-20 substrate in function of sintering temperature
Dane BadawczeThis dataset contains images of polished cross section of symmetrical cell interface with SrTi0.50Fe0.50O3-d electrode and CGO-20 substrate in function of sintering temperature (800 °C, 900°C and 1000 °C) . Images were obtained using a PhenomXL (Thermo Fisher Scientific, the Netherlands) scanning electron microscope (SEM) with an accelerating voltage...
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SEM images of symmetrical cell interface with SrTi1-xFexO3-d electrodes and CGO-20 substrate sintered at 800 °C
Dane BadawczeThis dataset contains images of polished cross section of symmetrical cell interface with SrTi1-xFexO3-d (x=0.35; 0.50; 0..70) electrodes and CGO-20 substrate sintered at 800 °C. Images were obtained using a PhenomXL (Thermo Fisher Scientific, the Netherlands) scanning electron microscope (SEM) with an accelerating voltage of 12 kV in a high vacuum...
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60 GHz Microstrip Van Atta Arrays for Millimeter Wave Identification and Localization
PublikacjaIn this paper performance comparison of co-polarized and cross-polarized microstrip Van Atta arrays working in the 60 GHz frequency range is presented. They can be treated as simple chipless RFID tags with frequency response based identification. Tags with three different nominal resonance frequencies of 57, 62 and 67 GHz are designed by scaling optimized base model. Designed 62 GHz co-polarized and cross-polarized arrays with...
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Low energy inelastic electron scattering from carbon monoxide: II. Excitation of the b3Σ+, j3Σ+, B1Σ+, C1Σ+ and E1Π Rydberg electronic states
PublikacjaIn this second part of a two part paper (first part: Zawadzki et al (2020 J. Phys. B: At. Mol. Opt. Phys. 53 165201)) we present differential scattering cross sections for excitation of several Rydberg electronic states of carbon monoxide by electron impact. The first part concerned the low-lying valence states of CO. In the present study cross sections are obtained experimentally using low-energy electron energy-loss spectroscopy...
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Positron Scattering and Annihilation in Organic Molecules
PublikacjaIn this paper, we address the problem of connecting positron lifetimes in liquids with collision cross sections in gases. We present the analyses of annihilation lifetime spectra of positrons in the liquid benzene, c-hexane, n-hexane, methanol and ethanol and calculations of scattering cross sections of positrons with benzene and c-hexane in the gas phase.
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ZASTOSOWANIE MACIERZY PSEUDO ODWROTNEJ W METODACH ALOKACJI PĘDNIKÓW UKŁADU DYNAMICZNEGO POZYCJONOWANIA STATKU
PublikacjaUkłady kontroli alokacji pędników stanowią ważną część systemów dynamicznego pozycjonowania na statku. Określają one sygnały sterujące nastawami pędników, na podstawie uogólnionego wektora sił wzdłużnej, poprzecznej i momentu skręcającego, uzyskiwanych z prawa sterowania. W artykule przedstawiono wybrane algorytmy kontroli alokacji pędników, różniące się sposobem wyznaczania macierzy pseudo odwrotnej oraz algorytm bezpośredniej...
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Badania doświadczalne segmentu walidacyjnego kompozytowej kładki pieszo-rowerowej
PublikacjaW artykule przedstawiono zakres badań zrealizowanych na segmencie walidacyjnym o długości ~3 m będącym wycinkiem docelowej kompozytowej, powłokowej kładki pieszo-rowerowej. Wykonane testy statyczne i dynamiczne pozwoliły na ocenę pracy konstrukcji i potwierdziły przyjęte na etapie projektowania założenia teoretyczne.
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Analysis of Vibration and Acoustic Signals for Noncontact Measurement of Engine Rotation Speed
PublikacjaThe non-contact measurement of engine speed can be realized by analyzing engine vibration frequency. However, the vibration signal is distorted by harmonics and noise in the measurement. This paper presents a novel method for the measurement of engine rotation speed by using the cross-correlation of vibration and acoustic signals. This method can enhance the same frequency components in engine vibration and acoustic signal. After...
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Electron impact ionization and cationic fragmentation of the pyridazine molecules
PublikacjaElectron impact mass spectroscopy was used to investigate ionization and cationic fragmentation of the pyridazine (1,2 diazine), C4H4N2, molecules in the gas phase. The mass spectra were measured and the observed mass peaks assigned to the corresponding cations. The appearance energies of most of the cationic fragments were determined and the possible fragmentation processes are discussed. The total cross section for electron...
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Low-energy electron scattering from molecular hydrogen: Excitation of the X1Σg+ to b3Σu+ transition
PublikacjaWe present time-of-flight differential cross-section measurements and convergent close-coupling calculations of differential cross sections for the electron-impact excitation of the X 1 g + → b 3 u + transition in molecular hydrogen. A part of this work was recently published [M. Zawadzki et al., Phys. Rev. A 97, 050702(R) (2018)]. In this work, agreement between theory and experiment is excellent overall, and marks a transition...
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Characteristics of the Polarised Off-Body Channel in Indoor Environments
PublikacjaThis paper addresses the depolarisation effect in off-body Body Area Networks channels, based on measurements performed at 2.45 GHz in an indoor environment. Seven different scenarios, involving both static and dynamic users, were considered, taking a statistical perspective. The analysis of the cross-polarisation discrimination is performed, as well as the analysis of path loss in co- and cross-polarised channels. Results show...
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Marek Czachor prof. dr hab.
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Electron attachment to hexafluoropropylene oxide (HFPO)
PublikacjaWe probe the electron attachment in hexafluoropropylene oxide (HFPO), C3F6O, a gas widely used in plasma technologies. We determine the absolute electron attachment cross section using two completely different experimental approaches: (i) a crossed-beam experiment at single collision conditions (local pressures of 5 × 10−4 mbar) and (ii) a pulsed Townsend experiment at pressures of 20–100 mbar. In the latter method, the cross sections...
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Nonlinear FEM analysis of irregular shells composed of fiber metal laminates
PublikacjaThe paper deals with the analysis of failure initiation in shells made of Fiber Metal Laminates (FML). The elas-tic material law for orthotropic lamina is stated accounting for asymmetric in-plane stress and strain measures. The asymmetry results from the employed general nonlinear 6-field shell theory where the generalized dis-placements involve the translation and the proper rotation field. The novelty of the presented results...
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Domain Reduction in Hybrid Technique for Electromagnetic Wave Scattering Problems
PublikacjaThis paper proposes a combination of the field matching technique, finite element method and generalized impedance matrix, the main idea of which is to reduce the computational domain by surrounding a scatterer with the smallest convex shape and applying the field matching technique. This approach can be applied for arbitrary shaped scatterers and types of materials and allows for the reduction of the computational domain. In order...
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Structure and computationally-efficient simulation-driven design of compact UWB monopole antenna
PublikacjaIn this letter, a structure of a small ultra-wideband (UWB) monopole antenna, its design optimization procedure as well as experimental validation are presented. According to our approach, antenna compactness is achieved by means of a meander line for current path enlargement as well as the two parameterized slits providing additional degrees of freedom that help to ensure good impedance matching. For the sake of reliability, the...
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CUPPING DEFORMATION DURING DRYING OF BEECH WOOD (FAGUS SYLVATICA L.)
PublikacjaWood drying does not only consist in removing its moisture: the quality of the dried product is the main requirement for the industrial process. Because wood shrinks during drying, deformations and stresses develops than can lead to unusable product. When developing drying technologies and methods, the aim is to achieve the shortest possible drying times. The most common defects in wood after drying include cross warping (cup),...
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Maillard-reaction (glycation) of biopolymeric packaging films; principles, mechanisms, food applications
PublikacjaBackground The biodegradable, biocompatible, sustainable, and renewable nature of biomaterials has led to increased interest in developing biopolymeric food packaging films (BFPFs) with green ingredients and strategies. To enhance the performance of these films, biopolymer molecules can be modified or combined with additives like nanomaterials, cross-linkers, bioactive compounds, and other polymers, particularly with Maillard-reaction...
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Electron Scattering from Methyl Formate (HCOOCH3): A Joint Theoretical and Experimental Study
PublikacjaElastic low-energy electron collisions with methyl formate have been studied theoretically at the level of various theories. The elastic integral cross section was calculated using Schwinger multichannel and R-matrix methods, in the static-exchange and static-exchange plus polarization levels of approximations for energies up to 15 eV. The absolute total cross section for electron scattering from methyl formate has been measured...
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Kowalewo Pomorskie 2021 - video data - pedestrian, bicycles, vehicles
Dane BadawczeKowalewo Pomorskie 2021 - video data - pedestrian, bicycles, vehicles
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Attention-Based Deep Learning System for Classification of Breast Lesions—Multimodal, Weakly Supervised Approach
PublikacjaBreast cancer is the most frequent female cancer, with a considerable disease burden and high mortality. Early diagnosis with screening mammography might be facilitated by automated systems supported by deep learning artificial intelligence. We propose a model based on a weakly supervised Clustering-constrained Attention Multiple Instance Learning (CLAM) classifier able to train under data scarcity effectively. We used a private...
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Low-cost multiband compact branch-line coupler design using response features and automated EM model fidelity adjustment
PublikacjaDesign closure of compact microwave components is a challenging problem because of significant electromagnetic (EM) cross-couplings in densely arranged layouts. A separate issue is a large number of designable parameters resulting from replacement of conventional transmission line sections by compact microstrip resonant cells. This increases complexity of the design optimization problem and requires employment of expensive high-fidelity...
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Inverse Nonlinear Eigenvalue Problem Framework for the Synthesis of Coupled-Resonator Filters With Nonresonant Nodes and Arbitrary Frequency-Variant Reactive Couplings
PublikacjaA novel, general circuit-level description of coupledresonator microwave filters is introduced in this article. Unlike well-established coupling-matrix models based on frequency-invariant couplings or linear frequency-variant couplings (LFVCs), a model with arbitrary reactive frequencyvariant coupling (AFVC) networks is proposed. The engineered formulation is more general than prior-art ones—with the only restriction that the coupling...
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Numerical Investigation of Nuclear Reactor Kinetic and Heat Transfer Fractional Model with Temperature Feedback
PublikacjaAbstract—In the paper, the numerical results concerning the kinetics and proposed heat exchange models in nuclear reactor based on fractional calculus are presented for typical inputs. Two fractional models are proposed and compared with the model based on ordinary derivative. The first fractional model is based on one of the generalized Cattaneo equations. The second one is based on replacing the ordinary to fractional order of...