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Search results for: MINIATURIZED COUPLERS
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Implementation of Solute Transport in the Vadose Zone into the “HYDRUS Package for MODFLOW”
PublicationThe “HYDRUS package for MODFLOW” is an existing MODFLOW package that allows MODFLOW to simultaneously evaluate transient water flow in both unsaturated and saturated zones. The package is based on incorporating parts of the HYDRUS‐1D model (to simulate unsaturated water flow in the vadose zone) into MODFLOW (to simulate saturated groundwater flow). The coupled model is effective in addressing spatially variable saturated‐unsaturated...
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Superconducting properties and electronic structure of NaBi
PublicationResistivity, dc magnetization, and heat capacity measurements are reported for superconducting NaBi. Tc, the electronic contribution to the specific heat γ, the ΔCp/γTc ratio, and the Debye temperature are found to be 2.15 K, 3.4 mJ mol−1 K−2, 0.78, and 140 K respectively. The calculated electron–phonon coupling constant (λep = 0.62) implies that NaBi is a moderately coupled superconductor. The upper critical field and coherence...
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Systems, environments, and soliton rate equations: A non-Kolmogorovian framework for population dynamics
PublicationSoliton rate equations are based on non-Kolmogorovian models of probability and naturally include autocatalytic processes. The formalism is not widely known but has great unexplored potential for applications to systems interacting with environments. Beginning with links of contextuality to non- Kolmogorovity we introduce the general formalism of soliton rate equations and work out explicit examples of subsystems interacting with...
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New Generation of Water lubricated Foil bearing - Numerical Models and Experimental Verification
PublicationIn the paper a new idea of foil water lubricated bearing and methodology of hydrodynamic characteristics calculations is presented. To assesses the theoretical characteristics of these bearings two different computer models were built. First is structural model coupled with fluid model. It takes into account: fluid flow in the deformed fluid gap, specific design of bearing support and friction in bearing support. The second is...
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A Model-Order Reduction Approach for Electromagnetic Problems With Nonaffine Frequency Dependence
PublicationThe aim of this paper is to present a novel model-order reduction (MOR) technique for the efcient frequency-domain nite-element method (FEM) simulation of microwave components. It is based on the standard reduced-basis method, but the subsequent expansion frequency points are selected following the so-called sparsied greedy strategy. This feature makes it especially useful to perform a fast-frequency sweep of problems that lead...
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A universal method for the identification of genes encoding amatoxins and phallotoxins in poisonous mushrooms
PublicationABSTRACT Background. As the currently known diagnostic DNA targets amplified in the PCR assays for detection of poisonous mushrooms have their counterparts in edible species, there is a need to design PCR primers specific to the genes encoding amanitins and phallotoxins, which occur only in poisonous mushrooms. Objective. The aim of the study was testing of PCR-based method for detection of all genes encoding hepatotoxic cyclic...
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Fast surrogate-assisted frequency scaling of planar antennas with circular polarisation
PublicationIn this work, the problem of computationally efficient frequency scaling (re-design) of circular polarisation antennas is addressed using surrogate-assisted techniques. The task is challenging and requires the identification of the optimum geometry parameters to enable the operation of the re-designed structure at a selected (required) centre frequency. This involves handling several performance figures such as the antenna gain,...
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Reduced-cost optimization-based miniaturization of microwave passives by multi-resolution EM simulations for internet of things and space-limited applications
PublicationStringent performance specifications along with constraints imposed on physical dimensions, make the design of contemporary microwave components a truly onerous task. In recent years, the latter demand has been growing in importance, with the innovative application areas such as Internet of Things coming into play. The need to employ full-wave electromagnetic (EM) simu-lations for response evaluation, reliable yet CPU heavy, only...
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Electrochemical Activity of Electrode Material Consisting of Porous Copper and Silica Aerogel
PublicationElectrochemically obtained copper was combined with silica aerogel (SiO2ag). Obtained composite (SiO2@Cu/CuxOy) was tested as an electrode in contact with LiPF6 in EC/DMC electrolyte. The electrochemical measurements showed the presence of complex redox couple activities of SiO2@Cu/CuxOy. This experiment was employed to help in understanding the carbon role used as an electric contact for silica in Li-Ion batteries and clarify...
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Measurement method for capacitive sensors for microcontrollers based on a phase shifter
PublicationA complete measurement method dedicated to capacitive sensors has been developed. It includes the development of hardware (an analogue interface circuit for microcontrollers with built-in times/counters and analogue comparators) and software (a measurement procedure and a systematic error calibration (correction) algorithm which is based on a calibration dictionary). The interface circuit consists of a low-pass filter and a phase...
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HYBRID REDUCED MODEL OF ROTOR
PublicationIn the paper, the authors describe the method of model reduction of a rotor system. The proposed approach enables to obtain a low order model including e.g. nonproportional damping or the gyroscopic effect. This method is illustrated using the example of a rotor system. First, a model of the system was built without gyroscopic and damping effects by using the rigid finite element method. Next, this model was reduced. Finally, two...
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Gas boiler as a heat source for the domestic micro-CHP
PublicationThis analysis considers a commercially available domestic gas boiler as a heat source for a domestic organic Rankine cycle system. An experimental study was made into the applicability of the gas boiler (De Dietrich with thermal power 25 kW) coupled with the laboratory prototype micro ORC setup. The main aim of the study is to determine the working fluid temperature, attainable heat rates and effciencies of the whole system. Preliminary...
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Monitoring of volatile organic compounds (VOCs) in atmospheric air. Part I. On-line gas analyzers
PublicationThe paper reviews the subject literature concerning the analytical instruments routinely used for monitoring volatile organic compounds in atmospheric air. The analyzers are classified as stationary or mobile according to their ease of transport. Stationary DOAS (Differential Optical Absorption Spectroscopy) analyzer is characterized, as are MIMS (Membrane Introduction Mass Spectrometry), MESI (Membrane Extraction with Sorbent...
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Gas boiler as a heat source for the domestic micro-CHP
PublicationIn the presented analysis a commercially available domestic gas boiler as a heat source for domestic ORC is considered. The applicability of the gas boiler (De Dietrich with thermal power 25 kW) coupled with the laboratory prototype micro ORC setup has experimentally studied. The main aim of the study is to determine the working fluid temperature, attainable heat rates and efficiencies of the whole system. Preliminary investigations...
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A Numerical Model Study on Ice Boom in a Coastal Lake
PublicationA numerical study on the effectiveness of the proposed ice boom to be installed near the entrance of Lake Notoro, Hokkaido, Japan to prevent sea ice moving into the lake is presented. A two-dimensional hydro–ice dynamics model was modified to allow for the treatment of ice-boom interaction with the effect of tidal current. The numerical model is a coupled hydrodynamic and ice dynamic model. The ice dynamic component uses a Lagrangian...
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The use of HPLC-Q-TOF-MS for comprehensive screening of drugs and psychoactive substances in hair samples and several “legal highs” products
PublicationNon-targeted screening of drugs present in herbal products, known as “legal high” drugs and in hair as a biological matrix commonly used in toxicological investigations was accomplished with the use of high pressure liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (HPLC-Q-TOF-MS). In total, 25 and 14 therapeutical drugs and psychoactive substances/metabolites were detected in investigated hair samples...
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Stimulated by cyclodextrins high yield synthesis of azocrown analogues comprising pyrrole or imidazole residues
PublicationThe influence of cyclodextrins (CDs) on the formation of azocrown ethers comprising pyrrole, imidazole and substituted imidazole has been studied. Pyrrole, imidazole, 2-methyl-, 4-methyl- and 4-phenylimidazole were coupled with bisdiazonium salts derived from bis-1,5-(2-aminophenoxy)-3-oxapentane or bis-1,8-(2-aminophenoxy)-3,6-dioxaoctane to form macrocyclic compounds with two azo units. The syntheses were performed under standard...
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Badania podwójnego izolatora wykorzystujacego złącza ferrytowych sprzężonych linii mikropaskowych
PublicationW niniejszej pracy zbadano możliwości realizacji układu warstwowego izolatora podwójnego. Układ taki jest kaskadowym połączenie dwóch izolatorów wykonanych z cyrkulatorów FCL(Ferrite Coupled Line) zrealizowanych w technice linii mikropaskowych. W ramach przeprowadzonych badań wykonano projekty sekcji FCL oraz pozostałych układów tworzących układ izolatora, a następnie wyznaczono jego charakterystyki rozproszenia. Uzyskane numerycznie...
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A method of determination of electrical conduction mechanisms in complex amorphous materials
PublicationA novel approach to determine conduction mechanisms in complex amorphous materials was presented and tested on a real system. In the first step of the presented method, total electrical admittance of the material is analyzed in order to separate a couple of processes, each of which can be described by Jonscher's universal dielectric response. In the following step, a temperature dependence of dielectric response parameters of the...
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Discrete Green's function approach to disjoint domain simulations in 3D FDTD method
PublicationA discrete Green’s function (DGF) approach to couple 3D FDTD subdomains is developed. The total-field/scattered-field subdomains are simulated using the explicit FDTD method whilst interaction between them is computed as a convolution of the DGF with equivalent current sources measured over Huygens surfaces. In the developed method, the DGF waveforms are truncated using the Hann’s window. The error varies in the range -65 to -40...
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Globalized Knowledge-Based Simulation-Driven Antenna Miniaturization Using Domain-Confined Surrogates and Dimensionality Reduction
PublicationDesign of contemporary antenna systems encounters multifold challenges, one of which is a limited size. Compact antennas are indispensable for the new fields of application such as inter-net of things or 5G/6G mobile communication. Still, miniaturization generally undermines elec-trical and field performance. When attempted through numerical optimization, it turns into a constrained problem with costly constraints requiring electromagnetic...
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Simulations of flows in the coastal zone of the Baltic Sea
Open Research DataThe study area is located in the Southern Baltic, within Polish Marine Areas, adjacent to the coastline in the vicinity of Lubiatowo village, where The Coastal Research Station (CRS) – a field laboratory of the Institute of Hydro-Engineering of the Polish Academy of Sciences (IBW PAN) –is situated. The numerical reconstruction of the coastal flow was...
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Local-Global Space Mapping for Rapid EM-Driven Design of Compact RF Structures
PublicationIn this work, we introduce a robust and efficient technique for rapid design of compact RF circuits. Our approach exploits two-level space mapping (SM) correction of an equivalent circuit model of the structure under design. The first SM layer (local correction) is utilized to ensure good matching between the equivalent circuit and the electromagnetic model at the component level. On the other hand, the global correction allows...
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Evaluation of the Influence of Farming Practices and Land Use on Groundwater Resources in a Coastal Multi-Aquifer System in Puck Region (Northern Poland)
PublicationThis study focuses on the modeling of groundwater flow and nitrate transport in a multi-aquifer hydrosystem in northern Poland, adjacent to Puck Bay (Baltic sea). The main goal was to investigate how changes in land use and farming practices may affect groundwater recharge and submarine groundwater discharge (SGD) to the sea and the associated N-NO3 fluxes. An integrated modelling approach has been developed, which couples the...
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A Substrate Integrated Waveguide (SIW) Bandpass Filter in A Box Configuration With Frequency-Dependent Coupling
PublicationThis letter presents the design of a microwave bandpass filter with frequency-dependent coupling implemented in substrate integrated waveguide (SIW) technology. The proposed filter implements a four-pole generalized Chebyshev filtering function with two transmission zeros. Resonators are arranged in an extended box configuration with dispersive coupling on a main signal path, which produces an extra zero in comparison to classical...
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Determination of impurities in pharmaceutical products using LC-MS
PublicationPharmaceutical products can be contaminated by residues of solvents, reagents (used for the synthesis) or degradation products. Impurities in drug may pose a risk to human health and life, therefore analysis and identification of impurities in pharmaceutical products is veryimportant and inevitable.High performance liquid chromatography coupled with mass spectrometry (MS) is very useful technique for identification impurities in...
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The equations for interactions of polarization modes in optical fibres including the kerr effect
PublicationWe have derived coupled nonlinear Schro¨ dinger equations (CNLSE) for arbitrary polarized light propagation in a single-mode fibre employing electromagnetic field complete description. We used a basis of transverse eigenmodes with appropriate projecting; hence, the nonlinear constants depend on the waveguide geometry. Accounting for a weak nonlinearity, which is connected to the Kerr effect, we have given explicit expressions for...
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MESOSCALE FUNCTIONS OF GPS SLANT DELAY
PublicationThe paper presents a computer module for GPS slant delay determination using data from COAMPS (Coupled Ocean/Atmosphere Mesoscale Prediction System) mesoscale non-hydrostatic model of the atmosphere which is run on IA64 Feniks computer cluster in the Department of Civil Engineering and Geodesy of the Military University of Technology. The slant delay is the result of integrating the ray (eikonal) equation for the spatial function...
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Estimation of a Stochastic Burgers' Equation Using an Ensemble Kalman Filter
PublicationIn this work, we consider a difficult problem of state estimation of nonlinear stochastic partial differential equations (SPDE) based on uncertain measurements. The presented solution uses the method of lines (MoL), which allows us to discretize a stochastic partial differential equation in a spatial dimension and represent it as a system of coupled continuous-time ordinary stochastic differential equations (SDE). For such a system...
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The σ-phase superconductors Nb20.4Rh5.7Ge3.9 and Nb20.4Rh5.7Si3.9
PublicationWe show that the previously unreported ternary σ phases Nb20.4Rh5.7Ge3.9 and Nb20.4Rh5.7Si3.9 are both superconductors with Tc values of approximately 1.9 K. The superconducting transitions were characterized through temperature-dependent magnetic susceptibility, electrical resistance, and specific heat measurements. The Sommerfeld constants, γ, for Nb20.4Rh5.7Ge3.9 and Nb20.4Rh5.7Si3.9 are 89(1) mJ mol-f.u.−1K−2 and 86(1) mJ mol-f.u.−1K−2...
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A Novel Synthesis Technique for Microwave Bandpass Filters with Frequency-Dependent Couplings
PublicationThis paper presents a novel synthesis technique for microwave bandpass filters with frequency-dependent couplings. The proposed method is based on the systematic extraction of a dispersive coupling coefficient using an optimization technique based on the zeros and poles of scattering parameters representing two coupled resonators.The application of this method of synthesis is illustrated using two examples involving four and five-pole...
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Results of modeling of pharmaceuticals mixtures toxicity with deviation ratio and best-fit functions models using Aliivibrio fischeri bacterium as model organism
Open Research DataThe research was concerned with verifying the impact of mixtures of nine pharmaceuticals against a selected organism, i.e., the bacterium Aliivibrio fischeri. A. fisheri is used as a model organism in the monitoring of acute toxicity in environmental and reference samples in Microtox® systems. Tested pharmaceuticals, namely: diclofenac (sodium salt),...
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Gdyńskie chłodnie portowe - studium przypadku przemysłowej architektury portowej okresu modernizmu
PublicationArtykuł podejmuje tematykę obiektów monumentalnej architektury przemysłowej portu gdyńskiego, o funkcji chłodni. Rozwój technologii chłodzenia spowodował, że od połowy XIX w. obiekty takie budowano w dużych, zazwyczaj międzynarodowych ośrodkach dla zapewnienia wysokiego poziomu obsługi handlu produktami łatwo psującymi się. Dynamiczny rozwój portowego zaplecza Gdyni w okresie międzywojennym zaowocował powstaniem aż trzech budowli...
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W stronę spersonalizowanego miasta?
PublicationOd czasów Platona i Witruwiusza nie ustają wysiłki na rzecz dążenia do prawdy, dobra i piękna skupione wokół miasta jako idei politycznej i przestrzeni fundamentalnie egzystencjalnej. Towarzyszy im od wieków myślenie o idealnej organizacji i kompozycji miasta, o poczuciu podmiotowości mieszkańców i użytkowników, doświadczaniu przez nich czasu i przestrzeni. Szczególnie w ostatnich dekadach, gdy już nie przestrzeń, a czas i jego...
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Temperature influences on shear stability of a nanosize plate with piezoelectricity effect
PublicationPurpose The purpose of this paper is to predict the mechanical behavior of a piezoelectric nanoplate under shear stability by taking electric voltage into account in thermal environment. Design/methodology/approach Simplified first-order shear deformation theory has been used as a displacement field. Modified couple stress theory has been applied for considering small-size effects. An analytical solution has been taken into account...
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Computationally Efficient Design Optimization of Compact Microwave and Antenna Structures
PublicationMiniaturization is one of the important concerns of contemporary wireless communication systems, especially regarding their passive microwave components, such as filters, couplers, power dividers, etc., as well as antennas. It is also very challenging, because adequate performance evaluation of such components requires full-wave electromagnetic (EM) simulation, which is computationally expensive. Although high-fidelity EM analysis...
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Hybrid model of geared rotor system
PublicationIn the paper a hybrid model of a geared multirotor system has been developed. The model is obtained by application of both the modal decomposition methodology and the spatial discretization method. Reduced modal model was constructed for the system without gyroscopic and damping effects. The gyroscopic interaction, damping and other phenomena which are difficult to include in the modal approach were modeled by application of simply...
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Detailed studies of superconducting properties of Y2Pd1.25Ge2.75
PublicationWe report a successful synthesis of a high-purity intermetallic germanide Y2Pd1.25Ge2.75, crystallizing in the disordered variant of the AlB2-type structure. A single-phase sample was obtained via arc-melting by deliberately tuning the composition out of the ideal 2:1:3 ratio. Specific heat, electrical resistivity and magnetization measurements show that the compound is a weakly-coupled (λ e-p = 0.58) type-II superconductor with...
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Modified dynamic time warping method applied to handwritten signature authenticity verification
PublicationA signature verification system based on static features and time-domain functions of signals obtained using a tablet has been presented in the paper. The signature verification method, based mainly on dynamic time warping coupled with some signature image features, has been described. The FRR measures reflecting the method’s efficiency have been evaluated for verification attempts performed directly after obtaining model signatures...
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Influence of Installation Effects on Pile Bearing Capacity in Cohesive Soils – Large Deformation Analysis Via Finite Element Method
PublicationIn this paper, the whole process of pile construction and performance during loading is modelled via large deformation finite element methods such as Coupled Eulerian Lagrangian (CEL) and Updated Lagrangian (UL). Numerical study consists of installation process, consolidation phase and following pile static load test (SLT). The Poznań site is chosen as the reference location for the numerical analysis, where series of pile SLTs...
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Parametrical Method for Determining Optimal Ship Carrying Capacity and Performance of Handling Equipment
PublicationThe paper presents a method of evaluating the optimal value of the cargo ships deadweight and the coupled optimal value of cargo handling capacity. The method may be useful at the stage of establishing the main owners requirements concerning the ship design parameters as well as for choosing a proper second hand ship for a given transportation task. The deadweight and the capacity are determined on the basis of a selected economic...
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Superconductivity on a Bi Square Net in LiBi
PublicationWe present the crystallographic analysis, superconducting characterization and theoretical modeling of LiBi, that contains the lightest and the heaviest nonradioactive metal. The compound crystallizes in a tetragonal (CuAu-type) crystal structure with Bi square nets separated by Li planes (parameters a = 3.3636(1)Å and c = 4.2459(2) Å, c/a = 1.26). Superconducting state was studied in detail by magnetic susceptibility and heat...
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A New Approach to Capacitive Sensor Measurements Based on a Microcontroller and a Three-Gate Stable RC Oscillator
PublicationA complete smart capacitive sensor solution basedA complete smart capacitive sensor solution based on a microcontroller was developed. This approach includes the development of both the hardware and software. The hardware part comprises an 8-bit microcontroller equipped with two timers/counters and a three-gate stable RC relaxation oscillator. The software part handles system configuration, measurement control, communication control,...
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Flexomagneticity in buckled shear deformable hard-magnetic soft structures
PublicationThis research work performs the first time exploring and addressing the flexomagnetic property in a shear deformable piezomagnetic structure. The strain gradient reveals flexomagneticity in a magnetization phenomenon of structures regardless of their atomic lattice is symmetrical or asymmetrical. It is assumed that a synchronous converse magnetization couples both piezomagnetic and flexomagnetic features into the material structure....
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A Novel Trust-Region-Based Algorithm with Flexible Jacobian Updates for Expedited Optimization of High-Frequency Structures
PublicationSimulation-driven design closure is mandatory in the design of contemporary high-frequency components. It aims at improving the selected performance figures through adjustment of the structure’s geometry (and/or material) parameters. The computational cost of this process when employing numerical optimization is often prohibitively high, which is a strong motivation for the development of more efficient methods. This is especially...
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Numerically efficient algorithm for compact microwave device optimization with flexible sensitivity updating scheme
PublicationAn efficient trust-region algorithm with flexible sensitivity updating management scheme for electromagnetic (EM)-driven design optimization of compact microwave components is proposed. During the optimization process, updating of selected columns of the circuit response Jacobian is performed using a rank-one Broyden formula (BF) replacing finite differentiation (FD). The FD update is omitted for directions sufficiently well aligned...
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Low energy electron attachment to platinum(II) bromide (PtBr2)
PublicationtDissociative electron attachment to PtBr2in the gas phase was studied in the low electron energy rangefrom zero up to 10 eV with an energy resolution of 150 meV. The experiments were carried out using ahemispherical electron monochromator coupled with a quadrupole mass spectrometer and pulse count-ing acquisition system. The only anion observed was Br−. This ion is formed at three resonance electronenergies: 0.4 eV, 1.2 eV and...
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COMPARISON OF INFINITE ELEMENT MODELS
PublicationThe main objective of this paper is to show the comparison of two models of infinite ab- sorbing layer with increasing damping in numerical investigations of elastic wave prop- agation in unbounded structures. This has been achieved by the Authors by a careful in- vestigation of two different engineering structures characterised by gradually increasing geometrical and mathematical description complexities. The analysis included...
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Principles of smoking
PublicationTreatment of a large variety of foods with wood smoke has been practiced for centuries—predominantlymeats, poultry, and fish, but also scallops, cheeses, prunes, paprika, and themalt used to produce whiskey and some sorts of beer.The process usually includes salting and partial drying; it may also be coupled with heating. The aim is to increase the shelf life of the products, prevent food poisoning, and add a desirable smoky flavor....
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Domestic ORC micro-CHP combined with a commercial gas boiler
PublicationThe chapter presents the results of experimental studies conducted during the launch of the first in Poland demonstration prototype of the micro ORC coupled to a domestic gas boiler. The accomplished studies indicated the possibility for the ORC module to work with such boiler (autonomous source of heat) with a prototype single-stage axial micro turbine as the expansion machine. Confirmation of that fact has been delineated in...