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Search results for: manuvering characteristic
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Geometrically nonlinear FEM analysis of 6-parameter resultant shell theory based on 2-D Cosserat constitutive model
PublicationWe develop the elastic constitutive law for the resultant statically and kinematically exact, nonlinear, 6-parameter shell theory. The Cosserat plane stress equations are integrated through-the- thickness under assumption of the Reissner-Mindlin kinematics. The resulting constitutive equations for stress resultant and couple resultants are expressed in terms of two micropolar constants: the micropolar modulus Gc and the micropolar...
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The shape of an ROC curve in the evaluation of credit scoring models
PublicationThe AUC, i.e. the area under the receiver operating characteristic (ROC) curve, or its scaled version, the Gini coefficient, are the standard measures of the discriminatory power of credit scoring. Using binormal ROC curve models, we show how the shape of the curves affects the economic benefits of using scoring models with the same AUC. Based on the results, we propose that the shape parameter of the fitted ROC curve is reported...
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Parametric method applicable in calculating breakout force and time for lifting axisymmetric objects from seabed.
PublicationThe issue of calculating parameters for lifting objects of axisymmetric shapes from the seabed is studied. The article presents the results of numerical simulation examination of the equation formulated by Foda for the force needed to extricate the object from the seabed depending on soil and water parameters, extrication speed, and object diameter. The simulations were performed within the range of parameters characteristic for...
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Inverse heat transfer problem solution of sounding rocket using moving window optimization
PublicationAn Inverse Heat Transfer Problem is solved for a sounding rocket module given its geometry and measured temperature profile. The solution is obtained via moving window optimization, a technique for solving inverse dynamics. An analysis is performed to modify the method to avoid oscillatory behavior of the resulting heat flux profile. The method parameters are tuned in relation to characteristic phases of the flight. Results are...
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New model of cooperation between logistics center and maritime container terminal
PublicationThe following article presents the innovative concept of logistics centers called “port-centric logistics”, which finds close co-operation with maritime container port. This concept can reduce the costs of logistics operations. In the first part the author focuses on describing the specifics of logistics centers. The following parts include characteristic of “port-centric logistics” concept. The last part of the paper contains...
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Non-Wave Variations in Temperature Caused by Sound in a Chemically Reacting Gas
PublicationA weakly nonlinear generation of non-acoustic modes in the field of sound in a gas is considered. An exotericchemical reaction of A->B type, which takes place in a gas, may be reversible or not. Two types of sound areconsidered, low-frequency and high-frequency as compared with the characteristic time of a chemical reaction.For both these cases, the governing equations of non-acoustic modes are derived and conclusions of the efficiencyof...
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STRATEGIA DOBORU PROCESU PRODUKCYJNEGO WG. REAKCJI NA ZAMÓWIENIA KLIENTA
PublicationW opracowaniu poruszono zagadnienie doboru strategii wytwarzania w zakresie procesu produkcyjnego. W ramach tego zagadnienia dokonano podziału procesów produkcyjnych wg różnych kryteriów. Skupiano się na podziale procesów wg. reakcji na zamówienia klienta. Przedstawiono pokrótce najistotniejsze cechy charakteryzujące tego typu procesy. By móc określić strategię w zakresie procesu produkcyjnego zestawiono kryteria wyboru procesu...
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Zastosowanie analiz i prognoz ruchu w programowaniu, planowaniu i projektowaniu inwestycji transportowych
PublicationW artykule zostanie przedstawiona charakterystyka procesu planowania i realizacji inwestycji transportowych ze szczególnym uwzględnieniem roli analiz i prognoz ruchu. Przedstawione fazy planowania, projektowania i realizacji inwestycji transportowych omówiono na przykładach wielu inwestycji prowadzonych w ostatnich latach na obszarze miasta Gdańska i województwa pomorskiego. Szczególną uwagę poświęcono roli analiz i prognoz ruchu...
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Projekt stanowiska badawczego do wyznaczania charakterystyki ogólnej silnika spalinowego ZS przy wykorzystaniu hydraulicznego układu odbioru mocy
PublicationPrzedstawiono projekt stanowiska badawczego służącego do wyznaczania charakterystyki ogólnej silnika pojazdu ciężarowego, wykorzystując przystawkę odbioru mocy do napędu układu hydraulicznego generującego obciążenie silnika w różnych punktach jego pracy. Przedstawiono założenia projektowe oraz ograniczenia konstrukcyjne. Omówiono zasadę działania stanowiska i metodę wyznaczania charakterystyki. Opisano układ hydrauliczny oraz układ...
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O-substituted tetrahydroxamate derivatives of p-tert-butylcalix[4]arene as receptors for transition and heavy metal cations
PublicationTetrasubstituted O-hydroxamate derivatives of p-tert-butylcalix[4]arene were applied as active materials in ion-selective membrane electrodes and were tested towards Pb-selectivity. The electrodes gave near-Nernstian characteristics for Pb2+ cations. The selectivity coefficients were determined. The influence of plasticizer on the electrode behaviour was studied. The dependence of the chemical structure on selectivity coefficients...
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Testing Stability of Digital Filters Using Multimodal Particle Swarm Optimization with Phase Analysis
PublicationIn this paper, a novel meta-heuristic method for evaluation of digital filter stability is presented. The proposed method is very general because it allows one to evaluate stability of systems whose characteristic equations are not based on polynomials. The method combines an efficient evolutionary algorithm represented by the particle swarm optimization and the phase analysis of a complex function in the characteristic equation....
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ANALYSIS OF THE IMPACT OF THE PLANNED SEWAGE DISCHARGE FROM THE ‘NORTH’ POWER PLANT ON THE VISTULA WATER QUALITY
PublicationThe paper presents results of analysis of the industrial sewage discharge impact from the ‘North’ Power Plant on the Vistula water quality around 45+330 of the river kilometer. For the analysis, the two-dimensional models of flow, impurities and temperature transport were used. Hydrological conditions of the analyzed section of the river, characteristic flows and bathymetry of the riverbed in the first instance were defined....
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Nowa metoda optymalizacji pracy ogniw paliwowych.
PublicationPrzedstawiono dynamiczną technikę impedancją jako doskonałe narzędzie służące do określenia optymalnych warunków pracy ogniw paliwowych. Możliwości tej techniki zostały przedstawione na przykładzie ustalenia optymalnej temperatury pracy. Otrzymane wyniki zostały skonfrontowane z charakterystykami prądowo napięciowymi ogniwa.
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Life tests of a rotary single-stage magnetic-fluid seal for shipbuilding applications
PublicationUse of the magnetic fluid seal technology in water is much more difficult technological problem in comparisonto gas or vacuum environment. Some seals constructed up to time been are designed as hybrid, two stagesealing structures with shields or mechanical seals used as protection measures to the magnetic fluid seal.Anyway, there is always problem with immediate contact between magnetic fluid and the environmentalliquid. In the...
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On ship roll resonance frequency
PublicationThe paper deals with the problem of modeling of rolling motion under a variety of excitation parameters. Special emphasis is put on the analysis and prediction of the frequency of the resonant mode of rolling, since it is often an essential issue in terms of motion of a ship related to her safety against capsizing or excessive amplitudes of roll. The research is performed for both free rolling and excited rolling and it is based...
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Low-frequency noise in Au-decorated graphene–Si Schottky barrier diode at selected ambient gases
PublicationWe report results of the current–voltage characteristics and low-frequency noise in Au nanoparticle (AuNP)-decorated graphene–Si Schottky barrier diodes. Measurements were conducted in ambient air with addition of either of two organic vapors, tetrahydrofuran [(CH2)4O; THF] and chloroform (CHCl3), as also during yellow light illumination (592nm), close to the measured particle plasmon polariton frequency of the Au nanoparticle...
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A Wideband Rotary-Joint-Free H-Plane Horn Antenna With 360° Steerable Radiation Pattern Using Gap Waveguide Technology
PublicationConsidering the limitations of electronically steerable antennas such as limited steering span, gain degradation for large steering angles, complexity, and cost, this article is focused on the design of a simple mechanically steerable H-plane horn antenna. It is shown that since there is no need for an electrical connection between the top and bottom sections of a gap waveguide (GWG), if a sectoral horn is properly designed and realized...
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LCF behavior of 2024AA under uni- and biaxial loading taking into account creep pre-deformation
PublicationThis study presents the results of experimental low-cycle fatigue (LCF) tests of aluminum 2024 alloy T3511 temper in uni- and biaxial loading states. Tests were carried out on both the as-received material (hardened extruded rods) and material with different pre-deformation histories. These deformations were carried out in the creep process at 200 °C and 300 °C for two different levels of at each temperature. The pre-deformed material’s...
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Multi-stage magnetic-fluid seals for operating in water - life test procedure, test stand and research results
PublicationThe edge criteria for magnetic-fluid seals durability research are critical for the seal'stechnological usefulness. The magnetic fluid seal technology in water is much moredifficult technological problem in comparison to gas or vacuum environment. There isalways problem with immediate contact between magnetic fluid and the environmentaluninspected liquids. In the paper are presented ways of experiments definitions carried outwith...
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Applicability of arrays of microjets heat transfer correlations to design compact heat exchangers
PublicationThe article presents experimental studies on a compact heat exchanger with heat transfer intensification by means of impinging microjets. The pursuit to provide high performance of heat exchangers is a response to the demand both in economics and in the universal tendency to miniaturization of industrial equipment. This paper presents the design and tests of a prototype, microjet heat exchanger. The modular design of the heat exchanger...
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On Reduced-Cost Design-Oriented Constrained Surrogate Modeling of Antenna Structures
PublicationDesign of contemporary antenna structures heavily relies on full-wave electromagnetic (EM) simulation models. Such models are essential to ensure reliability of evaluating antenna characteristics, yet, they are computationally expensive and therefore unsuitable for handling tasks that require multiple analyses, e.g., parametric optimization. The cost issue can be alleviated by using fast surrogate models. Conventional data-driven...
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Attitudes to tree removal on private properties in two Polish cities.
Open Research DataLarge cities are increasingly faced with declining urban tree cover and related problems, such as increased urban heat islands and flash floods. Reducing these phenomena increasingly has to rely on trees located on private property. However, to effectively engage private landowners on these issues, more attention must be paid to understanding their...
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The electrochemical studies of thin boron-doped diamond films deposited at conductive poly(lactic acid) 3D prints
Open Research DataThe dataset contains the electrochemical characteristics of the electrodes composed of thin boron-doped diamond films coated on commercially available graphene-doped polylactide acid. The boron doping level expressed as the [B]/[C] ratio in the gas phase for these studies was 500 and 10,000 ppm.
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Measurement of mass flow of viscous liquid through a Cylindrical Orifice under laminar flow (CylOr)
Open Research DataThe data was obtained as part of the project "Measurement of mass flow of viscous liquid through a Cylindrical Orifice under laminar flow (CylOr)", in which flow tests of hydraulic oil through a cylindrical orifice with a thickness of l = 25 mm and a throat b = 0.5 (diameter pipes D = 50 mm, orifice diameter d = 25 mm) on the test stand at the Department...
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Koncepcja, realizacja i analiza nowego typu silnika piezoelektrycznego o strukturze wielokomórkowej
PublicationDotychczasowe wyniki badań w obszarze aktuatorów piezoelektrycznych, wskazują ich potencjalnie duże możliwości w przyszłych zastosowaniach specjalnych. W artykule przedstawiono proces projektowania nowego typu silnika piezoelektrycznego. Opisane zostały wybrane topologie maszyn piezoelektrycznych. Przedstawiono wady i zalety silnika ultrasonicznego z falą biegnącą oraz silnika o ruchu obrotowym. W ramach realizacji projektu...
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VEHICLE DYNAMICS (2024)
e-Learning Courses(W) Vehicle dynamics (W-Lecture) - DAPE - WIMiO The course entitled "Vehicle dynamcs" (VD) is conducted for the DAPE WIMiO Students. The VD course is to discuss the following problems: - major problems of vehicle dynamics from the application point of view, - definition of working environment, - types of vehicles, - parameters and characteristics of vehicles, - assessment of performance of vehicles towards design, -...
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Novel doubly perforated broadband microstrip branch-line couplers
PublicationTwo broadband compact doubly perforated hybrid couplers have been designed, manufactured, and measured. To improve frequency characteristics and to reduce circuit dimensions, two kinds of perforations have been introduced: the defected ground structures in the ground plane metallization and photonic bandgap cells in the strip metallization. Measurement results show essential miniaturization (~39% and ~36%) and enhancement of the...
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Alternative Energy: Photovoltaic Solar Cells
PublicationSolar radiation is a fuel for photovoltaic cells and modules, which are a source of electric energy. Viable solar technologies that have been developed in the past are starting to be adopted on a broader and more meaningful global scale across different sectors with ever-increasing market penetration. In this entry, a brief overview of the material properties relevant to solar cell operation, the structure of the solar cell, and electrical...
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A New Method of Noncausal Identification of Time-varying Systems
PublicationThe paper shows that the problem of noncausal identification of a time-varying FIR (finite impulse response) sys- tem can be reformulated, and solved, as a problem of smoothing of the preestimated parameter trajectories. Characteristics of the smoothing filter should be chosen so as to provide the best trade- off between the bias and variance of the resulting estimates. It is shown that optimization of the smoothing operation can...
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NADBUDOWY I RENOWACJE ELEWACJI Z WYKORZYSTANIEM MATERIAŁÓW I ELEMENTÓW LEKKIEJ OBUDOWY
PublicationW artykule omówiono podział i charakterystykę lekkich przegród budowlanych. Przedstawiono możliwości zmian elewacji i wykonywania nadbudowy. Opisano kolejne kroki przygotowania inwestycji dotyczącej projektowania i realizacji nadbudowy obiektu budowlanego.
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Rainscreen panels deformations mods
PublicationIn rainscreen panels designing simplified calculation models are used. For plate computation simply supported panels or panels with fixed edges are commonly used. Such approximations are subjected to large errors that lead to inefficient rainscreen panels design. In order to develop a method for determining the optimal geometry of the rainscreen panels, that would take into consideration the real stiffness of both continuous and...
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Improving Savonius rotor performance by shaping its blade edges
PublicationThe article presents the results of the numerical analysis of the flow inside the Savonius rotor. Particular at-tention has been paid to the vicinity of the blade gap in order to recognise the mechanisms controlling the flow in this area. The conclusions resulting from the analysis made the basis for an attempt to improve Savonius turbine performance via shaping rotor blade edges. The paper presents selected characteristic flow...
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Meiothermus ruber cells as β-galactosidase activity biocatalyst
PublicationThe current study allowed to establish the possibility of using whole cells of thermophilic bacteria Meiothermus ruber as a biocatalyst with β-galactosidase activity. β-galactosidases are used for hydrolysis of lactose as well as for oligosaccharides synthesis. The advantages of using whole bacterial cells catalysis is not only elimination of tedious, expensive protein isolation and/or purification but also stabilization of enzymes...
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Mesoscopic impedance analysis of solid materials surface
PublicationSeveral techniques have been developed in order to characterize electrical properties of surfaces in micrometer/nanometer scale. Obtaining of the spatial distribution of sample resistance, capacitance or potential requires separate measurements performed in different scanning modes. On the other hand, analysis of the frequency response of investigated system enables determination of several physical quantities in single measurement...
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ANALYSIS OF THE PROJECT OF INNOVATIVE FLOATING TURBINE
PublicationThe design of a floating, innovative device for river water aeration and conversion of mechanical energy to electrical energy required the analysis of a number of geometrical and dynamic features. Such an analysis may be carried out on the basis of existing methods of numerical fluid mechanics. Models of pressures, forces and torques characteristic for the conversion of watercourse energy were developed for two basic concepts of...
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Anti-plane waves in an elastic thin strip with surface energy
PublicationWe consider anti-plane motions of an elastic plate taking into account surface energy within the linear Gurtin–Murdoch surface elasticity. Two boundary-value problems are considered that describe complete shear dynamics of a plate with free faces or with free and clamped faces, respectively. These problems correspond to anti-plane dynamics of an elastic film perfectly or non-perfectly attached to a rigid substrate. Detailed analysis...
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Dynamic Signature Vertical Partitioning Using Selected Population-Based Algorithms
PublicationThe dynamic signature is a biometric attribute used for identity verification. It contains information on dynamics of the signing process. There are many approaches to the dynamic signature verification, including the one based on signature partitioning. Partitions are the regions created on the basis of signals describing the dynamics of the signature. They contain information on the shape of the signature characteristic of a...
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Why is the cubic structure preferred in newly formed ice?
PublicationMolecular dynamics was employed to explain the preference for the cubic structure in newly formed crystals of ice. The results showed that in supercooled liquid water the molecules connected by hydrogen bonds are more likely to adopt relative orientations similar to the ones characteristic for cubic ice. The observed preference for certain relative orientations of molecules in the hydrogen-bonded pairs results in the higher probability...
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Tuning transfer function of fiber-optic Fabry-Pérot interferometer via introduction of birefringence in the cavity
PublicationThe study investigates the impact of birefringence exhibited by the cavity material of a fiber-optic Fabry-Pérot interferometer on its transfer function. The theoretical approach to analyze the effect of birefringence in the cavity of a plane Fabry-Pérot interferometer is described. The case of high- and low-finesse interferometer is investigated. It is shown that introduction of a birefringent medium of optimized parameters can...
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ASSESSMENT of PERFORMANCE of UMV (2024)
e-Learning Courses(W) Assessment of Performance of Unmanned Maritime Vehicles (W-Lecture) - DAPE - WIMiO AP-of-UMV (W) -DAPE - WIMiO The course entitled "Assessment of Performance of Unmanned Maritime Vehicles (W-Lecture)" is conducted for the DAPE WIMiO Students. The AP-of-UMV (W) course is to discuss the following problems: - major areas of application of UMV unmanned maritime vehicles, - sea environment, - types of UMV vehicles, -...
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Knowledge Flows in Cluster Organizations
PublicationThis paper aims to identify knowledge flows in cluster organizations (COs). On the basis of a literature analysis on knowledge flows and cluster organizations, the following research question was formulated: What kind of knowledge flows can be identified in cluster organizations and what is their main characteristics? The paper is based on a literature analysis and Grounded Theory methodology, examining four purposefully selected...
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Re-use of historic wooden verandas in Sopot, Poland
PublicationSopot is the best-known seaside resort in Poland. The city is unique with regard not only to its location and natural values, but also its interesting architecture, which dates back to the end of the 19th and the beginning of the 20th century. Wooden verandas are one of the characteristic features of Sopot architecture. Their origin is associated with the Swiss style, which was fashionable at the turn of the 20th century and quite...
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The smartest location for an eco-district– investigation of urban spatial energy efficiency
Publicationncreasing awareness concerning environmental aspects of spatial and architectural planning led to more deliberated projects of eco-districts. Located all over the world and constantly being improved, apart from excellent energetical parameters, most of them have one specific characteristic in common, which is location in the outskirts. The aim of this article was to understand the importance of ecological district location depending...
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Statistical Tuning of Walfisch-Ikegami Model for the Untypical Environment
PublicationThe Walfisch-Ikegami model has been investigated in terms of mobile radio systems designing in the untypical environment such as the maritime container terminal. The measurement equipment and procedures have been described as well as characteristics of investigated environment. Results of the statistical tuning in terms of path loss estimation in such environment have been analysed. The analysis has proved improvement of the path...
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Statistical Tuning of Walfisch-Ikegami Model for the Untypical Environment
PublicationThe Walfisch-Ikegami model has been investigated in terms of mobile radio systems designing in the untypical environment such as the maritime container terminal. The measurement equipment and procedures have been described as well as characteristics of investigated environment. Results of the statistical tuning in terms of path loss estimation in such environment have been analysed. The analysis has proved improvement of the path...
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Selected Issues of Hybrid Outboard Motors
PublicationThe aim of the research reported in the article was designing a hybrid drive system based on an outboard internal combustion engine offered by a selected producer and testing its operating characteristics. The article presents different designs of this type of drive which can be found in the literature and are available in the market. The designed hybrid outboard drive system was tested both on the laboratory test rig and in real...
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3-phase medium frequency transformer for a 100kW 1.2kV 20kHz Dual Active Bridge converter
PublicationThe article presents a three-phase Medium Frequency Transformer being a part of a 100kW 1.2kV 20kHz Dual Active Bridge DC-DC converter. The transformer design is detailed focusing on winding and core power loss calculation. The high power three-phase MFT prototype is presented. The experimental results include the transformer impedance characteristics, no load test and three-phase DAB full load test waveforms
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Novel structure and size-reduction-oriented design of microstrip compact rat-race coupler
PublicationIn this paper, a novel structure of a miniaturized microstrip rat-race coupler has been proposed. Surrogate-based optimization procedures are applied to explicitly reduce the coupler size while maintaining equal power split at the operating frequency of 1 GHz and sufficient bandwidth for return loss and isolation characteristics. The optimization is performed using the objective function with four penalty components. The footprint...
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Tinnitus Therapy Based on High-Frequency Linearization
PublicationThe aim of this work was to present problems related to tinnitus symptoms, its pathogenesis, hypotheses on tinnitus causes, and therapy treatments to reduce or mask the phantom noise. In addition, the hypothesis on the existence of parasitic quantization that accompanies hearing loss was recalled. The paper contains a description of experiments carried out with the application of high-frequency dither having specially formed spectral...
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Biometryczna kontrola dostępu
PublicationOpisano szczegółowo algorytm detekcji oraz identyfikacji człowieka na podstawie punktów nodalnych twarzy. Zdefiniowano pojęcia: biometria, proces pomiaru biometrycznego, metody biometrycznej identyfikacji oraz kontrola dostępu. Przedstawiono opis opracowanego systemu biometrycznej identyfikacji wykorzystującego sztuczne sieci neuronowe. Podano wyniki badań oraz przeprowadzono ich wnikliwą dyskusję.Biometrics is the study of automated...