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Comparative Study of Integer and Non-Integer Order Models of Synchronous Generator
PublikacjaThis article presents a comparison between integer and non-integer order modelling of a synchronous generator, in the frequency domain as well as in the time domain. The classical integer order model was compared to one containing half -order systems. The half-order systems are represented in a Park d-q axis equivalent circuit as impedances modelled by half-order transmittances. Using a direct method based on the approximation...
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Acoustic Streaming Induced by Periodic and Aperiodic Sound in a Bubbly Liquid
PublikacjaThe vortex ow which follows intense sound propagating in a bubbly liquid, is considered. The reasons for acoustic streaming are both nonlinearity and dispersion. That makes streaming especial as compared with that in a Newtonian uid. Conclusions concern the vortex ow induced in a half-space by initially harmonic or impulse Gaussian beam. The vortex ow recalls a turbulent ow with increasing in time number of small-scale vortices...
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Impact of Boundary Conditions on Acoustic Excitation of EntropyPerturbations in a Bounded Volume of Newtonian Gas
PublikacjaExcitation of the entropy mode in the field of intense sound, that is, acoustic heating, is theoreticallyconsidered in this work. The dynamic equation for an excess density which specifies the entropy mode,has been obtained by means of the method of projections. It takes the form of the diffusion equation withan acoustic driving force which is quadratically nonlinear in the leading order. The diffusion coefficient isproportional...
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Brain circuit imprints of developmental 17α-Ethinylestradiol exposure in guppies (Poecilia reticulata): Persistent effects on anxiety but not on reproductive behaviour
PublikacjaThe effects of endocrine disruptors may vary with the timing of exposure. The physiological implications of adult exposure are present during and shortly after exposure while embryonic exposure can imprint changes manifested in adulthood. In this study, guppy (Poecilia reticulata) embryos were exposed to 2 and 20 ng/L of 17α-ethinylestradiol during development via the mother and reared in clean water from gestation until 6 months...
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Space and spatial practices in times of confinement. Evidence from three European countries: Austria, France and Poland
PublikacjaIn the first half of 2020, millions of people were subjected to drastic restrictions aimed at limiting the spread of the Covid-19 disease. Austria, France and Poland have implemented a lockdown to varying degrees and for varying lengths of time. This is an unprecedented situation in Europe: until now, even in times of war, curfew measures have never been applied 24 h a day. The research presented in this article was carried out...
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Various cases of preservation and adaptive reuse Heritage Buildings in the Port of Gdynia
PublikacjaThe port of Gdynia contains a diverse range of heritage assets, starting with its spatial layout which is an urban concept designed in the first half of the 1920s. It is important to point out, this historically-shaped harbor space is preserved in its general idea and still functioning in port activities. Another significant element is the structural, technological solution which was the basis for constructing the entire port area...
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Influence of finishing colour on the efficiency of automated production line for wooden doors
PublikacjaPorta KMI Poland S.A. company has implemented a fully automated intelligent technological line TechnoPORTA for customized mass-production of technical door leaves. Each door leaf is provided with a unique QR code. It allows the line modules to individually adjust the machining parameters to the currently processed element according to the IT controlling system. Before en-tering the TechnoPorta line, the door leaves are not sorted,...
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ANALYSIS OF BEARING CLEARANCE AND WIDTH OF OIL GROOVE ON CHARACTERISTIC OF FLUID FILM IN HYDRODYNAMIC MAIN CRANKSHAFT BEARINGS
PublikacjaAbstract Paper represents analysis of influence of oil groove width and bearing clearance on characteristics of oil film in hydrodynamic journal main crankshaft bearing. Analysis was performed in purpose to define influence of bearing clearance and dimensions of oil groove on static characteristics and manufacturability of half shelf bearings in industrial high-volume production. Computer simulations was made using ARTbear program...
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Billiard in a rotating half-plane
PublikacjaThe main objective of this research is to study the properties of a billiard system in an unbounded domain with moving boundary. We consider a system consisting of an infinite rod (a straight line) and a ball (a massless point) on the plane. The rod rotates uniformly around one of its points and experiences elastic collisions with the ball. We define a mathematical model for the dynamics of such a system and write down asymptotic...
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Price convergence in the European Union and in the new member states
PublikacjaThis paper examines price dispersion in the European Union (EU15) and in three New Member States (Poland, Hungary and the Czech Republic) between 1995 and 2006. The analysis utilizes both disaggregate and aggregate price data, including the prices of 157 products and two indices constructed using two different weighting procedures. For each category of goods the price dispersion is lower in EU15 than EU15 plus 3 NMS. Sigma convergence...
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Frequency and phase analysis of daily reprocessed solutions from selected EPN stations relating to geological phenomena,
PublikacjaThe main assumption of this research was to check and verify the behaviour of a few EPN (European Permanent Network) stations on both sides of the Teisseyre-Tornquist zone (T-T zone), which is located on Polish territory and crosses Poland almost in half. The selected EPN stations’ time series were a subject of frequency and phase analysis. The main purpose of the research was to verify if there is any correspondence between stations...
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CONTEMPORARY APPROACH TOWARDS RESPONSIVE ARCHITECTURE
PublikacjaConstantly changing environment pressures every living for a change, and response becomes a basic reaction of any living form. Change is a natural reaction that enables survivor of all the species. However, in architecture, the responsive structure did not take important role until the twentieth century. During that time many concepts and building introduced kinematics into the discipline. In the late 50 and 60 of XX century, visionary...
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Hybrid Technique Combining the FDTD Method and Its Convolution Formulation Based on the Discrete Green's Function
PublikacjaIn this letter, a technique combining the finite-difference time-domain (FDTD) method and its formulation based on the discrete Green's function (DGF) is presented. The hybrid method is applicable to inhomogeneous dielectric structures that are mutually coupled with wire antennas. The method employs the surface equivalence theorem in the discrete domain to separate the problem into a dielectric domain simulated using the FDTD method...
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Small Hydropower Plants in Pomerania: The Example of Evolution of Modern Industrial Brick Architecture
PublikacjaModernism is usually recognized and associated with the aesthetics of the International Style, represented by white-plastered, horizontally articulated architecture with skimpy decoration, where function was the main imperative of the architects’ ambitions. The brick face of Modernism in Northern Europe reflected, in fact, the complexity of the modern change, breaking ties with the historic styles of the 19th century and being...
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Photoresponsive Amide-Based Derivatives of Azobenzene-4,4′-Dicarboxylic Acid—Experimental and Theoretical Studies
PublikacjaAzobenzene derivatives are one of the most important molecular switches for biological and material science applications. Although these systems represent a well-known group of compounds, there remains a need to identify the factors influencing their photochemical properties in order to design azobenzene-based technologies in a rational way. In this contribution, we describe the synthesis and characterization of two novel amides...
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A higher order transversely deformable shell-type spectral finite element for dynamic analysis of isotropic structures
PublikacjaThis paper deals with certain aspects related to the dynamic behaviour of isotropic shell-like structures analysed by the use of a higher order transversely deformable shell-type spectral finite element newly formulated and the approach known as the Time-domain Spectral Finite Element Method (TD-SFEM). Although recently this spectral approach is reported in the literature as a very powerful numerical tool used to solve various...
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Efficient RSS-Based DoA Estimation for ESPAR Antennas Using Multiplane SDR Calibration Approach
PublikacjaIn this paper, we have introduced a new method to improve overall efficiency of direction-of-arrival (DoA) estimation scheme relying on received signal strength (RSS) values measured at the output port of electronically steerable parasitic array radiator (ESPAR) antenna. The proposed approach uses software-defined radio (SDR) setup and power pattern cross-correlation (PPCC) estimator involving multiple calibration planes. By placing...
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Markthal Rotterdam as a contemporary continuation of nineteenth-entury market-halls' architectural ideas in Europe, 3rd International Multidisciplinary Scientific Conference, Social Sciences and Arts, Conference proceedings, book 4, Arts, Performing Arts, Architecture and design, Volume II, Vienna, Austria; pp. 391-398
PublikacjaIn the nineteenth century the reorganization of the European city local trading model resulted in the network of a series of newly constructed covered market halls. The large-format objects superseded the trade forms of previous streets and squares. In the second half of the twentieth century the panoply of the public trade markets was dominated by food super- and hypermarkets. It seemed that the era of old-time market halls,...
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Phototransformation of three selected pharmaceuticals, naproxen, 17α-Ethinylestradiol and tetracycline in water: Identification of photoproducts and transformation pathways
PublikacjaTransformation products (TPs) may be formed during various processes, however, it was proved that one of the main mechanisms responsible for degradation of pharmaceuticals in natural waters is photolysis. Three compounds were selected, tetracycline (TC), 17-α-ethinylestradiol (EE2) and naproxen (NAP), for degradation experiments which were performed using a xenon lamp emitting light with a spectrum closely approximating that of...
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ARCHITECTURE OF HYDROPOWER PLANTS IN POMORZE
PublikacjaThe history of energetic use of the rivers of Pomerania (Pomorze) is traced from the late Middle Ages. Their potential due to geographical specificity of the region was still attractive in the era of electricity of the19th and the first half of the 20th century. Configuration of the terrain, geological, and natural restrictions, but mainly energetic potential of particular localization were crucial for economical success of the...
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Prediction of Overall In Vitro Microsomal Stability of Drug Candidates Based on Molecular Modeling and Support Vector Machines. Case Study of Novel Arylpiperazines Derivatives
PublikacjaOther than efficacy of interaction with the molecular target, metabolic stability is the primary factor responsible for the failure or success of a compound in the drug development pipeline. The ideal drug candidate should be stable enough to reach its therapeutic site of action. Despite many recent excellent achievements in the field of computational methods supporting drug metabolism studies, a well-recognized procedure to model...
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Mercury concentrations in marine biota with special focus on grey and ringed seals
PublikacjaMarine organisms are exposed and sensitive to effects of environmental contamination by heavy metals including different forms of mercury. Baltic seals as the top predators of the marine ecosystem are even more endangered due to (considerable) longevity as well as a long biological half-time of toxin elimination. The concentrations of mercury in seals from the Baltic is poorly known, thus the aim of this work is to determine and...
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COMPARATIVE ANALYSIS OF RESULTS OF APPLICATION OF MARKOV AND SEMI-MARKOV PROCESSES TO RELIABILITY MODELS OF MULTI-STATE TECHNICAL OBJECTS
PublikacjaDuring rational operation of technical objects and systems various operational decisions are made and decision-making process itself should be consisted in selecting that considered most favourable out of all possible to be taken. Choice of such decision is possible after taking into account many different information items but it never be completely correct without accounting for data and indices dealing with reliability. In...
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Numerical analysis of elastic wave propagation in unbounded structures
PublikacjaThe main objective of this paper is to show the effectiveness and usefulness of the concept of an absorbing layer with increasing damping (ALID) in numerical investigations of elastic wave propagation in unbounded engineering structures. This has been achieved by the authors by a careful investigation of three different types of structures characterised by gradually increasing geometrical and mathematical description complexities....
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Sundials of St Mary’s Church in Gdańsk / Zegary słoneczne kościoła pw. Wniebowzięcia Najświętszej Panny Marii w Gdańsku
PublikacjaThe paper presents contemporary research evidence of form, function and history of the sundials of St Mary’s Church in Gdańsk. The discussed sundials are located on the southern wall of the church transept. The sundial, which is believed to be made by Lorenzo Zachau in 1533, is placed on the west side of the western window, at the edge of the wall. The face of this sundial is separated by a horizontal line into two parts. The upper...
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Face with Mask Detection in Thermal Images Using Deep Neural Networks
PublikacjaAs the interest in facial detection grows, especially during a pandemic, solutions are sought that will be effective and bring more benefits. This is the case with the use of thermal imaging, which is resistant to environmental factors and makes it possible, for example, to determine the temperature based on the detected face, which brings new perspectives and opportunities to use such an approach for health control purposes. The...
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MODELOWANIE TURBINY WIATROWEJ Z DWOMA PRZECIWBIEŻNIE OBRACAJĄCYMI SIĘ WIRNIKAMI
PublikacjaW artykule przedstawiono sposoby modelowania dwuwirnikowej turbiny wiatrowej z wykorzystaniem technik Obliczeniowej Mechaniki Płynów. Omówiono uproszczone metody modelowania Actuator Disc i Actuator Line Method oraz aspekty związane z dokładnym odwzorowaniem turbiny na siatce obliczeniowej. Zaprezentowano przykładowe wyniki obliczeń turbiny dwuwirnikowej złożonej z wirników NREL o mocy nominalnej 5 MW każdy. Do wykonania badań...
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Carotid Artery Stenting and Blood–Brain Barrier Permeability in Subjects with Chronic Carotid Artery Stenosis
PublikacjaFailure of the blood-brain barrier (BBB) is a critical event in the development and progression of diseases such as acute ischemic stroke, chronic ischemia or small vessels disease that affect the central nervous system. It is not known whether BBB breakdown in subjects with chronic carotid artery stenosis can be restrained with postoperative recovery of cerebral perfusion. The aim of the study was to assess the short-term effect...
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Two highly thermostable paralogous single-stranded DNA-binding proteins from Thermoanaerobacter tengcongensis
PublikacjaThe thermophilic bacterium Thermoanaerobacter tengcongensis has two single-stranded DNA-binding (SSB) proteins, designated TteSSB2 and TteSSB3. In a SSB complementation assay in Escherichia coli, only TteSSB3 took over the in vivo function of EcoSSB. We have cloned the ssb genes obtained by PCR and have developed E. coli overexpression systems. The TteSSB2 and TteSSB3 consist of 153 and 150 amino acids with a calculated molecular...
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Application of commercial microwave links (CMLs) attenuation for quantitative estimation of precipitation
PublikacjaPrecipitation estimation models are typically sourced by rain gauges, weather radars and satellite observations. A relatively new technique of precipitation estimation relies on the network of Commercial Microwave Links (CMLs) employed for cellular communication networks: the rain-inducted attenuation in the links enables the precipitation estimation. In the paper, it is analysed to what extent the precipitation derived from CML...
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Profesor Stanisław Trzetrzewiński – polski prekursor niepewności pomiaru
PublikacjaArtykuł ma na celu przybliżenie sylwetki Profesora Stanisława Trzetrzewińskiego, jako pierwszego kierownika Katedry Miernictwa Elektrycznego na Wydziale Elektrycznym Politechniki Gdańskiej, odpowiedzialnego za organizację Katedry po wojnie, dydaktyka, ale przede wszystkim wybitnego metrologa. Profesora Stanisława Trzetrzewińskiego można nazwać polskim prekursorem teorii niepewności pomiaru, co potwierdza wygłoszony w 1952 roku...
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Influence of laser processing of the low alloy medium carbon structural steel on the development of the fatigue crack
PublikacjaThe paper contains the results of the structural analysis, hardness tests and fatigue tests conducted for the medium carbon structural steel with low content of Cr and Ni after its processing with CO2 laser beam. Pre-cracks were made in the round compact tension (RCT) specimen used for fatigue test. Next, four paths, parallel to each other, were melted on both sides of the samples using a laser beam. The paths were perpendicular...
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Satellite Laser Ranging technique as a tool for the determination of the Schwarzschild, de Sitter and Lense-Thirring effects
PublikacjaSatellite Laser Ranging (SLR) is a modern technique used in various research areas and applications related to geodesy and geodynamics. It is commonly used for tasks such as establishing the International Terrestrial Reference Frame (ITRF), monitoring Earth Orientation Parameters (EOP), determining the geocenter, measuring fundamental physical constants, calibrating microwave tracking techniques, conducting time transfer experiments,...
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Pupil detection supported by Haar feature based cascade classifier for two-photon vision examinations
PublikacjaThe aim of this paper is to present a novel method, called Adaptive Edge Detection (AED), of extraction of precise pupil edge coordinates from eye image characterized by reflections of external illuminators and laser beams. The method is used for monitoring of pupil size and position during psychophysical tests of two-photon vision performed by dedicated optical set-up. Two-photon vision is a new phenomenon of perception of short-pulsed...
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Medieval Bourgeois Tenement Houses as an Archetype for Contemporary Architectural and Construction Solutions: The Example of Historic Downtown Gdańsk
PublikacjaThe basic urban tissue of medieval European cities consisted of brick townhouses. In the cities of northern Europe, these tenements were characterised by a block based on an elongated rectangular plan, covered with a gable roof with a ridge oriented perpendicularly to the street. The side walls of the tenement house were common for both neighbours and constituted a basic structural element. The gable façades were not loaded with...
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Identification of Shear Modulus Parameters of Half-space Inhomogeneous by Depth
PublikacjaThe paper propose a method for determining of the parameters of the exponential shear modulus of a functionally graded half-space based on the solution of the problem of a pure shear of an elastic functionally graded half-space by a strip punch. The solution of the integral equation of the contact problem is constructed by asymptotic methods with respect to the dimensionless parameter. The dependence of contact stresses on the...
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Modernisation of existing hospitals
PublikacjaProgress in medicine and development of medical technologies directly affect the evolution of methods for treating patients in hospitals. The main task of 19th-century hospitals was patient care and nursing, while the aim of hospitals today is to diagnose and treat patients effectively in the shortest time possible. The changes which are taking place in methods of treatment affect the functional-spatial layout of hospitals. This...
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IN VITRO PROPAGATION OF RHODODENDRON TOMENTOSUM - AN ENDANGERED ESSENTIAL OIL BEARING PLANT FROM PEATLAND
PublikacjaRhododendron tomentosum Harmaja (formerly Ledum palustre L.) is a medicinal peat bog plant native to northern Europe, Asia and North America. This plant has a distinctive aroma thanks to the presence of essential oil, to which it also owes its anti-inflammatory, analgesic, antimicrobial and insecticidal properties. However, in Europe R. tomentosum is classified as an endangered species, mainly due to degradation of peatlands. In...
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Characterization of the Functionally Graded Shear Modulus of a Half-Space
PublikacjaIn this article, a method is proposed for determining parameters of the exponentialy varying shear modulus of a functionally graded half-space. The method is based on the analytical solution of the problem of pure shear of an elastic functionally graded half-space by a strip punch. The half-space has the depth-wise exponential variation of its shear modulus, whose parameters are to be determined. The problem is reduced to an integral...
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Czynniki kształtujące środowisko pacjenta w szpitalu
PublikacjaSzpital jest miejscem szczególnym – z założenia przebywają w nim osoby, znajdujące się w sytuacji niekomfortowej. Możliwości adaptacji w nowym środowisku u osób chorych, osłabionych lub osób z niepełnosprawnościami są znacząco obniżone, a przecież szpital należy do budynków o najbardziej skomplikowanej strukturze funkcjonalno-przestrzennej. Stan emocjonalny pacjenta w środowisku szpitalnym jest uzależniony od relacji z lekarzami...
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Anti-plane shear waves in an elastic strip rigidly attached to an elastic half-space
PublikacjaWe consider the anti-plane shear waves in a domain consisting of an infinite layer with a thin coating lying on an elastic half-space. The elastic properties of the coating, layer, and half-space are assumed to be different. On the free upper surface we assume the compatibility condition within the Gurtin–Murdoch surface elasticity, whereas at the plane interface we consider perfect contact. For this problem there exist two possible...
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The role of isolated farmsteads in the open landscape protection on the example of Kashubia
PublikacjaAs a result of the social and economic transformation of rural areas, open landscapes are disappearing. Former farmsteads are being devastated or beginning to lose their landscape context due to the spread of residential building development. At the same time, in many places, the farmstead form is clearly legible and remains an element with which the view is structured and enriched. The article was aimed at drawing attention to...
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Design and evaluation of a base module of active power electronic transformer
PublikacjaThis paper presents an active power electronic transformer (APET) based on modular structure. The proposed three phase APET consists of at least three base modules (BM). The input/output stage of the BM is based on half-bridge sub modules. The isolation stage includes a medium frequency transformer and is realized as a dual half-bridge. The paper describes construction process and explains the control strategy. The theoretical...
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SiC-based phase-shift dual half bridge DC-DC converter as a key component of multilevel cascaded MV converters
PublikacjaThe paper describes SiC-based dual half bridge (DHB) DC-DC converter considered as a key component of high frequency isolated multilevel cascaded medium voltage converters. Two topologies of bi-directional DC-DC converters: the resonant half-bridge DC-DC converter and the phase-shift DHB converter are compared in the paper. Experimental results of SiC-based 50 kHz DHB DC-DC converter are presented in the paper.
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Single-phase power electronics transformer with active functions for smart grid
PublikacjaThis paper presents the control of one cell of a modular single-phase power electronics transformer with active functions for meeting the smart grid concept. In this way, the converter could be used not only as a conventional transformer but also for grid such as reactive power, harmonic elimination and energy storage. The topology of the cell is composed by a bidirectional converter with three stages: a half bridge in the input...
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A MEASUREMENT SYSTEM FOR MONITORING CARDIOVASCULAR EVENTS IN SYNCOPE PATIENTS
PublikacjaSyncope phenomena is an abrupt and transient loss of consciousness leading to interruption of awareness of one’s surroundings and falls with risk of injury. Syncope is often followed by complete and usually rapid spontaneous recovery. It is said that half of all individuals experience syncopal event at least once during their life. The condition can occur at any age and happens in people with and without other medical problems....
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Exploring the Beam Squint Effects on Reflectarray Perfromance: A Comprehensive Analysis of the Specular and Scattered Reflection of the Unit Cell
PublikacjaIn this article, the phenomena of beam deviation in reflectarray is discussed. The radiation pattern of the unit cell, which plays a vital role in shaping the beam of the reflectarray, is analyzed by considering undesired specular and scattered reflections. These unwanted reflections adversely affect the pattern of the single unit cell, thereby reducing the overall performance of the reflectarray. To conduct our investigations,...
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Evaluating the challenges and needs of parents caring for children with Williams syndrome: A preliminary study from Poland
PublikacjaBackground: Although physical, cognitive and behavioural manifestations of Williams syndrome(WS) affect every dimension of caregivers lives, no studies on the parental experiences of caringfor a WS child have to date been carried out in Poland.Methods: In order to identify the challenges and needs of Polish carers of WS children a survey wasconducted...
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Electro-thermal buckling of elastically supported double-layered piezoelectric nanoplates affected by an external electric voltage
PublikacjaPurpose Thermal buckling of double-layered piezoelectric nanoplates has been analyzed by applying an external electric voltage on the nanoplates. The paper aims to discuss this issue. Design/methodology/approach Double-layered nanoplates are connected to each other by considering linear van der Waals forces. Nanoplates are placed on a polymer matrix. A comprehensive thermal stress function is used for investigating thermal buckling....
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Anti-plane surface waves in media with surface structure: Discrete vs. continuum model
PublikacjaWe present a comparison of the dispersion relations derived for anti-plane surface waves using the two distinct approaches of the surface elasticity vis-a-vis the lattice dynamics. We consider an elastic half-space with surface stresses described within the Gurtin–Murdoch model, and present a formulation of its discrete counterpart that is a square lattice half-plane with surface row of particles having mass and elastic bonds different...