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Metoda diagnostyki łożysk na podstawie analizy przebiegów prądu i napięcia zasilającego silnik indukcyjny.
PublicationW niniejszej monografii przedstawiono oryginalne podejście i realizację diagnostyki łożysk silników indukcyjnych przy użyciu metody opartej na pomiarach i analizie iloczynu wartości chwilowych prądu i napięcia zasilającego maszyny. Uzyskane wyniki badań eksperymentalnych na obiektach rzeczywistych okazały się zbieżne z wynikami badań symulacyjnych i potwierdziły, że powstanie uszkodzeń łożysk w silniku skutkuje pojawieniem się...
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Napęd z silnikiem indukcyjnym i 4-gałęziowym falownikiem SiC do turbosprężarek powietrza ogniw paliwowych dużej mocy
PublicationWysoka cena ogniw paliwowych utrudnia ich szerokie zastosowanie w transporcie i przemyśle. Należy szukać możliwości obniżenia ich kosztu również poprzez obniżenie kosztu i zwiększenie wydajności urządzeń pomocniczych ogniwa paliwowego (Balance of the Plant). Autorzy proponują aby w napędzie sprężarki powietrza, zastosować wysokoobrotowy silnik indukcyjny, który jest tańszy od stosowanych obecnie silników PMSM. W referacie zaproponowano...
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The Impact of a New Product’s Novelty and Meaningfulness on its Commercial Performance
Publications new product development (NPD) process encompasses creative actions, so a new product is characterized by two essential dimensions used to describe any creative output – namely novelty and meaningfulness. Therefore, businesses are faced with the questions to what extent and under what market conditions to develop each of these dimensions in order to obtain high new product commercial performance. Based on gaps indentified in the...
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The Implementation of Fuzzy Logic in Forecasting Financial Ratios
PublicationThis paper is devoted to the issue of forecasting financial ratios. The objective of the conducted research is to develop a predictive model with the use of an innovative methodology, i.e., fuzzy logic theory, and to evaluate its effectiveness. Fuzzy logic has been widely used in machinery, robotics and industrial engineering. This paper introduces the use of fuzzy logic for the financial analysis of enterprises. While many current...
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Improving the Efficiency of Semitransparent Perovskite Solar Cell Using Down-Conversion Coating
PublicationPerovskite solar cells (PSCs) have demonstrated exceptional efficiency, yet surpassing theoretical performance limits requires innovative methodologies. Among these, down-conversion techniques are pivotal in reducing optical losses and enhancing energy conversion efficiency. In this study, optical modeling, including a generalized transfer-matrix optical model, was employed to meticulously assess optical losses in semitransparent...
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Image-based numerical modeling of the tensile deformation behavior and mechanical properties of additive manufactured Ti–6Al–4V diamond lattice structures
PublicationThis work concerns the numerical modeling of the deformation process and mechanical properties of structures obtained by the additive method laser power bed fusion (LPBF). The investigation uses diamond structures of Ti–6Al–4V titanium implantation alloy with various relative densities. To model the process of tensile deformation of the materials, geometric models were used, mapping the realistic shape of the examined structures....
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Laser-textured cross-hatched surface topography analysis with evaluation of high-frequency measurement noise
PublicationThe precision of surface roughness determination using ISO 25178 parameters relies on various factors that directly impact the measurement process. In industry applications, the contactless roughness measurement reduces data collection time. However, it introduces several potential errors, including those stemming from the environment. One of the main types of errors encountered during topography analysis is measurement noise,...
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Long-term performance and microbial characteristics of the anammox-enriched granular sludge cultivated in a bench-scale sequencing batch reactor
PublicationThe anammox-enriched granular sludge was successfully formed during the long-term biogranulation experiment lasting over 330 days. The cultivation was conducted at 30 ◦C in a 10-L sequencing batch reactor (SBR) fed with synthetic medium containing ammonia, nitrite and trace elements. The properties of the developed granules were investigated in terms of the biomass activity (including the growth rate of anammox bacteria), size...
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Electric shock hazard in circuits with variable-speed drives
PublicationThe conventional approach to electrical safety under fault condition in typical power systems considers earth fault currents of sinusoidal waveform and frequency of 50/60 Hz. However, in circuits with variable-speed drives, there is earth fault current flow with harmonics, and these harmonics influence the threshold of ventricular fibrillation. The paper presents earth fault current waveforms in circuits with variable-speed drives...
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Acceleration of Electromagnetic Simulations on Reconfigurable FPGA Card
PublicationIn this contribution, the hardware acceleration of electromagnetic simulations on the reconfigurable field-programmable-gate-array (FPGA) card is presented. In the developed implementation of scientific computations, the matrix-assembly phase of the method of moments (MoM) is accelerated on the Xilinx Alveo U200 card. The computational method involves discretization of the frequency-domain mixed potential integral equation using...
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Plasma-Based Deposition and Processing Techniques for Optical Fiber Sensing
PublicationPlasma-based techniques are widely applied for well-controlled deposition, etching or surface functionalization of a number of materials. It is difficult to imagine fabrication of novel microelectronic and optoelectronic devices without using plasma-enhanced deposition of thin films, their selective etching or functionalization of their surfaces for subsequent selective binding of chemical or biological molecules. Depending on...
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Failure analysis of a high-speed induction machine driven by a SiC-inverter and operating on a common shaft with a high-speed generator
PublicationDue to ongoing research work, a prototype test rig for testing high-speed motors/generators has been developed. Its design is quite unique as the two high- speed machines share a single shaft with no support bearings between them. A very high maximum operating speed, up to 80,000 rpm, was required. Because of the need to minimise vibration during operation at very high rotational speeds, rolling bearings were used. To eliminate...
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Two-Row ESPAR Antenna with Simple Elevation and Azimuth Beam Switching
PublicationIn this letter, we propose a two-row electronically steerable parasitic array radiator (ESPAR) antenna designed for direction of arrival (DoA) estimation in Internet of Things (IoT) applications relying on simple microcontrollers. The antenna is capable of elevation and azimuth beam switching using a simple microcontroller-oriented steering circuit and provides 18 directional radiation patterns, which can be grouped in 3 distinctive...
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Detection and Direction-of-Arrival Estimation of Weak Spread Spectrum Signals Received with Antenna Array
PublicationThis paper presents a method for the joint detection and direction of arrival (DOA) estimation of low probability of detection (LPD) signals. The proposed approach is based on using the antenna array to receive spread-spectrum signals hidden below the noise floor. Array processing exploits the spatial correlation between phase-delayed copies of the signal and allows us to evaluate the parameter used to make the decision about the...
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Metoda analizy wielokryterialnej do planowania rozwoju sieci elektroenergetycznej średniego i niskiego napięcia
PublicationW artykule przedstawiono metodę wspomagającą decyzje w zakresie wyboru wariantu przyłączenia odbioru do sieci elektroenergetycznej dystrybucyjnej niskiego napięcia lub średniego napięcia oraz mikrogeneracji do sieci niskiego napięcia. Metodę tą zaimplementowano w skoroszycie kalkulacyjnym Microsoft Excel i zastosowano do analizy złożonych przypadków przyłączenia odbioru lub mikrogeneracji.
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A quasi-2D small-signal MOSFET model - main results
PublicationDynamic properties of the MOS transistor under small-signal excitation are determined by kinetic parameters of the carriers injected into the channel, i.e., the low-field mobility, velocity saturation, mobility at the quiescent-point (Q-point), longitudinal electric field in the channel, by dynamic properties of the channel, as well as by an electrical coupling between the perturbed carrier concentration in the channel and the...
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Nowa metoda diagnostyki stanu technicznego nakładek stykowych
PublicationThe current collection system, which consists of the overhead contact line and a current collector, is particularly important in electric rail vehicles, where their reliability is concerned. Faultless current collection is conditioned not only by suitable construction of these elements but also by their proper maintenance. Retaining permanent electrical contact is essential in DC systems, where current demand is relatively high. In...
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Sterownik PLC jako urządzenie IED zgodne ze standardem IEC 61850
PublicationWraz z rozwojem elektroenergetyki, w stacjach i sieciach elektroenerge- tycznych instalowanych jest coraz więcej cyfrowych urządzeń i układów realizujących złożone funkcje sterowni- cze, nadzorujące i zabezpieczeniowe [1] [2]. Obecnie, większość z tych urządzeń standardowo umożliwia również zdal- ne sterowanie, monitoring i akwizycję danych, wykorzystując jeden z wielu protokołów opracowanych dla prze- mysłowych...
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Heat Dissipation from the Power Cable in the Casing Pipe
PublicationThe current carrying capacity of a power cable determines its ability to carry a specific current and is related to the efficiency of dissipation of heat generated in the cable laid in a specific environment. The studies were conducted in order to determine how the characteristics of the medium around the cable affected its temperature, and thus the ability of the cable to transmit electricity. The experimentation in the lab and...
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Compact High Efficiency and Zero-Emission Gas-Fired Power Plant with Oxy-Combustion and Carbon Capture
PublicationReduction of greenhouse gases emissions is a key challenge for the power generation industry, requiring the implementation of new designs and methods of electricity generation. This article presents a design solution for a novel thermodynamic cycle with two new devices—namely, a wet combustion chamber and a spray-ejector condenser. In the proposed cycle, high temperature occurs in the combustion chamber because of fuel combustion...
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Effect of nitrogen doping on TiOxNy thin film formation at reactive high-power pulsed magnetron sputtering
PublicationThe paper is focused on a study of formation of TiOxNy thin films prepared by pulsed magnetron sputtering of metallic Ti target. Oxygen and nitrogen were delivered into the discharge in the form of reactive gases O2 and N2. The films were deposited by high-power impulse magnetron sputtering working with discharge repetition frequency f = 250 Hz at low (p = 0.75 Pa) and high (p = 10 Pa) pressure. The substrates were on floating...
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Water-mediated influence of a crowded environment on internal vibrations of a protein molecule
PublicationThe influence of crowding on the protein inner dynamics is examined by putting a single protein molecule close to one or two neighboring protein molecules. The presence of additional molecules influences the amplitudes of protein fluctuations. Also, a weak dynamical coupling of collective velocities of surface atoms of proteins separated by a layer of water is detected. The possible mechanisms of these phenomena are described....
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A gap waveguide-based mechanically reconfigurable phase shifter for high-power Ku-band applications
PublicationThis paper presents a novel design of a low-loss, reconfgurable broadband phase shifter based on groove gap waveguide (GGW) technology. The proposed phase shifter consists of a folded GGW and three bends with a few pins forming the GGW and one bend attached to a movable plate. This movable plate allows for adjustments to the folded waveguide length, consequently altering the phase of electromagnetic waves. The advantage of GGW...
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Entire fracture surface topography parameters for fatigue life assessment of 10H2M steel
PublicationIn this paper, the entire fracture surface approach was used to assess an effect of 280,000 h of exploitation under internal pressure of 2.9 MPa and high temperature of 540 °C on the fatigue response of 10H2M (10CrMo9–10) power engineering steel. The mechanical testing was carried out on the hourglass specimens produced from the as-received, unused pipeline and the same material after long-time exploitation. The uniaxial tensile...
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Low-Voltage Low-Power Filters with Independent ω0 and Q Tuning for Electronic Cochlea Applications
PublicationAn acoustic second-order low-pass filter is proposed for filter banks emulating the operation of a human cochlea. By using a special filter structure and an innovative quality (Q)-factor tuning technique, an independent change of the cutoff frequency (ω0) and the Q-factor with unchanged gain at low frequencies is achieved in this filter. The techniques applied result in a simple filter design with low Q-factor sensitivity to component...
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Stability Analysis of Shunt Active Power Filter with Predictive Closed-Loop Control of Supply Current
PublicationThis paper presents a shunt active power filter connected to the grid via an LCL coupling circuit with implemented closed‐loop control. The proposed control system allows selective harmonic currents compensation up to the 50th harmonic with the utilization of a model‐based predictive current controller. As the system is fully predictive, it provides high effectiveness of the harmonic reduction, which is proved by waveforms achieved...
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Controlling nodal displacement of pantographic structures using matrix condensation and interior-point optimization: A numerical and experimental study
PublicationThis study presents an innovative approach for the precise control of nodal displacements in pantographic structures. The method is founded on the Matrix Condensation of Force Method, seamlessly integrated with an Interior Point Optimization algorithm. This combination offers a unique advantage by allowing users to manipulate displaced nodes within a defined coordination domain. Furthermore, this approach introduces the Interior...
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How does stakeholder pressure influence CSR-practices? A construction industry model based on a European sample
PublicationThe stakeholder pressure is one of the most vital powers which determines CSR implementation and can provide organizations with the motivation to adopt corporate social responsibility (CSR) strategy, as the stakeholder theory claims. The current investigation replications Kowalczyk’s (2019) study, who examined the same structure of relations based on the Polish sample. The essence of this replication is to find out whether CSR-...
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Development of biocompatible iron oxide-silicon oxide core-shell nanoparticles as subcellular delivery platform for glucosamine-6-phosphate synthase inhibitors
PublicationIn order to develop the preparation of iron oxide-silica coreshell nanoparticles (CSNPs), thesis deeply explores the cetyltrimethylammonium (CTA+) directed silica coating methods of the oleic-acid capped iron oxide nanoparticles (OA-IONPs) initialized under near-neutral pH conditions. It is demonstrated that the initial alkaline hydrolysis of ethyl acetate in the presence of CTA+ and OA-IONPs induces an unusual ligand exchange...
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Contactless hearing aid designed for infants
PublicationIt is a well known fact that language development through home intervention for a hearing-impaired infant should start in the early months of a newborn baby's life. The aim of this paper is to present a concept of a contactless digital hearing aid designed especially for infants. In contrast to all typical wearable hearing aid solutions (ITC, ITE, BTE), the proposed device is mounted in the infant's bed with any parts of its set-up...
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Diagnosis of Damage in a Steel Tank Model by Shaking Table Harmonic Tests
PublicationDiagnosis of damage in civil engineering structures has recently become an important issue in the safety assessment procedure. Among a number of different approaches, a method of measuring the changes in natural frequencies is one of the most effective indicators of global damage. It has been successfully applied to relatively small. structures, however, the tests on large structures are very difficult and the practical application...
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Design specification management with automated decision-making for reliable optimization of miniaturized microwave components
PublicationThe employment of numerical optimization techniques for parameter tuning of microwave components has nowadays become a commonplace. In pursuit of reliability, it is most often carried out at the level of full-wave electromagnetic (EM) simulation models, incurring considerable computational expenses. In the case of miniaturized microstrip circuits, densely arranged layouts with strong cross-coupling effects make EM-driven tuning...
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Stormwater and snowmelt runoff storage control and flash flood hazard forecasting in the urbanized coastal basin.
PublicationCity of Gdańsk is located in a coastal region where changing climatic conditions increase the frequency of extreme weather events. Developing urbanization affects the hydrology of natural basins by simplification of the drainage system and reduction of infiltration and base flow. Consequently greater runoff rates flow into storm water collection systems, reservoirs and surrounding water bodies. Not only infrastructures of urban...
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Rapid multi-objective optimization of antennas using nested kriging surrogates and single-fidelity EM simulation models
PublicationEver increasing performance requirements make the design of contemporary antenna systems a complex and multi-stage process. One of the challenges, pertinent to the emerging application areas but also some of the recent trends (miniaturization, demands for multi-functionality, etc.), is the necessity of handling several performance figures such as impedance matching, gain, or axial ratio, often over multiple frequency bands. The...
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Sieć sensorowa do rejestracji drgań górnej sieci trakcyjnej w celach diagnostyki eksploatacyjnej
PublicationWraz ze wzrostem prędkości kolejowych pojazdów elektrycznych zwiększają się wymagania utrzymania sieci trakcyjnej w odpowiednim stanie technicznym. Ciągły monitoring i diagnostyka pozwalają wykrywać pogarszającą się jakość odbioru prądu z sieci jezdnej. Jedną z metod jest umieszczenie czujników przyspieszenia na przewodzie jezdnym. Analiza przebiegu przyspieszenia pozwala określić jakość współpracy sieci jezdnej z pantografem....
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Modelowanie matematyczne górnej sieci trakcyjnej dla potrzeb diagnostyki odbieraków prądu
PublicationGórna sieć trakcyjna jest obecnie najbardziej skutecznym sposobem zasilania kolejowych pojazdów elektrycznych. Wzrost prędkości pojazdów zwiększa pobór mocy i wymaga zapewnienia właściwej współpracy odbieraków prądu pojazdów z siecią jezdną. Metody modelowania i projektowania wspomaganego komputerowo dla górnej sieci trakcyjnej są obecnie na całym świecie szeroko rozwijane. W artykule przedstawiono nowy model matematyczny elementów...
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MODELOWANIE MATEMATYCZNE PRZEGRÓD LODOWYCH
PublicationW celu ochrony przed niebezpiecznym zjawiskiem zatoru lodowego opracowano szereg metod, które można podzielić na metody czynne i bierne. Pierwsza grupa obejmuje działania techniczne prowadzące do mechanicznego lub termicznego usuwania lodu i neutralizacji zatorów. Wykorzystuje się w tym calu głównie lodołamacze lub innego typu jednostki pływające. Do metod biernych zalicza się przede wszystkim przegrody lodowe budowane w celu stabilizacji...
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OPTIMIZATION OF ENERGY CONVERSION IN GOLD NANOPARTICLES IRRADIATED BY LIGHT FOR SUSTAINABLE ENERGY APPLICATIONED BY LIGHT FOR SUSTAINABLE ENERGY APPLICATION
PublicationThis study investigates the optimization of light-to-heat conversion in gold nanoparticles under irradiation by continuous- and pulsed-wave laser sources. The conversion process relies on the absorption of electromagnetic energy and the subsequent generation of heat, a phenomenon that is integral to a variety of applications. The photothermal conversion model is based on the Rayleigh-Drude approximation, facilitating predictions...
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The Application of Satellite Image Analysis in Oil Spill Detection
PublicationIn recent years, there has been an increasing use of satellite sensors to detect and track oil spills. The satellite bands, namely visible, short, medium infrared, and microwave radar bands, are used for this purpose. The use of satellite images is extremely valuable for oil spill analysis. With satellite images, we can identify the source of leakage and assess the extent of potential damage. However, it is not yet clear how to...
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ESPAR Antenna-Based WSN Node With DoA Estimation Capability
PublicationIn this paper, we present a low-cost energy-efficient electronically steerable parasitic array radiator (ESPAR) antenna-based wireless sensor network (WSN) node designed for IEEE 802.15.4 standard that is capable of performing direction of arrival (DoA) estimation in real-life outdoor environments. To this end, we propose the WSN node architecture, design and realization that utilizes NXP JN5168 radio frequency (RF) wireless transceiver...
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Effect of Polymerization Statistics on the Electronic Properties of Copolymers for Organic Photovoltaics
PublicationStatistical block copolymers, composed of donor (D) and acceptor (A) blocks, are a novel type of material for organic photovoltaics (OPVs) devices. In particular a new series of polymers based on PBTZT-stat-BDTT-8, recently developed by Merck, offers high solubility in different solvents, and a high power conversion efficiency (PCE) in different device architectures. Although it is known that the electronic properties of these...
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CO2 capture enhancement by metal oxides impregnated coal fly ash: a breakthrough adsorption study
PublicationCoal fired power plants are significant contributors to CO2 emissions and produce solid waste in the form of coal fly ash, posing severe environmental challenges. This study explores the application of dry-impregnated coal fly ash for CO2 capture from gas stream. The modification of coal fly ash was achieved using alkaline earth metal oxides, specifically CaO and MgO, to alter its physical and chemical properties. Characterization...
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A new deterministic PSO algorithm for real-time systems implemented on low-power devices
PublicationThe paper presents a novel, deterministic particle swarm optimization (PSO) algorithm, facilitating its implementation in low-power application specific integrated circuits (ASIC) realized in CMOS technology. The PSO algorithms are commonly used in a variety of optimization problems. They allow to search for a global extreme in a selected fitness function, which is used for numerical modeling of specific optimized problems. The...
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Variable‐fidelity modeling of antenna input characteristics using domain confinement and two‐stage Gaussian process regression surrogates
PublicationThe major bottleneck of electromagnetic (EM)-driven antenna design is the high CPU cost of massive simulations required by parametric optimization, uncertainty quantification, or robust design procedures. Fast surrogate models may be employed to mitigate this issue to a certain extent. Unfortunately, the curse of dimensionality is a serious limiting factor, hindering the construction of conventional data-driven models valid over...
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Design-oriented modeling of antenna structures by means of two-level kriging with explicit dimensionality reduction
PublicationThe employment of full-wave electromagnetic (EM) analysis is a practical necessity in the design of contemporary antenna structures. This is because simpler models are generally not available or of limited accuracy. At the same time, EM-based design is computationally expensive. Consequently, the ways of accelerating tasks such as parametric optimization or uncertainty quantification have to be sought. A possible workaround that...
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Electrohydrodynamic Flow Patterns in a Narrow Electrostatic Precipitator with Longitudinal Wire Electrode for Various Electrode Geometries
PublicationRecently narrow electrostatic precipitators (ESPs) have become a subject of interest because of their possible application in diesel engines. In this paper results of 2-dimensional (2D) Particle Image Velocimetry (PIV) measurements of the flow patterns in a narrow ESP for a various electrode geometries are presented. The PIV measurements were carried out in the observation plane that is perpendicular to the ESP duct. The ESP was...
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Expedited Yield Optimization of Narrow- and Multi-Band Antennas Using Performance-Driven Surrogates
PublicationUncertainty quantification is an important aspect of engineering design, also pertaining to the development and performance evaluation of antenna systems. Manufacturing tolerances as well as other types of uncertainties, related to material parameters (e.g., substrate permittivity) or operating conditions (e.g., bending) may affect the antenna characteristics. In the case of narrow- or multi-band antennas, this usually leads to...
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AUTOMATED SYSTEM FOR FLUCTUATION ENHANCED GAS SENSING
PublicationResistance gas sensors exhibit random phenomena (resistance noise) which can be utilized to improve gas sensitivity and selectivity. That new emerging technique has to be investigated to recognize optimal parameters for gas detection. It means that a measurement system has to have ability of numerous parameters adjustment (e.g., sampling frequency, heater voltage, polarization current, voltage noise amplification). That fact induced...
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The influence of electromagnetic pollution on living organisms – historical trends and forecasting changes
PublicationCurrent technologies have become a source of omnipresent electromagnetic pollution from generated electromagnetic fields and resulting electromagnetic radiation. In many cases this pollution is much stronger than any natural sources of electromagnetic fields or radiation. Wireless and radio communication, electric power transmission or devices in daily use such as smartphones, tablets and portable computers every day expose people...
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Cross-talk Between the Heart and Arteries in Older 65+ Adults
PublicationRegulatory synchronization between the heart and the arterial walls is essential for optimal blood delivery to tissues. We investigated functional coherence between heart rhythm and aortic wall compliance in 30 volunteers aged 65 – 74. ECG and carotid and iliac pulse-wave were recorded and digitized at 2 kHz. Carotid-femoral pulse-wave transit time (cfTT) which reflex aortic compliance was assessed using the intersecting tangent...