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Electrical safety in low-voltage DC microgrids with B-type residual current devices
PublikacjaResidual current devices (RCDs) are most popular devices used in low-voltage installations for protection against electric shock and fire. In cases of high risk of electric shock the application of RCDs is mandatory. Currently, the spread of local direct current (DC) microgrids is widely considered. This creates new challenges for protective systems, in particular those based on RCDs. The main purpose of the research is to test...
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Analysis of exhaled breath for dengue disease detection by low-cost electronic nose system
PublikacjaThis paper presents a procedure and a set-up of an electronic nose system analyzing exhaled breath to detect the patients suffering from dengue – a mosquito-borne tropical disease. Low-power resistive gas sensors (MiCS-6814, TGS8100) were used to detect volatile organic compounds (VOCs) in the exhaled breath. The end-tidal phase of patients exhaled breath was collected with a BioVOCTM breath sampler. Two strategies were assessed...
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Prototype design and development of low-load-roof photovoltaic modules for applications in on-grid systems
PublikacjaFour prototypes of lightweight photovoltaic modules for applications in on-grid systems have been designed, developed, manufactured and tested for compliance with relevant IEC standards. Selected, commercially available materials characterized by thermogravimetry, differential scanning calorimetry, dilatometry, scanning electron microscopy and nanoindentation technique were used in frameless, adhesively-bonded sandwich-structures...
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Low-cost multi-objective design of compact microwave structures using domain patching
PublikacjaA good compromise between size and electrical performance is an important design consideration for compact microwave structures. Comprehensive information about size/performance trade-offs can be obtained through multi-objective optimization. Due to considerable electromagnetic (EM) cross-couplings in highly compressed layouts, the design process has to be conducted at the level of high-fidelity EM analysis which is computationally...
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Determination of refractive index dispersion using fiber-optic low-coherence Fabry–Perot interferometer: implementation and validation
PublikacjaWe present the implementation and validation of low-coherence Fabry–Perot interferometer for refractive index dispersion measurements of liquids. A measurement system has been created with the use of four superluminescent diodes with different optical parameters, a fiber-optic coupler and an optical spectrum analyzer. The Fabry–Perot interferometer cavity has been formed by the fiber-optic end and mirror surfaces mounted on a micromechanical...
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Assessment of Thermal Stresses in Asphalt Mixtures at Low Temperatures Using the Tensile Creep Test and the Bending Beam Creep Test
PublikacjaThermal stresses are leading factors that influence low-temperature cracking behavior of asphalt pavements. During winter, when the temperature drops to significantly low values, tensile thermal stresses develop as a result of pavement contraction. Creep test methods can be suitable for the assessment of low-temperature properties of asphalt mixtures. To evaluate the influence of creep test methods on the obtained low-temperature...
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H2O˙+ and OH+ reactivity versus furan: experimental low energy absolute cross sections for modeling radiation damage
PublikacjaRadiotherapy is one of the most widespread and efficient strategies to fight malignant tumors. Despite its broad application, the mechanisms of radiation-DNA interaction are still under investigation. Theoretical models to predict the effects of a particular delivered dose are still in their infancy due to the difficulty of simulating a real cell environment, as well as the inclusion of a large variety of secondary processes. This...
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Low-cost multi-objective optimization and experimental validation of UWB MIMO antenna
PublikacjaPurpose–The purpose of this paper is to validate methodologies for expedited multi-objective designoptimization of complex antenna structures both numerically and experimentally.Design/methodology/approach–The task of identifying the best possible trade-offs between theantenna size and its electrical performance is formulated as multi-objective optimization problem.Algorithmic frameworks are described for finding Pareto-optimal...
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Modeling of low calorific gas burning in a deficient oxygen environment and high-temperature oxidizer
PublikacjaThe experimental research will be performed using the experimental facility with a combustion chamber. The oxygen concentration in combustion oxidizers will be varied from 21% by volume (normal) air to 2%. The test combustion chamber will be fed with propane or methane as the reference fuel, then with low calorific fuels as test gases obtained by mixing various combustible components, e.g. H2, CH4, CO, and neutral gases, e.g. N2,...
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Upgrading low value-added activities in global value chains: a functional specialisation approach
PublikacjaThis paper aims to identify patterns of functional specialisation (FS) in global value chains (GVCs) and determinants of upgrading them for selected Central Eastern European (CEE) economies. By combing the World Input-Output Database with data on occupations, we reveal a new FS pattern among subgroups of CEEs. Poland and Slovakia have an unfavourable GVC position and specialise in low value-added fabrication function. In contrast,...
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Low-cost multi-objective optimization of antennas using Pareto front exploration and response features
PublikacjaIn the paper, a procedure for low-cost multi-objective optimization of antenna structures is presented. Our approach is based on exploration of the Pareto front representing the best possible trade-offs between conflicting objectives, here, the structure size and its electrical performance. Starting from the design representing the best in-band reflection level, subsequent Pareto-optimal designs are identified through local constrained...
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PROBLEMS OF THE STARTING AND OPERATING OF HYDRAULIC COMPONENTS AND SYSTEMS IN LOW AMBIENT TEMPERATURE (PART IV) MODELLING THE HEATING PROCESS AND DETERMINING THE SERVICEABILITY OF HYDRAULIC COMPONENTS DURING THE STARTING-UP IN LOW AMBIENT TEMPERATURE
PublikacjaDesigners of hydraulically driven machines and devices are obliged to ensure during design process their high service life with taking into account their operational conditions. Some of the machines may be started in low ambient temperature and even in thermal shock conditions (due to delivering hot working medium to cold components). In order to put such devices into operation appropriate investigations, including experimental...
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Quasi-discrete modelling of PMSM phase currents in drives with low switching-to-fundamental frequency ratio
PublikacjaThis study proposes a new quasi-discrete approach to modelling the permanent magnet synchronous motor (PMSM). The quasi-discrete modelling reflects the impact of continuous rotor movement, which takes place during a control cycle, on the shape of motor current waveforms. This provides much improvement in current modelling accuracy under inverter low switching-to-fundamental frequency operation. The proposed approach may be used...
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Recent progress in ultra-low formaldehyde emitting adhesive systems and formaldehyde scavengers in wood-based panels: a review
PublikacjaTraditional wood-based panels are produced with synthetic, formaldehyde-based adhesives, commonly made from fossil-derived constituents, such as urea, phenol, melamine, etc. Along with their numerous advantages, such as chemical versatility, high reactivity and excellent adhesive performance, these adhesives are characterized by certain problems, connected with the hazardous volatile organic compounds (VOCs), mostly free formaldehyde...
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Inhomogeneity of low-noise wearing courses evaluated by tire/road noise measurements using the close-proximity method
PublikacjaPerforming numerous analyses of tire/road noise measurements on low-noise pavements during the last several years, the authors observed significant inhomogeneity of the wearing course in numerous cases, while similar problems were almost non-existent when dense pavements were measured. Three main causes of low-noise pavement inhomogeneity can be defined. The first one is imperfections in the technology used for asphalt mix production...
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Application of thin diamond films in low-coherence fiber-optic Fabry Pérot displacement sensor
PublikacjaThe novel fiber-optic low coherence sensor with thin diamond films is demonstrated. The undoped and boron-doped diamond films were elaborated by the use of the microwave plasma enhanced chemical vapor deposition (μPE CVD) system. The optical signal from the Fabry–Pérot cavity made with the application of those thin films is sensitive to displacement. The sensor characterization was made in the range of 0–600 μm. The measurements...
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Effect of bitumen characteristics obtained according to EN and Superpave specifications on asphalt mixture performance in low-temperature laboratory tests
PublikacjaThe paper aims to identify those characteristics of bitumen which have the greatest impact on asphalt mixture low-temperature performance. It was observed that stiffness and m-value of bitumen from BBR test were moderately related to stiffness and m-value of asphalt mixture obtained from 3 PB test. Simultaneously those rheological properties significantly impact on cryogenic stresses induced during TSRST test. The multiple regression...
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Fatigue life improvement using low transformation temperature weld material with measurement of residual stress
PublikacjaWelding processes often produce high levels of tensile residual stress. Low transformation temperature (LTT) welding wires utilise phase transformation strains to overcome the thermal contraction of a cooling weld. In this paper, the residual stress within each weld was quantified using the milling/strain gauge method, being the strain change measured as the weldment was milled away. The fatigue tests were conducted under uniaxial...
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Biochemical assays of intensified methane content in biogas from low-temperature processing of waste activated sludge
PublikacjaAnaerobic digestion (AD) is implemented as an important ‘waste to energy’ approach for converting organic-rich byproducts such as sewage sludge into biogas and nutrient-rich digestate. Sewage sludge consists of primary sludge and waste activated sludge (WAS), and low biodegradability of WAS limits methane production. This study presents the influence of the low-temperature pretreatment (LT-PT) of WAS on the efficiency of AD. Different...
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Experimental Study of Flow Rate in Hydraulic Satellite Motor with the Rotating Case at a Low Constant Rotational Speed
PublikacjaIn this article was described the methodology for the experimental study of flows in the prototype of a satellite hydraulic motor with a rotating body. The experimental tests of the motor were carried out at a low constant rotational speed in a wide range of pressure drop in this motor. The constant rotational speed of the motor was kept by a worm gear. Based on the test results, the leakage characteristics in the flat gaps of...
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Sestaveni Smerne Krivky Modulu Tuhosti Pro Zkoumani Nizkotrplotnich Vlastnosti (Developing of Stiffness Master Curve for Analysis of Low Temperature Properties)
PublikacjaV prispevku je predstaven novy postup pro sestrojeni smernych tuhostnich krivek. Nizkoteplotni vlastnosti asfaltove smesi byly stanoveny za vyuziti zkousky dotvarovani pri tribodovem ohybu. Motivem tohoto vyzkumu je skutecnost, ze metody hodnoceni nizkoteplotniho chovani asfaltovych smesi, nove zavedenych v Polsku, nejsou dostatecne. V zaveru jsou prezentovany smerne krivky tuhosti beznych asfaltovych smesi vyuzivanych v Polsku.
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Initial evaluation of commercial optical CT‐based 3D gel dosimeter
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Dissolution of Nb-doped hydroxyapatite prepared via low-temperature mechanochemical method: Spectroscopy studies
PublikacjaCalcium phosphate glass ceramics with nominal hydroxyapatite stoichiometry doped with niobium were synthesized using simple as well as low-temperature mechanochemical method and then in the form of compressed pellet were submitted to the static dissolution process in distilled water for one month. The results of structural analysis, performed mainly on the base of spectroscopic methods such as: infrared absorption spectroscopy,...
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Emerging oxidized and defective phases in low-dimensional CrCl3
PublikacjaTwo-dimensional (2D) magnets such as chromium trihalides CrX3 (X ¼ I, Br, Cl) represent a frontier for spintronics applications and, in particular, CrCl3 has attracted research interest due its relative stability under ambient conditions without rapid degradation, as opposed to CrI3. Herein, mechanically exfoliated CrCl3 flakes are characterized at the atomic scale and the electronic structures of pristine, oxidized, and defective...
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Development of low noise CCD readout front-end
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Low-Cost Embedded Control System for Environmental Monitoring
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Biological hazards in low noise, poroelastic road surfaces
PublikacjaDrainage pavements as well as poroelastic pavements ("PERS") are a very efficient way to decrease traffic noise by reducing tire/road noise at the source as well as noise propagation over the road surface. Many noise generating mechanisms at the tire/road interface are very much reduced by road porosity (pipe resonance, "air pumping", Helmholtz resonance and the horn effect). A well-designed porous or poroelastic road surface may...
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Low energy electron mass stopping power in H2
PublikacjaWe present experimental mass stopping powers of electrons in gaseous H2 obtained with a newly developed electron time-of-flight spectrometer, for the incident electron energy range of 10eV to 25eV. In our procedure the average energy loss is derived from our conversion of measured electron time-of-flight spectra into equivalent electron energy loss spectra so as to obtain the values of mass stopping power for electron scattering...
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Low-coherence photonic method of electrochemical processes monitoring
PublikacjaWe present an advanced multimodality characterization platform for simultaneous optical and electrochemical measurements of ferrocyanides. Specifcally, we combined a fber-optic Fabry– Perot interferometer with a three-electrode electrochemical setup to demonstrate a proof-ofprinciple of this hybrid characterization approach, and obtained feasibility data in its monitoring of electrochemical reactions in a boron-doped diamond flm...
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Low-cost handheld multiprobe reflectometer for the ism band
PublikacjaW artykule przedstawiona została procedura oraz działający model taniego miernika współczynnika odbicia na pasmo ISM. Koncepcja modelu oparta jest o reflektometr z multi próbkowaniem oraz wykorzystanie zintegrowanego detektora mocy firmy Analog Devices. Prototypowy miernik z interfejsem został zbudowany. Wyniki symulacji oraz eksperymentu zostały przedstawione.
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Optical low-coherence interferometry for selected technical applications
PublikacjaW artykule przedstawiono teoretyczne podstawy optycznej interferometrii niskokoherentnej i przedyskutowano jej unikatowe właściwości. Opisano w nim opracowany przez autorów system OCT przeznaczony do badań strukturalnych materiałów technicznych. Badania te obejmują także zmiany stanu polaryzacji promieniowania rozproszonego w badanym obiekcie. W artykule zawarto wyniki badań wybranych materiałów silnie rozpraszających promieniowanie...
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A High-Efficient Low-Voltage Rectifier for CMOS Technology
PublikacjaA new configuration of rectifier suiting CMOS technology is presented. The rectifier consists of only two nchannel MOS transistors, two capacitors and two resistors; for this reason it is very favourable in manufacturing in CMOS technology. With these features the rectifier is easy to design and cheap in production. Despite its simplicity, the rectifier has relatively good characteristics, the voltage and power efficiency, and...
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Criteria for selection of working fluid in low-temperature ORC
PublikacjaThe economics of an ORC system is strictly linked to thermodynamic properties of the working fluid. A bad choice of working fluid could lead to a less efficient and expensive plant/generation unit. Some selection criteria have been put forward by various authors, incorporating thermodynamic properties, provided in literature but these do not have a general character. In the paper a simple analysis has been carried out which resulted...
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Dissociation of 2-oxopropanoic acid by low energy electrons
PublikacjaElectron attachment to molecular target can lead to a variety of negative fragment ions. We experimentally probe the main dissociative electron attachment (DEA) channels in 2-oxopropanoic acid (CH3 - CO - COOH) - an important trace component in the Earth's atmosphere. In our studies we utilise nearly mono-energetic electrons at electron energies from 0 eV up to 15 eV.
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Analog multiplier for a low-power integrated image sensor
PublikacjaArtykuł przedstawia nowe podejście do projektowania tanich niskomocowych zintegrowanych sensorów optycznych. W odróżnieniu od wcześniej stosowanych rozwiązań opartych na masowym przetwarzaniu równoległym, zaproponowany mnożnik macierzowy charakteryzuje się korzystniejszymi cechami. Proponowane rozwiązanie, chociaż mniej elastyczne w sensie liczby możliwych do zaimplementowania algorytmów wstępnej obróbki obrazu, cechuje się znaczącą...
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Analog multiplier for a low-power integrated image sensor
PublikacjaArtykuł przedstawia nowe podejście do projektowania tanich niskomocowych zintegrowanych sensorów optycznych. W odróżnieniu od wcześniej stosowanych rozwiązań opartych na masowym przetwarzaniu równoległym, zaproponowany mnożnik macierzowy charakteryzuje się korzystniejszymi cechami. Proponowane rozwiązanie, chociaż mniej elastyczne w sensie liczby możliwych do zaimplementowania algorytmów wstępnej obróbki obrazu, cechuje się znaczącą...
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Low sulphur coal combustion - Optimisation of boiler tunings.
PublikacjaBadaniami w ramach projektu objęto przede wszystkim kotły parowe oraz układy wspomagające, takie jak: podajniki węgla, młyny, wentylatory, instalacje oczyszczania spalin. Badania eksperymentalne przeprowadzono na obiektach Elektrociepłowni Kraków, natomiast obliczenia numeryczne zostały wykonane przez Politechnikę Wrocławska we współpracy z firmą R&D EDF. Sformułowano szereg konkretnych wytycznych do przeprowadzenia niezbędnych...
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Multiple-scattering and electron-uracil collisions at low energies
PublikacjaDyskutowany jest związek dwóch znanych metod w teorii rozpraszania elektronów na cząsteczkach : potencjałów zerowego promieniu i metody potencjałów "muffin-tin". Rozwój obu metod pozwala na stworzenie nowej techniki obliczenia parcjalnych faz i przekrojów czynnych w nazwanej teorii. Technika ta ma zastosowanie do zagadnienia dotyczącego układu elektron-uracil.
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Low-Molecular-Weight Aldehyde Inhibitors of Cathepsin G
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Influence of the Adsorption Bed Composition on the Low-Pressure Fluidization
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Smart Graphite–Cement Composites with Low Percolation Threshold
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Development of low noise CCD readout front-end
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Low-Energy Tautomers and Conformers of Neutral and Protonated Arginine
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Low-Sulphur Marine Fuels—Panacea or a New Threat?
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Low-Cost Underwater Communication System: A Pilot Study
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Assessing pathways into a low carbon and climate responsible Gdansk
PublikacjaA basic question today is the sense of the use new ideas in shaping Polish cities- not as technologically advanced as others. The key is to understand good practices in designing and implementing new approaches. The comparative research Glasgow and Gdansk has been undertaken by Gdansk Development Agency in Jan 2014
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Hydrogen degradation of high strength low alloyed steels.
PublikacjaBadano wpływ polaryzacji katodowej na własności stali węglowej, stali o podwyższonej i wysokiej wytrzymałości metodą stałego powolnego odkształcania.Stwierdzono, że stopień kruchości wodorowej każdej z badanych stali zależał od stężenia wodoru dyfuzyjnego.
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An advanced low-cost sensorless induction motor drive
PublikacjaW artykule przedstawiono układ sterowania silnikiem asynchronicznym klatkowym pracujący bez pomiaru prędkości obrotowej. Układ zrealizowano na tanim procesorze stałoprzecinkowym. aspekty praktyczne realizacji układu rozpatrzono na podstawie uzyskanych wyników z symulacji i eksperymentu.
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Sensorless multiscalar controls of induction motor at low speed
PublikacjaW artykule przedstawiono zastosowanie obserwatora prędkości w dwóch różnych układach sterowania multiskalarnego silnikiem klatkowym. Pierwszy układ bazuje na prądzie stojana i strumieniu wirnika, natomiast drugi nowy układ wykorzystuje zmienne prąd stojana i strumień stojana. Zamieszczono wyniki badań symulacyjnych i eksperymentalych w układzie ze sterowaniem na procesorze SHARC.
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Design of low noise preamplifers for characterization of LSCO bolometers
PublikacjaW artykule przedstawiono wymagania stawiane układom do pomiaru szumów bolometrów. Ze względu na niski poziom mierzonych szumów układy te wymagają zastosowania niskoszumnych przedwzmacniaczy i układów ustalających punkt pracy badanych detektorów. Omówiono konstrukcje dwóch przedwzmacniaczy z zintegrowanymi układami polaryzacji. Przedstawiono wyniki pomiarów szumów w zakresie częstotliwości 10-90Hz. Przedstawiono możliwości ulepszenia...