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Influence of hydrogen on a nanocrystalline high-entropy oxide with application potential in hydrogen technologies
PublicationThe influence of hydrogen on a (Co0⋅2Cu0⋅2Mg0⋅2Ni0⋅2Zn0.2)O HEO with a rock salt structure was studied. Two forms of this HEO (nanopowder and sinter) were prepared via mechanochemical synthesis (MS) and additional heat treatment, respectively. The chemical stability of the synthesized samples in a pure hydrogen atmosphere was investigated using Sievert’s technique. High-pressure hydrogenation at 250 ◦C had no noticeable effect...
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Opracowanie ekspertyzy dotyczącej przyczyn pękania łopatek wirnika SP turbiny PG1 typu 13UP55
PublicationZakres badań i analiz dotyczył ustalenia przyczyn pękania elementów łopatek wirnika SPA5 turbiny TG1 typu 13UP55 obejmował: 1. wykonanie badań składu chemicznego stali, z której wykonano łopatki dostarczone przez Zleceniodawcę dwoma metodami, 2. badania mikroobszarów zniszczenia łopatek na mikroskopie elektronowym skaningowym z mikroanalizatorem EDS, 3. badania metalograficzne makroskopowe i mikroskopowe fragmentów...
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Fast-response optoelectronic detection of explosives’ residues from the nitroaromatic compounds detonation: field studies approach
PublicationWe are presenting an application of optoelectronic nitrogen dioxide (NO2) analyzer based on cavity enhanced absorption spectroscopy in the detection of traces of explosives after detonation. It has been shown that the analyzer using blue-violet laser is able to detect explosive residues after the detonation of various amounts of nitroaromatic compounds (75g-1kg) with higher efficiency than the HPLC soil sample testing equipment,...
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PROPELLER INVESTIGATIONS BY MEANS OF NUMERICAL SIMULATION
PublicationThe analyses of hydroacoustics are of high interest at the moment due to strong impact of hydroacoustic phenomena on marine environment; the noises, generated e.g. by marine traffic, may be harmful for sea life. The analyses presented here are focused on one of main sources of noises generated by ships, i.e. cavitating propeller. The goal of the work is the assessment of the cavitation phenomenon, carried out with the standard...
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Experiences from operation of various expansion devices in small scale ORC
PublicationThe main aim of this paper was to present various expansion devices for an application in the small scale ORC system. The investigations were carried out in two parallel directions. One direction was to design and construct a device dedicated to the analyzed ORC system. The second direction was to adapt existing expansion devices for the needs of the analyzed ORC system. Four various devices were described and presented together...
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Air flow phenomena in the model of the blind drift
PublicationIn the presented paper, Particle Image Velocimetry (PIV) has been used to investigate flow pattern and turbulent structure in the model of blind drift. The presented model exist in mining, and has been analyzed to resolve ventilation issues. Blind region is particularly susceptible to unsafe methane accumulation. The measurement system allows us to evaluate all components of the velocity vector in channel cross-section simultaneously....
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Imidazole-Based Lithium Salt LiHDI as a Solid Electrolyte Interphase-Stabilising Additive for Lithium-Conducting Electrolytes
PublicationLithium salt LiHDI (lithium 4,5-dicyano-2-(n-heptafluoropropyl)imidazolide) is proposed as a solid electrolyte interphase-stabilising additive for lithium-ion batteries, which can be added in a smaller amount than fluoroethylene carbonate (FEC) and vinylene carbonate (VC) additives. Electrolytes containing either lithium 4,5-dicyano-2-(trifluoromethyl)imidazolide (LiTDI) or battery-standard LiPF6 were tested with various amounts...
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Heuristic scheduling algorithms for uniform load of computer system
PublicationW pracy zaprezentowano opracowany heurystyczny algorytm szeregowania zadań UNILO (ang. UNIform LOad - jednakowe obciążenie), umożliwiający redukcję całkowitego zapotrzebowania na moc obliczeniową systemu komputerowego bez pogarszania jego wydajności. Algorytm ten realizuje takie przydzielenie zadań obliczeniowych do poszczególnych jednostek (procesorów), aby zapewnić ich jednakowe obciążenie. Opracowany algorytm został zweryfikowany...
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Degradation of the Concrete Railway Track Bed Located in the Vicinity of the Loading Wharf
PublicationThe following article describes the damages of the concrete railway track bed at the place of unloading petroleum products located in the immediate vicinity of the cargo berth. The concrete of the track bed has been a subject to degradation as a result of many years of exploitation resulting, inter alia, in its cyclical flooding of petroleum products during the unloading and loading of rail tankers. Repairs carried out in the previous...
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Projektowanie oraz implementacja cyfrowego multiefektu gitarowego z wykorzystaniem procesora sygnałowego
PublicationW artykule został przedstawiony proces projektowania i realizacji cyfrowego multiefektu gitarowego z wykorzystaniem procesora sygnałowegoTMS320C5535 firmy Texas Instruments, dla którego oprogramowanie napisano w języku C. Omówiono zasady działania oraz algorytmy wybranych efektów dźwiękowych, które zostały zaimplementowane w procesorze sygnałowym. Zaprojektowano również uniwersalny moduł wejściowy zawierający wzmacniacz z regulowanym...
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Vision-based parking lot occupancy evaluation system using 2D separable discrete wavelet transform
PublicationA simple system for rough estimation of the occupancy of an ad-hoc organized parking lot is presented. A reasonably simple microprocessor hardware with a low resolution monochrome video camera observing the parking lot from the location high above the parking surface is capable of running the proposed 2-D separable discrete wavelet transform (DWT)-based algorithm, reporting the percentage of the observed parking area occupied by...
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MOBILITY OF SHALE DRILL CUTTINGS CONSTITUENTS
PublicationThis study focuses on the abundance and mobility of metals and trace elements from shale drill cuttings into the water, being the main component of hydraulic fracturing fluid. The relationship between composition of the shale rock and the potential element release during standard water-based leaching tests was characterized by means of X-Ray Fluorescence spectroscopy (XRF). The XRF analysis confirmed the assumption of shales constituents...
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Relations between magnetosonic perturbations as an indicator of a magnetosonic exciter and equilibrium parameters of a plasma
PublicationThe thermodynamic relations between perturbation of pressure and pertur- bation of mass density and between components of velocity which specify a magnetosonic wave are theoretically studied. A planar flow with the wave vec- tor forming a constant angle with the equilibrium magnetic field is investigated. The theory considers deviation from the adiabaticity of a flow due to some kind of heating–cooling function and thermal conduction...
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Design of Resilient Vehicle-to-Infrastructure Systems
PublicationVehicular ad hoc networks (VANETs) have recently gained noticeable attention due to advantages in improving road traffic safety, shaping the road traffic and providing infotainment opportunities to travellers. However, transmission characteristics following from the IEEE 802.11p standard and the high mobility of VANET nodes remarkably reduce the lifetime, reach and capacity of wireless links, and often lead to simultaneous disruptions...
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Wykorzystanie teorii ograniczeń do realizacji zasad koncepcji Lean
PublicationZłożone i dynamiczne otoczenie wymaga nieustannych zmian i doskonalenia działalności organizacji oraz rekonfiguracji procesów realizowanych w sieciach organizacji. Przed organizacjami stawiane są liczne wyzwania. Wymagania rynku powodują, że za pożądane metacechy organizacji można uznać elastyczność, jakość oraz innowacyjność. Ponadto wewnętrzne naciski na poprawę efektywności funkcjonowania organizacji wymagają ograniczania kosztów...
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Rule-Based Model for Selecting Integration Technologies for Smart Cities Systems
PublicationThe aim of this article is to present the stages of development for an information technology integration model for the design of systems for smart cities. The Introduction explains the need for integration technologies and presents a model for selecting integration technologies and the conditions for its use in designing smart cities systems. Then two verification stages of the presented model are discussed. In the first stage,...
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Feature Reduction Using Similarity Measure in Object Detector Learning with Haar-like Features
PublicationThis paper presents two methods of training complexity reduction by additional selection of features to check in object detector training task by AdaBoost training algorithm. In the first method, the features with weak performance at first weak classifier building process are reduced based on a list of features sorted by minimum weighted error. In the second method the feature similarity measures are used to throw away that features...
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Super-resolved Thermal Imagery for High-accuracy Facial Areas Detection and Analysis
PublicationIn this study, we evaluate various Convolutional Neural Networks based Super-Resolution (SR) models to improve facial areas detection in thermal images. In particular, we analyze the influence of selected spatiotemporal properties of thermal image sequences on detection accuracy. For this purpose, a thermal face database was acquired for 40 volunteers. Contrary to most of existing thermal databases of faces, we publish our dataset...
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Numerical and experimental investigation of guided ultrasonic wave propagation in non-uniform plates with structural phase variations
PublicationThe article presents the results of numerical and experimental investigations of guided wave propagation in aluminum plates with variable thickness. The shapes of plate surfaces have been specially designed and manufactured using a CNC milling machine. The shapes of the plates were defined by sinusoidal functions varying in phase shift, which forced the changes in thickness variability alongside the propagation path. The main aim...
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Tensile modulus of human orbital wall bones cut in sagittal and coronal planes
PublicationIn the current research, 68 specimens of orbital superior and/or medial walls taken from 33 human cadavers (12 females, 21 males) were subjected to uniaxial tension untill fracture. The samples were cut in the coronal (38 specimens) and sagittal (30 specimens) planes of the orbital wall. Apparent density (ρapp), tensile Young’s modulus (E-modulus) and ultimate tensile strength (UTS) were identified. Innovative test protocols were...
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Experimental and Numerical Investigation of Mechanical Properties of Lightweight Concretes (LWCs) with Various Aggregates
PublicationHigh requirements for the properties of construction materials and activities directed at environment protection are reasons to look for new solutions in concrete technology. This research was directed at solutions affecting the reduction of energy consumption and CO2 emissions. The use of lightweight concretes (LWCs) allows one to meet both conditions at the same time. The purpose of the research presented in this paper was to...
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A shear stress micromodel of urinary tract infection by the Escherichia coli producing Dr adhesin
PublicationIn this study, we established a dynamic micromodel of urinary tract infection to analyze the impact of UT-segment-specific urinary outflow on the persistence of E. coli colonization. We found that the adherence of Dr+ E. coli to bladder T24 transitional cells and type IV collagen is maximal at lowest shear stress and is reduced by any increase in flow velocity. The analyzed adherence was effective in the whole spectrum of physiological...
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Release of Encapsulated Bioactive Compounds from Active Packaging/Coating Materials and Its Modeling: A Systematic Review
PublicationThe issue of achieving controlled or targeted release of bioactive compounds with specific functional properties is a complex task that requires addressing several factors, including the type of bioactive, the nature of the delivery system, and the environmental conditions during transportation and storage. This paper deals with extensive reporting for the identification of original articles using Scopus and Google Scholar based...
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Dynamic coloring of graphs
PublicationDynamics is an inherent feature of many real life systems so it is natural to define and investigate the properties of models that reflect their dynamic nature. Dynamic graph colorings can be naturally applied in system modeling, e.g. for scheduling threads of parallel programs, time sharing in wireless networks, session scheduling in high-speed LAN's, channel assignment in WDM optical networks as well as traffic scheduling. In...
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Carboxy derivative of dioxydiphenylpropane diglycydyl ether monomethacrylate as an addtive for composites
PublicationThe modifier of composites was used in the presence of polyetylene polyamine. Physico-mechanical properties and chemical stability of coatings thus obtained were analyzed.
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Miernictwo elektryczne na politechnice w Gdańsku w latach 1904–1945
PublicationPolitechnika Gdańska została utworzona w 1904 roku. Działalność uczelni nierozerwalnie związana była z losami Gdańska, dlatego w jej historii do 1945 roku można wyróżnić trzy okresy: pruski, Wolnego Miasta Gdańska oraz czasy drugiej wojny światowej. Od początku, jednym z ważniejszych kierunków nauczania była elektrotechnika. Postęp w elektrotechnice nie był możliwy bez rozwoju miernictwa elektrycznego, dlatego przez cały czas działania...
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Study of the Resistance to Influence of Aggressive Liquids on Concrete with Lightweight Aggregate
PublicationThe corrosion of the structure of concrete caused by the aggressive external environment is one of the main problems that can reduce the durability of buildings. The paper analyzes the influence of the type of component on selected properties of lightweight concrete (LWC) exposed to aggressive liquids. When lightweight concrete containing porous aggregates is used, the influence of an aggressive environment may be of particular...
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The Analysis of Container Vessel Service Efficiency in the Aspect of Berth and Handling Equipment Usage in Polish Ports
PublicationThe paper analyses the efficiency of container vessel service in Polish container terminals taking under considerations different berth layouts and handling equipment.
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Morphology and degradation of polyurehanes in different environments.
PublicationW pracy przedstawiono wyniki badań degradacji poli(estro-uretanów) (PEsUA i PEsUB) oraz poli(etero-uretano-mocznika)(PEtUU) w roztworach buforowych o zmiennym pH (168 godz., 70 oC), w środowisku trypsyny (37 oC, 1 m-c), Aspergillys niger (12 m-cy), kompoście z osadem czynnym (12 m-cy) i w wodzie morskiej (12 m-cy). Analizowano zmiany w morfologii i właściwościach fizykomechanicznych. Ustalono następujące sekwencje w zmianach zależności...
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Molecular transformation of dissolved organic matter in manganese ore-mediated constructed wetlands for fresh leachate treatment
PublicationThe organic matter (OM) and nitrogen in Fresh leachate (FL) from waste compression sites pose environmental and health risks. Even though the constructed wetland (CW) can efficiently remove these pollutants, the molecular-level transformations of dissolved OM (DOM) in FL remain uncertain. This study reports the molecular dynamics of DOM and nitrogen removal during FL treatment in CWs. Two lab-scale vertical-flow CW systems were...
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Determination of parent and methylated polycyclic aromatic hydrocarbons in water samples by dispersive liquid–liquid microextraction–two dimensional gas chromatography–time-of-flight mass spectrometry
PublicationPolycyclic aromatic hydrocarbons (PAHs) are contaminants frequently found in environmental waters. Owing to their toxic effects, it is important to develop analytical methodologies that allow their fast and reliable determination. Dispersive liquid–liquid microextraction (DLLME) allows a quick extraction of analytes with little organic solvent consumption. The best results regarding sample preparation are obtained when 40 mL of...
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Proton transfer and hydrogen bonds in supramolecular, self-assembled structures of imidazolium silanethiolates. X-ray, spectroscopic and theoretical studies
PublicationThe reaction of 1-methylimidazole, 2-ethyl-4-methylimidazole and 2-ethylimidazole with tris(2,6- diisopropylphenoxy)silanethiol (TDST) leads to the formation of three new salts, which have been characterized by elemental analyses, thermogravimetric analyses, FTIR spectroscopy, and their structures were determined by single-crystal X-ray diffraction. Structural analyses indicate that in all three compounds a proton transfer has...
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SURFACTANTS IN KLODNICA RIVER (KATOWICE, POLAND). PART II. QUATERNARY AMMONIUM COMPOUNDS
PublicationThe paper presents methods of determination of analytes of the cation group (alkyl benzyl dimethyl ammonium (BDDA-C12-C16), alkyl trimethyl ammonium (TMA), hexadecyl piridinium (HP)) in surface water and bottom sediment samples. In the sample preparation phase the solid phase extraction (SPE) or accelerated solvent extraction/ultrasound assisted extraction (ASE/UAE)-SPE technique was used and in the identification phase and quantitative...
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COMPARISON OF SOFTWARE AND HARDWARE REALIZATION OF AES CRYPTOGRAPHIC ALGORITHM
PublicationIn this paper hardware and software realization of direct and inverse AES cryptographic algorithm is presented. Both implementations were made using the Virtex-II FPGA and were practically tested. As the criteria of comparison, the resource utilization, achieved performance and power dissipation were chosen. Hardware realization increases throughput of conversion about 190 times over software implementation and decreases the energy...
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Przekształtnik do generatora wiatrowego włączanego do sieci jednofazowej
PublicationPopyt na energię ze źródeł odnawialnych prowadzi do konieczności opracowywania układów przekształtnikowych spełniających rzadko spotykane wymagania. Regulacje prawne oraz wymagania techniczne doprowadziły do opracowania generatora wiatrowego o mocy 11 kW dołączanego do jednofazowej sieci prądu przemiennego. Optymalizując koszty zaprojektowano przekształtnik z małym zasobnikiem energii zapewniającym minimalizację pojemności głównego...
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Rozpoznawanie obiektów przez głębokie sieci neuronowe
PublicationW referacie zaprezentowane zostaną wyniki badań nad rozpoznawaniem obiektów w różnych warunkach za pomocą głębokich sieci neuronowych. Przeanalizowano działanie dwóch struktur – ResNet50 oraz VGG19. Systemy rozpoznawania obrazu wytrenowano oraz przetestowano na reprezentatywnej, bazie zawierającej 25 tys. zdjęć psów oraz kotów, która znacznie upraszcza analizowanie działania systemów ze względu na łatwość interpretacji zdjęć przez...
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Persistent organic pollutants (POPs) as an indicator of surface water quality in the vicinity of the Polish Polar Station, Horsund
PublicationSurface waters were collected in the vicinity of the Polish Polar Station in Hornsund (Svalbard) to determine their concentration of various persistent organic pollutants (POPs), such as polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). In addition, parameters such as pH, SEC and TOC were measured. In total, 15 samples of lake water from and 15 samples of stream water were analysed. The sampling took...
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A convergence result for mountain pass periodic solutions of perturbed Hamiltonian systems
PublicationIn this work, we study second-order Hamiltonian systems under small perturbations. We assume that the main term of the system has a mountain pass structure, but do not suppose any condition on the perturbation. We prove the existence of a periodic solution. Moreover, we show that periodic solutions of perturbed systems converge to periodic solutions of the unperturbed systems if the perturbation tends to zero. The assumption on...
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Szerokopasmowy szyk antenowy wykorzystujący radiatory o brzegu fraktalnym
PublicationW pracy przedstawiono koncepcje szyku antenowego zbudowanego w technologii mikropaskowej, w oparciu o promienniki szczelinowe ze zmodyfikowanym kształtem brzegu. Modyfikacje brzegów szczeliny przeprowadzono wykorzystując krzywe fraktalne. Omówiono metodykę projektowania czteroelementowego szyku antenowego, którego radiatory posiadają krawędzie o kształcie fragmentu krzywej von Kocha (druga iteracja). Zaproponowano obwód zasilający...
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Quality Evaluation of Novel DTD Algorithm Based on Audio Watermarking
PublicationEcho cancellers typically employ a doubletalk detection (DTD) algorithm in order to keep the adaptive filter from diverging in the presence of near-end speech signal or other disruptive sounds in the microphone signal. A novel doubletalk detection algorithm based on techniques similar to those used for audio signal watermarking was introduced by the authors. The application of the described DTD algorithm within acoustic echo cancellation...
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Quantum-correlation breaking channels, broadcasting scenarios, and finite Markov chains
PublicationOne of the classical results concerning quantum channels is the characterization of entanglementbreakingchannels [M. Horodecki et al., Rev. Math. Phys 15, 629 (2003)]. We address the questionwhether there exists a similar characterization on the level of quantum correlations which may gobeyond entanglement. The answer is fully affirmative in the case of breaking quantum correlationsdown to the, so called, QC (Quantum-Classical)...
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Szybkie uziemniki do ograniczania skutków zwarć łukowych w okrętowych rozdzielnicach SN
PublicationW artykule scharakteryzowano moc i napięcie łuku, jak również przedstawiono model termodynamiczny służący do obliczania ciśnienia i temperatury gazów w otoczeniu łuku zwarciowego. Przedstawiono przykładowy układ elektrowni okrętowej i zasilania najważniejszych odbiorników na statku do przewozu gazu ziemnego w stanie ciekłym. Na podstawie parametrów prądnic i silników odbiorników zasilanych z rozdzielnicy głównej obliczono prądy...
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Metody doboru miejsc zainstalowania zasobników energii w sieciach elektroenergetycznych niskiego napięcia
PublicationW związku z rosnącą liczbą źródeł odnawialnych przyłączanych do sieci niskiego napięcia (nn) jakość energii elektrycznej w tej sieci ulega pogorszeniu. Jedną z metod jej poprawiania jest instalowanie zasobników energii, tj. baterii akumulatorów, superkondensatorów czy kół zamachowych. Zasobniki energii są w stanie złagodzić dobową zmienność obciążenia, skompensować moc bierną i wyższe harmoniczne oraz zmniejszyć asymetrię obciążenia...
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Effect of some organic solvent - water mixtures composion on precipitated calcium carbonate in carbonation process
PublicationPrecipitated calcium carbonate particles were obtained during carbonation of calcium hydroxide slurry with carbon dioxide. Aqueous solutions of isopropyl alcohol, n-butanol and glycerol were used as solvents. Concentration of organic additives in the reactive mixture was from 0 to 20 % (vol.). Precipitation process were performed in a stirred tank reactor equipped with gas distributor. Multimodal courses of particles size distribution...
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Wirtualny analizator stanów logicznych na bazie układu typu "System on a Chip"
PublicationW dobie dominacji układów cyfrowych, jednym z ważniejszych narzędzi uruchomieniowych jest analizator stanów logicznych (ASL). Komercyjne przyrządy nie są tanie, choć ich możliwości diagnostyczne uzasadniają cenę. W artykule przedstawiono ASL w konwencji przyrządu wirtualnego połączonego z PC poprzez interfejs USB, co obniża koszt urządzenia bez znaczącego pogorszenia jego możliwości. Wykorzystano układ typu SoC "System on a Chip"...
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Vibration surveillance of dynamic systems and production processes
PublicationPraca dotyczy poszukiwania sposobów minimalizacji poziomu drgań podczas pracy maszyn i urządzeń wykonujących określone procesy robocze. Do modelowania dyskretnego wykorzystano metodę elementów skończonych. Rozważano dynamikę niestacjonarnego dyskretnego układu sterowanego, którego zachowanie opisano we współrzędnych uogólnionych, jak również - układu hybrydowego. Ten ostatni uzyskano dzięki wyodrębnieniu z całości podukładu stacjonarnego,...
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Correlation between chemical composition and the presence of selected groups of bacteria in freshwater samples collected from Isfjorden and Billefjorde
PublicationThe average concentrations of pollutants in the arctic water, snow and the atmosphere are much lower than those observed in the temperate climate. Specific conditions occurring in the polar regions have apotential to accumulate the pollutants transported from other parts of the world. In this study, attempts were made to find a correlation between selected chemical components and the bacterial population. The analysis involved...
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Buckling Analysis of a Micro Composite Plate with Nano Coating Based on the Modified Couple Stress Theory
PublicationThe present study investigates the buckling of a thick sandwich plate under the biaxial non-uniform compression using the modified couple stress theory with various boundary conditions. For this purpose, the top and bottom faces are orthotropic graphene sheets and for the central core the isotropic soft materials are investigated. The simplified first order shear deformation theory (S-FSDT) is employed and the governing differential...
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Differential Quadrature Method for Dynamic Buckling of Graphene Sheet Coupled by a Viscoelastic Medium Using Neperian Frequency Based on Nonlocal Elasticity Theory
PublicationIn the present study, the dynamic buckling of the graphene sheet coupled by a viscoelastic matrix was studied. In light of the simplicity of Eringen's non-local continuum theory to considering the nanoscale influences, this theory was employed. Equations of motion and boundary conditions were obtained using Mindlin plate theory by taking nonlinear strains of von Kármán and Hamilton's principle into account. On the other hand, a...
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Projektowanie filtrów pasywnych wyższych harmonicznych
PublicationW artykule przedstawiono metodę projektowania grupy filtrów prostych, których charakterystyka częstotliwościowa jest dobrana w sposób optymalny, z uwzględnieniem wpływu pozostałych filtrów. Sumaryczna moc bierna pojemnościowa filtrów dla pierwszej harmonicznej ma wynosić 10kVAr. Celem grupy filtrów jest:• eliminacja wyższych harmonicznych z sieci zasilającej, których źródłem jest układ TCR, • kompensacja mocy biernej generowanej...