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Search results for: COMPOSITE STRUCTURE FEM ANALYSIS
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CeIr3: superconductivity in a phase based on tetragonally close packed clusters
PublicationWe present the crystallographic analysis, superconducting and spectroscopic characterization, and theoretical modeling of CeIr3. Lattice parameters a = 5.2945(1) Å and c = 26.219(1) Å are found for the R-3m symmetry crystal structure, which are close to the literature values. CeIr3 is a moderate type-II superconductor (κ GL = 17, λ e–p = 0.65) below 2.5 K. Ce ions exhibit a strongly intermediate valence character as evidenced by...
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Biologically active compounds based on the carbazole scaffold - synthetic and mechanistic aspects
PublicationDoctoral dissertation is divided into three main parts: introduction, results and discussion and experimental. The introduction is divided into four main parts which describe: 5-hydroxytryptamine receptors, the most popular antidepressants, new compounds based on the carbazole structure with affinity for serotonin receptors, telomeres and telomerase with their functions, telomerase inhibition strategies, carbazoles approved in...
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Efficient analysis of structures with rotatable elements using model order reduction
PublicationThis paper presents a novel full-wave technique which allows for a fast 3D finite element analysis of waveguide structures containing rotatable tuning elements of arbitrary shapes. Rotation of these elements changes the resonant frequencies of the structure, which can be used in the tuning process to obtain the S-characteristics desired for the device. For fast commutations of the response as the tuning elements are rotated, the...
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Mathematical modelling of the overhead contact line for the purpose of diagnostics of pantographs
PublicationThe overhead contact line (OCL) is the most effective way for supplying railway electric vehicles. The increase of the speed of the vehicles increases power consumption and requires ensuring proper cooperation of pantographs with OCL. The paper describes the novel mathematical model of the OCL system and the simulation results. The primary objective is a more accurate analysis to increase the reliability of the evaluation of monitoring...
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The impact of material degradation on the resistance and reliability of truss structures
PublicationThe paper analyses limit load-carrying capacity and buckling load of truss towers used to support high voltage power lines. The analysed typical structure was subjected to characteristic loads and their combinations. The results were applied to assess structural resistance with regard to steel corrosion in the long-term operation. The extent of structural deterioration was assessed due to Young's modulus decrement in the course...
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On Design Optimization of Miniaturized Microscrip Dual-Band Rat-Race Coupler with Enhanced Bandwidth
PublicationIn the paper, a novel topology of a miniaturized wideband dual-band rat-race coupler has been presented. Small size of the circuit has been obtained by meandering transmission lines of the conventional circuit. At the same time, the number of independent geometry parameters has been increased in order to secure sufficient circuit flexibility in the context of its design optimization for dual-band operation. Optimum dimensions of...
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Spectroscopic and cytotoxic characteristics of (p-cymene)Ru(II) complexes with bidentate coumarins and density functional theory comparison with selected Pd(II) complexes
PublicationThis paper presents the synthesis of two new (p-cymene)-ruthenium(II) complexes with the bidentate coumarin ligands. Both complexes were characterized by FTIR spectroscopy, 1H NMR, 13C NMR, MS, elemental analysis and DFT calculations. The X-ray structure of complex 3a was also solved. The cytotoxic properties of both complexes were examined on human leukemia NALM-6 and HL-60 cells and melanoma WM-115 cells. The complexes possess...
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Binuclear Co(II), Zn(II) and Cd(II) tri-tert-butoxysilanethiolates. Synthesis, crystal structure and spectroscopic studies.
PublicationA series of Co(II), Zn(II) and Cd(II) complexes have been synthesized in reaction of respective metal tri-tert-butoxysilanethiolates with pyrazine 1 and 2 and 1,2-bis(2-pyridyl)ethylene 3–5. All compounds have been characterized by single-crystal X-ray structure determination, elemental analysis, FT-IR and thermogravimetry. Obtained complexes are bimetallic with the formula of [M{SSi(OtBu)3}2(μ-L)]2 and metal ions bridged by N,N′-spacer....
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Reliability model of slide bearings with particular attention given to lubricating oil
PublicationThe paper presents the slide bearing with circulating lubrication as a system of series three-element structure, where lubricating oil is the weakest link. In accordance with the Pierce statement that ''strength of chain is the strength of its weakest link'', a bearing reliability model has been developed. It allows to use the lubricating oil to evaluate the probability of correct working of the whole slide bearing, i.e. the reliability....
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Timber Frame Houses with Different Insulation Materials - Seismic Analysis
PublicationThe aim of this article is to present results of a dynamic numerical analysis focused on the response of two timber frame building structures exposed to seismic excitations. The first structure was insulated with mineral wool, while the second one with polyurethane foam. Specifications and technology involved in the models' construction are based on the previously conducted experimental study, upon which numerical structural models...
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A spectroscopic study of the cis/trans-isomers of penta-2,4-dienoic acid attached to gold nanoclusters
PublicationIn this theoretical work, we present a spectroscopic analysis of the cis/trans-isomers of a molecular switch, penta-2,4-dienoic acid, attached to gold clusters of different size (1, 2 and 20 gold atoms). We have simulated 4 different spectroscopic techniques: Infrared spectroscopy, normal Raman scattering, absorption spectra and resonance Raman scattering. We discuss how the position and the conformation of the molecule determine...
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Fabrication of ILs-Assisted AgTaO3 Nanoparticles for the Water Splitting Reaction: The Effect of ILs on Morphology and Photoactivity
PublicationThe design of an active, stable and ecient photocatalyst that is able to be used for hydrogen production is of great interest nowadays. Therefore, four methods of AgTaO3 perovskite synthesis, such as hydrothermal, solvothermal, sol-gel and solid state reactions, were proposed in this study to identify the one with the highest hydrogen generation eciency by the water splitting reaction. The comprehensive results clearly show that...
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Modyfikacja kompozytów elastomerowych NR za pomocą ligniny i glicerolizatu
PublicationPrzedmiotem opisanych w niniejszym artykule badań są wulkanizaty kauczuku naturalnego. Celem pracy było zbadanie wpływu ligniny oraz glicerolizatu na wybrane właściwości kompozytów zawierających kauczuk naturalny. Strukturę chemiczną przygotowanych materiałów potwierdzono, wykorzystując analizę spektroskopową w podczerwieni (FTIR). Zbadano również właściwości mechaniczne przy statycznym rozciąganiu, twardość, ścieralność oraz odbojność...
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Instalacje fotowoltaiczne w budownictwie wielorodzinnym
PublicationArtykuł opisuje wpływ instalacji fotowoltaicznych na bezpieczeństwo eksploatacji budynków wielorodzinnych. W oparciu o projekty rzeczywistych obiektów przeprowadzono analizę zwiększenia ryzyka strat odgromowych, zmiany obciążenia konstrukcji dachu i wzrostu zagrożenia pożarowego na skutek montażu systemu fotowoltaicznego. Przeprowadzone obliczenia wskazują na konieczność kompleksowego podejścia do projektowania instalacji fotowoltaicznych....
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Assessment of the factors influencing on the formation of energy-oriented modes of electric power consumption by water-drainage installations of the mines
PublicationPurpose. Performing the analysis to determine energy-efficient modes and assess the characteristics of the main indicators of electric power consumption by mine water-drainage installations based on the developed research mathematical model. Methods. To achieve the purpose set, a methodology is used to develop the multiple multifactor correlation-regression modeling with respect to the modes of electric power consumption by electrical...
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THE METHOD OF ANALYSIS OF DAMAGE REINFORCED CONCRETE BEAMS USING TERRESTRIAL LASER SCANNING
PublicationThe authors present an analysis of the possibility to assess deformations and mode of failure of R-C beams using terrestrial laser scanning. As part of experiments carried out at the Regional Laboratory of Construction (at Gdansk University of Technology), reinforced concrete beams were subjected to destruction by bending and by shear. The process of press impact on the reinforced concrete beam was recorded using terrestrial laser...
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Poprawa jakości klasyfikacji głębokich sieci neuronowych poprzez optymalizację ich struktury i dwuetapowy proces uczenia
PublicationW pracy doktorskiej podjęto problem realizacji algorytmów głębokiego uczenia w warunkach deficytu danych uczących. Głównym celem było opracowanie podejścia optymalizującego strukturę sieci neuronowej oraz zastosowanie uczeniu dwuetapowym, w celu uzyskania mniejszych struktur, zachowując przy tym dokładności. Proponowane rozwiązania poddano testom na zadaniu klasyfikacji znamion skórnych na znamiona złośliwe i łagodne. W pierwszym...
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Analiza temperatury ekwiwalentnej do projektowania nawierzchni asfaltowych w Polsce z wykorzystaniem metody AASHTO 2004
PublicationW artykule przedstawiono analizę temperatury ekwiwalentnej obliczanej w oparciu o kryterium spękań zmęczeniowych warstw asfaltowych z metody AASHTO 2004 oraz kryterium deformacji strukturalnych Instytutu Asfaltowego. Do obliczeń przyjęto konstrukcję nawierzchni KR5 oraz wykorzystano dane temperaturowe z 50 stacji meteorologicznych z okresu 30 lat od roku 1989 do roku 2019 włącznie udostępnione przez Instytut Meteorologii i Gospodarki...
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APPLICATION OF CHEMOMETRIC ANALYSIS TO THE STUDY OF SNOW AT THE SUDETY MOUNTAINS, POLAND
PublicationSnow samples were collected during winter 2011/2012 in three posts in the Western Sudety Mountains (Poland) in 3 consecutive phases of snow cover development, i.e. stabilisation (Feb 1st), growth (Mar 15th) and its ablation (Mar 27th). To maintain a fixed number of samples, each snow profile has been divided into six layers, but hydrochemical indications were made for each 10 cm section of core. The complete data set was subjected...
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Ground tire rubber thermo-mechanically devulcanized in the presence of waste engine oil as asphalt modifier
PublicationCross-linked elastomers network is main limitation for industrial usage of ground tire rubber (GTR) as asphalts’ and road pavements modifier. GTR was thermo-mechanically devulcanized via extrusion in the presence of waste engine oil (WEO) at temperature ranges from 150 to 280 °C. Combined impact of WEO content and extruder barrel temperature on the change of cross-linked structure of degraded GTR (DTGR) was investigated through...
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Structural, mechanical and thermal behavior assessments of PCL/PHB blends reactively compatibilized with organic peroxides
PublicationThe efficiency of two commercially available organic peroxides, dicumyl peroxide (DCP) and di-(2-tert-butyl-peroxyisopropyl)-benzene (BIB), during reactive processing of poly (ε-caprolactone)/poly (3-hydroxybutyrate) (PCL/PHB) blends was investigated. The changes in chemical structure of PCL/PHB blends, as a function of organic peroxide type (DCP/BIB) and content (in range: 0–1.0 parts by weight - pbw), were characterized by Fourier...
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Design and Experimental Validation of a Metamaterial-Based Sensor for Microwave Imaging in Breast, Lung, and Brain Cancer Detection
PublicationThis study proposes an innovative geometry of a microstrip sensor for high-resolution microwave imaging (MWI). The main intended application of the sensor is early detection of breast, lung, and brain cancer. The proposed design consists of a microstrip patch antenna fed by a coplanar waveguide with a metamaterial layer-based lens implemented on the back side, and an artificial magnetic conductor (AMC) realized on as a separate...
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Bovine Serum Albumin – Hydroxyapatite Nanoflowers as Potential Local Drug Delivery System of Ciprofloxacin
PublicationIntroduction: Hybrid nanoflowers are structures consisting of organic (enzymes, proteins, nucleic acids) and inorganic components (mostly metal phosphates) with a flower-like hierarchical structure. Novel hybrid nanoflowers based on bovine serum albumin (BSA) and hydroxyapatite (HA) were obtained and characterized. Study on BSA-HA nanoflowers as potential drug delivery system is reported for the first time. Methods: Embedding ciprofloxacin...
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Properties of nano-Fe3O4 incorporated epoxy coatings from Cure Index perspective
PublicationThe mission of an advanced epoxy-based nanocomposite coating is to provide a given substrate with protection against an unwelcome guest; e.g. corrosive molecules/media, environmental stress, flame, thermal degradation or microorganisms. In such systems, the degree to which superior properties can be guaranteed depends on the state of network formation in the epoxy in the presence of nanoparticles. For low-filled epoxy nanocomposite coatings,...
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Effect of Individual Components of Lignocellulosic Biomass on Methane Production and Methanogen Community Structure
PublicationOne of the major factors that influences the economic feasibility of biogas production is the availability of digestible feedstocks. There is little research on the influence of the chemical composition of biomass on biogas synthesis, especially with regard to the content of lignocellulosic materials. Therefore, the aim of this study was to estimate how differences in the content of cellulose and lignin in lignocellulosic biomass...
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Superconducting SrSnP with Strong Sn–P Antibonding Interaction: Is the Sn Atom Single or Mixed Valent?
PublicationThe large single crystals of SrSnP were prepared using Sn self-flux method. The superconductivity in the tetragonal SrSnP is observed with the critical temperature of ∼2.3 K. The results of a crystallographic analysis, superconducting characterization, and theoretical assessment of tetragonal SrSnP are presented. The SrSnP crystallizes in the CaGaN structure type with space group P4/nmm (S.G. 129, Pearson symbol tP6) according...
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Innovative method of localization airplanes in VCS (VCS-MLAT) distributed system
PublicationThe article presents the concept and the structure of the localization module. The prototype module is the part of the VCS (VCS-MLAT) localization distributed system. The device receives the audio signal transmitted in airplanes band (118 MHz – 136 MHz). Received data with the timestamps are send to the main server. The data from multiple devices estimates the localization of the airplane. The main aim of the project is the analysis...
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Structural Properties and Water Uptake of SrTi1−xFexO3−x/2−δ
PublicationIn this work, Fe-doped strontium titanate SrTi1−xFexO3−x/2−δ, for x = 0–1 (STFx), has been fabricated and studied. The structure and microstructure analysis showed that the Fe amount in SrTi1−xFexO3−x/2−δ has a great influence on the lattice parameter and microstructure, including the porosity and grain size. Oxygen nonstoichiometry studies performed by thermogravimetry at different atmospheres showed that the Fe-rich compositions...
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Rotational Molding of Linear Low-Density Polyethylene Composites Filled with Wheat Bran
PublicationApplication of lignocellulosic fillers in the manufacturing of wood polymer composites (WPCs) is a very popular trend of research, however it is still rarely observed in the case of rotational molding. The present study aimed to analyze the impact of wheat bran content (from 2.5 wt.% to 20 wt.%) on the performance of rotationally-molded composites based on a linear low-density polyethylene (LLDPE) matrix. Microscopic structure...
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Machine learning-based prediction of seismic limit-state capacity of steel moment-resisting frames considering soil-structure interaction
PublicationRegarding the unpredictable and complex nature of seismic excitations, there is a need for vulnerability assessment of newly constructed or existing structures. Predicting the seismic limit-state capacity of steel Moment-Resisting Frames (MRFs) can help designers to have a preliminary estimation and improve their views about the seismic performance of the designed structure. This study improved data-driven decision techniques in...
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Generalized Pareto ranking bisection for computationally feasible multi-objective antenna optimization
PublicationMulti-objective optimization (MO) allows for obtaining comprehensive information about possible design trade-offs of a given antenna structure. Yet, executing MO using the most popular class of techniques, population-based metaheuristics, may be computationally prohibitive when full-wave EM analysis is utilized for antenna evaluation. In this work, a low-cost and fully deterministic MO methodology is introduced. The proposed generalized...
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The Spatial Structure of Suburban Zones in Selected Entrepreneurship Nets of the Tricity Metropolitan Area
PublicationThe chapter describes spatial structures and forms of Polish suburban zones shown on the example of two selected towns in the Trojmiasto Metropolitan Area (TMA). The description of the spatial characteristics in the urban sprawl, with focus on the entrepreneurships nests is illustrated by the choice of typological features, such as: form, land use, density. Suburbanisation is described to be global, however one can observe individual...
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Optimization of carbamazepine photodegradation on defective TiO2-based magnetic photocatalyst
PublicationIn this work, carbamazepine (CBZ) degradation over defective Fe3O4@SiO2/d-TiO2/Pt photocatalyst was studied. Within the titania structure, Ti vacancies and Pt nanoparticles were introduced to enhance the photocatalyst’s light absorption and influence charge carriers’ mobility. For the carbamazepine degradation, process parameters, e.g., temperature, flux intensity, photocatalyst loading, aeration, pH, and addition of H2O2, were optimized...
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Structure-based design and evaluation of novel N-phenyl-1H-indol-2-amine derivatives for fat mass and obesity-associated (FTO) protein inhibition
PublicationFat mass and obesity-associated (FTO) protein contributes to non-syndromic human obesity which refers to excessive fat accumulation in human body and results in health risk. FTO protein has become a promising target for anti-obesity medicines as there is an immense need for the rational design of potent inhibitors to treat obesity. In our study, a new scaffold N-phenyl-1H-indol-2-amine was selected as a base for FTO protein inhibitors...
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Novel single-stranded DNA-binding protein from psyvhrophilic bacterium Psychrobacter arcticus
PublicationTo study the biochemical properties of SSB from Psychrobacter arcticus (ParSSB), we have cloned the ssb genes obtained by PCR and have developed Escherichia coli overexpression systems. The gene consists of an open reading frame of 642 nucleotides encoding SSB protein of 213 amino acids with a calculated molecular mass of 22.8 kDa. The amino-acid sequence of ParSSB exhibits 49% identity and 57% similarity to Escherichia coli SSB....
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Refurbishment of a historical building - design issues
PublicationOver a 10-year modernization of the main building of Gdansk University of Technology is coming to the end. The ever increasing number of students requires not only the development of the campus with new facility buildings, also the existing buildings are subject to adaptation and modernization. In addition to high-impact solutions, as restoring the former glory of the building (reconstruction of the clock tower), or introducing...
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Chemical Structure and Thermal Properties versus Accelerated Aging of Bio-Based Poly(ether-urethanes) with Modified Hard Segments
PublicationAging of polymers is a natural process that occurs during their usage and storage. Predicting the lifetime of polymers is a crucial aspect that should be considered at the design stage. In this paper, a series of bio-based thermoplastic poly(ether-urethane) elastomers (bio-TPUs) with modified hard segments were synthesized and investigated to understand the structural and property changes triggered by accelerated aging. The bio-TPUs...
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Do Phenyl Substituents Affect the Properties of Azobenzocrown Derivatives?
PublicationNew products of photo- and thermal rearrangements of 19-membered azoxybenzocrown with phenyl substituents in benzene rings in the para positions to oligooxyethylene fragments are characterized. The yields of photochemical transformations depend on the solvent. Para-hydroxyazocrown is formed with yields over 50% in propan-2-ol. Ortho-hydroxyazobenzocrown is obtained with yields up to 70% in toluene/acetic acid mixture. Macrocyclic...
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Effect of osmolytes of different type on DNA behavior in aqueous solution. Experimental and theoretical studies
PublicationOsmolytes, the small organic molecules accumulated in cells under environmental stress, can modulate the stability of biopolymers such as proteins and DNA. In spite of many years of research, there is no established molecular mechanism of the influence of osmolytes on DNA structure. Here, we used two model osmolytes that denature (urea) or stabilize (trimethylglycine, TMG) proteins to study their effect on DNA in aqueous solutions...
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Studies on novel BiyXz-TiO2/SrTiO3 composites: Surface properties and visible light-driven photoactivity
PublicationA series of novel BiyXz-TiO2/SrTiO3 composites were prepared by multistep synthesis route. The asprepared photocatalysts were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), diffuse reflectance spectroscopy (DRS), Fourier transform infrared (FT-IR), Raman spectra and BET analysis. The photocatalytic activity test was performed in aqueous solution of phenol under...
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In-tube extraction for the determination of the main volatile compounds in Physalis peruviana L
PublicationAn analytical procedure based on in-tube extraction followed by gas chromatography with mass spectrometry has been developed for the analysis of 24 main volatile components in cape gooseberry (Physalis peruviana L.) samples. According to their chemical structure, the compounds were organized into different groups: one hydrocarbon, one aldehyde, four alcohols, four esters, and 14 monoterpenes. By single-factor experiments, incubation...
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Pawlak's flow graph extensions for video surveillance systems
PublicationThe idea of the Pawlak's flow graphs is applicable to many problems in various fields related to decision algorithms or data mining. The flow graphs can be used also in the video surveillance systems. Especially in distributed multi-camera systems which are problematic to be handled by human operators because of their limited perception. In such systems automated video analysis needs to be implemented. Important part of this analysis...
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Visual method for detecting critical damage in railway contact strips
PublicationEnsuring an uninterrupted supply of power in the electric traction is vital for the safety of this important transport system. For this purpose, monitoring and diagnostics of the technical condition of the vehicle's power supply elements are becoming increasingly common. This paper presents a new visual method for detecting contact strip damage, based on measurement and analysis of the movement of the overhead contact line (OCL)...
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Wrażliwość probabilistyczna stanów granicznych konstrukcji - metoda Monte Carlo
PublicationPraca ukazuje zastosowanie metody symulacyjnej Monte Carlo w analizie losowej konstrukcji inżynierskich. Systematyka metod losowych obejmuje ich trzy poziomy, z zaznaczeniem poziomu trzeciego, o dowolnych typach zmiennych losowych – zmiennych podstawowych problemu. Ukazano przykład modelowana losowego obciążenia wiatrem na podstawie 10-letnich pomiarów prędkości wiatru, wykazując zgodność zbioru danych z rozkładem ekstremów Gumbela....
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Fermentative Conversion of Two-Step Pre-Treated Lignocellulosic Biomass to Hydrogen
PublicationFermentative hydrogen production via dark fermentation with the application of lignocellulosic biomass requires a multistep pre-treatment procedure, due to the complexed structure of the raw material. Hence, the comparison of the hydrogen productivity potential of different lignocellulosic materials (LCMs) in relation to the lignocellulosic biomass composition is often considered as an interesting field of research. In this study,...
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Energy efficiency of electric multiple units in suburban operation
PublicationThis thesis presents approach to analysis of energy efficiency of a suburban rail network, using novel models developed on the Matlab/Simulink basis. Necessary features and requirements for such models were determined thru in-depth review of the source literature in all applicable fields: electrified transportation systems, electric multiple units construction, vehicle drivetrains and finally, existing simulation methods. Existing...
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Structural analysis as a supporting method for the research of the medieval brick architecture
PublicationChronology of brick historical buildings might be established much more precisely than the chronology of stone ones due to the architectural and metrical analysis of bricks, mortars and brickworks. Comparison of historical sources allows to reconstruct the previous stages of constructing monuments. Causations between transformations and developments of monuments are usually interpreted as the results of artistic or ideological...
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The Application of Fluidic Sealing in Shrouded Gas Turbine Blades
PublicationThis paper presents a study conducted on a new gas turbine designed to limit leakage in the labyrinth seal. The slots in the fin are used to generate a bypass flow, which obstructs the flow in the gap above the fin. The method was tested numerically and experimentally beforehand using a simplified model without rotation or blade passages. In this paper, the validation of the method using a model of a turbine stage is shown. Reynolds-averaged...
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Peptide dendrimers as antifungal agents and carriers for potential antifungal agent—N3‐(4‐methoxyfumaroyl)‐(S)‐2,3‐ diaminopropanoic acid—synthesis and antimicrobial activity
PublicationA series of peptide dendrimers and their conjugates with antimicrobial agent FMDP (N3‐(4‐methoxyfumaroyl)‐(S)‐2,3‐diamino‐propanoic acid) were synthesized. The obtained compounds were tested for the antibacterial and antifungal activity. All novel dendrimers displayed much better activity against the tested strains than FMDP itself. Moreover, their conjugates with FMDP also exhibited antimicrobial activity. The most promising molecules...
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Sealing tax collection in Poland and the EU in the years 2008–2018
PublicationThe purpose of this study is to present issues related to sealing tax collection system in Poland and European Union countries as well as OECD members in 2008–2018. The article is divided into four parts, which include: introduction, origin of the problem, implemented solutions and conclusions. It presents the results of the conducted analysis including studies of the literature and empirical data (mainly from OECD, GUS—Polish...