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Representation of magnetic hysteresis in tape wound core using feedback Preisach model
PublikacjaThis paper presents a mathematical model for the hysteresis phenomenon in ferromagnetic tape wound core. The feedback scalar Preisach model of hysteresis is used to simulate magnetic behavior of the grain oriented silicon strip of ET114-27 type. Determination of B-H hysteretic curve is based on measurement of the initial magnetization curve and the main hysteresis loop. The Preisach distribution function (PDF) of ET114-27 material...
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MEMS Modeling in the Context of Inertial Navigation
PublikacjaUnderwater navigation is a research topic current undertaken in many areas of underwater research. The article presents an analysis resulting from MEMS modelling in the context of inertial navigation. The ideal approach was confronted with its limitations, but a non-linear approach, close to the real one, was also presented. Both models were compared in the context of inertial navigation. Random disturbances and their impact on linear...
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Application of Diversity Combining with RLS Adaptive Filtering in Data Transmission in a Hydroacoustic Channel
PublikacjaWhen transmitting data in a hydroacoustic channel under difficult propagation conditions, one of the problems is intersymbol interference (ISI) caused mainly by the effect of multipath propagation. This phenomenon leads to a decrease in transmission parameters, and sometimes completely prevents it. Therefore, we have made an attempt to use diversity combining with Recursive Least Squares (RLS) adaptive filtering to improve the...
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NUMERICAL SIMULATIONS OF GAP FLOW ABOVE ROTATING DISK
PublikacjaA rotating disk can be considered a basic configuration for the investigati ons of the impact of various conditions on the flow through the clearance between the s hrouded turbine blade and the casing. Numerical calculations using Fine/Turbo Numeca were conducted to examine the influence of the rotational velocity and the pressure differ ence across the disk on the flow conditions, especially the mass flow through the clearance....
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New Aspects of Virtual Sound Source Localization Research—Impact of Visual Angle and 3-D Video Content on Sound Perception
PublikacjaThe influence of image on virtual sound source localization, called the “image proximity effect” or the “ventriloquism effect”, is a well known phenomenon. This paper focuses on other aspects related to this effect, namely the impact of the visual angle of the presented object and 3D video content on sound perception. The research conducted confirmed that the visual angle of the presented object determines the image proximity effect...
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Model of heat transfer in the stagnation point of rapidly evaporating microjet
PublikacjaThe paper presents investigation into the single water microjet surface cooling producing evaporating film. Reported tests were conducted under steady state conditions. Experiments were conducted using the nozzle size of 70 and 100 mikrometer respectively. In the course of investigations obtained were experimental relations between heat flux and wall superheating. It was proved that the phenomenon is similar to that of pool boiling...
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Mechanism of the Reaction of Amines with 5-[(Aryl- or Alkylamino)hydroxymethylene]-2,2-dimethyl-1,3-dioxane-4,6-diones in the Presence of Chlorotrimethylsilane (Me3SiCl);
PublikacjaAddition of chlorotrimethylsilane (Me3SiCl) to the mixture of a carbamoyl‐substituted Meldrum's acid, i.e., a 5‐[(arylamino)hydroxymethylene]‐2,2‐dimethyl‐1,3‐dioxane‐4,6‐dione of type 1 and a secondary amine as nucleophile strongly accelerated the rate of their reaction. The reason for this phenomenon observed, during our previous research, remained, however, unclear. To elucidate the mechanism of this reaction, we assumed and...
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AN OVERVIEW OF HEAT TRANSFER ENHANCEMENT BASED UPON NANOPARTICLES INFLUENCED BY INDUCED MAGNETIC FIELD WITH SLIP CONDITION VIA FINITE ELEMENT STRATEGY
PublikacjaThe mathematical model of heat generation and dissipation during thermal energy transmission employing nanoparticles in a Newtonian medium is investigated. Dimensionless boundary layer equations with correlations for titanium dioxide, copper oxide, and aluminium oxide are solved by the finite element method. Parameters are varied to analyze their impact on the flow fields. Various numerical experiments are performed consecutively...
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Computational Fluid Dynamics Simulation of Gas–Liquid Multiphase Flow in T-junction for CO2 Separation
PublikacjaThe article presents the results of a computational fluid dynamics (CFD) analysis of gas-liquid multiphase flow. The simulation was conducted using CFD code and the Euler–Euler approach. The presented study relates to the non–reactive, steady-state, turbulent flow of water and carbon dioxide mixture in a 3D pipe. Separation phenomenon between phases is observed. The solution was obtained using a mixture model. Different values...
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A Computational Analysis of the Aerodynamic and Aeromechanical Behavior of a Thermo-Well for Steam Temperature Measurement in a Steam Turbine
PublikacjaThe goal of the paper is twofold: firstly, it presents computational fluid dynamics analysis for finding maximum unsteady flow forces (and their frequencies) acting on a thermo-well for measuring steam temperature in a steam turbine control stage and secondly, it presents computational solid dynamics analysis of possibility of entry into resonance of the thermowell structure. There have been analyzed two cases of flow with changing...
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Stability analysis of a dike constructed of anthropogenic materials
PublikacjaNumerical analyses of stability are presented for a hypothetical dikes constructed of dredged materials and bottom ash, in varying proportions. The paper is related to the international research project DredgDikes, which focused on the use of anthropogenic materials in dikes construction and flood protection. The aim of this project was to investigate the possibility of using anthropogenic materials from rivers and sea dredging...
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Wskaźnik przedsiębiorczości w jednostkach terytorialnych Polski – zróżnicowanie w czasie i przestrzeni
PublikacjaPrzedmiotem artykułu jest analiza zjawiska prowadzenia działalności gospodarczej przez osoby fizyczne, mierzonego poprzez wskaźnik liczby tych osób na 100 osób w wieku produkcyjnym. Wskaźnik ten nazywany jest nieraz wskaźnikiem przedsiębiorczości, mimo, że mierzy tylko jeden z jej przejawów. Badania prowadzono w układzie podregionów, powiatów i gmin (według ich rodzaju, z wyodrębnieniem miast w gminach miejsko-wiejskich). Celem...
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Synagogi dawnej Polski - ich teraźniejszość i przyszłość
PublikacjaTekst stanowi próbę ujęcia w szerszej perspektywie złożonego zjawiska zmiany formy użytkowania ocalałych obiektów kultu religijnego. Postępująca sekularyzacja współczesnych społeczeństw stanowi wyzwanie dla religijnych społeczności różnych wyznań, przynosząc również pytania dotyczące zmiany przeznaczenia pustoszejących świątyń. Biorąc pod uwagę społeczny kontekst zarysowany powyżej, ocalałe budynki synagog można uznać za odrębny,...
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Entrepreneurship in Virtual Economy: the Case of Currency One SA
PublikacjaPurpose: The scientific purpose of the study is an attempted synthesis of interpretation of “the virtual economy” and “the virtual environment” in the Polish and foreign literature on the subject. The cognitive purpose thereof is to offer an identification and a qualitative analysis of the factors that determine the development of e-entrepreneurship using an example of business practice. Methodology: The theoretical basis of the...
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Searching of the buried objects into the sea bottom by means of nonlinear acouctic methods
PublikacjaThe main goal of this paper is to introduce the methodology of preparing the area for investigations that will be carried out at the sea. As the first step there is recognition of the basic method both in the theory as well as experimental investigation. There were taken into account the nonlinear methods. These ones are very promising methods that have very interesting features, very convenient for examinations of the seabed structure....
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Potrzeby osób z niepełnosprawnością a budżet obywatelski. Wyniki ankiety opinii wśród społeczności warszawskiego Muranowa
PublikacjaThe participatory budget in Warsaw is a form of citizen involvement in city planning. The projects submitted in the budget concern, among other things, the physical transformation of space, organizing events integrating the community, and educational programs. Each of the above categories may determine the inclusion of people with disabilities in society. Social inclusion in the perspective of city change is an interesting and...
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Interaction Between Storm Water Conduit Flow and Overland Flow for Numerical Modelling of Urban Area Inundation
PublikacjaNowadays we can observe increasing frequency of inundations in cities. This makes accurate predicting of inundations more important than ever. Numerical modeling of this issue requires complex approach with simultaneous calculations of pipe flow and surface flow. In this paper, after a short review of known methods used for solving pipe and surface flow, we will try to answer the question if presented methods would be sufficiently...
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The methylome and transcriptome of fetal skin: implications for scarless healing
PublikacjaAim: Fetal skin is known to heal without scarring. In mice, the phenomenon is observed until the 16–17 day of gestation – the day of transition from scarless to normal healing. The study aims to identify key methylome and transcriptome changes following the transition. Materials & methods: Methylome and transcriptome profiles were analyzed in murine dorsal skin using microarray approach. Results & conclusion: The genes associated...
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Finite Element Method Applied in Electromagnetic NDTE: - A Review
PublikacjaThe paper contains an original comprehensive review of finite element analysis (FEA) applied by researchers to calibrate and improve existing and developing electromagnetic non-destructive testing and evaluation techniques, including but not limited to magnetic flux leakage (MFL), eddy current testing, electromagnetic-acoustic transducers (EMATs). Premium is put on the detection and modelling of magnetic field, as the vast majority...
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Roofing Materials as Pollution Emiters - Concentration Changes During Runoff
PublikacjaThe influence of roofing material on concentration of pollutants in roof runoff waters and changes of pollution concentration in time were investigated. In field studies four roofing material types were taken into consideration - ceramic tile, bituminous membrane, asbestos tile and zinc sheeting. Samples were collected since November 2007 to March 2008, anions, cations, metals, PAHs, pesticides and PCB were determined. The existence...
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Detection of sulfonamide resistance genes via in situ PCR-FISH
PublikacjaDue to the rising use of antibiotics and as a consequence of their concentration in the environment an increasing number of antibiotic resistant bacteria is observed. The phenomenon has a hazardous impact on human and animal life. Sulfamethoxazole is one of the sulfonamides commonly detected in surface waters and soil. The aim of the study was to detect sulfamethoxazole resistance genes in activated sludge biocenosis by use of...
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Voltage and Current Unbalance Reduction in Power Networks with Distributed Generation and Electric Vehicles
PublikacjaThe current development of prosumer microsources and the expected spread of electric vehicles may cause the appearance of significant current and voltage unbalance in low-voltage (LV) networks. This unbalance, which is an unfavorable phenomenon, may occur when using single-phase photovoltaic (PV) microsources and single-phase home chargers for electric vehicles. This paper presents a proposal for the symmetrization of the LV network...
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RESEARCH ON HYDRODYNAMIC PEEK JOURNAL BEARINGS LUBRICATED WITH WATER AND OIL
PublikacjaThe main purpose of the research was to determine the possibilities and experimentally test the benefits of replacing conventional oil lubrication with ecological water lubrication. Tests were carried out on a test rig for hydrodynamic radial bearings under conditions representative of the expected applications for the bearing in water turbines. Bearings made from the polymer material PEEK (polyether ether ketone) were tested under static...
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Exploring Stock Traders’ Cognitive Biases: Research Design and Simulator Framework
PublikacjaCognitive bias is a phenomenon that has been extensively studied in stock trading and many other fields. This paper presents a framework for a Mobile Stock Trading Simulator (MSTS) that facilitates automatic investment in stocks with minimal human influence, by investigating the behavioral patterns and cognitive errors of stock market investors. The paper aims to determine whether investors’ investment strategies can be improved...
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Changes in conditions of acoustic wave propagation in the Gdansk deep as an effect of climate changes in the Baltic Sea region
PublikacjaThe article presents the results from a research project investigating acoustic climate changes in the Gdansk Deep based on data extending from 1902 to 2019. This part of the southern Gotland Basin, is rarely discussed in the scientific literature. The speed of sound in the seawater is a function of temperature, salinity, and depth. In such shallow sea as Baltic Sea, the impact of depth is not substantial. The other two factors...
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Three-Dimensional Printing of Bone Models
PublikacjaThe trabecular bone occurs, for example, in the femoral heads. Understanding the phenomenon of bone tissue degeneration can be the basis for the possibility of looking for alternative methods of surgical treatment of bone loss. The paper presents the results of the trabecular bone model, which was produced in additive manufacturing method with fused filament fabrication technology. The verification of the mechanical behavior of...
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Measurements of the Hydraulic Fluids Compressibility
PublikacjaPerformance of the hydrostatic high-pressure drive systems is affected by the changes of working fluid’s volume. Presence of air bubbles in the fluid cause this problem to be even more serious. To study this phenomenon precise measurements of fluid’s bulk modulus are necessary. Differ-ent measurement methods are applied, but they are either limited to low pressure range or give inaccurate results. To solve the problem the new...
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Quantitative Storytelling in the Making of a Composite Indicator
PublikacjaThe reasons for and against composite indicators are briefly reviewed, as well as the available theories for their construction. After noting the strong normative dimension of these measures—which ultimately aim to ‘tell a story’, e.g. to promote the social discovery of a particular phenomenon, we inquire whether a less partisan use of a composite indicator can be proposed by allowing more latitude in the framing of its construction....
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How Chain Transfer Leads to a Uniform Polymer Particle Morphology and Prevents Reactor Fouling
PublikacjaABSTRACT: The effect of adding diethyl zinc as a chain transfer agent during the polymerization of propylene in heptane performed at 80 °C was studied. Although it was expected that the chain transfer would stop after precipitation of the polymer, the polymer molecular weight continued to increase throughout the whole of the polymerization. The presence of diethyl zinc had an additional effect that the polymerizations were devoid...
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Artificial intelligence and productivity: global evidence from AI patent and bibliometric data
PublikacjaIn this paper we analyse the relationship between technological innovation in the artificial intelligence (AI) domain and macroeconomic productivity. We embed recently released data on patents and publications related to AI in an augmented model of productivity growth, which we estimate for the OECD countries and compare to an extended sample including non-OECD countries. Our estimates provide evidence in favour of the modern productivity...
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The “autumn effect” in the gold market—does it contradict the Adaptive Market Hypothesis?
PublikacjaThe present study aims to verify the autumn effect in the gold market, first presented 10 years ago by Dirk Baur in the paper “The autumn effect of gold” and to investigate the calendar effects occurring for other precious metals. This empirical research is presented in a way to place the results obtained in the context of the Efficient Market Hypothesis (EMH) and the more current Adaptive Market Hypothesis (AMH). The study was...
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Meldrum’s acid assisted formation of tetrahydroquinolin‑2‑one derivatives a short synthetic pathway to the biologically useful scaffold
PublikacjaA new method for the preparation of tetrahydroquinolin-2-one derivatives is presented. This approach involves a two-step reaction between enaminones and acylating agents, immediately followed by electrophilic cyclization, all within a single synthesis procedure, eliminating the need to isolate intermediates. The entire process is facilitated by the use of acyl Meldrum’s acids which not only shortens the preparation time of the...
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Viscoplastic damage analysis of structures subjected to impact loading. Plate and shell structures. - Ł. Pyrzowski.
PublikacjaThe work presents the investigation in the response of plate-shell structures subjected to impact loading (gas mixture explosions). This phenomenon is studied in the context of its mechanical aspects, mainly the ductile fracture prediction. The work starts with the literature review and the description of theories, which are nowadays the most popular in the damage and failure modelling. After selecting the theoretical models and...
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Shape Memory Materials from Rubbers
PublikacjaSmart materials are much discussed in the current research scenario. The shape memory effect is one of the most fascinating occurrences in smart materials, both in terms of the phenomenon and its applications. Many metal alloys and polymers exhibit the shape memory effect (SME). Shape memory properties of elastomers, such as rubbers, polyurethanes, and other elastomers, are discussed in depth in this paper. The theory, factors...
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Voltage profiles improvement in a power network with PV energy sources – results of a voltage regulator implementation
PublikacjaThe constant increase in the number of photovoltaic (PV) energy sources in distribution networks is the cause of serious voltage problems. The networks built at least a dozen years ago are not provided for the installation of a large number of micro-sources. It happens that the previously properly functioning power networks are not able to provide to consumers power with the required parameters, after installing many PV sources....
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On forced vibrations of piezo-flexomagnetic nano-actuator beams
PublikacjaThe effect of excitation frequency on the piezomagnetic Euler-Bernoulli nanobeam taking the flexomagnetic material phenomenon into consideration is investigated in this chapter. The magnetization with strain gradients creates flexomagneticity. We couple simultaneously the piezomagnetic and flexomagnetic properties in an inverse magnetization. Resemble the flexoelectricity, the flexomagneticity is also size-dependent. So, it has...
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Genome-wide DNA methylation profiling of the regenerative MRL/MpJ mouse and two normal strains
PublikacjaAims We aimed to identify the pivotal differences in the DNA methylation profiles between the regeneration capable MRL/MpJ mouse and reference mouse strains. Materials and Methods Global DNA methylation profiling was performed in ear pinnae, bone marrow, spleen, liver, heart from uninjured adult females of the MRL/MpJ and C57BL/6J and BALB/c. Results and conclusion A number of differentially methylated regions distinguishing between...
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A study of a reduction of a micro- and nanometric bismuth oxide in hydrogen atmosphere
PublikacjaA reduction of bismuth oxide in hydrogen atmosphere was investigated. The reaction was performed with a material in various structural forms: powder: with micrometric grains, powder with nanometric grains and powder pressed into pellets. The process was performed in both isothermal and non-isothermal conditions. An activation energy of the reaction calculated with Friedman method was found to be about 85 kJ/mol for the reduction...
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Determination of the minimal critical rotational speeds of the circular saw blades with the quasi-twin resonant frequencies
PublikacjaTo determine the minimal critical rotational speeds of the circular saw blades is the fundamental aspect of obtaining the range of the rotational operating speeds, by which the circular saw blade can work with required stability. While for the circular saw blades with full-homogeneous bodies the determination of such rotational speeds is the relatively low level of difficulty function, whereas for circular saw blades with more...
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Consumerism and the Quality of Life
PublikacjaHigh level of consumption, driven by marketing activities, the pleasure and joy of possession and the accumulation of material goods are often associated with prosperity, sense of happiness and fulfilment in life. On a broader scale, economic indicators related to production and consumption are used to define the well-being and quality of life in societies. Unfortunately, the phenomenon of consumerism entails negative social and...
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Recycled Polyethylene terephthalate (PET) as Construction Material in Civil Engineering: A Review
PublikacjaIn general, the quantity of plastics of all types consumed annually all over the world has been growing in a phenomenal way. The manufacturing processes, service industries and municipal solid wastes (MSW) generate numerous waste plastic materials. The increasing awareness about the environment has tremendously contributed to the concerns related with disposal of the generated wastes. It is believed that the management of solid...
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The impact of initial and boundary conditions on severe weather event simulations using a high-resolution WRF model. Case study of the derecho event in Poland on 11 August 2017
PublikacjaPrecise simulations of severe weather events are a challenge in the era of changing climate. By performing simulations correctly and accurately, these phenomena can be studied and better understood. In this paper, we have verified how different initial and boundary conditions affect the quality of simulations performed using the Weather Research and Forecasting Model (WRF). For our analysis, we chose...
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Structural evaluation of percolating, self-healing polyurethane–polycaprolactone blends doped with metallic, ferromagnetic, and modified graphene fillers
PublikacjaComposites with differently shaped micro- and nanofillers show various, unique thermal, and physicochemical properties when mixed with carefully chosen polymer matrix. Selected composition holds strategic value in achieving desired properties that is biodegradability, thermoelectric conductivity, and shape memory for organic coating. The main aim of this work is to briefly examine structural changes after reaching percolation...
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Positive management of the university
PublikacjaPurpose: To demonstrate that contemporary universities may be improved by synthesis of strategic antinomies, i.e. seeking the possibility of combining opposite approaches to solving problems concerning university organization and management. Findings: That approach discounts the importance of building positive relationships between members of staff and undertaking activities intended to create a situation where the...
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Nonlinear secondary arc model use for evaluation of single pole auto-reclosing effectiveness
PublikacjaPurpose – The purpose of this paper is to discuss two evaluation methods of single pole autoreclosing process effectiveness in HV transmission lines. Secondary arc current and recovery voltage results obtained by load flow calculation are compared to the results obtained by the time domain simulations. Moreover, a nonlinear secondary arc implementation is presented. Design/methodology/approach – A computer simulation studies were...
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A quasi-2D small-signal MOSFET model - main results
PublikacjaDynamic 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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Novel approach to modeling spectral-domain optical coherence tomography with Monte Carlo method
PublikacjaNumerical modeling Optical Coherence Tomography (OCT) systems is needed for optical setup optimization, development of new signal processing methods and assessment of impact of different physical phenomena inside the sample on OCT signal. The Monte Carlo method has been often used for modeling Optical Coherence Tomography, as it is a well established tool for simulating light propagation in scattering media. However, in this method...
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A framework to analyse the probability of accidental hull girder failure considering advanced corrosion degradation for risk-based ship design
PublikacjaShip’s hull girder failure could result from maritime accident that can cause human life loss, environmental disaster, and major economic impacts. In risk-based ship design paradigm, accounting for rare phenomena (e.g. ship-ship collision or grounding) is important to provide safe and durable structure. In-service corrosion-induced hull degradation should be considered at the design stage, as it can significantly affect structural...
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Nanoparticles: Taking a Unique Position in Medicine
PublikacjaThe human nature of curiosity, wonder, and ingenuity date back to the age of humankind. In parallel with our history of civilization, interest in scientific approaches to unravel mechanisms underlying natural phenomena has been developing. Recent years have witnessed unprecedented growth in research in the area of pharmaceuticals and medicine. The optimism that nanotechnology (NT) applied to medicine and drugs is taking serious...
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Structural evaluation of percolating, self-healing polyurethane–polycaprolactone blends doped with metallic, ferromagnetic, and modified graphene fillers
PublikacjaComposites with differently shaped micro- and nanofillers show various, unique thermal, and physicochemical properties when mixed with carefully chosen polymer matrix. Selected composition holds strategic value in achieving desired properties that is biodegradability, thermoelectric conductivity, and shape memory for organic coating. The main aim of this work is to briefly examine structural changes after reaching percolation threshold...