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Search results for: nuclear wave function
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Investigation of Liquid–Gas Flow in a Horizontal Pipeline Using Gamma-Ray Technique and Modified Cross-Correlation
PublicationThis article presents the application of the radioisotope absorption method in the study of two-phase water–air flow in a horizontal pipe. The measurement principle and the test stand are briefly described. The main part of the article presents the signal analysis methods applied to data obtained from scintillation detectors. Because these signals are mostly stochastic waveforms, they were analyzed statistically using the cross-correlation...
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Wykładnicze równanie Arrheniusa jako funkcja dojrzałości twardniejącego betonu
PublicationPoprawne określenie funkcji dojrzałości dla mieszanki betonowej warunkuje powodzenie szacowania wytrzymałości na ściskanie na bazie pomiarów temperatury in situ. W artykule omówiono zastosowanie równania Arrheniusa do opisu funkcji dojrzewania twardniejącego betonu. Szczególną uwagę zwrócono na zależności szybkości zachodzenia reakcji w odmiennych warunkach temperaturowych. Przedstawiono wyniki własnych badań na kostkach zaprawy...
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Representation of magnetic hysteresis in a circuit model of a single-phase transformer
PublicationThe paper presents a mathematical model for the hysteresis phenomenon in a multi-winding single-phase core type transformer. The set of loop differential equations was developed for K-th winding transformer model where the flux linkages of each winding includes a flux common Φ to all windings as function of magneto motive force Θ of all windings. The first purpose of this paper is to determine a hysteresis nonlinearity involved...
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On Surface Kinetic Constitutive Relations
PublicationIn the framework of the strain gradient surface elasticity we discuss a consistent form of surface kinetic energy. This kinetic constitutive equation completes the statement of initial–boundary value problems. The proposed surface kinetic energy density is the most general function consistent with the constitutive relations in bulk. As the surface strain energy depends on the surface deformation gradient and its gradient, the kinetic...
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Accelerated Parameter Tuning of Antenna Structures by Means of Response Features and Principal Directions
PublicationPopularity of numerical optimization has been steadily on the rise in the design of modern antenna systems. Resorting to mathematically rigorous parameter tuning methods is a matter of practical necessity as interactive techniques (e.g., parameter sweeping) are no longer adequate when handling several performance figures over multi-dimensional parameter spaces. The most common design scenarios involve local tuning since decent...
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Immersive Technologies that Aid Additive Manufacturing Processes in CBRN Defence Industry
PublicationTesting unique devices or their counterparts for CBRN (C-chemical, B-biological, R-radiological, N-nuclear) defense relies on additive manufacturing processes. Immersive technologies aid additive manufacturing. Their use not only helps understand the manufacturing processes, but also improves the design and quality of the products. This article aims to propose an approach to testing CBRN reconnaissance hand-held products developed...
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Multipoint Ultrasonic Diagnostics System of Prestressed T-Beams
PublicationThis paper is devoted to the application of ultrasonic wave propagation phenomena for the diagnostics of prestressed, concrete, bridge T-beams. A multi-point damage detection system is studied with use of numerically obtained data. The system is designed to detect the presence of the material discontinuities as well as their location.
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Corrosion damage identification based on the symmetry of propagating wavefield measured by a circular array of piezoelectric transducers: Theoretical, experimental and numerical studies
PublicationThe article investigates the results obtained from numerical simulations and experimental tests concerning the propagation of guided waves in corroded steel plates. Developing innovative methodologies for assessing corrosion-induced degradation is crucial for accurately diagnosing offshore and ship structures exposed to harsh environmental conditions. The main aim of the research is to analyze how surface irregularities affect...
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DETERMINATION OF SEAKEEPING PERFORMANCE FOR A CASE STUDY VESSEL BY THE STRIP THEORY METHOD
PublicationThe increase of seakeeping performance is of particular importance for car and passenger ferries, service ships in the gas and oil extraction industry and offshore wind power farm industry, as well as for special purpose ships (including military applications). In the water areas of the Baltic Sea, North Sea, and Mediterranean Sea, which are characterised by a short and steep wave, the hull shape has a substantial impact on the...
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Adaptive CAD-Model Construction Schemes
PublicationTwo advanced surrogate model construction techniques are discussed in this paper. The models employ radial basis function (RBF)interpolation scheme or artificial neural networks (ANN) with a new training algorithm. Adaptive sampling technique is applied withrespect to all variables. Histograms showing the quality of the models are presented. While the quality of RBF models is satisfactory, theperformance of the ANN models obtained...
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Density smoothness estimation problem using a wavelet approach
PublicationIn this paper we consider a smoothness parameter estimation problem for a density function. The smoothness parameter of a function is defined in terms of Besov spaces. This paper is an extension of recent results (K. Dziedziul, M. Kucharska, B. Wolnik, Estimation of the smoothness parameter ). The construction of the estimator is based on wavelets coefficients. Although we believe that the effective estimation of the smoothness...
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The carrier capture and recombination processes in Ln/sup 3+/-activated scintillators
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Large area avalanche photodiodes in X-rays and light detection
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Timing properties of LuAP:Ce studied with large-area avalanche photodiodes
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Scintillation light trapping and radiation damage in CeF/sub 3/
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Methods of preparation and performance of sealed gas photomultipliers for visible light
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Perspectives for high resolution and high light output LuAP:Ce crystals
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Avalanche photodiodes in scintillation detection for high resolution PET
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CdWO/sub 4/ crystal in gamma-ray spectrometry
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Comparative study of avalanche photodiodes with different structures in scintillation detection
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Intrinsic energy resolution and light yield nonproportionality of BGO
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Study of pure nai at room and liquid nitrogen temperatures
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/sup 6/LiI(Eu) in neutron and /spl gamma/-ray spectrometry-a highly sensitive thermal neutron detector
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Non-proportionality and thermoluminescence of LSO:Ce
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LuAlO/sub 3/:Ce and other aluminate scintillators
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Large size LSO:Ce and YSO:Ce scintillators for 50 MeV range γ-ray detector
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New fast photomultipliers with a screening grid at the anode
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Low energy γ-rays scintillation detection with large area avalanche photodiodes
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Comparison of the scintillation properties of LSO:Ce manufactured by different laboratories and of LGSO:Ce
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Cerium-doped orthophosphates: new promising scintillators
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Evaluation of new photonis XP1472 nine-channel photomultiplier
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YSO, LSO, GSO and LGSO. A study of energy resolution and nonproportionality
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Toenail selenium level among healthy residents of two polish districts
PublicationCelem pracy było badanie zawartości selenu w próbkach paznokci pobranych od mieszkańców Województwa Pomorskiego i Lubuskiego. Wykazano, że średnie stężenia Se w próbkach paznokci wynosiło odpowiednio 0,57 ± 0,10, 0,60 ± 0,16 mg kg-1. Stwierdzono także, że płeć, wiek, wskaźnik masy ciała, status palenia oraz przyjmowanie Se w postaci suplementów diety przez uczestników badania wpływa istotnie statystycznie na poziom...
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Assessment of atmospheric inorganic pollution in the urban region of Gdańsk, Northern Poland
PublicationProjekt wykonano w przemysłowej części Gdańska w celu zidentyfikowania głównych źródeł zanieczyszczeń. Próbki suchego oraz żywego (w hodowli hydroponicznej) mchu eksponowano równolegle w celu określenia ich właściwości kumulacji w aspekcie badań biomonitoringowych. Analizę chemiczną składu próbek mchu wykonano dzięki zastosowaniu techniki aktywacji neutronowej i reaktorze badawczym w Delft (Holandia). Uzyskane wyniki wskazują,...
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The Unfolded Protein Response: A Double-Edged Sword for Brain Health
PublicationEfficient brain function requires as much as 20% of the total oxygen intake to support normal neuronal cell function. This level of oxygen usage, however, leads to the generation of free radicals, and thus can lead to oxidative stress and potentially to age-related cognitive decay and even neurodegenerative diseases. The regulation of this system requires a complex monitoring network to maintain proper oxygen homeostasis. Furthermore,...
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Technical Limitations in Merging Secular and Sacred Functions in Monumental Churches
PublicationThe abandonment of churches and their adaptation for secular purposes is a current subject in Europe and worldwide. Most cases involve objects that were desacralized and then rebuilt as a whole object for alternative functions. Thus far, the merging of secular and sacred functions in one monumental Catholic church has not raised any issues. The paper describes the case of St. Catherine’s Church in Gdansk, Poland, where sacred function...
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Evaluation of propagation parameters of open guiding structures with the use of complex root finding algorithms
PublicationAn efficient complex root tracing algorithm is utilized for the investigation of electromagnetic wave propagation in open guiding structures. The dispersion characteristics of propagated and leaky waves are calculated for a couple of chosen waveguides. The efficiency of the root tracing algorithm is discuses and compared to a global root finding algorithm.
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Zero-Pole Space Mapping for CAD of Filters
PublicationIn this paper, we propose a new space-mapping technique tailored to the CAD of microwave filters. The goal of space mapping is to achieve a satisfactory design with the minimal number of fine model evaluations. In our approach, the filter is represented by a rational function. To quickly align the coarse and fine models, and to speed up the direct optimization of the coarse model, we propose matching the zeros and poles of a rational...
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Multi-Option Model of Railway Traffic Organization Including the Energy Recuperation
PublicationThe article presents the issue of organization of railway traffic within the station, taking into account energy recuperation. We identified a number of factors which affect the energy efficiency of recuperation, including the issue of transfer of energy technology between a few vehicles. We presented some aspects of the decision problem of graphic train timetable construction with regard to recuperation. As an indicator of quality...
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Firing map for periodically and almost-periodically driven integrate-and-fire models: a dynamical systems approach
PublicationWe consider the Leaky Integrate-and-Fire and Perfect Integrator models of neuron’s dynamics with the input function being periodic and almost-periodic (in the sense of Stepanov). In particular we analyze properties and dynamics of the so-called firing map, which iterations give timings of consecutive spikes of a neuron. In case of a periodic input function we provide a detailed description of the sequence of interspike-intervals,...
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Możliwość oszacowania niezawodności silników o zapłonie samoczynnym z zastosowaniem teorii procesów semi-Markowa oraz podejmowania decyzji eksploatacyjnych z uwzględnieniem wiarygodności diagnozy o stanie technicznym tego rodzaju silników spalinowych = Possibility of estimating the reliability of diesel engines by applying the theory of semi-Markov processes and making operational decisions by considering reliability of diagnosis on technical state of this sort of combustion engines/
PublicationThe paper presents semi-Markov models of technical state transitions for diesel engines, useful for determining reliability of the engines. A possibility of application of a three-state model with a simplified matrix function, or even a two-state model, to determine reliability of the engines, has been described herein on examples of known from literature semi-Markov models, for the case when appropriate diagnosing systems (SDG)...
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On the Possibility of Increasing Ship Energy Efficiency Through Improved Propulsion Control System
PublicationThis paper summarizes the analyses conducted to assess the impact of the ship's propulsion control system on energy efficiency in calm, manoeuvre, and sea wave conditions, where the goal of the investigation is to develop new strategies for controlling the ship's motion while considering the interactions between the hull, engine, and propeller.
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Flood Routing by the Non-Linear Muskingum Model: Conservation of Mass and Momentum
PublicationIn this paper, the conservative properties of the Muskingum equation, commonly applied to solve river flood routing, are analysed. The aim of this analysis is to explain the causes ofthe mass balance error, which is observed in the numerical solutions of its non-linear form. The linear Muskingum model has been considered as a semi-discrete form of the kinematic wave equation and therefore it was possible to derive its two non-linear...
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Crank–Nicolson FDTD Method in Media Described by Time-Fractional Constitutive Relations
PublicationIn this contribution, we present the Crank-Nicolson finite-difference time-domain (CN-FDTD) method, implemented for simulations of wave propagation in media described by time-fractional (TF) constitutive relations. That is, the considered constitutive relations involve fractional-order (FO) derivatives based on the Grünwald-Letnikov definition, allowing for description of hereditary properties and memory effects of media and processes....
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Sounding of Layered Marine Bottom - Model Investigations
PublicationThe necessary actions connected with interpretations of examining of physical properties of sea bottom structure is developing of proper procedure of modeling of the layered structure. The implementation of the acoustic waves for the determination of seabed stratification requires a precise diagnosis of the topic from both the theoretical and practical side. Little differences between the parameters of sediments, as well as irregular...
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Detection of Objects Buried in the Sea Bottom with the Use of Parametric Echosounder
PublicationThe paper contains results of a in situ research main task of which was to detect objects buried, partially or completely, in the sea bottom. Object detecting technologies employing acoustic wave sources based on nonlinear interaction of elastic waves require application of parametric sound sources. Detection of objects buried in the sea bottom with the use of classic hydroacoustic devices such as the sidescan sonar or multibeam...
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Design and Experiments of a Piezoelectric Motor Using Three Rotating Mode Actuators
PublicationThis paper represents a numerical and experimental investigation of the multicell piezoelectric motor. The proposed design consists of three individual cells that are integrated into the stator, double rotor, and a preload system combined into a symmetrical structure of the motor. Each of the cells is characterized by a traveling wave and rotating mode motor. A finite element numerical analysis is carried out to obtain optimal...
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Solution of the dike-break problem using finite volume method and splitting technique
PublicationIn the paper the finite volume method (FVM) is presented for the solution of two-dimensional shallow water equations. These equations are frequently used to simulate the dam-break and dike-break induced flows. The applied numerical algorithm of FVM is based on the wave-propagation algorithm which ensures a stable solution and simultaneously minimizes the numerical errors. The dimensional decomposition according to the coordinate...
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Recent Developments in Data-Assisted Modeling of Flexible Proteins
PublicationMany proteins can fold into well-defined conformations. However, intrinsically-disordered proteins (IDPs) do not possess a defined structure. Moreover, folded multi-domain proteins often digress into alternative conformations. Collectively, the conformational dynamics enables these proteins to fulfill specific functions. Thus, most experimental observables are averaged over the conformations that constitute an ensemble. In this...
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Biomimetic torene shells
PublicationThe genome inside the eukaryotic cells is guarded by a unique shell structure, called the nuclear envelope (NE), made of lipid membranes. This structure has an ultra torus topology with thousands of torus-shaped holes that imparts the structure a high flexural stiffness. Inspired from this biological design, here we present a novel ‘‘torene’’ architecture to design lightweight shell structures with ultra-stiffness for engineering...