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Search results for: MULTIPLE SCATTERING EXPANSION
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Analytical calculations of scattering lengths for a class of long-range potentials of interest for atomic physics
PublicationWe derive two equivalent analytical expressions for an $l$th partial-wave scattering length $a_{l}$ for central potentials with long-range tails of the form % \begin{math} \displaystyle V(r)=-\frac{\hbar^{2}}{2m}\frac{Br^{n-4}}{(r^{n-2}+R^{n-2})^{2}} -\frac{\hbar^{2}}{2m}\frac{C}{r^{2}(r^{n-2}+R^{n-2})}, \end{math} % ($r\geqslant r_{s}$, $R>0$). % For $C=0$, this family of potentials reduces to the Lenz potentials discussed in...
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An Instantaneous Engine Speed Estimation Method Using Multiple Matching Synchrosqueezing Transform
PublicationInstantaneous rotational speed measurement of the engine is crucial in routine inspection and maintenance of an automobile engine. Since the contact measurement of rotational speed is not always available, the vibration measurement has been used for noncontact rotational speed estimation methods. Unfortunately, the accuracy of the noncontact estimation methods by analyzing engine vibration frequency is not satisfactory due to the...
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Experimental results of full scattering profile from finger tissue-like phantom
PublicationHuman tissue is one of the most complex optical media since it is turbid and nonhomogeneous. We suggest a new optical method for sensing physiological tissue state, based on the collection of the ejected light at all exit angles, to receive the full scattering profile. We built a unique set-up for noninvasive encircled measurement. We use a laser, a photodetector and finger tissues-mimicking phantoms presenting different optical...
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Measurements of Spectral Spatial Distribution of Scattering Materials for Rear Projection Screens used in Virtual Reality Systems
PublicationRapid development of computing and visualisation systems has resulted in an unprecedented capability to display, in real time, realistic computer-generated worlds. Advanced techniques, including three-dimensional (3D) projection, supplemented by multi-channel surround sound, create immersive environments whose applications range from entertainment to military to scientific. One of the most advanced virtual reality systems are CAVE-type...
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An Analysis of Scattering from Ferrite Post of Arbitrary Convex Cross Section with the Use of Field Matching Method
PublicationA problem of electromagnetic wave scattering from ferrite post is presented. The post is assumed to be located in closed areas as waveguide junction, or in open area illuminated by a plane wave. The object is of arbitrary convex cross section and the method of analysis is semi-analytical, based on the direct field matching technique.
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BC-MPI: running an mpi application on multiple clusters with beesycluster connectivity
PublicationW artykule zaproponowano nowy pakiet BC-MPI, który umożliwiauruchomienie aplikacji MPI na wielu klastrach z różnymi implementacjami MPI. Wykorzystuje dedykowane implementacje MPIdo komunikacji wewnątrz klastrów oraz tryb MPI THREAD MULTIPLE dokomunikacji pomiędzy klastrami w dodatkowych wątkach aplikacji MPI. Ponadto, aplikacja BC-MPI może być automatycznie skompilowanai uruchomiona przez warstwę pośrednią BeesyCluster. BeesyClusterumożliwia...
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On weakly dispersive multiple-trapping transport
PublicationPodano przybliżone rozwiązania równań transportu nośników ładunku dla modelu wielokrotnego pułapkowania, odnoszących się do metody czasu przelotu - przy założeniu, że większość nośników znajduje się w stanie termicznej quasi równowagi. Otrzymane rozwiązania zweryfikowano przy pomocy obliczeń metodą Monte Carlo dla wykładniczego i gaussowskiego rozkładu pułapek. Zaproponowano nową metodę wyznaczania profilu energetycznego pułapek...
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Hybrid energy storage forelectric multiple units to operate at the partially electrified line Gdynia -Hel
PublicationThe article presents calculations enabling the selection of an on-board energy storage device to replace diesel-powered trains with modern storage multiple units on the example railway line Gdynia Główna -Hel. The pioneering and currently used storage electric multiple units, mainly in Europe, were presented. The condensed results of the inventory of the line in question, including the technical condition...
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Nonadditivity of quantum and classical capacities for entanglement breaking multiple-access channels and the butterfly network
PublicationWe analyze quantum network primitives which are entanglement breaking. We show superadditivity of quantum and classical capacity regions for quantum multiple-access channels and the quantum butterfly network. Since the effects are especially visible at high noise they suggest that quantum information effects may be particularly helpful in the case of the networks with occasional high noise rates. The present effects provide a qualitative...
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Low-energy positron scattering from gas-phase pyrimidine: A quantum treatment of the dynamics and a comparison with experiments
PublicationWe are reporting detailed quantum scattering calculations that describe the diffusion of a beam of low-energy positrons interacting with the pyrimidine target as a gas-phase partner. The calculations have employed an essentially ab initio model for the short-range correlation interaction and for the electrostatic interaction of an impinging positron and the electron+nuclear structure of the target molecule at its equilibrium geometry.
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Electron Scattering on X(CH3)4 Molecules: Applicability of Simple Additivity Rule and Role of Methylation
PublicationTo investigate influence of target methylation (substitution of a hydrogen atom by methyl group) on electron-collision processes we compare absolute total cross sections for XH4 and X(CH3)4 molecules, where X is Si and Ge, respectively. We also compare experimental TCSs energy dependencies with estimated data obtained using simple formula and TCSs for methyl group and those for SiH4 and GeH4. Electron-scattering TCSs for mentioned...
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Subadditivity of the minimum output entropy and superactivation of the classical capacity of quantum multiple access channels
PublicationWe study subadditivity of the minimum output entropy (Hmin) of quantum multiple access channels (MACs). We provide an example of violation of the additivity theorem for Hmin known in classical information theory. Our result is based on a fundamental property of MACs, i.e., independence of each sender. The channels used in the example can be constructed explicitly. On the basis of subadditivity of Hmin we also provide an example...
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Designing acoustic scattering elements using machine learning methods
PublicationIn the process of the design and correction of room acoustic properties, it is often necessary to select the appropriate type of acoustic treatment devices and make decisions regarding their size, geometry, and location of the devices inside the room under the treatment process. The goal of this doctoral dissertation is to develop and validate a mathematical model that allows predicting the effects of the application of the scattering...
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Magnetizability of the relativistic hydrogenlike atom in an arbitrary discrete energy eigenstate: Application of the Sturmian expansion of the generalized Dirac-Coulomb Green function
PublicationThe Sturmian expansion of the generalized Dirac--Coulomb Green function [R.\/~Szmytkowski, J.\ Phys.\ B 30 (1997) 825; erratum 30 (1997) 2747] is exploited to derive a closed-form expression for the magnetizability of an arbitrary discrete state of the relativistic one-electron atom with a point-like, spinless and motionless nucleus of charge $Ze$. The result has the form of a double finite sum involving the generalized hypergeometric...
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Uniform expansion estimates in the cubic map as a function of the parameter
Open Research DataThis dataset contains selected results of numerical computations described in the paper "Quantitative hyperbolicity estimates in one-dimensional dynamics" by S. Day, H. Kokubu, S. Luzzatto, K. Mischaikow, H. Oka, P. Pilarczyk, published in Nonlinearity, Vol. 21, No. 9 (2008), 1967-1987, doi: 10.1088/0951-7715/21/9/002.
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A Measurement System for Quasi-Spectral Determination of Absorption and Scattering Parameters of Veterinary Tissue Phantoms
PublicationThis paper describes the construction of a system for the quasi-spectral determination of absorption and scattering parameters of animal tissue phantoms. Several tissue phantoms, including one reference and two modified for examination, were prepared from polydimethylsiloxane (PDMS). The phantoms were measured using a system based on an integrating sphere and the light sources of wavelengths commonly used for the treatment of various...
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Impact of cross-section centers estimation on the accuracy of the Point cloud spatial expansion using robust M-estimation and Monte Carlo simulation
PublicationThe point cloud spatial expansion (PCSE) method creates an alternative form of representing the shape of symmetrical objects and introduces additional descriptive geometric parameters. An important element of the procedure is determining the course of the axis of symmetry of cylindrical objects based on cross-sections of point clouds. Outliers occurring in laser measurements are of great importance in this case. In this study,...
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Multiple jets impingement – numerical analysis by the ζ-f and hybrid VLES turbulence models
PublicationPresented paper summarizes the Authors findings referring to the numerical analyses of the jet impinging phenomena in the case of complex jets configurations in various applications e.g. in the heat exchangers. Multiple jets interference resulting in the cross-flow and the surface curvature are the factors which impose the need of advanced turbulence models utilization. The outcome of the research based on the ζ-f turbulence model...
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A method for testing the wide-sense stationary uncorrelated scattering assumption fulfillment for an underwater acoustic channel
PublicationWide-sense stationary and uncorrelated scattering (WSSUS) assumptions are often applied for the statistical description of wireless communication channels. However, in the case of underwater acoustic channels the WSSUS model is of limited value. The degree of similarity of in-phase and quadrature components of the channel impulse response, measured with the use of bandpass modulated signals, can be used as an indicator of WSSUS...
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The basis set, scattering wavefunction and Schwinger variational principle: an application for low energy positron-atom scattering
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Low-energy positron scattering from DNA nucleobases: the effects from permanent dipoles
PublicationAb initio quantum calculations for low-energy positron scattering from gas-phase isolated molecular nucleobases which are part of the DNA structure are presented and discussed over the range of 1 eV to 25 eV. The calculations report the integral cross sections (ICSs) and the momentum-transfer cross sections (MTCSs) for Adenine, Guanine, Thymine and Cytosine. The calculations show very clearly the important role of the dominant...
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Multiple Reprocessing of Conductive PLA 3D-Printing Filament: Rheology, Morphology, Thermal and Electrochemical Properties Assessment
PublicationAdditive manufacturing technologies are gaining more and more attention, resulting in the development or modification of 3D printing techniques and dedicated materials. On the other hand, economic and ecological aspects force the industry to develop material recycling strategies. In this work, the multiple reprocessing of a commercially available PLA conductive composite with carbon black filler, dedicated to 3D printing, was investigated....
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Electron Scattering from Methyl Formate (HCOOCH3): A Joint Theoretical and Experimental Study
PublicationElastic low-energy electron collisions with methyl formate have been studied theoretically at the level of various theories. The elastic integral cross section was calculated using Schwinger multichannel and R-matrix methods, in the static-exchange and static-exchange plus polarization levels of approximations for energies up to 15 eV. The absolute total cross section for electron scattering from methyl formate has been measured...
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Quasi-analytical Near-to-Far Field Transformation Based on Field Matching Method for Scattering Problems
PublicationA new quasi-analytical near-to-far field transformation based on field matching method (field expansion in a base of Hankel functions) is presented. This approach uses finite element method to obtain near field, then the field is expressed in a base of Hankel functions. The evaluated coefficients allow to calculate the field outside the numerical domain, also in a far distance. The main advantage of the proposed technique is avoiding of...
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Magnetic-field-induced electric quadrupole moments for relativistic hydrogenlike atoms: Application of the Sturmian expansion of the generalized Dirac-Coulomb Green function
PublicationWe consider a Dirac one-electron atom placed in a weak, static, uniform magnetic field. We show that, to the first order in the strength of the external field, the only electric multipole moments, which are induced by the perturbation in the atom, are those of an even order. Using the Sturmian expansion of the generalized Dirac-Coulomb Green function we derive a closed-form expression for the electric quadrupole moment induced...
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Leszek Ziemczonek dr
PeopleUniversity education 1973-1978 – Nicolaus Copernicus University in Toruń, University of Gdańsk in Gdańsk, Mathematical Physics, M. Sc. 1979 – Diploma of Postgraduate Studies, Pedagogics 1989 – Institute of Physics, Polish Academy of Sciences in Warsaw, Theoretical Physics, Ph. D. 2010-2012 – Diploma of Postgraduate Studies, Mathematics Training: · 09.1983 – Trieste (Italy) – International Centre for Theoretical Physics...
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SmallAngle Neutron Scattering Study of the Structure of Mixed Micellar Solutions Based on Nonionic and Two Cationic Surfactants
PublicationThe aggregation in mixed water systems based on nonionic surfactant, i.e., heptaethylene glycol monotetradecyl ether (C14E7), and cationic surfactants, i.e., cetyltrimethylammonium bromide (CTAB), and cetyltrimethylammonium chloride (CTAC) has been investigated using the smallangle neutron scattering method. The preliminary results of the study of the behavior of C14E7 aqueous solutions (for a concentration of 0.17%) when adding...
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Scattering of electrons from acetaldehyde and acetone
PublicationZmierzono całkowity przekrój czynny (TCS) na rozproszenie elektronów na drobinach acetaldehydu (CH3)CHO oraz acetonu (CH3)2CHO w zakresie energii zderzenia 0.7 - 400 eV. Charakter otrzymanych zależności energetycznych TCS jest typowy dla drobin o wysokim momencie dipolowym. Wyniki porównano z przekrojami czynnymi dla izomerów cyklicznych odpowiadających obu drobinom.
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Eigenchannel method in quantum potential scattering.
PublicationUogólniono metodę fal cząstkowych na przypadek kwantowego rozpraszania na dowolnym potencjale krótkozasięgowym. Zaprezentowano formalizm ogólny oraz jego zastosowania do cząstek Schrodingera i Duraca.
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Measurements of electron scattering in the backward direction
PublicationPrzedstawiono wyniki badań rozproszenia elektronów na atomach i cząsteczkach przeprowadzonych w zakresie dużych kątów rozproszenia do 180o.
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Positron scattering by the Ar2 and Xe2 dimers
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RAMAN SCATTERING TENSORS FOR ICE Ih
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Programmable Input Mode Instrumentation Amplifier Using Multiple Output Current Conveyors
PublicationIn this paper a programmable input mode instrumentation amplifier (IA) utilising second generation, multiple output current conveyors and transmission gates is presented. Its main advantage is the ability to choose a voltage or current mode of inputs by setting the voltage of two configuration nodes. The presented IA is prepared as an integrated circuit block to be used alone or as a sub-block in a microcontroller or in a field...
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Expansion of the self of activists and nonactivists involved in mass gatherings for collective action
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The expansion wave of an invasive predator leaves declining waterbird populations behind
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A multirate approach to DDS algorithm versus Taylor-series expansion technique.
PublicationPokazano, że cyfrowy generator syntezy bezpośredniej (DDS) można traktować jako algorytm wieloszybkościowy. Rozważono i porównano dwa sposoby wykorzystania pamięci. W pierwszym z nich zastosowano filtr ułamkowo-opóźniający o strukturze Farrowa. Drugie podejście oparto na rotacji fazy na podstawie rozwinięcia w szereg Taylora. Eksperymenty pokazują, że za pomocą obu tych sposobów, dla sinusoidy zespolonej generowanej w kwadraturowym...
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Multiple group membership and collective action: study 1&2
Open Research DataDatasets from two studies, conducted in Poland, on the relation between identity fusion, group identification, multiple group membership, perceived injustice, and collective action intention. The purpose of the present studies was to examine (a) whether multiple group membership (in the context of opinion-based groups) relates to collective action (CA)...
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Conditions for Multiple Acquisition of Echoes from Stationary Targets in Successive Transmissions of Active Sonars
PublicationIn echolocation, the highest possible number of contacts with a detected target is clearly decisive on the possibilities of echo processing to optimise the estimation of distinctive characteristics of the observed target. In hydrolocation, the slow propagation of acoustic waves in water reduces the number of contacts of echosounders and sonars with detected targets. The article considers model conditions for acquiring multiple...
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Employees’ self-expansion, work conditions, work engagement and productive behaviours: study 1&2
Open Research DataIn the following studies conducted in Poland, we examined the importance of workplace self-expansion and found that it is a significant mediator between job resources (e.g. compensation and benefits, job tasks) and work engagement (Study 1) as well as task-oriented engagement (Study 2). At the same time, our findings prove that job demands (e.g. role...
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Dynamics study on single and multiple β-sheets
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Psychological consequences of multiple sclerosis and assistance possibilities
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Multiple Criteria Analysis of European Union Agriculture
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Computer analysis of multiple-choice examination documents
PublicationOpisany system AATE wyposażony jest w edytor testów, za pomocą którego egzaminator przygotowuje test egzaminacyjny. Utworzony test ze swoimi parametrami jest pamiętany w bazie danych i następnie może być wydrukowany. Po przeprowadzeniu egzaminu wypełnione formularze za pomocą skanera z podajnikiem wprowadza się do komputera. W komputerze system analizuje formularze i odczytane odpowiedzi porównuje się z wzorcami przechowywanymi...
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Multiple frequency tracker with improved tracking Capabilities
PublicationW pracy zaproponowano prostą modyfikację znanego z literatury wieloczęstotliwościowego adaptacyjnego filtra wycinającego, prowadzącą do istotnej poprawy jego charakterystyk nadążania.
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Quantum superadditivity in linear optics networks: Sending bits via multiple-access Gaussian channels
PublicationSuperadditivity effects of communication capacities are known in the case of discrete variable quantum channels. We describe the continuous variable analog of one of these effects in the framework of Gaussian multiple access channels (MACs). Classically, superadditivity-type effects are strongly restricted: For example, adding resources to one sender is never advantageous to other senders in sending their respective information...
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Image transmission in UAV MIMO UWB-OSTBC system over Rayleigh channel using multiple description coding (MDC)
PublicationOrthogonal Space-Time Block Codes (OSTBC) and multiple-input-multiple-output (MIMO) communication system are new techniques with high performance that have many applications in wireless telecommunications. This chapter presents an image transfer technique for the unmanned aerial vehicle (UAV) in a UWB system using a hybrid structure of the MIMO-OSTBC wireless environment in multiple description coding (MDC) deals. MDC technique...
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Electromagnetic plane wave scattering from a cylindrical object with an arbitrary cross section using a hybrid technique
PublicationA hybrid technique combining finite-element and mode-matching methods for the analysis of scattering problems in open and closed areas is presented. The main idea of the analysis is based on the utilization of the finite-element method to calculate the post impedance matrix and combine it with external excitation. The discrete analysis, which is the most time- and memory-consuming, is limited here only to the close proximity of...
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Multiple myeloma - Male, 37 - Tissue image [5020730020699181]
Open Research DataThis is the histopathological image of BONES, JOINTS AND ARTICULAR CARTILAGE OF OTHER AND UNSPECIFIED SITES tissue sample obtained in Medical University Gdańsk and deposited in ZMDL-GUMED. The sample image was taken using: Pannoramic 250 3DHistech slide scanner (20x magnification) and saved to DICOM format.
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Multiple myeloma - Male, 37 - Tissue image [6270730022334531]
Open Research DataThis is the histopathological image of BONES, JOINTS AND ARTICULAR CARTILAGE OF OTHER AND UNSPECIFIED SITES tissue sample obtained in Medical University Gdańsk and deposited in ZMDL-GUMED. The sample image was taken using: Pannoramic 250 3DHistech slide scanner (20x magnification) and saved to DICOM format.
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Multiple myeloma - Male, 37 - Tissue image [5020730020693581]
Open Research DataThis is the histopathological image of BONES, JOINTS AND ARTICULAR CARTILAGE OF OTHER AND UNSPECIFIED SITES tissue sample obtained in Medical University Gdańsk and deposited in ZMDL-GUMED. The sample image was taken using: Pannoramic 250 3DHistech slide scanner (20x magnification) and saved to DICOM format.