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Canonical perturbation theory for inhomogeneous systems of interacting fermions
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Saint-Venant torsion based on strain gradient theory
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Energy Management in an Islanded Microgrid: A Consensus Theory Approach
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Ships Shore Service Optimization Using the Queueing Theory
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Ingoing and outgoing waves in the non-relativistic theory of photoionization
PublicationZastosowano rachunek zaburzeń zależny od czasu do wyprowadzenia wzoru na różniczkowy przekrój czynny na fotojonizację nierelatywistycznego kwantowego układu jednoelektronowego płaską monochromatyczną falą elektromagnetyczną. Pokazano,że pochodzenie oraz asymptotykę tzw. ''funkcji falowej stanu końcowego'', wchodzącej do tego wzoru, można wytłumaczyć bez odwoływania się do kontrowersyjnej argumentacji podanej przez Breita i Bethego.
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Nonlinear waves in optical waveguides and soliton theory applications
PublicationRównania teorii solitonów zastosowano do propagacji impulsów światła w falo-wodach dielektrycznych.Wyprowadzono i zbadano rozwiazania równań oddziaływa-nia (z uwzględnieniem tłumienia) trzech fal Maxwella-Blocha.
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Quantum morphogenesis: A variation on Thom`s catastrophe theory.
PublicationZaproponowano nowy opis morfogenezy na poziomie kwantowym w oparciu o rozwiązania samo przełączające nieliniowego równania von Neumanna.
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Saint-Venant torsion based on strain gradient theory
PublicationIn this study, the Saint-Venant torsion problem based on strain gradient theory is developed. A total form of Mindlin's strain gradient theory is used to acquire a general Saint-Venant torsion problem of micro-bars formulation. A new Finite Element formulation based on strain gradient elasticity theory is presented to solve the Saint-Venant torsion problem of micro-bars. Moreover, the problem is solved for both micro and macro...
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Coupled nonlinear Schrödinger equations in optic fibers theory
PublicationIn this paper a detailed derivation and numerical solutions of CoupledNonlinear Schr¨odinger Equations for pulses of polarized electromagnetic wavesin cylindrical fibers has been reviewed. Our recent work has been compared withsome previous ones and the advantage of our new approach over other methods hasbeen assessed. The novelty of our approach lies is an attempt to proceed withoutloss of information within the frame of basic...
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On exact dynamic continuity conditions in the theory of branched shells
PublicationSformułowano ścisłe, wypadkowe, dynamiczne warunki ciągłości wzdłuż powierzchniowej krzywej osobliwej modelującej rozwidlenie w konstrukcji powłokowej. Warunki zostały wyprowadzone poprzez ścisłe całkowanie po grubości powłoki globalnych warunków równowagi mechaniki ośrodka ciągłego.
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Theory vs. practice. Searching for a path of practical education
PublicationThe introduction of a three-tier model of higher education (the Bologna model) has led to considerable changes in the 1st- and 2nd-tier technical courses at universities. At present, a student with a bachelor’s degree can be employed in his / her profession after completing only 7 semesters of study. A search is under way for methods of combining theoretical knowledge taught at universities with practical knowledge gained afterwards....
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On constitutive relations in the resultatnt non-linear theory of shells
PublicationThe authors summarize their current research in the field of constitutive modelling in the framework of non-linear 6-parameter shell theory. In particular the description of isotropic, multilayered composite and functionally graded shells is presented.
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Analysis of elementary cellular automata using the theory of conflict
PublicationThe paper contains decomposition of elementary cellular automata (ECA in short) to subsystems that are defined according to a new theory called theory of conflict (ToC in short). The decomposition is a completely new approach to analysis of ECA and complex systems in general.
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On practical application of Shannon theory to character recognition and more
PublicationLet us consider an optical character recognition system, which in particular can be used for identifying objects that were assigned strings of some length. The system is not perfect, for example, it sometimes recognizes wrongly the characters "Y" and "V". What is the largest set of strings of given length for the system under consideration, which can be mutually correctly recognized, and the corresponding objects correctly identified?...
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Optimal linear control theory in power system application
PublicationPrzedstawiono syntezę stabilizatora systemowego przy wykorzystaniu metodyki Hinf. Zaprojektowany regulator umożliwia uzyskanie lepszych rezultatów w porównaniu z regulatorem odniesienia w szerokim zakresie zmian punktu pracy.
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From fluid mechanics backgrounds to modern field theory
PublicationOur presentation keeps a historical line of reasoning, since we start from old concepts of fluid mechanics and finish on concepts of modern field theory. We want to show that some facts from the nature phenomena, which have firstly been discovered on the ground of fluid mechanics, were next incorporated into physics and later become the important pattern for whole mathematical physics. Especially, well-known continuum models, which...
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Sustainable development on the background of a general theory of regional development
PublicationThe article focuses on a presentation and discussion of the concept of "sustainable de-velopment" (SD). It contains an analysis of the concept, its characteristics, objectives and principles of implementation. Particular emphasis has been placed on presentation of the unique features of sustainable development that distinguish it from other theories of regional development. Therefore, the discussion has been preceded by a discussion...
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Networkig activities of general judiciary - from theory to practice
PublicationOver the last three decades, networks - as a field of research - have acquired a significant place among management sciences. Unfortunately, in the judiciary they have become a subject of more careful analyses only recently, which resulted in a large discrepancy of knowledge - both in theory and in its practical adaptation for the needs of the courts. In order to fill this cognitive gap, an attempt was made to identify levels of...
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Steering is an essential feature of non-locality in quantum theory
PublicationA physical theory is called non-local when observers can produce instantaneous effects over distant systems. Non-local theories rely on two fundamental effects: local uncertainty relations and steering of physical states at a distance. In quantum mechanics, the former one dominates the other in a well-known class of non-local games known as XOR games. In particular, optimal quantum strategies for XOR games are completely determined...
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Application of Game Theory to Conflict Management in a Construction Contract
PublicationInterest has recently grown in the application of game theory (GT) to solve a number of diverse problems in the field of construction. The use of GT by a general contractor (GC) of construction works to indicate the best strategy leading to winning court proceedings in a situation of conflict with investor (IN), has not been investigated until now. Thus the aim of this paper is to indicate the optimal strategy from the GC viewpoint...
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On Nonlinear Dynamic Theory of Thin Plates with Surface Stresses
PublicationWe discuss the modelling of dynamics of thin plates considering surface stresses according to Gurtin–Murdoch surface elasticity. Taking into account the surface mass density we derive the two-dimensional (2D) equations of motion. For the reduction of the three-dimensional (3D) motion equations to the 2D ones we use the trough-the-thickness integration procedure. As a result, the 2D dynamic parameters of the plate depend not only...
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Electromagnetic-based derivation of fractional-order circuit theory
PublicationIn this paper, foundations of the fractional-order circuit theory are revisited. Although many papers have been devoted to fractional-order modelling of electrical circuits, there are relatively few foundations for such an approach. Therefore, we derive fractional-order lumped-element equations for capacitors, inductors and resistors, as well as Kirchhoff’s voltage and current laws using quasi-static approximations of fractional-order...
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The ONETEP linear-scaling density functional theory program
PublicationWe present an overview of the ONETEP program for linear-scaling density functional theory (DFT) calculations with large basis set (planewave) accuracy on parallel computers. The DFT energy is computed from the density matrix, which is constructed from spatially localized orbitals we call Non-orthogonal Generalized Wannier Functions (NGWFs), expressed in terms of periodic sinc (psinc) functions. During the calculation, both the...
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On the effective properties of foams in the framework of the couple stress theory
PublicationIn the framework of the couple stress theory, we discuss the effective elastic properties of a metal open-cell foam. In this theory, we have the couple stress tensor, but the microrotations are fully described by displacements. To this end, we performed calculations for a representative volume element which give the matrices of elastic moduli relating stress and stress tensors with strain and microcurvature tensors.
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On Applications of Elements Modelled by Fractional Derivatives in Circuit Theory
PublicationIn this paper, concepts of fractional-order (FO) derivatives are reviewed and discussed with regard to element models applied in the circuit theory. The properties of FO derivatives required for the circuit-level modeling are formulated. Potential problems related to the generalization of transmission-line equations with the use of FO derivatives are presented. It is demonstrated that some formulations of FO derivatives have limited...
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Analytical design method for widening the intertrack space
PublicationThe paper involved the issue of arching of the railway turnouts. This is an issue which is given relatively less attention to scientific and research activities. Reference has been made to the book by Wladyslaw Rzepka, under the title „Curved turnouts in plan and profile”, which has been used in Poland for more than 50 years as the main source of information relating to the turnouts on the curve. The book is a compilation of elaborations...
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Arching of railway turnouts by analytical design method
PublicationThe paper involved the issue of arching of the railway turnouts. This is an issue which is given relatively less attention to scientific and research activities. Reference has been made to the book by Wladyslaw Rzepka, under the title „Curved turnouts in plan and profile”, which has been used in Poland for more than 50 years as the main source of information relating to the turnouts on the curve. The book is a compilation of elaborations...
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Electro-mechanical shear buckling of piezoelectric nanoplate using modified couple stress theory based on simplified first order shear deformation theory
PublicationThis paper studies the electro-mechanical shear buckling analysis of piezoelectric nanoplate using modified couple stress theory with various boundary conditions.In order to be taken electric effects into account, an external electric voltage is applied on the piezoelectric nanoplate. The simplified first order shear deformation theory (S-FSDT) has been employed and the governing differential equations have been obtained using...
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pH gradient high-performance liquid chromatography: theory and applications
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The Poland-United States Security Relations in the light of Asymmetry Theory
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On kinematics in the theory of multiphase media, comparison between two traditions
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Modeling of production planning and control process consistent with theory of constraint
PublicationArtykuł dotyczy problematyki zastosowania metody werbel-bufor-lina do planowania produkcji w systemach produkcyjnych z wielokrotnymi buforami. W artykule przedstawiono algorytm - jego funkcje, dane wejściowe i wyjściowe - który może mieć zastosowanie do modelowania procesu planowania i sterowania produkcją. Algorytm umożliwia określenie wielkości czasowych buforów w systemie oraz terminów rozpoczęcia i zakończenia realizacji zadań....
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Scheduling Repetitive Construction Processes Using the Learning-Forgetting Theory
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On shear correction factors in the non-linear theory of elastic shells
PublicationW pracy wyprowadzono analitycznie wartości korekcyjnych współczynników ścinania dla ścinania poprzecznego oraz dla momentów owinięcia w ramach nieliniowej sześcioparametrowej teorii powłok. Wartości wyprowadzono poprzez odpowiednie sformułowanie komplementarnej energii sprężystej. Na drodze analizy przy pomocy MES, badano wpływ wartości współczynników na położenie punktów bifurkacji, deformacje, całkowitą energię sprężystą układu...
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Moddeling urban processes based on requirements ofself-organization theory.
PublicationW artykule przedstawiono ogólne podstawy symulacji rozwoju urbanistycznego w oparciu o modele komórkowe. Nowa teoria, wykorzystująca aparat matematyczny stworzony do badań i modelowania dynamiki układów nieliniowych, rozszerza również możliwości poznawcze i wykorzystanie systemów GIS w szeroko pojmowanym planowaniu przestrzennym. Jej szybki rozwój w ostatnich latach i niezwykłe osiągnięcia w poznaniu procesów rządzących podstawową...
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Seafloor backscattering: numerical simulation vs. filter theory approach.
PublicationPrzedstawiono model opisujący rozpraszanie sygnału akustycznego na nierównomiernej, regularnie sfalowanej powierzchni dna morskiego jako filtr liniowy z odpowiedzią impulsową o zmieniającej się w czasie chwilowej dominującej częstotliwości. Porównano przewidywania modelu z wynikami otrzymanymi w wyniku złożonych obliczeniowo symulacji numerycznych opartych na fizycznym modelu zjawiska wykorzystującym aproksymację Kirchhoffa. Wstępnie...
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Theory of scattering by an array of lossy dielectric, ferrite and conducting cylinders.
PublicationOpisano metodę analizy umożliwiającą określenie zastępczego pola rozproszonego od dowolnej konfiguracji prętów dielektrycznych, ferrytowych lub metalowych na zewnętrznym obszarze cylindrycznym w celu połączenia go z wybranym pobudzeniem i znalezienia macierzy rozproszenia układu. Prezentowane podejście znajduje zastosowanie w analizie struktur zamkniętych i określanie macierzy rozpraszania złączy falowodowych jak i otwartych...
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Interaction of modes in nonlinear acoustics: theory and applications to pulse dynamics.
PublicationOgólna teoria oddziaływania modów hydrodynamicznych opiera się na wyprowadzeniu równań różniczkowych nieliniowych. Mody rozumiane są tu jako wektory własnych układów praw zachowań hydrodynamicznych. Rozpatrywano zjawiska towarzyszące fali akustycznej w przepływie lepkim nieliniowym. Uwzględniono płyny w każdym fizycznym równaniu stanu.
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Thermodynamically consistent gradient theory of damage coupled with gradient plasticity
PublicationPrzedstawiono termodynamicznie zgodną teorię plastycznego zniszczenia w zakresie mechaniki Newtona-Eshelbego. Poza klasycznymi równaniami ruchu w przestrzeni fizycznej sformułowano dynamiczne równania równowagi sił powiązanych z defektami w przestrzeni materialnej oraz pierwsze i drugie prawo termodynamiki w przestrzeni fizycznej i materialnej. Ogólne równania konstytutywne przyjęto jako funkcję gradientu deformacji, jego składników...
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Theory versus experiment for vacuum Rabi oscillations in lossy cavities
PublicationThe 1996 experiment by Brune et al. [Phys. Rev. Lett. 76, 1800 (1996)] on vacuum Rabi oscillation is analyzed by means of alternative models of atom-reservoir interaction. Agreement with experimental Rabi oscillation data can be obtained if one defines jump operators in the dressed-state basis and takes into account thermal fluctuations between dressed states belonging to the same manifold. Such low-frequency transitions could...
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Analysis of the objects images on the sea using Dempster-Shafer Theory
PublicationThe paper presents the concept of using aerial and satellite imagery or images coming from the marine radar to identify and track vessels at sea. The acquired data were subjected to a highly advanced image analysis. The development of remote sensing techniques allows to gain a huge amount of data. These data are useful information source however usually we have to use different data mining methods to gain interested information....
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Elastoplastic law of Cosserat type in shell theory with drilling rotation
PublicationWithin the framework of six-parameter non-linear shell theory, with strain measures of the Cosserat type, we develop small-strain J2-type elastoplastic constitutive relations. The relations are obtained from the Cosserat plane stress relations assumed in each shell layer, by through-the-thickness integration employing the first-order shear theory. The formulation allows for unlimited translations and rotations. The constitutive...
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THE INFLUENCE OF GESTALT THEORY ON ERNST CASSIRER’S PHENOMENOLOGY OF SYMBOLIC FORMS
PublicationIn the opinion of many scholars the notion of symbolic pregnancy is one of the key concepts in Ernst Cassirer’s philosophy of symbolic forms. Without a proper under-standing of its conceptual frame Cassirer’s philosophy lacks a consistent foundation. The notion symbolic pregnancy offers the mechanism of distinction of symbolic forms. The newest investigations (also in unpublished or less known, neglected writings of the philosopher)...
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Normal-form preemption sequences for an open problem in scheduling theory
PublicationStructural properties of optimal preemptive schedules have been studied in a number of recent papers with a primary focus on two structural parameters: the minimum number of preemptions necessary, and a tight lower bound on shifts, i.e., the sizes of intervals bounded by the times created by preemptions, job starts, or completions. These two parameters have been investigated for a large class of preemptive scheduling problems,...
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Elastoplastic material law in 6-parameter nonlinear shell theory
PublicationWe develop the elastoplastic constitutive relations for nonlinear exact 6-parameter shell theory. A J2-type theory with strain hardening is formulated that takes into account asymmetric membrane strain measures. The incremental equations are solved using implicit Euler scheme with closest point projection algorithm. The presented test example shows the correctness of the proposed approach. Influence of micropolar material parameters...
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On refined constitutive equations in the six-field theory of elastic shells
PublicationWithin the resultant six-field shell theory, the second approximation to the complementary energy density of an isotropic elastic shell undergoing small strains is constructed. In this case, the resultant drilling couples are expressed explicitly by the stress resultants and stress couples as well as by amplitudes of the quadratic and cubic distributions of an intrinsic deviation vector. The refined 2D strain-stress and stress-strain...
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Application of percolation theory for description of electrical properties of conducting coatings
PublicationPrzedstawiono pomiary elektryczne i elektrochemiczne powłok organicznych przewodzących prąd elektryczny i mogących pełnić rolę anody w systemie ochrony katodowej żelbetonu. Za pomocą pomiarów impedancyjnych dokonano oceny rezystancji powłoki w funkcji zawartości grafitu. Na tej podstawie oszacowano próg perkolacji powłoki epoksydowej domieszkowanej elektrografitem. Ocenę obciążalności prądowej powłok przewodzących dokonano wykonując...
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On the FEM implementation of the large rotation shell theory for elasticanisotropic shells.
PublicationW pracy przedstawiono problemy implementacji MES teorii powłok o dużych obrotach w statycznej, geometrycznie nieliniowej analizie konstrukcji warstwowych. Zwrócono uwagę na właściwą interpretacje rotacyjnych stopni swobody w algorytmie MES. Omówiono wariant dużych i skończonych obrotów. Przedstawiono wyniki obliczeń dla znanego w literaturze przykładu analizy paneli kompozytowej w zakresie dużych obrotów.
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On the Equations of the Surface Elasticity Model Based on the Theory of Polymeric Brushes
PublicationMotivating by theory of polymers, in particular, by the models of polymeric brushes we present here the homogenized (continual) two-dimensional (2D) model of surface elasticity. A polymeric brush consists of an system of almost aligned rigid polymeric chains. The interaction between chain links are described through Stockmayer potential, which take into account also dipole-dipole interactions. The presented 2D model can be treated...
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On rotational instability within the nonlinear six-parameter shell theory
PublicationWithin the six-parameter nonlinear shell theory we analyzed the in-plane rotational instability which oc- curs under in-plane tensile loading. For plane deformations the considered shell model coincides up to notations with the geometrically nonlinear Cosserat continuum under plane stress conditions. So we con- sidered here both large translations and rotations. The constitutive relations contain some additional mi- cropolar parameters...