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Search results for: ROUGH SET THEORY
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Cooperative control in production and logistics
PublicationClassical applications of control engineering and information and communication technology (ICT) in production and logistics are often done in a rigid, centralized and hierarchical way. These inflexible approaches are typically not able to cope with the complexities of the manufacturing environment, such as the instabilities, uncertainties and abrupt changes caused by internal and external disturbances, or a large number and variety...
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Corporate social responsibility and forward default risk mediated by financial performance and goodwill
PublicationIn today’s business environment, corporate social responsibility (CSR) has become an increasingly significant factor for firms. This study is driven by the motivation to add to the current literature by investigating the mediating elements that explain the relationship between CSR and forward default risk. In this paper, we attempt to identify the important mediators and give a more comprehensive explanation of this connection...
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The energy concept of money
PublicationPurpose: This paper aims to provide the literature review seeking an answer whether energy can be used as a universal equivalent instead of money. Methodology: The author conducted a review of available literature and data sources related to the money theory and energy concept of money. Findings: It was found that the definition of energy as a general equivalent has a contextual and dynamic nature, and this field’s consolidation...
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Rethinking non-governmental organizations – at the crossroad of economics and civil society
PublicationThe article aims to close the existing knowledge gaps, show why non‑governmental organizations are founded and maintained, and elaborate and systematize the existing knowledge through an analysis of the existing subdisciplines within economics, laying the groundwork for the economics of non‑governmental organizations. The article was written based on a structured literature review with an approach similar to the grounded theory...
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Limiting distribution of the three-state semi-Markov model of technical state transitions of ship power plant machines and its applicability in operational decision-making.
PublicationThe article presents the three-state semi-Markov model of the process {W(t): t 0} of state transitions of a ship power plant machine, with the following interpretation of these states: s1 – state of full serviceability, s2 – state of partial serviceability, and s3 – state of unserviceability. These states are precisely defined for the ship main engine (ME). A hypothesis is proposed which explains the possibility of application...
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Generalization of Kramers-Krönig relations for evaluation of causality in power-law media
PublicationClassical Kramers-Krönig (K–K) relations connect real and imaginary parts of the frequency-domain response of a system. The K–K relations also hold between the logarithm of modulus and the argument of the response, e.g. between the attenuation and the phase shift of a solution to a wave-propagation problem. For square-integrable functions of frequency, the satisfaction of classical K–K relations implies causality in the time domain....
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Quadratic stochastic operators on Banach lattices
PublicationWe study the convergence of iterates of quadratic stochastic operators that are mean monotonic. They are defined on the convex set of probability measures concentrated on a weakly compact order interval S = [0, f] of a fixed Banach lattice F. We study their regularity and identify the limits of trajectories either as the “infimum” or “supremum” of the support of initial distributions.
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CLICK 'n' Sleep: Light-Switch Behavior of Triazole-Containing Tris(bipyridyl)ruthenium Complexes
PublicationA set of RuII complexes incorporating triazole subunits are presented. They show a solvent-dependent light-switch effect. Theoretical calculations revealed the excited states involved in the emission process. The findings are highly important for future design of light-switch sensors and suggest a severe restriction for functional photomolecular devices synthesized by CLICK chemistry.
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REMONTY I PRZEBUDOWY DACHÓW Z ZASTOSOWANIEM ELEMENTÓW LEKKIEJ OBUDOWY
PublicationW artykule przedstawiono przykładowe rozwiązania remontów i przebudowy dachów. Omówiono rozwiązania zmiany materiału pokrycia zarówno bez dodawania warstwy izolacyjnej, jak i z ułożeniem dodatkowej warstwy ocieplenia na istniejącej połaci dachowej a także sposób przebudowy dachu, polegający na ustawianiu nowej, lekkiej konstrukcji nośnej dachu, bezpośrednio na istniejącym pokryciu dachu płaskiego.
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Phase-difference positioning in asynchronous system
PublicationThis paper presents concept and implementation of digital positioning system based on phase difference measurements, designed as a navigational aid for marine applications. Main feature of proposed system is the ability to work in both synchronous mode, with one master station and set of slave stations synchronized with master, and in asynchronous mode with independent clocking of all stations.
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Two-dimensional hydrogen-like atom in a weak magnetic field
PublicationWe consider a non-relativistic two-dimensional (2D) hydrogen-like atom in a weak, static, uniform magnetic field perpendicular to the atomic plane. Within the framework of the Rayleigh-Schr¨odinger perturbation theory, using the Sturmian expansion of the generalized radial Coulomb Green function, we derive explicit analytical expressions for corrections to an arbitrary planar hydrogenic bound-state energy level, up to the fourth...
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Quantum corrections to phi^4 model solutions and applications to Heisenberg chain dynamics
PublicationThe Heisenberg spin chain is considered in φ^4 model approximation. Quantum corrections to classical solutions of the one-dimensional φ^4 model within the correspondent physics are evaluated with account of rest d−1 dimensions of a d-dimensional theory. A quantization of the model is considered in terms of spacetime functional integral. The generalized zeta-function formalism is used to renormalize and evaluate the functional integral...
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Quantum corrections to 4 model solutions and applications to Heisenberg chain dynamics
PublicationThe Heisenberg spin chain is considered in φ^4 model approximation. Quantum corrections to classical solutions of the one-dimensional φ^4 model within the correspondent physics are valuated with account of rest d − 1 dimensions of a d-dimensional theory. A quantization of the model is considered in terms of space- time functional integral. The generalized zeta-function formalism is used to renormalize and evaluate the functional...
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Ab-initio study of electrical and optical properties of allylamine
PublicationThe Density functional theory is one of most promising methodology in fast and accurate calculations of electrical and optical properties from the atomic basis. In this paper, we calculate electrical and optical properties of allylamine (2-propen 1- amine) in terms of accuracy and speed of calculations obtained by selection of DFT-1/2 method with ultrasoft Vanderbilt pseudopotentials. Comparison of density of states between...
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On the material symmetry group for micromorphic media with applications to granular materials
PublicationWithin the framework of the theory of nonlinear elastic micromorphic continua we introduce the new definition of the local material symmetry group. The group consists of ordered triples of second- and third-order tensors describing such changes of a reference placement that cannot be recognized with any experiment. Using the definition we characterize the micromorphic isotropic media, micromorphic fluids, solids and special intermediate...
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Ab-initio study of electrical and optical properties of allylamine
PublicationThe Density functional theory is one of most promising methodology in fast and accurate calculations of electrical and optical properties from the atomic basis. In this paper, we calculate electrical and optical properties of allylamine (2-propen 1- amine) in terms of accuracy and speed of calculations obtained by selection of DFT-1/2 method with ultrasoft Vanderbilt pseudopotentials. Comparison of density of states between molecule...
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FEM simulation of laminate failure in the three point bending
PublicationThe paper presents a FEM simulation of failure of laminate subjected to the three point bending. The numeri-cal model is based on the equivalent single layer approach with 6-paramater non-linear shell theory kinematics. It is implemented in the non-commercial FEM code. The failure initiation is detected with the use of Tsai-Wu criterion. After the failure onset the progressive failure process is modelled through the appropriate...
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Inequivalence of entanglement, steering, and Bell nonlocality for general measurements
PublicationEinstein-Podolsky-Rosen steering is a form of inseparability in quantum theory commonly acknowledged to be intermediate between entanglement and Bell nonlocality. However, this statement has so far only been proven for a restricted class of measurements, namely, projective measurements. Here we prove that entanglement, one-way steering, two-way steering, and nonlocality are genuinely different considering general measurements,...
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Design of horizontal axis wind and water turbines
PublicationThe basic hydrodynamic principles of horizontal axis turbines are presented. Computational methods based on vortex theory for design of such turbines and for calculation of their hydro or aerodynamic characteristics are described in detail. These methods are applicable both to wind and water turbines. The influence of detailed turbine geometry on its characteristics is presented. Several practical computational examples of different...
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Description of the Dataset Hanow – Praecepta de Arte Disputandi – Transcription and Photographs
PublicationThis article briefly characterises the “Hanow – Praecepta de arte disputandi – transcription and photographs” research dataset. The dataset was created based on photographs and transcriptions of the manuscript of the Latin lectures on the rules of effective discussion (the title of the manuscript: Praecepta de arte disputandi) by Michael Chris-toph Hanow (1695–1773), professor of Gdańsk Academic Gymnasium. The original document...
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A procedure for elastoplastic hardening function identification.
PublicationThe inverse analysis method for identifying a nonlinear hardening function,which governs a plastic yielding of soil and rock materials in the framework of elastoplastic theory is presented. A concept of two stage finite element based on spatial discretization of computational space and hardening function space is introduced. The proposed inverse analysis can be classified as the output least squares method. The Levenberg Marquard...
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TRAVELLING WAVES FOR LOW–GRADE GLIOMA GROWTH AND RESPONSE TO A CHEMOTHERAPY MODEL
PublicationLow-grade gliomas (LGGs) are primary brain tumours which evolve very slowly in time, but inevitably cause patient death. In this paper, we consider a PDE version of the previously proposed ODE model that describes the changes in the densities of functionally alive LGGs cells and cells that are irreversibly damaged by chemotherapy treatment. Besides the basic mathematical properties of the model, we study the possibility of the...
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Antiferromagnetic Order in the Rare-Earth Halide Perovskites CsEuBr3 and CsEuCl3
PublicationBulk CsEuBr3 and CsEuCl3 are experimentally shown to be magnetic semiconductors that order antiferromagnetically at Néel temperatures of 2.0 K and 1.0 K, respectively. Given that nanoparticles and thin films of CsEuCl3 have been reported to order ferromagnetically at a similar temperature, our observation of antiferromagnetic ordering in CsEuBr3 and CsEuCl3 expands the possible applications of halide perovskites to now include...
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Observation on red blood cells fluctuations by diffraction phase microscopy
PublicationNowadays there is quite huge need for more and more precise and effective fast diagnostics methods in hematology diseases. One of the most important blood components are erythrocytes – Red Blood Cells (RBCs). Due to their size they are easy to observe using microscopy. It is commonly known that the shape and lifetime of RBCs allows for early disease identification. Authors present special measurement system for RBCs fluctuations...
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Progress on Roman and Weakly Connected Roman Graphs
PublicationA graph G for which γR(G)=2γ(G) is the Roman graph, and if γwcR(G)=2γwc(G), then G is the weakly connected Roman graph. In this paper, we show that the decision problem of whether a bipartite graph is Roman is a co-NP-hard problem. Next, we prove similar results for weakly connected Roman graphs. We also study Roman trees improving the result of M.A. Henning’s A characterization of Roman trees, Discuss. Math. Graph Theory 22 (2002)....
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Experimental ORC micro-power plant for CHP application Part A: power plant arrangement
PublicationThe co-generative micro-power plant with the HFE7100 applied as a working medium was designed and built for experimental investigations. The heat output of the plant was assumed equal to 20 kW, while the electric output amounted to about 3kW. Examples of the results of the preliminary experimental research on a boiler, heat exchangers, a pump and a turbine-generator set are presented and analysed.
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A Study on Influence of Normalization Methods on Music Genre Classification Results Employing kNN Algorithms
PublicationThis paper presents a comparison of different normalization methods applied to the set of feature vectors of music pieces. Test results show the influence of min-nlax and Zero-Mean normalization methods, employing different distance functions (Euclidean, Manhattan, Chebyshev, Minkowski) as a pre-processing for genre classification, on k-Nearest Neighbor (kNN) algorithm classification results.
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Possibilities of applying standard tools of promotion in place marketing
PublicationThe purpose of this article is to present the tools of promotion that can be used by local government units in the developing and implementing of marketing strategies. The article evaluates a set of four basic tools of promotion comprising advertising, public relations and publicity, sales promotion and personal selling. This group was supplemented by direct marketing, presented from the point of view of communication via the Internet.
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UKŁAD PRZENIESIENIA NAPĘDU TURBINY WIATROWEJ
PublicationIn a most commonly met design of a wind turbine the power is transmitted from the rotor to the generator through the system composed of the main shaft, friction connection, multiplicating gearbox and a flexible coupling. The driving system comprises almost a complete set of the machine elements being described during machine design lectures and can serve as an interesting illustration of the lectures.
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Survival time prognosis under a Markov model of cancer development
PublicationIn this study we look at a breast cancer data set of women from Pomerania region collected in year 1987-1992 in the Medical University of Gdańsk. We analyze the clinical risk factors in conjunction with Markov model of cancer development. We evaluate Artificial Neural Network (ANN) survival time prediction via a simulation study.
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Drivetrain of a Wind Turbine
PublicationIn a most commonly met design of a wind turbine the power is transmitted from the rotor to the generator through the system composed of the main shaft, friction connection, multiplying gearbox and a flexible coupling. The driving system comprises almost a complete set of the machine elements being described during machine design lectures and can serve as an interesting illustration...
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Analiza właściwości rozszerzonego obserwatora prędkości maszyny indukcyjnej
PublicationRozszerzony obserwator prędkości został zaproponowany przez prof. Krzemińskiego i jest oparty na rozszerzonym modelu maszyny indukcyjnej, gdzie wprowadzona został nowa zmienna ζ. Jest to nowe podejście do estymacji zmiennych stanu maszyny indukcyjnej i nie wszystkie problemy zostały do tej pory rozwiązane. Zaproponowano wykorzystanie algorytmów ewolucyjnych do doboru wzmocnień obserwatora. W celu redukcji nakładów obliczeniowych...
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Shaping Place Identity through Interaction on the Example of the European Solidarity Centre in Gdansk
PublicationThe article presents process of shaping place identity on the example of an important for Pomerania region investment - European Solidarity Centre. The realization of the European Solidarity Centre aims to be one of the essential elements of shaping Gdańsk’s identity of space. The article is an attempt to analyse how the presence of realization gradually affects the formation of the place identity of new urban space. Analysis...
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Parametrized Local Reduced-Order Models With Compressed Projection Basis for Fast Parameter-Dependent Finite-Element Analysis
PublicationThis paper proposes an automated parametric local model-order reduction scheme for the expedited design of microwave devices using the full-wave finite-element method (FEM). The approach proposed here results in parameterized reduced-order models (ROMs) that account for the geometry and material variation in the selected subregion of the structure. In each subregion, a parameter-dependent projection basis is generated by concatenating...
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Dimensional Synthesis of Coupled-Resonator Pseudoelliptic Microwave Bandpass Filters with Constant and Dispersive Couplings
PublicationIn this paper, we propose a novel technique for the dimensional synthesis of coupled-resonator pseudoelliptic microwave filters with constant and dispersive couplings. The proposed technique is based on numerical simulations of small structures, involving up to two adjacent resonators, and it accounts for a loading effect from other resonators by replacing them with terminations coupled through appropriately scaled inverters. The...
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Fixed orbit index for equivariant maps
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Combinatorial scheme of finding minimal number of periodic points for smooth self-maps of simply connected manifolds
PublicationLet M be a closed smooth connected and simply connected manifold of dimension m at least 3, and let r be a fixed natural number. The topological invariant D^m_r [f], defined by the authors in [Forum Math. 21 (2009), 491-509], is equal to the minimal number of r-periodic points in the smooth homotopy class of f, a given self-map of M. In this paper, we present a general combinatorial scheme of computing D^m_r [f] for arbitrary dimension...
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Connecting orbits for a periodically forced singular planar Newtonian system
PublicationW niniejszym artykule badamy problem istnienia i krotności rozwiązań homoklinicznych i heteroklinicznych dla nieautonomicznych układów Newtonowskich na płaszczyźnie z potencjałem okresowym ze względu na zmienną czasową, mającym maksimum globalne właściwe przyjmowane w dwóch punktach płaszczyzny i punkt osobliwy (studnię nieskończonej głębokości), w otoczeniu którego potencjał spełnia warunek Gordona (gradient potencjału ze względu...
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Edge-Guided Mode Performance and Applications in Nonreciprocal Millimeter-Wave Gyroelectric Components
PublicationThe analogies between the behavior of gyromagnetic and gyroelectric nonreciprocal structures, the use of the simple transfer matrix approach, and the edge-guided (EG) wave property, supported in a parallel plate model for integrated magnetized semiconductor waveguide, are investigated in those frequency regions, where the effective permittivity is negative or positive. As with their ferrite counterparts, the leakage of the EG waves...
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Clarke duality for Hamiltonian systems with nonstandard growth
PublicationWe consider the existence of periodic solutions to Hamiltonian systems with growth conditions involving G-function. We introduce the notion of symplectic G-function and provide relation for the growth of Hamiltonian in terms of certain constant CG associated to symplectic G-function G. We discuss an optimality of this constant for some special cases. We also provide applications to the Φ-laplacian type systems.
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Regularized Local Multivariate Reduced-Order Models With Nonaffine Parameter Dependence
PublicationThis paper addresses a singular problem, not yet discussed in the literature, which occurs when parametric reduced-order models are created using a subspace projection approach with multiple concatenated projection bases. We show that this technique may lead to the appearance of localized artifacts in the frequency characteristics of a system, even when the reduced-order projection basis is rich enough to describe the original...
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Efficient Finite Element Analysis of Axially Symmetrical Waveguides and Waveguide Discontinuities
PublicationA combination of the body-of-revolution and finite element methods is adopted for full-wave analysis of waveguides and waveguide discontinuities involving angular field variation. Such an approach is highly efficient and much more flexible than analytical techniques. The method is performed in two different cases: utilizing a generalized impedance matrix to determine the scattering parameters of a single waveguide section and utilizing...
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A Mesh Deformation Technique Based on Solid Mechanics for Parametric Analysis of High-Frequency Devices With 3-D FEM
PublicationIn this paper, a versatile technique for mesh defor- mation is discussed, targeted at the electromagnetic (EM) field simulation of high-frequency devices using the 3-D finite element method (FEM). The approach proposed applies a linear elasticity model to compute the displacements of the internal mesh nodes in 3-D when the structure geometry is changed. The technique is compared with an alternative approach...
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Rapid Simulation-Driven Multiobjective Design Optimization of Decomposable Compact Microwave Passives
PublicationIn this paper, a methodology for fast multiobjective optimization of the miniaturized microwave passives has been presented. Our approach is applicable to circuits that can be decomposed into individual cells [e.g., compact microstrip resonant cells (CMRCs)]. The structures are individually modeled using their corresponding equivalent circuits and aligned with their accurate, EM simulated...
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Rapid Microwave Design Optimization in Frequency Domain Using Adaptive Response Scaling
PublicationIn this paper, a novel methodology for cost-efficient microwave design optimization in the frequency domain is proposed. Our technique, referred to as adaptive response scaling (ARS), has been developed for constructing a fast replacement model (surrogate) of the high-fidelity electromagnetic-simulated model of the microwave structure under design using its equivalent circuit (low-fidelity model). The basic principle of ARS is...
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Reliable Microwave Modeling By Means of Variable-Fidelity Response Features
PublicationIn this work, methodologies for low-cost and reliable microwave modeling are presented using variable-fidelity response features. The two key components of our approach are: (i) a realization of the modeling process at the level of suitably selected feature points of the responses (e.g., S-parameters vs. frequency) of the structure at hand, and (ii) the exploitation of variable-fidelity EM simulation data, also for the response...
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Two families of infinitely many homoclinics for singular strong force Hamiltonian systems
PublicationWe are concerned with a planar autonomous Hamiltonian system with a potential possessing a single well of infinite depth at a point X and a unique strict global maximum 0 at a point A. Under a strong force condition around the singularity X, via minimization of an action integral and using a shadowing chain lemma together with simple geometrical arguments, we prove the existence of infinitely many geometrically distinct homoclinic...
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Fourier transform symmetry and invariance for neurocontrol of NARMA models
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Equivariant Conley index in Hilbert spaces and applications to strongly indefinite problems
PublicationW pracy zdefiniowano teorię indeksu Conley`a w przestrzeni Hilberta z działaniem zwartej grupy Liego. Została ona wykorzystana do szacowania z dołu ilości rozwiązań periodycznych w teorii nieliniowych autonomicznych układów Hamiltona.
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Numerical conditioning of delta-domain Lyapunov and Riccati equations
PublicationW pracy rozważono problem uwarunkowania dyskretno czasowych równań Lapunowa oraz równań Riccatiego - to znaczy problem wrażliwości rozwiązań takich równań na odchyłki ich parametrów od nominalnych wartości. Zdefiniowano odpowiedni "różniczkowy" wskaźnik uwarunkowania oraz podano efektywną metodę szacowania jego wartości. Udowodniono teoretycznie - a także przekonująco zilustrowano na drodze numerycznej - twierdzenie głoszące, iż...