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Journal of Marine Science and Engineering, 2023 In this paper, the formation coordination control of discrete-time distributed leaderless multiple autonomous underwater vehicle (AUV) system with double independent position–velocity communication topology and control inputs on a nonconvex set is ...
Zheping Yan +4 more
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Vestnik Samarskogo Gosudarstvennogo Tehničeskogo Universiteta. Seriâ: Fiziko-Matematičeskie Nauki, 2020 The paper considers the existence of solutions of the Dirichlet problem for nonlinear elliptic equations of the second order in unbounded domains. Restrictions on the structure of quasilinear equations are formulated in terms of a special class of convex
Larisa Mikhailovna Kozhevnikova +1 more
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Mathematics, 2022 As is well-known, unlike the one-dimensional case, there exist nonnegative polynomials in several real variables that are not sums of squares. First, we briefly review a method of approximating any real-valued nonnegative continuous compactly supported ...
Octav Olteanu
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Boundary operators in effective string theory
Journal of High Energy Physics, 2017 Various universal features of relativistic rotating strings depend on the organization of allowed local operators on the worldsheet. In this paper, we study the set of Neumann boundary operators in effective string theory, which are relevant for the ...
Simeon Hellerman, Ian Swanson
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Convergence of generalized eigenfunction expansions
Electronic Journal of Differential Equations, 2007 We present a simplified theory of generalized eigenfunction expansions for a commuting family of bounded operators and with finitely many unbounded operators.
Mayumi Sakata
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An Exterior Neumann Boundary-Value Problem for the Div-Curl System and Applications
Mathematics, 2021 We investigate a generalization of the equation curlw→=g→ to an arbitrary number n of dimensions, which is based on the well-known Moisil–Teodorescu differential operator.
Briceyda B. Delgado +1 more
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SOLUTION APPROXIMATIONS FOR LYAPUNOV TYPE EQUATIONS ASSOCIATED WITH LINEAR STOCHASTIC EQUATIONS WITH UNBOUNDED COEFFICIENTS AND COUNTABLY INFINITE MARKOV JUMPS [PDF]
Fiabilitate şi Durabilitate, 2018 This paper discuses solution properties of the Lyapunov-type equations (LEs), associated with a class of linear stochastic equations with unbounded coefficients and countably infinite Markov jumps.
Iuliana Carmen BĂRBĂCIORU +1 more
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An integral operator inequality with applications
Journal of Inequalities and Applications, 1999 Linear integral operators are defined acting in the Lebesgue integration spaces on intervals of the real line. A necessary and sufficient condition is given for these operators to be bounded, and a characterisation is given for the operator bounds ...
Everitt WN, Littlejohn LL, Chisholm RS
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Strong Metrizability for Closed Operators and the Semi-Fredholm Operators between Two Hilbert Spaces
International Journal of Analysis and Applications, 2015 To be able to refine the completion of C(H1, H2), the of set all closed densely defined linear operators between two Hilbert spaces H1 and H2, we define in this paper some new strictly stronger metrics than the gap metric g and we characterize the ...
Mohammed Benharrat, Bekkai Messirdi
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Spectral order on unbounded operators and their symmetries
Учёные записки Казанского университета: Серия Физико-математические науки, 2018 The spectral order on positive unbounded operators affiliated with von Neumann algebras have been considered. The spectral order has physical meaning of comparing distribution functions of quantum observables and organizes the structure of unbounded ...
J. Hamhalter, E.A. Turilova
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