28 resultados para Wiener-Hopf equations.
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Der Beitrag untersucht anhand der Rezeption von zwei exemplarischen Don Karlos-Inszenierungen, die beide in politisch markanten Jahren der österreichischen Geschichte ihre Premiere erlebten, die Funktionalisierung der Institution Burgtheater in Verbindung mit der Funktionalisierung des Dramatikers Friedrich Schiller für eben diese Institution. Eine Neueinstudierung erfolgte 1938, dem Jahr von Österreichs ‚Anschluss’ an Nazi-Deutschland, die andere 1955, dem Jahr der Unterzeichnung des Österreichischen Staatsvertrages. Beide Don Karlos-Inszenierungen fanden als spezifische Festvorstellungen im Rahmen von Feierlichkeiten rund um die Institution Burgtheater statt. Diente 1938 Schillers Don Karlos dazu, als ‚Schlüsselstück’ der ‚nationalsozialistischen Revolution’ einen politisch-gesellschaftlichen Aufbruch zu markieren, so wurde 1955 die Inszenierung des Dramas zum Triumph einer Schauspielerelite, deren Können sich in die konstruierte Tradition eines k.k. ‚Schauspieleradels’ einreihte. Während 1938 der ‚nationale Dichter’ dem ‚heimgekehrten’ Nationaltheater zum ästhetischen ‚Anschluss’ verhalf, diente der ‚überzeitliche’ Klassiker 1955 dazu, eine ästhetische ‚Wiedergeburt’ zu behaupten, die dem restaurativen Kunst- und Kulturbegriff Nachkriegsösterreichs verpflichtet war.
Resumo:
OBJECTIVES: The aim of this study was to determine whether the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI)- or Cockcroft-Gault (CG)-based estimated glomerular filtration rates (eGFRs) performs better in the cohort setting for predicting moderate/advanced chronic kidney disease (CKD) or end-stage renal disease (ESRD). METHODS: A total of 9521 persons in the EuroSIDA study contributed 133 873 eGFRs. Poisson regression was used to model the incidence of moderate and advanced CKD (confirmed eGFR < 60 and < 30 mL/min/1.73 m(2) , respectively) or ESRD (fatal/nonfatal) using CG and CKD-EPI eGFRs. RESULTS: Of 133 873 eGFR values, the ratio of CG to CKD-EPI was ≥ 1.1 in 22 092 (16.5%) and the difference between them (CG minus CKD-EPI) was ≥ 10 mL/min/1.73 m(2) in 20 867 (15.6%). Differences between CKD-EPI and CG were much greater when CG was not standardized for body surface area (BSA). A total of 403 persons developed moderate CKD using CG [incidence 8.9/1000 person-years of follow-up (PYFU); 95% confidence interval (CI) 8.0-9.8] and 364 using CKD-EPI (incidence 7.3/1000 PYFU; 95% CI 6.5-8.0). CG-derived eGFRs were equal to CKD-EPI-derived eGFRs at predicting ESRD (n = 36) and death (n = 565), as measured by the Akaike information criterion. CG-based moderate and advanced CKDs were associated with ESRD [adjusted incidence rate ratio (aIRR) 7.17; 95% CI 2.65-19.36 and aIRR 23.46; 95% CI 8.54-64.48, respectively], as were CKD-EPI-based moderate and advanced CKDs (aIRR 12.41; 95% CI 4.74-32.51 and aIRR 12.44; 95% CI 4.83-32.03, respectively). CONCLUSIONS: Differences between eGFRs using CG adjusted for BSA or CKD-EPI were modest. In the absence of a gold standard, the two formulae predicted clinical outcomes with equal precision and can be used to estimate GFR in HIV-positive persons.
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In this paper we develop a new method to determine the essential spectrum of coupled systems of singular differential equations. Applications to problems from magnetohydrodynamics and astrophysics are given.
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In this talk, we present a coupled system of integral equations for the πN → πN (s-channel) and ππ → N̅N (t-channel) lowest partial waves, derived from Roy–Steiner equations for pion–nucleon scattering. After giving a brief overview of this system of equations, we present the solution of the t-channel sub-problem by means of Muskhelishvili–Omnès techniques, and solve the s-channel sub-problem after finding a set of phase shifts and subthreshold parameters which satisfy the Roy–Steiner equations.
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An operator Riccati equation from systems theory is considered in the case that all entries of the associated Hamiltonian are unbounded. Using a certain dichotomy property of the Hamiltonian and its symmetry with respect to two different indefinite inner products, we prove the existence of nonnegative and nonpositive solutions of the Riccati equation. Moreover, conditions for the boundedness and uniqueness of these solutions are established.
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We investigate parallel algorithms for the solution of the Navier–Stokes equations in space-time. For periodic solutions, the discretized problem can be written as a large non-linear system of equations. This system of equations is solved by a Newton iteration. The Newton correction is computed using a preconditioned GMRES solver. The parallel performance of the algorithm is illustrated.
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In this paper we develop an adaptive procedure for the numerical solution of general, semilinear elliptic problems with possible singular perturbations. Our approach combines both prediction-type adaptive Newton methods and a linear adaptive finite element discretization (based on a robust a posteriori error analysis), thereby leading to a fully adaptive Newton–Galerkin scheme. Numerical experiments underline the robustness and reliability of the proposed approach for various examples