Journal articles: 'Partiti Partiti Schweiz'

1

Migliorati, Giovanni, and Alfio Quarteroni. "Multilevel Schwarz methods for elliptic partial differential equations." Computer Methods in Applied Mechanics and Engineering 200, no. 25-28 (June 2011): 2282–96. http://dx.doi.org/10.1016/j.cma.2011.03.017.

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Levi, Decio, and Miguel A. Rodriguez. "ON THE CONSTRUCTION OF PARTIAL DIFFERENCE SCHEMES II: DISCRETE VARIABLES AND SCHWARZIAN LATTICES." Acta Polytechnica 56, no. 3 (June 30, 2016): 236. http://dx.doi.org/10.14311/ap.2016.56.0236.

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In the process of constructing invariant difference schemes which approximate partial differential equations we write down a procedure for discretizing a partial differential equation on an arbitrary lattice. An open problem is the meaning of a lattice which does not satisfy the Clairaut–Schwarz–Young theorem. To analyze it we apply the procedure on a simple example, the potential Burgers equation with two different lattices, an orthogonal lattice which is invariant under the symmetries of the equation and satisfies the commutativity of the partial difference operators and an exponential lattice which is not invariant and does not satisfy the Clairaut–Schwarz–Young theorem. A discussion on the numerical results is presented showing the different behavior of both schemes for two different exact solutions and their numerical approximations.

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Boulbrachene, Messaoud. "Finite Element Convergence Analysis of a Schwarz Alternating Method for Nonlinear Elliptic PDEs." Sultan Qaboos University Journal for Science [SQUJS] 24, no. 2 (January 19, 2020): 109. http://dx.doi.org/10.24200/squjs.vol24iss2pp109-121.

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In this paper, we prove uniform convergence of the standard finite element method for a Schwarz alternating procedure for nonlinear elliptic partial differential equations in the context of linear subdomain problems and nonmatching grids. The method stands on the combination of the convergence of linear Schwarz sequences with standard finite element L-error estimate for linear problems.

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Rudolph, Gerhard. "Erinnerung an Paul Bert (1833—1886) und die Entwicklung der Höhenphysiologie in der Schweiz." Gesnerus 50, no. 1-2 (November 25, 1993): 79–95. http://dx.doi.org/10.1163/22977953-0500102007.

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It is the merit of Paul Bert to have assigned as an important task to experimental physiology the investigation of mountain sickness, of immediate accommodation of the organism to high altitude, and of its long-term acclimatation. In his “Pression Barométrique” of1878, he established the foundations of high-altitude physiology. In particular, he formulated the «law of partial pressure», the partial pressure of the atmospheric gases alone being responsible for their action on the organism, Paul Bert’s historic role, for a long time nearly forgotten, has been recalled to memory by the Swiss medical historians E. H. Ackerknecht and N.Mani. Bert’s line of investigation has been followed especially by Angelo Mosso of Turin and, more recently, by F. Verzár, A. von Muralt, A. Fleisch and other Swiss physiologists.

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Nagid, Nabila, and Hassan Belhadj. "New approach for accelerating the nonlinear Schwarz iterations." Boletim da Sociedade Paranaense de Matemática 38, no. 4 (March 10, 2019): 51–69. http://dx.doi.org/10.5269/bspm.v38i4.37018.

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The vector Epsilon algorithm is an effective extrapolation method used for accelerating the convergence of vector sequences. In this paper, this method is used to accelerate the convergence of Schwarz iterative methods for stationary linear and nonlinear partial differential equations (PDEs). The vector Epsilon algorithm is applied to the vector sequences produced by additive Schwarz (AS) or restricted additive Schwarz (RAS) methods after discretization. Some convergence analysis is presented, and several test-cases of analytical problems are performed in order to illustrate the interest of such algorithm. The obtained results show that the proposed algorithm yields much faster convergence than the classical Schwarz iterations.

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Haynes, Ronald D., and Alexander J. M. Howse. "Alternating Schwarz methods for partial differential equation-based mesh generation." International Journal of Computer Mathematics 92, no. 2 (April 9, 2014): 349–76. http://dx.doi.org/10.1080/00207160.2014.891733.

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Aksoy, Ü., and A. O. çelebi. "Schwarz problem for higher-order complex elliptic partial differential equations." Integral Transforms and Special Functions 19, no. 6 (June 2008): 413–28. http://dx.doi.org/10.1080/10652460801933645.

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8

Cheung, Leung-Fu, and Pui-Fai Leung. "A Schwarz lemma for complete Riemannian manifolds." Bulletin of the Australian Mathematical Society 55, no. 3 (June 1997): 513–15. http://dx.doi.org/10.1017/s000497270003416x.

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We prove a Schwarz Lemma for conformal mappings between two complete Riemannian manifolds when the domain manifold has Ricci curvature bounded below in terms of its distance function. This gives a partial result to a conjecture of Chua.

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McMaster, T. B. M. "A non-causal triangle function." Mathematical Proceedings of the Cambridge Philosophical Society 101, no. 2 (March 1987): 287–90. http://dx.doi.org/10.1017/s0305004100066652.

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Schweizer and Sklar, in their book Probabilistic Metric Spaces, raise the question of whether every triangle function is causal. This note provides a negative answer, by observing certain properties of a suitable partial quaternary operation on the unit interval.

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Ceci, Claudia, Alessandra Cretarola, and Francesco Russo. "GKW representation theorem under restricted information: An application to risk-minimization." Stochastics and Dynamics 14, no. 02 (March 24, 2014): 1350019. http://dx.doi.org/10.1142/s0219493713500196.

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We provide Galtchouk–Kunita–Watanabe representation results in the case where there are restrictions on the available information. This allows one to prove the existence and uniqueness of solution for special equations driven by a general square integrable càdlàg martingale under partial information. Furthermore, we discuss an application to risk-minimization where we extend the results of Föllmer and Sondermann, Hedging of non-redundant contingent claims, to the partial information framework and we show how our result fits in the approach of Schweizer, Risk-minimizing hedging strategies under restricted information.

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11

Wang, Jianfei. "Schwarz-Pick Estimates for Holomorphic Mappings with Values in Homogeneous Ball." Abstract and Applied Analysis 2012 (2012): 1–9. http://dx.doi.org/10.1155/2012/647972.

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LetBXbe the unit ball in a complex Banach spaceX. AssumeBXis homogeneous. The generalization of the Schwarz-Pick estimates of partial derivatives of arbitrary order is established for holomorphic mappings from the unit ballBntoBXassociated with the Carathéodory metric, which extend the corresponding Chen and Liu, Dai et al. results.

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12

Tomaz, Matheus Araujo. "Indústria cultural, ditadura e outras mumunhas mais." Opiniães, no. 15 (December 27, 2019): 14–33. http://dx.doi.org/10.11606/issn.2525-8133.opiniaes.2019.159361.

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O presente artigo busca analisar como as questões ligadas ao desenvolvimento das forças produtivas em “Baby” (1968) de Caetano Veloso e “Roda Viva” (1967) de Chico Buarque foram formalizadas. Para isso, foram utilizados os escritos de Adorno e Horkheimer sobre a indústria cultural e de Roberto Schwarz sobre seus desdobramentos no Brasil como ponto de partida.

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Li, Ke, Dali Guo, and Yunxiang Zhao. "Convergence Analysis of Schwarz Waveform Relaxation for Nonlocal Diffusion Problems." Mathematical Problems in Engineering 2021 (July 21, 2021): 1–25. http://dx.doi.org/10.1155/2021/5574403.

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Diffusion equations with Riemann–Liouville fractional derivatives are Volterra integro-partial differential equations with weakly singular kernels and present fundamental challenges for numerical computation. In this paper, we make a convergence analysis of the Schwarz waveform relaxation (SWR) algorithms with Robin transmission conditions (TCs) for these problems. We focus on deriving good choice of the parameter involved in the Robin TCs, at the continuous and fully discretized level. Particularly, at the space-time continuous level, we show that the derived Robin parameter is much better than the one predicted by the well-understood equioscillation principle. At the fully discretized level, the problem of determining a good Robin parameter is studied in the convolution quadrature framework, which permits us to precisely capture the effects of different temporal discretization methods on the convergence rate of the SWR algorithms. The results obtained in this paper will be preliminary preparations for our further study of the SWR algorithms for integro-partial differential equations.

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14

Degen, Bernard, and Christian Koller. "Protest und Streiks in der Schweiz in der zweiten Hälfte des Ersten Weltkriegs." Journal of Modern European History 17, no. 1 (February 2019): 64–82. http://dx.doi.org/10.1177/1611894418820257.

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Zusammenfassung Switzerland was spared direct involvement into the First World War, nevertheless the global conflict had tremendous political and economic impact on the neutral republic. Major antagonisms emerged between the different linguistic groups sympathising with opposing belligerent coalitions as well as between different social strata. Food and fuel shortages and wartime inflation as well as a lack of integration of the labour movement into the political system and its partial shift to the left resulted in a wave of strikes and protest in the second half of the war that continued into the first two post-war years. Its culmination was a national general strike in November 1918 lasting for three days upon the war’s conclusion, and that in bourgeois circles was wrongly considered an attempted revolution. Whilst this is considered the most severe crisis in modern Swiss history, from a transnational perspective, it was no more than a relatively mild variation of the worldwide upheavals going on at the time.

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15

Wu, Shu-Lin. "Schwarz waveform relaxation algorithm for heat equations with distributed delay." Thermal Science 20, suppl. 3 (2016): 659–67. http://dx.doi.org/10.2298/tsci16s3659w.

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Heat equations with distributed delay are a class of mathematic models that has wide applications in many fields. Numerical computation plays an important role in the investigation of these equations, because the analytic solutions of partial differential equations with time delay are usually unavailable. On the other hand, duo to the delay property, numerical computation of these equations is time-consuming. To reduce the computation time, we analyze in this paper the Schwarz waveform relaxation algorithm with Robin transmission conditions. The Robin transmission conditions contain a free parameter, which has a significant effect on the convergence rate of the Schwarz waveform relaxation algorithm. Determining the Robin parameter is therefore one of the top-priority matters for the study of the Schwarz waveform relaxation algorithm. We provide new formula to fix the Robin parameter and we show numerically that the new Robin parameter is more efficient than the one proposed previously in the literature.

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16

Yuldashev, Tursun K., and Bakhtiyar J. Kadirkulov. "Inverse Problem for a Partial Differential Equation with Gerasimov–Caputo-Type Operator and Degeneration." Fractal and Fractional 5, no. 2 (June 21, 2021): 58. http://dx.doi.org/10.3390/fractalfract5020058.

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In the three-dimensional open rectangular domain, the problem of the identification of the redefinition function for a partial differential equation with Gerasimov–Caputo-type fractional operator, degeneration, and integral form condition is considered in the case of the 0<α≤1 order. A positive parameter is present in the mixed derivatives. The solution of this fractional differential equation is studied in the class of regular functions. The Fourier series method is used, and a countable system of ordinary fractional differential equations with degeneration is obtained. The presentation for the redefinition function is obtained using a given additional condition. Using the Cauchy–Schwarz inequality and the Bessel inequality, the absolute and uniform convergence of the obtained Fourier series is proven.

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17

de Camargo, André Pierro. "A proof of the Schwarz theorem on mixed partial derivatives via elementary approximation theory." Elemente der Mathematik 75, no. 3 (July 13, 2020): 125–28. http://dx.doi.org/10.4171/em/413.

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18

Aksoy, Ümit, Heinrich Begehr, and A. Okay Çelebi. "Schwarz problem for higher‐order complex partial differential equations in the upper half plane." Mathematische Nachrichten 292, no. 6 (January 4, 2019): 1183–93. http://dx.doi.org/10.1002/mana.201800028.

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19

Levi, Decio, and Miguel A. Rodríguez. "Construction of partial difference schemes: I. The Clairaut, Schwarz, Young theorem on the lattice." Journal of Physics A: Mathematical and Theoretical 46, no. 29 (July 4, 2013): 295203. http://dx.doi.org/10.1088/1751-8113/46/29/295203.

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20

Berenguer, L., and D. Tromeur-Dervout. "Asynchronous partial update of the Restricted Additive Schwarz preconditioner to solve nonlinear CFD problems." Computers & Fluids 110 (March 2015): 211–18. http://dx.doi.org/10.1016/j.compfluid.2014.09.049.

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21

Yang, Danping. "Non-iterative parallel Schwarz algorithms based on overlapping domain decomposition for parabolic partial differential equations." Mathematics of Computation 86, no. 308 (May 11, 2017): 2687–718. http://dx.doi.org/10.1090/mcom/3102.

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22

Rodrigue, Garry. "Some ideas for decomposing the domain of elliptic partial differential equations in the schwarz process." Communications in Applied Numerical Methods 2, no. 3 (May 1986): 245–49. http://dx.doi.org/10.1002/cnm.1630020304.

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23

Xu, Yingxiang, and Xin Chen. "Optimized Schwarz Methods for the Optimal Control of Systems Governed by Elliptic Partial Differential Equations." Journal of Scientific Computing 79, no. 2 (November 28, 2018): 1182–213. http://dx.doi.org/10.1007/s10915-018-0886-4.

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24

Wu, Shu-Lin, and Ting-Zhu Huang. "Schwarz Waveform Relaxation for a Neutral Functional Partial Differential Equation Model of Lossless Coupled Transmission Lines." SIAM Journal on Scientific Computing 35, no. 2 (January 2013): A1161—A1191. http://dx.doi.org/10.1137/110860975.

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25

Ivashkovich, Sergey, and Jean-Pierre Rosay. "Schwarz-type lemmas for solutions of $\bar\partial $-inequalities and complete hyperbolicity of almost complex manifolds." Annales de l’institut Fourier 54, no. 7 (2004): 2387–435. http://dx.doi.org/10.5802/aif.2084.

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26

Delladio, Silvano. "A note on a generalization of the Schwarz theorem about the equality of mixed partial derivatives." Mathematische Nachrichten 290, no. 11-12 (January 3, 2017): 1630–36. http://dx.doi.org/10.1002/mana.201600195.

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27

Corrêa, Ana Laura Dos Reis. "As duas faces das medalhas: dialética aparência e essência em “Teoria do medalhão” e “O emplasto”." O Eixo e a Roda: Revista de Literatura Brasileira 24, no. 2 (December 18, 2015): 31–47. http://dx.doi.org/10.17851/2358-9787.24.2.31-47.

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Tendo como ponto de partida o desejo de notoriedade compartilhado pelos protagonistas de “Teoria do medalhão” e Memórias póstumas de Brás Cubas, este texto procura discutir o caráter realista da obra de Machado de Assis, considerando as dualidades de sua narrativa como uma unidade contraditória de essência e aparência. Buscando pôr em diálogo duas concepções diferentes a respeito do realismo, a de Roberto Schwarz acerca do realismo desolador de Machado e a de György Lukács quanto as possibilidades do realismo no período da decadência ideológica burguesa, este trabalho persegue e apresenta, de forma inicial, as possíveis relações de aproximação entre a tipicidade realista após 1848 e a especificidade nacional.

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Chang, Huibin, and Danping Yang. "A Schwarz domain decomposition method with gradient projection for optimal control governed by elliptic partial differential equations." Journal of Computational and Applied Mathematics 235, no. 17 (July 2011): 5078–94. http://dx.doi.org/10.1016/j.cam.2011.04.037.

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Lapin, Alexander. "Geometric Convergence of Iterative Methods for a Problem with M-matrices and Diagonal Multivalued Operators." Computational Methods in Applied Mathematics 2, no. 1 (2002): 26–40. http://dx.doi.org/10.2478/cmam-2002-0002.

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Abstract A finite-dimensional problem with several M-matrices and diagonal maximal monotone operators is studied. This problem includes variational inequalities with M-matrices as a partial case and appears, in particular, as a mesh approximation for a free boundary problem with several constraints and nonlinear relations. The existence of an unique solution for the problem is studied, as well as the convergence and geometric rate of the convergence for a class of the iterative methods, the Schwarz alternating-type methods among them. The application of the general results to a mesh scheme for a dam problem is considered. Parallel iterative methods are constructed on the basis of the domain decomposition, geometric convergence of these methods is justified.

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PATERA, ANTHONY T., and EINAR M. RØNQUIST. "A GENERAL OUTPUT BOUND RESULT: APPLICATION TO DISCRETIZATION AND ITERATION ERROR ESTIMATION AND CONTROL." Mathematical Models and Methods in Applied Sciences 11, no. 04 (June 2001): 685–712. http://dx.doi.org/10.1142/s0218202501001057.

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We present a general adjoint procedure that, under certain hypotheses, provides inexpensive, rigorous, accurate, and constant-free lower and upper asymptotic bounds for the error in "outputs" which are linear functionals of solutions to linear (e.g. partial-differential or algebraic) equations. We describe two particular instantiations for which the necessary hypotheses can be readily verified. The first case — a re-interpretation of earlier work — assesses the error due to discretization: an implicit Neumann-subproblem finite element a posteriori technique applicable to general elliptic partial differential equations. The second case — new to this paper — assesses the error due to solution, in particular, incomplete iteration: a primal-dual preconditioned conjugate-gradient Lanczos method for symmetric positive-definite linear systems, in which the error bounds for the output serve as stopping criterion; numerical results are presented for additive-Schwarz domain-decomposition-preconditioned solution of a spectral element discretization of the Poisson equation in three space dimensions. In both instantiations, the computational savings are significant: since the error in the output of interest can be precisely quantified, very fine meshes, and extremely small residuals, are no longer required to ensure adequate accuracy; numerical uncertainty, though certainly not eliminated, is greatly reduced.

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Clausen, Jan, Milan Kelch, Franz Josef Wöstmann, and Matthias Busse. "Development of a High Pressure Die Casting Tool for Partial Integration of Glass Fiber Structures." Key Engineering Materials 742 (July 2017): 520–26. http://dx.doi.org/10.4028/www.scientific.net/kem.742.520.

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Due to the growing demand for lightweight solutions in a wide range of industries, the selection and combination of various materials is becoming more and more important. As a result, the need for suitable joining technologies is increasing along with it. Within the DFG research group "Schwarz-Silber" ("black-silver"), Fraunhofer IFAM is investigating so-called transitional structures in cooperation with the University of Bremen. In this process, glass fiber structures are integrated into aluminum by a high pressure die casting process. These structures are used for the electrochemical insulation between aluminum and carbon fiber textiles, which are connected by textile processes in a subsequent production step. A solid hybrid structure is finally achieved through a resin-impregnation process. The key challenges are the positioning, pre-tensioning and infiltration of the glass fiber structures within the high pressure die casting process. In order to meet these challenges, a customized die casting tool was developed within the project. With the aid of mold-filling simulations, the die system of the die casting tool was optimized to achieve better infiltration of the fiber bundles and to additionally support the position of the glass fibers in the casting process. After the design of the molding tool, the implementation was carried out in collaboration with a toolmaker. In subsequent, up-to-date investigations, the positioning and infiltration of different variants of glass fiber structures is evaluated. The results are compared with previous attempts to position and infiltrate the glass fiber structures to assess the effect of the optimized newly designed tool.

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Prysthon, Angela. "Revisitando a Antropofagia: os Estudos Culturais brasileiros nos anos 90." Revista FAMECOS 9, no. 17 (April 10, 2008): 101. http://dx.doi.org/10.15448/1980-3729.2002.17.3155.

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Este ensaio procura situar as correntes principais de apreensão de fenômenos culturais na década de 90: uma, herdeira dos estudos sociológicos de Antonio Candido e da Teoria Crítica praticada por Roberto Schwarz, onde a História entra como peça fundamental e o aporte marxista serve como ponto de partida para uma revisão contemporânea. Uma outra que, utilizando os avanços formalistas e a autoridade científica conferidos por abordagens estruturais, retoma as vozes dos fundadores de uma “semiótica brasileira”, Haroldo de Campos, Augusto de Campos e Décio Pignatari. E a problematização do conceito de entrelugar (elaborado por Silviano Santiago no final dos anos 70) que vai representar uma das saídas mais consistentes para o eterno dilema entre formalismos e sociologismos da cultura brasileira.

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Vion, Alexandre, and Christophe Geuzaine. "Improved sweeping preconditioners for domain decomposition algorithms applied to time-harmonic Helmholtz and Maxwell problems." ESAIM: Proceedings and Surveys 61 (2018): 93–111. http://dx.doi.org/10.1051/proc/201861093.

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Sweeping-type algorithms have recently gained a lot of interest for the solution of highfrequency time-harmonic wave problems, in particular when used in combination with perfectly matched layers. However, an inherent problem with sweeping approaches is the sequential nature of the process, which makes them inadequate for efficient implementation on parallel computers. We propose several improvements to the double-sweep preconditioner originally presented in [18], which uses sweeping as a matrix-free preconditioner for a Schwarz domain decomposition method. Similarly, the improved preconditioners are based on approximations of the inverse of the Schwarz iteration operator: the general methodology is to apply well-known algebraic techniques to the operator seen as a matrix, which in turn is processed to obtain equivalent matrix-free routines that we use as preconditioners. A notable feature of the new variants is the introduction of partial sweeps that can be performed concurrently in order to make a better usage of the resources. As these modifications still leave some unexploited computational power, we also propose to combine them with right-hand side pipelining to further improve parallelism and achieve significant speed-ups. Examples are presented on high-frequency Helmholtz and Maxwell problems, in two and three dimensions, to demonstrate the properties of our improvements on parallel computer architectures.

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Wu, Yuqi, and Xiao-Chuan Cai. "A Parallel Domain Decomposition Algorithm for Simulating Blood Flow with Incompressible Navier-Stokes Equations with Resistive Boundary Condition." Communications in Computational Physics 11, no. 4 (April 2012): 1279–99. http://dx.doi.org/10.4208/cicp.060510.150511s.

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AbstractWe introduce and study a parallel domain decomposition algorithm for the simulation of blood flow in compliant arteries using a fully-coupled system of nonlinear partial differential equations consisting of a linear elasticity equation and the incompressible Navier-Stokes equations with a resistive outflow boundary condition. The system is discretized with a finite element method on unstructured moving meshes and solved by a Newton-Krylov algorithm preconditioned with an overlapping restricted additive Schwarz method. The resistive outflow boundary condition plays an interesting role in the accuracy of the blood flow simulation and we provide a numerical comparison of its accuracy with the standard pressure type boundary condition. We also discuss the parallel performance of the implicit domain decomposition method for solving the fully coupled nonlinear system on a supercomputer with a few hundred processors.

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Kumar, Sunil, and B. V. Rathish Kumar. "A Finite Element Domain Decomposition Approximation for a Semilinear Parabolic Singularly Perturbed Differential Equation." International Journal of Nonlinear Sciences and Numerical Simulation 18, no. 1 (February 1, 2017): 41–55. http://dx.doi.org/10.1515/ijnsns-2015-0156.

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AbstractIn this paper, we propose a Monotone Schwarz Iterative Method (MSIM) under the framework of Domain Decomposition Strategy for solving semilinear parabolic singularly perturbed partial differential equations (SPPDEs). A three-step Taylor Galerkin Finite Element (3TGFE) approximation of semilinear parabolic SPPDE is carried out during each of the stages of the MSIM. Appropriate Interface Problems are introduced to update the subdomain boundary conditions in the Monotone Iterative Domain Decomposition (MIDD) method. The convergence of the MIDD method has been established. In addition, the stability and $\epsilon$-uniform convergence of 3TGFE based MIDD has been discussed. Further, by using maximum principle and induction hypothesis, the convergence of the proposed MSIM has been established. Also, the proposed 3TGFE based MIDD has been successfully implemented on a couple of test problems.

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Shaoyu, Dai, and Chen Huaihui. "Schwarz-Pick estimates for partial derivatives of arbitary order of bounded holomorphic functions in the unit ball of ℂn." Acta Mathematica Scientia 31, no. 4 (July 2011): 1624–32. http://dx.doi.org/10.1016/s0252-9602(11)60348-2.

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Rahbar, Farhad, Mostafa Sargolzaei, Faramarz Khalighi, and Mohammad Roshanro. "Measuring the Productivity of Capital in the Industrial Sector of Sistan and Baloochestan State, Iran." International Letters of Social and Humanistic Sciences 61 (October 2015): 138–44. http://dx.doi.org/10.18052/www.scipress.com/ilshs.61.138.

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This working paper strives to measure analyze and the productivity of capital in the industrial sector in the case of the State of Sistan and Baloochestan over the period 1982-2009. Three production functions (Debertin, Cobb-Douglas and Transcendental logarithm (Translog)) are estimated by relevant variables such as labor, capital and GDP. Akaike, Schwarz information criteria and LR test indicate that the Cobb-Douglas model should be preferred. In order to avoid a spurious regressing Johansen test detects a cointegration. According to this detection the cointegration term (-0.46) indicates that the deviation from long-run equilibrium is rectified gradually through a series of partial short term adjustments after or so two years.The results of this function reveal that there's been a diminishing trend in productivity of capital since 1982.So it demonstrates the lack of attention to capital productivity. Thus we can conclude that Sistan suffers from the absence of comprehensive strategy and segregation between trade and production policies.

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Nadeem, S. A., and P. K. Jimack. "Parallel implementation of an optimal two level additive Schwarz preconditioner for the 3-D finite element solution of elliptic partial differential equations." International Journal for Numerical Methods in Fluids 40, no. 12 (2002): 1571–79. http://dx.doi.org/10.1002/fld.413.

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Bowers, Philip L. "The upper Perron method for labelled complexes with applications to circle packings." Mathematical Proceedings of the Cambridge Philosophical Society 114, no. 2 (September 1993): 321–45. http://dx.doi.org/10.1017/s0305004100071619.

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The construction of geometric surfaces via labelled complexes was introduced by Thurston[16, chapter 13], and subsequent applications and developments have appeared in [1, 3, 4, 5, 14, 15]. The basic idea of using labelled complexes to produce geometric structures is that the vertices of a simplicial triangulation of a surface can be labelled with positive real numbers that collectively determine a metric of constant curvature ±1 or 0, with possible singularities at vertices, by using the label values to identify 2-simplices of the triangulation with geometric triangles. Beardon and Stephenson[1] developed a particularly simple method for producing non-singular surfaces via labelled complexes that is modelled after the classical Perron method for producing harmonic functions, and they applied their method in [2] to construct a fairly comprehensive theory of circle packings in general Riemann surfaces. This Perron method was developed more fully by Stephenson and the author in [3, 4] and applied to the study of circle packing points in moduli space. At about the same time and independently of Beardon, Stephenson, and Bowers, Carter and Rodin [5] and Doyle [8] developed the method for flat surfaces and Minda and Rodin [14] developed the method for finite type surfaces. Minda and Rodin [14] applied their development to give partial solutions to the labelled complex version of the classical Schwarz-Picard problem that concerns the construction of singular hyperbolic metrics on surfaces with prescribed singularities. In this paper, we modify the aforementioned approaches and examine the upper Perron method for producing non-singular geometric surfaces. This upper method has several advantages over the Perron method as developed previously and provides a complete solution to the labelled complex version of the Schwarz-Picard problem.

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Santo, Niccolò Dal, Simone Deparis, and Andrea Manzoni. "A numerical investigation of multi space reduced basis preconditioners for parametrized elliptic advection-diffusion equations." Communications in Applied and Industrial Mathematics 8, no. 1 (December 20, 2017): 282–97. http://dx.doi.org/10.1515/caim-2017-0015.

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AbstractWe analyze the numerical performance of a preconditioning technique recently proposed in [1] for the efficient solution of parametrized linear systems arising from the finite element (FE) discretization of parameterdependent elliptic partial differential equations (PDEs). In order to exploit the parametric dependence of the PDE, the proposed preconditioner takes advantage of the reduced basis (RB) method within the preconditioned iterative solver employed to solve the linear system, and combines a RB solver, playing the role of coarse component, with a traditional fine grid (such as Additive Schwarz or block Jacobi) preconditioner. A sequence of RB spaces is required to handle the approximation of the error-residual equation at each step of the iterative method at hand, whence the name of Multi Space Reduced Basis (MSRB) method. In this paper, a numerical investigation of the proposed technique is carried on in the case of a Richardson iterative method, and then extended to the flexible GMRES method, in order to solve parameterized advection-diffusion problems. Particular attention is payed to the impact of anisotropic diffusion coefficients and (possibly dominant) transport terms on the proposed preconditioner, by carrying out detailed comparisons with the current state of the art algebraic multigrid preconditioners.

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Tiwari, Vijay K., Nidhi Rawat, Kumari Neelam, Gursharn S. Randhawa, Kuldeep Singh, Parveen Chhuneja, and Harcharan S. Dhaliwal. "Development of Triticum turgidum subsp. durum – Aegilops longissima amphiploids with high iron and zinc content through unreduced gamete formation in F1 hybrids." Genome 51, no. 9 (September 2008): 757–66. http://dx.doi.org/10.1139/g08-057.

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Four different interspecific hybrids involving three different accessions of Aegilops longissima Schweinf. & Muschl. with high grain iron and zinc content and three Triticum turgidum L. subsp. durum (Desf.) Husn. cultivars with low micronutrient content were made for durum wheat biofortification and investigated for chromosome pairing, fertility, putative amphiploidy, and micronutrient content. The chromosome pairing in the 21-chromosome F1 hybrids (ABSl) consisted of 0–6 rod bivalents and occasionally 1 trivalent. All the F1 hybrids, however, unexpectedly showed partial but variable fertility. The detailed meiotic investigation indicated the simultaneous occurrence of two types of aberrant meiotic divisions, namely first-division restitution and single-division meiosis, leading to regular dyads and unreduced gamete formation and fertility. The F2 seeds, being putative amphiploids (AABBSlSl), had nearly double the chromosome number (40–42) and regular meiosis and fertility. The F1 hybrids were intermediate between the two parents for different morphological traits. The putative amphiploids with bold seed size had higher grain ash content and ash iron and zinc content than durum wheat cultivars, suggesting that Ae. longissima possesses a better genetic system(s) for uptake and seed sequestration of iron and zinc, which could be transferred to elite durum and bread wheat cultivars and exploited.

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Tripathi, Rahul, A. K. Nayak, R. Raja, Mohammad Shahid, Anjani Kumar, Sangita Mohanty, B. B. Panda, B. Lal, and Priyanka Gautam. "Forecasting Rice Productivity and Production of Odisha, India, Using Autoregressive Integrated Moving Average Models." Advances in Agriculture 2014 (2014): 1–9. http://dx.doi.org/10.1155/2014/621313.

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Forecasting of rice area, production, and productivity of Odisha was made from the historical data of 1950-51 to 2008-09 by using univariate autoregressive integrated moving average (ARIMA) models and was compared with the forecasted all Indian data. The autoregressive (p) and moving average (q) parameters were identified based on the significant spikes in the plots of partial autocorrelation function (PACF) and autocorrelation function (ACF) of the different time series. ARIMA (2, 1, 0) model was found suitable for all Indian rice productivity and production, whereas ARIMA (1, 1, 1) was best fitted for forecasting of rice productivity and production in Odisha. Prediction was made for the immediate next three years, that is, 2007-08, 2008-09, and 2009-10, using the best fitted ARIMA models based on minimum value of the selection criterion, that is, Akaike information criteria (AIC) and Schwarz-Bayesian information criteria (SBC). The performances of models were validated by comparing with percentage deviation from the actual values and mean absolute percent error (MAPE), which was found to be 0.61 and 2.99% for the area under rice in Odisha and India, respectively. Similarly for prediction of rice production and productivity in Odisha and India, the MAPE was found to be less than 6%.

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Kong, Fande, and Xiao-Chuan Cai. "Scalability study of an implicit solver for coupled fluid-structure interaction problems on unstructured meshes in 3D." International Journal of High Performance Computing Applications 32, no. 2 (May 4, 2016): 207–19. http://dx.doi.org/10.1177/1094342016646437.

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Fluid-structure interaction (FSI) problems are computationally very challenging. In this paper we consider the monolithic approach for solving the fully coupled FSI problem. Most existing techniques, such as multigrid methods, do not work well for the coupled system since the system consists of elliptic, parabolic and hyperbolic components all together. Other approaches based on direct solvers do not scale to large numbers of processors. In this paper, we introduce a multilevel unstructured mesh Schwarz preconditioned Newton–Krylov method for the implicitly discretized, fully coupled system of partial differential equations consisting of incompressible Navier–Stokes equations for the fluid flows and the linear elasticity equation for the structure. Several meshes are required to make the solution algorithm scalable. This includes a fine mesh to guarantee the solution accuracy, and a few isogeometric coarse meshes to speed up the convergence. Special attention is paid when constructing and partitioning the preconditioning meshes so that the communication cost is minimized when the number of processor cores is large. We show numerically that the proposed algorithm is highly scalable in terms of the number of iterations and the total compute time on a supercomputer with more than 10,000 processor cores for monolithically coupled three-dimensional FSI problems with hundreds of millions of unknowns.

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Yuldashev, T. K., and E. T. Karimov. "Mixed type integro-differential equation with fractional order Caputo operators and spectral parameters." Izvestiya Instituta Matematiki i Informatiki Udmurtskogo Gosudarstvennogo Universiteta 57 (May 2021): 190–205. http://dx.doi.org/10.35634/2226-3594-2021-57-10.

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The issues of unique solvability of a boundary value problem for a mixed type integro-differential equation with two Caputo time-fractional operators and spectral parameters are considered. A mixed type integro-differential equation is a partial integro-differential equation of fractional order in both positive and negative parts of multidimensional rectangular domain under consideration. The fractional Caputo operator's order is less in the positive part of the domain, than the order of Caputo operator in the negative part of the domain. Using the method of Fourier series, two systems of countable systems of ordinary fractional integro-differential equations with degenerate kernels are obtained. Further, a method of degenerate kernels is used. To determine arbitrary integration constants, a system of algebraic equations is obtained. From this system, regular and irregular values of spectral parameters are calculated. The solution of the problem under consideration is obtained in the form of Fourier series. The unique solvability of the problem for regular values of spectral parameters is proved. To prove the convergence of Fourier series, the properties of the Mittag-Leffler function, Cauchy-Schwarz inequality and Bessel inequality are used. The continuous dependence of the problem solution on a small parameter for regular values of spectral parameters is also studied. The results are formulated as a theorem.

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Sousa-Correia, Cristina, Ana Alves, José C. Rodrigues, Suzana Ferreira-Dias, José M. Abreu, Nigel Maxted, Brian Ford-Lloyd, and Manfred Schwanninger. "Oil Content Estimation of Individual Kernels of Quercus Ilex Subsp. Rotundifolia [(Lam) O. Schwarz] Acorns by Fourier Transform near Infrared Spectroscopy and Partial Least Squares Regression." Journal of Near Infrared Spectroscopy 15, no. 4 (August 2007): 247–60. http://dx.doi.org/10.1255/jnirs.733.

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The aim of this work was to use Fourier transform near infrared (FT-NIR) spectroscopy and partial least squares regression (PLSR) to estimate the oil content of individual Holm oak ( Quercus sp.) acorn kernels from different trees, sites and years that should be used in the future for molecular marker association studies. Sampling of acorns in two consecutive years (2003 and 2004) and from different sites in Portugal provided independent sample sets. A total of 89 samples (acorn kernels) representative of the natural oil content range were extracted. The results of the analyses performed by three people revealed accuracy of the oil extraction procedure ( n-hexane) and the precision (repeatability) of this method, assessed during a four-day period, gave a standard deviation of 0.1%. Careful wavenumber selection and several steps of validation of the PLSR models led to a final robust model that allowed the precise prediction of the oil content of individual acorns. By using the wavenumber ranges from 5995 to 5323 cm−1 and from 4478 to 4177 cm−1 of the vector normalised spectra, a PLSR model with a coefficient of determination ( r 2) of 0.992 and a root mean square error of cross-validation ( RMSECV) of 0.37% was achieved. The RPD value of about 10 and a bias of almost zero showed that the developed models are good for process control, development, and applied research. Oil content estimation of individual Quercus sp. acorns by FT-NIR and PLSR was shown to be possible. The varying water content detected in the spectra of the milled kernels after drying in similar conditions, within and especially between years, could be handled.

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Kowal, Robert. "The Efficiency of OLS Estimators of Structural Parameters in a Simple Linear Regression Model in the Calibration of the Averages Scheme." Folia Oeconomica Stetinensia 16, no. 2 (December 1, 2016): 236–49. http://dx.doi.org/10.1515/foli-2016-0037.

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Abstract A simple linear regression model is one of the pillars of classic econometrics. Multiple areas of research function within its scope. One of the many fundamental questions in the model concerns proving the efficiency of the most commonly used OLS estimators and examining their properties. In the literature of the subject one can find taking back to this scope and certain solutions in that regard. Methodically, they are borrowed from the multiple regression model or also from a boundary partial model. Not everything, however, is here complete and consistent. In the paper a completely new scheme is proposed, based on the implementation of the Cauchy-Schwarz inequality in the arrangement of the constraint aggregated from calibrated appropriately secondary constraints of unbiasedness which in a result of choice the appropriate calibrator for each variable directly leads to showing this property. A separate range-is a matter of choice of such a calibrator. These deliberations, on account of the volume and kinds of the calibration, were divided into a few parts. In the one the efficiency of OLS estimators is proven in a mixed scheme of the calibration by averages, that is preliminary, and in the most basic frames of the proposed methodology. In these frames the future outlines and general premises constituting the base of more distant generalizations are being created.

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Kollefrath, Ralf, Marcel Savary, and Jörg Schwela. "An Evaluation of the Fit of Metal-Ceramic Restorations Made with an Autoclaved Silicone-Based Impression Material." Journal of Contemporary Dental Practice 11, no. 4 (2010): 63–70. http://dx.doi.org/10.5005/jcdp-11-4-63.

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Abstract Aim To demonstrate the clinical feasibility of autoclaving certain silicone impression materials in order to avoid potential cross-contamination during handling, transport, and subsequent processing. Background Semicritical devices are recommended to be treated at least with high-level disinfectants or actually steam sterilized at 134°C. To date dental impressions have been disinfected rather than sterilized, so the question remains should they be sterilized before being sent to the dental laboratory? Case Descriptions Two identical impressions per case were made of metal-ceramic crown and fixed partial denture preparations on the same patient using addition type polyvinyl siloxane (PVS) impression materials (AFFINIS, R Coltene/ Whaledent AG, 9450 Altstatten, Switzerland) in different trays. The first impression (IMPx1) was cleaned and treated with an intermediate-level disinfectant (FD 322.Fast Disinfection Spray, Durr Dental, 74321 Bietigheim-Bissingen, Germany). The second impression (IMPx2) was cleaned, treated with an intermediate-level disinfectant as with IMPx1, subjected to a computer tomography (CT) scan with a dimensional resolution of ±10 μm, steam sterilized, and then subjected to a second CT scan. The dimensional changes of the second impression after steam sterilization were calculated by comparing the overlay of the two CT scans and expressed by color coding of the impression graphics. After the second scan, the impression was sent to a dental laboratory to fabricate a metal-ceramic crown or metal-ceramic fixed partial denture restoration to the one produced from the first impression (IMPx1) subjected only to disinfection. This process was repeated for four clinical cases. Conclusion Impressions made with AFFINIS® silicone impression materials in a rigid reinforced polycarbonate impression tray or in a metal dual-arch tray can be autoclaved. The overall dimensional stability of the impressions and the quality of single crowns and small fixed partial dentures made using IMPx2 was not compromised. The maximum dimensional differences at the preparations of the nonautoclaved and the autoclaved impressions were found to be within acceptable limits of about 50–100 ìm. Clinical Significance Steam sterilization of AFFINIS® impressions is possible without adversely affecting dimensional change. In addition, clinicians can clearly indicate to the dental practice and laboratory personnel that sterilization of the impressions has been performed, cross-contamination is unlikely, and the impressions present no apparent health hazard during transport and subsequent processing. Disclosure Dr. Kollefrath is head of Research and Development, Elastomers at Coltène/ Whaledent AG, Altstätten, Switzerland, the manufacturer of the impression material evaluated in this report. Citation Kollefrath R, Savary M, Schwela J. An Evaluation of the Fit of Metal-Ceramic Restorations Made with an Autoclaved Silicone- Based Impression Material. J Contemp Dent Pract [Internet]. 2010 July; 11(4):063-070. Available from: http://www.thejcdp.com/journal/ view/volume11-issue4-kollefrath

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Παυλόπουλος, Βασίλης. "Κρίση αξιών ή οι αξίες της κρίσης: Σταθερότητα και μεταβολή προσωπικών και πολιτικών αξιών στην Ελλάδα της ύφεσης." Psychology: the Journal of the Hellenic Psychological Society 21, no. 3 (October 15, 2020): 334. http://dx.doi.org/10.12681/psy_hps.23502.

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This study aimed to explore patterns of stability and change of personal values, political values and ideology in Greece during the economic crisis. Based on the modernization theory (Inglehart, 1971, 2008) and the dual process motivational model for the determinants of political ideology (Duckitt & Sibley, 2010), we hypothesized that the perception of crisis as threatening will lead to a decrease in the importance of anxiety-free values and a shift towards conservatism. We also studied the relations between values and ideology, along with a structural model of these relationships on the basis of the theory across two time points. The sample consisted of 385 subjects (52% women, mean age 41.7 years) in 2009 and 521 subjects (50% women, mean age 38.7 years) in 2014. Participants filled in self-report questionnaires on their basic personal values (Schwarz et al., 2001), core political values (Schwartz et al., 2010) and political self-placement (left/right). Findings provided only partial support to the research hypotheses: a decline was found in self-transcendence values (universalism, equality), but at the same time in conservative values (tradition, conformity, security) as well, although the effect sizes were generally small. Agreement with conservative values led to stronger right political orientation at the secondtime point (2014). The stability of a two-component model of values and ideology was confirmed, consisting of openness vs. resistance to change, on one hand, and acceptance vs. rejection of inequality, on theother.

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Ma, Linquan, Karl Schwede, and Kazuma Shimomoto. "Local cohomology of Du Bois singularities and applications to families." Compositio Mathematica 153, no. 10 (July 27, 2017): 2147–70. http://dx.doi.org/10.1112/s0010437x17007321.

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In this paper we study the local cohomology modules of Du Bois singularities. Let $(R,\mathfrak{m})$ be a local ring; we prove that if $R_{\text{red}}$ is Du Bois, then $H_{\mathfrak{m}}^{i}(R)\rightarrow H_{\mathfrak{m}}^{i}(R_{\text{red}})$ is surjective for every $i$. We find many applications of this result. For example, we answer a question of Kovács and Schwede [Inversion of adjunction for rational and Du Bois pairs, Algebra Number Theory 10 (2016), 969–1000; MR 3531359] on the Cohen–Macaulay property of Du Bois singularities. We obtain results on the injectivity of $\operatorname{Ext}$ that provide substantial partial answers to questions in Eisenbud et al. [Cohomology on toric varieties and local cohomology with monomial supports, J. Symbolic Comput. 29 (2000), 583–600] in characteristic $0$. These results can also be viewed as generalizations of the Kodaira vanishing theorem for Cohen–Macaulay Du Bois varieties. We prove results on the set-theoretic Cohen–Macaulayness of the defining ideal of Du Bois singularities, which are characteristic-$0$ analogs and generalizations of results of Singh–Walther and answer some of their questions in Singh and Walther [On the arithmetic rank of certain Segre products, in Commutative algebra and algebraic geometry, Contemporary Mathematics, vol. 390 (American Mathematical Society, Providence, RI, 2005), 147–155]. We extend results on the relation between Koszul cohomology and local cohomology for $F$-injective and Du Bois singularities first shown in Hochster and Roberts [The purity of the Frobenius and local cohomology, Adv. Math. 21 (1976), 117–172; MR 0417172 (54 #5230)]. We also prove that singularities of dense $F$-injective type deform.

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Yuldashev, Tursun K., and Erkinjon T. Karimov. "Inverse Problem for a Mixed Type Integro-Differential Equation with Fractional Order Caputo Operators and Spectral Parameters." Axioms 9, no. 4 (October 20, 2020): 121. http://dx.doi.org/10.3390/axioms9040121.

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The questions of the one-value solvability of an inverse boundary value problem for a mixed type integro-differential equation with Caputo operators of different fractional orders and spectral parameters are considered. The mixed type integro-differential equation with respect to the main unknown function is an inhomogeneous partial integro-differential equation of fractional order in both positive and negative parts of the multidimensional rectangular domain under consideration. This mixed type of equation, with respect to redefinition functions, is a nonlinear Fredholm type integral equation. The fractional Caputo operators’ orders are smaller in the positive part of the domain than the orders of Caputo operators in the negative part of the domain under consideration. Using the method of Fourier series, two systems of countable systems of ordinary fractional integro-differential equations with degenerate kernels and different orders of integro-differentation are obtained. Furthermore, a method of degenerate kernels is used. In order to determine arbitrary integration constants, a linear system of functional algebraic equations is obtained. From the solvability condition of this system are calculated the regular and irregular values of the spectral parameters. The solution of the inverse problem under consideration is obtained in the form of Fourier series. The unique solvability of the problem for regular values of spectral parameters is proved. During the proof of the convergence of the Fourier series, certain properties of the Mittag–Leffler function of two variables, the Cauchy–Schwarz inequality and Bessel inequality, are used. We also studied the continuous dependence of the solution of the problem on small parameters for regular values of spectral parameters. The existence and uniqueness of redefined functions have been justified by solving the systems of two countable systems of nonlinear integral equations. The results are formulated as a theorem.

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Journal articles on the topic 'Partiti Partiti Schweiz'

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