The reservoir technique: a way to make Godunov-type schemes zero or very low diffuse. Application to Colella–Glaz solver

Although it is commonly thought that first order schemes are not accurate enough to approximate nonlinear hyperbolic problems, we here explore a conservative time integration with global time steps but local updates (see [F. Alouges, F. De Vuyst, G. Le Coq, E. Lorin, Un procédé de réduction de la diffusion numérique des schémas à différence de flux d'ordre un pour les systèmes hyperboliques non linéaires, C. R. Math. Acad. Sci. Paris, Ser. I 335 (7) (2002) 627–632. [1]]; [F. Alouges, F. De Vuyst, G. Le Coq, E. Lorin, The reservoir scheme for systems of conservation laws, in: Finite Volumes for Complex Applications, III, Porquerolles, 2002, Lab. Anal. Topol. Probab. CNRS, Marseille, 2002, pp. 247–254 (electronic). [2]]). This overall conservative method can be interpreted as a system of reservoirs at cell interfaces that fill up and empty when local CFL conditions are reached. For Euler equations, particularly good results are obtained when one uses this technique together with the Riemann solver proposed by Colella and Glaz.     

Nontrivial structural organization of pivalate complexes with the fragment {Fe2Li(μ3-O)}

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Controle de la qualite des materiaux colles a partir du mode vertical

The paper presents measurements by transmission of an ultrasonic wave on glued sheet immersed in water. The experiments was performed by varying the incidence angle. The study has been undertaken on structures consisting of two identical plates either of aluminium or of steel glued by an epoxy resin. The obtained results reveal the existence of a vertical mode which allows to control the quality of the assembly.     

The influence of perceived stock value price histories in the mean–variance-instability model

The model introduced by H. Talpaz, A. Harpaz and J.B. Penson (1984. European Journal of Operational Research 14, 262–269) extends the mean–variance model introducing the concept of instability. In this way it is possible to see an investor's attitude towards predicted instability. In this paper we show how optimisation procedures based on penalty (or preferred) weighted instability matrices can be interpreted in terms of real time utility functions which depend on an `actual' and a `remembered' time series due to fading memory. This approach justifies some bounded normalised functions used to represent the investors preference between the irregular frequency fluctuations.     

The arbitrage pricing theorem with incomplete preferences

This paper proves existence of equilibrium and the arbitrage pricing theorem for an asset exchange economy, where individuals' preferences may be incomplete or intransitive. This extends existing results to more general preferences. We also prove the arbitrage pricing theorem for a theory of choice under uncertainty by Bewley [Bewley, T. F. (2002), Knightian decision theory: part I, Decisions in Economics and Finance 25, 79–110.]. These preferences model Knightian uncertainty by preferences which may be incomplete but satisfy independence.     

Palladium(II) and platinum(II) complexes of 6-methyl-2-acetylpyridine 3-hexamethyleneiminylthiosemicarbazones: A structural and spectral study

The reaction of 6-methyl-2-acetylpyridine 3-hexamethyleneiminyl-thiosemicarbazone, H6MAchexim, with potassium tetrachloropalladate(II) and tetrachloroplantinate(II) in methanol afforded the complexes [Pd(6MAchexim)Cl] and [Pt(6MAchexim)Cl], respectively. The X-ray crystal structure determination of both shows that anions of H6MAchexim coordinate in a planar conformation to the central palladium(II) or platinum(II) via the pyridyl nitrogen, azomethine nitrogen and thiolato sulfur atoms. The complexes have also been characterized by spectroscopic techniques (IR, UV–VIS and ¹H NMR).     

Synchronization of the fractional order hyperchaos Lorenz systems with activation feedback control

Based on the stability theory of fractional order systems, this paper analyses the synchronization conditions of the fractional order chaotic systems with activation feedback method. And the synchronization of commensurate order hyperchaotic Lorenz system of the base order 0.98 is implemented based on this method. Numerical simulations show the effectiveness of this method in a class of fractional order chaotic systems.