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991.
992.
Jianghua Fan 《Journal of Mathematical Analysis and Applications》2008,337(2):1041-1047
In this paper, we study the existence of solutions and approximation of the solutions by using a Mann type iterative scheme for variational inequalities in noncompact subsets of Banach spaces. The results presented in this paper generalize the corresponding results of J. Li [J. Li, On the existence of solutions of variational inequalities in Banach spaces, J. Math. Anal. Appl. 295 (2004) 115-126]. 相似文献
993.
Zhenhai Liu Stanisaw Migrski Anna Ochal 《Journal of Mathematical Analysis and Applications》2008,340(2):1347-1361
In this paper we consider a mathematical model describing static elastic contact problems with the Hooke constitutive law and subdifferential boundary conditions. We treat boundary hemivariational inequalities which are weak formulations of contact problems. We establish existence and uniqueness of solutions to hemivariational inequalities. Using the notion of H-convergence of elasticity tensors we investigate the limit behavior of the sequence of solutions to hemivariational inequalities. 相似文献
994.
V. G. Morozov 《Theoretical and Mathematical Physics》2008,154(1):85-93
Using the nonequilibrium statistical operator method and the projection technique, we derive the system of exact relaxation
equations for a quantum system interacting with an alternating external field. These equations hold in the case where some
of the basic dynamical variables describing a nonequilibrium state depend explicitly on time. We obtain the exact expression
for the entropy production in an alternating external field.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 154, No. 1, pp. 102–112, January, 2008. 相似文献
995.
We consider the model of the one-dimensional cookie random walk when the initial cookie distribution is spatially uniform
and the number of cookies per site is finite. We give a criterion to decide whether the limiting speed of the walk is non-zero.
In particular, we show that a positive speed may be obtained for just three cookies per site. We also prove a result on the
continuity of the speed with respect to the initial cookie distribution.
相似文献
996.
In this paper a control strategy is formulated that minimizes the costs for a single chemical cleaning of a dead-end ultra filtration membrane. From the process model, the performance index and the constraints it can be derived that dynamic optimization will lead to a ‘maximum effort control problem’, in which the controls (cleaning flow and cleaning agent concentration) are either zero or maximum. The change from maximum to zero is called the switching point. This switching point depends on the overall cleaning time and the requested cleaning effectiveness. From the calculated optimal control strategy it follows that cleaning time can be significantly reduced, compared to conventional cleaning. 相似文献
997.
Phase‐pure ammonium catena‐polyphosphate IV [NH4PO3]x was synthesized by heating NH4H2PO4 in a tube furnace under an ammonia gas flow. The product contained single crystals of [NH4PO3]x IV appropriate for an X‐ray structure determination enabling structure refinement of this compound. The pseudo‐merohedrally twinned crystals of [NH4PO3]x crystallize in the monoclinic crystal system (P21/c, no. 14, a = 2270.3(5), b = 458.14(9), c = 1445.1(3) pm, β = 108.56(3)°, Z = 4, 2264 data, R1 = 0.076). In the unit cell the catena‐polyphosphate chain anions run parallel [010] with a chain‐periodicity P = 2 and a stretching factor fs = 0.94. The chain anions are interconnected through extensive hydrogen bonding towards the ammonium ions. Due to ‘chemical twinning’ a novel catena‐polyphosphate structure type is realized in [NH4PO3]x IV. The vibrational spectra of [NH4PO3]x IV are reported as well. 相似文献
998.
999.
Successful demonstration of selective area doping of planar glass samples for monolithic integration of optically passive and active devices on a single chip is presented. Salt solution of erbium was delivered onto pre-sintered germano-silicate samples via a syringe. The samples were then consolidated to form dense glass layers containing regions doped with rare earth. Erbium tri-chloride solution, 0.1 M, was used during the solution doping phase, with the resulting erbium atomic percentage ranging from more than 0.1-0.4%, increasing linearly with the number of drips applied. 相似文献
1000.