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71.
Heng-You Lan 《Journal of Mathematical Analysis and Applications》2007,327(1):481-493
In this paper, we introduce and study a new system of nonlinear A-monotone multivalued variational inclusions in Hilbert spaces. By using the concept and properties of A-monotone mappings, and the resolvent operator technique associated with A-monotone mappings due to Verma, we construct a new iterative algorithm for solving this system of nonlinear multivalued variational inclusions associated with A-monotone mappings in Hilbert spaces. We also prove the existence of solutions for the nonlinear multivalued variational inclusions and the convergence of iterative sequences generated by the algorithm. Our results improve and generalize many known corresponding results. 相似文献
72.
A. C. Orifici R. S. Thomson R. Degenhardt C. Bisagni J. Bayandor 《Mechanics of Composite Materials》2007,43(1):9-28
Analysing the collapse of skin-stiffened structures requires capturing the critical phenomenon of skin-stiffener separation,
which can be considered analogous to interlaminar cracking. This paper presents the development of a numerical approach for
simulating the propagation of interlaminar cracks in composite structures. A degradation methodology was introduced in MSC.Marc,
which involved the modelling of a structure with shell layers connected by user-defined multiple-point constraints (MPCs).
User subroutines were written that employ the virtual crack closure technique (VCCT) to determine the onset of crack growth
and modify the properties of the user-defined MPCs to simulate crack propagation. Methodologies for the release of failing
MPCs are presented and are discussed with reference to the VCCT assumption of self-similar crack growth. The numerical results
obtained by using the release methodologies are then compared with experimental data for a double-cantilever beam specimen.
Based on this comparison, recommendations for the future development of the degradation model are made, especially with reference
to developing an approach for the collapse analysis of fuselage-representative structures.
Russian translation published in Mekhanika Kompozitnykh Materialov, Vol. 43, No. 1, pp. 15–42, January–February, 2007. 相似文献
73.
A layer of stratified combination composed of selected radiation shielding materials acquires better shielding property. Albedo
is used in such measurements as an integral measure ofγ-ray scattering. The stratified slabs of alternating heterogeneous layers have been found to have a virtual homogeneous property
with a definite effective atomic number. The angular distribution of back-scattered photons as well as the total number albedo
values for iron, aluminium and concrete in stratified combination for 662 keV and 1250 keV photons are reported. 相似文献
74.
We present a new linearized model for the zero-one quadratic programming problem, whose size is linear in terms of the number of variables in the original nonlinear problem. Our derivation yields three alternative reformulations, each varying in model size and tightness. We show that our models are at least as tight as the one recently proposed in [7], and examine the theoretical relationship of our models to a standard linearization of the zero-one quadratic programming problem. Finally, we demonstrate the efficacy of solving each of these models on a set of randomly generated test instances. 相似文献
75.
In this work we display a numerical comparison, under statistical and computational point of view, between semi-analytical Eulerian and Lagrangian dispersion models to simulate the ground-level concentration values of a passive pollutant released from a low height source. The Eulerian approach is based on the solution of the advection–diffusion equation by the Laplace transform technique. The Lagrangian approach is based on solution of the Langevin equation through the Picard’s Iterative Method. Turbulence inputs are calculated according to a parameterization capable of generating continuous values in all stability conditions and in all heights of the Planetary Boundary Layer (PBL). Numerical simulations and comparisons show a good agreement between predicted and observed concentrations values. The comparison reveals the main advantages and disadvantages between the models. 相似文献
76.
77.
We consider a discrete-time stochastic model of an ECN/RED gateway where competing TCP sources share the link capacity. As
the number of competing flows becomes large, the asymptotic queue behavior (normalized by the number of flows) at the gateway
can be described by a simple recursion and the throughput behavior of individual TCP flows becomes asymptotically independent.
A Central Limit Theorem complement is also presented, yielding a more accurate characterization of the asymptotic queue size.
These results suggest a scalable yet accurate model of this complex large-scale stochastic feedback system, and crisply reveal
the sources of queue fluctuations.
This work was prepared through collaborative participation in the Communications and Networks Consortium sponsored by the
U.S. Army Research Laboratory under the Collaborative Technology Alliance Program, Cooperative Agreement DAAD19-01-2-0011.
This work was also supported by the Space and Naval Warfare Systems Center—San Diego under Contract No: N66001-00-C-8063.
The views and conclusions contained in this document are those of the authors and should not be interpreted as representing
the official policies, either expressed or implied, of the Army Research Laboratory or the U.S. Government. 相似文献
78.
毛细管电色谱研究进展 总被引:7,自引:2,他引:7
毛细管电色谱是一种新兴的具有高效,高选择性的微分离技术。本文评述了毛细管电色说的发展状况和相关的技术,并对其发展前景进行了展望,引用文献24篇 。 相似文献
79.
The solid diffusion coefficient of lithium-ion in LiCoO2 cathode material has been investigated by the capacity intermittent titration technique (CITT) at different voltages and at different charge/discharge cycles. By SEM, XRD and FTIR techniques, the structure of LiCoO2 was studied before and after charge-discharge cycles, and the relationship between solid diffusion coefficient and crystal structure was further discussed. CITT results show that the value of Li+ solid diffusion coefficient of LiCoO2 is about 10-12 cm2·s-1. During the whole charge-discharge cycles, the Li+ solid diffusion coefficient decreased within the voltage of 4.0~4.3 V, which is attributed to the change of the structure of LiCoO2. 相似文献
80.