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151.
Lai-Jiu Lin 《Journal of Global Optimization》2007,38(1):21-39
In this paper, we study an existence theorem of systems of generalized quasivariational inclusions problem. By this result,
we establish the existence theorems of solutions of systems of generalized equations, systems of generalized vector quasiequilibrium
problem, collective variational fixed point, systems of generalized quasiloose saddle point, systems of minimax theorem, mathematical
program with systems of variational inclusions constraints, mathematical program with systems of equilibrium constraints and
systems of bilevel problem and semi-infinite problem with systems of equilibrium problem constraints.
This research was supported by the National Science Council of the Republic of China. 相似文献
152.
We study the Friedmann-Robertson-Walker model with dynamical dark energy modelled in terms of the equation of state p
X
= w
X
(a(z)) ρ
X
in which the coefficient w
X
is parameterized by the scale factor a or redshift z. We use methods of qualitative analysis of differential equations to investigate the space of all admissible solutions for
all initial conditions on the two-dimensional phase plane. We show advantages of representing this dynamics as a motion of
a particle in the one-dimensional potential V(a). One of the features of this reduction is the possibility of investigating how typical big rip singularities are in the
future evolution of the model. The properties of potential function V can serve as a tool for qualitative classification of all evolution paths. Some important features like resolution of the
acceleration problem can be simply visualized as domains on the phase plane. Then one is able to see how large is the class
of solutions (labelled by the inset of the initial conditions) leading to the desired property. 相似文献
153.
A generalized inverse problem for the identification of the absorption coefficient for a hyperbolic system is considered. The well-posedness of the problem is examined. It is proved that the regular part of the solution is an L 2 function, which reduces the inverse problem to minimizing the error functional. The gradient of the functional is determined in explicit form from the adjoint problem, and approximate formulas for its calculation are derived. A regularization algorithm for the solution of the inverse problem is considered. Numerical results obtained for various excitation sources are displayed. 相似文献
154.
对解强刚性块线代数方程组X=(A(?)J)X φ,本文提出了L-收敛的最佳单参数迭代法(L-OOPI)和L-收敛的多参数迭代直接法(L-MPID),并给出了数值例子.数例表明,对于强刚性块线代数方程组,该二迭代法是有效的. 相似文献
155.
This paper considers the general synchronization dynamics of coupled Van der Pol–Duffing oscillators. The linear and nonlinear stability analysis on the synchronization process is derived through the Whittaker method and the Floquet theory in addition to the multiple time scales method. A stability map displaying different dynamical states of the system is performed. Numerical simulation is carried out to support and to complement the accuracy of the analytical treatment. 相似文献
156.
Supply Chain Management (SCM) is an important activity in all producing facilities and in many organizations to enable vendors,
manufacturers and suppliers to interact gainfully and plan optimally their flow of goods and services. To realize this, a
dynamic modelling approach for characterizing supply chain activities is opportune, so as to plan efficiently the set of activities
over a distributed network in a formal and scientific way. The dynamical system will result so complex that it is not generally
possible to specify the functional forms and the parameters of interest, relating outputs to inputs, states and stochastic
terms by experiential specification methods. Thus the algorithm that will presented is Data Driven, determining simultaneously
the functional forms, the parameters and the optimal control policy from the data available for the supply chain. The aim
of this paper is to present this methodology, by considering dynamical aspects of the system, the presence of nonlinear relationships
and unbiased estimation procedures to quantify these relations, leading to a nonlinear and stochastic dynamical system representation
of the SCM problem. Moreover, the convergence of the algorithm will be proved and the satisfaction of the required statistical
conditions demonstrated. Thus SCM problems may be formulated as formal scientific procedures, with well defined algorithms
and a precise calculation sequence to determine the best alternative to enact. A “Certainty equivalent principle” will be
indicated to ensure that the effects of the inevitable uncertainties will not lead to indeterminate results, allowing the
formulation of demonstrably asymptotically optimal management plans. 相似文献
157.
J. Keilson 《Annals of Operations Research》1987,9(1):439-447
A redundant system of independent repairable components with general failure time and repair time distributions is considered. It is shown that the system failure time has an expectation dependent only on the mean failure times and mean repair times of the components and not on their distributions. An intuitive argument is provided, based on the time of onset of the quasi-stationary distribution on the set of working states, to show that for highly reliable systems, the system failure time is exponentially distributed to good approximation. The argument also justifies a simple figure of merit for the quality of the exponential approximation. A key ingredient in the analysis is the system relaxation time, an informal review of which is provided. 相似文献
158.
J.E. Lorenzo H. Requardt 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,28(2):185-186
Eur. Phys. J. B 24, 315 (2001) Here we comment on a recently published paper on the presence of a phason contribution in the low temperature heat capacity data of the charge-density-wave compounds K0.3MoO3 and (TaSe4)2I. We have shown that the anomaly in the C
P
/
T
3
data reported by Odin et al. is straightforwardly interpreted in terms of low energy phonon modes resulting from the peculiar topology of these compounds.
Received 21 February 2002 Published online 19 July 2002 相似文献
159.
Blundell Tom L. Bolanos-Garcia Victor Chirgadze Dimitri Y. Harmer Nicholas J. Lo Thomas Pellegrini Luca Sibanda B. Lynn 《Structural chemistry》2002,13(3-4):405-412
Signaling in living systems needs to achieve high specificity, to be reversible, and to achieve high signal to noise. Signaling mediated by multiprotein systems has evolved that avoids the requirement for high-affinity binary complexes that would be difficult to reverse and which, in the overcrowded cell, would lead to excessive noise in the system. Symmetrical structures are only occasionally formed. When they are, it is principally to colocate components, for example, the tyrosyl kinases of growth factors, where dimers form. Symmetry is, however, often broken, presumably to create more sensitivity and specificity in the signaling system by assembling other components, into higher-order multiprotein systems. The binding of a single heparin to two 1:1 FGF:FGFR complexes is an example, as is the binding of a single ligase to the Xrcc4 dimer, perhaps so creating a further DNA-binding site. 相似文献
160.
R. Lü H. Pan J.-L. Zhu B.-L. Gu 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,26(4):479-491
The tunneling of a giant spin at excited levels is studied theoretically in mesoscopic magnets with a magnetic field at an
arbitrary angle in the easy plane. Different structures of the tunneling barriers can be generated by the magnetocrystalline
anisotropy, the magnitude and the orientation of the field. By calculating the nonvacuum instanton solution explicitly, we
obtain the tunnel splittings and the tunneling rates for different angle ranges of the external magnetic field ( θ
H = π/2 and π/2 < θ
H < π). The temperature dependences of the decay rates are clearly shown for each case. It is found that the tunneling rate
and the crossover temperature depend on the orientation of the external magnetic field. This feature can be tested with the
use of existing experimental techniques.
Received 12 March 2001 and Received in final form 18 October 2001 相似文献