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101.
We study the properties of QCD vacuum state in this paper. The values of various local quark vacuum condensates, quark-gluon mixed vacuum condensates, and the structure of non-local quark vacuum condensate are predicted by the solution of Dyson-Schwinger Equations in "rainbow" approximation with three sets of different parameters for effective gluon propagator. The light quark virtuality is also obtained in a consistent way. Our all theoretical results here are in good agreement with the empirical values used widely in literature and many other theoretical calculations. 相似文献
102.
This paper deals with a phase transitions model describing the evolution of damage in thermoviscoelastic materials. The resulting system is highly non-linear, mainly due to the presence of quadratic dissipative terms and non-smooth constraints on the variables. Existence and uniqueness of a solution are proved, as well as regularity results, on a suitable finite time interval. 相似文献
103.
The existence and uniqueness of the weak solution to the model for the dynamics of a viscoelastic rod which is in adhesive contact with an obstacle is established. The model consists of a hyperbolic equation for the vibrations of the rod coupled with a nonlinear ordinary differential equation (ODE) for the evolution of the bonding function. The model allows for failure, i.e., complete debonding, in finite time. The existence of the weak solution is established by using an existence result for ODEs and the Schauder fixed-point theorem. The limit of an elastic rod when the viscosity vanishes is studied, too. 相似文献
104.
E. Demidenko 《Journal of Optimization Theory and Applications》2008,136(3):375-395
We develop criteria for the existence and uniqueness of the global minima of a continuous bounded function on a noncompact
set. Special attention is given to the problem of parameter estimation via minimization of the sum of squares in nonlinear
regression and maximum likelihood. Definitions of local convexity and unimodality are given using the level set. A fundamental
theorem of nonconvex optimization is formulated: If a function approaches the minimal limiting value at the boundary of the
optimization domain from below and its Hessian matrix is positive definite at the point where the gradient vanishes, then
the function has a unique minimum. It is shown that the local convexity level of the sum of squares is equal to the minimal
squared radius of the regression curvature. A new multimodal function is introduced, the decomposition function, which can
be represented as the composition of a convex function and a nonlinear function from the argument space to a space of larger
dimension. Several general global criteria based on majorization and minorization functions are formulated. 相似文献
105.
106.
Summary
K-absorption edge shifts of the absorbing atom in its complexes have been correlated with the effective nuclear charge on the
central metal ion, overall electronegativity difference between the nearest neighbours in the complexes and the ionic radius
of the central metal ion; a linear correlation has been observed among them, the data subjected to the method of least squares
indicated that the correlation is genuine.
Riassunto Gli slittamenti dell’orlo di assorbimentoK dell’atomo assorbente nei suoi complessi sono stati correlati con la carica nucleare efficacie sullo ione metallico centrale, con la differenza di elettronegatività generale tra vicini prossimi nei complessi e col raggio ionico dello ione metallico centrale; una correlazione lineare è stata osservata tra loro, i dati soggetti al metodo dei minimi quadranti hanno indicato che la correlazione è genuina.相似文献
107.
Jian-Wen Peng 《Journal of Global Optimization》2008,42(4):559-575
In this paper, we introduce a new system of generalized mixed quasi-variational-like inclusions with (A, η, m)-accretive operators and relaxed cocoercive mappings. By using the fixed point theorem of Nadler, we prove the existence
of solutions for this general system of generalized mixed quasi-variational-like inclusions and its special cases. The results
in this paper unify, extend and improve some known results in the literature. The novel proof method is simpler than those
iterative algorithm approach for proving the existence of solutions of all classes of system of set-valued variational inclusions
in the literature. 相似文献
108.
The fluorescent spectrum and the excitation spectrum were used to present the cluster molecular structure feature in ethanol-water solutions.Through analyzing the fluorescent characteristics of an excimer,it is proposed that the excimers are formed between the ethanol-water cluster molecules in the excited state and in the ground state.The fluorescent lifetime and the fluorescent intensity decay process give information about the photo-physical and photo-chemical processes of the formation and the dissociation of an excimer.The theoretical calculation and physical analysis coincide with the experimental results.The preliminary conclusion about the structure feature of ethanol-water cluster molecule is that it has a planar one like a sandwich. 相似文献
109.
Project Scheduling with Multiple Modes: A Genetic Algorithm 总被引:10,自引:0,他引:10
Sönke Hartmann 《Annals of Operations Research》2001,102(1-4):111-135
In this paper we consider the resource-constrained project scheduling problem with multiple execution modes for each activity and makespan minimization as objective. We present a new genetic algorithm approach to solve this problem. The genetic encoding is based on a precedence feasible list of activities and a mode assignment. After defining the related crossover, mutation, and selection operators, we describe a local search extension which is employed to improve the schedules found by the basic genetic algorithm. Finally, we present the results of our thorough computational study. We determine the best among several different variants of our genetic algorithm and compare it to four other heuristics that have recently been proposed in the literature. The results that have been obtained using a standard set of instances show that the new genetic algorithm outperforms the other heuristic procedures with regard to a lower average deviation from the optimal makespan. 相似文献
110.
In this paper, we prove the existence of weak solutions and investigate uniform decay rates of global weak solutions for a
hyperbolic hemivariational inequalitiy of dynamic elasticity.
This work was supported by the Korea Research Foundation Grant funded by the Korean Government (MOEHRD, Basic Research Promotion
Fund) (KRF-2007-355-C00002). 相似文献