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991.
Nibedita Bandyopadhyay Ananda Sen 《Annals of the Institute of Statistical Mathematics》2005,57(4):703-732
Nonhomogeneous Poisson process (NHPP) is a commonly used stochastic model that is utilized to describe the pattern of repeated
occurrence of certain events or conditions. Aninhomogeneous gamma process evolves as a generalization to NHPP, where the observed failure epochs correspond to every successive κ-th event of the underlying
Poisson process, κ being an unknown parameter to be estimated from the data. This article focuses on a special class of inhomogeneous
gamma process, calledmodulated power law process (MPLP) that assumes the Weibull form of the intensity function. The traditional power law process is a popular stochastic
formulation of certain empirical relationships between the time to failure and the cumulative number of failures, often observed
in industrial experiments. The MPLP retains this underlying physical basis and provides a more flexible modeling environment
potentially leading to a better fit to the failure data at hand. In this paper, we investigate inference issues related to
MPLP. The maximum likelihood estimators (MLE’s) of the model parameters are not in closed form and enjoy the curious property
that they are asymptotically normal with a singular variance-covariance matrix. Consequently, the derivation of the large-sample
results requires non-standard modifications of the usual arguments. We also propose a set of simple closed-form estimators
that are asymptotically equivalent to the MLE’s. Extensive simulation results are carried out to supplement the theoretical
findings. Finally, we implement our inference results to a failure dataset arising from a repairable system. 相似文献
992.
M. Dutta 《Journal of statistical physics》1972,5(1-2):127-131
In an essentially statistical approach to statistical mechanics, it is seen that the Gauss principle of the arithmetic mean may be taken as the starting point. The equations from which the subject can be built up are deduced from the Gauss principle of the arithmetic mean. 相似文献
993.
By means of the Monte Carlo sampling technique the equilibrium thermodynamics of fluids and magnets can be calculated numerically. We show that the questions of convergence and accuracy of this method can be understood in terms of the dynamics of the appropriate stochastic model. Also, we discuss to what extent various choices of transition probabilities lead to different dynamic properties of the system. As examples of applications, we consider Ising and Heisenberg spin systems. The numerical results about the dynamic correlation functions are compared to simple approximations taken from the theory of the kinetic Ising model. 相似文献
994.
A model for multiparticle production process in high-energy hadronic collisions is proposed. In the centre of mass (CM) system
of colliding particles the target and the projectile are assumed to pass through each other sharing energies allowed by kinematical
constraints. Thus in app collision the energy associated with each is √S/2 (S being the square of the CM energy) which is taken to be the real variable that governs the number of particles produced.
In the case of hadronnucleus collisions the projectile and the target ofv nucleons lying in a (Lorentz contracted) tube pass through each other sharing energies ⋍ √S
A2, whereS
A ⋍vS. Before the final state particles emerge from these systems, the constituents of the target, i.e.,v nucleons share equally (= √S
A2v) the total energy associated with the target and become the centres from which final state particles stem out. Several results
have been discussed. 相似文献
995.
We study the set of equilibrium states for quantum lattice states in the presence of a translation symmetry of the model. We derive a characterization of the spontaneous breaking of this symmetry, i.e., the decomposition of an invariant equilibrium state into a mixture of noninvariant equilibrium states, in terms of the separability in mean energy of these states for a class of perturbed dynamics. 相似文献
996.
R. C. Gauthier 《Optics & Laser Technology》1993,25(5)
In this paper the power coupling expression between two identical axially aligned and spatially separated waveguides is presented. Calculations using the coupling expression for a Gaussian mode profile in the input waveguide produce results that are in excellent agreement with experimental observations. 相似文献
997.
楼红卫 《宁波大学学报(理工版)》1996,(1)
如果M(a)是n维正数组a=(a1,a2,…,an)的一种平均,则称不等式为关于平均M的Holder不等式,文章着重研究了关于广义对数平均的Holder不等式.证明了当r>-1时,关于Lr的Hlder不等式成立,而当r<-1时,关于Lr的反向Holder不等式成立.对于一些常见的平均,例如算术平均、几何平均、调和平均、Heron平均、对数平均和指数平均,文章证明了关于这些平均的Holder不等式成立,而对于反调和平均,关于该平均的Hlder不等式和反向Hlder不等式都不恒成立. 相似文献
998.
In a recently suggested variational quantum field theoretical approach the angular momentum and isospin properties of the
pion field surrounding a quark bag are investigated using the Lagrangian of the Cloudy Bag Model. 相似文献
999.
M. A. Abdel-Halim G. S. Christensen D. H. Kelly 《Journal of Optimization Theory and Applications》1985,45(4):517-531
A new approach for designing a linear regulator for the problem of load frequency control (LFC) of interconnected power systems is developed. The control is specified to be of proportional-plus-integral (P-I) form and is only a function of the measurable states. The LFC problem is formulated as a parameter optimization problem.This work was supported in part by the National Research Council of Canada, Grant No. A4146. 相似文献
1000.
Theoretical expressions for the overall values of the conventional discrepancy indicesR(F) andR(I) are derived for a non-centrosymmetric crystal with a centrosymmetric group by taking the centrosymmetric group and a part
of the other atoms in the unit cell as the trial structure. These results are used to obtain tables of values of these indices
in terms of the parameter σ
1c
2
and σ
1
2
which define the fractional contribution to the local mean intensity from the centrosymmetric group and all the known atoms
respectively.
Contribution No. 561 相似文献