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991.
992.
本文研究了线性模型的最小二乘估计的中偏差.通过估计Laplace渐近积分,得到了随机误差为取值于Rd的相互独立同分布随机变量情形下的中偏差与重对数律的结果. 相似文献
993.
994.
本文研究了一般Gauss-Markov模型中线性可预测变量的线性预测的可容许性.在给出线性预测可容许性定义的基础上,通过构造一个特殊的常量矩阵D0,分别得到了齐次和非齐次线性预测类中可容许的充要条件. 相似文献
995.
本文研究固定设计下的半参数回归模型在相应变量Yi因受到某种随机干扰而被右截断且截断分布已知时,利用所获的截断观察定义了参数β和回归函数g(·)的估计,并证明了它们均具有强相合性. 相似文献
996.
Lubomír Kubáček 《Mathematica Slovaca》2007,57(1):59-82
In some situations estimates of unknown parameters must be corrected by additional measurements. It is in principle no problem
to calculate the corrected estimates, however, it is of more interest to find formulae for correction itself. The formulae
enable us to design an additional experiment and to judge its usefulness.
The aim of the paper is to find such formulae for several situations.
Supported by the grant of the Council of Czech Government MSM 6 198 959 214. 相似文献
997.
We consider nonholonomic systems with linear, time-independent constraints subject to positional conservative active forces.
We identify a distribution on the configuration manifold, that we call the reaction-annihilator distribution ℜ°, the fibers
of which are the annihilators of the set of all values taken by the reaction forces on the fibers of the constraint distribution.
We show that this distribution, which can be effectively computed in specific cases, plays a central role in the study of
first integrals linear in the velocities of this class of nonholonomic systems. In particular we prove that, if the Lagrangian
is invariant under (the lift of) a group action in the configuration manifold, then an infinitesimal generator of this action
has a conserved momentum if and only if it is a section of the distribution ℜ°. Since the fibers of ℜ° contain those of the
constraint distribution, this version of the nonholonomic Noether theorem accounts for more conserved momenta than what was
known so far. Some examples are given.
相似文献
998.
O. Yu. Dashkova 《Algebra and Logic》2007,46(5):297-302
We are concerned with infinite-dimensional locally soluble linear groups of infinite central dimension that are not soluble
A3-groups and all of whose proper subgroups, which are not soluble A3-groups, have finite central dimension. The structure of groups in this class is described. The case of infinite-dimensional
locally nilpotent linear groups satisfying the specified conditions is treated separately. A similar problem is solved for
infinite-dimensional locally soluble linear groups of infinite fundamental dimension that are not soluble A3-groups and all of whose proper subgroups, which are not soluble A3-groups, have finite fundamental dimension.
__________
Translated from Algebra i Logika, Vol. 46, No. 5, pp. 548–559, September–October, 2007. 相似文献
999.
Evald Übi 《Central European Journal of Mathematics》2007,5(2):373-385
The system of inequalities is transformed to the least squares problem on the positive ortant. This problem is solved using
orthogonal transformations which are memorized as products. Author’s previous paper presented a method where at each step
all the coefficients of the system were transformed. This paper describes a method applicable also to large matrices. Like
in revised simplex method, in this method an auxiliary matrix is used for the computations. The algorithm is suitable for
unstable and degenerate problems primarily.
相似文献
1000.
Fabien Tricoire 《4OR: A Quarterly Journal of Operations Research》2007,5(2):165-168
We present an overview of the author’s Ph.D. thesis, supervised by P. Dejax and N. Bostel, which was defended in February
2006 at école des Mines de Nantes, France. The thesis is written in French, and is available at . It was conducted in the context of a research contract with a water distribution company. In a first section, we define
multiperiod routing problems for service technicians. In a second section, we present some heuristics and a memetic algorithm
used to solve these problems. The third section introduces optimal and near-optimal approaches based on column generation.
Finally, we present some applications to the real-life case. The methods presented in Sects. 2, 3 and 4 were tested over several
sets of problems, based on real-life statistics provided by the company.
相似文献