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101.
C. S. Unnikrishnan 《Pramana》2005,65(3):359-379
I discuss in detail the result that the Bell’s inequalities derived in the context of local hidden variable theories for discrete
quantized observables can be satisfied only if a fundamental conservation law is violated on the average. This result shows
that such theories are physically nonviable, and makes the demarcating criteria of the Bell’s inequalities redundant. I show
that a unique correlation function can be derived from the validity of the conservation law alone and this coincides with
the quantum mechanical correlation function. Thus, any theory with a different correlation function, like any local hidden
variable theory, is incompatible with the fundamental conservation laws and space-time symmetries. The results are discussed
in the context of two-particle singlet and triplet states, GHZ states, and two-particle double slit interferometry. Some observations
on quantum entropy, entanglement, and nonlocality are also discussed. 相似文献
102.
Ruggero Maria Santilli 《Foundations of Physics》2003,33(9):1373-1416
Pre-existing mathematical formulations are generally used for the treatment of new scientific problems. In this note we show that the construction of mathematical structures from open physical, chemical, and biological problems leads to new intriguing mathematics of increasing complexity called iso-, geno-, and hyper-mathematics for the treatment of matter in reversible, irreversible, and multi-valued conditions, respectively, plus anti-isomorphic images called isodual mathematics for the treatment of antimatter. These novel mathematics are based on the lifting of the multiplicative unit of ordinary fields (with characteristic zero) from its traditional value +1 into: (1) invertible, Hermitean, and single-valued units for isomathematics; (2) invertible, non-Hermitean, and single-valued units for genomathematics; and (3) invertible, non-Hermitean, and multi-valued units for hypermathematics; with corresponding liftings of the conventional associative product and consequential lifting of all branches of mathematics admitting a (left and right) multiplicative unit. An anti-Hermitean conjugation applied to the totality of quantities and their operation of the preceding mathematics characterizes the isodual mathematics. Intriguingly, the emerging formulations preserve the abstract axioms of conventional mathematics (that based on the unit +1). As such, the new formulations result to be new realizations of existing abstract mathematical axioms. We then show that the above mathematical advances permit corresponding liftings of conventional classical and quantum theories with a resolution of basic open problems in physics, chemistry, and biology, numerous experimental verifications, as well as new industrial applications. 相似文献
103.
在逐步增加的型截尾模型下,研究部件寿命服从双参数指数分布的冷贮备串联系统可靠性指标的Bayes估计及单样本场合未来观测值的预测问题.在两个参数均未知的情形下,分别在平方损失(SE)、LINEX损失和熵(General Entropy,GE)损失函数下给出两个参数及可靠性指标的Bayes估计,对于超参数的确定,给出一种新的方法;并讨论了单样本场合未来观测值的预测问题,给出预测分布及预测区间;最后利用随机模拟方法进行比较,并对结果进行了讨论. 相似文献
104.
TESTING DIFFERENT CONJUGATE GRADIENT METHODS FOR LARGE—SCALE UNCONSTRAINED OPTIMIZATION 总被引:6,自引:0,他引:6
Yu-hongDai QinNi 《计算数学(英文版)》2003,21(3):311-320
In this PaPer we test different conjugate gradient (CG) methods for solving large-scale unconstrained optimization problems.The methods are divided in two groups:the first group includes five basic CG methods and the second five hybrid CG methods.A collection of medium-scale and large-scale test problems are drawn from a standard code of test problems.CUTE.The conjugate gradient methods are ranked according to the numerical results.Some remarks are given. 相似文献
105.
China, as one of the members of ITER (international thermonuclear experimental reactor) project, one of the most important construction tasks is the fabrication of the first wall panel and shield blankets, which is the key engineering technology of ITER construction and might be one of the crucial issues of the future reactor too. Since 2004, an associated research team including Southwestern Institute of Physics ( SWIP ), Ninxia Non-ferrous Metal Co. Itd and Chinese Institute of Engineering Physics, as well as Nuclear Power Institute of China has been established. Up to now, several series of interlayer for hot isostatic press ( HIP ) connection of beryllium and CuCrZr alloy have been tested. They are titanium film or coating, Cu coating and Al or AISiMg alloy etc. The bonding strength (tensile or shear strength ) of HIPed Be/Cu joints is up to 100 MPa. 相似文献
106.
In the field of combinatorial optimization, it may be possible to more accurately represent reality through stochastic models rather than deterministic ones. When randomness is present in a problem, algorithm designers face new difficulties which complicate their task significantly. Finding a proper mathematical formulation and a fast evaluation of the objective function are two major issues. In this paper we propose a new tabu search algorithm based on sampling and statistical tests. The algorithm is shown to perform well in a stochastic environment where the quality of feasible solutions cannot be computed easily. This new search principle is illustrated in the field of cause and effect analysis where the true cause of an undesirable effect needs to be eliminated. A set of n potential causes is identified and each of them is assumed to be the true cause with a given probability. The time to investigate a cause is a random variable with a known probability distribution. Associated with each cause is the reward obtained if the cause is really the true cause. The decision problem is to sequence the n potential causes so as to maximize the expected reward realized before a specified time horizon. 相似文献
107.
108.
In this paper we explore the usefulness of induced-order statistics in the characterization of integrated series and of cointegration
relationships. We propose a non-parametric test statistic for testing the null hypothesis of two independent random walks
against wide cointegrating alternatives including monotonic nonlinearities and certain types of level shifts in the cointegration
relationship. We call our testing device the induced-order Kolmogorov–Smirnov cointegration test (KS), since it is constructed
from the induced-order statistics of the series, and we derive its limiting distribution. This non-parametric statistic endows
the test with a number of desirable properties: invariance to monotonic transformations of the series, and robustness for
the presence of important parameter shifts. By Monte Carlo simulations we analyze the small sample properties of this test.
Our simulation results show the robustness of the induced order cointegration test against departures from linear and constant
parameter models.
This paper is an extension of the work of Aparicio and Granger (1995) and Aparicio and Escribano (1998). 相似文献
109.
Victor Aguirre-Torres 《Statistics & probability letters》1985,3(6):317-324
A test for the problem of choosing between several nonnested nonlinear regression models simultaneously is presented. The test does not require an explicit specification of a parametric family of distributions for the error term and has a closed form. 相似文献
110.
Effects of multiple blade interaction on the containment of blade fragments during a rotor failure 总被引:12,自引:0,他引:12
A finite element analysis is used to study the impact and the containment aspects of rotor blade fragments that are produced during a aircraft jet engine rotor failure. The impact and containment studies are performed on a ring-type containment structure and various fragment types are considered in this study. For each type of fragment, the ring thickness is varied incrementally and the ring response, residual kinetic energy level of the fragments, magnitude of impact forces and the overall containment or failure are determined. First, only a single fragment is considered and the rotor is assumed to contain no other blades. Next, the remaining blades are introduced and the effects of multiple collisions with the other blades on the containment are analyzed. The explicit, nonlinear finite element code Dyna3d is used for the numerical computations in this study and the results are compared with the experimental results performed on a T58 rotor at the spin facility of the Naval Air Propulsion Test Center. 相似文献