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991.
双模纠缠相干光场控制下双光子过程中有效二能级原子的信息熵压缩 总被引:1,自引:1,他引:0
根据量子信息理论,研究了与双模纠缠相干场相互作用双光子过程中有效二能级原子的信息熵压缩.讨论了场的初态对信息熵压缩的因影响,并且比较了分别从基于信息熵测不准关系和海森堡测不准关系出发得出的结果.结果表明:信息熵压缩的稳定周期性、压缩方向分别由场的平均光子数和方向角控制,场的纠缠度对信息熵压缩不产生影响.信息熵压缩实现了对原子压缩效应的高灵敏量度. 相似文献
992.
Li-Chun Zhang Huai-Fan Li Ren Zhao Yue-Qin Wu 《International Journal of Theoretical Physics》2008,47(7):2021-2028
Recently, there has been much attention devoted to resolving the quantum corrections to the Bekenstein-Hawking black hole
entropy. In particular, many researchers have expressed a vested interest in the coefficient of the logarithmic term of the
black hole entropy correction term. In this paper, based on the correction to black hole thermodynamic quantity due to the
generalized uncertainty principle, we calculate the partition function by energy spectrum obtained using tunneling effect.
Furthermore we derive the black hole entropy. In the expression, we not only consider the generalized uncertainty principle
but also consider the departure of black hole radiation spectrum from pure thermal spectrum. According to criterion law of
thermodynamic systems phase transition, we discuss the phase transition of AdS black hole and derive that the phase transition
of AdS black hole is a secondary one. 相似文献
993.
In order to investigate the features of a multiple-part musical score which enhance its appeal to the listener’s ear, this study performs a robust analysis of the correlation between two musical sequences. In the proposed approach, a series of notes are extracted from seven well-known classical pieces of music and are converted into one-variable “music walks”. The linear correlation between pairs of music walks is assessed using the conventional linear correlation coefficient, while the nonlinear correlation is examined using the mutual information concept. The results show that even though two musical time walks may exhibit virtually no linear correlation, they invariably have a certain degree of nonlinear correlation. In other words, to truly understand the correlation between two musical sequences, it is necessary to consider not only the linear correlation between them, but also the nonlinear correlation. In addition, it is shown that the normalized mutual information coefficient between musical sequences has a relatively low value and varies significantly over the course of the musical score. Thus, it can be inferred that the appeal of a musical score stems at least in part from significant variations in both the melody and the rhythm of the constituent parts such that the overall score has a rich and unpredictable property. 相似文献
994.
Zhang Ya Hu Shuang-Qi Zhao Ren Li Huai-Fan 《International Journal of Theoretical Physics》2008,47(2):520-525
Recently, there has been much attention devoted to resolving the quantum corrections to the Bekenstein-Hawking black hole
entropy. In particular, many researchers have expressed a vested interest in the coefficient of the logarithmic term of the
black hole entropy correction term. In this paper, we calculate the correction value of the black hole entropy by utilizing
the generalized uncertainty principle and obtain the correction term caused by the generalized uncertainty principle. Because
in our calculation we think that the Bekenstein-Hawking area theorem is still valid after considering the generalized uncertainty
principle, we derive that the coefficient of the logarithmic term of the black hole entropy correction term is positive. This
result is different from the known result at present. Our method is valid not only for single horizon spacetime but also for
spin axial symmetric spacetimes with double horizons. In the whole process, the physics idea is clear and calculation is simple.
It offers a new way for studying the entropy correction of the complicated spacetime. 相似文献
995.
文章介绍了迈克尔逊干涉仪修正系数的求解过程,讨论了如何根据其相对扩展不确定度大小来判定修正系数的意义。 相似文献
996.
通过分析光线通过微球壳层后各界面的相位分布,讨论了相移干涉法测量微球内表面粗糙度的基本原理,研究了微球上部壳层对内表面粗糙度测量的影响,得到了聚苯乙烯,聚a甲基苯乙烯微球的内表面形貌特征图像,测量数据与原子力显微镜测量数据在同一量级。以微球壳层对超光滑碳化硅及单晶硅片表面形貌的调制作用为研究对象,讨论了微球的外表面粗糙度以及微球壁厚对内表面粗糙度测量结果的影响,确定了相移干涉法测量微球内表面粗糙度的不确定度,实验结果表明:对于表面粗糙度小于30 nm、厚度小于9 mm的微球,测量不确定度小于0.4 nm。 相似文献
997.
János Pintér 《Annals of Operations Research》1991,31(1):527-544
In modelling and managing complex environmental systems, inherent uncertainties of all relevant natural processes are to be taken into consideration. In the present paper diverse stochastic modelling and optimization approaches for handling such problems (primarily in the field of water quality analysis and control) are highlighted, drawing on the findings of case studies and real-world applications. 相似文献
998.
Rudra P. Sarkar 《Proceedings Mathematical Sciences》2002,112(4):579-593
A theorem of Hardy characterizes the Gauss kernel (heat kernel of the Laplacian) on ℝ from estimates on the function and its
Fourier transform. In this article we establisha full group version of the theorem for SL2(ℝ) which can accommodate functions with arbitraryK-types. We also consider the ‘heat equation’ of the Casimir operator, which plays the role of the Laplacian for the group.
We show that despite the structural difference of the Casimir with the Laplacian on ℝn or the Laplace—Beltrami operator on the Riemannian symmetric spaces, it is possible to have a heat kernel. This heat kernel
for the full group can also be characterized by Hardy-like estimates. 相似文献
999.
On the specificity of a possibility distribution 总被引:4,自引:0,他引:4
Ronald R. Yager 《Fuzzy Sets and Systems》1992,50(3):279-292
The specificity of a possibility distribution measures the degree to which the distribution allows one and only one element as its manifestation. As such it is a measure of amount of uncertainty or information. We investigate a number of issues related to specificity measures. We discuss the connection between the specificity of a possibility distribution and the entropy of a probability distribution. We describe unifying view for constructing specificity measures. We look at the relationship of the specificity of a distribution and its negation. We consider the case where the base set is continuous. 相似文献
1000.
Yrjö Seppälä 《BIT Numerical Mathematics》1970,10(1):95-105
One objective in regional planning is the creation of communities with great accessibility. Thus we should plan the locations of inhabitants and the activities of the region so that the total accessibility will be maximized subject to some restrictions. This is a quadratic programming problem, which can be solved by quadratic programming techniques, but we cannot then take into account the uncertainties of the problem.In this paper a new criterion function is proposed for accessibility, uncertainty problems in regional land-use planning. It is derived from Hurwicz's generalized maximin principle. Many advantages are gained, for the planning problem is separated into linear programming problems, the uncertainties are taken into consideration as in game theory and the methods of parametric programming are available.A simplified problem of the populations of three town areas is studied and the method is generalized for problems of many activities and areas. 相似文献