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991.
992.
Hui Li Feng Yang Hualong Du Hongping Hu Wei Jiang Xuedong Chen Yuantai Hu 《Acta Mechanica Solida Sinica》2009,22(5):499-509
The coupled extensional and flexural vibrations of an annular corrugated shell piezoelectric transducer consisting of multiple circularly-annular surfaces smoothly connected along the interfaces were investigated in the paper. Only a time-harmonic voltage is applied across two electrodes of the piezoelectric shell as the external loading. A theoretical solution was obtained using the classical shell theory. Based on the solution, basic vibration characteristics of resonant frequencies, mode shapes were calculated and examined. 相似文献
993.
ZHOU Li-Juan GU Yun-Ting MA Wei-Xing MENG Cheng-Ju PAN Ji-Huan 《理论物理通讯》2008,49(1):181-188
Based on the Global Color Symmetry Model, the non-perturbative Q, CD vacuum is investigated in the parameterized fully dressed quark propagator. Our theoretical predictions for various quantities characterized the QCD vacuum are in agreement with those predicted by many other phenomenologieal QCD inspired models. The successful predictions clearly indicate the extensive validity of our parameterized quark propagator used here. A detailed discussion on the arbitrariness in determining the integration cut-off parameter ofμ in calculating QCD vacuum condensates and a good method, which avoided the dependence of calculating results on the cut-off parameter is also strongly recommended to readers. 相似文献
994.
WANG Ling DONG Zhong-Zhou LIU Xi-Qiang 《理论物理通讯》2008,49(1):1-8
By applying a direct symmetry method, we get the symmetry of the asymmetric Nizhnik-Novikov-Veselov equation (ANNV). Taking the special case, we have a finite-dimensional symmetry. By using the equivalent vector of the symmetry, we construct an eight-dimensional symmetry algebra and get the optimal system of group-invariant solutions. To every case of the optimal system, we reduce the ANNV equation and obtain some solutions to the reduced equations. Furthermore, we find some new explicit solutions of the ANNV equation. At last, we give the conservation laws of the ANNV equation. 相似文献
995.
ZHANG Wen-Hai DAI Jie-Lin YE Liu 《理论物理通讯》2008,49(6):1473-1476
We propose an experimentally feasible scheme to implement the optimal asymmetric economical 1→2 phase-covariant quantum cloning in two dimensions based on the cavity QED technique. The protocol is very simple and only two atoms are required. Our scheme is insensitive to the cavity field states and cavity decay. During the processes, the cavity is only virtually excited and it thus greatly prolongs the efficient decoherent time. Therefore, it may be realized in experiment. 相似文献
996.
厉晓华 《浙江大学学报(理学版)》2009,36(5):545-548
特殊逻辑函数在电路设计中有着独特的优点.从特殊函数的定义出发,提出了检测舍任意项特殊逻辑函数的方法,并以实例加以说明.为超大规模集成电路中单元电路的设计与化简提供了新的方法,对进一步完善布尔代数系统具有一定的实际应用意义. 相似文献
997.
In the SU(3) simple group model, the new neutral gauge boson Z' couples to pairs of SM fermions with couplings fixed in terms of the SM gauge couplings and depending only on the choice of the fermion embedding. In this paper, we calculate the contributions of this new particle to the processes e^+e^-→l^+l^-, bb^-, and cc^- and study the possibility of detecting this new particle via these processes in the future high-energy linear e^+e^- collider(LC) experiments with √s= 500 GeV and £int= 340 fb^-1. We find that the new gauge boson Z' is most sensitive to the process e^+e^-→b^+b^-. As long as Mz,≤2 TeV , the absolute values of the relative correction parameter are larger than 5%. We calculate the forward-backward asymmetries and left-right asymmetries for the process e^+e^-→c^+c^-, with both the universal and anomaly-free fermion embeddings. Bounds on Z' masses are also estimated within 95% confidence level. 相似文献
998.
ZENG Xiao-Xiong HAN Yi-Wen YANG Shu-Zheng 《理论物理通讯》2009,51(1):187-189
Based on the covariant anomaly cancellation method, which is believed to be more refined than the initial approach of Robinson and Wilczek, we discuss Hawking radiation from the plane symmetric black hole. The result shows that Hawking radiation from the non-spherical symmetric black holes also can be derived from the viewpoint of anomaly. 相似文献
999.
Anirudh Pradhan 《理论物理通讯》2009,51(2):367-374
Some cylindrically symmetric inhomogeneous viscous fluid string cosmological models with magnetic field and cosmological term A varying with time are investigated. To get the deterministic solution, it has been assumed that the expansion (θ) in the model is proportional to the eigen value σ^11 of the shear tensor σ^ij. The value of cosmological constant for the model is found to be small and positive, which is supported by the results from recent supernovae Ia observations. The effect of bulk viscosity is to produce a change in perfect fluid and hence exhibits essential influence on the character of the solution. The physical and geometric properties of the models are also discussed in presence and absence of magnetic field. 相似文献
1000.
In this paper, we investigate symmetries of the new (4+1)-dimensional Fokas equation, including point symmetries and the potential symmetries. We firstly employ the algorithmic procedure of computing the point symmetries. And then we transform the Fokas equation into a potential system and gain the potential symmetries of Fokas equation. Finally, we use the obtained point symmetries wave solutions and other solutions of the Fokas equation. and some constructive methods to get some doubly periodic In particular, some solitary wave solutions are also given. 相似文献