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In this paper, we study a host-parasitoid model with Holling II Functional response, where we focus on a special case: the carrying capacity K2 for parasitoids is equal to a critical value
r 1η. It is shown that the model can undergo Bogdanov-Takens bifurcation. The approximate expressions for
saddle-node, Homoclinic and Hopf bifurcation curves are calculated. Numerical simulations, including bifurcation diagrams and corresponding phase portraits, are also given to illustrate the theoretical results. 相似文献
998.
Measurement Uncertainty and Its Connection to Quantum Coherence in an Inertial Unruh–DeWitt Detector
The dynamic characteristics of measured uncertainty and quantum coherence are explored for an inertial Unruh–DeWitt detector model in an expanding de Sitter space. Using the entropic uncertainty relation, the uncertainty of interest is correlated with the evolving time t, the energy level spacing δ, and the Hubble parameter H. The investigation shows that, for short time, a strong energy level spacing and small Hubble parameter can result in a relatively small uncertainty. The evolution of quantum coherence versus the evolving time and Hubble parameter, which varies almost inversely to that of the uncertainty, is then discussed, and the relationship between uncertainty and the coherence is explicitly derived. With respect to the l1 norm of coherence, it is found that the environment for the quantum system considered possesses a strong non-Markovian property. The dynamic behavior of coherence non-monotonously decreases with the growth of evolving time. The dynamic features of uncertainty and coherence in the expanding space with those in flat space are also compared. Furthermore, quantum weak measurement is utilized to effectively reduce the magnitude of uncertainty, which offers realistic and important support for quantum precision measurements during the undertaking of quantum tasks. 相似文献
999.
Vasilieva T. M. Vasiliev M. N. Garaeva V. V. Zlobin I. S. Mint Zaw Ye Htau Khin Maung Kyaw Htet Wai Yan Zaw Htet Ko Ko 《Russian Physics Journal》2020,62(11):2092-2100
Russian Physics Journal - Different schemes and designs of generators of low-temperature hybrid plasma produced by simultaneous ionization of plasma-generating medium by an electron beam with... 相似文献
1000.
Let be a cycle of order 4. Write for the maximum number of edges in a balanced 3‐partite graph whose vertex set consists of three parts, each has vertices that have no subgraph isomorphic to . In this paper, we show that , where and is a prime number. Note that from Tait and Timmons's works. Since for every integer , one can find a prime such that , we obtain that . 相似文献