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81.
82.
Energy dissipation of a ring-like metal rubber isolator   总被引:1,自引:0,他引:1       下载免费PDF全文
Metal rubber (MR) is a kind of homogeneous poroelastic damping material made of metal wire. In this paper, by ana- lyzing the forces on the MR isolator and the MR element, the hysteresis loops of the force and deformation are studied and verified by experiments. The results show that the force and displacement hysteresis loop of the MR isolator is described by the force and deformation hysteresis loops of the MR elements. In addition, the relationship between the energy dissipation coefficient of the MR element and that of the MR isolator is derived. The energy dissipation coefficient is programmed and calculated by MATLAB using experimental data, and the results are compared with the theoretical value. It is the basis for the design and applied research of the MR isolator in a future study.  相似文献   
83.
采用全量子理论,考虑了边界振动的微腔(振动边界视作频率为ωm的量子谐振子)与单模辐射场构成的系统,在薛定谔绘景中,给出了系统的时间演化算符,得到了系统的态函数随时间的演化关系.结果表明,当振动边界回到初态时的腔场态能给出许多与已有文献不同的薛定谔猫态,且通过调整单模辐射场的频率可以选择想要的薛定谔猫态.  相似文献   
84.
0 引言 玻璃态物质以纷繁多样的形式广泛存在于自然与科技技术领域[1-3].除了人们熟知的门窗上的硅酸盐无机玻璃、各种塑料制品的高聚物玻璃外,玻璃态还与光纤通讯、生物制品和生化药剂的保鲜存储、极端干燥条件下昆虫活性的保持等这些鲜为人知的方面密切相关.  相似文献   
85.
Most studies of the synthetic aperture radar remote sensing of ocean internal waves are based on the solitary wave solutions of the Korteweg-de Vries (KdV) equation, and the dissipative term in the KdV equation is not taken into account. However, the dissipative term is very important, both in the synthetic aperture radar images and in ocean models. In this paper, the traveling-wave structure to characterize the ocean internal wave phenomenon is modeled, the results of numerical experiments are advanced, and a theoretical hypothesis of the traveling wave to retrieve the ocean internal wave parameters in the synthetic aperture radar images is introduced.  相似文献   
86.
This paper demonstrates and analyses double heteroclinic tangency in a three-well potential model, which can produce three new types of bifurcations of basin boundaries including from smooth to Wada basin boundaries, from fractal to Wada basin boundaries in which no changes of accessible periodic orbits happen, and from Wada to Wada basin boundaries. In a model of mechanical oscillator, it shows that a Wada basin boundary can be smooth.  相似文献   
87.
俞阿龙 《中国物理 B》2008,17(3):878-882
This paper presents a method used to the numeral eddy current sensor modelling based on the genetic neural network to settle its nonlinear problem. The principle and algorithms of genetic neural network are introduced. In this method, the nonlinear model parameters of the numeral eddy current sensor are optimized by genetic neural network (GNN) according to measurement data. So the method remains both the global searching ability of genetic algorithm and the good local searching ability of neural network. The nonlinear model has the advantages of strong robustness, on-line modelling and high precision. The maximum nonlinearity error can be reduced to 0.037% by using GNN. However, the maximum nonlinearity error is 0.075% using the least square method.  相似文献   
88.
王珍  王志玺 《中国物理 B》2008,17(8):2790-2794
This paper obtains an entangled condition for isotropic-like states by using an atomic map. It constructs a class of bound entangled states from the entangled condition and shows that the partial transposition of the state from the constructed bound entangled class is an edge bound entangled state by using range criterion.  相似文献   
89.
刘时雄  刘劲松  蔡欣  樊婷  张光勇 《中国物理 B》2008,17(10):3771-3778
In a biased dissipative photovoltaic-photorefractive system, this paper investigates the temperature effect on the evolution and the self-deflection of the dissipative holographic screening-photovoltaic (DHSP) solitons. The results reveal that, the evolution and the self-deflection of the bright and dark DHSP solitons are influenced by the system temperature. At a given temperature, for a stable DHSP soliton originally formed in the dissipative system, it attempts to evolve into another DHSP soliton when the temperature change is appropriately small, whereas it will become unstable or break down if the temperature departure is large enough. Moreover, the self-deflection degree of the solitary beam centre increases as temperature rises in some range, while it is decided by the system parameters and is slight under small-signal condition. The system temperature can be adjusted to change the formation and the self-deflection of the solitary beam in order to gain certain optical ends. In a word, the system temperature plays a role for the DHSP solitons in the dissipative system.  相似文献   
90.
石云龙  陈鸿 《物理学报》1991,40(7):1162-1173
本文用变分法研究了耗散量子系统中的声于基态及其对局域一退局域相变条件的影响.发现: 1. 声子基态不仅存在通常的位移效应, 而且还有形变效应. 本文提出的位移一压缩态可同时描述这两种效应; 2. 声子基态的选择对相变条件有很大影响.随着声子基态能量下降,相变曲线将向强祸合方向移动. 关键词:  相似文献   
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