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81.
Some Results behind Dividend Problems 总被引:1,自引:0,他引:1
Ming Zhou Li Wei Jun-yi Guo 《应用数学学报(英文版)》2006,22(4):681-686
We consider the basic dividend problem of the compound Poisson model with constant barrierstrategy.Some results concealed behind the dividend problem are made explicit in the present work.Differentmethods and some of which are firstly given in this paper.All these results presented certain direct relationshipbetween some important actuary variables in classical risk theory is also revealed. 相似文献
82.
83.
Influence of buffer layer thickness on the structure and optical properties of ZnO thin films 总被引:1,自引:0,他引:1
A series of ZnO thin films were deposited on ZnO buffer layers by DC reactive magnetron sputtering. The buffer layer thickness determination of microstructure and optical properties of ZnO films was investigated by X-ray diffraction (XRD), photoluminescence (PL), optical transmittance and absorption measurements. XRD results revealed that the stress of ZnO thin films varied with the buffer layer thickness. With the increase of buffer layer thickness, the band gap edge shifted toward longer wavelength. The near-band-edge (NBE) emission intensity of ZnO films deposited on ZnO buffer layer also varied with the increase of thickness due to the spatial confinement increasing the Coulomb interaction between electrons and holes. The PL measurement showed that the optimum thickness of the ZnO buffer layer was around 12 nm. 相似文献
84.
在平均场理论架构下, 以含时金兹堡-朗道和Glauber动力学这两类动态模型为基础,研究 了受外场和温度共同驱动的Ising自旋体系的非平衡动态相变.确定了界定动态无序(动态顺 磁相P)和动态有序(动态铁磁相F)转变的动态相界.并根据动态序参量Q和Binder参数U随系统 温度t(r0)、驱动外场频率ω和振幅h0的变化规律,就上述两类模 型的动态相界上是否存在区分连续动态转变和非连续动态转变的三临界点这一引发争议的问 题做出了进一步分析说明.
关键词:
Ising自旋体系
非平衡动态相变
含时金兹堡-朗道模型
Glauber 动力学模型 相似文献
85.
本文在M ogens B ladt和T ina H av iid R ydberg无市场假设,仅利用价格过程的实际概率的期权保险精算定价模型的基础上,得出了标的资产服从几何分数布朗运动的欧式期权定价公式,并说明了几何布朗运动是本文的一种特殊情况. 相似文献
86.
几种陆用惯性自寻北方案的比较 总被引:2,自引:1,他引:1
介绍几种目前广泛应用于军事及民用工业领域的高精度自寻北方案,同时讨论并分析了这些方案的精度和误差补偿方法,提出在兵器领域尤其是在陆用车辆上的适用性等问题。 相似文献
87.
Summary Glass formation in nature and materials science is reviewed and the recent recognition of polymorphism within the glassy state,
polyamorphism, is discussed. The process by which the glassy state originates during the continuous cooling or viscous slowdown
process, is examined and the three canonical characteristics of relaxing liquids are correlated through the fragility. The
conversion of strong liquids to fragile liquids by pressure-induced coordination number increases is discussed, and then it
is shown that for the same type of system it is possible to have the same conversion accomplished via a first-order transition
within the liquid state. The systems in which this can happen are of the same type which exhibit polyamorphism, and the whole
phenomenology can be accounted for by a recent simple modification of the van der Waals model for tetrahedrally bonded liquids.
The concept of complex amorphous systems which can lose a significant number of degrees of freedom through weak first-order
transitions is then used to discuss the relation between native and denatured hydrated proteins, since the latter have much
in common with plasticized chain polymer systems. Finally, we close the circle by taking a short-time-scale phenomenon given
much attention by protein physicists,viz., the onset of an anomaly in the Debye-Waller factor with increasing temperature, and showing that for a wide variety of liquids,
including computer-simulated strong and fragile ionic liquids, this phenomenon is closely correlated with the experimental
glass transition temperature. This implies that the latter owes its origin to the onset of strong anharmonicity in certain
components of the vibrational density of states (evidently related to the boson peak) which then permits the system to gain
access to its configurational degrees of freedom. The more anharmonic these vibrational components, the closer to the Kauzmann
temperature will commence the exploration of configuration space and, for a given configurational microstate degeneracy, the
more fragile the liquid will be.
Paper presented at the I International Conference on Scaling Concepts and Complex Fluids, Copanello, Italy, July 4–8, 1994. 相似文献
88.
Optical properties and microstructure of Ag film on glass substrate with Cr intermediate layer were studied by using spectrophotometer and XRD. The spectra results showed that introducing Cr intermediate layer reduced the surface roughness and promoted the reflectivity of Ag film. The XRD analysis showed that the crystalline grains increased and the stress decreased. The adhesion was also improved by using the tape test method. 相似文献
89.
90.
The effect of γ-ray irradiation on the magnetic properties of NdFeB and Fe–Cr–Co permanent magnets has been investigated. The magnetic flux loss of two kinds of magnets before and after irradiation was measured. Results show that the effect of γ-ray irradiation on the magnetic properties of sintered NdFeB is not so obvious as that on Fe–Cr–Co magnet. Irradiation-induced damage from γ-ray for the Fe–Cr–Co magnets was characterized for the first time. The decline of permanent magnetic properties of Fe–Cr–Co magnet induced by γ-ray irradiation is reversible except for the maximum energy product (BH)max. The difference of coercivity mechanism between these two kinds of permanent magnets is responsible for the different dependence of magnetic properties loss induced by γ-ray irradiation. 相似文献