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101.
该文用微分几何方法对AR(q)误差非线性回归模型若干二 阶渐近性质进行了研究. 作者基于Fisher信息阵在欧氏空间定义了内积,并在期望参数空间建立了几何结构. 基于上述几何结构,给出了AR(q)误差非线性回归模型若干二阶渐近性质的曲率表示. 将前人的一些结果推广到AR(q)误差非线性回归模型. 相似文献
102.
利用q-超球多项式的两个简单性质,建立了关于q-级数的两个变换公式,借助这些变换公式并结合著名的Rogers-Ramanujan恒等式,给出了若干Rogers-Ramanujan型恒等式的简洁证明。 相似文献
103.
Neuraminidase is a significant anti‐influenza target that plays crucial role in virus replication cycle. The discovery of 150‐cavity in Group‐1 neuraminidase provides us a novel mentality of designing inhibitor which can bind with both conserved site and 150‐cavity. In order to discover novel dual‐site‐binding inhibitors, a 3D chemical‐feature‐based pharmacophore model was established to cover dual‐site in neuraminidase. The dual‐site‐binding model was consistent in predicting the binding conformation of Group‐1 neuraminidase inhibitor and applied for virtual screening of Specs database. Compound 4 (ZINC05790048) that aligned well to the model was selected after multiple filtrations for molecular dynamics simulations, indicating improved binding energy with neuraminidase. It can sever as the lead compound for a novel series of inhibitors. 相似文献
104.
We consider the effect of a variable representing the competition between the frequency of the field and the frequency of the spin flipping (Ω) on the dynamics of the metamagnetic Ising model in a cubic lattice under the presence of a time varying (oscillating) external magnetic field. The system is modelled with a formalism of master equation at a mean-field level. The time averaged staggered magnetization (Ms) acts as the order parameter and divides temperature field plane into three regions: anti-ferromagnetic, paramagnetic and coexistence of anti-ferromagnetic and paramagnetic phases. It is observed that the topology of the dynamical phase diagram depends strongly on Ω as well as the ratio between interlayer and intralayer couplings. 相似文献
105.
E.B. Fel'dman 《Physics letters. A》2009,373(20):1719-1728
This Letter concerns the problem of the high probability state transfer among s2 symmetrically placed nodes of the N-node chain of spins 1/2 with the XXZ Hamiltonian. We consider examples with (N,s)=(4,4), (N,s)=(6,4) and (N,s)=(8,8). 相似文献
106.
N. G. Fytas A. Malakis 《The European Physical Journal B - Condensed Matter and Complex Systems》2008,61(1):111-120
The one-parametric Wang-Landau (WL) method is
implemented together with an extrapolation scheme to yield
approximations of the two-dimensional (exchange-energy,
field-energy) density of states (DOS) of the 3D bimodal
random-field Ising model (RFIM). The present approach generalizes
our earlier WL implementations, by handling the final stage of the
WL process as an entropic sampling scheme, appropriate for the
recording of the required two-parametric histograms. We test the
accuracy of the proposed extrapolation scheme and then apply it to
study the size-shift behavior of the phase diagram of the 3D
bimodal RFIM. We present a finite-size converging approach and a
well-behaved sequence of estimates for the critical disorder
strength. Their asymptotic shift-behavior yields the critical
disorder strength and the associated correlation length's
exponent, in agreement with previous estimates from ground-state
studies of the model. 相似文献
107.
We study a stochastic model of an economy with locally interacting agents. The basis of the study is a deterministic model of dynamic economic equilibrium proposed by Polterovich. We generalize Polterovich's theory, in particular, in two respects. We introduce stochastics and consider a version of the model with local interactions between the agents. The structure of the interactions is described in terms of random fields on a directed graph. Equilibrium states of the system are solutions to certain variational inequalities in spaces of random vectors. By analyzing these inequalities, we establish an existence theorem for equilibrium, which generalizes and refines a number of previous results. 相似文献
108.
N. B. Éshkobilov 《Journal of Applied Spectroscopy》2002,69(3):477-479
The main series of a silver atom with n = 5–70 are investigated. Perturbations of the np
2
P
1/2,3/2 states with n = 10 and 17 caused by interaction with the selfionization 4d5s5p
4
P
1/2,3/2 states are detected. Energies of the selfionization states are determined. 相似文献
109.
The structure and optical properties of the films of ternary compounds AgInSe2, CuInSe2 and Cu
x
Ag1–x
InSe2 solid solutions obtained by pulsed laser evaporation are investigated. It has been established that the films like bulk crystals have the structure of chalcopyrite. By the transmission and reflection spectra near the edge of natural absorption the refractive index and coefficient of optical absorption are calculated and the energies of interband transitions and the crystalline and spinorbit splitting are determined. 相似文献
110.
Roman Frič 《Czechoslovak Mathematical Journal》2002,52(4):861-874
We show that each sequentially continuous (with respect to the pointwise convergence) normed measure on a bold algebra of fuzzy sets (Archimedean MV-algebra) can be uniquely extended to a sequentially continuous measure on the generated ukasiewicz tribe and, in a natural way, the extension is maximal. We prove that for normed measures on ukasiewicz tribes monotone (sequential) continuity implies sequential continuity, hence the assumption of sequential continuity is not restrictive. This yields a characterization of the ukasiewicz tribes as bold algebras absolutely sequentially closed with respect to the extension of probabilities. The result generalizes the relationship between fields of sets and the generated -fields discovered by J. Novák. We introduce the category of bold algebras and sequentially continuous homomorphisms and prove that ukasiewicz tribes form an epireflective subcategory. The restriction to fields of sets yields the epireflective subcategory of -fields of sets. 相似文献