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171.
以国家统计局统计科学研究所制定的全面建设小康指标体系为基础,采用变异系数法确定权重,构建我国全面建成小康社会指标体系,测算了我国2007-2012年全面建成小康社会的实现程度,测算结果表明2012年我国全面建成小康社会实现程度达84.9%.与此同时,利用一次线性预测模型、对数曲线预测模型和灰色预测模型构建变权重组合预测模型对2013-2020年我国全面建成小康社会实现程度进行预测,预测结果表明我国将在2019年实现全面建成小康社会的目标. 相似文献
172.
Najeeb Alam Khan Muhammad Ali Qureshi Tooba Hameed Saeed Akbar Saif Ullah 《理论物理通讯》2020,72(12):125004-70
In this paper, we propose an innovative chaotic system, combining fractional derivative and sine-hyperbolic nonlinearity with circuit execution. The study of this system is conducted via an analog circuit simulator, using two anti-parallel semiconductor diodes to provide hyperbolic sine nonlinearity, and to function as operational amplifiers. The multi-stability of the system is also enhanced with the help of multi-equilibrium points for distinct real orders of system. The system explores the generation of a four-wing attractor in different phases, both numerically and electronically. By changing the input parameters of the system, different graphs are generated for current flow in state, phase, and space, to confirm the precision of the fractional order derivatives. A reasonable simulation shows that the deliberate circuit provides effective chaos in terms of speed and accuracy, which is comensurate with the numerical simulation. This nonlinear chaotic behavior is utilized to encrypt sound (.wav), images (.jpg), and animated (.gif) data which are a major requirement for the security of communication systems. The proposed circuit performs chaos and cryptographic tasks with high-effective analog computation, and constitutes a novel approach to this area of research. 相似文献
173.
Boundary operators and boundary ground states in sine-Gordon model with a fixed boundary condition are studied using bosonization and q-deformed oscillators. We also study the boundary bound state for this case. 相似文献
174.
We derive a free boson representation of the Yangian double
DYħ(slN)
with arbitrary level k by the observation that there is a correspondence between the q-affine algebra and Yangian double associated with the same Cartan matrix. Vertex operator and screening currents cannot be obtained in the same way. From this point of view, the Yangian double with
centre cannot be regarded as the degenerated case of the
quantum affine algebra. 相似文献
175.
Dong Ruan 《Journal of mathematical chemistry》2006,39(2):417-440
In this paper two kinds of two-boson realizations of the polynomial angular momentum algebra are obtained by generalizing
the well known Jordan–Schwinger realizations of the SU(2) and SU(1,1) algebras. Especially, for the Higgs algebra, an unitary
realization and two nonunitary realizations, together with the properties of their respective acting spaces are discussed
in detail. Furthermore, similarity transformations, which connect the nonunitary realizations with the unitary ones, are gained
by solving the corresponding unitarization equations. As applications, the dynamical symmetry of the Kepler system in a two-dimensional
curved space is studied and phase operators of the Higgs algebra are constructed. 相似文献
176.
It is well known that the bosonized version of the Wakimoto construction allows the explicit realization of any affine algebra
, with arbitrary level k in the homogeneous gradation, in terms of dim
free bosonic fields.However, its extension in the principal gradation has been achieved only in the simplest case k=1. In this Letter we show, in the case of the simplest affine algebra
,that the bosonized Wakimoto realization can be extended to the principal gradation only when k is equal to the critical level, i.e., –2.In this case, this construction can be achieved in terms ofarbitrary number (larger than 1) of free bosonic fields. 相似文献
177.
In this paper, we mainly investigate the realization of 3-Lie algebras from a family of Lie algebras. We prove the realization theorem, offer a concrete example realizing all type of 4-dimensional 3-Lie algebras, and also give some properties about semi-simple n-Lie algebras. 相似文献
178.
讨论了极大代数上线性系统的3维最小实现问题.给出了特征方程为λ~3⊕c_0λ~0=c_2λ~2⊕c_1λ的一类无穷序列{gi}_0~∞存在3维最小实现的充要条件,彻底解决了存在3维最小实现的充要条件问题. 相似文献
179.
采用高速DSP芯片TMS320F2812和USB2.0接口芯片CY7C68001来解决激光雕刻切割机控制系统数据传输中的低速问题。介绍了系统的硬件连接及软件实现。通过实际测试证明,USB2.0接口的实际数据传输速度最高可达200Mbps,完全可以满足激光雕刻切割机控制系统高速、实时传输的要求;同时利用USB总线对整个系统进行了有效地扩展。 相似文献
180.
《Wave Motion》2015
An array is constructed to radiate the far-field pattern of a single complex point source. For any nonzero error tolerance, the physical dimension of the array is smaller (sometimes much smaller) than the diameter of the branch-cut disk of the complex point source. The inverse source problem is formulated for non-resonant arrays with reactive zones that do not extend significantly beyond the physical dimensions of the array. Both time-harmonic and pulsed beams are considered. In numerical examples, each array element consists of real point sources in an end-fire configuration. 相似文献