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11.
A weakly nonlinear theory of wave propagation in two superposed dielectric fluids in the presence of a horizontal electric field is investigated in (2+1)-dimensions. The equation governing the evolution of the amplitude of the progressive waves is obtained in the form of a two-dimensional nonlinear Schrödinger equation. A three-wave resonant interaction for nonlinear excitations created from electrohydrodynamic capillary-gravity waves is observed to be possible in a dispersive medium with a self-focusing cubic nonlinearity. Under suitable conditions, the nonlinear envelope equations for the resonant interaction are derived by using multiple scales and inverse scattering methods, and an explicit three-wave soliton solution is discussed. Both the dynamic properties and the modulational instability of finite amplitude electrohydrodynamic wave are studied for the cubic nonlinear Schrödinger equation by means of linearized stability analysis and the nonlinear interaction coefficient. We show that the trajectories in phase space exhibit different behavior with the increase of nonlinear perturbations, and we determine the electric field and wavenumber ranges at which the original point is elliptic or hyperbolic, respectively. It is found also that the presence of the electric field in the equation modifies the nature of wave stability and soliton structures, and that the amplitude and width of the soliton are decreased and increased, respectively, when the electric field value increases.  相似文献   
12.
本文通过论述798艺术区的历史沿革、798的文化概念以及发展趋势,让人们感受到这是一个活生生的工厂,同时也是一个生机勃勃的艺术区;而艺术展览的宣传海报,画廊、工作室的指示标牌,引人注目的雕塑作品,时髦的青年和穿梭往来的外国游客,一切又构成了极强的艺术和时尚氛围。少时记忆中的工厂环境与奇思幻想的艺术构思的组合,让人有种时空交错的感觉。  相似文献   
13.
While the internet has a lot of positive impact on society, there are negative components. Accessible to everyone through online platforms, pornography is, inducing psychological and health related issues among people of all ages. While a difficult task, detecting pornography can be the important step in determining the porn and adult content in a video. In this paper, an architecture is proposed which yielded high scores for both training and testing. This dataset was produced from 190 videos, yielding more than 19 h of videos. The main sources for the content were from YouTube, movies, torrent, and websites that hosts both pornographic and non-pornographic contents. The videos were from different ethnicities and skin color which ensures the models can detect any kind of video. A VGG16, Inception V3 and Resnet 50 models were initially trained to detect these pornographic images but failed to achieve a high testing accuracy with accuracies of 0.49, 0.49 and 0.78 respectively. Finally, utilizing transfer learning, a convolutional neural network was designed and yielded an accuracy of 0.98.  相似文献   
14.
The p--T relationships have been measured for 1,1-difluoroethane (R152a) and 1,1,1-trifluoroethane (R143a) by an isochoric method with gravimetric determinations of the amount of substance. Temperatures ranged from 158 to 400 K for R152a and from 166 to 400 K for R143a, while pressures were up to 35 MPa. Measurements were conducted on compressed liquid samples. Determinations of saturated liquid densities were made by extrapolating each isochore to the vapor pressure, and determining the temperature and density at the intersection. Published p--T data are in good agreement with this study. For the p--T apparatus, the uncertainty of the temperature is ±0.03 K, and for pressure it is ±0.01% at p>3 MPa and ±0.05% at p<3 MPa. The principal source of uncertainty is the cell volume (28.5 cm3), which has a standard uncertainty of ±0.003 cm3. When all components of experimental uncertainty are considered, the expanded relative uncertainty (with a coverage factor k=2 and thus a two-standard deviation estimate) of the density measurements is estimated to be ±0.05%.  相似文献   
15.
提出了一种以PIC16F884单片机为控制单元,以两台塑壳断路器双电源开关为控制对象的智能控制器的设计方案.介绍了控制器的工作原理和工作模式,并给出了硬件方案和软件设计思想以及抗干扰的方法.  相似文献   
16.
A stochastic differential equation involving both a Wiener process and fractional Brownian motion, with nonhomogeneous coefficients and random initial condition, is considered. The coefficients and initial condition depend on a parameter. The assumptions on the coefficients and the initial condition supplying continuous dependence of the solution on a parameter, with respect to the Besov space norm, are established.  相似文献   
17.
In this paper, we investigate an inexact hybrid projection-proximal method for solving a class of generalized mixed variational inequalities in Hilbert spaces. We construct a general inexact hybrid projection-proximal point algorithm, in which an inexact relaxed proximal point step is followed by a suitable orthogonal projection onto a hyperplane. Under some suitable conditions concerned with the pseudomonotone set-valued mapping T, the nonsmooth convex function f and the step size λk, we prove the convergence of the inexact hybrid projection-proximal point algorithm for solving generalized mixed variational inequalities in Hilbert spaces.  相似文献   
18.
研究了日本N4样机的电动助力转向系统的电机电流-输入扭矩特性.采用ATmega16L单片机为处理器,以直流有刷电机为执行器,应用PID补偿算法,设计了电动助力转向控制器.在试验台上进行了电机电流-输入扭矩特性试验,试验结果表明,该控制器的助力曲线接近日本N4样机,能取得比较满意的助力效果.  相似文献   
19.
The main aims of this study are to derive the fuzzy Euler-Lagrange conditions for both fuzzy unconstrained and constrained variational problems based on the concepts of differentiability and integrability of a fuzzy mapping that may be parameterized by the left and right-hand functions of its α-level sets.  相似文献   
20.
We investigate asymptotic behavior of the C0-semigroup T(t) associated with the mono-tubular heat exchanger equation with output feedback by a perturbation method. It is shown that T(t) is bounded if a constraint is satisfied by the parameters and the spatial distribution function. Further, applying the Arendt-Batty-Lyubich-Vu theorem, a criterion is established to judge strong stability of T(t).  相似文献   
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