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61.
62.
A newly designed cylindrical optical micro-rotator which has slopes for trapping and rotation on its upper surface is proposed. The cylindrical shape is effective in decreasing viscous drag force (damping factor) in the medium. A ray-tracing method considering the beam waist is employed to analyze the radiation pressure exerted on the upper surface of the rotator. We have demonstrated optical trapping and high speed rotation for various optical beam parameters such as the lens numerical aperture and the Gaussian mode profile as well as rotator shape parameters including oblique angle, height and diameter. 相似文献
63.
64.
DENG Guifeng ZHU Deming 《数学年刊A辑(中文版)》2007,(5)
对余维3系统X_μ(x)具有包含一个双曲鞍-焦点O_1和一个非双曲鞍-焦点O_2的异宿环f进行了研究.证明了在f的邻域内有可数无穷条周期轨线和异宿轨线,当非粗糙异宿轨线Γ~0破裂时X_μ(x)会产生同宿轨分支,并给出了相应的分支曲线和两种同宿环共存的参数值.在3参数扰动下Γ~0破裂和O_2点产生Hopf分支的情况下,在f的邻域内有一条含O_1点同宿环,可数无效多条的轨线同宿于O_2点分支出的闭轨H_0,一条或无穷多条(可数或连续统的)异宿轨线等. 相似文献
65.
The J_2-integral induced from the interface of bimaterial solids(J_2~(interface))is stud-ied by numerical method.First,the effect on the J_2-integral induced from the interface is verysignificant in bimaterial solids,which is inherently related to that induced from the subinterfacecracks.Moreover,it can be concluded that either the first or the second component of the J_k-vector is always equal to zero when the contour encloses both the cracks and the whole interfacein bimaterial solids.Secondly,it can also be concluded that the interface does produce significanteffect on the J_2-integral induced from the subinterface cracks(J_2~(sub))in bimaterial solids.Thiseffect depends on the geometry of the crack arrangement,which is corresponding to the differentinteraction effect among the cracks and the interface.Moreover,the interface effect on the J_2~(sub)can be neglected when the distance from the crack center to the interface is large enough,whichreveals that the bimaterial solids can be regarded as homogenous solids in fracture analysis whenthe subinterface crack is far enough from the interface.Three examples are given in this paper. 相似文献
66.
67.
K. D. Danov R. Aust F. Durst U. Lange 《International Journal of Multiphase Flow》1995,21(6):1169-1189
In order to investigate the hydrodynamic interaction between an interface and a spherical particle and its dependence on the type of interface, it is essential to compute the drag and torque exerted on the sphere in the vicinity of the interface. In this paper, the problem of all slow elementary motions (relative translation and rotation) and stationary movement of a spherical particle next to a solid, viscous or free interface is considered. For low capillary numbers and different values of surface dilatational and shear viscosities in a curvilinear co-ordinate system of revolution with bicylindrical co-ordinates in meridian planes, the problem reduces from three to two dimensions. The model equations and boundary conditions, which contain second-order derivatives of the velocities, transform to an equivalent well-defined system of second-order partial differential equations which is solved numerically for medium and small values of the dimensionless distance to the interface. Very good agreement with the asymptotic equation for a translating sphere close to a solid interface could be achieved. The numerical results reveal in all cases the strong influence of the surface viscosity on the motion of the solid sphere. For small distances from the interface, the drag and torque coefficients change significantly depending on the surface viscosity. 相似文献
68.
In order to achieve a higher lateral resolution required for ultraprecision measurement of microstructural workpieces, phase-only pupil filtering differential confocal microscopy (PFDCM), a new approach is proposed based on the differential confocal microscopy (DCM), which uses a three-zone phase-only pupil filter with lateral super-resolution capability obtained through optimized design to change the distribution of DCM three-dimensional point spread function, so that the DCM lateral resolution is therefore significantly improved while its axial resolution is slightly improved. Preliminary experimental comparison and analyses indicate that, the lateral and axial resolutions of PFDCM are better than 0.2 μm and 2 nm, respectively, when wavelength of incidence laser beam , numerical aperture of measuring lens NA=0.85, and lateral spot size with a three-zone phase-only pupil filter GT=0.65. It is therefore concluded that PFDCM is a new approach to further improvement of lateral resolution in laser probe measurement systems. 相似文献
69.
微力矩导弹舵机负载模拟器的理论研究 总被引:1,自引:0,他引:1
以某型号反坦克导弹舵机为对象,对一种称之为微力矩负载模拟器进行了研究。根据该型号导弹舵机的特点,对系统关键元件的选择设计进行了分析,建立了系统的数学模型,并通过分析多余力矩的产生机理,对系统进行了多余力矩补偿和校正,最后进行了仿真分析。 相似文献
70.
本文详细介绍了基于电磁涡流比拟理论运用微电脑和辅助机构,研究制造的抗扭刚度自动测定仪的基本原理,系统的误差分析等。对工程轴类以及几种特殊面杆件的抗扭刚度进行了测试研究。 相似文献