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111.
By developing multiple-scale method combined with
Wentzel--Kramer--Brillouin expansion, this paper analytically
studies the modulating effect of weakly periodic potential on the
dynamical properties of the Bose--Einstein condensates (BEC) trapped
in harmonic magnetic traps. A black--grey soliton transition is
observed in the BEC trapped in harmonic magnetic potential, due to
the weakly periodic potential modulating effect. Meanwhile, it finds
that with the slight increase of the weakly periodic potential
strength, the velocity of the soliton decreases, while its width
firstly decreases then increases, a minimum exists there. These
results show that the amplitude, velocity, and width of matter
solitons can be effectively managed by means of a weakly periodic
potential. 相似文献
112.
113.
A scheme is proposed to controll the decoherence of
three-level rf-SQUID qubit with asymmetric potential by designing an
external electric circuit for superconductive flux qubit. The
results show that it may not only raise the gate speed but also extend
decoherence time for a three-level structure. 相似文献
114.
115.
In this paper,a dedicated synchrotron radiation (SR) mode for the BEPCⅡ with an emittance of 85 nm has been designed,including the linear lattice,chromaticity correction and dynamic aperture optimization.The emittance of the new mode is about 60% of the previous mode used for routine operation of the BEPCⅡ .The effect of wigglers on the linear lattice was compensated and the total dynamic aperture including the wigglers’ nonlinear effect was estimated.The preliminary commissioning at the end of 2008 and the formal operation with the new mode confirmed its merits. 相似文献
116.
Temporal electronic structure of non-resonant Raman excited virtual state of P-nitroaniline by 514 nm excitation via bond polarisabilities 下载免费PDF全文
We have studied the temporal bond polarisabilities of para-nitroaniline from the Raman intensities by the algorithm proposed by Wu et al.in 1987 (Tian B,Wu G,Liu G 1987 J.Chem.Phys.87 7300).The bond polarisabilities provide much information concerning the electronic structure of the non-resonant Raman excited virtual state.At the initial moment by the 514.5 nm excitation,the tendency of the excited electrons (mapped out by the bond polarisabilities) is to spread to the molecular periphery,and the electronic structure of the Raman virtual state is close to the pseudo-quinonoidic state.When the final stage of relaxation is approached,the bond polarisabilities of those peripheral bonds relax faster than those closer to the molecular core,the phenyl ring.The molecule is in the benzenoidic form as demonstrated by the bond polarisabilities after relaxation. 相似文献
117.
A Continuous-Wave Ho:YA103 Laser with Output 8.5 W Pumped by a 1.91μm Laser at Room Temperature 下载免费PDF全文
A cw high efficient Ho:YAI03 laser pumped by 1.91 μm diode-pumped Tm:YLF laser at room temperature is realized. The maximum output power reaches 8.5 W when the incident pump power is 15.6 W. The slope efficiency is 63.7%, and the Tm:YLF to Ho:YAP optical conversion efficiency is 54.5%. The laser wavelength is 2118.3nm when the transmission of output coupler is 30%. The beam quality factor is M2 -1.39 measured by the traveling knife-edge method. 相似文献
118.
基于北斗/iNEMO惯性模块研究了一种组合式机器人运动姿态测量系统和解算方法。设计了以ARM为核心的嵌入式组合姿态解算平台,通过四元数法和卡尔曼滤波技术,对iNEMO惯性组件测量数据进行融合,进而在高动态环境中实时解算出机器人的运动姿态。同时,以北斗接收机输出的1PPS上升沿脉冲作为数据融合的同步信号,并利用其输出的导航信息辅助iNEMO惯性模块实现精对准。测试结果验证了设计方案的可行性和正确性,为机器人姿态解算提供了一种高精度、高稳定性、小体积、低功耗的解决方案。 相似文献
119.
软体驱动器是构建智能软体机器人的基石。然而,由于软体驱动器具有非线性、耦合和不确定性等复杂的特性,如何对其进行有效建模与控制是目前极需解决的难题。以一种由三支单腔双向弯曲软驱动器构成的软体微手为研究对象,对其进行了鲁棒非线性控制设计研究。首先,进行了鲁棒非线性控制系统的总体结构设计分析。其次,对如何设计算子控制器、跟踪控制器、算子观测器实现其对软体微手的弯曲角度和力进行控制进行了分析和讨论。接着,分析和研究了鲁棒稳定和跟踪条件。最后,通过基于实验数据的仿真验证了所提方案的可行性和有效性。 相似文献
120.
We report a high power and high efficiency double resonant ZnGeP2 (ZGP) optical parametric oscillator (OPO) pumped by a Tm,Ho:GdVO4 laser. We employ a Tm,Ho:GdVO4 laser as the pump source operated at 2.049 μm with M^2 = 1.1. The ZGP OPO can generate a total combined output power of 14.1 W at 3.80μm signal and 4.45 μm idler under pumping power of 28. 7 W. The slope efficiency reaches 61.8%, and M^2 = 3.6 for OPO output is obtained. 相似文献