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41.
为了满足航天器桌面散态匹配试验测试需求,研制一种基于PC104总线的执行机构等效装置,详细阐述了等效装置的功能、工作原理、硬件电路设计、软件设计思想,该系统采用模块化、可配置软件架构设计,实现了正常、应急多测试工况一体化设计;应用严格的窗口比较器硬件电路设计技术,实现信号电压幅值的高精度采集,确保输入信号的可靠判定;利用FPGA技术突破信号脉宽高精度采集和信号延时高精度可控等关键技术,该系统实现了输入信号幅值、脉宽的实时采集、存储与显示,并按照事先设定的工作模式及配置参数,完成不同测试工况下输出信号的模拟反馈。试验结果表明,系统稳定可靠,人机界面友好,满足航天器多测试工况控制时序和功能检查需求。  相似文献   
42.
本文探讨了鞅分析在具有红利支付的n次幂型欧式期权定价中的应用,即用鞅分析的技巧与方法研究了在标的资产服从分数布朗运动的条件下具有红利支付的n次幂型欧式期权定价问题,并获得了其公式。丰富了已有期权定价结果,使期权定价公式更有利于实际的应用。  相似文献   
43.
In order to solve the torque design problem of deep lunar soil sampling using drilling, a novel torque analysis method was presented based on discrete element model (DEM). This method includes three stages: drilling simulation of the bit and stem segment, resultant torque calculation, and predicted curve fitting. First, special drilling models were designed for a bit and stem separately. A high-density equivalent particle group, boundary vibration control, pre-drilling simulation and constant pressure surface control were designed for the bit and stem drilling modelling at different depths to ensure the rationality of the model. An example of the torque synthesis process was given, and the simulation time was analyzed. Finally, the simulation predicted torque curve was plotted and compared with the experimental curve. The experimental and simulation curves show that as the drilling depth increases, the torque increases approximately linearly first and then flattens out gradually after a depth of 1 m. The consistency between the two results indicated that the proposed method was validated. Using this method, engineers can take short time to analyze the torque and design basic parameters of the drill mechanism. The problem of high experimental cost and long simulation time in torque design is solved.  相似文献   
44.
We apply the equivalence particle principle to several nonlinear Schrödinger equations (NLSEs) that model the propagation of a spatial beam with logarithmic law nonlinearity. Using this principle, expressions for acceleration, spatial frequency, spatial period and other variables for a spatial soliton can be derived from the solution of the homogenous NLSE with logarithmic law nonlinearity. These results agree well with numerical simulations of the perturbed NLSE. We show that if the expression of the acceleration is bounded this means the spatial soliton propagates with a swing effect.  相似文献   
45.
The equivalent circuit model of two-phase ionic conductors, introduced in Part I of this work, was applied to a set of xLi2O–B2O3 fast-ion conducting glasses, with x ranging from 3.0 to 4.5. The shape of Arrhenius plots, constructed by equivalent circuit fitting of impedance spectra measured at various temperatures, turned out to be in agreement with the predictions of the model. The analysis procedure, which was developed by mathematical investigation in accordance with the implications of the model, was employed to determine the activation energies of the two present phases and the total DC ionic resistivity of the examined glasses.  相似文献   
46.
本文用“剖面不变性”确定等效电子热导系数,研究了TCA装置上阿尔芬波加热的能量平衡,结果与实验符合很好。证明本文所用的方法对不同装置、不同加热方式都适用。  相似文献   
47.
一、引言 多年来,从事受控核聚变的研究人员相继对环形磁约束装置的硬X射线辐射做了许多深入的实验研究,因为逃逸电子是高温等离子体的必然产物,通过逃逸电子产物——硬X射线的研究,便可得知等离子体的行为。但是,装置的硬X射线辐射剂量却直接影响到周围环境及工作人员的身体健康。高能X射线通过物质时,主要以光电效应,康普顿散射和电子对效应损失能量,进入生物组织后,X射线能量在其中转移、吸收乃至最终导致组织损伤。随着实验的进展,人们对硬X射线辐射剂量日益关心。为此,1987年,我们在HL-1装置实验运行期间(近旁的电子回旋共振加热系统未投入工作),测量了装置的硬X射线辐射剂量。  相似文献   
48.
Let Гr,n—r denote the infimum of all number Г > 0 such that for any real indefinite quadratic form inn variables of type (r, n—r), determinantD ≠ 0 and real numbers c1; c2,…, cn, there exist integersx 1,x2,…,xn satisfying 0 < Q(x1+c1,x2 + c2,…,xn + cn) ≤(Г|Z > |)1/n. All the values of Гr,n—r are known except for г1,4. Earlier it was shown that 8 ≤Г1,4 ≤16. Here we improve the upper bound to get Г1,4 < 12.  相似文献   
49.
The generalized linear complementarity problem revisited   总被引:5,自引:0,他引:5  
Given a vertical block matrixA, we consider in this paper the generalized linear complementarity problem VLCP(q, A) introduced by Cottle and Dantzig. We formulate this problem as a linear complementarity problem with a square matrixM, a formulation which is different from a similar formulation given earlier by Lemke. Our formulation helps in extending many well-known results in linear complementarity to the generalized linear complementarity problem. We also show that the class of vertical block matrices which Cottle and Dantzig's algorithm can process is the same as the class of equivalent square matrices which Lemke's algorithm can process. We also present some degree-theoretic results on a vertical block matrix.  相似文献   
50.
A high power dynamic fundamental mode Nd:YAG laser is experimentally demonstrated with a stagger-pumped laser module and a V-shaped resonator. The rod is pumped symmetrically by staggered bar modules. And dynamic fundamental mode is achieved under different pump levels. The maximal continuous wave (CW) output of 124 W (M2=1.4) is achieved with a dual rod. Average output of 112 W, pulse width of 120 ns, pulse energy of 11.2 mJ and peak power of 93 kW are obtained in Q-switched operation of 10 kHz.  相似文献   
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