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61.
用连续输出100mw和脉冲输出200mW的国产双异质结激光二极管(DH-LD)泵浦Nd:YAG激光器,得到稳定的半导体激光泵浦的固体激光器连续输出12mW和10~50kHz重复频率的准连续输出,每个脉冲激光峰值功率20mW,起伏小于1%,与计算结果基本一致. 相似文献
62.
本文讨论了传统的应变式压力传感器检测电路,给出了改进措施,提高了视在输出,实现了零点调整,补偿了由于温度变化引起的受力弹性体的弹性系数变化和应变片灵敏度系数变化,满足了输出线性度要求。 相似文献
63.
64.
Enver Yücesan 《Annals of Operations Research》1994,53(1):471-484
The real utility of simulation lies in comparing different alternatives that might represent competing system designs. Conventional statistical techniques are not directly applicable to the analysis of simulation output data in the evaluation of competing alternatives since the usual assumptions of normality and common variance are difficult to justify in simulation experiments. This paper revisits a known nonparametric test whose application has recently become feasible due to considerable increases in computing power:randomization tests assess the significance of the observed value of the test statistic by evaluating different permutations of the data. The procedure only requires invariance of the data under all permutations. 相似文献
65.
Michiels Wim; Niculescu Silviu-Iulian; Moreau Luc 《IMA Journal of Mathematical Control and Information》2004,21(4):393-418
We address the output feedback stabilization problem of linearfinite-dimensional SISO systems. Limitations of static time-invariantoutput feedback on stabilizability are well known. We investigateand compare the possibilities of two recently proposed simplemodifications/generalizations of static time-invariant outputfeedback to remove such limitations. The first approach consistsof introducing a time-delay in the control law, which can betreated as an additional control parameter. The second approachconsists of making the gain time-varying. We show that bothapproaches are complementary. Existing theoretical results arebrought together in a unifying framework. Numerical proceduresfor the construction of the controllers are provided. Robustnessw.r.t. both parametric and delay uncertainty are dealt with.As an illustration the stabilizability of all second-order systemsis completely determined. 相似文献
66.
R. Scheps 《Optics & Laser Technology》1990,22(6):387-393
Using a model for the temporal and spatial variation of the saturation flux that considers the effects of temperature, fluorine burn-up and local E-fields on the quenching rates, it is found that long pulse operation of a KrF amplifier (τp > 500 ns) can result in spatial and temporal output irradiance uniformities greater than 80% across the aperture. Local E-fields are shown to be responsible for relatively large spatial saturation flux non-uniformities for short pulse KrF amplifier operation. 相似文献
67.
分析了两种比例运算电路在开环放大倍数Aod和差模输入电阻rid均为有限值时的闭环特性 ,导出了Avf,rif和rof的表达式 相似文献
68.
This work mainly addresses terminal constrained robust hybrid iterative learning model predictive control against time delay and uncertainties in a class of complex batch processes with input and output constraints. In this work, an equivalently novel extended two-dimensional switched system is first constructed to represent the process model by introducing state difference, output error and new relaxation variable information. Then, a hybrid predictive updating controller is proposed and an optimal performance index function including terminal constraints is designed. Under the condition that the switching signal meets certain conditions, the solvable problem of model predictive control is realized by Lyapunov stability theory. Meanwhile, the design scheme of controller parameters is also given. In addition, the robust constraint set is adopted to overcome the disadvantage that the traditional asymptotic stability cannot converge to the origin when it involves disturbances, such that the system state converges to the constraint set and meets its expected value. Finally, the effectiveness of the proposed algorithm is verified by controlling the speed and pressure parameters of the injection molding process. 相似文献
69.
数字滤波器在惯性测量装置中的应用 总被引:2,自引:2,他引:2
分析了数字电压表和数字示波器对惯性测量装置(IMU)模拟输出的测量数据,为了减少惯性测量装置模拟输出中的干扰信号对模数转换结果的影响,设计了数字巴特沃斯滤波器和中值平均滤波器。通过计算机仿真和实测说明:这两种数字滤波方法均可以在几乎不增加硬件的条件下提高IMU数字输出精度。 相似文献
70.
以微波为热源处理放射性废物的相关技术和装备的研究,在国外已经达到较高水平,在我国的相关研究较少。微波加热即物料在微波场中吸收消耗微波能量,并转化为热能用于物料温度升高。对于物料的处理效果主要与微波的有效输出功率有关。参考Schillman法测定了包括放射性废物微波处理装置的微波炉的有效输出功率,且经验证测定结果准确。微波有效输出功率的确定将对放射性废物微波处理工艺的研究打下基础。 相似文献