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31.
In this paper, the tristable stochastic resonance (SR) phenomenon induced by \(\alpha \)-stable noise is analysed. The mechanism for realizing resonance is explored based on research concerning the potential function and resonant output of a system. The rules for resonance system parameters q, p, skewness parameter r and intensity amplification factor Q of \(\alpha \)-stable noise to act on the resonant output are explored under different values of stability index \(\alpha \) and asymmetric skewness \(\beta \) of \(\alpha \)-stable noise. The results will contribute to a reasonable selection of parameter-induced tristable SR system parameters under \(\alpha \)-stable noise, and lay the foundation for a practical engineering application of weak signal detection based on the SR. 相似文献
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三角插值中的线性求和问题 总被引:5,自引:0,他引:5
本文通过选取求和因子构造出和式型三角插值多项式Hn(f,r,x)(r为奇自然数),使其在全实轴上一致地收敛到以2π为周期的连续函数f(x),且Hn(f,r,x)对Cn2π(l≤r)连续函数类的逼近均达到最佳收敛阶.Hn(f,r,x)的饱和阶为1/n(r+1),饱和函数类为f(r)(x)∈Lipml. 相似文献
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Zhenxu?Bai Yulei?Wang Zhiwei?LuEmail author Yi?Chen Sensen?Li Hang?Yuan Zhaohong?Liu Tan?Tan Can?Cui Hongli?Wang 《Journal of Russian Laser Research》2016,37(4):382-388
We present an efficient and compact passively Q-switched flash-lamp-pumped Nd:Ce:YAG singlelongitudinal-mode (SLM) laser system. With Cr4+:YAG as a saturable absorber, we design a three-plan resonant reflector for generating smooth SLM Q-switched pulses. We provide a theoretical calculation and optimization of the resonant reflector for improving the longitudinal-mode selection ability. We obtain a stable SLM output with a single-pulse energy of 10 mJ and a pulse width of 10.7 ns at 10 Hz. The near-diffraction-limited beam-quality parameter M2 is less than 1.5. The system can operate with a repetition rate from 1 to 10 Hz. We achieve the stable laser operation with less than 3% fluctuation of the pulse energy within 10,000 shots. 相似文献
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Haolun Wang Ning Wang Tao Liu Chunsong Zhao Xi Luo Lifang Zhang Yulei Chang Hui Wu 《Ionics》2016,22(5):731-734
The safety of lithium-ion battery is closely related to the anti-shrink and heatproof stability of the separator. In this paper, electrospun nylon66 (PA66) nanofiber-based membrane is used as lithium-ion battery separator, showing good thermodynamics properties via thermogravimetric analysis (TG), thermal shrinkage experiment, and tension test. Furthermore, electrospun nylon66 separator based battery exhibits better safety than the battery applying Celgard commerce separator under the condition of high temperature and severe vibration. Meanwhile, the electrochemical properties of both batteries are nearly identical. These facts prove that the electrospun nylon66 separator is an ideal separator candidate for power lithium-ion battery of electric vehicles. In addition, the nylon66 separator annealed in the air has higher tensile strength and better property of elongation than the unannealed one. 相似文献
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Insertion of Isolated Alkynes into Carbon–Carbon σ‐Bonds of Unstrained Cyclic β‐Ketoesters via Transition‐Metal‐Free Tandem Reactions: Synthesis of Medium‐Sized Ring Compounds 下载免费PDF全文
Yuanyuan Zhou Xianghua Tao Qiyi Yao Yulei Zhao Prof. Dr. Yanzhong Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(50):17936-17939
The transition‐metal‐free insertion of isolated alkynes into carbon–carbon σ‐bonds of unstrained cyclic β‐dicarbonyl compounds has been reported. These tandem reactions offer an efficient synthesis of medium‐sized ring or fused‐ring compounds through ring expansion. The methodology has the potential to be widely used throughout organic synthesis due to the easily accessible starting materials and mild reaction conditions. 相似文献