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991.
992.
Wei Wu Wenjuan Zhou Tianping Chen 《IEEE transactions on circuits and systems. I, Regular papers》2009,56(4):829-839
In this paper, we focus on the problem of driving a general network to a selected cluster synchronization pattern by means of a pinning control strategy. Sufficient conditions are presented to guarantee the realization of the cluster synchronization pattern for all initial values. We also show the detailed steps on how to construct the coupling matrix and to modify the control strengths. Moreover, the method of adapting the coupling strength is provided to refine the result. 相似文献
993.
Dongpo Chen Lei Zhao Hongwei Diao Wenbin Zhang Ge Wang Wenjing Wang 《Journal of Materials Science: Materials in Electronics》2014,25(12):5322-5330
Four different low-temperature silver pastes were utilized to make metal grids by screen printing for silicon heterojunction solar cells. The rheological behaviors of the low-temperature silver pastes were characterized by viscosity test, thixotropy test, oscillatory stress sweep test and creep-recovery test. The correlationship between the screen-printing performance and the rheological properties was investigated. It was found that the shear thinning behavior and the thixotropy behavior of the silver pastes were desirable for the screen-printing process. An obvious viscoelastic behavior of the silver paste was also helpful for improving its printability. Further, good recovery and low creep and recovery compliances could minimize the printing defects and the tendencies to bleed out during the screen-printing, and thus increase the aspect ratio of the printed grids. 相似文献
994.
995.
介绍了-个采用PowerBuilder开发的提案管理系统.该系统采用客户端/服务器结构,分为用户管理、提案数据管理、任务数据管理、日志管理四个部分.描述了总体的设计思想、基本功能设计、数据库设计和关键技术.该系统能够帮助用户快速、方便的管理提案数据,在实际中得到了很好的应用. 相似文献
996.
Tong Ge Chang J.S. 《IEEE transactions on circuits and systems. I, Regular papers》2009,56(10):2353-2361
The total harmonic distortion (THD) and the power supply noise, qualified by the power supply rejection ratio (PSRR) and by the power supply induced intermodulation distortion (PS-IMD), are recognized to be potential drawbacks of class D amplifiers. In this paper, analytical expressions for the THD, PSRR, and PS-IMD of the bang-bang control class D amplifier (bang-bang amp) are derived; the bang-bang amp is arguably the most power-efficient class D amp for low-voltage power-critical applications including hearing aids. Based on the derived expressions, the effects of important parameters on the THD, PSRR, and PS-IMD are investigated, providing good insight to the design of the bang-bang amp to meet given design specifications. The analytical analyses are verified by comparing them against HSPICE simulations and hardware measurements. The bang-bang amp is also compared against the prevalent pulsewidth modulation class D amp, and in most cases, the former is shown to possess superior parameters, including lower power dissipation and hardware advantages for low-voltage power-critical applications. 相似文献
997.
Ge Zhan Lei-Qing Pan Shu-Bo Mao Wei Zhang Ying-Ying Wei Kang Tu 《European Food Research and Technology》2014,238(5):789-796
Recently, considerable attention has been paid to the biologically active of fruit and vegetable processing wastes. In this study, antibacterial properties and major bioactive constituents of Chinese water chestnut peels (CWCP) extracts and fractions were evaluated. The data displayed that ethyl acetate fractions (EF) from CWCP showed greater antibacterial activity than n-butanol fractions, methanol extracts and water fractions against three common foodborne pathogenic bacteria (Staphylococcus aureus, Escherichia coli and Listeria monocytogenes) assessed by the inhibition zone, minimal inhibition concentration and minimal bactericidal concentration values. In accordance with disc diffusion assay, S. aureus was more susceptible to EF than the other two pathogens. Furthermore, action-mode studies indicated that EF exhibited significant bactericidal activity against S. aureus by degrading and disrupting the cell wall and cytoplasmic membrane, ultimately the leakage of cell contents led to cell death. Finally, high-performance liquid chromatography coupled with photodiode array and electrospray ionization mass spectrometry was used for characterization of bioactive constituents in EF, and ten flavonoids aglycons were identified or tentatively identified. The results suggest that the extracts and fractions from CWCP could be potentially used as a possible food supplement to improve food safety by the control or elimination of foodborne pathogenic bacteria. 相似文献
998.
Surface texturing has been recognized to be very efficient in modifying the tribological performances of sliding surfaces. In the present article, a three-dimensional hydrodynamic lubrication model of the incompressible Newtonian fluid is proposed on the textured surface with a single spherical cap microdimple based on the full Navier-Stokes equation. The three-dimensional pressure field and velocity field of lubrication film are obtained by employing the finite volume method (FVM). The effects of geometric parameters and Reynolds number on pressure field, load-carrying capacity, friction force, and friction coefficient are investigated. Numerical simulation led the authors to conclude that the load-carrying capacity of the lubrication film is monotonously enhanced with increasing microdimple width and Reynolds number, and a reverse tendency is obtained for friction force and friction coefficient. The dimensionless optimum microdimple depth increases with the increase of the width and decreases with the increase of the Reynolds in the range of 0.80–2.00, which is responsible for the largest load-carrying capacity and the smallest friction coefficient. It has also been found that the optimum depth becomes a critical value to produce a vortex in the bottom of the dimple. Further analysis indicates that the optimum dimple depth becomes a transition of lubrication mode from hydrodynamic to mixed lubrication for a textured surface with a fixed microdimple. 相似文献
999.
L. Li Z. R. Yang M. Ge L. Pi J. T. Xu B. S. Wang Y. P. Sun Y. H. Zhang 《Journal of Superconductivity and Novel Magnetism》2009,22(7):667-670
In this paper, the pressure effect on superconductivity and magnetism has been investigated in FeSe
x
(x=0.80,0.88). The magnetization curves display anomaly at T
s1∼106 K and T
s2∼78 K except for the superconducting diamagnetic transition around T
c
∼8 K. The magnetic anomaly at T
s1 and T
s2 can be related to a ferromagnetic and an antiferromagnetic phase transition, respectively, as revealed by specific heat measurements.
The application of pressure not only raises T
c
, but also increases both T
s1 and T
s2.
相似文献
1000.
428XL仪器在可靠性、可操作性以及传输速度都得以提升的同时,其采集链由几段独立的电缆整合为一条整链,在野外检修采集链时,可能因为没有专用检测设备而无法按检修手册进行维修。本文讨论了WPSR和ST两种常用采集链在野外使用时,根据不同的地表条件有针对性采取的不同保护措施;并提出了适合于野外条件下进行采集链简易、快速维修的方法。 相似文献