10kV配电室操作控制电源电压下降的解决措施

本提出了10kV配电室操作电压下降的现场解决方案。     

珠钢滤波-无功补偿优化调整方案

本文主要论述了珠钢滤波-无功补偿优化调整方案在生产中的应用。     

The stress intensity factors for a short crack partially penetrating an inclusion of arbitrary shape

Some approximate solutions for predicting the stress intensity factor of a short crack penetrating an inclusion of arbitrary shape have been developed under mode I and mode II loading conditions. The derivation of the fundamental formula is based on the transformation toughening theory. The transformation strains in the inclusion are induced by the crack-tip field and remotely applied stresses, and approximately evaluated by the Eshelby equivalent inclusion theory. As validated by detailed finite element (FE) analyses, the developed solutions have good accuracy for different inclusion shape and for a wide range of modulus ratio between inclusion and matrix material.     

Passivity‐based sliding mode control for nonlinear systems

Passivity with sliding mode control for a class of nonlinear systems with and without unknown parameters is considered in this paper. In fact, a method for deriving a nonlinear system with external disturbances to a passive system is considered. Then a passive sliding mode control is designed corresponding to a given storage function. The passivity property guarantees the system stability while sliding mode control techniques assures the robustness of the proposed controller. When the system includes unknown parameters, an appropriate updated law is obtained so that the new transformed system is passive. The passivation property of linear systems with sliding mode is also analysed. The linear and nonlinear theories are applied to a simple pendulum model and the gravity‐flow/pipeline system, respectively. Copyright © 2008 John Wiley & Sons, Ltd.     

Comment on Greenwood (2007): Solving the puzzle of structure/function relations in the aging brain?

Neuroimaging experiments have shown that prefrontal regions of the brain, which have the most age-related volume loss, are also the regions most likely to be more active in older adults than in younger adults. In an attempt to solve this puzzle, P. M. Greenwood (see record 2007-15625-001) has proposed a cascade that flows from age-related atrophy in the brain to changed processing strategies that result in plastic changes in regions adjacent and contralateral to the atrophic areas, culminating in greater functional activity. This hypothesis should stimulate research into these mechanisms and hopefully will ultimately inform researchers' ability to rehabilitate cognitive disorders in the elderly. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

大功率开关电源的设计与实现

介绍了开关电源设计中需要考虑的几个基本问题,包括频率的确定、最大占孔比Dm的确定、逆变变压器的设计和开关功率管的选择,并以一种1 kW的PWM大功率半桥式开关电源为例,详细介绍实际的开关电源设计方案,并给出了实验结果.     

InP基应变补偿结构偏振不灵敏半导体光放大器制作的研究

为了制备偏振不灵敏的半导体光放大器(SOA)，将有源区设计为由4个压应变、3个张应变阱层及晶格匹配的垒层InGaAsP交替组合而成的应变补偿结构。器件做成带有倾角的扇形脊形波导结构，避免了常规制作SOA的复杂工艺。对样品3在80～125mA电流范围内，获得了偏振灵敏度≤0．6dB．最小可达0．1dB；较大的电流范围内FWHM值为40nm。     

一种基于bit位的运动补偿方法

本文讨论了等离子体显示屏所特有的在显示运动画面时出现的伪轮廓线现象，对产生的原因进行了分析并给出了软件模拟的结果。在此基础上，提出了一种基于bit位的运动补偿方法来改善运动图像的画面质量，同时根据人眼的视觉特征对补偿方法做了进一步的优化。最后对基于bit位的运动补偿方法进行了比较和验证，结果表明基于bit位的运动补偿方法可以基本消除运动画面的伪轮廓线现象。