基于最优乘子潮流估计的故障筛选与排序

提出了一种用于电压稳定安全评估的快速故障筛选和排序方法。该方法从故障前的临界点出发,通过最优乘子潮流法计算得到的故障后边界点来估计故障后临界点,当初始点接近临界点,通过一次迭代即可满足所需的计算精度,从而快速地识别出非严重故障。对于严重故障和某些特殊情况的故障进行了分析并提出了解决办法,保证了对严重故障的估计精度。通过某一实际703节点系统算例验证了该方法的有效性。     

影响电网安全运行的各类故障及其相应对策

在统计分析了近10年来全国电网运行各类故障的基础上,对当前电网事故发生的特点和规律进行了分析总结,指出了制约电网安全运行的主要因素,并提出了相应的对策。     

云南电网一体化检修申请管理信息系统的建设

介绍云南电网一体化检修申请管理信息系统的架构设计,系统结构、系统功能、流程处理方式,应用效果。     

无痛肠镜下结直肠息肉摘除术的护理体会

随着麻醉技术的不断发展和无痛肠镜技术的成熟,无痛肠镜下治疗结直肠息肉已被越来越多的患者所认可.我院从2008年12月-2010 年10月期间在电子肠镜直视下用高频电刀切除结直肠息肉290例,现将护理体会报告如下.     

A statistical micromechanical model of multiple cracking for ultra high toughness cementitious composites

A new statistical micromechanical model of multiple cracking is proposed in which a general expression of the fiber bridging stress laws in the crack plane is established. In this model, the random distribution properties of fibers are considered. And the Weibull function is adopted to represent the flaw size distribution. The relationships of stress versus strain and crack width versus strain are proposed. The formulas of the crack width, crack space, strain capacity and fracture energy density at the end of multiple cracking processes are also deduced. The validity of the proposed model was demonstrated by experimental results.     

高炉环缝洗涤设备的制造与安装

对于高耗能和高排放的高炉炼铁工艺而言,一套先进可靠、成熟稳定的高炉环缝洗涤成套设备,具有重大意义.基于高炉环缝洗涤成套设备的重要性,从实际工程应用出发(昆钢6号高炉),阐述了环缝洗涤设备在制造和安装时的技术要点.     

南美蟛蜞菊洗手液的研制

以南美蟛蜞菊为原料提取制备叶绿素铜钠盐,添加相关试剂后制成具有清洁、杀菌的洗手液。通过正交试验,确定了洗手液的最佳配方:19 g复合表面活性剂、4.05 g羧甲基维生素钠、9 mL甘油、3 mL叶绿素铜钠盐、220 mL蒸馏水、3.51 g柠檬酸、适量香精。     

Materials applications of photoelectron emission microscopy

Photoelectron emission microscopy (PEEM) is a versatile technique that can image a variety of materials including metals, semiconductors and even insulators. Under favorable conditions the most advanced aberration corrected instruments have a spatial resolution approaching 2 nm. Although PEEM cannot compete with transmission or scanning electron microscopies for ultimate resolution, the technique is much gentler and has the unique advantage of imaging structure as well as electronic and magnetic states on the nanoscale. Since the image contrast is derived from spatial variations in electron photoemission intensity, PEEM is ideal for interrogating both static and dynamic electronic properties of complex nanostructured materials. Here, we review the key principles and contrast mechanisms of PEEM and briefly summarize materials applications of PEEM.     

关于照明设计与照明节能若干问题的探讨

本文拟就照明设计与照明节能方面的一些典型问题提出来进行分析、探讨。