美国联邦检察官的地方反腐行动之正当性辨析

美国司法部在未获得国会立法明确授权的情况下,自上世纪70年代初始启动了由联邦检察官直接参与调查和检控各州腐败官员的大规模廉政行动.该行动历时四十余年,取得了显著成效,但一直被美国各界持异议者视为对各州及地方政府的政治独立和现代法治构成了最为严重、最具破坏性的侵蚀.立足于美国语境,从联邦检察官与各州民选检察官之间的比较优势、联邦法官群体反腐伦理倾向、社会舆论基础以及美国实用主义政治、法律传统等多维角度,探究联邦检察官的地方反腐行动得以正当化的因素,有助于加深对美国民主与法治的认识,吸取有益于中国反腐实践的经验.     

Detection of cracks in simply-supported beams by continuous wavelet transform of reconstructed modal data

This paper proposes a new approach for damage detection in beam-like structures with small cracks, whose crack ratio [r = H_c/H] is less than 5%, without baseline modal parameters. The approach is based on the difference of the continuous wavelet transforms (CWTs) of two sets of mode shape data which correspond to the left half and the right half of the modal data of a cracked simply-supported beam. The mode shape data of a cracked beam are apparently smooth curves, but actually exhibit local peaks or discontinuities in the region of damage because they include additional response due to the cracks. The modal responses of the damaged simply-supported beams used are computed using the finite element method. The results demonstrate the efficiency of the proposed method for crack detection, and they provide a better crack indicator than the result of the CWT of the original mode shape data. The effects of crack location and sampling interval are examined. The simulated and experimental results show that the proposed method has great potential in crack detection of beam-like structures as it does not require the modal parameter of an uncracked beam as a baseline for crack detection. It can be recommended for real applications.     

珠海发电厂电动给水泵电动机保护动作分析

珠海发电厂1号机1号电动给水泵启动中综合保护继电器保护动作,跳开电动给水泵电源开关,马达端盖出风口有青黑色烟气冒出.根据综合保护继电器记录数据,利用矢量分析法,结合继电保护及电力系统稳态、暂态理论知识,在最短时间内分析出电动机发生了B相绕组匝间短路,为确定电动机故障点提供了理论支持,确保了故障电动机的及时维修,并在电动给水泵进行解体后,验证了理论分析的正确性.     

A DCT-based multipoint video composition scheme

针对视频会议应用中传统的像素域多路视频混合方法存在运算复杂度高、画面质量损伤的问题,提出了一种基于压缩域的替代方法,并给出了详细的码流映射算法步骤.该方法按照混合后多画面的空间位置关系,通过对输入的多路码流中宏块编码次序的重排和语法元素的映射,在码流级别将多路视频合成到同一画面中,并采取提前量化策略消除可能出现的二次量化失真,从而可兼具处理速度快和高保真的双重优点.以H.263为例验证了此方法的有效性.实验结果表明,与编解码器级联的方法相比,此方法的峰值信噪比(PSNR)平均提高2dB,运算效率提高百倍以上.此研究工作有望为正在制定的国际视频编码标准H.265贡献一种视频混合解决方案.     

Initial bond formation in thermosonic gold ball bonding on aluminium metallization pads

The morphological features of lift-off footprints on the aluminium metallization pads were investigated to gain an understanding of the effects of bonding parameters on formation of initial bonds during thermosonic gold ball bonding. The obtained results showed that metallurgical bonding initiated at the peripheral areas of the contact area situated along the direction of ultrasonic vibration. Those areas extended inwards with an increase in ultrasonic power. Both the external bonded area and central non-bonded area increased with increasing bonding force. Based on the evolution of footprints, the bonding models were proposed, and the effects of the bonding parameters on the formation of initial bonds were discussed.     

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。     

塑料材料的摩擦学性能研究综述

述了塑料材料摩擦、磨损的研究概况,详细阐述了摩擦因数、载荷、温度、速度、润滑、表面粗糙度pv值和热性能等因素对塑料材料摩擦性能的影响,介绍了磨损的衡量标准和测量方法.     

建筑加层设计楼梯消防改造初步探讨——以一个综合楼为例

本文通过某综合楼加层改造的设计实践,对消防改造中楼梯改造进行技术探讨及思考,力求为其他同类项目提供参考。     

钢筋工程优化在海上国际花园的应用

结合海上国际花园项目在施工过程中所遇到的钢筋问题,详细阐述了如何正使做用平法解决的,并保证了钢筋工程的施工质量。     

提高露采末期爆破效率

介绍了眼前山铁矿露天开采末期爆破现状,并提出了提高露采末期爆破效率的技术管理措施。