无键联接传动的特点及锥面弹性衬套设计和应用

无键联接在特殊行业和工况中是键联接传递动力和运动的有力补充,介绍了工程上应用的圆弧三边形型面联接、弹性环无键联接、圆柱面过盈联接等几种无键联接传动方式及其工作原理,并分析了各自的性能特点和应用情况。针对无键联接传动的特点、特殊行业和工况的应用实际,设计了锥面弹性衬套无键联接传动结构并介绍了其在工程中的实际应用。     

配置抗冲切钢筋的混凝土异形柱-板柱连接试验研究

在9个柱截面为三种典型异形柱(十字形、T形和L形) -板柱连接未配置抗冲切钢筋时的冲切特性试验基础上,以十字形柱-板柱连接为代表,通过三个配置抗冲切钢筋试件与三个未配抗冲切钢筋试件的对比试验,研究了异形柱-板柱连接配置抗冲切钢筋后的冲切特性,同时将锚栓和箍筋的抗冲切性能进行了对比。试验结果表明,抗冲切钢筋可以有效地提高板的受冲切承载力和延性,在改善延性方面,锚栓比箍筋更有效。另外,将国外几个主要规范ACI3 18、BS8110及MC90 ,关于对非矩形荷载面冲切临界截面周长的规定进行了比较,从试验结果看,ACI3 18规范的取法更合理。     

郑411块超稠油试油试采工艺技术应用

郑411块沙三段地层疏松出砂、原油粘度高，属中深层超稠油，常规试油试采方法难以突破出油关，采用APR全通径氮气垫测试、地层与井筒复合防砂、水平井配合直井蒸汽吞吐、氮气泡沫封堵调剖和井筒加热举升稠油等配套工艺技术，取得了较好的效果，为中深层超稠油油藏的开发提供了技术思路。     

考虑塑性铰外移的钢框架梁柱连接设计

介绍美国联邦突发事件管理局 (FEMA)对 1 994年北岭地震中焊接钢框架节点破坏原因的正式解释 ,说明塑性铰外移的必要性。此外 ,还介绍了塑性铰外移的两种基本形式以及狗骨式 (RBS)连接的有关设计规定和适用条件 ,其设计方法可供我国工程设计人员参考。     

D.yn11配电变压器过电流保护的特点

分析D．yn11配电变压器低压倒发生不同类型故障时，流过高压侧各相电流的大小及相位，从而比较保护用电流互感器在不同接线方式时过电流保护的灵敏度及可靠性；并提出过电流保护应注意的问题。     

A simplified cascade current‐source inverter interconnected to a single‐phase three‐wire distribution system and its application to electric energy storage systems with batteries

A novel current source inverter system interconnected to the single‐phase grid is proposed. It has the same construction as the conventional three‐phase current source inverter that is interconnected to the single‐phase three‐wire distribution system. Though the proposed circuit has no output transformer, it can be equivalently performed as the single‐phase double cascade inverter by diverting the pole transformer in the utility system. By controlling the appropriate scheme, the output currents can be obtained as the five‐level waveforms and their distortions can be decreased sufficiently. It is applied to the interactive electric energy storage system with batteries and the basic discharging characteristics are discussed experimentally. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 150(2): 50–61, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10380     

绥高#2线线路保护2动作分析

对高岭站2009年6月15日绥高#2线线路保护动作的原因进行深入分析,介绍处理措施。     

Speech Enhancement via Residual Dense Generative Adversarial Network

Generative adversarial networks (GANs) are paid more attention to dealing with the end-to-end speech enhancement in recent years. Various GAN-based enhancement methods are presented to improve the quality of reconstructed speech. However, the performance of these GAN-based methods is worse than those of masking-based methods. To tackle this problem, we propose speech enhancement method with a residual dense generative adversarial network (RDGAN) contributing to map the log-power spectrum (LPS) of degraded speech to the clean one. In detail, a residual dense block (RDB) architecture is designed to better estimate the LPS of clean speech, which can extract rich local features of LPS through densely connected convolution layers. Meanwhile, sequential RDB connections are incorporated on various scales of LPS. It significantly increases the feature learning flexibility and robustness in the time-frequency domain. Simulations show that the proposed method achieves attractive speech enhancement performance in various acoustic environments. Specifically, in the untrained acoustic test with limited priors, e.g., unmatched signal-to-noise ratio (SNR) and unmatched noise category, RDGAN can still outperform the existing GAN-based methods and masking-based method in the measures of PESQ and other evaluation indexes. It indicates that our method is more generalized in untrained conditions.     

智能力敏传感器的研制

针对传统的差压密度计和压力式液位计分别存在可靠性不高、不适用于介质密度经常变化的场合的问题,设计了一种基于Freescale MC9S08AW60微控制器的智能力敏传感器,详细介绍了该传感器主要电路的设计。该智能传感器实现了数据采集、信号处理、数据通信和电流环输出式数模转换功能。实际应用表明,在-20～+80℃的工作温度范围内,密度测量精度可达±5kg/m3,液位测量不受悬浮液回流和液位波动的影响,很好地满足了工业现场的应用。     

可变频变压器的建模仿真与分析

采用高压直流输电方式连接两个异步电网存在谐波干扰、换相失败、难以实现功率平滑调节、无功功率不能随有功功率传输等问题。文章介绍了可变频变压器的的基本结构及原理,研究了可变频变压器的数学模型及控制模型,给出了可变频变压器传输功率与直流驱动电动机提供的驱动转矩之间的数学关系式,在此基础上采用PSCAD软件搭建了可变频变压器模型并进行了仿真研究。仿真结果表明,可变频变压器可以实现两个异步电网之间的连接并进行功率双向平滑传输,响应速度快;通过转速控制器控制直流驱动电动机的转速可使旋转变压器的转速恒定,以弥补两个电网的频差,维持系统平衡。