一种电能质量分析仪谐波无缝采样分析检定方法

提出检定电能质量分析仪中无缝采样谐波分析的一种工程实用方法。通过对无缝采样测量与各种间隔采样测量的快速傅里叶变换（FFT）频率分量的差异性分析,提出聚集算法的检定模式;考虑实验室现有设备条件及被检仪器各种因素影响,选用特定的调制谐波作为检定波形,根据调制波高电平持续时间确定被检定电能质量分析仪3s内采样中断次数,提出差异比对的检定方法。另外,为了操作方便,还设计了基于虚拟仪器LabVIEW的检定系统。由计算机来控制检定信号的设置与发射,提高实际检定的效率。通过实验验证了该检定方法的有效性,并证实了该系统检定的准确性。     

Boost变换器的非线性最优控制系统

在Boost变换器状态空间平均模型的基础上,利用基于微分几何的非线性最优控制策略,建立了非线性仿射模型,且推导出了非线性状态反馈表达式,得到了Boost变换器状态反馈精确线性化模型,并对其控制器进行了设计,实现了系统在工作点大范围内变化时的稳定运行,有效提高了系统的动、静态性能.Matlab/Simulink仿真结果表...     

智能火焰检测系统在发电厂的应用

介绍ABB UVISOR智能火焰检测系统在华能济南黄台电厂9号机组的应用,分析安全火焰检测器SF810和智能火焰分析单元FAU810的工作原理、功能、特点及应用。     

下一代光接入技术助力宽带中国战略

在宽带中国战略即将推出的背景下,对目前主流的下一代光接入技术的需求、关键技术和产业状况进行了分析,探讨了下一代光接入技术可能的技术选择和演进趋势。     

超临界水氧化处理煤气化废水的试验研究及组合工艺思路探讨

采用间歇式反应器对碎煤加压气化废水的超临界水氧化处理效果开展了探索性试验研究,以污水处理达标为目标,对过程中的工艺条件及有害物质的去除效果进行了深入研究和评价。试验结果表明,温度和氧化系数对COD、NH3-N、挥发酚去除率效果显著,压力和反应时间影响不明显。优化条件下,利用SCWO技术处理煤气化废水,无需经过预处理及后续深度处理即可使出水主要指标达到国家一级排放标准。在此基础上,针对超临界水处理特点结合煤气化工艺路线创新性地提出组合工艺方案,以实现系统物料及能量的充分利用。     

Thermosensitive supramolecular hydrogels from atom transfer radical polymerization of polypseudorotaxanes self-assembled by triblock copolymer and α-cyclodextrins

We report novel thermosensitive supramolecular hydrogels with tunable crosslinking networks by using polypseudo-rotaxanes (PPRs) as macroinitiators in atom transfer radical polymerization and polyethylene glycol diacrylate (PEGDA) as bridge units. The PPRs were prepared by supramolecular self-assembly of α-cyclodextrin or 2-bromoisobutyryl bromide modified α-cyclodextrin (α-CD-BIBB) and triblock copolymer of F127 with bromopropionyl bromide terminals. The supramolecular hydrogels possess the crystal structure of inclusion complexes (ICs) and thermo-sensitive properties. The addition of mono-functional 2-hydroxyethyl methacrylate (HEMA) can enhance gelation. The swelling ratio (SR) was mainly influenced by the concentration of α-CD or modified α-CD, HEMA and PEGDA. The introduction of α-CDs was found to decrease the SR of hydrogels, while the introduction of α-CD-BIBBs could improve the SR. Meanwhile, gelation was tuned by regulating the concentration of HEMA. The SR of hydrogels was increased with the increase of the concentration of PEGDA, but decreased with the increase of that of HEMA. In the temperature range from 20 to 50 °C, the temperature sensitivity of hydrogels was mainly controlled by the state of gels. The introduction of PHEMA chains decreased the temperature responsivity of networks. The hydrogels prepared with α-CD-BIBBs threading onto the F127 chains showed the high thermo-sensitivity. The thermosensitive mechanism of hydrogels is due to the aggregation of PPO blocks in the networks.     

Learning cooperative grasping with the graph representation of a state-action space

In this paper we present a method for two robot manipulators to learn cooperative tasks. If a single robot is unable to grasp an object in a certain orientation, it can only continue with the help of other robots. The grasping can be realized by a sequence of cooperative operations that re-orient the object. Several sequences are needed to handle the different situations in which an object is not graspable for the robot. It is shown that a distributed learning method based on a Markov decision process is able to learn the sequences for the involved robots, a master robot that needs to grasp and a helping robot that supports him with the re-orientation. A novel state-action graph is used to store the reinforcement values of the learning process. Further an example of aggregate assembly shows the generality of this approach.     

基于dsPIC智能端子的研究

在电力系统中,电站监控设备与励磁设备之间的信息需求越来越多,而由于励磁设备自身的硬件限制,不可能无限制扩充其信号接口。文中提出的智能端子很好地解决了励磁设备信号接口不足的问题。介绍了一种基于dsPIC30F6014芯片的智能端子,通过试验结果证明,该智能端子不仅集成度高、硬件简单,而且成本低、方便可靠,具有一定的实际意义。     

The Impact of Cooperative Nodes on the Performance of Vehicular Delay-Tolerant Networks

Vehicular communications refer to a wide range of networks proposed for environments characterized by sparse connectivity, frequent network partitioning, intermittent connectivity, long propagation delays, asymmetric data rates, and high error rates. These environments may also be characterized by a potential non-available end-to-end path. To overcome these issues and improve the overall network performance, cooperation between network nodes must be severely considered. Nodes may cooperate by sharing their storage capacity, bandwidth, or even energy resources. However, nodes may be unwilling to cooperate due to a selfish behavior or to an intent to protect the integrity of their own resources. This selfish behavior significantly affects the functionality and performance of the network. This paper overviews the most recent advances related with cooperation on vehicular networks. It also studies the impact of different cooperation levels in the performance of Vehicular Delay-Tolerant Networks (VDTNs). It was shown that scenarios with a higher number of cooperative nodes present the best results in terms of bundle delivery delay.