Current progress of study on gas electron multiplier

Recent progress of study on gas electron multiplier （GEM） has been described. Due to its fast time response and excellent position sensitivity, the GEM will find wide applications in particle physics, medicine and astrophysics. These potential applications have been briefly introduced.     

"小触大"控制系统在机组改造中的应用实践

本文主要介绍了“小触大”控制系统在机组改造中的方案及其成功应用,说明了老式机组改造巨大的节能前景。     

晶闸管调功器的一种数字化触发电路

针对电阻炉超温、过流、缺相等故障的保护、报警及显示功能,提出一种新型的晶闸管数字化触发电路,介绍了该触发电路硬件系统的构成及工作原理,并对软件编程进行了论述。     

基于TSC控制技术的快速响应自动消弧装置

自动消弧装置是由一种基于晶闸管投切电容(TSC)控制技术的自动调谐消弧线圈、接地变压器和互感器等组成的成套设备。它可对线路的单相接地故障做出快速响应,并精确补偿接地电流。此装置很好地解决了3个技术难点：第一,线路对地容抗的精确测量,误差在2%以下;第二,根据线路电容电流和人工中性点电压的变化来智能判别单相接地故障;第三,采取串联小电抗,过零投切和加装风机等措施,以确保晶闸管的安全运行。可编程逻辑控制器（PLC）、触摸屏式人机界面（HMI）和过零触发板构成了该装置的控制系统。模拟试验和实际应用表明该装置能够取得理想的效果。     

基于晶闸管反并联的有载分接开关的设计

设计了基于晶闸管反并联的有载分接开关的主接线形式,完成了有载分接开关自动调压工作流程的设计,同时还设计了晶闸管的触发电路和过电压RC缓冲电路。经理论分析本设计可以满足10kV电力用户有载调压的需求,具有广阔的发展前景。     

小折射爆炸机测试仪的研制

本文在对HVB型爆炸机的工作原理进行分析的基础上，针对野外小折射用HVB系列爆炸机在二线维修后的测试问题，介绍了所研制出的一种能方便、快捷地检验修理后的爆炸机是否合格的测试仪，即小折射爆炸机测试仪。     

Suppression of MR gradient artefacts on electrophysiological signals based on an adaptive real-time filter with LMS coefficient updates

Electrocardiogram (ECG) acquisition is still a challenge as gradient artefacts superimposed on the electrophysiological signal can only be partially removed. The signal shape of theses artefacts can be similar to the QRS-complex, causing possible misinterpretation during patient monitoring and false triggering/gating of the MRI. For their real-time suppression, an adaptive filter is proposed. The adaptive filter is based on the noise-canceller configuration with LMS coefficient updates. The references of the noise canceller are the three gradient signals that are acquired simultaneously with the noisy ECG. Tests were done on patients, on volunteers and using an MR-safe ECG simulator. The noise cancellers performance was measured offline, simulating real-time processing by point-by-point operations. To create worst-case scenarios, clinical sequences with strong- and fast-switching gradients have been chosen. The noise-cancelling filter reduces the gradient artefacts peak amplitudes by 80–99% after adaptation, without changing the desired ECG signal shape. The estimated reduction of total average power of the MR gradient artefacts is 62–98%. The proposed filter is capable of reducing artefacts due to strong- and fast-switching gradients in real-time applications and worst-case situations. The quality of the ECG is sufficiently high that a standard one-lead QRS-detector can be used for gating/triggering the MRI. For permanent patient monitoring, further improvements are needed.     

Rule activation techniques in active database systems

Efficient activation of rules is a fundamental issue in active database systems; choosing the suitable rule activation technique is therefore an important task. We have developed a technique, called join pattern indexing, to support incremental update of rule-derived data. In this paper, we compare join pattern indexing with discrimination networks (Rete and TREAT) for data-derivation rules. A performance study based on a stochastic model indicates that join pattern indexing is more efficient than discrimination networks in many cases.     

IMS业务体系架构中业务触发机制分析

分析了IP多媒体子系统(IMS)业务体系结构中的业务触发机制,包括业务触发数据、S-CSCF上的处理流程等,结果说明,该触发机制保证用户发起IMS呼叫时能够正常使用IMS业务体系结构中所提供的业务.     

压力信号器振动环境下误触发现象机理

基于AMESim系统动力学仿真软件,建立压力信号器及其试验系统仿真模型,提出以阀门内部运动件与阀门壳体相对运动为考察目标,通过理论分析给出可行的振动环境与仿真模型的接口形式,以此建立振动环境下压力信号器特性分析模型,经验证,模型仿真结果与试验结果吻合良好.采用此振动环境下模型对误触发现象进行机理研究,并给出误触发现象抑...