FH4-060型高分辨堆积拒绝门

本文介绍一种用于快闪烁探测器能谱测量系统的堆积拒绝门,其分辨时间好于10ns。线路采用更新计时器,定时电容的更新时间包含在门宽度之内,原则上电路无死时间,输入计数率无上限,特别适用于高计数率的场合。电路内附反符合控制输入和门信号放大器,可实现对多道分析器的堆积拒绝和反符合控制。     

一类多输入非线性系统的同时H∞镇定

研究了一类多输入非线性系统同时H∞镇定问题. 提出了可系统地构造公共二次控制储能函数(Control storage function, CSF)的方法. 基于公共二次控制储能函数,设计了可同时H∞镇定闭环系统的连续控制律. 通过一个例子说明了本文所提出方法的有效性.     

一类高阶非线性系统的级联自抗扰控制

针对类似板球系统的一类高阶、强耦合、不确定非线性系统,利用backstepping算法的思想,提出以多个低阶自抗扰控制器级联实现控制的方法.通过各低阶自抗扰控制器的扩张状态观测器观测出各级对象的内外扰动,然后进行补偿,较好地解决了高阶非线性系统的不确定性、耦合性及干扰抑制问题.以板球系统的轨迹跟踪控制为例进行研究,所得结果表明,该方案适用于复杂高阶非线性级联系统的控制,具有良好的动态特性及鲁棒性.     

基于边缘分析和颜色统计的车牌精确定位新方法*

针对车牌的边界定位不准确和伪车牌较多的问题,提出了一种边缘分析和颜色统计相结合的车牌精确定位的新框架。该框架主要分为预处理、粗定位、精确定位和伪车牌排除四个模块。对图像作边缘检测和二值化等预处理,用投影法粗定位出候选区域,利用候选区域及其周围的边缘和颜色的信息实现车牌的精确定位。对于定位结果有多个候选区域的情况,对候选区域进行排序,再将排序结果按顺序传入字符分割模块,从而有效排除非车牌区域的影响。实验结果表明,该方法精确度和准确率高、实时性强,适用于不同的应用场合。     

The use of energy windowing to discriminate SNM from NORM in radiation portal monitors

Energy windowing is an algorithmic alarm method that can be applied to plastic scintillator-based radiation portal monitor (RPM) systems to improve operational sensitivity to certain threat sources while reducing the alarm rates from naturally occurring radioactive material. Various implementations of energy windowing have been tested and documented by industry and at Pacific Northwest National Laboratory, and are available in commercial RPMs built by several manufacturers. Moreover, energy windowing is being used in many deployed RPMs to reduce nuisance alarms and improve operational sensitivity during the screening of cargo. This paper describes energy windowing algorithms and demonstrates how these algorithms succeed when applied to “controlled” experimental measurements and “real world” vehicle traffic data.     

Effect of FTY720 and ICAM-1 mAb mono and combination therapy in cardiac allo-transplantation in rats

Objective To observe the effect of FTY720 and ICAM-1 mAb mono and combination therapy in cardiac silo-transplantation in rats. Methods Rats were randomly assigned to 9 groups, heart allo-transplantation were performed in abdominal site with micro-surgical technique. Recipients with allografts were treated with different doses of FTY720 and(or) ICAM-1 mAb. Graft survival, histopathology andlevel of serum IL-2, IFN-γ, IL-4, IL-10were investigated. Results Low doses of FTY720 (lmg/kg) combined with ICAM-1 mAb achieved synergistic effect in the prolongation of cardiac graft survival, combination index(CD =0.67. Conclusion Concomitant therapy of FTY720 and ICAM-1 mAb achieved a synergistic effect in the prolongation of heart allograft survival in rats.     

湖南电网500/220 kV电磁环网解环探讨

“十一五”期间湖南电网发展迅速，500／220kV电磁环网运行问题日益突出。如何合理确定湖南电网的解环方式以保证湖南电网安全稳定运行十分必要。研究表明，2010年前在娄底与湘潭之间220kV网络开环是合适的。     

两种甩负荷试验方法的比较

分别介绍了邹县电厂 1号机组、华德电厂 4号机组经过改造后进行常规法和测功法甩负荷试验的有关情况 ,并对甩负荷试验中临时技术措施、机组运行方式、旁路的投入 ,以及个别保护的解除等一些技术问题进行了分析与探讨。认为 OPC( 1 0 3 %超速保护 )动作准确是甩负荷成功的关键 ,必须在甩负荷前对 OPC逻辑控制进行认真、仔细的检查 ,同时要尽量减少测量试验信号的迟缓 ,不要影响机组的安全运行     

Deadbeat control with disturbance rejection

A deadbeat control problem with disturbance rejection is considered for a SISO discrete time plant. Disturbances are supposed to enter into the input to the plant and the output from the plant. The two-degree-of-freedom controllers are employed to internally stabilize the feedback control system, to make the output of the plant track a reference signal and to reject the disturbances in the sense of the deadbeat response. Necessary and sufficient conditions for the problem to have a solution are shown. And the set of all controllers meeting the design requirements are represented using two free polynomials.     

470 t/h大型循环流化床锅炉甩负荷试验研究

包头第一热电厂扩建工程470t/h循环流化床锅炉配125 MW双抽式汽轮发电机进行甩负荷试验研究,结合循环流化床锅炉的自身特点及没有高低旁路的情况下进行甩负荷,探讨如何控制汽温汽压等参数；根据循环流化床锅炉的特点,切断燃料后锅炉仍能维持一定时间的正常燃烧,并保持一定时间内电负荷和床温稳定,待床温及电负荷有下降趋势时,将电负荷甩至零,不致造成甩负荷后锅炉超温超压,即安全门未动作,管壁温度不超限,使锅炉在甩负荷后可迅速接带负荷；通过对甩负荷过程中锅炉燃料系统、烟风系统、汽水系统等参数的理论分析及实际甩负荷试验过程观察,证明循环流化床锅炉具有快速变负荷的特性。