一系列基于CCⅡ的Q增强二阶滤波器     

梁荣新 《广东技术师范学院学报》1999,(4)

本文提出了一种用单块有源CCⅡ实现的新型有源网络,它可以实现二阶高通、低通和带通滤波器,其特点是电路的ω0和Q值可分别由两个接地元件独立调节,文中还给出了电路的设计、灵敏度分析和实验结果。  相似文献   

基于CCⅡ-的电压模式全通滤波器实现     

黄满池  彭良玉  董文蔚 《湖南师范大学教育科学学报》1998,(2)

本文提出了用单个第二代电流传送器（CCⅡ－）实现二阶全通、陷波和一阶全通转移函数的通用电路,此通用电路具有高输入阻抗和低无源灵敏度特性．  相似文献   

The NICE OECD countries' geographic search filters: Part 2—validation of the MEDLINE and Embase (Ovid) filters     

Lynda Ayiku  Thomas Hudson  Ceri Williams  Paul Levay  Catherine Jacob 《Journal of the Medical Library Association》2021,109(4):583

Objective:We previously developed draft MEDLINE and Embase (Ovid) geographic search filters for Organisation for Economic Co-operation and Development (OECD) countries to assess their feasibility for finding evidence about the countries. Here, we describe the validation of these search filters.Methods:We identified OECD country references from thirty National Institute for Health and Care Excellence (NICE) guidelines to generate gold standard sets for MEDLINE (n=2,065) and Embase (n=2,023). We validated the filters by calculating their recall against these sets. We then applied the filters to existing search strategies for three OECD-focused NICE guideline reviews (NG103 on flu vaccination, NG140 on abortion care, and NG146 on workplace health) to calculate the filters'' impact on the number needed to read (NNR) of the searches.Results:The filters both achieved 99.95% recall against the gold standard sets. Both filters achieved 100% recall for the three NICE guideline reviews. The MEDLINE filter reduced NNR from 256 to 232 for the NG103 review, from 38 to 27 for the NG140 review, and from 631 to 591 for the NG146 review. The Embase filter reduced NNR from 373 to 341 for the NG103 review, from 101 to 76 for the NG140 review, and from 989 to 925 for the NG146 review.Conclusion:The NICE OECD countries'' search filters are the first validated filters for the countries. They can save time for research topics about OECD countries by finding the majority of evidence about OECD countries while reducing search result volumes in comparison to no filter use.  相似文献   

转炉烟气一次除尘废水处理流程设计简介     

任玉斌 《中国科技纵横》2010,(11):413-413,128

文中对转炉烟气一次除尘废水处理工艺流程作了简单的介绍,该流程能够使钢厂转炉烟气除尘水基本实现闭路循环,达到节能减排的良好效果。流程中粗颗粒分离必不可少,而且在斜板沉淀池前加了电磁场辅以絮凝,使后序处理更加理想。  相似文献   

基于ANSYS/Maxwell的感应滤波配电变压器设计与实验研究北大核心     

张辉  李昌易  李德路  张晓 《实验技术与管理》2022,(1):72-78

该文提出了一种适用于低压配电网系统下的新型感应滤波配电变压器设计方法,并将其应用于综合性创新实验的教学案例中。在感应滤波配电变压器的设计中,将感应滤波技术应用于采用Ddy联结组别的配电变压器中。通过建立电路数学模型,推导阀侧产生的谐波电流与网侧电流之间的关系,揭示感应滤波配电变压器的滤波特性。该文采用ANSYS/Maxwell软件建立新型变压器的3D模型,在模型上通过仿真能量法对比工程磁路法,验证变压器绕组间短路阻抗满足技术要求;并通过磁路耦合添加滤波支路,监测变压器的网侧电流,验证其可以有效滤除电网谐波污染。最后通过实验验证了所设计的变压器的正确性和有效性,进一步激发了学生的学习兴趣和创新热情。  相似文献