Experimental studies on oxidizing removal of Cyclops of zooplankton

0 IntroductionCyclops couldn’t be effectively inactivated by theconventional disinfection such as chlorination due to itsstronger resistance to oxidation.In addition,the motilityof Cyclops makes it easily penetrate sand filter into theclean water tank in waterworks , even municipal servicepipe .Adult Cyclops , with body length of one to severalmillimeters, may be caught by naked eye to bring con-sumers unsanitary sense and may become disease trans-mission mediumas the host of pathogenic para…     

SAm级防撞活动护栏碰撞仿真分析

针对目前高速公路中央分隔带开口处活动护栏防撞等级较低的问题,提出了一种SAm级混凝土活动护栏及一种新型连接装置.基于有限元的方法,建立车辆与护栏的碰撞模型,通过LS-DYNA对车辆与护栏碰撞过程进行求解,根据不同车型的碰撞结果分别在缓冲,阻挡和导向性能上对护栏的安全性能进行评价,其中小型车辆与护栏碰撞后的OIV(Occ...     

三种咪唑物质检测技术研究进展

咪唑、2-甲基咪唑及4-甲基咪唑是一类五元杂环小分子化合物,2-甲基咪唑和4-甲基咪唑是同分异构体,常是氨(铵)法生产食品添加剂—焦糖色素的副反应产物,是影响食品添加剂安全性的重要因素.其中4-甲基咪唑会抑制细胞色素P450同功酶,引起人体畸变、癌变等症状,危害人体健康.近年来,有文献先后报道了咪唑及(2-或4-)甲基...     

Molecular mechanisms of BK channel activation

Large conductance, Ca²⁺-activated potassium (BK) channels are widely expressed throughout the animal kingdom and play important roles in many physiological processes, such as muscle contraction, neural transmission and hearing. These physiological roles derive from the ability of BK channels to be synergistically activated by membrane voltage, intracellular Ca²⁺ and other ligands. Similar to voltage-gated K⁺ channels, BK channels possess a pore-gate domain (S5–S6 transmembrane segments) and a voltage-sensor domain (S1–S4). In addition, BK channels contain a large cytoplasmic C-terminal domain that serves as the primary ligand sensor. The voltage sensor and the ligand sensor allosterically control K⁺ flux through the pore-gate domain in response to various stimuli, thereby linking cellular metabolism and membrane excitability. This review summarizes the current understanding of these structural domains and their mutual interactions in voltage-, Ca²⁺ - and Mg²⁺ -dependent activation of the channel. Received 25 September 2008; received after revision 23 October 2008; accepted 24 October 2008     

基于RSA体制的数字移动通信系统用户认证方案

设计了一种基于RSA体制的数字移动通信系统的用户身份认证方案.其安全性基于大整数的分解难题,能抵抗包括网内攻击的多种攻击.用户请求采用预计算的方式,有效减少了实时计算量,满足移动通信系统中用户请求的实时性要求.与基于离散对数的方案相比,本方案用户端和网络中心的计算量与存储量少,能高效实现连续请求.理论分析表明:本方案安全性高,计算复杂性和通信量低,网络中心存储量低,符合数字移动通信系统要求.     

MYH9 is associated with nondiabetic end-stage renal disease in African Americans

As end-stage renal disease (ESRD) has a four times higher incidence in African Americans compared to European Americans, we hypothesized that susceptibility alleles for ESRD have a higher frequency in the West African than the European gene pool. We carried out a genome-wide admixture scan in 1,372 ESRD cases and 806 controls and found a highly significant association between excess African ancestry and nondiabetic ESRD (lod score = 5.70) but not diabetic ESRD (lod = 0.47) on chromosome 22q12. Each copy of the European ancestral allele conferred a relative risk of 0.50 (95% CI = 0.39-0.63) compared to African ancestry. Multiple common SNPs (allele frequencies ranging from 0.2 to 0.6) in the gene encoding nonmuscle myosin heavy chain type II isoform A (MYH9) were associated with two to four times greater risk of nondiabetic ESRD and accounted for a large proportion of the excess risk of ESRD observed in African compared to European Americans.     

滞后广义系统的渐近稳定与镇定

广义系统的渐近稳定与镇定问题是广义系统理论的基本问题之一,在许多领域均有应用,时滞广义系统的研究与无时滞广义系统相比要困难得多。利用广义Lyapunov泛函方法研究了具滞后的广义系统的渐近稳定性和镇定问题,给出了渐近稳定判定定理,设计了适当的反馈律,以实现滞后广义系统的镇定,方法简单,直观,易于理解,给出的例子说明了该定理的可行性。     

一种VOP生成技术的研究与实现

视频对象平面(Video Object Plane,VOP)的生成是基于对象的编码技术以及基于图像内容的操作的基础。提出了以对象运动特征,在2D+T三维空间进行图像分割的VOP生成技术,特别是在摄像机运动的动态场景中,以全局运动估计技术补偿摄像机的运动,同时以边缘图像与差分图像进行匹配,克服对象高速运动时背景的遮拦与显露造成的影响,准确地生成VOP图像。针对真实场景的实际处理结果表明该算法是成功的。     

2型模糊集对率模系统可靠性分析的推广

鉴于2型模糊集对于模糊现象的描述更为深刻的特点,将系统的模糊成功和模糊故障用2型模糊集表示,引入模糊随机变量等数学工具对率模系统可靠性进行了分析,得到了率模可靠度,率模寿命,率模故障率等结论,推广了文献［1］的结果     

高动态GPS/INS组合导航算法研究

首先介绍了新型深组合GPS/INS系统原理图及组合导航滤波算法。在该算法中,组合卡尔曼滤波器除完成INS误差及GPS接收机时钟误差的估计外,还参与了GPS码跟踪,即完成传统码跟踪环中环路滤波器的功能。采用自适应码跟踪误差估计器补偿组合卡尔曼滤波器测量值中的相关分量,从而消除了传统组合中不稳定的主要根源。然后进行了计算机仿真计算,仿真结果表明,新型深组合GPS/INS导航算法适用于机动性较高的载体。