Stability and dissipative analysis for a class of stochastic system with time-delay

This paper deals with the stability and dissipative problem of a class of stochastic hybrid system. The system under study involves Markovian jump, impulsive effects and time delay, which are often encountered in practice and are the sources of instability. Our attention is focused on analysis of whether the stochastic hybrid system with time-delay is stochastically asymptotically stable and strictly (Q, S, R) dissipative. By introducing an extra artificial time instance, the equivalent system is obtained and the sufficient conditions are derived by using linear matrix inequality (LMI) techniques. The main results of this paper unify the existing results on H_∞ control.     

Effect of Mixed Solvents and Additives on the Habit Modification of 6-APA Crystals

6-aminopenicillanic acid (6-APA) crystals obtained under different physical and chemical conditions of the solutions may present different habits. The habits of diamond-shaped plates are desirable compared with other habits of 6-APA crystals. To obtain ideal 6-APA crystals, the effects of the mixed solvents and additives on 6-APA crystal habits were investigated. Ethanol or acetone was used as the organic solvent, and impurities existing in the ,6-APA purification process were used as the additives. 6-APA growth habits were changed when the concentrations of ethanol, acetone or phenyl acetic acid were increased to exceed their critical concentration. The observed results show that the dominant face on 6-APA crystals was identified to be , {020}, but the overall habit was controlled by the relative growth rates of the : 101 and {002} faces. Crystal growth rates and habits can be appreciably changed by specific adsorption of additives on crystal faces. In some cases solvent molecules can act in a similar way and may be regarded as bulk additives. The effects of additives and organic solvents on 6-APA crystal habits were the results of adsorption effect,which fitted the experimental results quite well.     

反应挤出制备HDPE/PA 6/MMT复合材料研究

通过反应挤出制备了高密度聚乙烯/聚酰胺6/蒙脱土(HDPE/PA 6/MMT)复合材料,研究了MMT在HDPE/PA 6共混物中的分散和分布情况,及其对共混物相态结构的影响。从XRD和TEM的结果中可以看出,有机化蒙脱土(OMMT)选择性地分布在PA 6相内以及两相的界面上,钠基蒙脱土(Na+MMT)则主要分布在PA 6相内;大部分OMMT得到较好的剥离或插层,而Na+MMT出现明显的团聚。FE-SEM分析结果表明,增大MMT的含量会导致PA 6的相态尺寸变大,粒径分布变宽。流变分析结果表明,由于OMMT部分分布于两相界面处,从而增强了界面结合,对共混物起到了增容作用。     

用VB实现文件查找的几种方法

现今电脑硬盘的容量越来越大,其中储存的文件也越来越多.开发能够实现文件快速查找功能的应用程序,必将具有广泛的应用前景.利用VB6.0提供的强大文件操作对象(File System Object),编制了几种切实可行的文件快速查找程序.     

多媒体计算机房综合控制系统设计与实现

基于VB和单片机设计实现了多媒体计算机房综合控制系统。该系统可控制学生机的批量开启、关闭和重启,可发送即时短消息并支持通过遥控器演示PPT课件。该系统使用简便,响应迅速,既能帮助管理员完成繁复的工作,提高机房的管理效率和水平,又能帮助教师充分利用多媒体教学资源开展教学活动,提升教学效果。     

L-fuzzy相对T-1,相对T0与相对次T0分离性

定义了L-fuzzy拓扑空间中的相对T-1，相对T0与相对次T0分离性，讨论了相对T-1，相对T0与相对次T0分离性的一系列性质．证明了相对T-1，相对T0与相对次T0分离性是遗传的、传递的、弱同胚不变的及可乘性等性质，并给出了一些例子。     

用VB程序设计一个计算器

技校学生在学习VB语言时,找不到简单而实用的例子,其实在计算机附件中有一个“计算器”,通过用VB语言设计一个计算器,加深对VB语言的认识。     

IPv6环境下IPSec协议安全机制的研究与实现

介绍了IPv6的发展概况,分析了IPsec协议的安全体系结构、各部分功能及其相互间关系、IPsec协议在IPv6中的工作原理等,探讨了IPsec协议在IPv6中应用所存在的问题,详细分析了其在Windows、Linux等操作系统中的软件实现过程。     

6-甲基-2-（α-羟甲基）-1H-苯并咪唑荧光增敏探针法测定蛋白质

以6-甲基-2-（α-羟甲基）-IH-苯并咪唑（MHMBM）作为荧光探针,利用蛋白质对MHMBM荧光增敏作用,建立了测定人血清总蛋白的新方法。结果表明,在中性水溶液中,MHMBM的荧光强度与牛蛋白（BSA）的浓度呈良好的线性关系,相关系数（r）为0．9995,检出限2．3μg／mL,线性范围4．6—60．0μg／mL。本方法用于测定两种样品溶液中的总蛋白,RSD（n=6）分别为1．7％和1．3％,回收率95．5％和98．6％。     

Teachers’ perceptions of assessments of their mathematical knowledge in a professional development course

The purpose of the project reported in this article was to evaluate how assessing teachers’ mathematical knowledge within a professional development course impacted from the teachers’ perspective their learning and their experience with the course. The professional development course consisted of a 2-week summer institute and the content focus was geometry. We had decided to assess the mathematical learning of the teachers during this professional development course for various accountability reasons, but were concerned about possible negative by-products of this decision on the teachers and their participation. Thus, we worked to design assessment in ways that we hoped would minimize negative impacts and maintain a supportive learning environment. In addition, we undertook this evaluation to examine the impacts of the assessment, which included homework, quizzes, various projects, and an examination for program evaluation. Seventeen grade 5–9 teachers enrolled in the course participated in the study by completing written reflections and by describing their experiences in interviews. We learned that while our original intent was “to do no harm,” the teachers reported that their learning was enhanced by the assessment. The article concludes by describing the various properties of the assessments that the teachers identified as contributing to their learning of the geometry content, many of which align with current recommendations for assessing and evaluating grade K-16 mathematics students.