Snort在电子商务网站安全方面的应用

分析了目前主要针对电子商务网站的攻击在系统中的各种表现以及危害,介绍了免费开源的入侵检测阻挡系统Snort的特性,指出可以通过启用Snort嵌入模式,应用规则文件来提高网站的安全性.     

水轮机调速器参数自整定遗传算法的研究

水轮机调速器的参数整定直接关系到水轮机调节系统的稳定运行及调节品质，进而会影响到电能的质量.应用可变交叉概率和变异概率的改进遗传算法对水轮机PID调速器参数进行优化，并将改进遗传算法的计算结果进行仿真分析，结果表明，该方法有效地消除了对参数初值的依赖性，使得寻优效率大大提高，改善了收敛性，是一种较好的PID参数寻优方法。     

狗经氡子体暴露后血、毛中~(210)Pb 和~(210)Po 含量的动态变化

本文叙述了实验狗经氡子体暴露后血、毛中~(210)Po、~(210)Pb 含量、~(210)po/~(210)Pb 比率及血中~(210)Po,~(210)Pb 排出的动态变化。     

A new method of characterization for stratified thermal energy stores

A new method for characterization of stratified thermal energy stores (TES) that integrates both the first law and the second law concerns is presented here. The first law concern is incorporated into a quantity called energy response factor and the second law concern into an entropy generation ratio. A product of these two quantities is at the heart of the TES efficiency definitions. This approach removes the overemphasis of the existing methods either on the first or the second law of thermodynamics which often biases the characterization results. The information about the evolution of the temperature field of the system in time is the prerequisite of the new method. It may be obtained from experiments or from suitable numerical simulations. The current method can be easily integrated into computational fluid dynamic (CFD) simulations and thus facilitate CFD-based design analysis. As an example of such CFD-integrated analysis, a large-scale hot water seasonal heat store is numerically studied to identify the effects of aspect ratio, containment shape, internal structures, and containment size on their efficiency. The results suggest the effectiveness of the new method in deriving useful design insights.     

Some characteristics and a comparison 6f the activities of o-dihydroxyphenoloxidase activity from five yam (Dioscorea spp.) species

o-Dihydroxyphenoloxidase (E.C. 1.14.18.1) (o-DPOase) was extracted from acetone-extracted freeze-dried yam tubers, and fractionated by (NH₄)₂SO₄ precipitation and chromatography on DEAE-cellulose to give two forms from Dioscorea alta L. (cv. UM680) and three forms from D. rotundata Poir. (cv. Nwopoke). Polyacrylamide gel electrophoresis revealed one of the forms from each species to contain two protein bands with o-DPOase activity. o-DPOase from D. alata showed activity with catechol, (+)-catechin, (?)-epicatechin and chlorogenic acid, but not with tyrosine, as substrate, o-DPOase from D. rotundata showed activity only with catechol and (+)-catechin. K_m values for D. rotundata enzymes, calculated assuming a two-substrate reaction, were between 0.2 and 0.8 mM for oxygen and 70 and 120 mM for catechol. The enzyme was most active between pH 5.5 and pH 7.0, and showed slight activation after holding for 2 minutes at 40 or 50°C. After heating to above 60°C the enzyme showed evidence of irreversible denaturation. Theo-DPOase activity extracted from ten cultivars of five species of D. alata L., D. bulbifera L., D. cayenensis Lam., D. dumetorum Pax, and D. rotundata Poir. were compared.     

论GPS星座组成及若干抗AS方案

本文首先讨论GPS星座组成及美国的用政策，阐述了AS措施及其对GPS测量的影响。然后，对抗AS的若干方案进行介绍，分别对平方法、互相关法、码相关干法及P－W技术（Ashtech法）进行叙述和评论，指出它们的优缺点，评述它们在GPS技术发展过程所起的作用。最后，对GPS星座建成后的形势作了小结，并对当前我国GPS事业的有关问题提出四点建议。     

多孔硅发光机制的分析

从量子力学的基本理论出发讨论了量子限制效应，推导出多孔硅有效禁带宽度增量并用量子限制效应和表面态及其物质在发光中作用的理论解释了ＰＳ光致发光的实验现象。     

无染色牛肝过氧化氢酶薄晶的图象处理

本文根据Ｐ．Ｎ．Ｔ．Ｕｎｗｉｎ和Ｒ．Ｈｅｎｄｅｒｓｏｎ等人提出的对生物大分子晶体的囹象处理方法，对无染色的牛肝过氧化氢酶薄晶的显微象和衍射图进行了图象处理，最后得到了牛肝过氧化氢酶薄晶的二维结构。从中可以看出，牛肝过氧化氢酶薄晶的一个单胞由４个子胞组成，４个子胞排列方向各异。     

电子通道技术在YBa2Cu3O7外延超导薄膜研究中的应用

本研究采用电子通道技术（ＥＣＰ）对单晶和双晶外延生长的ＹＢａ＿２Ｃｕ＿３Ｏ＿７（ＹＢＣＯ）超导薄膜的结构、取向和表面完好性作检测，并证实对衬底的预处理可改善外延超导薄膜的质量；还对ＹＢＣＯ／ＣｅＯ＿２／ＭｇＯ／ＳｒＴｉＯ３的双外延薄膜作研究。