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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
针对基于HLA仿真应用系统开发中存在的计算模型程序与RTI服务程序的耦合问题,研究了基于共享内存和中断回调技术的解耦方法,进一步采用HLA仿真适配器对RTI服务程序进行封装,从而实现了计算模型程序与RTI底层服务程序的有效隔离。为提高仿真应用程序开发效率,分析了联邦成员中RTI服务程序功能需求,研究实现了仿真适配器自动生成软件。该软件可快速生成基于HLA的联邦成员适配器代码和执行程序,从而构建仿真应用系统分布式仿真框架。 相似文献
992.
993.
994.
PLC与组态王十字路口交通灯控制系统设计 总被引:1,自引:0,他引:1
使用欧姆龙PLC控制器设计十字路口交通灯控制系统。在设计硬件接线图与软件功能图的基础上,编写出相应的梯形图程序.采用CX—Programmer软件和Kingview 6.53组态软件进行模拟仿真。实验结果表明,该交通灯控制系统界面友好。运行正常,具有较好的控制效果。 相似文献
995.
996.
997.
Microstructure and Properties of Co2+ : ZnAl2 O4 /SiO2 Nanocomposite Glasses Prepared by Sol–Gel Method
Xiu-Lan Duan Duo-Rong Yuan Xiu-Feng Cheng Hai-Qing Sun Zhi-Hong Sun Xin-Qiang Wang Zeng-Mei Wang Dong Xu Meng-Kai Lv 《Journal of the American Ceramic Society》2005,88(2):399-403
Transparent bulk Co2+ : ZnAl2 O4 /SiO2 nanocomposites containing nanocrystalline Co2+ : ZnAl2 O4 dispersed in silica glass matrix were obtained by the sol–gel method. The gels of composition 89SiO2 –6Al2 O3 –5ZnO− x CoO ( x =0.2, 0.4, 0.6, 0.8, 1.0) (mol%) were prepared at room temperature by using two different aluminum salts, aluminum nitrate and aluminum alkoxide (aluminum-iso-propoxide, Al(OPri )3 ), as starting materials. The transparent gels were converted to the crystalline phase of gahnite by heating above 900°C. The microstructural evolution of gels was characterized. The effect of Co2+ concentration on spectroscopic properties was also discussed. Co2+ : ZnAl2 O4 nanocrystals dispersed in the SiO2 -based glass are formed at lower heat-treatment temperature and shorter heating time by using Al(OPri )3 as raw material. 相似文献
998.
999.
Relationship of structure to properties of surfactants. 16. Linear decyldiphenylether sulfonates 总被引:1,自引:0,他引:1
Milton J. Rosen Zhen Huo Zhu Xi Yuan Hua 《Journal of the American Oil Chemists' Society》1992,69(1):30-33
The properties of some well-characterized sodium linear decyldiphenylether (C10DPE)sulfonates have been studied. Among the properties investigated are dynamic and equilibrium surface tension, critical
micelle concentration (CMC), area per molecule at the aqueous solution/air interface, wetting time by the Draves technique,
foaming by the Ross-Miles method, solubilization, and hydrotropy. The decyldiphenylether moiety appears to be equivalent to
a terminally substituted straight alkyl chain of 16 carbon atoms. The trialkyl- and dialkyl-mono-sulfonates have solubilities
of < 0.01 g/dm3 in water, but are readily soluble in hexane. The didecyldiphenyl ether disulfonate (DADS) has a very low CMC value (1.0 ×
10−5 mol dm−3) in aqueous 0.1 N Na+ solution (NaCl), characteristic of surfactants with two hydrophilic and two hydrophobic groups. It also has a much larger
area per molecule at the aqueous solution/air interface than the monodecyldiphenyl-ether monosulfonate (MAMS) and a much higher
surface tension at the CMC. MAMS has a much lower surface tension at a surface age of 1 second (γ1s) than either DADS or the monodecyldiphenylether disulfonate (MADS). In agreement with γ1s and γeq values, wetting times increase in the order: MAMS < DADS < MADS and initial foam heights decrease in the order: MAMS > DADS
> MADS. Solubilization for three water-insoluble surfactants decreases in the order: DADS > MAMS > MADS, while hydrotropy
is most pronounced with the disulfonates. 相似文献
1000.
Construction of a key-dependent message secure symmetric encryption scheme in the ideal cipher model
Qiqi LAI Yuan CHEN Yupu HU Baocang WANG Mingming JIANG 《Frontiers of Computer Science in China》2014,(3):469-477
Key-dependent message (KDM) security is an important security issue that has attracted much research in recent years. In this paper, we present a new construction of the symmetric encryption scheme in the the ideal cipher model (ICM); we prove that our scheme is KDM secure against active attacks with respect to arbitrary polynomialtime challenge functions. Our main idea is to introduce a universal hash function (UHF) h as a random value for each encrypfion, and then use s = h(sk) as the key of the ideal cipher F, where sk is the private key of our symmetric encryption scheme. Although many other schemes that are secure against KDM attacks have already been proposed, in both the ideal standard models, the much more significance of our paper is the simplicity in which we implement KDM security against active attacks. 相似文献