基于单轮循环结构的SMS4加密芯片的研究与设计

文章在分析SMS4原理的基础上提出了一种基于单轮循环结构的SMS4加密方案,通过复用单一的加密单元,经过32次循环迭代完成加密,大大减少了硬件资源的使用。该设计的开发平台是Altera公司的Quartus II 9.0,使用的FPGA(Field-Programmable Gate Array)开发板是Cyclone II EP2C8Q208C8。运行结果表明,SMS4加密芯片使用了5 268个逻辑单元和139 264位存储器资源,系统的时钟频率可以达到51.35 MHz,信息加/解密的峰值速度为3.2Gb/s,系统功耗为132.30 m W。

Temperature Effect on the Life History of Three Types of Brachionus calyciflorus Females

The effect of temperature on the life history characteristics of amictic females (AF), unfertilized mictic females (UMF) and fertilized mictic females (FMF) in Brachionus calyciflorus was studied with replicated individual cultures at 20℃,25℃ and 30℃, and with algae Scenedesmus obliquus for their food. There were highly significant effects of both temperature and female type, independently and interactively, on the duration of juvenile and post-reproduction periods, and the number of eggs produced by the rotifer per life cycle. Among all the temperature-female type combinations, all the juvenile periods of FMF, and the post-reproduction periods of UMF and FMF at 20℃, were the longest, and the number of eggs produced by an UMF at 30℃ was the highest. There were highly significant effects of both temperature and female type on the duration of the reproduction period, but no clear correlation was observed between temperature and female type. The reproduction period of AF was longer than that of UMF and FMF. Only temperature influenced significantly the mean life-span of the three types of females. The duration of juvenile, reproduction and post-reproduction periods as well as the life-span of the three types of females were all reduced very significantly with rise of temperature, but the rates of reduction varied with female type. Among the three types of females, the number of eggs produced per life cycle by an UMF was the highest, and that of a FMF was the lowest. A significant relationship between the number of eggs produced per life cycle and temperature was observed only in the UMF.