摘要:In this paper, a predator (wolves)-prey (deer) ecosystem model was established , and the stability of the system was ana-lyzed.%本文建立了捕食者(狼)-食饵(鹿)生态系统模型,并对其系统进行稳定性分析和研究。
摘要:The crashworthiness design of end energy -absorbing structure is a key of passive safety design for stainless steel subway . Based on the crashworthiness design concept of subway vehicle , the design of whole-load type dedicated absorbing structure in the end structure of vehicle was introduced .Numerical simulation of block trains collision is conducted by the finite element model of frontal and middle car-body.During the process of impacting , stable and ordered plastic deformation occurs on the whole -load type dedicated ab-sorbing structure .47%of impacting energy dissipates due to the plastic deformation of the dedicated absorbing structure .Results show that the car-body conform the crashworthiness design concept .%针对地铁车特点进行不锈钢地铁车被动安全设计时难点之一是其端部吸能结构的耐撞性设计。本文依据地铁车体耐撞性设计理念,在车体端部结构中设计整体承载式专用吸能结构。建立头车及中间车车体有限元模型,进行编组列车的碰撞数值仿真。研究结果表明:整体承载式专用吸能结构在撞击过程中发生稳定有序的塑性变形,冲击能量的47%转化为专用吸能结构的塑性变形,表明该车的耐撞性符合设计理念。
摘要:本文依据高性能中英文语音合成模块XFS4243CE,研制一款适用于家居的防盗语音报警系统。系统利用前端用超声波收发器完成防盗信息的检测,防盗信号经主控单片机C8051F410-GQ识别处理后,由后端XFS4243CE模块发出报警语音。整个系统较精简,性价比高。将语音合成技术嵌入报警系统中,使得该系统比传统的家居报警系统具有无法比拟的优势[1]。%On the basis of the high-performance Chinese -English speech synthesis module XFS 4243CE, a home voice burglar alarm system was developed .In the front of the system , the ultrasonic transceiver completed burglar information detection , and the anti-theft signal is recognized and processed by the host micro controller C 8051F410 -GQ, then the alarm voice is issued by the module XFS4243CE.The whole system is extremely streamlined , cost-effective, and the high-end speech synthesis technology is embedded in the system.Therefore it has incomparable advantages compared with the traditional home alarm system .
摘要:本文通过对东北粗皮蛙29个样本线粒体DNA控制区和细胞色素b基因部分序列分析,探讨其遗传多样性和种群遗传结构。 PCR扩增和测序结果,获得587bp的线粒体DNA控制区序列和895bp的细胞色素b基因序列。合并线粒体DNA序列分析,共定义14个单倍型,16个变异位点,单倍型多样性(H)为0.704,核苷酸多样性(π)为0.001,平均核苷酸差异数为1.438,表明东北粗皮蛙遗传多样性较低。分子变异分析(AMOVA)结果表明,种群内变异占全部遗传变异的98.13%,群体间没有遗传分化(FST =0.0187),因此应加强对东北粗皮蛙野生种群的保护。%The partial sequences of mitochondrial DNA control region and cytochrome b gene from 29 individuals were studied via PCR and sequencing, to investigate the genetic structure and genetic diversity of Rugosa emeljanowi.We obtained 587bp from mitochondrial DNA control region and 895bp from cytochrome b gene.Based on the analysis of coalescent data , 16 polymorphic sites were found and 14 haplotypes were detected .Haplotype diversity, nucleotide diversity and average number of nucleotide differences were 0.704, 0.001 and 1.438, respectively.These results showed that there was a lower genetic diversity among the population of Rugosa emeljanovi.Ac-cording to analysis of molecular variance (AMOVA), the genetic variation within populations was very high , being 98.13 %.The ge-netic differentiation between populations was not significant (FST=0.0187).The results suggested that we need to strengthen the con-servation for populations of Rugosa emeljanovi.