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1.
在网络空间安全领域,一个协议可以把自己伪装成其他协议达到避免被发现或者逃避监管的目的.借鉴生物拟态的机制,提出网络协议拟态系统的技术框架.该框架由协议拟态客户端和网桥两部分组成,其中协议拟态客户端包括环境感知、拟态决策、拟态实施处理、发送和接收处理5个部分;网桥分为环境感知、数据接收、恢复和发送4个部分.全面研究和评估已有的几个具有拟态特征的协议,包括SkypeMorgh、StegoTorus、CensorSpoofer及Format-TransformingEncryption系统,从认证机制、拟态变换和加密技术及流量控制技术等方面进行对比和分析,提出协议拟态的基本科学问题供进一步研究.  相似文献   
2.
借鉴生物遗传进化现象,将遗传算法引入拟态蜜罐系统中,提出了基于自适应遗传算法的拟态蜜罐演化策略,详细讨论了拟态蜜罐系统演化中特征形式化编码、遗传算子设计、适应度函数、演化触发控制与终止条件等关键问题,设计实现了具有自适应遗传演化功能的拟态蜜罐原型系统并进行了原型测试,实验数据表明了基于自适应遗传算法的拟态蜜罐演化策略具有良好的自适应性和有效性.  相似文献   
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Various species of treehoppers possess a structure known as ‘helmet’ that may work as a camouflage feature (i.e. masquerade) by mimicking plant thorns. The helmet is expected to provide an adaptive advantage against predators if treehoppers choose to stay closer to thorns during times of vulnerability. The treehopper Enchenopa brasiliensis Strümpel possess a helmet that visually resembles the leaf thorns of its host plant, the wolf apple shrub Solanum lycocarpum St. Hill. In a field study, I examined the hypothesis that females of E. brasiliensis exhibit a potential camouflage behaviour by choosing to oviposit next to leaf thorns of S. lycocarpum. In fact, the results reveal that females of E. brasiliensis preferred to oviposit mostly on leaf midribs of S. lycocarpum possessing thorns as opposed to those without thorns. Additionally, females preferred to lay eggs closer to larger clusters of midrib thorns. This finding suggests that this oviposition/camouflage behaviour will likely increase the chances of female treehoppers being misidentified by predators; therefore, characterizing the mechanism of masquerade/deceptive resemblance. In a broader sense, this study also provides further evidence on how the narrow ecological relationships between plants and specialist herbivores can fuel the evolution of specific behavioural adaptations.  相似文献   
5.
《Journal of Natural History》2012,46(25-28):1659-1678
Jumping spiders (Salticidae) are known for their elaborate vision‐based display behaviour, and a sizeable minority of the species in this large family resemble ants. The display repertoire of two ant‐like salticid species from the Philippines is investigated. Myrmarachne assimilis is a specialist ant mimic, closely matching the appearance of the weaver ant Oecophylla smaragdina. Myrmarachne bakeri is a generalist mimic, which, although ant‐like, is not a close match to any sympatric ant species. Myrmarachne are sexually dimorphic, with males having enlarged chelicerae. The copulatory posture of Myrmarachne is unique among salticids, apparently as an adjustment for the male's elongated chelicerae. Details concerning the intraspecific behaviour of Myrmarachne appear to be adjustments to living in environments populated by numerous other animals with similar appearance (ants). However, the specialist and the generalist that were investigated have display repertoires that are broadly similar to each other and to those of more typical salticids. Generally, the display behaviour of Myrmarachne appears not to have necessitated dramatic deviation from typical salticid display and mating strategies.  相似文献   
6.
WesternBlot实验证实了结核分枝杆菌(Mycobacteriumtuberculosis)H37Ra的单克隆抗体与自身抗原组蛋白发生免疫交叉反应.利用计算机软件对交叉反应的分子生物学基础进行了分析,发现结核分枝杆菌H37Ra的蛋白与组蛋白H1,H2A,H2B,H3,H4各有一个包含3个或4个氨基酸的序列同源区域.  相似文献   
7.
黄大仙信仰从产生之初便不断被地方化,尤其是进入岭南之后与岭南地域文化发生的互动更使地方化得到加强.东莞企石黄大仙的攀附与重构表明了这样一种倾向:处于边缘地位的地方黄大仙传说不断攀附被认为作为中心的香港黄大仙,并力图与之建立关系,扩大自身影响以吸引信众,攀附成为某种正统性的要求.由于文化与历史资源尚浅,经济弱势的企石黄大仙古庙必须借用外界的文化资源来建构自身的合法性.  相似文献   
8.
复杂目标外形拟合及散射截面计算   总被引:4,自引:0,他引:4  
本文用修正的双三次参数样条拟合目标外形,可直接使用飞机外形CAD设计数据库,可拟合绕射点坐标,主曲率半径及主方向,短程线及其它一些几何参数,用一致几何绕射理论计算目标的雷达散射截面。计算精度为1dB左右,理论计算与实验结果吻合好。  相似文献   
9.
Females of the aphid parasitoidParalipsis enervis received liquid food by regurgitation (trophallaxis) from workers of the ant speciesLasius niger, but were not fed by workers ofMyrmica laevinodis andTetramorium caespitum. WhileP. enervis was not treated aggressively by workers of any of these species,Lasius flavus workers killed the parasitoid. This different ant behaviour resulted in a different parasitoid longevity. WhileP. enervis survived for only 10 min in the presence ofL. flavus (due to ant aggression) or for approximately one day in the presence ofT. caespitum andM. laevinodis (due to lack of trophallaxis), survival increased significantly to more than five days in the presence ofL. niger, which provided food regularly to the parasitoids. Our study suggests thatP. enervis mimics behavioural signals ofL. niger, as well as odor cues of its host aphidAnoecia corni, to avoid aggression byL. niger.  相似文献   
10.
观察空间诱变后恶性黑色素瘤B16细胞株的在小鼠体内肿瘤组织中血管生成拟态数目的改变,并探讨可能的机理。应用细胞低温长期生存系统,将B16细胞株搭载于中国第20号返回式卫星,返地后单克隆化,从得到的110株单克隆空间诱变B16细胞株中随机选取7株,编号为38#~44#,常规培养6代后和对照细胞株在荧光倒置显微镜下观察肿瘤细胞的形态;同时采用MTT(3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide,又称噻唑蓝)法,检测细胞增殖情况,将增殖差异较大的39#和44#细胞株接皮下种于C57BL/6J小鼠,两周后颈椎脱臼法处死小鼠,取出瘤体,经福尔马林固定后,采用CD31和PAS套染的方法观测肿瘤组织血管生成拟态的情况,并推测其与肿瘤生长速度和转移可能关系。  相似文献   
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