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1.
带有预防接种的手机蓝牙病毒传播模型   总被引:1,自引:0,他引:1  
为了揭示手机蓝牙病毒的传播规律,以便更好地为制定病毒的预防措施提供理论依据,给出了移动环境下手机节点平均度的计算方法.提出了带有预防接种的手机蓝牙病毒传播模型,在模型中引入了手机蓝牙信号覆盖半径、节点分布密度、节点移动速度、比例因子和病毒复制时间等5个参数,讨论了各参数对病毒传播的影响.仿真实验表明,该模型较好地模拟了手机蓝牙病毒的传播过程,符合手机蓝牙病毒的传播规律.  相似文献   

2.
复杂网络理论的蓬勃发展为人们研究病毒传播行为和网络结构对病毒传播影响提供了新的思路,网络结构动态演化对病毒传播控制有着重要作用.考虑到有限资源约束,为及时有效地控制病毒传播,提出了一种与初始感染源无关的病毒传播控制策略:有限临时删边(Limited-Temporary-Links-Removed,LTLR)策略.该策略在保证网络系统基本功能不受影响的前提下,通过临时删除或管制网络中病毒传播最短路径上重要的边资源,使得病毒绕道或被阻断,从而有效地延缓病毒的传播速度和控制病毒的传播范围.仿真实验表明,在具有小世界特性的网络中,LTLR策略能显著增加网络平均路径长度、提高病毒传播控制效率,并且该策略消耗少、易于部署,可作为一类通用的优化控制策略推广到舆情网络传播控制、交通网络拥塞治理等领域.  相似文献   

3.
计算机网络在为人类造福的同时,也为病毒的传播提供了便利。在网络环境下,病毒传播的范围扩大了,速度大大加快,网络已成为近年来病毒传播的主要途径。针对病毒在网络上传播的新特点,分析了网络环境下病毒传播的主要模式,包括E-mail传播、主动扫描传播、通过服务器传播等,介绍了业界的一些对策,并给出了一般用户有针对性的应对措施。  相似文献   

4.
从计算机网络中节点感染和防御病毒的实际过程出发,提出了一种带有修复状态的计算机网络病毒传播模型,将感染后经过处理的节点划分为修复状态和免疫状态,通过微分方程组求解模型的稳态解,然后通过MATLAB仿真模拟分析理论值与仿真值的差别,校正所提出的模型.结果表明:该模型中感染率存在一个阈值,感染率小于阈值时,所有网络节点最终将被治愈,病毒消亡;反之病毒爆发.因此,控制感染率小于临界值将有利于抑制病毒的爆发.论文研究的结果有助于制定更加有利于抵制病毒传播的策略,维护网络的信息安全.  相似文献   

5.
从计算机网络中节点感染和防御病毒的实际过程出发,提出了一种带有修复状态的计算机网络病毒传播模型,将感染后经过处理的节点划分为修复状态和免疫状态,通过微分方程组求解模型的稳态解,然后通过MATLAB仿真模拟分析理论值与仿真值的差别,校正所提出的模型.结果表明:该模型中感染率存在一个阈值,感染率小于阈值时,所有网络节点最终将被治愈,病毒消亡;反之病毒爆发.因此,控制感染率小于临界值将有利于抑制病毒的爆发.论文研究的结果有助于制定更加有利于抵制病毒传播的策略,维护网络的信息安全.  相似文献   

6.
在网络中存在超强传染者的前提下,传统的病毒传播模型在无限规模的无标度网络上不存在病毒传播阈值,许多真实的无标度网络中并不存在这种超强传染者.针对这一问题提出了无标度网络中基于反馈机制的最大传染能力限定的病毒传播模型.通过数学方法证明了该模型中病毒传播阈值是存在的,最后通过数据仿真分析了反馈机制、最大传染能力值对网络感染率、控制病毒扩散以及传播阈值的影响.这为控制真实网络中的病毒传播提供了重要的参考依据  相似文献   

7.
在移动自组网(MANETs)领域,节点的移动特性导致网络拓扑结构动态变化,安全补丁无法在网络中快速传播,从而没有对移动自组网脉冲免疫下的病毒传播进行研究.对此考虑到MANETs脉冲免疫的现实可行性,建立MANETs病毒传播脉冲免疫模型.基于脉冲微分方程(Impulsive Differential Equations,IDE)稳定性理论分析脉冲免疫下的MANETs的病毒传播行为和病毒是否消亡的感染临界特性,并对该系统的无病(Disease-free,DF)周期解的存在性、稳定性以及地方病(Endemic,ED)的持续存在性加以分析.并选取相应的参数,对系统进行数值仿真,实验结果验证了所得结论的正确性与一致性.  相似文献   

8.
集中式信道分配算法在WSN移动节点中的应用研究   总被引:1,自引:1,他引:0  
为提高油料保障系统中信息采集的实时性和能量的高效性,使网关及时检测到移动设备的状态,降低无线网络间的干扰,提高网络的容量.以军用机场加油车为研究对象,提出了适用于快速移动节点的集中式信道分配算法和功率分级的能量控制方法.在无线网络节点上安装两个工作在不同频道上的网络接口,通过控制协商动态的切换数据信道,平衡网络负载,以增加总的带宽.实验结果表明,采用3条数据信道便可实现信道的集中式分配和发送功率的分级控制,有效地扩展了网络的容量和提高能量的高效性.  相似文献   

9.
网络免疫技术是抑制病毒传播的主要方法之一。本文针对当前网络病毒免疫策略未考虑的网络节点异质性,以及现实网络中免疫策略流行度问题。提出一种带有免疫策略流行度的策略研究方法,并将网络节点异质性考虑在内。通过建立无标度网络的病毒传播模型,研究网络节点异质性和免疫策略流行度,在控制网络病毒传播所起到作用。  相似文献   

10.
针对目前对等计算(P2P)网络中越来越严重的病毒传播和感染问题,结合生物免疫系统的工作原理和P2P网络自身的特点,提出一种新的P2P网络主动免疫联防模型.该模型将Peer节点局部免疫系统和以反病毒中心节点(ACP)主导的整体免疫防御体系有机结合在一起,从而对通过网络传播的恶意代码、病毒进行有效的、主动的控制和防御.详细的描述了P2P网络主动免疫联防模型的组成和运作流程,分析了模型中需要解决的关键问题,重点研究了ACP对病毒报告的应答机制和相应策略,并构建实验系统对此研究结果予以验证.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

20.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

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