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1.
In this paper, a logic computing model was constructed using a DNA nanoparticle, combined with color change technology of DNA/Au nanoparticle conjugates, and DNA computing. Several important technologies are utilized in this molecular computing model: DNA self-assembly, DNA/Au nanoparticle conjugation, and the color change resulting from Au nanoparticle aggregation. The simple logic computing model was realized by a color change, resulting from changing of DNA self-assembly. Based on this computing model, a set of operations computing model was also established, by which a simple logic problem was solved. To enlarge the applications of this logic nanocomputing system, a molecular detection method was developed for H1N1 virus gene detection.  相似文献   

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With the progress of DNA computing, DNA- based cryptography becomes an emerging interdisciplinary research field. In this paper, we present a novel DNA cryptography that takes advantage of DNA self assembled structure. Making use of the toehold strands recognition and strand displacement, the bit-wise exclusive-or (XOR) operation is carried out to fulfill the information encryption and decryption in the form of a one-time-pad. The security of this system mainly comes from the physical isolation and specificity of DNA molecules. The system is con- structed by using complex DNA self-assembly, in which technique of fluorescent detection is utilized to implement the signal processing. In the proposed DNA cryptography, the XOR operation at each bit is carried out individually, thus the encryption and decryption process could be con- ducted in a massive, parallel way. This work may dem- onstrate that DNA cryptography has the great potential applications in the field of inRwmation security.  相似文献   

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事物的认知过程是一个非常复杂的过程,粒计算是人工智能领域中的一种新理念和新方法。概要介绍了几种典型的认知模型,结合粒计算的方法论提出了基于粒计算的认知模型,并分析了图像认知过程中的粒计算方法和讨论了图像认知必须解决的关键问题。  相似文献   

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全错位排列问题是组合数学中的一类重要问题,可转化为范式的形式,利用自组装纳米颗粒探针对满足性问题进行求解。将纳米金颗粒和DNA序列进行结合,形成纳米金颗粒探针的识别区,并且成拱形结构。当识别区与其补链发生杂交反应时,拱形结构打开并发出荧光,从而给出了全错位排列问题的一种新的DNA计算模型。与传统的DNA计算模型不同,本文将纳米技术和DNA计算理论相结合。  相似文献   

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The essential characteristic of DNA computation is its massive parallelism in obtaining and managing information. With the develop- ment of molecular biology technique, the field of DNA computation has made a great progress. By using an advanced biochip technique, laboratory-on-a-chip, a new DNA computing model is presented in the paper to solve a simple timetabling problem, which is a special version of the optimization problems. It also plays an important role in education and other industries. With a simulated biological experiment, the result snggested that DNA comnutation with lab-on-a-chin has the notential to solve a real comtplex timetabling problem.  相似文献   

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针对当前的概念检索模型存在没有语义特征的词典和缺乏知识库层面上的推理机制等问题,采用具有很强的表达能力和可判定推理功能的描述逻辑来实现概念的扩展检索.设计了一个基于描述逻辑的概念检索模型,并对其核心的推理算法作了进一步扩展,给出了相应算法的数学定义及其知识库的逻辑描述,并据此采用Jena和Racer推理引擎实现了一个基于描述逻辑的汽车导购的概念检索系统,可向用户提供有关汽车的分类、性能、报价等信息.实验结果表明:基于描述逻辑的概念检索模型实现了有效的隐含语义的检索,并通过关联概念联想实现了良好的用户启发和信息导航.  相似文献   

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基于粒逻辑的扩展RBAC模型   总被引:3,自引:0,他引:3  
RBAC作为一种有效的访问控制模型已被广泛地研究和应用,但传统的RBAC模型没有考虑时间和上下文因素,角色之间、权限之间的逻辑关系比较简单,以至于在拥有大量用户和角色的系统的授权中表现出效率低、管理复杂等不足.为了解决以上问题.将粒计算的思想引入到RBAC模型中,提出了基于粒逻辑的G-RBAC模型,该模型将权限、角色粒化,在权限粒和角色粒上加入了时间和上下文的因素;基于粒逻辑,定义了G-RBAC模型中各元素间的逻辑运算,实现了G-RBAC的授权推理决策,提高了授权的灵活性.应用实例表明,G-RBAC模型能有效地实现大型系统的细粒度访问控制.  相似文献   

10.
借助可信计算的完整性检验、认证及访问控制和密封存储等关键技术,在可信计算平台的环境下,将可信计算平台与访问控制模型相结合,提出了一个基于可信计算的访问控制模型.该模型利用TPM实现用户和软件之间的相互认证,并通过身份映射的角色来控制不同用户对软件的使用权限.  相似文献   

11.
为了充分利用服务端存储模式计算机的非本地存储特性,该文提出了一种适用于服务端存储的可信计算模型。该模型通过把原有的可信平台模块硬件逻辑化为服务端软件模块,不仅降低了可信计算模型实施的难度,而且提高了其灵活性和扩展性。同时该模型从客户端系统的引导阶段出发构建完整的可信链,保证了可信计算平台的安全性。原型系统实现的结果表明:由于系统中所有客户端的信任度量均在服务端完成,使服务端能制定针对局域网全网的安全策略,进而实现真正的局域网网络可信。  相似文献   

12.
The essential characteristic of DNA computation is its massive parallelism in obtaining and managing information.With the development of molecular biology technique,the field of DNA computation has made a great progress.By using an advanced biochip technique,laboratory-on-a-chip,a new DNA computing model is presented in the paper to solve a simple timetabling problem,which is a special version ofthe optimization problems.It also plays an important role in education and other industries.With a simulated biological experiment,the result suggested that DNA computation with lab-on-a-chip has the potential to solve a real complex timetabling problem.  相似文献   

13.
为了刻画金融时间序列的尖峰厚尾性及股市中存在的杠杆效应,Ding、Granger和Engle(1993)提出了APARCH模型,但在关于此模型的研究中,通常假设条件分布为正态分布或对称厚尾分布,如t分布、GED分布.在兼顾波动性和分布两个方面的基础上对收益率序列建立APARCH-st模型,给出其VaR和ES的计算方法,并与基于APARCH-t模型的ES值相比较,结果表明,考虑偏态分布得到的ES估计更为保守.  相似文献   

14.
首先从具体实例入手抽象和归纳出质粒DNA计算模型的概念,并对质粒DNA计算模型计算体系的2个基本要素———计算物质和计算手段进行研究,由此形成了质粒DNA计算模型完备的计算体系;然后针对质粒DNA计算模型计算体系的应用,分析和解决了经常出现的关键问题.讨论了初始质粒DNA重新合成的重要性,并给出了重新合成的方法;接着对计算体系的2个基本实验(酶切和酶连实验)的成功率问题进行了分析,并提出了解决的方案;最后对检测实验进行了分析,提出了检测多种DNA序列的检测方法.对这些问题的分析和解决有利于质粒DNA计算模型理论的完善和应用的拓广.  相似文献   

15.
DNA计算是一种新的并行计算模式,在解决NP完全问题等方面具有很大的优越性.利用DNA计算的计算特性给出了一个图的k着色问题的DNA计算模型,该算法最多需要3kn(n-1)/2+6个生物操作即可求出图的色数及相应的着色模式.  相似文献   

16.
针对影视传媒专业使用计算机的频率高、容量大、设备更新快的特点,提出建立基于云计算的校园私有云的架构模式,进行基础实施层、基础平台层、服务平台层的分层架构设计,形成一个统一管理、统一服务的二级学院校园私有云平台与服务系统,有利于资源的合理利用,为单位自建私有云系统提供依据。  相似文献   

17.
DNA computing on surfaces   总被引:68,自引:0,他引:68  
Liu Q  Wang L  Frutos AG  Condon AE  Corn RM  Smith LM 《Nature》2000,403(6766):175-179
DNA computing was proposed as a means of solving a class of intractable computational problems in which the computing time can grow exponentially with problem size (the 'NP-complete' or non-deterministic polynomial time complete problems). The principle of the technique has been demonstrated experimentally for a simple example of the hamiltonian path problem (in this case, finding an airline flight path between several cities, such that each city is visited only once). DNA computational approaches to the solution of other problems have also been investigated. One technique involves the immobilization and manipulation of combinatorial mixtures of DNA on a support. A set of DNA molecules encoding all candidate solutions to the computational problem of interest is synthesized and attached to the surface. Successive cycles of hybridization operations and exonuclease digestion are used to identify and eliminate those members of the set that are not solutions. Upon completion of all the multistep cycles, the solution to the computational problem is identified using a polymerase chain reaction to amplify the remaining molecules, which are then hybridized to an addressed array. The advantages of this approach are its scalability and potential to be automated (the use of solid-phase formats simplifies the complex repetitive chemical processes, as has been demonstrated in DNA and protein synthesis). Here we report the use of this method to solve a NP-complete problem. We consider a small example of the satisfiability problem (SAT), in which the values of a set of boolean variables satisfying certain logical constraints are determined.  相似文献   

18.
基于可信计算思想提出了一个车联网云平台用户间的安全通信模型.该模型借助可信第三方,在申请通信服务过程中为车联网云用户生成临时身份,即对车联网云用户身份进行匿名化处理,以实现对用户身份隐私的保护.在通信过程中,该模型采用双线性对签名的算法分别对用户的身份合法性和平台可信性进行认证,并有效地使用了随机数、密钥和时间戳,以密钥和散列函数确保了签名的不可伪造性,以时间戳确保了密钥的时效性,以随机数机制防止了重放攻击.分析结果表明:在车联网云平台中采用该通信模型可以使通信过程具备可信性、安全性和匿名性.  相似文献   

19.
借鉴视觉系统的轮廓感知能力,提出了一种基于视觉神经计算模型的图像边缘检测新方法.首先构建以动态突触互连的双层神经元网络;接着建立了一种基于突触前神经元响应模式的脉冲传递模型,利用神经元的脉冲发放时空模式来凸显边缘空间信息;最后通过发放率灰度映射获取图像边缘信息.以包含较多弱对比度边缘的微生物显微图为例,以信息熵、边缘置信度和重构相似度做定量分析,结果表明所提方法能够有效实现弱对比度边缘检测,为视觉机制在图像处理中的应用提供崭新的思路.  相似文献   

20.
在基于P2P的分布式虚拟环境中,局部状态由普通节点计算和发布,因此计算和发布局部状态的节点如果选择不当就会引发欺骗问题.针对这一问题,提出了可扩展的单点代理计算(SPC)模型.在该模型中,通过选择利益无关的代理计算节点来负责每个节点的局部状态的计算和发布,从而实现了对应用层欺骗的预防.在SPC模型中,每"轮"内节点局部状态的计算和发布只需要三个应用层hop,节点加入或者退出只需要O(1)的通信量和O(1)的应用层hop数,而其系统通信量却只是C/S模型中系统通信量的3~4倍.  相似文献   

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