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1.
梁勇强  钟艳如 《计算机工程与设计》2007,28(14):3302-3305,3309
在基于割集的拆卸序列生成算法中,对拆卸操作的几何可行性进行判别是频繁的操作.引进有序二叉决策图OBDD合理表示拆卸约束,设计了基于OBDD的几何可行性判别算法,比较了基于OBDD的判别算法与基于移动函数的判别算法的时间复杂度,结果表明基于OBDD的几何可行性判别算法比基于移动函数的判别算法具有更高的判别效率.  相似文献   

2.
李继中  蒋烈辉  舒辉  常瑞 《计算机应用》2014,34(4):1025-1028
二进制代码中的密码算法识别与筛选对于恶意软件分析、密码算法应用安全性验证有着重要意义。分析了密码函数代码实现中内存数据操作特征和基本块循环结构特征,根据二进制数据的信息熵理论,实验验证了密码算法内存操作数据的高熵值特性,构建了基于动态循环信息熵的密码函数筛选模型,并采用动静结合的方法重构基本块循环中的动态读写内存数据。测试结果表明了筛选模型的可靠性和准确性。  相似文献   

3.
基于先验的图像去雾算法依赖于大气散射模型,易受环境影响出现去雾不彻底、颜色失真等现象,针对上述问题本文基于深度学习,提出一种多尺度密集感受域的GAN图像去雾算法。首先构建一个多尺度学习的生成器网络,通过3种不同尺度提取图像的局部细节和全局信息后进行特征融合;然后通过感受密集块来增大感受野并获得丰富的上下文信息,将提取到的特征图在多个感受密集块中对特征进一步细化;接着使用一个多尺度的GAN判别器,由2个相同的子判别器D1和D2组成,2个子判别器联合指导生成器的训练;最后本文结合L1损失、感知损失和对抗损失,设计一个多元损失函数来收敛网络。在SOTS测试集上进行主观评价和客观评价,实验结果表明,本文算法取得了较优的效果,有效改善去雾不彻底的现象。  相似文献   

4.
王佳欣  冯毅  由睿 《计算机应用》2019,39(6):1719-1727
管理人员通常使用一些网络安全指标作为度量网络安全的重要依据。通用漏洞评分系统(CVSS)是目前人们普遍认同的网络度量方式之一。针对现有的基于CVSS的网络安全度量无法精确测量网络受到攻击的概率和影响两方面得分的问题,提出一种基于依赖关系图和CVSS的改进基础度量算法。首先发掘攻击图中漏洞节点的依赖关系,构建依赖关系图;然后根据依赖关系修改CVSS中漏洞的基础度量算法;最后聚合整个攻击图中的漏洞得分,得到网络受到攻击的概率及影响两方面的得分。采用模拟攻击者进行仿真实验,结果表明,该算法在算法精确度和可信度方面明显优于汇总CVSS分数算法,更加接近实际仿真结果。  相似文献   

5.
布尔函数是密码体制设计与分析中一个不可缺少的工具,在布尔函数的应用中,判定两个布尔函数的同构问题具有广泛的需求,但是,判定布尔函数同构是NP-难问题,并且采取穷举法也将随着变量的增多,因极高的时间复杂度而使其难以实现.该文基于图的思想,提出了一种基于ROBDD(简化有序二元决策图)的布尔函数同构判定算法,其算法的复杂度...  相似文献   

6.
在布尔函数的设计中,总是希望得到满足多个密码特性的密码函数,但是这些密码特性之间存在着一定的制约关系。利用爬山算法对一阶相关免疫函数进行了优化,得到了大量高非线性度的布尔函数并通过MATLAB 实验对八元、九元一阶相关免疫函数进行了优化。实验结果表明,该算法可进一步优化相关免疫函数的非线性度。  相似文献   

7.
刘鹏  赵荣彩  庞建民  姚远 《软件学报》2014,25(11):2486-2498
指针分析是数据流分析中的关键性技术,其分析结果是编译优化和程序变换的基础。在基于包含的指针分析算法研究的基础上,对 Narse 优先权约束评估算法中存在的冗余约束评估和优先权评估模型计算开销较大的问题进行分析,以指针的指向集更新信息确定约束评估的候选集,提出了基于指向更新的约束评估算法。采用约束语句间的解,引用依赖和标量依赖构建约束依赖图,通过依赖关系确定约束评估的优先权,提出了基于约束依赖图的优先权算法,简化了既有算法中复杂的优先权评估模型,进一步给出了优化后算法的整体框架。在基准测试集 SPEC 2000/SPEC 2006上进行实验,其结果表明,该算法与Narse优先权算法相比,在时间开销和存储开销上都有明显的性能提升。  相似文献   

8.
对称密码算法专用描述语言(svLSCa)以自然的类似专业语言的思维方式描述算法的设计思想。在密码算 法设计中,对于已经证明安全性高的、性能良好的密码构件会重复采用,比如s变换、P置换等。在分析大量公开密码 算法设计特点和规律的基础上,在svLSCa语法中增加函数机制。详细给出了svLSCa中函数的定义、调用以及实 现的关键技术。并以AEC为例,说明函数在算法描述的应用。实践表明利用SDLSCA中函数的功能,可以大大简化 算法描述,提高算法描述的利用率和效率。  相似文献   

9.
随机函数及其在密码学中的应用研究   总被引:5,自引:1,他引:4  
王勇 《信息网络安全》2012,(3):17-18,24
文章提出了随机函数的概念,并且分析了现有密码算法的安全局限性,指出采用随机函数的密码算法具有很强的安全性优势,并且简要说明了采用随机函数来构造对称密码算法和hash函数的方法。  相似文献   

10.
针对海量论文数据导致的应用效率低下问题,提出一个基于层次混合模型的推荐算法WSVD++。该模型根据学术论文良好的结构特征,构建一个加权的论文二部图模型。首先对论文进行特征提取,按不同特征的权重构建论文的复合关系图;其次对关系图采用一种改进的PPR算法,计算每篇论文的重要程度,依此来对用户—论文关系进行加权;然后在构建好的加权二部图模型上混合SVD++图算法进行推荐。实验结果表明,改善了推荐算法学术论文的推荐效果,并且基于分布式图计算框架GraphX,扩展性好,适合大数据处理。  相似文献   

11.
Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.  相似文献   

12.
European Community policy and the market   总被引:1,自引:0,他引:1  
Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.  相似文献   

13.
融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。  相似文献   

14.
Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.  相似文献   

15.
This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.  相似文献   

16.
Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008  相似文献   

17.
为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.  相似文献   

18.
《计算机科学》2007,34(4):148-148
Recent years have seen rapid advances in various grid-related technologies, middleware, and applications. The GCC conference has become one of the largest scientific events worldwide in grid and cooperative computing. The 6th international conference on grid and cooperative computing (GCC2007) Sponsored by China Computer Federation (CCF),Institute of Computing Technology, Chinese Academy of Sciences (ICT) and Xinjiang University ,and in Cooperation with IEEE Computer Soceity ,is to be held from August 16 to 18, 2007 in Urumchi, Xinjiang, China.  相似文献   

19.
Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.  相似文献   

20.
This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)SM and Team Software Process (TSP){SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.  相似文献   

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