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具有对称结构的FFT算法 总被引:1,自引:0,他引:1
利用离散付里叶变换的对称性质,本文提出了一种使FFT流图具有称性质的FFT算法,该算法的实现流图中输入和输出序列均为自然排列顺序,其流图表达简明。该算法的矩阵表达式比基-2FFT的矩阵表达式更为简明,并减少一倍的矩阵形式.在某些特殊场合下.可以使指令形式大为减少。 相似文献
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基于可控随机变换的分形树生成算法及实现 总被引:2,自引:0,他引:2
分形树的生成算法是自然景物模拟中的热点问题,针对目前生成算法中的运行显示速度慢,树形变化少,颜色单一等问题,提出了一种可控随机交换的分形树生成算法.该算法对分形树的生成参数进行随机控制.给出了该算法的核心思想及实现过程,仿真实验得到了较好的生成显示速度及多姿态、多色彩的具有三维真实感的分形树.算法具有一定的通用性并可为其他自然景物的模拟提供较高的研究参考价值. 相似文献
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为了给C语言编程题进行合理评分,本文提出了一种新型的自动评分方法,在动态检测阶段先利用KMP算法执行关键字匹配,若匹配相似度落入预期值区间,则将学生源程序转换为可执行文件,通过预先设置的测试用例来驱动评分;若关键字匹配未通过、程序无法运行或者运行期间出现异常,则执行静态分析.静态分析阶段选取控制结构作为静态评分的关键因素,采用抽象语法树作为源代码的中间转换形式,并对其标准化以消除代码语义的多样性;根据抽象语法树中的结点类型提取出控制结构子树;最后,利用基于结点权值的树编辑距离算法来匹配标准化后的学生源程序与模板程序的控制结构子树,计算相似度并给出综合评分结果.实验结果表明,该方法能够对程序进行合理有效地评分,并且具有较高的准确率. 相似文献
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混合图的有向k树多项式的产生和状态空间树 总被引:5,自引:0,他引:5
引入了混合图G的有向K树多项式P(t_(F_1),……F_K)的状态空间树T的概念和算法SSTDKTP。提出了用分支-定界法产生P(t_(F_1),……,F_K)的一个新算法——算法DKTPCG。该算法简单,所得表达式十分紧凑。计算时间复杂度是O(men_l);空间复杂度对于堆栈是O[(n-k)(ke+n)],对于输出数组XE,YE,FL和NS是O(n_(df)),这里n_l和n_(df)分别是T的叶点和状态节点的数目。 相似文献
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提出一种基于矩阵的DBSCAN算法中核心点分类的新方法,说明该方法相比较R*-树具有较好的数学表述形式,仿真实验证明该方法较原DBSCAN算法,当数据量不大时具有较好的时效性。 相似文献
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本文研究了不确定型模糊Kripke结构的计算树逻辑的模型检测问题,并说明了该问题可以在对数多形式时间内解决.首先给出了不确定型模糊Kripke结构的定义,引入了模糊计算树逻辑的语法和语义.为了刻画存在量词∃和任意量词∀在不确定型模糊Kripke结构中的两种语义解释,在模糊计算树逻辑语法中引入了路径量词∃sup,∃inf和∀sup,∀inf,分别用于替换存在量词∃和任意量词∀.其次讨论了基于不确定型模糊Kripke结构的计算树逻辑模型检测算法,特别地对于模糊计算树逻辑公式∃suppUq,∀suppUq,∃infpUq和∀infpUq分别给出时间复杂度为对数多项式时间的改进算法. 相似文献
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Based on the growing demand for neural network technologies, various neural network inference engines are being developed. However, each inference engine has its own neural network storage format. There is a growing demand for standardization to solve this problem. This study presents interworking techniques for ensuring the compatibility of neural networks and data among the various deep learning frameworks. The proposed technique standardizes the graphic expression grammar and learning data storage format using the Neural Network Exchange Format (NNEF) of Khronos. The proposed converter includes a lexical, syntax, and parser. This NNEF parser converts neural network information into a parsing tree and quantizes data. To validate the proposed system, we verified that MNIST is immediately executed by importing AlexNet's neural network and learned data. Therefore, this study contributes an efficient design technique for a converter that can execute a neural network and learned data in various frameworks regardless of the storage format of each framework. 相似文献
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tree是web开发中比较常用的展示控件,用来显示信息的分级视图,具有层次分明,表意清晰的特点。因此许多web插件中都包含tree,例如ExtJS、JQuery UI和easy UI,它们有一个共同的特点就是数据格式都是json,并且由于树分层的特性使得json数据还会嵌套多层。而在关系型数据库中取出的sql结果集却往往不能友好地支持这种分层的json格式。本文根据具有树形结构的数据在数据库中存储的方式以及其与json数据之间的复杂映射关系,提出一种sql结果集到json数据的转换算法。 相似文献
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1 IntroductionInthepastthirtyyears,randomaccesstech niqueshavewidelybeenappliedinsatellitesystems,groundradionetworks,andcomputerandcommuni cationsystems.TheoriginalrandomaccessschemewasALOHAsystemwhichwasintroducedbyAbramsonin 1 970 .Thissystemschemewassim… 相似文献
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Instructions for operating a control panel were presented in five different formats: flowchart, logical tree, yes/no tree, decision table, and list. Subjects had to choose one out of eight buttons, depending on the settings of the control panel. The results show that the decision table resulted in more errors, and that both the decision table and the list took longer than the three other formats, which did not show mutual differences. It turned out that the subjects valued most the format they had been using, except for those who had worked with the list. It is suggested that the users' ease of orientation for a diagram's format, both during reading and after “switching” between equipment and instructional text, explains the differences between the formats 相似文献
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商品价格数据的两种WEB挖掘算法比较 总被引:1,自引:0,他引:1
其他网络商店的商品实时价格是Web商店店主所关注的重要数据,Web数据挖掘使得这一需求变为现实.通过正则表达式算法与分词算法的比较研究,给出了基于正则表达式的商品价格抽取算法和基于分词的网站目录树抽取算法、HTML网页商品抽取算法与商品价格抽取算法.应用系统的实践表明,正则表达式算法的挖全率与正确率较低,而分词算法的挖全率与正确率都达到99%以上,完全满足应用需求,同时可以为商品的市场预测与分析提供依据. 相似文献
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En-Hui Yang Kieffer J.C. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》2000,46(3):755-777
A grammar transform is a transformation that converts any data sequence to be compressed into a grammar from which the original data sequence can be fully reconstructed. In a grammar-based code, a data sequence is first converted into a grammar by a grammar transform and then losslessly encoded. In this paper, a greedy grammar transform is first presented; this grammar transform constructs sequentially a sequence of irreducible grammars from which the original data sequence can be recovered incrementally. Based on this grammar transform, three universal lossless data compression algorithms, a sequential algorithm, an improved sequential algorithm, and a hierarchical algorithm, are then developed. These algorithms combine the power of arithmetic coding with that of string matching. It is shown that these algorithms are all universal in the sense that they can achieve asymptotically the entropy rate of any stationary, ergodic source. Moreover, it is proved that their worst case redundancies among all individual sequences of length n are upper-bounded by c log log n/log n, where c is a constant. Simulation results show that the proposed algorithms outperform the Unix Compress and Gzip algorithms, which are based on LZ78 and LZ77, respectively 相似文献
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基于基础seq2seq深度学习算法在语法纠错准确率和召回率方面存在的不足,提出了融合Attention机制和Transformer模块的改进型seq2seq语法纠错算法。通过引入Attention机制来记录decoder端和encoder端语言信息,提升信息完整性,采用beam-search和copy机制进行启发式搜索,缓解解空间对机器内存的消耗,利用Transformer模块进行自注意力机制的特征抽取,实现了语句向量数据的扩充并得到可解析上下文纠错。最后选择合适的语料库,对不同的语法纠错算法的准确率、召唤率和F 0.5数据语法纠错效果评价指标进行了比较,结果表明了文中改进的算法模型的有效性,提高了语法纠错的准确率和召回率。 相似文献