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A Diagnostic Approach to Diseases in Pig's Respiratory System Based upon SVM Binary Tree 被引量:3
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作者 文斌 徐顺来 罗爱民 《Agricultural Science & Technology》 CAS 2011年第3期394-396,399,共4页
[Objective]To study a diagnostic approach to diseases in pig's respiratory system based upon SVM binary tree. [Method] First with the help of clustering theory,the degree of separation based upon the characteristics ... [Objective]To study a diagnostic approach to diseases in pig's respiratory system based upon SVM binary tree. [Method] First with the help of clustering theory,the degree of separation based upon the characteristics of diseases is defined. Each time the type of highest degree of separation is isolated to get a decision tree with smaller accumulated errors and SVM binary tree is applied in the diagnostic experiment of four common respiratory diseases. [Result] The method is practicable and can be applied in the diagnosis of pig's respiratory diseases at the early stage. [Conclusion] It provides references to the healthy development of pig husbandry in China and increases in breeders' incomes. 展开更多
关键词 SVM binary tree Respiratory diseases Disease diagnosis
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Binary Tree Petersen网络性质及算法研究
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作者 纪鸿飞 马英红 《山东师范大学学报(自然科学版)》 CAS 2010年第1期26-28,38,共4页
基于Petersen图,提出了Binary Tree Petersen的网络结构,并对其特性进行了研究,证明了Binary Tree Petersen网络具有正则性以及良好的可扩展性,同时还具有比RP(k)、2-DToms更短的直径和良好的并行能力.另外,还基于Binary Tree P... 基于Petersen图,提出了Binary Tree Petersen的网络结构,并对其特性进行了研究,证明了Binary Tree Petersen网络具有正则性以及良好的可扩展性,同时还具有比RP(k)、2-DToms更短的直径和良好的并行能力.另外,还基于Binary Tree Petersen网络分别给出了其上的单播和广播路由算法,证明了通信效率都为2j+4. 展开更多
关键词 PETERSEN图 binary tree Petersen网络 路由算法
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An Assessment of Snow Cover Duration Variability Among Three Basins of Songhua River in Northeast China Using Binary Decision Tree 被引量:1
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作者 YANG Qian SONG Kaishan +2 位作者 HAO Xiaohua CHEN Shengbo ZHU Bingxue 《Chinese Geographical Science》 SCIE CSCD 2018年第6期946-956,共11页
The dynamics of snow cover differs greatly from basin to basin in the Songhua River of Northeast China, which is attributable to the differences in the topographic shift as well as changes in the vegetation and climat... The dynamics of snow cover differs greatly from basin to basin in the Songhua River of Northeast China, which is attributable to the differences in the topographic shift as well as changes in the vegetation and climate since the hydrological year(HY) 2003. Daily and flexible multi-day combinations from the HY 2003 to 2014 were produced using Moderate Resolution Imaging Spectroradiometer(MODIS) from Terra and Aqua remote sensing satellites for the snow cover products in the three basins including the Nenjiang River Basin(NJ), Downstream Songhua River Basin(SD) and Upstream Songhua River Basin(SU). Snow cover duration(SCD) was derived from flexible multiday combination each year. The results showed that SCD was significantly associated with elevation, and higher SCD values were found out in the mountainous areas. Further, the average SCDs of NJ, SU and SD basins were 69.43, 98.14 and 88.84 d with an annual growth of 1.36, 2.04 and 2.71 d, respectively. Binary decision tree was used to analyze the nonlinear relationships between SCD and six impact factors, which were successfully applied to simulate the spatial distribution of depth and water equivalent of snow. The impact factors included three topographic factors(elevation, aspect and slope), two climatic factors(precipitation and air temperature) and one vegetation index(Normalized Difference Vegetation Index, NDVI). By treating yearly SCD values as dependent variables and six climatic factors as independent variables, six binary decision trees were built through the combination classification and regression tree(CART) with and without the consideration of climate effect. The results from the model show that elevation, precipitation and air temperature are the three most influential factors, among which air temperature is the most important and ranks first in two of the three studied basins. It is suggested that SCD in the mountainous areas might be more sensitive to climate warming, since precipitation and air temperature are the major factors controlling the persistence of snow cover in the mountainous areas. 展开更多
关键词 binary decision tree MODIS snow cover duration topography climate changes
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A Novel Binary Firefly Algorithm for the Minimum Labeling Spanning Tree Problem 被引量:1
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作者 Mugang Lin Fangju Liu +1 位作者 Huihuang Zhao Jianzhen Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第10期197-214,共18页
Given a connected undirected graph G whose edges are labeled,the minimumlabeling spanning tree(MLST)problemis to find a spanning tree of G with the smallest number of different labels.TheMLST is anNP-hard combinatoria... Given a connected undirected graph G whose edges are labeled,the minimumlabeling spanning tree(MLST)problemis to find a spanning tree of G with the smallest number of different labels.TheMLST is anNP-hard combinatorial optimization problem,which is widely applied in communication networks,multimodal transportation networks,and data compression.Some approximation algorithms and heuristics algorithms have been proposed for the problem.Firefly algorithm is a new meta-heuristic algorithm.Because of its simplicity and easy implementation,it has been successfully applied in various fields.However,the basic firefly algorithm is not suitable for discrete problems.To this end,a novel discrete firefly algorithm for the MLST problem is proposed in this paper.A binary operation method to update firefly positions and a local feasible handling method are introduced,which correct unfeasible solutions,eliminate redundant labels,and make the algorithm more suitable for discrete problems.Computational results show that the algorithm has good performance.The algorithm can be extended to solve other discrete optimization problems. 展开更多
关键词 Minimum labeling spanning tree problem binary firefly algorithm META-HEURISTICS discrete optimization
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THE NEW METHOD OF GENERATION OF BINARY TREES FROM ZER0(0) AND ONE(1) CODES
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作者 蔡恒 《Journal of China Textile University(English Edition)》 EI CAS 1995年第2期94-99,共6页
A binary tree can be represented by a code reflecting the traversal of the corresponding regular binary tree in given monotonic order. A different coding scheme based on the branches of a regular binary tree with n-no... A binary tree can be represented by a code reflecting the traversal of the corresponding regular binary tree in given monotonic order. A different coding scheme based on the branches of a regular binary tree with n-nodes is proposed. It differs from the coding scheme generally used and makes no distinction between internal nodes and terminal nodes. A code of a regular binary tree with nnodes is formed by labeling the left branches by O’s and the right branches by l’s and then traversing these branches in pre-order. Root is always assumed to be on a left branch. 展开更多
关键词 code TRAVERSAL MONOTONIC order binary tree RECURSION backtrack approach algorithm design.
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Binary Tree’s Recursion Traversal Algorithm and Its Improvement
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作者 Hua Li 《Journal of Computer and Communications》 2016年第7期42-47,共6页
Binary tree is a very important data structure in computer science. Some major properties are discussed. Both recursive and non-recursive traversal methods of binary tree are discussed in detail. Some improvement... Binary tree is a very important data structure in computer science. Some major properties are discussed. Both recursive and non-recursive traversal methods of binary tree are discussed in detail. Some improvements in programming are proposed. 展开更多
关键词 binary tree TRAVERSAL STACK
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Recursive and Nonrecursive Traversal Algorithms for Dynamically Created Binary Trees
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作者 Robert Logozar 《Computer Technology and Application》 2012年第5期374-382,共9页
The modeling of dynamical systems from a time series implemented by our DSA program introduces binary trees of height D with all leaves on the same level, and the related subtrees of height L 〈 D. These are called e-... The modeling of dynamical systems from a time series implemented by our DSA program introduces binary trees of height D with all leaves on the same level, and the related subtrees of height L 〈 D. These are called e-trees and e-subtrees. The recursive and nonrecursive versions of the traversal algorithms for the trees with dynamically created nodes are discussed. The original nonrecursive algorithms that return the pointer to the next node in preorder, inorder and postorder traversals are presented. The space-time complexity analysis shows and the execution time measurements confirm that for these O(2D) algorithms, the recursive versions have approximately 10-25% better time constants. Still, the use of nonrecursive algorithms may be more appropriate in several occasions. 展开更多
关键词 binary e-trees algorithms tree traversal PREORDER inorder postorder RECURSIVE nonrecursive space-time complexity.
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Design and implementation of binary tree data structure based on DNA computing
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作者 YANG Chun-de WEI Guo-hui 《重庆邮电大学学报(自然科学版)》 北大核心 2009年第2期292-295,共4页
The designing,encodings and an instance of simulation of a binary tree for DNA computer were proposed,which utilizes the method of biology to complete inserting and deleting of the binary tree. Firstly,DNA encodings f... The designing,encodings and an instance of simulation of a binary tree for DNA computer were proposed,which utilizes the method of biology to complete inserting and deleting of the binary tree. Firstly,DNA encodings for storage and all elements of the binary tree were completely given out. Then, the implementations of all bio-operations in DNA computer were described. Finally, to prove the feasibility of this method, an actual binary tree with detailed nucleotide encodings was introduced. The process of an algorithm implemented on this binary tree was demonstrated. Based on this method, more other data structures in DNA computer can be developed. 展开更多
关键词 DNA计算机 完全二叉树 数据结构 设计 生物学方法 基因编码 核苷酸 证明
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Efficient Binary Tree Multiclass SVM Using Genetic Algorithms for Vowels Recognition
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作者 Boutkhil Sidaoui Kaddour Sadouni 《通讯和计算机(中英文版)》 2012年第10期1116-1123,共8页
关键词 元音识别 遗传算法 SVM 二叉树 支持向量机 多类分类 测试阶段 训练时间
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基于动态时间型二叉树的隐蔽通信模型
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作者 佘维 马佳伟 +3 位作者 张淑慧 程孔 刘炜 田钊 《通信学报》 北大核心 2025年第2期147-165,共19页
针对区块链隐蔽通信效率与安全问题,提出一种基于动态时间型二叉树的隐蔽通信模型。通过特定时刻动态生成时间型二叉树,利用根哈希提取随机因子为树节点分配不同的路径编码,将通信信息字符映射为编码路径及索引字段。通过将特定时刻嵌... 针对区块链隐蔽通信效率与安全问题,提出一种基于动态时间型二叉树的隐蔽通信模型。通过特定时刻动态生成时间型二叉树,利用根哈希提取随机因子为树节点分配不同的路径编码,将通信信息字符映射为编码路径及索引字段。通过将特定时刻嵌入路径编码空置位并整合至区块链交易实现隐蔽传输,接收端通过解析特定时刻重构时间型二叉树完成解码。实验结果表明,相较于同类模型,所提模型在保证安全性的同时提升了通信效率,并避免了预协商过程带来的安全隐患。 展开更多
关键词 区块链 动态时间型二叉树 路径编码 隐蔽通信
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磁流变液制动器系统区间动态可靠性分析
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作者 杨恒 张宇鹏 +3 位作者 杨鹏凯 李淑君 董青 王震 《哈尔滨工程大学学报》 北大核心 2025年第2期301-308,319,共9页
针对磁流变液制动器结构冗余、失效数据少且动态失效等问题,本文引入动态故障树和区间理论,提出一种区间动态故障树的磁流变液制动器系统可靠性分析方法。融合区间理论和动态故障树,提出区间动态故障树方法,并推导了区间动态故障门和区... 针对磁流变液制动器结构冗余、失效数据少且动态失效等问题,本文引入动态故障树和区间理论,提出一种区间动态故障树的磁流变液制动器系统可靠性分析方法。融合区间理论和动态故障树,提出区间动态故障树方法,并推导了区间动态故障门和区间动态故障树重要度求解方法;分析和定义了磁流变液制动器的故障模式影响及危害性和严酷度等级,同时,建立了磁流变液制动器的系统动态故障树;以某新型多槽式磁流变液制动器为例开展了可靠性和重要度分析,验证了方法的可行性和与产品失效的一致性。研究为磁流变液制动器的推广应用和优化和改进优化提供了理论依据。 展开更多
关键词 磁流变液制动器 区间理论 动态故障树 MARKOV链 二元决策图(BDD) 模块化分解 系统可靠性 重要度
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BTreeU-Topk:基于二叉树的不确定数据上的Top-k查询算法 被引量:2
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作者 张慧 郑吉平 韩秋廷 《计算机研究与发展》 EI CSCD 北大核心 2012年第10期2095-2105,共11页
应用需求的发展衍生各种查询类型,Top-k查询是交互环境下一种重要查询类型.由于数据的不确定性,传统数据上的Top-k查询技术和方法不能直接应用于不确定数据查询.在已有不确定数据上Top-k查询算法的基础上,提出基于二叉树的不确定数据上T... 应用需求的发展衍生各种查询类型,Top-k查询是交互环境下一种重要查询类型.由于数据的不确定性,传统数据上的Top-k查询技术和方法不能直接应用于不确定数据查询.在已有不确定数据上Top-k查询算法的基础上,提出基于二叉树的不确定数据上Top-k查询算法BTreeU-Topk;为了提高算法执行效率,对二叉树进行修剪操作进而提出BTreeOPTU-Topk和BTreePU-Topk算法.实验结果表明,BTreeU-Topk,BTreeOPTU-Topk以及BTreePU-Topk算法在不同数据分布以及k值增长时均优于现有算法. 展开更多
关键词 不确定数据 可能世界语义 二叉树 Top—k BtreeU—Topk U—Topk
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应用于PLC开发的梯形图向语句表转换的新方法
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作者 魏晓晴 郝方 +2 位作者 姜涛 康冰冰 赵念 《现代电子技术》 北大核心 2025年第1期168-172,共5页
为了设计一种PLC控制器,文中重点研究了PLC编程系统中由梯形图到语句表编译解算的实现过程,并提出一种应用于PLC开发的梯形图转换为语句表的新方法,即基于节点势能的转换方法。该方法将梯形图类比电路图,仿照电势能,以节点势能表示虚拟... 为了设计一种PLC控制器,文中重点研究了PLC编程系统中由梯形图到语句表编译解算的实现过程,并提出一种应用于PLC开发的梯形图转换为语句表的新方法,即基于节点势能的转换方法。该方法将梯形图类比电路图,仿照电势能,以节点势能表示虚拟梯形图中的能量流动,通过对梯形图节点势能的确定,将梯形图各图元之间的连接关系抽象为数值关系,并以此关系建立二叉树,遍历生成语句表。该方法简单清晰,以一种复杂度较低的数据结构将梯形图完整地描述出来,能够准确快速地完成由梯形图到语句表的编译解算,并可适用于逻辑关系比较复杂的梯形图程序的转换。该转换方法也能够为其他类似图形关系的解算提供参考,具有普遍适用性。 展开更多
关键词 PLC 梯形图 语句表 转换方法 节点势能 二叉树
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二叉Trie树下电力监控分布式数据库安全访问混沌加密控制
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作者 巩宇 胡文兴 +2 位作者 于亚雄 崔钰 刘轩 《沈阳工业大学学报》 北大核心 2025年第1期83-91,共9页
【目的】电力监控系统承载着大量敏感信息,包括电力设备的运行数据、电力负荷情况及用户用电信息等。这些数据对保障电力系统的安全和稳定至关重要,因此保证这些数据的安全性是电力监控系统的关键。分布式数据库作为电力监控系统的核心... 【目的】电力监控系统承载着大量敏感信息,包括电力设备的运行数据、电力负荷情况及用户用电信息等。这些数据对保障电力系统的安全和稳定至关重要,因此保证这些数据的安全性是电力监控系统的关键。分布式数据库作为电力监控系统的核心组成部分,具有处理速度快、数据存储量大等优势,但也面临着数据泄露、非法访问等安全隐患。【方法】为了增强电力监控系统的安全性,提出了一种基于二叉Trie树的电力监控分布式数据库安全访问混沌加密控制方法。采用SRP-6协议进行身份认证,确保只有经过授权的用户能够访问电力监控系统。SRP-6协议通过对身份信息的加密处理,有效防止了恶意攻击者伪造身份访问。在分布式数据库的环境中,密钥的管理是极具挑战性的任务。由于分布式系统涉及多个节点,且不同用户的权限和密钥各不相同,因此需要建立一个高效且安全的密钥管理机制。本文采用了二叉Trie树作为密钥管理结构,二叉Trie树是一种能够快速检索和存储密钥的高效数据结构,通过二叉Trie树的层次化结构,实现密钥的快速定位和分配。每个节点代表密钥管理中的一个步骤,叶节点则存储具体的加密密钥。通过这种树形结构,系统可以轻松管理大量的密钥,减少了密钥存储的冗余,同时提高了密钥分发的效率。二叉Trie树的使用也降低了密钥泄露的风险,增强了系统的整体安全性。在密钥管理的基础上,引入混沌加密技术,结合Tent映射和Logistic映射两种混沌模型,用于生成加密数据所需的随机数和轮密钥。Tent映射通过折叠和扩展操作将输入值映射到[0,1)区间,而Logistic映射则通过迭代生成伪随机序列,两者共同构成了混沌加密的基础。通过这种方式,电力监控分布式数据库中的数据被加密为不可预测的密文,极大程度上提高了攻击者通过分析密文推导明文的难度。【结果】所提方法在增强加密强度和提高系统安全性的同时,还具备较好的性能。通过控制密文分布的频率,保证加密数据的均匀性,密文的分布频次能够保持在2800次以上。雪崩效应值超过0.524,证明了所提方法在数据加密方面的有效性。【结论】与传统方法相比,本文方法在保证数据安全性的同时,减少了计算和存储资源的消耗,适合大规模分布式数据库的应用。 展开更多
关键词 二叉Trie树 电力监控 分布式数据库 安全访问 混沌加密 SRP-6协议 TENT映射 LOGISTIC映射
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基于云计算的电力能源数据多通道采集方法研究
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作者 王娅云 李增伟 +3 位作者 魏永瑜 张译 李生帛 王钰琳 《信息技术》 2025年第2期162-167,共6页
常规的电力能源数据采集方法,在数据的传输过程中存在一定的数据误差,导致采集的数据误差较大,因此,提出电力能源数据多通道采集方法。根据动态二进制树防碰撞算法,对数据交互过程设置,按照交互数据对电力数据标签预处理。建立云计算传... 常规的电力能源数据采集方法,在数据的传输过程中存在一定的数据误差,导致采集的数据误差较大,因此,提出电力能源数据多通道采集方法。根据动态二进制树防碰撞算法,对数据交互过程设置,按照交互数据对电力数据标签预处理。建立云计算传输感知模型,对预处理后的数据连接。采用多路复用的方式,构建稀疏矩阵,设置数据的采集间隔,采集数据索引规则以及数据的采集命令,从而对电力能源数据进行采集。实验结果表明,使用文中设计的方法对电力能源数据进行多通道采集,其采集误差处于0.1A以内,应用效果较好。 展开更多
关键词 云计算 电力能源 多通道数据采集 二进制树防碰撞算法 数据交互
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Reliability Analysis of Electrical System of CNC Machine Tool Based on Dynamic Fault Tree Analysis Method 被引量:2
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作者 晏晶 尹珩苏 +2 位作者 周杰 李彦锋 黄洪钟 《Journal of Donghua University(English Edition)》 EI CAS 2015年第6期1042-1046,共5页
The electrical system of CNC machine tool is very complex which involves many uncertain factors and dynamic stochastic characteristics when failure occurs.Therefore,the traditional system reliability analysis method,f... The electrical system of CNC machine tool is very complex which involves many uncertain factors and dynamic stochastic characteristics when failure occurs.Therefore,the traditional system reliability analysis method,fault tree analysis(FTA)method,based on static logic and static failure mechanism is no longer applicable for dynamic systems reliability analysis.Dynamic fault tree(DFT)analysis method can solve this problem effectively.In this method,DFT first should be pretreated to get a simplified fault tree(FT);then the FT was modularized to get the independent static subtrees and dynamic subtrees.Binary decision diagram(BDD)analysis method was used to analyze static subtrees,while an approximation algorithm was used to deal with dynamic subtrees.When the scale of each subtree is smaller than the system scale,the analysis efficiency can be improved significantly.At last,the usefulness of this DFT analysis method was proved by applying it to analyzing the reliability of electrical system. 展开更多
关键词 RELIABILITY dynamic fault tree MODULARIZATION binary decision diagram approximation algorithm CNC machine tool
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Blocking optimized SIMD tree search on modern processors 被引量:2
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作者 张倬 陆宇凡 +2 位作者 沈文枫 徐炜民 郑衍衡 《Journal of Shanghai University(English Edition)》 CAS 2011年第5期437-444,共8页
Tree search is a widely used fundamental algorithm. Modern processors provide tremendous computing power by integrating multiple cores, each with a vector processing unit. This paper reviews some studies on exploiting... Tree search is a widely used fundamental algorithm. Modern processors provide tremendous computing power by integrating multiple cores, each with a vector processing unit. This paper reviews some studies on exploiting single instruction multiple date (SIMD) capacity of processors to improve the performance of tree search, and proposes several improvement methods on reported SIMD tree search algorithms. Based on blocking tree structure, blocking for memory alignment and dynamic blocking prefetch are proposed to optimize the overhead of memory access. Furthermore, as a way of non-linear loop unrolling, the search branch unwinding shows that the number of branches can exceed the data width of SIMD instructions in the SIMD search algorithm. The experiments suggest that blocking optimized SIMD tree search algorithm can achieve 1.6 times response speed faster than the un-optimized algorithm. 展开更多
关键词 single instruction multiple date (SIMD) tree search binary search streaming SIMD extensions (SSE) Cell broadband engine (BE)
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<i>T</i><sub>3</sub>Tree and Its Traits in Understanding Integers 被引量:1
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作者 Xingbo Wang 《Advances in Pure Mathematics》 2018年第5期494-507,共14页
Valuated binary tree is emerging its magical characteristics in study of integers. As the father tree of all valuated binary subtrees, T3 tree plays a very important role in studying the odd integers for its owning bo... Valuated binary tree is emerging its magical characteristics in study of integers. As the father tree of all valuated binary subtrees, T3 tree plays a very important role in studying the odd integers for its owning both the common properties of a general valuated binary tree and its own traits of covering all the odd integers bigger than 1. The article investigates the properties of the T3 tree as well as the multiplications on the tree. It exhibits the distribution of a node's multiples, the distribution of the product of two nodes and the distribution of the square of a node. Some other contents such as fundamental properties of the T3 tree and path connecting a product to its divisor-nodes are also investigated with detail mathematical proofs. The theorems and corollaries proved in the article lay a foundation for future work. 展开更多
关键词 Number Theory Valuated binary tree MULTIPLICATION
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二叉树CreateBTree算法的改进 被引量:2
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作者 凌国贤 《广西科学院学报》 2003年第2期69-71,76,共4页
在分析二叉树的 Create BTree算法的基础上 ,利用线性探测再散列方法对 Create B-Tree算法的中序遍历序列进行预处理来改进 Create BTree算法 ,使得改进后的 Create BTree算法在最差情况下 ,时间复杂度由 O(N 2 )降为 O(N )。
关键词 二叉树 CreateBtree算法 线性探测再散列方法 中序遍历序列 时间复杂度
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Prefix Subsection Matching Binary Algorithm in Passive RFID System
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作者 王新锋 俞静一 +1 位作者 张绍军 周颖 《Defence Technology(防务技术)》 SCIE EI CAS 2011年第2期82-86,共5页
Identifying speed,tag average response times and reliability are the most important capabilities in passive RFID(radio frequency identification) system.QT(query tree) is a famous algorithm for lowest-cost RFID tags,bu... Identifying speed,tag average response times and reliability are the most important capabilities in passive RFID(radio frequency identification) system.QT(query tree) is a famous algorithm for lowest-cost RFID tags,but its shortcoming is high searching delay and high tag average response times.A prefix subsection matching binary(PSMB) algorithm based on QTalgorithm is proposed.The key idea of PSMB anti-collision algorithm is that,during searching phase,a given reader uses the particular tags ID,which has been searched out formerly,to shorten searching delay and depress tag average response times.The idea of PSMB algorithm can be described as follows.Usually,tag ID is composed of several subsections which have different meanings.Based on the tags ID searched out formerly,a given reader builds a prefix database.In subsequent searching phase,the reader uses its prefix database to deduce searching space of tag ID.Simulation results show that identification delay of PSMB algorithm is about 1/3 of QTalgorithm,tag average response times is about 1/4 of QTalgorithm,and system throughput rate is treble QTalgorithm. 展开更多
关键词 information processing radio frequency identification ANTI-COLLISION binary tree prefix matching
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