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SCORE SETS IN ORIENTED 3-PARTITE GRAPHS
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作者 S.Pirzada Merajuddin T.A.Naikoo 《Analysis in Theory and Applications》 2007年第4期363-374,共12页
Abstract. Let D (U, V, W) be an oriented 3-partite graph with | U | = p, |V| = q and |W | = r. For any vertex x in D(U,V,W), let dx^+ and dui^- be the outdegree and indegree ofx respectively. Define aui (o... Abstract. Let D (U, V, W) be an oriented 3-partite graph with | U | = p, |V| = q and |W | = r. For any vertex x in D(U,V,W), let dx^+ and dui^- be the outdegree and indegree ofx respectively. Define aui (or simply ai) = q + r + dui^+ - dui^-, bvj (or simply b j) = p + r + d^+vj - d^-vj and cwk (or simply ck) =p + q + dwk^+ -dwk^- as the scores of ui in U,vj in V and wk in W respectively. The set A of distinct scores of the vertices of D(U, V, W) is called its score set. In this paper, we prove that if a1 is a non-negative integer, ai(2 ≤ i ≤ n - 1) are even positive integers and an is any positive integer, then for n 〉 3, there exists an oriented 3-partite graph with the score set A ={a1,Σ2i=1 ai,…,Σni=1 ai}, except when A = {0, 2, 3}. Some more results for score sets in oriented 3-partite graphs are obtained. 展开更多
关键词 oriented graph oriented 3-partite graph tournament score set
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Complexity of Injective Homomorphisms to Small Tournaments, and of Injective Oriented Colourings
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作者 Russell J. Campbell Nancy E. Clarke Gary MacGillivray 《Open Journal of Discrete Mathematics》 2023年第1期1-15,共15页
Several possible definitions of local injectivity for a homomorphism of an oriented graph G to an oriented graph H are considered. In each case, we determine the complexity of deciding whether there exists such a homo... Several possible definitions of local injectivity for a homomorphism of an oriented graph G to an oriented graph H are considered. In each case, we determine the complexity of deciding whether there exists such a homomorphism when G is given and H is a fixed tournament on three or fewer vertices. Each possible definition leads to a locally-injective oriented colouring problem. A dichotomy theorem is proved in each case. 展开更多
关键词 Injective graph Homomorphism oriented Colouring COMPLEXITY
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A NOTE ON PANCYCLIC ORIENTED GRAPH
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作者 宋增民 陈黎明 《Journal of Southeast University(English Edition)》 EI CAS 1995年第2期77-82,共6页
Let D be a diagraph of order n≥9 and δ≥n-2. If for every pairof vertices u, v∈V(D) , either uv∈ A(D) or . Theauthor has proved D is pancyclic before. In this paper we suppose n≥6 in-stead of n≥9 in above condit... Let D be a diagraph of order n≥9 and δ≥n-2. If for every pairof vertices u, v∈V(D) , either uv∈ A(D) or . Theauthor has proved D is pancyclic before. In this paper we suppose n≥6 in-stead of n≥9 in above condition, and show the same result holds except 6s 展开更多
关键词 oriented graph PANCYCLICITY DEGREE
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System Dependence Graph Construction for Aspect Oriented C++
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作者 SHI Liang XU Baowen 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第3期555-560,共6页
This paper proposes an extended system dependence graph called AspectSDG to represent control and data dependences for AspeetC++ programs, and presents an approach for the construction of AspectSDG. This approach de... This paper proposes an extended system dependence graph called AspectSDG to represent control and data dependences for AspeetC++ programs, and presents an approach for the construction of AspectSDG. This approach decomposes aspect-oriented programs into three parts: component codes, aspect codes, and weaving codes. It constructs program dependence graphs (PDGs) for each part, and then connects the PDGs at call sites to form the complete AspectSDG. The AspectSDG can deal with advice precedence correctly, and represent the additional dependences caused by aspect codes. Based on this model, we introduce how to compute a static slice of an AspectC+ + program. 展开更多
关键词 program analysis system dependence graph ASPECT-oriented slicing
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On Imbalances in Oriented Tripartite Graphs
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作者 S. PIRZADA T. A. NAIKOO Nasir A. SHAH 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2011年第5期927-932,共6页
An oriented tripartite graph is the result of assigning a direction to each edge of a simple tripartite graph. For any vertex x in an oriented tripartite graph D(U, V, W), let dx^+ and dx^- denote the outdegree and... An oriented tripartite graph is the result of assigning a direction to each edge of a simple tripartite graph. For any vertex x in an oriented tripartite graph D(U, V, W), let dx^+ and dx^- denote the outdegree and indegree respectively of x. Define aui: dui^+ - dus^-, bvj = dvj^+ - dvj^- and cwk = dwk^+ - dwk^- as the imbalances of the vertices ui in U, vj in V and wk in W respectively. In this paper, we obtain criteria for sequences of integers to be the imbalances of some oriented tripartite graph. Keywords Digraph, imbalance, outdegree, indegree, oriented graph, oriented tripartite graph, arc 展开更多
关键词 Digraph imbalance outdegree indegree oriented graphs oriented tripartite graph arc
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Dynamic Slicing of Object Oriented Programs
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作者 Jian\|jun Zhao Department of Computer Science and Engineering, Fukuoka Institute of Technology, Fukuoka 811 0295, Japan 《Wuhan University Journal of Natural Sciences》 CAS 2001年第Z1期391-397,共7页
Program slice has many applications such as program debugging, testing, maintenance, and complexity measurement. A static slice consists of all statements in program P that may effect the value of variable v a... Program slice has many applications such as program debugging, testing, maintenance, and complexity measurement. A static slice consists of all statements in program P that may effect the value of variable v at some point p , and a dynamic slice consists only of statements that influence the value of variable occurrence for specific program inputs. In this paper, we concern the problem of dynamic slicing of object oriented programs which, to our knowledge, has not been addressed in the literatures. To solve this problem, we present the dynamic object oriented dependence graph (DODG)which is an arc classified digraph to explicitly represent various dynamic dependence between statement instances for a particular execution of an object oriented program. Based on the DODG, we present a two phase backward algorithm for computing a dynamic slice of an object oriented program. 展开更多
关键词 program slicing dynamic dependence graph object oriented program SOFTWARE maintenance DEBUGGING testing
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Length of the Longest Path and Diameter in Orientations of Graphs
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作者 Bing Zhou 《Open Journal of Discrete Mathematics》 2017年第2期65-70,共6页
We say that a parameter p of directed graphs has the interval property if for every graph G?and orientations of G, p can take every value between its minimum and maximum values. Let &lambda;be the length of the lo... We say that a parameter p of directed graphs has the interval property if for every graph G?and orientations of G, p can take every value between its minimum and maximum values. Let &lambda;be the length of the longest directed path. A question asked by C. Lin in [1] is equivalent to the question of whether &lambda;has the interval property. In this note, we answer this question in the affirmative. We also show that the diameter of directed graphs does not have the interval property. 展开更多
关键词 Directed graphs graph Orientation INTERVAL Property Longest PATH PATH LENGTH DIAMETER
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Characterization and Construction of Permutation Graphs
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作者 Severino V. Gervacio Teofina A. Rapanut Phoebe Chloe F. Ramos 《Open Journal of Discrete Mathematics》 2013年第1期33-38,共6页
If is a permutation of , the graph has vertices where xy is an edge of if and only if (x, y) or (y, x) is an inversion of . Any graph isomorphic to is called a permutation graph. In 1967 Gallai characterized permutati... If is a permutation of , the graph has vertices where xy is an edge of if and only if (x, y) or (y, x) is an inversion of . Any graph isomorphic to is called a permutation graph. In 1967 Gallai characterized permutation graphs in terms of forbidden induced subgraphs. In 1971 Pnueli, Lempel, and Even showed that a graph is a permutation graph if and only if both the graph and its complement have transitive orientations. In 2010 Limouzy characterized permutation graphs in terms of forbidden Seidel minors. In this paper, we characterize permutation graphs in terms of a cohesive order of its vertices. We show that only the caterpillars are permutation graphs among the trees. A simple method of constructing permutation graphs is also presented here. 展开更多
关键词 PERMUTATION Inversion PERMUTATION graph COHESIVE Order oriented graph TOURNAMENT SCORE Sequence CATERPILLAR graph Composition
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Evolution of Word-updating Dynamical Systems (WDS) on Directed Graphs
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作者 郑洁 《Journal of Donghua University(English Edition)》 EI CAS 2009年第2期132-134,共3页
This paper continues the research on theoretical foundations for computer simulation.We introduce the concept of word-updating dynamical systems(WDS)on directed graphs,which is a kind of generalization of sequential d... This paper continues the research on theoretical foundations for computer simulation.We introduce the concept of word-updating dynamical systems(WDS)on directed graphs,which is a kind of generalization of sequential dynamical systems(SDS)on graphs.Some properties on WDS,especially some results on NOR-WDS,which are different from that on NOR-SDS,are obtained. 展开更多
关键词 word-updating dynamical system WDS functional directed graph acyclic orientation
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The Minimum Cut Sets of System Fault Based on Oriented Matrix Analysis
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作者 LIU An qing, LIU Yu hai Ordnance Engineering College, Shijiazhuang 050003, P.R.China 《International Journal of Plant Engineering and Management》 2001年第4期193-197,共5页
In this paper, the oriented matrix analysis (OMA) method of system reliability has been discussed. OMA uses a oriented fault graph instead of a traditional fault tree model. By defining the specific logic operation an... In this paper, the oriented matrix analysis (OMA) method of system reliability has been discussed. OMA uses a oriented fault graph instead of a traditional fault tree model. By defining the specific logic operation and calculating a reachability matrix, the cut sets can be formed directly and the minimum cut sets can be easily obtained. 展开更多
关键词 FAULT oriented graph REACHABILITY
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基于可视化知识图谱我国龙舟项目研究热点和导向分析
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作者 陈翀 吕艳丽 王昊 《吉林体育学院学报》 2024年第3期7-15,共9页
研究基于可视化分析探索我国龙舟项目的研究热点与导向,为我国龙舟项目的健康发展提供有价值的参考。运用可视化知识图谱文献计量法,以问题为导向梳理我国龙舟项目科研成果,分析现状、研究热点和导向,从而提出合理的发展路径。研究认为... 研究基于可视化分析探索我国龙舟项目的研究热点与导向,为我国龙舟项目的健康发展提供有价值的参考。运用可视化知识图谱文献计量法,以问题为导向梳理我国龙舟项目科研成果,分析现状、研究热点和导向,从而提出合理的发展路径。研究认为,我国关于龙舟研究成果较多,主要论点围绕龙舟赛事、传统体育、体育文化、体育史、发展和民俗(端午节)6个方面展开,其内容涵盖了龙舟活动、龙舟文化、历史演绎和发展各个方面,形成了龙舟赛事活动和传播、龙舟传统体育文化演绎和发展、龙舟发展问题分析和龙舟项目国际化对比和发展4个研究导向。龙舟文化传承和发展贯穿龙舟运动始终,也是我国龙舟项目健康持续发展的法宝。 展开更多
关键词 可视化知识图谱 龙舟项目 热点导向
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面向方面级情感分析的交互式关系图注意力网络
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作者 郭磊 贾真 李天瑞 《计算机应用》 CSCD 北大核心 2024年第3期696-701,共6页
方面级情感分析领域主要采用基于注意力机制的神经网络模型,这类模型忽略了方面词与观点词之间的依存关系和方面词与上下文词之间的距离,导致该类模型情感分类结果不够精确。为了解决上述问题,建立一种交互式关系图注意力网络(RI-GAT)... 方面级情感分析领域主要采用基于注意力机制的神经网络模型,这类模型忽略了方面词与观点词之间的依存关系和方面词与上下文词之间的距离,导致该类模型情感分类结果不够精确。为了解决上述问题,建立一种交互式关系图注意力网络(RI-GAT)模型。首先,通过长短期记忆(LSTM)网络学习句子的语义特征;然后,将学习的语义特征结合句子的位置信息生成新的特征;最后,在新的特征中提取各方面词和观点词之间的依存关系,实现对句法依存信息和位置信息的高效利用。在Laptop、Restaurant和Twitter数据集上的实验结果表明,相较于次优的动态多通道图卷积网络(DM-GCN),RI-GAT模型分类准确率(Acc)提高了0.67、1.65和1.36个百分点,说明了RI-GAT模型可以更好地建立方面词和意见词之间的联系,使得情感分类更加精确。 展开更多
关键词 方面级情感分析 图注意力网络 语义特征 观点倾向 网络评论
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基于Visual Graph的电力图形系统开发 被引量:23
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作者 林济铿 覃岭 罗萍萍 《电力系统自动化》 EI CSCD 北大核心 2005年第15期73-76,共4页
针对传统面对对象的图形系统开发周期长、维护困难的缺点,基于通用图形开发平台——VisualGraph,提出了一种简便、清晰的面向图形对象的建模新方法。用可视化图形类建立电力元件并组成电网结构图,快速开发出图形系统。建模及过程全部实... 针对传统面对对象的图形系统开发周期长、维护困难的缺点,基于通用图形开发平台——VisualGraph,提出了一种简便、清晰的面向图形对象的建模新方法。用可视化图形类建立电力元件并组成电网结构图,快速开发出图形系统。建模及过程全部实现可视化,十分快捷。实际应用表明,该方法是有效的,所开发的图形系统具有良好的实际应用前景。 展开更多
关键词 VISUAL graph 面向图形对象 电网结构图 图形系统
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面向领域的网页文本校对方法
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作者 田莎 刘晓强 李柏岩 《计算机与数字工程》 2024年第6期1788-1794,共7页
随着网络技术的快速发展,网站越来越成为各个机构发布和管理信息必不可少的渠道,用户也习惯使用浏览网页的方式去获取信息。随着公开信息量急剧增长,文本编辑和校对过程中难免会存在一些错误,自动文本校对是一个必要的辅助手段。目前针... 随着网络技术的快速发展,网站越来越成为各个机构发布和管理信息必不可少的渠道,用户也习惯使用浏览网页的方式去获取信息。随着公开信息量急剧增长,文本编辑和校对过程中难免会存在一些错误,自动文本校对是一个必要的辅助手段。目前针对文本编辑错误的研究较多,已有一些工具可以支持,但知识表述错误涉及具体的领域知识和语义关系,普通校对工具无法胜任。论文重点针对知识表述错误类的文本校对进行研究,提出一种基于知识图谱的面向领域知识的文本校对方法,论述了领域知识图谱的构建方法与流程、待校对文本的知识抽取方法以及基于知识图谱的校对方法。实验结果显示,该方法能够检测出网页中的语义错误,弥补通用检测工具的不足。 展开更多
关键词 面向领域 文本校对 知识图谱 关键词提取 知识表述
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知识图谱赋能的面向对象程序设计C++教学改革与实践
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作者 裴壮 田秀霞 李冰雪 《华东师范大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第5期104-113,共10页
在国家新工科建设背景下,早期的C++教学已不能满足“两性一度”(高阶性、创新性和挑战度)的要求,另外存在知识点碎片化、理论与实践难以结合、单视角偏差等问题,针对以上问题,通过将QT(Qt Toolkit)和C++这两门课程合二为一,提出了有效融... 在国家新工科建设背景下,早期的C++教学已不能满足“两性一度”(高阶性、创新性和挑战度)的要求,另外存在知识点碎片化、理论与实践难以结合、单视角偏差等问题,针对以上问题,通过将QT(Qt Toolkit)和C++这两门课程合二为一,提出了有效融合QT和C++的创新教学模式,并在智慧树平台部署了相应的课程知识图谱辅助教学.一方面,扩展了教学的广度,有效关联课程知识点,实现多模态教学资源的整合和共享,促进学生多视角学习知识,体现课程的创新性和避免单视角偏差;另一方面,提高了教学的深度,构造融合QT和面向对象程序设计C++的知识图谱,通过这两门课程知识点的有机融合,搭建从理论到实践的桥梁,提高课程高阶性和挑战度.本研究另辟蹊径,为C++的教学改革开辟了新途径,也为其他高校的编程课程教学改革提供了有价值的参考和借鉴. 展开更多
关键词 面向对象程序设计C++ QT(Qt Toolkit) 知识图谱 智慧教育
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Application of Contact Graph Routing in Satellite Delay Tolerant Networks 被引量:5
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作者 ZHU Laitao LI Yong +3 位作者 ZHANG Junxiang WU Jing TAI Xiao ZHOU Jianguo 《空间科学学报》 CAS CSCD 北大核心 2015年第1期116-125,共10页
Satellite networks have many inherent advantages over terrestrial networks and have become an important part of the global network infrastructure.Routing aimed at satellite networks has become a hot and challenging re... Satellite networks have many inherent advantages over terrestrial networks and have become an important part of the global network infrastructure.Routing aimed at satellite networks has become a hot and challenging research topic.Satellite networks,which are special kind of Delay Tolerant Networks(DTN),can also adopt the routing solutions of DTN.Among the many routing proposals,Contact Graph Routing(CGR) is an excellent candidate,since it is designed particularly for use in highly deterministic space networks.The applicability of CGR in satellite networks is evaluated by utilizing the space oriented DTN gateway model based on OPNET(Optimized Network Engineering Tool).Link failures are solved with neighbor discovery mechanism and route recomputation.Earth observation scenario is used in the simulations to investigate CGR's performance.The results show that the CGR performances are better in terms of effectively utilizing satellite networks resources to calculate continuous route path and alternative route can be successfully calculated under link failures by utilizing fault tolerance scheme. 展开更多
关键词 SATELLITE Delay TOLERANT Networks(DTN) Space oriented DTN GATEWAY CONTACT graph Routing(CGR) Link FAILURES
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Multi-scale Graph-matching Based Kernel for Character Recognition from Natural Scenes 被引量:2
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作者 Cun-Zhao SHI Chun-Heng WANG +2 位作者 Bai-Hua XIAO Yang ZHANG Song GAO 《自动化学报》 EI CSCD 北大核心 2014年第4期751-756,共6页
认出从自然景色图象提取的字符由于 intraclass 变化的高度是相当挑战性的。在这份报纸,我们为景色特性识别建议一个多尺度的匹配图的基于的核。以便捕获人物的内在地特殊的结构,每幅图象被与多尺度的图象格子联系的几张图代表。当也... 认出从自然景色图象提取的字符由于 intraclass 变化的高度是相当挑战性的。在这份报纸,我们为景色特性识别建议一个多尺度的匹配图的基于的核。以便捕获人物的内在地特殊的结构,每幅图象被与多尺度的图象格子联系的几张图代表。当也越过邻近的节点保存空间一致性时,二幅图象的类似被匹配二张图(图象) 因此定义为最佳精力,它在图为每个节点发现最好的火柴。计算类似是合适的为支持向量机器(SVM ) 构造一个核。与多尺度的格子匹配图获得的多重核被联合以便最后的核是更柔韧的。挑战性的 Chars74k 和 ICDAR03-CH 数据集上的试验性的结果证明建议方法比现状方法更好表现。 展开更多
关键词 字符识别 自然场景 多尺度 内核 配基 场景图 图形表示 最佳匹配
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遥感智能信息处理的发展及技术前景 被引量:2
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作者 杨晓梅 王志华 +3 位作者 刘岳明 张俊瑶 刘晓亮 刘彬 《同济大学学报(自然科学版)》 EI CAS CSCD 北大核心 2023年第7期1025-1032,共8页
遥感信息提取技术虽不断推陈出新,但在智能化、精准实用性方面始终存在巨大的瓶颈问题,有必要围绕遥感智能计算和信息提取这个发展主题进行总结和讨论。从“机理—尺度—数据—智能”4个层面,逐步就遥感信息提取与定量反演路径的发展融... 遥感信息提取技术虽不断推陈出新,但在智能化、精准实用性方面始终存在巨大的瓶颈问题,有必要围绕遥感智能计算和信息提取这个发展主题进行总结和讨论。从“机理—尺度—数据—智能”4个层面,逐步就遥感信息提取与定量反演路径的发展融合、基于像素和面向对象不同处理单元模式、时空谱数据融合、遥感解译的智能化因素四方面进行剖析,从而提出未来“数据获取知识”和“知识引导数据”双向驱动、遥感大数据和地学知识图谱相融合的遥感智能计算架构,尝试推动遥感科学从经典向现代化的跃迁。 展开更多
关键词 遥感智能计算 信息提取 智能解译 面向对象 深度学习 时空融合 遥感大数据 地学知识图谱
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Reusable Function Discovery by Call-Graph Analysis
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作者 Dan Zhao Li Miao Dafang Zhang 《Journal of Software Engineering and Applications》 2015年第4期184-191,共8页
Nowadays, one of the IT challenges faced by many enterprises is the maintenance of their legacy system and migration of those systems to modern and flexible platform. In this paper, we study the network properties of ... Nowadays, one of the IT challenges faced by many enterprises is the maintenance of their legacy system and migration of those systems to modern and flexible platform. In this paper, we study the network properties of software call graphs, and utilize the network theories to understand the business logic of legacy system. The call graphs turn out approximately scale-free and small world network properties. This finding provides new insight to understand the business logic of legacy system: the methods in a program can be naturedly partitioned into the business methods group and supportive methods group. Moreover, the result is also very helpful in reusing valuable functionality and identifying what services should be to expose in the migration from legacy to modern SOA context. 展开更多
关键词 CALL graph Network Properties LEGACY System SERVICE-oriented architecture
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基于相机朝向变化的增量式位姿图分段算法
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作者 范涵奇 王劭靖 《计算机科学》 CSCD 北大核心 2023年第7期152-159,共8页
位姿图优化是估计相机轨迹过程中减少累积误差的重要方法,但随着相机的不断运动,位姿图的规模会不断增大导致优化速度下降,使得轨迹估计难以应用于AR/VR(Augmented Reality/Virtual Reality)等实时性要求较高的领域。针对此问题,文中提... 位姿图优化是估计相机轨迹过程中减少累积误差的重要方法,但随着相机的不断运动,位姿图的规模会不断增大导致优化速度下降,使得轨迹估计难以应用于AR/VR(Augmented Reality/Virtual Reality)等实时性要求较高的领域。针对此问题,文中提出了一种基于相机朝向变化的增量式位姿图分段算法。所提算法能够将位姿图在相机发生朝向变化较大的时刻进行分段,从而只对这些朝向变化较大的相机进行位姿图优化,以有效减小位姿图优化的规模,提高优化速度。针对其余未进行位姿图优化的每个相机,分别将其所在轨迹段的起始相机和终止相机作为参考相机,将根据不同参考相机估计出的不同位姿进行加权平均,从而求解出相机的最终位姿,既避免了非线性优化的大量计算,又降低了噪声的影响,达到了较高的精度。在EuRoC,TUM和KITTI数据集上进行了实验,结果表明,所提算法在减小位姿图优化规模的基础上保证了相机轨迹的精度。 展开更多
关键词 位姿图 相机朝向 轨迹分段 加权平均 增量式
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