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基于混合动态贝叶斯网络的无人机路径重规划

系统仿真学报 2006年第5期18卷 1301-1306页

作者：肖秦琨高晓光高嵩西北工业大学电子信息学院西安工业大学电子信息学院

针对无人机航迹规划的实时重规划能力,研究了局部路径构图的基本原则并提出了一种突发威胁体下无人机局部路径重规划的算法。首先根据不同威胁体的分布情况构造无人机的可飞航路集,用“改进型Voronoi图”表示出来,采用Dijkstra算法求解... 详细信息

针对无人机航迹规划的实时重规划能力,研究了局部路径构图的基本原则并提出了一种突发威胁体下无人机局部路径重规划的算法。首先根据不同威胁体的分布情况构造无人机的可飞航路集,用“改进型Voronoi图”表示出来,采用Dijkstra算法求解初始粗略最短路径。在无人机飞行过程中,通过基于混合动态贝叶斯网络的切换线性动态系统模型感知环境,应用Viterbi应用解码算法确定突发威胁体的实时位置及威胁等级,后依据局部路径重规划原则进行寻优,最后应用三次平滑及序列二次规划方法获得实际可飞路径。用Matlab仿真验证,证明了算法有效性。

关键词：无人战斗机局部路径重规划改进型Voronoi图混合动态贝叶斯网络切换线性系统

Ubiquitous indoor vision navigation using a smart device

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Geo-Spatial Information Science 2013年第3期16卷 177-185页

作者： Bei HUANG Yang gao Department of Geomatics Engineering University of Calgary2500 University Dr.NWCalgaryAlberta T2N 1N4Canada

GPS-based technology has served the positioning and navigation industry for decades with outstanding reliability and ***,limitations for location-based services in indoor scenarios remain where GPS signal reception suffers from severe degradation or even ***-Fi-based positioning is currently the most popular indoor location solution,with an availability and time-to-first-fix that are significantly better than ***,the achievable position accuracy is only at the level of tens of meters on average depending on database density and signal reception *** order to improve positioning accuracy and availability,motion sensors like accelerometers,gyros,and magnetic compasses are increasingly integrated into smart ***,their position solutions suffer from the effects of significant accumulative *** this paper,a vision-based indoor positioning method is developed to overcome the limitations *** proposed vision-based system relies on a single camera,widely available on smart phones and *** derivation of the absolute 3D position from 2D snapshots of a single camera requires the use of an external geo-reference *** this research,a ubiquitous floor plan database has been used to provide accurate geodetic *** other popular geo-reference databases,the database used in this work can easily be generated with existing *** proposed system has been developed as an iOS App and was tested on iPad for various indoor *** results show that the performance of the proposed system is superior to Wi-Fi-based positioning systems.

关键词： indoor positioning vision navigation geo-reference augmented reality

THE FULLY PLASTIC J-INTEGRAL OF CORNER CRACKS AT A HOLE IN A PLATE

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Acta Mechanica Solida Sinica 1997年第2期10卷 131-137页

作者： gao, Q Huang, ZZ SW JIATONG UNIV INST APPL MECHCHENGDU 610031PEOPLES R CHINA

The line-spring model of surface cracks is applied to the fully plastic analysis of corner cracks at a hole in a plate. The generalized fully plastic constitutive relations and the fully plastic J-integral, as well as its coefficients in polynomial expressions are given. The model obtained is incorporated into a finite element program. The corner cracks at a hole in a plate subjected pure tensions are calculated by the present model. The fully plastic J-integral is then estimated. The results obtained show that the line-spring model is effective for the analysis of corner cracks. The influence of the crack depth and the hardening exponent on the fully plastic J-integral is also discussed.

关键词： corner crack line-spring model fully plastic J-integral

Green Synthesis of CdSe Quantum Dots with Tunable Photoluminescent Properties

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Journal of the Chinese Ceramic Society 2014年第1期1卷 53-58页

作者： gao Bing SHEN chao YUAN Shuanglong YANG Yunxia CHEN Guorong Key Laboratory for Ultrafine Materials of Ministry of Education School of Materials Science and EngineeringEast China University of Science and Technology

The CdSe quantum dots（QDs） were synthesized with water phase Se precursor and non-toxic glycerol as a solvent of Cd precursor. According to the analysis by X-ray diffraction（XRD）, the phases of the product are pure. The particle size of the monodispersive QDs product determined by high resolution transmission electron microscopy（HRTEM） is 3.2 nm4.5 nm. Furthermore, compared to the CdSe bulk material, the band gap of QDs exhibits a blue shift, indicating that the size of the QDs product is in nanoscale. In addition, the photoluminescent spectra of CdSe QDs show red shifts from 529 nm to 591 nm when the size of CdSe QDs increases, due to the quantum size effect. The quantum yield of CdSe QDs is calculated to be 50.53%, which is greater than that of the CdSe QDs synthesized by other water phase methods.

关键词： Cd Se quantum dots(QDs) green synthesis photoluminescent properties quantum size effect quantum yield(QY)

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知识资本理论视角下的企业管理创新

未来与发展 2007年第3期28卷 34-37页

作者：高超贵州财经学院贵州贵阳550004

知识资本作为企业的无形资产,是一种极高的生产力,它能为企业创造超额垄断利润,但企业知识资本的转移和增值具有较高的外部性,需要企业进行有效的管理。目前,企业在运用知识资本时面临诸如知识资本的利用效率低、知识资本的共享和评价... 详细信息

知识资本作为企业的无形资产,是一种极高的生产力,它能为企业创造超额垄断利润,但企业知识资本的转移和增值具有较高的外部性,需要企业进行有效的管理。目前,企业在运用知识资本时面临诸如知识资本的利用效率低、知识资本的共享和评价困难、知识系统的失效等一系列问题。运用知识解决的企业运作模式,采用知识管理的市场化策略、系统化策略、社会化策略,建立知识型的企业组织结构、文化诱导模式和企业知识资产的自身保护体系,调整企业财务管理的主要内容,企业就能适应社会的发展和环境的变化,提高知识资本的利用效率,实现在知识资本环境下的企业管理创新。

关键词：知识资本企业管理创新

Protein-protein interaction map is a key gateway into liver regeneration

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World Journal of Gastroenterology 2010年第28期16卷 3491-3498页

作者： chao Xie Run-Zhi Zhu Yun-Sheng Yuan Hong-Lin He Yan Yu chao Xie Qiu-Shi Huang Jin gao Wei Han School of Agriculture and Biology Shanghai Municipality Key Laboratory of Veterinary Biotechnology Shanghai Jiao Tong University Shanghai 200240 China Department of Food Science Cornell University Ithaca NY 14853 United States Laboratory of Regeneromics School of Pharmacy Shanghai Jiao Tong UniversityShanghai 200240 China

Recent studies indicate that the process of liver regeneration involves multiple signaling pathways and a variety of genes,cytokines and growth factors. Protein-protein interactions(PPIs)play a role in nearly all events that take place within the cell and PPI maps should be helpful in further understanding the process of liver *** this review,we discuss recent progress in understanding the PPIs that occur during liver regeneration especially those in the transforming growth factorβsignaling *** believe the use of large-scale PPI maps for integrating the information already known about the liver regeneration is a useful approach in understanding liver regeneration from the standpoint of systems biology.

关键词： Liver regeneration Protein-protein interaction Protein-protein interaction maps Transforming growth factorβ

Multi-Scale PIIFD for Registration of Multi-Source Remote Sensing Images

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Journal of Beijing Institute of Technology 2021年第2期30卷 113-124页

作者： Chenzhong gao Wei Li School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China Beijing Key Laboratory of Fractional Signals and Systems Beijing Institute of TechnologyBeijing 100081China

This paper aims at providing multi-source remote sensing images registered in geometric space for image *** on the characteristics and differences of multi-source remote sensing images,a feature-based registration algorithm is *** key technologies include image scale-space for implementing multi-scale properties,Harris corner detection for keypoints extraction,and partial intensity invariant feature descriptor(PIIFD)for keypoints ***,a multi-scale Harris-PIIFD image registration algorithm framework is *** experimental results of fifteen sets of representative real data show that the algorithm has excellent,stable performance in multi-source remote sensing image registration,and can achieve accurate spatial alignment,which has strong practical application value and certain generalization ability.

关键词： image registration multi-source remote sensing scale-space Harris corner partial intensity invariant feature descriptor(PIIFD)

MHGCN:Multiview Highway Graph Convolutional Network for Cross-Lingual Entity Alignment

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Tsinghua Science and Technology 2022年第4期27卷 719-728页

作者： Jianliang gao Xiangyue Liu Yibo Chen Fan Xiong School of Computer Science and Engineering Central South UniversityChangsha 410083China Information and Communication Branch State Grid Hunan Electric Power Company LimitedChangsha 410004China

Knowledge graphs(KGs)provide a wealth of prior knowledge for the research on social *** entity alignment aims at integrating complementary KGs from different languages and thus benefits various knowledge-driven social network *** entity alignment methods often take an embedding-based approach to model the entity and relation embedding of ***,these studies mostly focus on the information of the entity itself and its structural features but ignore the influence of multiple types of data in *** this paper,we propose a new embedding-based framework named multiview highway graph convolutional network(MHGCN),which considers the entity alignment from the views of entity semantic,relation semantic,and entity *** learn the structural features of an entity,the MHGCN employs a highway graph convolutional network(GCN)for entity embedding in each *** addition,the MHGCN weights and fuses the multiple views according to the importance of the embedding from each view to obtain a better entity *** alignment entities are identified based on the similarity of entity *** experimental results show that the MHGCN consistently outperforms the state-of-the-art alignment *** research also will benefit knowledge fusion through cross-lingual KG entity alignment.

关键词： knowledge graph entity alignment graph convolutional network

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我国林火发生预测模型研究进展

应用生态学报 2020年第9期31卷 3227-3240页

作者：高超林红蕾胡海清宋红东北林业大学哈尔滨150040 黑龙江大学哈尔滨150080

通过文献回顾,总结了国内林火发生预测模型的研究现状,并从林火发生驱动因子、林火发生概率预测模型、林火发生频次预测模型和模型检验方法等方面进行归纳分析。得出以下结论:1)气象、地形、植被、可燃物、人类活动等因素是影响林火发... 详细信息

通过文献回顾,总结了国内林火发生预测模型的研究现状,并从林火发生驱动因子、林火发生概率预测模型、林火发生频次预测模型和模型检验方法等方面进行归纳分析。得出以下结论:1)气象、地形、植被、可燃物、人类活动等因素是影响林火发生及模型预测精度的主要驱动因子;2)林火发生概率模型中,地理加权逻辑斯蒂回归模型考虑了变量之间的空间相关性,Gompit回归模型适宜非对称结构的林火数据,随机森林模型不需要多重共线性检验,在避免过度拟合的同时提高了预测精度,是林火发生概率预测模型的优选方法之一;3)林火发生频次模型中,负二项回归模型更适合对过度离散数据进行模拟,零膨胀模型和栅栏模型可以处理林火数据中包含大量零值的问题;4)ROC检验、AIC检验、似然比检验和Wald检验方法是林火概率和频次模型的常用检验方法。林火发生预测模型研究仍是我国当前林火管理工作的重点,预测模型的选择需要依据不同地区林火数据特点。此外,构建林火预测模型时需要考虑更多的影响因素,以提高模型预测精度;未来,需要进一步探索其他数学模型在林火发生预测中的应用,不断提高林火发生预测模型的准确度。

关键词：林火发生概率林火发生频次林火驱动因子回归模型模型检验