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异构无人系统协同控制研究进展

工程科学学报 2025年第1期47卷 66-78页

作者：郭兴李擎姚其家鲁小雅北京科技大学自动化学院北京100083 工业过程知识自动化教育部重点实验室北京100083

面对复杂化、多样化和立体化的任务需求,异构无人系统将空、地、海跨域优势互补,最大化提升系统各方面能力,为未来协同作战和智慧民生提供有力的技术保障.首先,梳理了国内外在跨域协同领域出台的推动性文件,介绍了异构无人系统在军用、... 详细信息

面对复杂化、多样化和立体化的任务需求,异构无人系统将空、地、海跨域优势互补,最大化提升系统各方面能力,为未来协同作战和智慧民生提供有力的技术保障.首先,梳理了国内外在跨域协同领域出台的推动性文件,介绍了异构无人系统在军用、科研院所和民用等三方面的实际应用.其次,针对异构无人系统关键技术之一的协同控制,分别阐述了异构无人系统协同控制在一致性、轨迹跟踪和编队‒合围等三方面的最新进展.此外,还特别讨论了在不同通信条件下协同控制所面临的挑战和解决方案.其中,由于一致性和轨迹跟踪存在上层控制理论性和下层控制可行性的区别,进一步从滑模控制、自适应控制、反步控制和自适应动态规划等四方面对轨迹跟踪研究展开阐述.然后,为了更好地促进异构无人系统协同控制在实际中的应用,通过总结前人相关工作,讨论了其在多约束控制与实时性、多任务切换控制和跨域通信下稳定性等三方面亟需解决的技术瓶颈.最后,综合异构无人系统协同控制研究现状和实际需求来看,指出了其在深度强化学习与分布式博弈、人机交互以及反群体智能等三方面的发展趋势.

关键词：异构无人系统协同控制跨域协同任务需求技术瓶颈

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Study of damage to a high concrete dam subjected to underwater shock waves

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Earthquake Engineering and Engineering Vibration 2014年第2期13卷 337-346页

作者： lu lu Li Xin Zhou Jing Faculty of Architecture and Civil Engineering Huaiyin Institute of Technology The State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology

To study the effect of a strong underwater shock wave on a concrete dam, this research aims to improve hammer impact methods in model tests. Six 1:200 scale models were designed and tested under distributed impact loads. A device was deployed for a direct measurement of the impact force at the upstream face of the dams. The model dam bases were anchored to prevent displacement. The experimental results indicate that the top part of the concrete dam is a weak zone, and the impact failure initiates with a fracture on the top of the dam. The peak value of impact stress increases when the second crack appears in the concrete dam from the upstream face to the downstream face. And, the level of the second crack in the dam body is lower as the peak value of impact stress increases. In this study, dynamic analysis was conducted by calculating the results to verify the effectiveness of a device to directly measure the impact force. This method may be used to approximately forecast the damage of concrete dam and may also be useful in other engineering applications.

关键词： underwater shock wave hammer impact impact force high concrete gravity dam forecast damage

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基于特征增强的双重注意力去雾网络

电光与控制 2025年第1期32卷 15-20,67页

作者：陈海秀黄仔洁陆康陆成何珊珊房威志卢海涛陈子昂南京信息工程大学自动化学院南京210000 南京信息工程大学、江苏省大气环境与装备技术协同创新中心南京210000

针对现有去雾方法处理的图像细节模糊和色彩偏差等问题,提出了一种基于特征增强的双重注意力去雾网络。该网络采用编码器-解码器结构,设计了一个双重注意力特征增强模块,其中,利用Ghost模块替代非线性卷积,实现模型轻量化处理,通过RFB... 详细信息

针对现有去雾方法处理的图像细节模糊和色彩偏差等问题,提出了一种基于特征增强的双重注意力去雾网络。该网络采用编码器-解码器结构,设计了一个双重注意力特征增强模块,其中,利用Ghost模块替代非线性卷积,实现模型轻量化处理,通过RFB充分融合不同尺度的特征,实现均匀去雾,引入双重注意力实现信息跨通道与空间交互,保证模型性能和抑制噪声特征。使用RESIDE数据集对网络进行训练和测试。实验结果表明,所提算法在主观视觉和客观评价指标上均有优异表现,能有效地提升网络的特征提取能力,实现对不同场景雾图的色彩恢复,增强图像的对比度和清晰度。

关键词：图像去雾特征增强并行分支结构多尺度映射注意力机制

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Current Progress of Mechanical Properties of Metals with Nano-scale Twins

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Journal of Materials Science & Technology 2008年第4期24卷 473-482页

作者： Lei lu Shenyang National Laboratory for Materials Science （SYNL） Institute of Metal Research Chinese Academy of SciencesShenyang 110016 China

Focus on face-centered cubic （fcc） metals with nano-scale twins lamellar structure, this paper presents a brief overview of the recent progress made in improving mechanical properties, including strength, ductility, work hardening, strain rate sensitivities, and in mechanistically understanding the underling deformation mechanisms. Significant developments have been achieved in nano-twinned fcc metals with a combination of high strength and considerable ductility at the same time, enhanced work hardening ability and enhanced rate sensitivity. The findings elucidate the role of interactions between dislocations and twin boundaries （TBs） and their contribution to the origin of outstanding properties. The computer simulation analysis accounts for high plastic anisotropy and rate sensitivity anisotropy by treating TBs as internal interfaces and allowing special slip geometry arrangements that involve soft and hard modes of deformation. Parallel to the novel mechanical behaviors of the nano-twinned materials, the investigation and developments of nanocrystalline materials are also discussed in this overview for comparing the contribution of grain boundaries/TBs and grain size/twin lamellar spacing to the properties. The recent advances in the experimental and computational studies of plastic deformation of the fcc metals with nano-scale twin lamellar structures provide insights into the possible means of optimizing comprehensive mechanical properties through interfacial engineering.

关键词： Nanostructured metallic materials Twin boundary Strengthening Ductility Rate sensitivity Deformation mechanism

Clustering-based topical Web crawling using CFu-tree guided by link-context

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Frontiers of Computer Science 2014年第4期8卷 581-595页

作者： lu LIU College of Computer Science and Technology Jilin University Changchun 130012 China Department of Computer Science University of Illinois at Urbana-Champaign Urbana IL 61801 USA

Topical Web crawling is an established technique for domain-specific information retrieval. However, almost all the conventional topical Web crawlers focus on building crawlers using different classifiers, which needs a lot of labeled training data that is very difficult to label manually. This paper presents a novel approach called clustering-based topical Web crawling which is utilized to retrieve information on a specific domain based on link-context and does not require any labeled training data. In order to collect domain-specific content units, a novel hierarchical clustering method called bottom-up approach is used to illustrate the process of clustering where a new data structure, a linked list in combination with CFu-tree, is implemented to store cluster label, feature vector and content unit. During clustering, four metrics are presented. First, comparison variation （CV） is defined to judge whether the closest pair of clusters can be merged. Second, cluster impurity （CIP） evaluates the cluster error. Then, the precision and recall of clustering are also presented to evaluate the accuracy and comprehensive degree of the whole clustering process. Link-context extraction technique is used to expand the feature vector of anchor text which improves the clustering accuracy greatly. Experimental results show that the performance of our proposed method overcomes conventional focused Web crawlers both in Harvest rate and Target recall.

关键词： topical Web crawling comparison variation (CV) cluster impurity (CIP) CFu-tree link-context clustering

第一性原理对M@B_(12)N_(12)(M=Sc-Zn)团簇结构和性质的研究

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原子与分子物理学报 2025年第4期42卷 93-99页

作者：张颂程露吴学科凯里学院理学院凯里556011

利用基于密度泛函理论的第一性原理对M@B_(12)N_(12)(M=Sc-Zn)团簇的几何、电子结构,电偶极性和红外吸收光谱进行详细的研究.结果显示:当B_(12)N_(12)团簇内嵌过渡金属原子后,虽然结构稳定性稍稍降低,但其化学活性得到提高,摩尔体积明... 详细信息

利用基于密度泛函理论的第一性原理对M@B_(12)N_(12)(M=Sc-Zn)团簇的几何、电子结构,电偶极性和红外吸收光谱进行详细的研究.结果显示:当B_(12)N_(12)团簇内嵌过渡金属原子后,虽然结构稳定性稍稍降低,但其化学活性得到提高,摩尔体积明显增大.过渡金属原子与B_(12)N_(12)结合的过程中,除Cu和B原子外,剩余金属与N原子的Mulliken电荷出现负值.另外,金属原子的加入,不仅增加电偶极矩和极化率的值,还促使其红外吸收光谱发生红移.

关键词：团簇结构性质第一性原理

New methods and progress in research on the origins and evolution of prehistoric agriculture in China

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Science China Earth Sciences 2017年第12期60卷 2141-2159页

作者： lu HouYuan Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Center for Excellence in Tibetan Plateau Earth Science Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

China is one of the main global centers of origin of agriculture. Foxtail millet(Setaria italica), common millet(Panicum miliaceum), and rice(Oryza sativa) were the first crops to be domesticated in China. There remain many uncertainties and controversies in our current understanding of the chronology, locations, and plant types at the origins and the process of evolution of prehistoric millet and rice farming, and their relationships with climate change and human adaptation. This review summarizes the research progress made by Chinese scientists over the last decade on the origins and evolution of prehistoric agriculture. It highlights novel techniques and methods for identifying early crop remains, including plant macrofossils(carbonized seeds, spikelets), microfossils(phytoliths, calciphytoliths, starch, pollen), and biomarkers; new evidence on the origins, development, and spread of early agriculture; and research related to climate and environmental changes. Further, we pinpoint and discuss existing challenges and potential opportunities for further in-depth investigation of the origins and evolution of agriculture and the adaption of human activities to climate change.

关键词： Origins of agriculture Dry-farming crops(millets) Rice Phytoliths Starch Microfossils Biomarkers

SED：An SDN-Based Explicit-Deadline-Aware TCP for Cloud Data Center Networks

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Tsinghua Science and Technology 2016年第5期21卷 491-499页

作者： Yifei lu School of Computer Science and Engineering Nanjing University of Science and Technology Nanjing 210094 China the Key Laboratory of Computer Network and Information Integration (Southeast University) Ministry of Education Nanjing 210096 China

Cloud data centers now provide a plethora of rich online applications such as web search, social networking, and cloud computing. A key challenge for such applications, however, is to meet soft real-time constraints. Due to the deadline-agnostic congestion control in Transmission Control Protocol（TCP）, many deadline-sensitive flows cannot finish transmission before their deadlines. In this paper, we propose an SDNbased Explicit-Deadline-aware TCP（SED） for cloud Data Center Networks（DCN）. SED assigns a base rate for non-deadline flows first and gives spare bandwidth to the deadline flows as much as possible. Subsequently,a Retransmission-enhanced SED（RSED） is introduced to solve the packet-loss timeout problem. Through our experiments, we show that SED can make flows meet deadlines effectively, and that it significantly outperforms previous protocols in the cloud data center environment.

关键词： data center networks SDN TCP congestion deadline-aware

ASYMPTOTIC RESULTS FOR OVER-DISPERSED OPERATIONAL RISK BY USING THE ASYMPTOTIC EXPANSION METHOD

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Journal of Systems Science & Complexity 2014年第3期27卷 524-536页

作者： lu Zhaoyang School of Science Engineering University of Chinese Armed Police Forces

In this paper, the author considers a new Loss-distribution-approach model, in which the over-dispersed operational risks are modeled by the compound negative binomial process. In the single dimensional case, asymptotic expansion for the quantile of compound negative binomial process is explored for computing the capital charge of a bank for operational risk. Moreover, when the dependence structure between different risk cells is modeled by the Frank copula, this approach is extended to the multi-dimensional setting. A practical example is given to demonstrate the effectiveness of approximation results.

关键词： Asymptotic expansion multivariate dependence operational risk over-dispersed valueat risk.