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A multiple heterogeneous UAVs reconnaissance mission planning and re-planning algorithm

Journal of Systems Engineering and Electronics 2022年第6期33卷 1190-1207页

作者： HU Lei XI Boqi YI Guoxing ZHAO Hui zhong jiapeng School of Astronautics Harbin Institute of TechnologyHarbin 150000China HIT(Anshan)Institute of Industrial Technology Harbin Institute of TechnologyAnshan 114000China

Reconnaissance mission planning of multiple unmanned aerial vehicles(UAVs)under an adversarial environment is a discrete combinatorial optimization problem which is proved to be a non-deterministic polynomial(NP)-complete *** purpose of this study is to research intelligent multiUAVs reconnaissance mission planning and online re-planning algorithm under various constraints in mission *** numerous targets scattered in the wide area,a reconnaissance mission planning and re-planning system is established,which includes five modules,including intelligence analysis,sub-mission area division,mission sequence planning,path smoothing,and online *** intelligence analysis module depicts the attribute of targets and the heterogeneous characteristic of UAVs and computes the number of sub-mission areas on consideration of voyage distance *** the sub-mission area division module,an improved K-means clustering algorithm is designed to divide the reconnaissance mission area into several sub-mission areas,and each sub-mission is detected by the UAV loaded with various detective *** control reconnaissance cost,the sampling and iteration algorithms are proposed in the mission sequence planning module,which are utilized to solve the optimal or approximately optimal reconnaissance *** the path smoothing module,the Dubins curve is applied to smooth the flight path,which assure the availability of the planned ***,an online re-planning algorithm is designed for the uncertain factor that the UAV is ***,reconnaissance planning and re-planning experiment results show that the algorithm proposed in this paper are effective and the algorithms designed for sequence planning have a great advantage in solving efficiency and optimality.

关键词： reconnaissance mission planning sequence planning path smoothing combination optimization

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Summer extreme precipitation patterns and synoptic-scale circulation precursors over the Tibetan Plateau

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Science China Earth Sciences 2024年第5期67卷 1625-1638页

作者： Zhiyuan DING Yao HA zhong zhong College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410073China Key Laboratory for Virtual Geographic Environment School of Geography ScienceNanjing Normal UniversityNanjing 210023China Jiangsu Collaborative Innovation Center for Climate Change School of Atmospheric SciencesNanjing UniversityNanjing 210023China

In the context of global warming,the extreme summer precipitation over the Tibetan Plateau(TP)has changed *** this study,the summer(June–August)extreme precipitation on the TP was classified into three spatial types by applying the K-means clustering method to the Third Pole Region long time-series high-resolution(1/30°)precipitation dataset(TPHi Pr,1979–2020).The characteristics of the circulation anomalies and precursors corresponding to the extreme precipitation on the TP in summer during 1979–2020 were *** results showed that the summer extreme precipitation of the TP can be categorized into northwestern(NW),southeastern(SE),and southern Himalayan(HS)types based on extreme precipitation *** NW and SE types are mainly influenced by anomalous signals in the mid-to-high latitude regions upstream of them,whereas the HS type is controlled by the localized subtropical anomalous *** the 8th day before the onset of the NW type,an anomalous cyclone was observed in the western Atlantic Ocean(60°W,50°N),which triggered the west-to-east quasi-latitudinal propagation of Rossby *** the onset day of the NW type,the upper troposphere showed positive-negative-positive geopotential height anomalies along the latitudinal 40°N from the Caspian Sea,the western part of Xinjiang,to the northeastern *** entered from the Arabian Sea along the southeastern edge of the anomalous cyclone on the southwestern TP and converged in the northwestern *** to the NW type,the precursors of the SE type appeared at higher latitudes and were more *** the 8th day before the onset of the SE type,an anomalous cyclone occurred near Greenland(60°W,70°N)and excited Rossby waves propagating *** the onset day of the SE type,the upper troposphere showed negative-positive-negative geopotential height anomalies across Eurasia from the Ural Mountains and the Iranian Plateau to the northern TP in the northwest-southeast directi

关键词： Tibetan Plateau Summer extreme precipitation Atmospheric circulation anomaly Precursor Teleconnection wave train

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Modeling and Simulation of Lithium Vacuum Evaporation Process Using COMSOL Multiphysics

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Journal of Thermal Science 2024年第1期33卷 86-100页

作者： LIAN Xuexin zhong Dawen Beijing Key Laboratory of Passive Nuclear Power Safety and Technology North China Electric Power UniversityBeijing 102206China

Based on the COMSOL Multiphysics simulation software,this study carried out modeling and numerical simulation for the evaporation process of liquid metal lithium in the vacuum free molecular flow *** motion of lithium atoms in the evaporation process was analyzed through a succession of *** on the available experimental values of the saturated vapor pressure of liquid metal lithium,the relationship between saturated vapor pressure and temperature of liquid lithium in the range of 600 K-900 K was obtained.A two-dimensional symmetric model(3.5 mm×20 mm) was established to simulate the transient evaporation process of liquid lithium at wall temperatures of 750 K,780 K,800 K,810 K,825 K,and 850 K,*** effects of temperature,the evaporation coefficient,back pressure,and length-to-diameter ratio on the evaporation process were studied;the variation trends and reasons of the molecular flux and the pressure during the evaporation process were *** the same time,the evaporation process under variable wall temperature conditions was *** research made the evaporation process of liquid lithium in vacuum molecular flow clearer,and provided theoretical support for the space reactor and nuclear fusion related fields.

关键词： free molecular flow saturated vapor pressure vacuum evaporation liquid lithium metal

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基于多磁信标的指纹匹配定位算法

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遥感学报 2022年第10期26卷 2073-2082页

作者：郑元勋李清华王常虹黄远钟佳朋哈尔滨工业大学空间控制与惯性技术研究中心哈尔滨150001 中国兵器工业集团航空弹药研究院哈尔滨150030 中核核电运行管理有限公司海盐314300 哈尔滨工业大学(鞍山)工业技术研究院鞍山114000

针对室内、地下以及障碍物较多的复杂环境中,可用导航源匮乏问题,本文提出一种利用低频时变磁场实现目标高精度位置与姿态解算的解决方案。传统时变磁场定位方法要求磁信标坐标系与目标坐标系一致且无法解算目标相对姿态角信息,同时精... 详细信息

针对室内、地下以及障碍物较多的复杂环境中,可用导航源匮乏问题,本文提出一种利用低频时变磁场实现目标高精度位置与姿态解算的解决方案。传统时变磁场定位方法要求磁信标坐标系与目标坐标系一致且无法解算目标相对姿态角信息,同时精度普遍较差。本文提出的方案在解决传统方案的局限性基础上,又提出一种基于指纹匹配的改进方案,具有穿透性好、鲁棒性强且精度高的特点。首先根据空间中测量磁场计算磁信标接收信号强度RSSI(Received Signal Strength Indicator)拟合直线,根据指纹匹配原理估计目标位置;再根据测量磁场方向矢量模型,反演解算目标姿态角信息,实现目标位置与姿态信息解算过程,研究并分析了磁信标导航系统误差来源及解决方案;最后通过对比实验,验证本文提出的算法在实验条件下,位置估计误差期望为0.069 m,姿态角估计误差期望为2.3°,且误差不随时间积累,相对于传统的磁信标导航方案具有明显优势,具有较高的工程应用价值。

关键词：位姿解算磁信标模型地下与室内导航指纹匹配算法

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FaSRnet:a feature and semantics refinement network for human pose estimation

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Frontiers of Information Technology & Electronic Engineering 2024年第4期25卷 513-526页

作者： Yuanhong zhong Qianfeng XU Daidi zhong Xun YANG Shanshan WANG School of Microelectronics and Communication Engineering Chongqing UniversityChongqing 400044China Bioengineering College of Chongqing University Chongqing UniversityChongqing 400044China School of Information Science and Technology University of Science and Technology of ChinaHefei 230039China Institutes of Physical Science and Information Technology Anhui UniversityHefei 230039China

Due to factors such as motion blur,video out-of-focus,and occlusion,multi-frame human pose estimation is a challenging *** temporal consistency between consecutive frames is an efficient approach for addressing this ***,most methods explore temporal consistency through refinements of the final *** heatmaps contain the semantics information of key points,and can improve the detection quality to a certain ***,they are generated by features,and feature-level refinements are rarely *** this paper,we propose a human pose estimation framework with refinements at the feature and semantics *** align auxiliary features with the features of the current frame to reduce the loss caused by different feature *** attention mechanism is then used to fuse auxiliary features with current *** terms of semantics,we use the difference information between adjacent heatmaps as auxiliary features to refine the current *** method is validated on the large-scale benchmark datasets PoseTrack2017 and PoseTrack2018,and the results demonstrate the effectiveness of our method.

关键词： Human pose estimation Multi-frame refinement Heatmap and offset estimation Feature alignment Multi-person

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Eigenvalues for the Clamped Plate Problem of L_(ν)^(2) Operator on Complete Riemannian Manifolds

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2223-2243页

作者： Ling zhong ZENG Jiangxi Provincial Center for Applied Mathematics&School of Mathematics and Statistics Jiangxi Normal UniversityNanchang 330022P.R.China

L_(ν)operator is an important extrinsic differential operator of divergence type and has profound geometric *** this paper,we consider the clamped plate problem of L2νoperator on a bounded domain of the complete Riemannian manifolds.A general formula of eigenvalues of L_(ν)^(2)operator is *** this general formula,we obtain some estimates for the eigenvalues with higher order on the complete Riemannian *** several fascinating applications,we discuss this eigenvalue problem on the complete translating solitons,minimal submanifolds on the Euclidean space,submanifolds on the unit sphere and projective *** particular,we get a universal inequality with respect to the L_(II) operator on the translating ***,it is very difficult to get universal inequalities for weighted Laplacian and even Laplacian on the complete Riemannian ***,this work can be viewed as a new contribution to universal estimate.

关键词： Mean curvature flows L_(ν)^(2)operator clamped plate problem eigenvalues Riemannian manifolds translating solitons

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Hot versus cold subduction initiation

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National Science Review 2024年第2期11卷 101-102页

作者： zhong-Hai Li Key Laboratory of Computational Geodynamics College of Earth and Planetary SciencesUniversity of Chinese Academy of Sciences

In the framework of plate tectonics, subduction initiation(SI) indicates the birth of a plate convergent boundary, which is a key point of plate tectonics and Wilson's cycle; however, its dynamic process is not well c... 详细信息

关键词： DRIVEN CRUST

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Weakly Compact Sets and Riesz Representation Theorem in Musielak Sequence Spaces

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Acta Mathematica Sinica,English Series 2024年第2期40卷 467-484页

作者： Wan zhong GONG Si Yu SHI zhong Rui SHI Department of Mathematics Anhui Normal UniversityWuhu 241000P.R.China Smeal College of Business Pennsylvania State UniversityUniversity ParkPennsylwania 16802USA Department of Mathematics Shanghai UniversityShanghai 200444P.R.China

In this work,we give some criteria of the weakly compact sets and a representation theorem of Riesz's type in Musielak sequence spaces using the ideas and techniques of sequence spaces and Musielak ***,as an immediate consequence of the criteria considered in this paper,the criteria of the weakly compact sets of Orlicz sequence spaces are deduced.

关键词： Compact set weak topology Banach space dual space Musielak sequence spaces

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Cardiovascular computed tomography in cardiovascular disease:An overview of its applications from diagnosis to prediction

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Journal of Geriatric Cardiology 2024年第5期21卷 550-576页

作者： zhong-Hua SUN Discipline of Medical Radiation Science Curtin Medical SchoolCurtin UniversityPerthAustralia Curtin Health Innovation Research Institute(CHIRI) Curtin UniversityPerth 6012Australia

Cardiovascular computed tomography angiography(CTA)is a widely used imaging modality in the diagnosis of cardiovascular *** in CT imaging technology have further advanced its applications from high diagnostic value to minimising radiation exposure to *** addition to the standard application of assessing vascular lumen changes,CTA-derived applications including 3D printed personalised models,3D visualisations such as virtual endoscopy,virtual reality,augmented reality and mixed reality,as well as CT-derived hemodynamic flow analysis and fractional flow reserve(FFRCT)greatly enhance the diagnostic performance of CTA in cardiovascular *** widespread application of artificial intelligence in medicine also significantly contributes to the clinical value of CTA in cardiovascular *** value of CTA has extended from the initial diagnosis to identification of vulnerable lesions,and prediction of disease extent,hence improving patient care and *** this review article,as an active researcher in cardiovascular imaging for more than 20 years,I will provide an overview of cardiovascular CTA in cardiovascular *** is expected that this review will provide readers with an update of CTA applications,from the initial lumen assessment to recent developments utilising latest novel imaging and visualisation *** will serve as a useful resource for researchers and clinicians to judiciously use the cardiovascular CT in clinical practice.

关键词： diagnosis cardiovascular prediction

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Analysis of gravity wave activity during stratospheric sudden warmings in the northern hemisphere

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Earth and Planetary Physics 2024年第2期8卷 415-422页

作者： XuanYun Zeng Guang zhong School of Physics and Electronic Sciences Changsha University of Science and TechnologyChangsha 410000China Key Laboratory of Geospace Environment Chinese Academy of SciencesUniversity of Science&Technology of ChinaHefei 230026China

Due to the significant changes they bring to high latitude stratospheric temperature and wind,stratospheric sudden warmings(SSWs)can have an impact on the propagation and energy distribution of gravity waves(GWs).The variation characteristics of GWs during SSWs have always been an important *** temperature data from January to March in 2014−2016,provided by the Constellation Observing System for Meteorology,Ionosphere and Climate(COSMIC)mission,we have analyzed global GW activity at 15−40 km in the Northern Hemisphere during SSW *** the SSWs that we studied,the stratospheric temperature rose in one or two longitudinal regions in the Northern Hemisphere;the areas affected extended to the east of 90°*** these SSWs,the potential energy density(E_(p)of GWs expanded and covered a larger range of longitude and altitude,exhibiting an eastward and downward *** E_(p)usually increased,while partially filtered by the eastward zonal *** zonal winds weakened or turned westward,E_(p)began to *** SSWs,the E_(p)usually *** observations can serve as a reference for analyzing the interaction mechanism between SSWs and GWs in future work.

关键词： stratospheric sudden warming gravity wave wind filter

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