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International Journal of Minerals,Metallurgy and Materials 2021年第4期28卷 590-602页

作者： Lang Liu jie Xin chao Huan yu-jiao Zhao Xiang Fan Li-jie Guo KI-IL Song Energy School Xi’an University of Science and TechnologyXi’an 710054China Key Laboratory of Western Mines and Hazards Prevention Ministry of Education of ChinaXi’an 710054China School of Highway Chang’an UniversityXi’an 710064China Beijing General Research Institute of Mining&Metallurgy Beijing 100160China Department of Civil Engineering Inha UniversityIncheon 402-751South Korea

Several special mechanical properties,such as dilatancy and compressibility,of cemented paste backfill(CPB)are controlled by its internal microstructure and *** mesoscopic structure changes of CPB during the development process were *** the basis of the scanning electron microscopy(SEM)and mechanical test results of CPB,the particle size information of CPB was extracted,and a two-dimensional particle flow code(PFC)model of CPB was established to analyze the evolution rule of mesoscopic parameters during CPB *** embedded FISH language in PFC was used to develop a program for establishing a PFC model on the basis of the SEM *** mesoscopic parameters of CPB samples at different curing times,such as coordination number(C_(n)),contact force chain,and rose diagram,were obtained by recording and loading and used to analyze the intrinsic relationship between mesoscopic parameter variations and macroscopic mechanical response during CPB *** is of considerable significance to establish the physical model of CPB using the PFC to reveal the mesoscopic structure of CPB.

关键词： cemented paste backfill particle flow code method mesoscopic parameters fabric

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基于改进DGCNN的树木点云分割方法

南京农业大学学报 2025年第1期48卷 240-248页

作者：刘超卜鑫荣刘慧杨官学沈跃徐婕江苏大学电气信息工程学院江苏镇江212000

[目的]通过目标分割为果园喷雾机提供树木的表征信息,使喷雾机能够实现精准喷雾。在分割过程中,对苗圃中的树冠、树干等不同部位进行分割,可以帮助喷雾机对喷雾部分对靶,在果园或苗圃景观中实现自动导航以及精准喷药等操作。与图片相比... 详细信息

[目的]通过目标分割为果园喷雾机提供树木的表征信息,使喷雾机能够实现精准喷雾。在分割过程中,对苗圃中的树冠、树干等不同部位进行分割,可以帮助喷雾机对喷雾部分对靶,在果园或苗圃景观中实现自动导航以及精准喷药等操作。与图片相比,点云能够更好地表征树木的三维结构并且受照明条件影响小,因此针对点云树木设计分割算法更适合应用在果园、苗圃等室外环境作业的农业机械。[方法]本文基于DGCNN提出了一种分割精度准确、参数量小的树木点云分割网络——TSNet,它可以很容易被部署在果园喷雾机上。该网络主要具有以下特点:1)该网络是基于DGCNN改进的,可以更好实现点云分割任务;2)网络引入了连续递归门控卷积模块(gnConv),可以提高树木分割的准确率;3)为避免全局信息损失并增加信息传递效率,我们设计了权重通道用于特征传递。[结果]TSNet分割树木的mIoU达到90.08%,模型大小为0.72 M,优于PointNet、PointNet++、DGCNN、CurveNet、PointMLP和D-PointNet++等常用的点云分割算法。[结论]TSNet能够为苗圃树木检测识别和农业机器人作业提供更准确的感知信息。

关键词：点云树木分割深度学习精准喷雾果园喷雾机

A bi-population immune algorithm for weapon transportation support scheduling problem with pickup and delivery on aircraft carrier deck

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Defence Technology（防务技术） 2023年第4期22卷 119-134页

作者： Fang Guo Wei Han Xi-chao Su yu-jie Liu Rong-wei Cui Naval Aviation University No.188Ermalu RoadZhifu DistrictYantai264001Shandong ProvinceChina

The weapon transportation support scheduling problem on aircraft carrier deck is the key to restricting the sortie rate and combat capability of carrier-based *** paper studies the problem and presents a novel solution *** the interference of the carrier-based aircraft deck layout on the weapon transportation route and precedence constraint into consideration,a mixed integer formulation is established to minimize the total objective,which is constituted of makespan,load variance and accumulative transfer time of support *** approach is developed for the ***,based on modeling the carrier aircraft parked on deck as convex obstacles,the path library of weapon transportation is constructed through visibility graph and Warshall-Floyd *** then propose a bi-population immune algorithm in which a population-based forward/backward scheduling technique,local search schemes and a chaotic catastrophe operator are ***,the randomkey solution representation and serial scheduling generation scheme are adopted to conveniently obtain a better *** Taguchi method is additionally employed to determine key parameters of the ***,on a set of generated realistic instances,we demonstrate that the proposed algorithm outperforms all compared algorithms designed for similar optimization problems and can significantly improve the efficiency,and that the established model and the bi-population immune algorithm can effectively respond to the weapon support requirements of carrier-based aircraft under different sortie missions.

关键词： Carrier-based aircraft Weapon transportation support scheduling Pickup and delivery Bi-population immune algorithm

Recent progress on photoactive nonprecious transition-metal complexes

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Science China Chemistry 2025年第1期 46-95页

作者： Zhong-Liang Gong Hong-jie Zhang Yan Cheng Jianxun Liu yuhan Ai Yaqin Li Zhihui Feng Qiong Zhang Shaolong Gong Yong Chen Chang-Jiang Yao yuan-yuan Zhu Liang-Jin Xu yu-Wu Zhong CAS Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences State Key Laboratory of Structural Cemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences School of Chemistry and Chemical Engineering Anhui Key Laboratory of Advanced Catalytic Materials and Reaction EngineeringHefei University of Technology State Key Laboratory of Explosion Science and Safety Protection School of Mechatronical Engineering Beijing Institute of Technology College of Chemistry and Molecular Sciences Hubei Key Lab on Organic and Polymeric Optoelectronic Materials Wuhan University School of Chemistry and Chemical Engineering Anhui University Key Laboratory of Photochemical Conversion and Optoelectronic Materials & CAS-HKU Joint Laboratory on New Materials Technical Institute of Physics and Chemistry Chinese Academy of Sciences

Photoactive complexes of nonprecious transition metals, mainly including those in the first-row and partially the second-row of the Periodic table of elements, have received increasing attention in view of their low cost and long-term sustainability. They are recognized as promising alternatives to noble transition metal complex congeners that have been extensively studied in optoelectronic devices, artificial photosynthesis, photocatalysis, biodiagnostics, and therapeutics, etc. This review is devoted to a comprehensive summary on the classical and recent advances on photoactive nonprecious transition metal complexes, including photoactive Zr, V, Cr, Mo, and W complexes, Mn complexes and hybrids, Fe, Co, Ni, and Cu complexes, and Zn and Cd complexes and hybrids. A particular focus is given on the molecular design, modulation of photophysical and photochemical properties, and applications of the representative and lately-developed nonprecious metal complexes. In addition, a perspective on the future development in this field is provided at the end of this review.

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Clinical characteristics,diagnosis,and treatment of COVID-19:A case report

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World Journal of Clinical Cases 2020年第11期8卷 2325-2331页

作者： Yan-Fei He Shi-jie Lian yu-chao Dong Cadre Health Care Department The Sixth Medical CenterChinese PLA General HospitalBeijing 100048China Department of Respiratory and Critical Care Medicine Changhai HospitalNaval Medical UniversityShanghai 200433China

BACKGROUND Since December 2019,many cases of pneumonia caused by novel coronavirus have been discovered in Wuhan,China,and such cases have spread nationwide *** present,coronavirus disease 2019(COVID-19)is a worldwide *** are the clinical features of this disease?What is the clinical diagnosis and how should such patients be treated?As a clinician,mastery of the clinical characteristics,basic diagnosis,and treatment methods of COVID-19 are required to provide help to *** SUMMARY A 42-year-old male patient with a cough lasting 6 d without obvious cause,as well as fever and fatigue for 1 d,was admitted to Hankou Hospital on January 22,2020 and transferred to Huoshenshan Hospital on February *** main clinical symptoms were dry cough,fatigue,and *** was diagnosed with *** the 4th d of admission,the patient’s condition gradually worsened,with increased respiratory rate and body *** blood lymphocytes decreased *** the 8th d of admission,the patient’s highest temperature was 40.7°C,and oxygen saturation was 83%despite high-flow oxygen *** computed tomography results showed that the virus progressed *** number of lesions significantly increased with expanded scope and increased *** distribution of lesions advanced from peripheral to *** addition to nasal catheter oxygen inhalation and symptomatic support,antiviral drugs were used throughout the *** January 22,oseltamivir phosphate capsules were given orally(75 mg,twice daily)for 6 *** January 24,three tablets of lopinavir and ritonavir were added orally(twice daily).After 6 d,this was changed to 0.2 g(two tablets)arbidol,taken orally(three times daily)for 5 *** the severe stage,methylprednisolone was given(40 mg)once every 12 h,immunoglobulin(20 g)was administered by intravenous drip infusion once daily,and thymosin(1.6 mg)was injected subcutaneously once daily combined with *** Februar

关键词： COVID-19 SARS-CoV-2 Clinical characteristics Diagnosis and treatment Young adults Case report

Minimal role mining method for Web service composition

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第5期11卷 328-339页

作者： chao HUANG Jian-ling SUN Xin-yu WANG yuan-jie SI Department of Computer Science and Technology Zhejiang University Hangzhou 310027 China

Web service composition is a low cost and efficient way to leverage the existing resource and *** current Web service composition implementations,the issue of how to define the role for a new composite Web service has been little *** the access control policy for a new composite Web service always causes substantial administration overhead from the security ***,the distributed nature of Web service based applications makes traditional role mining methods *** this paper,we analyze the minimal role mining problem for Web service composition,and prove that this problem is *** propose a sub-optimal greedy algorithm based on the analysis of necessary role mapping for interoperation across multiple *** shows the effectiveness of our algorithm,and compared to the existing methods,our algorithm has significant performance *** also demonstrate the practical application of our method in a real agent based Web service *** results show that our method could find the minimal role mapping efficiently.

关键词： Web service composition Role base access control(RBAC) Role mining Access control policy Role mapping Web service security

适变与应变:“十五五”时期人口发展规划的新格局、新挑战及其实践路径

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河北学刊 2025年第1期45卷 130-139页

作者：陆杰华冯雨欣北京大学中国社会与发展研究中心北京大学社会学系

“十五五”时期是中国基本实现社会主义现代化承上启下的关键时期,同时也是人口发展深度转型的重要节点。“十五五”人口发展规划的制定必须准确识别人口规模、结构、素质、分布等要素呈现的趋势性变化,及时把握当前人口发展的潜在机遇... 详细信息

“十五五”时期是中国基本实现社会主义现代化承上启下的关键时期,同时也是人口发展深度转型的重要节点。“十五五”人口发展规划的制定必须准确识别人口规模、结构、素质、分布等要素呈现的趋势性变化,及时把握当前人口发展的潜在机遇和堵点难点,根据人口发展新格局适时调整应变思路,不断推进人口自身均衡发展,以及人口与经济社会、资源环境的协调发展。从长远来看,人口发展规划的制定还需要纵向锚定人口高质量发展的战略目标,形成应对未来人口发展新变化的超前预案。

关键词： “十五五” 人口发展规划人口高质量发展适变与应变

Experimental symmetric private information retrieval with measurement-device-independent quantum network

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Light(Science & Applications) 2022年第10期11卷 2399-2405页

作者： chao Wang Wen yu Kon Hong jie Ng Charles C.-W.Lim Department of Electrical&Computer Engineering National University of SingaporeSingaporeSingapore Centre for Quantum Technologies National University of SingaporeSingaporeSingapore

Secure information retrieval is an essential task in today's highly digitised *** some applications,it may be necessary that user query's privacy and database content's security are *** these settings,symmetric private information retrieval(SPIR)could be employed,but its implementation is known to be demanding,requiring a private key-exchange network as the base ***,we report for the first time a realisation of provably-secure SPIR supported by a quantum-secure key-exchange *** SPIR scheme looks at biometric security,offering secure retrieval of 582-byte fingerprint files from a database with 800 *** experimental results clearly demonstrate the feasibility of SPIR with quantum secure communications,thereby opening up new possibilities in secure distributed data storage and cloud computinq over the future Quantum Internet.

关键词： database network quantum

Seismic response of large-span spatial structures under multi-support and multidimensional excitations including rotational components

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Earthquake Engineering and Engineering Vibration 2021年第1期20卷 141-159页

作者： Zhang jie Li Hongnan Li chao State Key Laboratory of Coastal and Offshore Engineering Faculty of Infrastructure EngineeringDalian University of TechnologyDalian 116024China School of Civil Engineering Shenyang Jianzhu UniversityShenyang 110168China

To achieve rational and precise seismic response predictions of large span spatial structures(LSSSs),the inherent non-uniformity and multidimensionality characteristics of earthquake ground motions should be properly taken into ***,due to the limitations of available earthquake stations to record seismic rotational components,the effects of rocking and torsional earthquake components are commonly neglected in the seismic analyses of *** this study,a newly developed method to extract the rocking and torsion components at any point along the area of a deployed dense array from the translational earthquake recordings is applied to obtain the rotational seismic inputs for a *** numerical model of an actual LSSS,the Dalian International Conference Center(DICC),is developed to study the influences of multi-support and multidimensional excitations on the seismic responses of *** numerical results reveal that the non-uniformity and multidimensionality of ground motion input can considerably affect the dynamic response of the *** specific degree of influence on the overall and local structural displacements,deformations and forces are comprehensively investigated and discussed.

关键词： large-span spatial structures seismic responses multi-support multidimensional rotational components

A high-order scheme based on lattice Boltzmann flux solver for viscous compressible flow simulations

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Applied Mathematics and Mechanics(English Edition) 2022年第10期43卷 1601-1614页

作者： Jian QIN jie WU chao MA State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing210016China Key Laboratory of Unsteady Aerodynamics and Flow Control Ministry of Industry and Information TechnologyNanjing University of Aeronautics and AstronauticsNanjing210016China Department of Aerodynamics Nanjing University of Aeronautics and AstronauticsNanjing210016China

In this paper,a high-order scheme based on the lattice Boltzmann flux solver(LBFS)is proposed to simulate viscous compressible *** flux reconstruction(FR)approach is adopted to implement the spatial *** LBFS is employed to compute the inviscid flux by using the local reconstruction of the lattice Boltzmann equation solutions from macroscopic flow ***,a switch function is used in LBFS to adjust the magnitude of the numerical ***,it is more beneficial to capture both strong shock waves and thin boundary ***,the viscous flux is computed according to the local discontinuous Galerkin *** typical compressible viscous problems,including manufactured solution case,lid-driven cavity flow,supersonic flow around a cylinder and subsonic flow over a NACA0012 airfoil,are simulated to demonstrate the accuracy and robustness of the proposed FR-LBFS.

关键词： high-order method flux reconstruction lattice Boltzmann flux solver(LBFS) viscous compressible flow