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Influence of Incomplete Soil Plugs on Bearing Capacities of Bucket Foundations in Clay

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China Ocean Engineering 2024年第1期38卷 144-155页

作者： LI Hui-shan LIU Run YANG xu LIAN Ji-jian State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation Tianjin UniversityTianjin 300072China School of Civil Engineering Tianjin UniversityTianjin 300072China Institute of Marine Energy and Intelligent Construction Tianjin University of TechnologyTianjin 300384China

Due to the uneven seabed and heaving of soil during pumping,incomplete soil plugs may occur during the installation of bucket foundations,and the impacts on the bearing capacities of bucket foundations need to be *** this paper,the contact ratio(the ratio of the top diameter of the soil plug to the diameter of the bucket)and the soil plug ratio(the ratio of the soil heave height to the skirt height)are defined to describe the shape and size of the incomplete soil ***,finite element models are established to investigate the bearing capacities of bucket foundations with incomplete soil plugs and the influences of the contact ratios,and the soil plug ratios on the bearing capacities are *** results show that the vertical bearing capacity of bucket foundations in homogeneous soil continuously improves with the increase of the contact ***,in normally consolidated soil,the vertical bearing capacity barely changes when the contact ratio is smaller than 0.75,while the bearing capacity suddenly increases when the contact ratio increases to 1 due to the change of failure *** contact ratio hardly affects the horizontal bearing capacity of bucket ***,the moment bearing capacity improves with the increase of the contact ratio for small aspect ratios,but hardly varies with increasing contact ratio for aspect ratios larger than ***,the reduction coefficient method is proposed based on this analysis to calculate the bearing capacities of bucket foundations considering the influence of incomplete soil *** comparison results show that the proposed reduction coefficient method can be used to evaluate the influences of incomplete soil plug on the bearing capacities of bucket foundations.

关键词： bucket foundation incomplete soil plug uniaxial bearing capacity contact ratio soil plug ratio

Indexing dynamic encrypted database in cloud for efficient secure k-nearest neighbor query

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Frontiers of Computer Science 2024年第1期18卷 187-198页

作者： Xingxin LI Youwen ZHU Rui xu jian WANG Yushu ZHANG College of Computer Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016China Department of Mathematical Informatics University of TokyoTokyo 113-8654Japan Guangxi Key Laboratory of Trusted Software Guilin University of Electronic TechnologyGuilin 541004China School of Computer Science China University of GeosciencesWuhan 430074China

Secure k-Nearest Neighbor(k-NN)query aims to find k nearest data of a given query from an encrypted database in a cloud server without revealing privacy to the untrusted cloud and has wide applications in many areas,such as privacy-preservingmachine elearning gand secure biometric *** solutions have been put forward to solve this challenging ***,the existing schemes still suffer from various limitations in terms of efficiency and *** this paper,we propose a new encrypt-then-index strategy for the secure k-NN query,which can simultaneously achieve sub-linear search complexity(efficiency)and support dynamical update over the encrypted database(flexibility).Specifically,we propose a novel algorithm to transform the encrypted database and encrypted query points in the *** indexing the transformed database using spatial data structures such as the R-tree index,our strategy enables sub-linear complexity for secure k-NN queries and allows users to dynamically update the encrypted *** the best of our knowledge,the proposed strategy is the first to simultaneously provide these two *** theoretical analysis and extensive experiments,we formally prove the security and demonstrate the efficiency of our scheme.

关键词： cloud computing secure k-NN query sub-linear complexity dynamicupdate

Difference and Inheritance of the Sterility Maintenance of CMS in Indica Rice

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Agricultural Sciences in China 2002年第8期1卷 945-948页

作者： xu jian-hong and xuE qing-zhong( Department of Agronomy, College of Agriculture and Biotechnology Zhejiang University, Hangzhou 310029, P.R.China) Department of Agronomy College of Agriculture and Biotechnology Zhejiang University Hangzhou 310029 P.R. China

The inheritance of the sterility maintenance ability was studied for three types of CMS lines (Zhenshan97A, XieqingzaoA and II-32A) and several lines in indica rice. The result showed that the abilities to keep the male sterility of the maintainer lines strengthened obviously with the progressive backcrossing. The critical stage to maintain the sterility of CMS lines happened usually in BC5-6 generation. The selection of the recurrent parent gave an obvious influence on the pollen fertility distribution of the later generations. The author has discussed ways of improving of the maintainer lines.

关键词： Rice Maintainer Line Cytoplasm male sterile (CMS) Inheritance

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“一五”时期的投资与制度变革

当代中国史研究 2005年第6期12卷 29-38页

作者：徐建青中国社会科学院经济研究所

“一五”期间,我国资源供求状况及其配置方式发生巨大变化,这些变化与这一时期的投资过热和经济波动存在必然联系.“一五”时期的投资是个连续大起大落的过程,两次冒进间隔时间短,这在建国以来的投资史上是少见的.由于投资规模过大、增... 详细信息

“一五”期间,我国资源供求状况及其配置方式发生巨大变化,这些变化与这一时期的投资过热和经济波动存在必然联系.“一五”时期的投资是个连续大起大落的过程,两次冒进间隔时间短,这在建国以来的投资史上是少见的.由于投资规模过大、增长速度过快,导致生产资料和消费品供求形势全面紧张,促使国家将计划管理的力度和范围不断加大,从而加快了三大改造的步伐,全面建立起了计划经济体制.但自此也形成了追求高速度和外延、粗放型的增长方式.

关键词： “一五”计划时期投资建设制度变革

pH-responsive metal nanoparticles as high contrast theranostic agents for selective imaging and synergistic cancer therapy

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Science China Chemistry 2024年第9期67卷 3063-3070页

作者： Sichao Tian Xiaofeng He Xiao Wu Dongxue Hu qing-Hua xu Department of Chemistry National University of SingaporeSingapore 117543Singapore National University of Singapore(Suzhou)Research Institute Suzhou 215123China Institute of Medicinal Plant Development Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China Department of Biological Sciences Faculty of ScienceNational University of SingaporeSingapore 117558Singapore

The low signal-to-noise ratio(S/N)and single functionality of fluorescence imaging agents have limited their practical *** two-photon excitation(2PE)imaging probes are highly desirable in vivo with larger imaging depth,minor autofluorescence background,and less ***,we developed responsive aggregated gold nanoparticles(Au NPs)as high contrast 2PE imaging agents,capable of emitting red fluorescence upon excitation of near-infrared(NIR)laser and possessing a high signal-to-noise ratio(S/N of 2,475).By forming aggregates in situ inside tumor tissue,doxorubicin hydrochloride(DOX)-loaded mix-charged gold nanoparticles(DOX-MC-Au NPs)were utilized to act as selective fluorescence imaging probes and precise therapy *** high-contrast theranostic agents offer a promising potential for precise cancer imaging and therapy,which might open a new venue to multifunctional and noninvasive theranostics.

关键词： metal nanoparticles two-photon excitation high contrast imaging agents fluorescence imaging cancer therapy

Influence of pore structure heterogeneity on channeling channels during hot water flooding in heavy oil reservoir based on CT scanning

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Petroleum Science 2024年第4期21卷 2407-2419页

作者： qing-Jun Du Hao-Yu Zheng jian Hou Yong-Ge Liu jian-Fang Sun Dong Zhao State Key Laboratory of Deep Oil and Gas China University of Petroleum (East China) School of Petroleum Engineering China University of Petroleum (East China) Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology Petroleum Exploration and Production Research Institute

Hot water flooding is an effective way to develop heavy oil reservoirs. However, local channeling channels may form, possibly leading to a low thermal utilization efficiency and high water cut in the reservoir. The pore structure heterogeneity is an important factor in forming these channels. This study proposes a method that mixes quartz sand with different particle sizes to prepare weakly heterogeneous and strongly heterogeneous models through which hot water flooding experiments are *** the experiments, computer tomography(CT) scanning identifies the pore structure and micro remaining oil saturation distribution to analyze the influence of the pore structure heterogeneity on the channeling channels. The oil saturation reduction and average pore size are divided into three levels to quantitatively describe the relationship between the channeling channel distribution and pore structure heterogeneity. The zone where oil saturation reduction exceeds 20% is defined as a channeling *** scanning area is divided into 180 equally sized zones based on the CT scanning images, and threedimensional(3D) distributions of the channeling channels are developed. Four micro remaining oil distribution patterns are proposed, and the morphology characteristics of micro remaining oil inside and outside the channeling channels are analyzed. The results show that hot water flooding is more balanced in the weakly heterogeneous model, and the oil saturation decreases by more than 20% in most zones without narrow channeling channels forming. In the strongly heterogeneous model, hot water flooding is unbalanced, and three narrow channeling channels of different lengths form. In the weakly heterogeneous model, the oil saturation reduction is greater in zones with larger pores. The distribution range of the average pore size is larger in the strongly heterogeneous model. The network remaining oil inside the channeling channels is less than outside the channeling channels,

关键词： Heavy oil Hot water flooding Pore structure Channeling channels CT scanning

Proposing a machine learning approach to analyze and predict basic high-temperature properties of iron ore fines and its factors

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Journal of Iron and Steel Research International 2024年第5期31卷 1082-1094页

作者： qing-ke Sun Yao-zu Wang jian-liang Zhang Zheng-jian Liu Le-le Niu Chang-dong Shan Yun-fei Ma Institute of Artificial Intelligence University of Science and Technology BeijingBeijing100083China School of Intelligence Science and Technology University of Science and Technology BeijingBeijing100083China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China

The basic high-temperature properties of iron ore play a crucial role in optimizing sintering and ore blending,but the testing process for these properties is complex and has significant lag time,which cannot meet the actual needs of ore blending.A prediction model for the basic high-temperature properties of iron ore fines was thus proposed based on a combination of machine learning algorithms and genetic ***,the prediction accuracy of different machine learning models for the basic high-temperature properties of iron ore fines was ***,a random forest model optimized by genetic algorithms was built,further improving the prediction accuracy of the *** test results show that the random forest model optimized by genetic algorithms has the highest prediction accuracy for the lowest assimilation temperature and liquid phase fluidity of iron ore,with a determination coefficient of 0.903 for the lowest assimilation temperature and 0.927 for the liquid phase fluidity after *** trained model meets the fluctuation requirements of on-site testing and has been successfully applied to actual production on site.

关键词： Iron ore Basic high-temperature property Machine learning Random forest Genetic algorithm

O_(2) adsorption on Fe_(3)O_(4) (110) surface and effect of gangue element Al doping: combined study of binding experiment and ab initio molecular dynamics

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Journal of Iron and Steel Research International 2024年第4期31卷 810-827页

作者： Zheng-jian Liu Hui-qing jiang Yao-zu Wang jian-liang Zhang Hong-mei Qiao An-yang Zheng Fang-yu Guo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China School of Intelligence Science and Technology University of Science and Technology BeijingBeijing 100083China Beijing Shougang Co. Ltd.Qian'an 064404HebeiChina Department of Physics National University of Defense TechnologyChangsha 410128HunanChina

At high temperature,the chemical reaction mechanism at the interface of magnetite and the influence mechanism of gangue element Al on the oxidation performance of magnetite are not *** addition,due to the limitation of existing experimental equipment,it is difficult to clarify the interface reaction mechanism in the oxidation process and the influence mechanism of Al on the surface oxidation reaction of Fe_(3)O_(4) at an atomic scale at high *** surface oxidation reaction mechanism of magnetite and the influence mechanism of Al on the oxidation of magnetite were studied by experiments and AIMD(ab initio molecular dynamics).The experimental results show that the existence of Al_(2)O_(3) will reduce the initial oxidation temperature and comprehensive oxidation performance of *** AIMD results show that aluminum can accelerate the interface reaction rate of Fe_(3)O_(4) in the high-temperature oxidation atmosphere,but the strong Al-O binding ability is not conducive to the transfer of O atoms in the oxidation process.

关键词： Ironmaking Magnetite oxidation Interface reaction Adsorption-Gangue aluminum AIMD

Review of bio-inspired image sensors for efficient machine vision

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Advanced Photonics 2024年第2期6卷 7-19页

作者： Wenhao Tang qing Yang Hang xu Yiyu Guo Jiqiang Zhang Chunfang Ouyang Leixin Meng xu Liu Zhejiang Laboratory Research Center for Frontier Fundamental StudiesHangzhouChina Zhejiang University College of Optical Science and EngineeringState Key Laboratory of Extreme Photonics and InstrumentationHangzhouChina ZJU-Hangzhou Global Scientific and Technological Innovation Center HangzhouChina Shanghai Jiao Tong University Chip Hub for Integrated Photonics Xplore(CHIPX)WuxiChina

With the rapid development of sensor networks,machine vision faces the problem of storing and computing massive *** human visual system has a very efficient information sense and computation ability,which has enlightening significance for solving the above problems in machine *** review aims to comprehensively summarize the latest advances in bio-inspired image sensors that can be used to improve machine-vision processing *** briefly introducing the research background,the relevant mechanisms of visual information processing in human visual systems are briefly discussed,including layerby-layer processing,sparse coding,and neural ***,the cases and performance of image sensors corresponding to various bio-inspired mechanisms are ***,the challenges and perspectives of implementing bio-inspired image sensors for efficient machine vision are discussed.

关键词： bio-inspired image sensor machine vision layer-by-layer processing sparse coding neural adaptation