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环形月池对海洋核能平台拖航阻力的影响

舰船科学技术 2024年第5期46卷 59-64页

作者：许建龙刘已华李红霞黄一中国船舶集团有限公司第七〇八研究所上海200011 大连理工大学船舶工程学院辽宁大连116024

海洋核能平台2~3年需要拖航至港口进行换料,在其设计的初始阶段对平台拖航阻力的研究至关重要。考虑2种海洋核能平台概念,分析环形月池对平台拖航阻力的影响。采用STAR-CCM+软件对分离式海洋核能平台和一体式海洋核能平台在不同拖航速... 详细信息

海洋核能平台2~3年需要拖航至港口进行换料,在其设计的初始阶段对平台拖航阻力的研究至关重要。考虑2种海洋核能平台概念,分析环形月池对平台拖航阻力的影响。采用STAR-CCM+软件对分离式海洋核能平台和一体式海洋核能平台在不同拖航速度时的拖航阻力进行计算。结果表明,随着拖航速度的增大,拖航阻力增加明显;月池的存在使平台周围流场趋于紊乱,导致核能平台拖航阻力增加;对月池增阻机理的分析可为核能平台的设计提供参考。

关键词：拖航阻力环形月池计算流体动力学浮式核电平台

Extra-Large Magnetoresistance in Fe/In2O3 Granular Films

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Chinese Physics Letters 2002年第7期19卷 1004-1006页

作者： huang Bao-Xin, liu yi-hua Department of Physics and State Key Laboratory of Crystal Materials Shandong University Ji\'nan 250100

Nanogranular Fe0.35/(In2O3)0.65 films with complex magnetic structure were prepared by the rf sputtering method. An extra-large magnetoresistance up to 506% was obtained at 2.2 K, which is two orders of magnitude larger than that obtained at room temperature. This is related to the interaction with the impurities influencing the local magnetization, which is quite different from the spin-dependent tunnelling effect at room temperature. The interspacing Fe atoms dispersed in the In2O3 matrix play an important role in the transportation properties of carriers at low temperature

关键词： Indium compounds

广东省农业多功能评价及复合功能空间划分研究

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农业现代化研究 2024年第1期45卷 20-32页

作者：赖焕明吴大放杨木壮刘毅华卢奕帆吴钊骏广州大学地理科学与遥感学院广东广州510006 北京大学地表过程分析与模拟教育部重点实验室北京100871

农业功能结构性失衡、功能服务区域覆盖不均是城乡发展二元化的典型特征,农业功能空间的开发与转型是破解城乡发展二元结构、推进农业现代化的有力抓手。本文通过构建农业多功能评价体系,运用耦合协调模型和空间自相关等技术方法,分析... 详细信息

农业功能结构性失衡、功能服务区域覆盖不均是城乡发展二元化的典型特征,农业功能空间的开发与转型是破解城乡发展二元结构、推进农业现代化的有力抓手。本文通过构建农业多功能评价体系,运用耦合协调模型和空间自相关等技术方法,分析广东省农业多功能及其各功能的发展状况,划分农业复合功能空间类型,辨析农业复合功能空间的发展与转型演化过程。结果表明,2010—2020年广东省农业多功能指数呈上升趋势,发展先慢后快,向非生产性主导的农业多功能转型发展,空间格局呈向沿海地区集聚的发展态势。农业各类功能指数均有所提高,生产功能呈现以粤东、粤西为中心集聚,并向粤北地区延伸,珠三角地区低值集聚的特点;社会服务功能在区域内中等水平均衡分布;农业生态服务功能形成“粤北环海”的北部生态屏障与“圈层递增”的总体格局;休闲服务功能主要分布在珠三角区域,呈现高—高集聚和低—高集聚的特点。农业复合功能空间类型主要向生态型、休闲型复合功能空间转型,形成生产—生态服务型、生产—社会服务型、生产—休闲服务型、社会—休闲服务型、社会—生态服务型5种类型的农业复合功能空间新格局。广东省农业多功能持续融合、复合功能空间类型多元化发展,但区域间农业功能模式存在异质性。因此,本文提出应统筹规划农业功能空间的开发与转型,开发与保护并举,探索因地制宜的农业功能空间协调发展路径,以期为广东省农业功能空间格局优化、农业空间集约高效利用、城乡融合发展提供理论依据。

关键词：农业多功能复合功能功能空间划分空间格局农业现代化广东省

STATUS, CAUSES AND COMBATING SUGGESTIONS OF SANDY DESERTIFICATION IN QINGHAI-TIBET PLATEAU

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Chinese Geographical Science 2005年第4期15卷 289-296页

作者： liu yi-hua DONG Guang-rong LI Sen DONG Yu-xiang School of Geography Guangzhou University Guangzhou 510405 P. R. China Cold and A rid Regions Environment and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 P. R. China Department of Tourism and Geography Foshan University Foshan 528000 P. R. China Department of Territorial Resource and Environment SUN Yat-Sen University Guangzhou 510275 P. R. China

The Qinghai-Tibet Plateau is one of the major sandy desertification regions of China. Based on the recent investigation on sandy desertification, this paper analyses the status such as the type, area, distribution and damage of sandy land desertification in the plateau. Through the analysis on the factors affecting sandy desertification in the region’s natural and socio-economic systems as well as the processes and their interrelations, it can be concluded that sandy desertification in the Qinghai-Tibet Plateau resulted from the combined actions of normal natural sand drift processes, natural sandy desertification processes caused by climatic changes and man-made sandy desertification caused by improper human activities. In addition, it also predicts the possible developmental trend including the increase in desertification area and the enhancement in desertification developmental degree with the exacerbation of the complex processes, and finally puts forward some strategic suggestions to combat sandy desertification in the coming years.

关键词： Qinghai-Tibet Plateau sandy desertification desertification control

Giant Magneto-Impedance Effect in As-Deposited Multilayered Amorphous Films

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Chinese Physics Letters 1999年第6期16卷 452-454页

作者： XIAO Shu-qin liu De-zhen liu yi-hua DAI You-yong ZHANG Lin MEI Liang-mo Department of Physics Shandong UniversityJi'nan 250100 College of Materials Science and Engineering Shandong University of TechnologyJi'nan 250014

Giant magneto-impedance effects have been observed in as-deposited amorphous FeCuNbSiB/Cu/FeCuNbSiB and FeCuNbSiB/SiO_(2)/Ag/SiO_(2)/FeCuNbSiB multilayered *** films were deposited onto Si substrates by radio frequency *** FeCuNbSiB/Cu/FeCuNbSiB films,maximum giant magneto-impedance ratios as large as 32%and 11%were obtained at 13 MHz in the longitudinal and transverse fields,*** FeCuNbSiB/SiO_(2)/Ag/SiO_(2)/FeCuNbSiB films,the maximum giant magneto-impedance ratios were 47%and 57%at the same frequency for the two cases,which are much larger than those obtained in the annealed single layer Hlms.

关键词： impedance amorphous transverse

Part-Whole Relational Few-Shot 3D Point Cloud Semantic Segmentation

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Computers, Materials & Continua 2024年第3期78卷 3021-3039页

作者： Shoukun Xu Lujun Zhang Guangqi Jiang yining hua yi liu School of Computer Science and Artificial Intelligence Aliyun School of Big Data and School of SoftwareChangzhou UniversityChangzhou213164China Department of Computer Science University of AberdeenKing’s CollegeAberdeenAB243FXUK

This paper focuses on the task of few-shot 3D point cloud semantic *** some progress,this task still encounters many issues due to the insufficient samples given,e.g.,incomplete object segmentation and inaccurate semantic *** tackle these issues,we first leverage part-whole relationships into the task of 3D point cloud semantic segmentation to capture semantic integrity,which is empowered by the dynamic capsule routing with the module of 3D Capsule Networks(CapsNets)in the embedding ***,the dynamic routing amalgamates geometric information of the 3D point cloud data to construct higher-level feature representations,which capture the relationships between object parts and their ***,we designed a multi-prototype enhancement module to enhance the prototype ***,the single-prototype enhancement mechanism is expanded to the multi-prototype enhancement version for capturing rich ***,the shot-correlation within the category is calculated via the interaction of different samples to enhance the intra-category *** studies prove that the involved part-whole relations and proposed multi-prototype enhancement module help to achieve complete object segmentation and improve semantic ***,under the integration of these two modules,quantitative and qualitative experiments on two public benchmarks,including S3DIS and ScanNet,indicate the superior performance of the proposed framework on the task of 3D point cloud semantic segmentation,compared to some state-of-the-art methods.

关键词： Few-shot point cloud semantic segmentation CapsNets

Controllable Construction of Vinyl Sulfones and β-Keto Selenosulfones via Selective Oxidative Sulfonylation of Alkenes

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Chinese Journal of Chemistry 2024年第12期42卷 1367-1372页

作者： Xiang liu Yuan Zhang yi Zheng Changfeng huang hua Cao School of Chemistry and Chemical Engineering Guangdong Pharmaceutical UniversityZhongshanGuangdong 528458China

Comprehensive Summary The selective oxidative sulfonylation of alkenes with selenium sulfonate depended on the reaction *** electrochemical C—H sulfonylation proceeded smoothly to afford(E)-vinyl sulfones with good selectivity in an undivided cell without external *** aerobic trifunctionalization of alkenes occurred in the presence of KI in the air,which providesβ-keto selenosulfones via the formation of C—O,C—S,and C—Se bonds in *** control experiments,a plausible mechanism is proposed to rationalize the experimental results.

关键词： Synthetic methods Alkenes Difunctionalization Selenylation Sulfonylation

转录组分析调控桃采后冷害和硬度的候选主效基因

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农业生物技术学报 2024年第4期32卷 751-761页

作者：张志刚陈玉峰王长江徐晋姜延伟郑亚琴刘振宁陈守兵刘一华徐蒙临沂大学农林科学学院邹城市自然资源和规划局

冷敏性果实采后低温贮藏容易造成果实冷害，程序性降温(low-temperature conditioning, LTC)处理在减缓桃(Prunus persica)等冷敏性果实冷害中具有显著效果，但是贮藏前期果实会发生轻微软化。本研究通过加权基因共表达网络分析(weighte... 详细信息

冷敏性果实采后低温贮藏容易造成果实冷害，程序性降温(low-temperature conditioning, LTC)处理在减缓桃(Prunus persica)等冷敏性果实冷害中具有显著效果，但是贮藏前期果实会发生轻微软化。本研究通过加权基因共表达网络分析(weighted gene co-expression network analysis, WGCNA)发现了与冷害和硬度表型高度相关的基因模块。分别对模块基因进行主效转录因子鉴定和调控网络构建，发现桃WRKY转录因子PpWRKY43和生长素响应因子(auxin response factor, ARF) PpARF1可能通过调控冷调节蛋白(cold-regulated protein, COR) PpCOR413-2和脂氧合酶(lipoxygenase 5, LOX5) PpLOX5参与果实采后冷害调控，NAC转录因子PpNAC5可能通过调控桃果胶裂解酶2(P. persica pectate lyase 2, PpePL2)参与桃果实采后软化。本研究结果为桃果实采后保鲜减损研究提供基础资料。

关键词：桃采后冷害加权基因共表达网络分析(WGCNA) 硬度

Multisensory Conflict Impairs Cortico-Muscular Network Connectivity and Postural Stability: Insights from Partial Directed Coherence Analysis

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Neuroscience Bulletin 2024年第1期40卷 79-89页

作者： Guozheng Wang yi Yang Kangli Dong Anke hua Jian Wang Jun liu Key Laboratory for Biomedical Engineering of Ministry of Education College of Biomedical Engineering&Instrument ScienceZhejiang UniversityHangzhou 310058China Taizhou Key Laboratory of Medical Devices and Advanced Materials Research Institute of Zhejiang University-TaizhouTaizhou 318000China Department of Sports Science College of EducationZhejiang UniversityHangzhou 310058China Center for Psychological Science Zhejiang UniversityHangzhou 310058China

Sensory conflict impacts postural control,yet its effect on cortico-muscular interaction remains *** aimed to investigate sensory conflict's influence on the cortico-muscular network and postural *** used a rotating platform and virtual reality to present subjects with congruent and incongruent sensory input,recorded EEG(electroencephalogram)and EMG(electromyogram)data,and constructed a directed connectivity *** results suggest that,compared to sensory congruence,during sensory conflict:(1)connectivity among the sensorimotor,visual,and posterior parietal cortex generally decreases,(2)cortical control over the muscles is weakened,(3)feedback from muscles to the cortex is strengthened,and(4)the range of body sway increases and its complexity *** results underline the intricate effects of sensory conflict on cortico-muscular *** the sensory conflict,the brain adaptively decreases the integration of conflicting *** this integrated information,cortical control over muscles may be lessened,whereas the muscle feedback may be enhanced in compensation.

关键词： Cortico-muscular interaction Postural control Virtual reality Electroencephalogram Electromyography Sensory integration