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Modeling and Verification of an Astronaut Handling Large-mass Payload

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Chinese Journal of Mechanical Engineering 2010年第4期23卷 517-523页

作者： yang aiping yang Chunxin KE Peng School of Aeronautics Science and Engineering Beihang University Beijing 100191 China School of Transportation Science andEngineering Beihang University Beijing 100191 China

The experiments on astronaut motions are difficult to conduct due to the limitation and high cost of constructing or simulating the microgravity environment of space. Therefore, the method of computer simulation on astronaut extravehicular activity is broadly promoted. However, validations and verifications for these simulations stated in related literatures are incomplete such as comparing with the limits of human body movements or reconstructing a three-dimensional movement for some parts of EVA video. Novel modeling and verification methods for the task of an astronaut handling targe-mass payload during EVA were revealed. A simplified model of an astronaut was constructed, and the astronaut motion was conceived as a planar movement of a multi-body system which includes seven segments with six revolute joints in the human body sagittal plane. The inverse kinematics method was used to calculate joint angles, joint velocities, and joint accelerations in time domain. The solution of joint torques using the inverse recursive dynamics was achieved. Furthermore, a virtual model with the ADAMSTM software was developed and implemented to verify the results by adding the kinematical data calculated to joints in order to achieve the trace of the center of mass of the hand. Additionally, the joints kinematics and kinetics data with time in the virtual model were obtained and compared with the corresponding calculated data. This result indicates that the modeling methods proposed can be employed as a solid algorithm to conduct the simulation of astronaut＇s tasks in EVA, and verification using the virtual model can be easily operated and has a good accuracy. This study provides an effective and economical way of modeling and simulation for extravehicular missions.

关键词： extravehicular activity inverse kinematics inverse recursive dynamics ADAIVISTM virtual model

粤港澳居民“互嵌式社区”如何实现党建引领治理?——基于粤港澳大湾区A地社区的观察

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深圳社会科学 2025年第1期8卷 36-46页

作者：杨爱平黄天华南师范大学政治与公共管理学院广东广州510006

近年来,在支持港澳更好融入国家发展大局的政策环境下,粤港澳大湾区深圳、珠海、广州、中山等内地城市涌现出一批粤港澳居民共居共处的互嵌式社区。党建引领粤港澳居民互嵌式社区治理作为一个“新生事物”,既对地方党建部门创新大湾区... 详细信息

近年来,在支持港澳更好融入国家发展大局的政策环境下,粤港澳大湾区深圳、珠海、广州、中山等内地城市涌现出一批粤港澳居民共居共处的互嵌式社区。党建引领粤港澳居民互嵌式社区治理作为一个“新生事物”,既对地方党建部门创新大湾区融合发展下的党建工作具有现实意义,也对拓展社会主义主体制度下传统党建研究具有重要的理论价值。基于对粤港澳大湾区A地社区的调查,构建了“三重情境—四动过程”的分析框架,并透过“情境”与“过程”的双维画像,对党建引领粤港澳居民互嵌式社区治理的生成机理与实践路径进行探讨。研究发现:党建引领社区治理的生成机理蕴含了粤港澳大湾区融合发展的特殊元素,可从“在哪引领”的空间场域、“由谁引领”的行动主体、“为谁引领”的服务对象这“三重情境”加以透视;实践路径则映射于由表及里、循序渐进的“形动党建→行动党建→心动党建→传动党建”这“四动过程”中。未来应由基层党组织作为“龙头”行动主体,同时锚定互嵌式社区中的粤港澳居民服务对象,通过由表及里、循序渐进的党建引领路径,促进粤港澳三地居民融合,最终激发大湾区融合发展下党建引领互嵌式社区治理的工作效能。

关键词：党建引领社区治理粤港澳居民互嵌式社区粤港澳大湾区融合

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Diagenesis and porosity evolution of sandstone reservoirs in the East II part of Sulige gas field, Ordos Basin

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International Journal of Mining Science and Technology 2012年第3期22卷 311-316页

作者： yang Renchao Fan aiping Han Zuozhen Wang Xiuping Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Minerals College of Geological Sciences and EngineeringShandong University of Science and Technology Qingdao 266510 China

It is becoming an important controlling factor of gas exploration and exploitation in the east part of Sulige gas field in the Ordos Basin where the reservoir of main gas formations is tight sandstones. Employing experimental methods of slice identification, casting slice, scan electron microscope, and X-ray diffrac- tions, we studied the characteristics of petrology and diagenesis on reservoirs in Shanl section of Shanxi formation and He8 section of Shihezi formation of the Permian system in the East II part of Sulige gas field. The results include：（1） the main sandstones in these areas are dominated by lithic sandstone and litbic silicarenite with low grade of maturity; （2） the diagenesis of sandstone in these areas mainly include compaction, cementation, corrosion and alteration. Conclusions are as follows：（1） the diagenetic stage reached period B of the middle diagenetic stage; （2） the early diagenetic compaction is one of the main factors to decreasing porosity; （3） the secondary pores formed by corrosion in acidity medium con- ditions in period A of the middle diagenetic stage can distinctly ameliorate the poor reservoir capability of sandstone and, （4） cementation in period B of the middle diagenetic stage is the most important factor leading; to poor physical property of sandstone reservoirs.

关键词： Ordos BasinPermianSandstone reservoirsDiagenesisPorosity evolution

Measuring the magnetic topological spin structure of light using an anapole probe

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Light(Science & Applications) 2022年第10期11卷 2503-2511页

作者： Fanfei Meng aiping yang Kang Du Fengyang Jia Xinrui Lei Ting Mei Luping Du Xiaocong Yuan Nanophotonics Research Centre Institute of Microscale OptoelectronicsShenzhen University518060 ShenzhenChina MOE Key Laboratory of Material Physics and Chemistry under Extraordinary Conditions and Shaanxi Key Laboratory of Optical Information Technology School of Physical Science and TechnologyNorthwestern Polytechnical University710129 Xi'anChina

Topological spin structures of light,including the Skyrmion,Meron,and bi-Meron,are intriguing optical phenomena that arise from spin-orbit *** have promising potential applications in nano-metrology,data storage,super-resolved imaging and chiral *** from the electric part of optical spin,of equal importance is the magnetic part,particularly the H-type electromagnetic modes for which the spin topological properties of the field are dominated by the magnetic ***,their observation and measurement remains absent and faces difficult ***,we design a unique type of anapole probe to measure specifically the photonic spin structures dominated by magnetic *** probe is composed of an Ag-core and Si-shell nanosphere,which manifests as a pure magnetic dipole with no electric *** effectiveness of the method was validated by characterizing the magnetic field distributions of various focused vector *** was subsequently employed to measure the magnetic topological spin structures,including individual Skyrmions and Meron/Skyrmion lattices for the first *** proposed method may be a powerful tool to characterize the magnetic properties of optical spin and valuable in advancing spin photonics.

关键词： field. topological dipole

RPNet: Rice plant counting after tillering stage based on plant attention and multiple supervision network

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The Crop Journal 2023年第5期11卷 1586-1594页

作者： Xiaodong Bai Susong Gu Pichao Liu aiping yang Zhe Cai Jianjun Wang Jianguo Yao School of Computer Science and Technology Hainan UniversityHaikou 570228HainanChina Institute of Advanced Technology Nanjing University of Posts and TelecommunicationsNanjing 210003JiangsuChina Agricultural Meteorological Center Jiangxi Meteorological BureauNanchang 330045JiangxiChina

Rice is a major food crop and is planted worldwide. Climatic deterioration, population growth, farmland shrinkage, and other factors have necessitated the application of cutting-edge technology to achieve accurate and efficient rice production. In this study, we mainly focus on the precise counting of rice plants in paddy field and design a novel deep learning network, RPNet, consisting of four modules: feature encoder, attention block, initial density map generator, and attention map generator. Additionally, we propose a novel loss function called RPloss. This loss function considers the magnitude relationship between different sub-loss functions and ensures the validity of the designed network. To verify the proposed method, we conducted experiments on our recently presented URC dataset, which is an unmanned aerial vehicle dataset that is quite challenged at counting rice plants. For experimental comparison, we chose some popular or recently proposed counting methods, namely MCNN, CSRNet, SANet, TasselNetV2, and FIDTM. In the experiment, the mean absolute error(MAE), root mean squared error(RMSE), relative MAE(rMAE) and relative RMSE(rRMSE) of the proposed RPNet were 8.3, 11.2, 1.2% and 1.6%, respectively,for the URC dataset. RPNet surpasses state-of-the-art methods in plant counting. To verify the universality of the proposed method, we conducted experiments on the well-know MTC and WED datasets. The final results on these datasets showed that our network achieved the best results compared with excellent previous approaches. The experiments showed that the proposed RPNet can be utilized to count rice plants in paddy fields and replace traditional methods.

关键词： Rice Precision agriculture Plant counting Deep learning Attention mechanism

Rice Plant Counting,Locating,and Sizing Method Based on High-Throughput UAV RGB Images

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Plant Phenomics 2023年第2期5卷 123-138页

作者： Xiaodong Bai Pichao Liu Zhiguo Cao Hao Lu Haipeng Xiong aiping yang Zhe Cai Jianjun Wang Jianguo Yao School of Computer Science and Technology Hainan UniversityHaikou 570228China School of Telecommunication and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhan 430074China School of Computing National University of SingaporeSingapore 119077Singapore Agricultural Meteorological Center Jiangxi Meteorological BureauNanchang 330045China

Rice plant counting is crucial for many applications in rice production,such as yield estimation,growth diagnosis,disaster loss assessment,***,rice counting still heavily relies on tedious and time-consuming manual *** alleviate the workload of rice counting,we employed an UAV(unmanned aerial vehicle)to collect the RGB images of the paddy ***,we proposed a new rice plant counting,locating,and sizing method(RiceNet),which consists of one feature extractor frontend and 3 feature decoder modules,namely,density map estimator,plant location detector,and plant size *** RiceNet,rice plant attention mechanism and positive–negative loss are designed to improve the ability to distinguish plants from background and the quality of the estimated density *** verify the validity of our method,we propose a new UAV-based rice counting dataset,which contains 355 images and 257,793 manual labeled *** results show that the mean absolute error and root mean square error of the proposed RiceNet are 8.6 and 11.2,***,we validated the performance of our method with two other popular crop *** these three datasets,our method significantly outperforms state-of-the-art *** suggest that RiceNet can accurately and efficiently estimate the number of rice plants and replace the traditional manual method.

关键词： paddy disaster Plant

7,8-DHF对糖尿病大鼠视网膜的保护作用及其机制

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眼科新进展 2025年第1期45卷 5-9页

作者：杨爱萍郑新宝陈春峰陈佳玉夏静李明芳吴陆赟赵永旺上海交通大学医学院附属松江医院上海市201600

目的探讨7,8-二羟基黄酮(7,8-DHF)对糖尿病大鼠视网膜的保护作用及其机制。方法取SPF级雄性SD大鼠18只,将大鼠随机分为正常组、模型组和实验组,每组6只。正常组采用普通饲料喂养,其余大鼠采用高脂乳剂连续灌胃2周建立糖尿病模型。实验... 详细信息

目的探讨7,8-二羟基黄酮(7,8-DHF)对糖尿病大鼠视网膜的保护作用及其机制。方法取SPF级雄性SD大鼠18只,将大鼠随机分为正常组、模型组和实验组,每组6只。正常组采用普通饲料喂养,其余大鼠采用高脂乳剂连续灌胃2周建立糖尿病模型。实验组大鼠给予7,8-DHF(5 mg·kg^(-1))腹腔注射干预,正常组和模型组大鼠给予同等量生理盐水,各组大鼠每天干预1次,连续2周。观察各组大鼠造模前后体重与空腹血糖变化。2周后采用眼底照相和眼底荧光素血管造影(FFA)观察各组大鼠眼底视网膜变化。采用HE染色、CD31免疫荧光及TUNEL实验检测大鼠视网膜神经细胞变化及凋亡情况。结果干预2周后,与正常组相比,模型组和实验组大鼠体重均下降,空腹血糖均上升,差异均有统计学意义(均为P0.05)。TUNEL实验结果显示,与正常组比较,模型组大鼠视网膜神经凋亡细胞数明显增加,差异有统计学意义(P<0.001);与模型组相比,实验组大鼠视网膜神经凋亡细胞数明显减少,差异有统计学意义(P<0.001)。结论糖尿病大鼠视网膜神经凋亡可能早于血管内皮细胞损伤。7,8-DHF可以改善糖尿病大鼠体重及降低血糖,保护DM大鼠视网膜神经细胞。

关键词： 7,8-二羟基黄酮糖尿病大鼠视网膜神经细胞凋亡

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粤港澳大湾区跨境治理中的包容性府际关系

学术研究 2022年第10期 59-66页

作者：杨爱平华南师范大学政治与公共管理学院广东广州510006

港澳回归以来,“一国两制”下的粤港澳跨境治理历经了传统的粤港澳合作和当下的大湾区建设两个阶段,由此衍生了不同的府际关系生态。过往研究多把粤港澳府际关系概称为府际竞合关系和非对称性关系,已无法解释大湾区建设战略下粤港澳府... 详细信息

港澳回归以来,“一国两制”下的粤港澳跨境治理历经了传统的粤港澳合作和当下的大湾区建设两个阶段,由此衍生了不同的府际关系生态。过往研究多把粤港澳府际关系概称为府际竞合关系和非对称性关系,已无法解释大湾区建设战略下粤港澳府际关系的历史嬗变。在港澳融入国家发展大局背景下,粤港澳大湾区跨境治理正孕育生成新型的包容性府际关系。它表现为七种结构样态,具有目标诉求趋同、权力地位对等、行动协调联动、利益让渡共享的四大特质。就长远而言,包容性府际关系可否由渐进发展的态势稳固为良性运转的定势,是保障粤港澳大湾区建设行稳致远的关键。这需要中央和粤港澳三地政府综合运用授权、放权、赋权(能)、让权(利)、扩权(增能)等机制,对央地关系、港澳特别行政区内部的三权关系,以及港澳特别行政区政府的角色与职能,进行适应性调整和重塑。

关键词：融入国家发展大局粤港澳大湾区跨境治理非对称府际关系包容性府际关系

粤港澳大湾区世界级城市群治理体系创新的路径选择

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华南师范大学学报（社会科学版） 2021年第6期 15-25,205页

作者：杨爱平华南师范大学政治与公共管理学院广州510006

以体制机制为核心的大湾区治理体系创新,关乎粤港澳大湾区世界级城市群建设的治理效能,具有重要的理论和现实意义。“一国两制”下粤港澳大湾区城市群是一个跨境和跨制度治理的城市群,因而需要既借鉴吸收国际经验又兼顾中国国情和粤港... 详细信息

以体制机制为核心的大湾区治理体系创新,关乎粤港澳大湾区世界级城市群建设的治理效能,具有重要的理论和现实意义。“一国两制”下粤港澳大湾区城市群是一个跨境和跨制度治理的城市群,因而需要既借鉴吸收国际经验又兼顾中国国情和粤港澳区域治理的特殊情境,来审视谋划其治理体系创新。根据新时代中国国家治理体系的“价值、结构与功能”三维一体的分析框架,建议粤港澳大湾区世界级城市群治理体系创新选择“三横四纵”的路径:秉持稳定、高效、开放、共享四大价值理念,指导大湾区城市群治理体系创新实践;通过治理结构的改革,创新国家统合治理的体制、行政协调治理的机制、市场一体化治理的模式和社会融入治理的政策;最终达致政治上稳定有序、行政上高效协调、市场上开放发达、社会上协作共享的功能调适,构建起粤港澳大湾区城市群命运共同体。

关键词：粤港澳大湾区跨制度治理世界级城市群治理体系三横四纵框架