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太行山小流域特大暴雨洪水关系及过程研究

水土保持学报 2003年第6期17卷 102-105页

作者：曹建生张万军唐常源中国科学院石家庄农业现代化研究所河北石家庄050021 千叶大学

分析发生在2000年7月3～6日,历时72h,暴雨总量达358.1.mm特大暴雨特征的基础上,通过对小流域出口断面流量的连续监测,进一步分析了暴雨洪水关系及演变过程。结果发现:此次暴雨属于局部性、历时长、中心强度大的特大型暴雨,暴雨强度的峰... 详细信息

分析发生在2000年7月3～6日,历时72h,暴雨总量达358.1.mm特大暴雨特征的基础上,通过对小流域出口断面流量的连续监测,进一步分析了暴雨洪水关系及演变过程。结果发现:此次暴雨属于局部性、历时长、中心强度大的特大型暴雨,暴雨强度的峰值达到了32.84mm/h,出现在降雨过程的后期;暴雨洪水在出口断面上的响应出现在降雨过程的中后期,且后期尤为明显,另外由于流域面积较小,汇流时间短,响应到来的时间也较短。同时,经过进一步分析和计算得出,此次降雨过程的最大洪峰流量为1.1.5m^3/s,最大洪峰流量的径流模数为3.66m^3/(s·km^2),时段最大暴雨径流系数为0.567;整个降雨历时内所产生的洪水总量为33030.54m^3,平均径流系数为0.304。

关键词：特大暴雨暴雨洪水关系特征分析

Numerical analysis of a projecting wall type oscillating water column(PW-OWC)wave energy converter in regular waves

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Journal of Hydrodynamics 2024年第3期36卷 479-491页

作者： Lei Tan Ruiyuan chang Tomoki Ikoma Department of Oceanic Architecture and Engineering College of Science and TechnologyNihon UniversityChibaJapan

Oscillating water column(OWC)based wave energy absorption devices are classic which have been widely used for harnessing ocean wave *** paper presents a numerical study on a projecting wall(PW)type OWC wave energy converter in regular *** computational fluid dynamics(CFD)modelling of a stationary floating PW-OWC model in a three-dimensional wave flume is achieved by the software *** analyses are carried out based on CFD simulations and the linear potential flow solutions with modifications to account for turbine-induced *** present numerical solutions are validated against our previous experimental *** is found that both the CFD and modified linear potential flow predictions are in reasonably good agreements with the experimental data in the first order results of OWC and air pressure *** the nonlinear responses are included in the result,the modified linear potential flow solution is found to slightly under-estimate the wave energy conversion performance at long *** the airflows above and below the chamber orifice,the CFD results suggest that they are almost unidirectional,oscillating in not only the base frequency but also subharmonic and ultraharmonic *** evolution of the OWC responses during an entire period and the phase analysis based on CFD simulations are *** phase results provide the crucial evidence to the reasonability of the physics-based modification of the potential flow model in modelling of *** present results and analysis are expected to be beneficial to the understanding on the physical mechanism of OWCs and the design of phase control strategies.

关键词： Computational fluid dynamics(CFD)simulation hydrodynamic analysis oscillating water column(OWC)damping orifice airflow phase difference

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栽培草莓品种果实香气特性研究

分析测试学报 2004年第2期23卷 56-60页

作者：姜远茂彭福田刘松忠束怀瑞李可昌山东农业大学园艺学院山东泰安271018 中科院广州地球化学研究所有机分析中心广东广州510640

通过对4个不同栽培草莓 (FragariaananassaDuch.)品种果实糖和氨基酸测定及香气的GC -MS分析 ,结果表明 :不同品种间氨基酸和糖含量不同 ,氨基酸含量由高到低依次为丰香、瓦尔达、哈达和全明星 ;哈达、丰香、全明星和瓦尔达4个品种果实... 详细信息

通过对4个不同栽培草莓 (FragariaananassaDuch.)品种果实糖和氨基酸测定及香气的GC -MS分析 ,结果表明 :不同品种间氨基酸和糖含量不同 ,氨基酸含量由高到低依次为丰香、瓦尔达、哈达和全明星 ;哈达、丰香、全明星和瓦尔达4个品种果实分别检测出39、46、37和44种香气成分 ,各占总峰面积98.52 %、99.1. %、98.77 %和95.41.% ,检测成分的多少与氨基酸总量显著正相关 ,相关系数为0.967 ;哈达有5种独有的成分 ,丰香有9种独有的成分 ,全明星有3种独有的成分 ,瓦尔达有2种独有的成分 ,4个品种共有的成分有1.种。

关键词：草莓品种果实香气成分糖氨基酸含量测定气相色谱-质谱

An Experimental Study on Response and Control of a Flapping-Wing Aerial Robot Under Wind Gusts

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Journal of Bionic Engineering 2024年第1期21卷 209-223页

作者： Kazuki Shimura Hikaru Aono chang-kwon Kang Graduate School of Science and Technology Shinshu University3-15-1 TokidaUedaNagano 3868567Japan Department of Mechanical Engineering and Robotics 3-15-1 TokidaUedaNagano 3868567Japan Department of Mechanical and Aerospace Engineering University of Alabama in HuntsvilleTechnology Hall N266HuntsvilleAL35899USA

Bioinspired flapping-wing micro-air-vehicles(FWMAVs)have the potential to be useful aerial tools for gathering information in various *** recent advancements in manufacturing technologies and better understanding of aerodynamic mechanisms behind of the flapping flight,outdoor flights have become a ***,to fully realize the potential of FWMAVs,further improvements are necessary,particularly in terms of stability and robustness under gusty *** this study,the response and control of a tailless two-winged FWMAV under the wind gusts are *** experiments are conducted with a one-degree-of-freedom gimbal to focus on effects of wind gusts on the rotational motion of the ***-derivative and sliding-mode controls are adopted for the attitude *** present that the body angles changed in time and reached approximately 50°at the maximum due to the wing *** sliding-mode controller can more effectively control the rotational angle in the presence of disturbances and both the wing speed and changes in wind speed have an impact on the effectiveness of attitude *** results contribute to the development of of tailless two-winged,single-motor driven FWMAVs in terms of the design of attitude controller and testing apparatus.

关键词： Flapping-wing micro-air vehicles Sliding-mode control Pitch and roll angle-Wind gus

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三角法光学非接触测量头应用中的关键技术

天津大学学报（自然科学与工程技术版） 2005年第1期38卷 69-73页

作者：吴奎先杨仁平张国雄李敬杰裘祖荣于复生冷长林中国工程物理研究院化工材料研究所绵阳621900 天津大学精密测试技术及仪器国家重点实验室天津300072

光学非接触测头在其实际应用中,有一系列问题需要解决.为此,对三角法测量头的灵敏度与特性标定、工件的倾斜与颜色的影响、光束功率与引起的温升、测头的位置找正、测头系统的作用半径标定等应用中的关键技术进行了实验研究,提出了误差... 详细信息

光学非接触测头在其实际应用中,有一系列问题需要解决.为此,对三角法测量头的灵敏度与特性标定、工件的倾斜与颜色的影响、光束功率与引起的温升、测头的位置找正、测头系统的作用半径标定等应用中的关键技术进行了实验研究,提出了误差补偿、提高调整和标定精度以提高光学非接触测头使用精度的方法.

关键词：测量非接触测头三角法标定作用半径

Cell replacement with stem cell-derived retinal ganglion cells from different protocols

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Neural Regeneration Research 2024年第4期19卷 807-810页

作者： Ziming Luo Kun-Che chang Spencer Center for Vision Research Byers Eye InstituteStanford University School of Medicine Department of Ophthalmology Louis J.Fox Center for Vision RestorationUniversity of Pittsburgh School of Medicine Department of Neurobiology Center of NeuroscienceUniversity of Pittsburgh School of Medicine

Glaucoma,characterized by a degenerative loss of retinal ganglion cells,is the second leading cause of blindness *** is currently no cure for vision loss in glaucoma because retinal ganglion cells do not regenerate and are not replaced after *** stem cell-derived retinal ganglion cell transplant is a potential therapeutic strategy for retinal ganglion cell degenerative *** this review,we first discuss a 2D protocol for retinal ganglion cell differentiation from human stem cell culture,including a rapid protocol that can generate retinal ganglion cells in less than two weeks and focus on their transplantation ***,we discuss using 3D retinal organoids for retinal ganglion cell transplantation,comparing cell suspensions and *** review provides insight into current knowledge on human stem cell-derived retinal ganglion cell differentiation and transplantation,with an impact on the field of regenerative medicine and especially retinal ganglion cell degenerative diseases such as glaucoma and other optic neuropathies.

关键词： cell clumps cell suspension cell transplantation differentiation direct-induced protocol glaucoma optic neuropathy regenerative medicine retinal ganglion cell retinal organoids stem cells

Designing a Secure and Scalable Data Sharing Mechanism Using Decentralized Identifiers(DID)

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Computer Modeling in Engineering & Sciences 2024年第10期141卷 809-822页

作者： Iuon-chang Lin I-Ling Yeh Ching-Chun chang Jui-Chuan Liu Chin-Chen chang Department of Management Information Systems National Chung Hsing UniversityTaichung402Taiwan Information and Communication Security Research Center Feng Chia UniversityTaichung407Taiwan Department of Information Engineering and Computer Science Feng Chia UniversityTaichung407Taiwan

Centralized storage and identity identification methods pose many risks,including hacker attacks,data misuse,and single points of ***,existing centralized identity management methods face interoperability issues and rely on a single identity provider,leaving users without control over their ***,this paper proposes a mechanism for identity identification and data sharing based on decentralized *** scheme utilizes blockchain technology to store the identifiers and data hashed on the chain to ensure permanent identity recognition and data *** is stored on InterPlanetary File System(IPFS)to avoid the risk of single points of failure and to enhance data persistence and *** the same time,compliance with World Wide Web Consortium(W3C)standards for decentralized identifiers and verifiable credentials increases the mechanism’s scalability and interoperability.

关键词： Self-sovereign identity decentralized identifier blockchain

Confluence of asymmetric catalysis and electrosynthesis in sustainable chemical transformations

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Science China Chemistry 2024年第3期67卷 755-758页

作者： Qinglin Zhang Kang Liang chang Guo Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry University of Science and Technology of ChinaHefei 230026China

Electrosynthesis has gained widespread recognition for its extraordinary ability to precisely control the redox *** outstanding capability enables the direct conversion of non-functionalized substrates into reactive intermediates by utilizing easily accessible starting materials, eliminating the need for preliminary functionalization procedures and allowing for unconventional bond activations.

关键词： Confluence of asymmetric catalysis and electrosynthesis in sustainable chemical transformations

Spin-orbit interaction induced Casimir-Lifshitz torque between two-dimensional electron gases

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 134-142页

作者： Jia-Nan Rong Liang Chen Kai chang State Key Laboratory of Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China School of Mathematics and Physics North China Electric Power UniversityBeijing 102206China School of Physics Zhejiang UniversityHangzhou 310027China College of Materials Science and Opto-electronic Technology University of Chinese Academy of SciencesBeijing 100049China

We investigate theoretically the Casimir interaction between two parallel two-dimensional electron gases(2DEGs)with Rashba and Dresselhaus spin-orbit interactions(SOIs),based on the quantum field *** derive an analytical expression for the polarization tensor and obtain the solution to the motion equation of the electromagnetic(EM)*** calculate the CasimirLifshitz torque(CLT)between two parallel 2DEGs with Rashba and Dresselhaus SOIs,which can be tuned by changing the relative strength between two *** anisotropic Casimir energy between 2DEGs caused by the interplay between the SOIs of 2DEGs offers a new origin of CLT and a new type of optoelectronic device.

关键词： Casimir torque two-dimensional electron gas spin-orbit interaction