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基于GPM数据的辽东半岛地区降雨侵蚀力提取

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水利技术监督 2025年第1期 50-51,55页

作者：姚利刚凤城市水利事务服务中心辽宁凤城118100

降雨侵蚀力(R因子)是水土流失模型中反映降雨侵蚀动力的关键参数,对评估流失风险至关重要。文章基于新一代GPM卫星的高精度IMERG降水产品,结合随机森林回归算法预测生成辽东半岛100m分辨率的R因子分布图。结果显示:辽东半岛R因子分布范... 详细信息

降雨侵蚀力(R因子)是水土流失模型中反映降雨侵蚀动力的关键参数,对评估流失风险至关重要。文章基于新一代GPM卫星的高精度IMERG降水产品,结合随机森林回归算法预测生成辽东半岛100m分辨率的R因子分布图。结果显示:辽东半岛R因子分布范围介于之间2876~5032(MJ·mm/(hm^(2)·h·a)),呈现自北向南减少的地带性特征。地面站点独立验证显示,该R因子分布图的预测精度R2达0.69,RMSE为598.8(MJ·mm/(hm^(2)·h·a))。该研究挖掘了卫星降水资料的可用性,证实了GPM IMERG数据在大尺度地区R因子空间分布预测中具有一定潜在价值。

关键词： GPMIMERG卫星数据随机森林降雨侵蚀力辽东半岛

First-Principles Study of Phase Stability and Mechanical Property of Co_3(Al,W) Precipitates with Different Ratio of Al to W in Co Base Alloys

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稀有金属材料与工程 2009年第A3期38卷 1-4页

作者： yao Q Su X M yan y Zhao L W Sun J Shanghai Jiaotong University Shanghai 200240 China

The energetics, electronic structure and mechanical property of Co3(Al,W) precipitates with different ratio of Al to W in Co base alloys were investigated by the method of supercell and augmented plane waves plus local orbitals within generalized gradient approximation. The calculated results show that the L12 Co3(Al,W) precipitate is the most stable when the ratio of Al to W is equal to 1. When the content of W is higher than 18.5 at%, the L12 and hexagonal structures co-exist in Co3(Al,W) precipitates at 1173 K. It is also shown that the L12 ordered Co3(Al,W) precipitates have an obvious strengthening effect in the disordered fcc cobalt matrix.

关键词：铝电子结构力学性能碳酸

Molecular dynamics simulation and continuum modelling of granular surface flow in rotating drums

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Chinese Science Bulletin 2007年第5期52卷 692-700页

作者： LI ShuiQing yao Qiang CHEN Bing ZHANG Xuan DING y L Department of Thermal Engineering Tsinghua University Beijing 100084 China Department of Chemical Engineering University of Leeds Leeds LS29JT UK

Numerical simulations of granular flows in rotating drums operated at medium to high rates (Fr=0.1― 0.2) have been carried out by using a Molecular Dynamics (MD) algorithm that incorporates inelastic particle interactions, sliding friction and rolling friction. The results indicate that the behavior of granular flow in rotating drums can be classified into two distinct zones: a shear active layer at the bed surface and a quasi-static plug flow region adjacent to the wall. The residence time of a tracer particle in the active layer is approximately a third or a half of that in the plug flow region. The thickness of the active layer at mid-chord is about 0.57―0.61 times that of the plug flow region. It is found that all cases simulated in this work are in the rolling-cascading intermediate regime instead of the pure rolling re-gime. The simulated tangential velocity at the mid-chord is also compared with experimental results reported in the literature and good agreement has been obtained. Based on the MD simulations and experimental results, a continuum approach has also been developed. It is shown that the behavior of granular solids in the plug flow region experiences plastic deformation along the radial direction from the wall with the velocity profiles well described by an exponential function, whereas the active layer velocity follows a simple expression for the Couette shear flow. Discussion has also been made on the granular temperature and concentration profiles.

关键词：粒料颗粒表面流分子动力学模拟连续模型转鼓

Structural Origins for Enhanced Thermal Stability and Glass‑Forming Ability of Co–B Metallic Glasses with y and Nb Addition

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Acta Metallurgica Sinica(English Letters) 2023年第6期36卷 962-972页

作者： Shuang Ma Junyu Zhang Xudong Wang Rie y.Umetsu Li Jiang Wei Zhang Man yao Key Laboratory of Materials Modification by Laser Ionand Electron Beams(Ministry of Education)School of Materials Science and EngineeringDalian University of TechnologyDalian 116024China Institute for Materials Research Tohoku UniversitySendai 980‑8577Japan

The effects of y and Nb addition on thermal stability,glass-forming ability(GFA),and magnetic softness of Co75B25 metallic glass(MG)were comprehensively *** experimental results indicated that the thermal stability,GFA,and magnetic softness of the studied MGs increase in the order Co_(75)B_(25)y_(3.5)B_(25)y_(3.5)Nb_(2)B_(25).The structural origins of the improved properties were revealed by ab initio molecular dynamics(AIMD)simulations and density functional theory(DFT)*** showed that the B-centered prism units are the primary structure-forming units of the four MGs,connect through vertex-,edge-,and face-shared(VS,ES,and FS)atoms,and Co-centered units tend to connect with Co/B-centered units via the intercross-shared(IS)*** addition of y and Nb not only plays the role of connecting atoms but also enhances both bond strengths and the fractions of icosahedral-like units in increasing order Co_(75)B_(25)y_(3.5)B_(25)y_(3.5)Nb_(2)B_(25),which is conducive to the enhancement of the structural stability,atomic packing density,and viscosity,thereby improving thermal stability and *** addition,the improvement of structural stability and homogeneity leads to enhanced magnetic softness.

关键词： Co-based metallic glasses Thermal stability Glass-forming ability Soft magnetic property Ab initio molecular dynamics simulations Local atomic structure

Metabolites of Icariin in the Gastrointestine of Rats Following Oral Administration

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Chinese Chemical Letters 1998年第10期9卷 957-959页

作者： Qiu, F Gu, MZ Tan, QS Chen, yJ Kano, y.yao, XS Shenyang Pharmaceut Univ Shenyang 110015 Peoples R China Hokkaido Coll Pharm Otaru Hokkaido Japan

Further investigation of the metabolites of orally administered icariin in rats was made. Two minor metabolites, icariside I and icariside II, were identified in gastric content, and two metabolites, icariside II and ... 详细信息

关键词： icariin icariside I icariside II icaritin metabolite

Life:Ordinary World-Speech by Lu yao at Northwest University in December 1991

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Frontiers of Literary Studies in China-Selected Publications from Chinese Universities 2022年第2期16卷 186-198页

作者： LU yao JIAO Haimin(record) 不详 Documentary Department Shaanxi Media ConvergenceXi'an 710061China

ⅠI have not done much preparation for today,since it is the end of the year and I have my hands *** the past years,I have had several opportunities to express my opinions,and I do not really have any new ***,I look forward to taking some specific questions from you to exchange our ideas,so I hope this lecture will be rewarding for you.

关键词： really since Northwest

SC-CO_(2)与工业乳化炸药破岩效应的等效试验

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工程科学学报 2025年第2期47卷 249-258页

作者：蒋楠姚颖康朱斌罗学东江汉大学省部共建精细爆破国家重点实验室武汉430056 江汉大学爆破工程湖北省重点实验室武汉430056 中国地质大学(武汉)工程学院武汉430074

如何定量化核算SC-CO_(2)(超临界二氧化碳)破岩效率是非炸药类破岩技术在实际工程应用时重点关注的内容.本研究基于爆破当量理论计算和现场爆破试验的研究方法,通过工程类比法进行工业乳化炸药等效当量计算,选择典型代表性花岗岩及泥岩... 详细信息

如何定量化核算SC-CO_(2)(超临界二氧化碳)破岩效率是非炸药类破岩技术在实际工程应用时重点关注的内容.本研究基于爆破当量理论计算和现场爆破试验的研究方法,通过工程类比法进行工业乳化炸药等效当量计算,选择典型代表性花岗岩及泥岩场地,设计进行了SC-CO_(2)与工业炸药破岩效应等效对比现场试验;基于现场破岩等效现场试验测试数据,对比分析试验过程中SC-CO_(2)与工业炸药破岩体积、破岩区域形态、大块率和单耗等破岩区域特征及参量数据.研究结果表明:当SC-CO_(2)破岩体积较大时,其致裂破岩范围的长短轴较长,并且随着剪切片厚度的增加,泥岩场地二氧化碳单耗的下降速率增大,二氧化碳单耗是炸药单耗的6~11倍.SC-CO_(2)破岩技术大块率较高,而炸药爆炸应力波分布均匀,大块率较小.SC-CO_(2)破岩地表振速远小于工业炸药破岩,工业炸药爆破测点合振速值为SC-CO_(2)破岩测点合振速值的9~11倍,SC-CO_(2)破岩对周边环境震动影响较小.SC-CO_(2)破岩测点合应力峰值高于工业炸药破岩,SC-CO_(2)破岩试验中各测点合应力值为炸药破岩试验中对应测点值的1.2~1.6倍.

关键词： SC-CO_(2) 工业炸药等效破岩动力效应破岩体积

Robust Control for Static Loading of Electro-hydraulic Load Simulator with Friction Compensation

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Chinese Journal of Aeronautics 2012年第6期25卷 954-962页

作者： yao Jianyong JIAO Zongxia yao Bin School of Mechanical Engineering Nanjing University of Science and Technology Nanjing 210094 China Science and Technology on Aircraft Control Laboratory Beihang University Beijing 100191 China School of Mechanical Engineering Purdue University West Lafayette IN 47907 USA

Load simulator is a key test equipment for aircraft actuation systems in hardware-in-the-loop-simulation. Static loading is an essential function of the load simulator and widely used in the static/dynamic stiffness test of aircraft actuation systems. The tracking performance of the static loading is studied in this paper. Firstly, the nonlinear mathematical models of the hydraulic load simulator are derived, and the feedback linearization method is employed to construct a feed-forward controller to improve the force tracking performance. Considering the effect of the friction, a LuGre model based friction compensation is synthesized, in which the unmeasurable state is estimated by a dual state observer via a controlled learning mechanism to guarantee that the estimation is bounded. The modeling errors are attenuated by a well-designed robust controller with a control accuracy measured by a design parameter. Employing the dual state observer is to capture the different effects of the unmeasured state and hence can improve the friction compensation accuracy. The tracking performance is summarized by a derived theorem. Experimental results are also obtained to verify the high performance nature of the proposed control strategy.

关键词： electro-hydraulic load simulator robust control friction compensation feedback linearization LuGre model nonlinear control state estimation

A systematic framework to understand central bank digital currency

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Science China(Information Sciences) 2018年第3期61卷 206-213页

作者： Qian yao Institute of Digital Money of the People’s Bank of China

The ongoing research and development of digital fiat currency(DFC) have triggered attention of policy makers, regulators and the industrial and academic communities. But there is not yet a clear idea and blueprint of what DFC looks like. This paper establishes a systematic framework to analyze the essence and connotation of DFC from four dimensions: currency value, technical aspects, means of implementation and application scenarios. It is argued that DFC is a credit-based currency in terms of value, a crypto-currency from a technical perspective, an algorithm-based currency in terms of implementation and a smart currency in application scenarios. Compared with existing private digital currencies and electronic currencies, DFC will be equipped with brand new and higher qualities. The goal of Chinese DFC is to contribute to more stable value, more secure data, more powerful regulation, stronger empowerment of individuals in payment activities and smarter application. Chinese DFC should have qualities that enable it to provide better service for the public, to offer effective tools for macroeconomic control and to lay a solid foundation for Reg Tech development.

关键词： digital fiat currency credit-based currency crypto-currency algorithm-based currency smart currency central bank digital currency