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Fusion of In-Situ Soil Moisture and Land Surface Model Estimates Using Localized Ensemble Optimum Interpolation over China

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Journal of Meteorological Research 2020年第6期34卷 1335-1346页

作者： Lipeng jiaNG Chunxiang SHI Shuai SUN Xiao liang School of Geographic Sciences Nanjing University of Information Science&TechnologyNanjing 210044 National Meteorological Information Center China Meteorological AdministrationBeijing 100081

Land data assimilation(DA)is an effective method to provide high-quality spatially and temporally continuous soil moisture datasets that are crucial in weather,climate,hydrological,and agricultural ***,most existing land DA applications have used remote sensing observations,and are based on one-dimensional(1 D)analysis,which cannot be directly employed to reasonably assimilate the recently expanded in-situ soil moisture observations in *** this paper,a two-dimensional(2 D)localized ensemble-based optimum interpolation(En OI)scheme for assimilating in-situ soil moisture observations from over 2200 stations into land surface models(LSMs)is *** scheme uses historical LSM simulations as ensemble samples to provide soil moisture background error covariance,allowing the in-situ observation information to be propagated to surrounding *** is also computationally efficient because no additional ensemble simulations are needed.A set of ensemble sampling and localization length scale sensitivity experiments are *** En OI performs best for in-situ soil moisture fusion over China with an ensemble sampling of hourly soil moisture from the previous 7 days and a localization length scale of 100 *** the evaluation,simulations for in-situ soil moisture fusion are also performed from May 2016 to September *** En OI analysis is notably better than that without in-situ observation fusion,as the wet bias of 0.02 m3 m-3 is removed,the root-mean-square error(RMSE)is reduced by about 37%,and the correlation coefficient is increased by about 25%.Independent evaluation shows that the En OI analysis performs considerably better than that without fusion in terms of bias,and marginally better in terms of RMSE and correlation.

关键词： soil moisture fusion land surface model(LSM) ensemble optimum interpolation localization

一价铜催化的不对称插烯与插二烯炔丙基取代反应

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有机化学 2022年第11期42卷 3918-3920页

作者：李晖殷亮姚陈忠运城学院应用化学系山西运城044000 中国科学院上海有机化学研究所、中国科学院天然产物有机合成化学重点实验室上海200032

发展高效和高立体选择性构建含有多官能团化合物的新策略是现代有机合成化学的核心目标之一.插烯反应是一类可以构建多官能团化合物的有效方法[1].多烯醇硅醚是一种良好的可用于插烯反应的亲核试剂,其与多种亲电试剂的不对称插烯反应可... 详细信息

发展高效和高立体选择性构建含有多官能团化合物的新策略是现代有机合成化学的核心目标之一.插烯反应是一类可以构建多官能团化合物的有效方法[1].多烯醇硅醚是一种良好的可用于插烯反应的亲核试剂,其与多种亲电试剂的不对称插烯反应可直接生成含有至少三种官能团的手性化合物,因而其参与的不对称插烯反应受到合成化学家的广泛关注[1].

关键词：有机合成化学立体选择性取代反应手性化合物亲电试剂亲核试剂烯反应烯醇硅醚

Crust and Upper Mantle Density Structures beneath the Eastern Tianshan Region and Its Tectonic Implications

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Journal of Earth Science 2024年第3期35卷 828-838页

作者： Yiming Liu Chao Chen Qing liang Zhengwang Hu Hubei Subsurface Multi-Scale Imaging Key Laboratory School of Geophysics and GeomaticsChina University of GeosciencesWuhan 430074China

The deformation mechanisms of the Tianshan orogenic belt(TOB)are one of the most important unresolved issues in the collision of the Indian and Eurasian *** better understand the lithospheric deformation of the eastern Tianshan orogenic belt,we combined the S-wave tomography and gravity data to develop a three-dimensional(3D)density model of the crust and upper mantle beneath the eastern Tianshan *** show that the crust of the eastern Tianshan is mainly characterized by positive density anomalies,revealing widespread subduction-related magmatism during the *** however have also observed extensive low-density anomalies beneath the eastern Tianshan at depths deeper than~100 km,which is likely linked to a relatively hot *** most fundamental differences of the lithosphere within the eastern Tianshan occur in the uppermost *** uppermost mantle layers in the Bogda Shan and Harlik Shan are relatively *** is likely associated with an eclogite body in the uppermost *** most significant negative anomaly of the uppermost mantle is however found in the Jueluotage tectonic belt and the central Tianshan Block and is possibly associated with depleted mantle *** suggest that these differences related to compositional changes may control the strength of the lithospheric mantle and have affected the uplift of the northern and southern segments of the eastern Tianshan after the Permian.

关键词： constrained inversion gravity anomaly three-dimensional lithospheric density structure eastern Tianshan geodynamics geophysics.

Experimental investigation of laser-produced-plasma EUV source based on liquid target

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光学精密工程 2005年第5期13卷 604-607页

作者： QI Li-hong NI Qi-liang CHEN Bo Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences Changchun 130033 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China Institute of Atomic and Molecular Physics Jilin University Changch un 130026 China

A laser-produced plasma(LPP) source was built using liquid as target and a Nd:YAG laser as the irradiation laser, and the LPP source's radiation with ethanol and acetone target respectively was measured by an AXUV100 silicon photodiode combined with a McPHERSON model 247 grazing incidence monochromator of the resolution Δλ≤0.075 nm and the wavelength scanning interval 0.5 nm. Both ethanol and acetone target LPP source had EUV emission at 11～20 nm wavelength. The comparison between the spectra of the two kinds of target materials shows that all the two kinds of target source's spectra are the result of oxygen ions' transitions under current source's parameters, but the spectrum intensity from different target sources is different. The spectra intensity from the ethanol target is higher than that from the acetone target. In addition, the target liquid is forced into the vacuum chamber by the background pressure supported by the connected external high pressure gas, and the influence of the background pressure on the source's intensity is investigated.

关键词： LPP 激光等离子体亮度

Exoskeleton active assistance strategy for human muscle activation reduction during linear and circular walking

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Advances in Manufacturing 2024年第3期12卷 484-496页

作者： Wen-Tao Sheng Ke-Yao liang Hai-Bin Tang School of Intelligent Manufacturing Nanjing University of Science and TechnologyNanjing210094People’s Republic of China School of Mechatronics Engineering Harbin Institute of TechnologyHarbin150001People’s Republic of China

The exoskeleton is employed to assist humans in various domains including military missions,rehabilitation,industrial operation,and activities of daily living(ADLs).Walking is a fundamental ADL,and exoskeletons are capable of reducing the activation and metabolism of lower extremity muscles through active assistance during *** improve the performance of active assistance strategy,this article proposes a framework using an active hip ***,it correlates to an already established Bayesian-based human gait recognition algorithm,with a particular focus on linear and circular walking within industrial and ADL *** theorizing this strategy for exoskeletons,this study further reveals,in part,the activation characteristics of human hip muscles for the instruction and regulation of active assistance duration and onset *** proposed active assistance strategy provides new insights for enhancing the performance of assistive robots and facilitating human robot interaction within the context of ADLs.

关键词： Human-robot interaction Hip exoskeleton Muscle activation Walking assistance

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广义谱相关子空间拟合DOA估计原理

电子学报 2000年第1期28卷 60-63页

作者：金梁殷勤业解放军信息工程大学汪仪林西安交通大学电信学院信息工程研究所西安710049

本文提出了一种用广义谱相关信号子空间拟合进行波达方向估计的方法，该方法同时适用于宽带与窄带信号的ＤＯＡ估计，在窄带情形下还能够大大提高阵列的等效孔径．理论分析表明，目前几种主要的循环平稳ＤＯＡ估计方法（如ＳＣ－ＳＳ... 详细信息

本文提出了一种用广义谱相关信号子空间拟合进行波达方向估计的方法，该方法同时适用于宽带与窄带信号的ＤＯＡ估计，在窄带情形下还能够大大提高阵列的等效孔径．理论分析表明，目前几种主要的循环平稳ＤＯＡ估计方法（如ＳＣ－ＳＳＦ，ＣｙｃｌｉｃＭＵＳＩＣ，ＣｙｃｌｉｃＥＳＰＲＩＴ）均可看作是该方法的特例或近似．最后，仿真结果证明了该方法的有效性与一般性．

关键词：到达波方向估计广义谱信号估计

Engineering a high-barrier d-f single-molecule magnet centered with hexagonal bipyramidal Dy(Ⅲ)unit

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Science China Chemistry 2024年第10期67卷 3291-3298页

作者： Wei Deng Chan-ying Yao Yan-Cong Chen ying-Qian Zhou Shan-Nan Du Jun-liang Liu Ming-liang Tong Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education School of ChemistryInstitute of Green Chemistry and Molecular EngineeringGuangdong Basic Research Center of Excellence for Functional Molecular EngineeringSun Yat-sen UniversityGuangzhou 510006China

In the pursuit of high-performance single-molecule magnets(SMMs),incorporating intramolecular magnetic coupling emerges as a pivotal *** these,d-f SMMs have garnered significant attention due to their remarkable versatility,which lies in their ability to tune coordination environments and facilely substitute metal ***,achieving performance-centric d-f SMMs through the synergistic interplay between highly anisotropic f ions and d-f magnetic interactions remains a formidable *** mononuclear hexagonal bipyramidal(D_(6h))Dy^(Ⅲ)SMMs have been successfully isolated,the exploration of d-f SMMs featuring D_(6h)-lanthanide metal centers remains uncharted *** this study,we employed planar bipodal ligands in conjunction with“staple-like”axial phenoxide ligands to synthesize the first hexagonal bipyramidal d-f ***,this compound exhibits alternating-current magnetic susceptibilities peaking up to 68 K with an energy barrier surpassing 1,200 K,thus establishing a new benchmark within the heterometallic d-f SMM landscape inclusive of complexes with diamagnetic d metals and paramagnetic f ***,the ferromagnetic interaction at the d-f sites engenders oscillating relaxation times contingent on the magnetic field—a characteristic distinct from mononuclear *** findings shed light on a deliberate design approach for d-f SMMs,emphasizing the cooperative utilization of high-barrier lanthanide modules alongside d ions through magnetic *** synergy significantly enhances and diversifies the magnetic dynamics of these intriguing molecular systems.

关键词： single-molecule magnets magnetic coupling crystal engineering hexagonal bipyramid energy barrier

多输入多输出正弦振动试验控制系统算法研究及实现

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振动工程学报 2008年第1期21卷 62-65页

作者：朱银龙陈怀海贺旭东贾良现南京航空航天大学机电学院江苏南京210016 南京航空航天大学振动工程研究所江苏南京210016 中国直升机设计研究所江西景德镇333001

根据多输入多输出系统的解耦补偿思想,设计了多输入多输出正弦振动试验控制系统的控制方案。应用乘法输出不确定性描述了系统模型误差,对控制算法的收敛性进行了理论分析并对其进行了仿真,检验了算法的可行性。以微型计算机为核心,基于... 详细信息

根据多输入多输出系统的解耦补偿思想,设计了多输入多输出正弦振动试验控制系统的控制方案。应用乘法输出不确定性描述了系统模型误差,对控制算法的收敛性进行了理论分析并对其进行了仿真,检验了算法的可行性。以微型计算机为核心,基于VXI总线仪器,构建了试验控制系统。编写了测量与控制软件,实现了驱动信号发生、响应信号的采集和处理。在一悬臂梁上进行了两点正弦振动试验控制,结果表明,算法可以使控制点的响应信号快速、稳定地收敛于参考信号,验证了设计的多输入多输出正弦振动试验控制系统的有效性。

关键词：振动环境试验多输入多输出系统控制系统正弦振动振动控制

Cost-effectiveness Analysis of Two Therapeutic Regimens for Newly Diagnosed Smear-negative Pulmonary Tuberculosis

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Biomedical and Environmental Sciences 2018年第8期31卷 623-626页

作者： CHEN liang MEI Jin Zhou CHEN Xun Xun FENG Hui ying WANG jia Wen LI Hai Cheng XU Guang Hui XIAO Ling Wen HUANG Yi Xiang ZHOU Lin Center for Tuberculosis Control of Guangdong Province Guangzhou 510430GuangdongChina Bao'an ChronicDisease Prevent and Cure Hospital Shenzheng 518020GuangdongChina Institute for Tuberculosis Control of jiangmen Jiangmen 529000GuangdongChina Baiyun Center for Chronic Disease Control Guangzhou 510430GuangdongChina School of Public Health Sun Yet-sen UniversityGuangzhou 510080GuangdongChina

Tuberculosis （TB） has a severe effect on human health and causes a huge economic burden;.Previous studies have demonstrated that patients with smear-negative pulmonary TB accounted for approximately 60%-70% of the total pulmonary TB cases;. Therefore, it is extremely important to formulate safe, effective, and economic therapeutic regimens for patients with smear-negative pulmonary TB;.

关键词： TB