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Comparison of DEM accuracies generated from different stereo pairs over a plateau mountainous area

Journal of Mountain Science 2021年第6期18卷 1580-1590页

作者： LIU Han-hu zhao yin-jun WANG Lei LIU Yan-yan College of Earth Sciences Chengdu University of TechnologyChengdu 610059China Key Laboratory of Environment Change and Resources Use in Beibu Gulf Ministry of EducationGuangxi Teachers Education UniversityNanning 530001China

Digital elevation models(DEMs) can be quickly and conveniently generated using very high resolution(VHR) satellite stereo images. Previous studies have evaluated and compared DEM accuracy based on VHR satellite stereo pairs collected by different satellite sensors. However, few studies analyzed the accuracy of a DEM based on stereo image pairs from a satellite with the same orbit and different orbits for a region with significant topographic fluctuations in the plateau area. Referring to former studies, this paper had two objectives: to generate a digital elevation model(DEM) and evaluate its horizontal and vertical accuracy over a plateau area with high relief;and to study the mapping capability of multiorbit and multitemporal stereo pair images in the plateau mountainous region. To achieve these objectives, we collected the 2015 Worldview-2 stereo image pair and another three World View-2 images acquired in 2013, 2014, and 2015. First, the 2015 DEM was obtained using a strict physical model based on along-track stereo image pairs, and the reliability of the DEM was verified with field data. Then, the images obtained in 2013, 2014, and 2015 were combined into different-orbit stereo image pairs, DEMs were produced using rational function models, and the DEMs were verified using field data and the 2015 DEM as standards. The results showed that the relief degree has a particular influence on the DEM, and the precision of the DEM decreases as the topographic relief increases. Off-nadir angles can also influence DEM accuracy, with a larger angle corresponding to a lower DEM accuracy. The research also shows that the DEM obtained from four sets of experiments meets the accuracy requirement of a 1:5,000 digital elevation map, digital line graphic(DLG), and digital orthophoto map(DOM). Among these four groups of DEMs, the one based on the 2015 stereo pairs with the same satellite achieved the highest precision.

关键词： Remote sensing Worldview Satellite images Digital elevation model Photogrammetry

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A sub-grid scale model for Burgers turbulence based on the artificial neural network method

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Theoretical & Applied Mechanics Letters 2024年第3期14卷 162-165页

作者： Xin zhao Kaiyi yin Department of Mechanics Beijing Institute of TechnologyBeijing 100081China

The present study proposes a sub-grid scale model for the one-dimensional Burgers turbulence based on the neuralnetwork and deep learning *** filtered data of the direct numerical simulation is used to establish thetraining data set,the validation data set,and the test data *** artificial neural network(ANN)methodand Back Propagation method are employed to train parameters in the *** developed ANN is applied toconstruct the sub-grid scale model for the large eddy simulation of the Burgers turbulence in the *** proposed model well predicts the time correlation and the space correlation of the Burgers turbulence.

关键词： Artificial neural network Back propagation method Burgers turbulence Large eddy simulation Sub-grid scale model

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北京市海淀区2012-2021年《出生医学证明》管理现状分析与探索

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医学信息 2024年第3期37卷 69-72页

作者：赵银珠邹晓璇胡美娜殷延敏北京市海淀区妇幼保健院保健部

目的进一步提高辖区《出生医学证明》管理水平，探索适宜的《出生医学证明》业务管理策略。方法数据来源于北京市妇幼网络信息系统中《出生医学证明》模块，对北京市海淀区2012-2021年《出生医学证明》签发业务进行统计和分析。结果 2... 详细信息

目的进一步提高辖区《出生医学证明》管理水平，探索适宜的《出生医学证明》业务管理策略。方法数据来源于北京市妇幼网络信息系统中《出生医学证明》模块，对北京市海淀区2012-2021年《出生医学证明》签发业务进行统计和分析。结果 2012-2021年，海淀区新生儿活产数总体呈下降趋势，《出生医学证明》当年首次签发率在90%～95%;2012-2021年海淀区《出生医学证明》换发量比较，差异有统计学意义（P<0.05）;10年间补发量比较，差异有统计学意义（P<0.05）;2012-2021年海淀区《出生医学证明》废证率持续走低。结论应不断加强业务和辖区管理，大力推进信息化建设，更好地服务群众，提高群众的满意度和幸福感。

关键词：《出生医学证明》签发管理妇幼保健辖区管理

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Shortcut-based quantum gates on superconducting qubits in circuit QED

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Chinese Physics B 2021年第8期30卷 535-542页

作者： Zheng-yin zhao Run-ying Yan Zhi-Bo Feng School of Science Xuchang UniversityXuchang 461000China

Construction of optimal gate operations is significant for quantum *** an efficient scheme is proposed for performing shortcut-based quantum gates on superconducting qubits in circuit quantum electrodynamics(QED).Two four-level artificial atoms of Cooper-pair box circuits,having sufficient level anharmonicity,are placed in a common quantized field of circuit QED and are driven by individual classical *** the effect of cross resonance,one-qubit NOT gate and phase gate in a decoupled atom can be implemented using the invariant-based shortcuts to *** the assistance of cavity bus,a one-step SWAP gate can be obtained within a composite qubit-photon-qubit system by inversely engineering the classical *** further consider the gate realizations by adjusting the microwave *** the accessible decoherence rates,the shortcut-based gates have high *** present strategy could offer a promising route towards fast and robust quantum computation with superconducting circuits experimentally.

关键词： superconducting qubit circuit QED quantum gate shortcuts to adiabaticity

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Manganese catalyzed urea and polyurea synthesis using methanol as C1 source

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Chinese Chemical Letters 2023年第4期34卷 304-308页

作者： Jiaxin Guo Jun Tang Hui Xi Sheng-yin zhao Weiping Liu Key Laboratory of Science and Technology of Eco-Textile Ministry of EducationCollege of ChemistryChemical Engineering and BiotechnologyDonghua UniversityShanghai 201620China Key Laboratory of Tobacco Flavor Basic Research of CNTC Zhengzhou Tobacco Research Institute of CNTCZhengzhou 450001China

The manganese-catalyzed dehydrogenative coupling between methanol and amines for the synthesis of ureas and polyureas is described. Importantly, catalytic efficiency can be improved by the newly synthesized MACHO ligands. Furthermore, this highly atom-economical protocol demonstrates a broad substrate scope with good functional group tolerance, producing H_(2)as the sole byproduct. Mechanistic studies disclose that formamide is formed through manganese-catalyzed formylation of amine with *** dehydrogenation affords a transient isocyanate, which is attacked by another equivalent of amine to provide the final product.

关键词： Manganese Homogeneous catalysis Urea synthesis Polyurea synthesis Methanol as C1 source

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Retinal vessel diameter changes induced by transient high perfusion pressure

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International Journal of Ophthalmology(English edition) 2014年第4期7卷 602-607页

作者： yin-ying zhao Ping-Jun Chang Fang Yu Yun-E zhao School of Ophthalmology and Optometry Wenzhou Medical University Affiliated Eye Hospital Wenzhou Medical University

·AIM: To investigate the effects of transient high perfusion pressure on the retinal vessel diameter and retinal ganglion cells.·METHODS: The animals were divided into four groups according to different infusion pressure and infusion time(60 mm Hg-3min, 60 mm Hg-5min, 100 mm Hg-3min, 100 mm Hg-5min). Each group consisted of six rabbits. The left eye was used as the experimental eye and the right as a control. Retinal vascular diameters were evaluated before, during infusion, immediately after infusion, 5min, 10 min and 30 min after infusion based on the fundus photographs. Blood pressure was monitored during infusion. The eyes were removed after 24 *** to retinal ganglion cell(RGC) was analyzed by histology.·RESULTS: Retina became whiten and papilla optic was pale during perfusion. Measurements showed significant decrease in retinal artery and vein diameter during perfusion in all of the four groups at the proximal of the edge of the optic disc. The changes were significant in the 100 mm Hg-3min group and 100 mm Hg-5min group compared with 60 mm Hg-3min group(P 1=0.025, P 2=0.000).The diameters in all the groups recovered completely after 30 min of reperfusion. The number of RGC)showed no significant changes at the IOP in 100 mm Hg with5 min compared with contralateral untreated eye(P >0.05).·CONCLUSION: Transient fluctuations during infusion lead to temporal changes of retinal vessels, which could affect the retinal blood circulation. The RGCs were not affected by this transient fluctuation. Further studies are necessary to evaluate the effect of pressure during realtime phacoemusification on retinal blood circulation.

关键词： ocular perfusion pressure retinal ischemia retinal ganglion cells animals

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Omics study reveals abnormal alterations of breastmilk proteins and metabolites in puerperant women with COVID-19

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Signal Transduction and Targeted Therapy 2020年第1期5卷 379-381页

作者： yin zhao You Shang Yujie Ren Yuanyuan Bie Yang Qiu yin Yuan Yun zhao Li Zou Shu-Hai Lin Xi Zhou Department of Obstetrics and Gynecology Union HospitalTongji Medical CollegeHuazhong University of Science and Technology430022 WuhanChina Department of Critical Care Medicine Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina Joint Laboratory of Infectious Diseases and Health Wuhan Institute of Virology&WuhanJinyintan HospitalCAS430023 WuhanChina State Key Laboratory of Virology Wuhan Institute of VirologyCenter for Biosafety Mega-ScienceChinese Academy of Sciences(CAS)430071 WuhanChina Center for Precision Translational Medicine of Wuhan Institute of Virology&Guangzhou Women and Children’s Medical Center 510120 GuangzhouChina State Key Laboratory of Cellular Stress Biology Innovation Center for Cell Signaling NetworkSchool of Life SciencesXiamen UniversityXiamenChina Department of Obstetrics and Gynecology Maternal and Child Hospital of Hubei Province430072 WuhanChina

Dear Editor,The nutrition contents of breastmilk directly participate in neonatal immune *** alternations of the components of breastmilk under the context of viral infection not only reflect the physiological changes in mothers but also affect neonatal immunity and metabolism via ***,we attempted to answer the important questions whether breastmilk production is affected by COVID-19 and whether breastfeeding is still a safe or recommended operation for COVID-19 puerperant women.

关键词： metabolism milk immunity

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Abnormal Systemic and Ocular Responses to the Valsalva Manoeuvre in Primary Open-Angle Glaucoma:A Case for Autonomic Failure?

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Current Medical Science 2023年第2期43卷 376-383页

作者： Bin-bin LIU Bo-wen zhao Fei-peng WU Tian HU yin zhao Hong ZHANG Department of Ophthalmology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China

Objective This study aimed to examine the association of primary open-angle glaucoma(POAG)with autonomic dysfunction by assessing the differences in systemic and ocular responses to an autonomic provocation test,the Valsalva manoeuvre(VM),between POAG patients and normal *** Forty POAG and forty control subjects were subjected to the *** and ocular parameters were measured at baseline,phase 2,and phase 4 of the VM(VM2 and VM4),where VM2 and VM4 are sympathetic and parasympathetic nervous activation states,*** rate variability was used to assess the autonomic nervous activity,among which the high-frequency component(HF)and the low-frequency(LF)/HF ratio were used as indices of parasympathetic and sympathetic activation,*** POAG patients demonstrated higher sympathetic activation(LF/HF ratio median:2.17 vs.1.53,P=0.000)than controls at baseline and exhibited attenuated sympathetic and parasympathetic responses(a smaller change in LF/HF and HF values)during the VM than *** VM,the intraocular pressure(IOP),mean blood pressure(MAP),mean ocular perfusion pressure(MOPP),and the Schlemm’s canal area(SCAR)increased from baseline to VM2 and then decreased from VM2 to VM4 in both the POAG and control groups(all P<0.05).However,when we compared the changes above,the fluctuations in IOP,MAP,and MOPP were more pronounced in POAG than in controls(all P<0.05),while the changes in amplitudes of SCAR were smaller in POAG(P<0.05).Furthermore,from VM2 to VM4,the choroid thickness(ChT)in the POAG group was significantly decreased,while it was unchanged in normal subjects(P=0.258).A regression analysis showed a significant correlation of the baseline LF/HF with IOP change values(ΔIOP)from baseline to VM2 in POAG(R^(2)=0.147,P=0.014).Conclusion Patients with POAG showed more pronounced fluctuations in IOP,MAP,MOPP and ChT during the VM than *** reactions could be associated with autonomic dysfunction in POAG.

关键词： primary open-angle glaucoma Valsalva manoeuvre autonomic dysfunction intraocular pressure Schlemm’s canal

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Dynamic stall control over an airfoil by NS-DBD actuation

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Chinese Physics B 2020年第10期29卷 370-379页

作者： He-Sen Yang Guang-yin zhao Hua Liang Biao Wei Science and Technology on Plasma Dynamics Laboratory Air Force Engineering UniversityXi'an 710038China State Key Laboratory of Aerodynamics China Aerodynamics Research and Development CenterMianyang 621000China

The wind tunnel test was conducted with an NACA 0012 airfoil to explore the flow control effects on airfoil dynamic stall by NS-DBD plasma actuation. Firstly, light and deep dynamic stall states were set, based on the static stall characteristics of airfoil at a Reynolds number of 5.8 × 105. Then, the flow control effect of NS-DBD on dynamic stall was studied and the influence law of three typical reduced frequencies (k = 0.05, k = 0.05, and k = 0.15) was examined at various dimensionless actuation frequencies (F+ = 1, F+ = 2, and F+ = 3). For both light and deep dynamic stall states, NS-DBD had almost no effect on upstroke. However, the lift coefficients on downstroke were increased significantly and the flow control effect at F+ = 1 is the best. The flow control effect of the light stall state is more obvious than that of deep stall state under the same actuation conditions. For the same stall state, with the reduced frequency increasing, the control effect became worse. Based on the in being principles of flow separation control by NS-DBD, the mechanism of dynamic stall control was discussed and the influence of reduced frequency on the dynamic flow control was analyzed. Different from the static airfoil flow separation control, the separated angle of leading-edge shear layer for the airfoil in dynamic stall state is larger and flow control with dynamic oscillation is more difficult. The separated angle is closely related to the effective angle of attack, so the effect of dynamic stall control is greatly dependent on the history of angles of attack.

关键词： flow control dynamic stall dielectric barrier discharge(DBD) nanosecond pulse reduced frequency

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Quantitative evaluation of eco-geotechnical measures for debris flow mitigation by improved vegetation-erosion model

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Journal of Mountain Science 2022年第7期19卷 2015-2026页

作者： LYU Li-qun XU Meng-zhen ZHOU Guan-yu WANG zhao-yin School of Soil and Water Conservation Beijing Forestry UniversityBeijing100083China State Key Laboratory of Hydroscience and Engineering Tsinghua UniversityBeijing100084China

Eco-geotechnical measures for debris flow mitigation and control have attracted wide attention,but the mitigation effect is lack of quantitative evaluation of coordinated *** order to evaluate the debris flow mitigation effect in the combinations of geotechnical engineering and ecological engineering,this study investigated the different trends of debris flows behaviour based on the sediment deposition on the gully bed and the loose material on the ***,this research proposed a new model involving vegetation coverage,source gravity energy and debris flow volume based on vegetation-erosion *** new model validated that the debris flow volume was proportional to the gravity energy of gravel and rock fragments on the hillslope and inversely proportional to the vegetation coverage in a dry-hot valley ***,a typical area in the valley of the Xiaojiang River in Yunnan Province,China was quantified with the new *** results showed that under different gravity energy conditions,the implementation order of check dam construction and afforestation was important for debris flow mitigation.

关键词： Debris flow Vegetation coverage Source energy Incision and deposition Afforestation Check dam Jiangjia Gully

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