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COVID-19 with asthma:A case report

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World Journal of Clinical Cases 2020年第15期8卷 3355-3364页

作者： ai-Ling Liu Ning Xu ai-Jun Li Department of Pulmonary and Critical Care Medicine Weihai Municipal HospitalShandong UniversityWeihai 264200Shandong ProvinceChina

BACKGROUND Coronavirus disease 2019(COVID-19)is a public health emergency of international *** global population lacks immunity to COVID-19 and is generally *** conditions,especially chronic respiratory diseases,may affect progression,treatment and prognosis of *** SUMMARY We report a patient with confirmed COVID-19 combined with *** took 41 d from disease onset to discharge to obtain two negative tests for this *** This case indicates the dynamic clinical characteristics,laboratory and computed tomography findings and adjustment of treatment,and the possible relationship between glucocorticoid therapy and coronavirus clearance.

关键词： COVID-19 Asthma Glucocorticoids Respiratory passage mucosa immune system Case report

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农村小学全科师范生核心素养体系构建

黑龙江教师发展学院学报 2025年第1期44卷 24-29页

作者：邱芳婷刘嫒宁夏师范大学教育科学学院宁夏固原756099

农村小学全科师范生核心素养体系构建是农村小学教师培养的关键。基于教师核心素养研究的历史梳理,依据学生核心素养发展理论、小学教师专业标准、小学教育专业师范生职业能力标准和教育部关于卓越教师的培养计划,考虑农村小学教育的实... 详细信息

农村小学全科师范生核心素养体系构建是农村小学教师培养的关键。基于教师核心素养研究的历史梳理,依据学生核心素养发展理论、小学教师专业标准、小学教育专业师范生职业能力标准和教育部关于卓越教师的培养计划,考虑农村小学教育的实践需求和全科师范生自身专业成长的现实需要,构建包括师德素养、知识素养、能力素养三个基本领域,服务农村的社会责任感、定向农村的职业认同感、自我修养、“两专多门”的学科知识、学科教学知识、农村教育情境知识、农村教育教学能力、自主发展能力等八个素养指标的核心素养体系,以期真正培养出“下得去、留得住、教得好”的农村小学全科教师。

关键词：农村小学全科师范生核心素养师德素养知识素养能力素养

L_1 adaptive controller design for hypersonic formation flight

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Science China(Technological Sciences) 2016年第10期59卷 1597-1608页

作者： CHEN Qi WAN Jing ai JianLiang Department of Aeronautics and Astronautics Fudan University Institute of Vehicle Design Fudan University

The design of an L_1 adaptive controller for hypersonic formation flight is presented. The traditional leader/wingman formation control problem is considered, with focused attention on dealing with the input disturbance and parametric variations, both of which are intrinsic properties of the system that result in undesired control performance. A proportional-derivative control scheme based on nonlinear dynamic inversion is implemented as the baseline controller, and an L_1 adaptive controller is augmented to the baseline controller to attenuate the effects of input disturbance and parametric variations. Simulation results illustrate the effectiveness of the proposed control scheme.

关键词： hypersonic flight control nonlinear dynamic inversion L1 adaptive control input disturbance parametric variation

L1 adaptive control of a generic hypersonic vehicle model with a blended pneumatic and thrust vectoring control strategy

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Science China(Information Sciences) 2017年第3期60卷 139-152页

作者： Qi CHEN Jing WAN Jianliang ai Department of Aeronautics and Astronautics Fudan University Institute of Vehicle Design Fudan University

The extreme aeroheating at hypersonic regime and the insufficient dynamic pressure in the near space limit the achievable performance of the hypersonic vehicles using aerosurfaces alone. In this paper, an integrated pneumatic and thrust vectoring control strategy is employed to design a control scheme for the longitudinal dynamics of a hypersonic vehicle model. The methodology reposes upon a division of the model dynamics, and an L1adaptive control architecture is applied to the design of the inner-loop and outer-loop controllers. Further, a control allocation algorithm is developed to coordinate pneumatic and thrust vectoring control. Simulation results demonstrate that the allocation algorithm is effective in control coordination, and the proposed control scheme achieves excellent tracking performance in spite of aerodynamic uncertainties.

关键词： hypersonic flight control L1 adaptive control thrust vectoring control allocation parametric uncertainty

Influences of pouring temperature and cooling rate on microstructure and mechanical properties of casting Al-Si-Cu aluminum alloy

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Acta Metallurgica Sinica(English Letters) 2012年第4期25卷 272-278页

作者： Xiaowu HU Fanrong ai Hong YAN School of Mechanical Electrical Engineering Nanchang UniversityNanchang 330031China

This paper investigated the influences of pouring temperature and cooling rate on the microstructure development and mechanical properties for casting A1-Si-Cu aluminum alloy. The microstructure of the as-cast samples was characterized by an optical microscope. The results showed that the dendrite arm spacing （DAS,）,） is well refined by pouring at a higher temperature. The A decreases with increasing pouring temperature due to the multiplication of the nucleation sites in the superheating liquid melt, and the mechanical properties, such as microhardness and ultimate tensile strength increase correspondingly, while the elongation decreases. The relationships between microhardness and 3, for the samples cooled in metal mould and sand mould, are given as HV：l18.9 - 1.246A and HV=l15.2- 1.029A, respectively. The effects of the cooling rate controlled by using permanent mould casting and sand mould casing processes （the cooling medium is air and sand, respectively） on the dendrite arm spacing and mechanical properties are similar to the effect of the pouring temperature.

关键词： Pouring temperature Cooling rate Microstructure Aluminumalloy Mechanical property

Effect of Oxidation-Induced Material Parameter Variation on the High Temperature Oxidation Behavior of Nickel

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Acta Mechanica Solida Sinica 2016年第4期29卷 337-344页

作者： Chao Wang Shigang ai Daining Fang State Key Laboratory for Turbulence and Complex Systems College of Engineering Peking University Institute of Engineering Mechanics Beijing Jiaotong University Beijing Institute of Technology

In high temperature oxidation environment, the oxidation reaction will induce variations in material parameters, such as Young's modulus, thermal expansion coefficient (CTE), coefficient of oxygen diffusion (COD), etc. The oxidation -induced material parameter variations should be considered in high temperature mechanical analysis. In this paper, high temperature oxidation behavior of an oxide film/metal substrate system was investigated through a modified phase field approach. The oxidative stress and oxidation weight gain induced by high temperature oxidation were studied. Effects of Young's modulus, COD and CTE on oxidative stress in the oxide film were studied particularly. The simulation results showed that a better agreement with the experimental results could be obtained when considering the oxidation -induced material parameter variations in the high temperature mechanical analysis of oxide film/metal substrate system. The simulation results demonstrated that oxidative stress and oxidation weight gain were more sensitive to the variation of Young's modulus than to the variations of COD and CTE.

关键词： high temperature oxidation phase field simulation material parameter variation oxidative stress oxidation weight gain

Gain self-scheduled H_∞ control for morphing aircraft in the wing transition process based on an LPV model

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Chinese Journal of Aeronautics 2013年第4期26卷 909-917页

作者： Yue Ting Wang Lixin ai Junqiang School of Aeronautic Science and Engineering Beihang University The First aircraft Design Institute of AVIC

This article investigates gain self-scheduled H 1 robust control system design for a tailless fold- ing-wing morphing aircraft in the wing shape varying process. During the wing morphing phase, the aircraft＇s dynamic response will be governed by time-varying aerodynamic forces and moments. Nonlinear dynamic equations of the morphing aircraft are linearized by using Jacobian linearization approach, and a linear parameter varying （LPV） model of the morphing aircraft in wing folding is obtained. A multi-loop controller for the morphing aircraft is formulated to guarantee stability for the wing shape transition process. The proposed controller uses a set of inner-loop gains to provide stability using classical techniques, whereas a gain self-scheduled H 1 outer-loop controller is devised to guarantee a specific level of robust stability and performance for the time-varying dynamics. The closed-loop simulations show that speed and altitude vary slightly during the whole wing folding process, and they converge rapidly after the process ends. This proves that the gain self-scheduled H 1 robust controller can guarantee a satisfactory dynamic performance for the morphing aircraft during the whole wing shape transition process. Finally, the flight control system＇s robustness for the wing folding process is verified according to uncertainties of the aerodynamic parameters in the nonlinear model.

关键词： Gain self-scheduled H 1 robust control Linear parameter varying Morphing aircraft Wing transition

Nanoparticulate X-ray CT contrast agents

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Science China Chemistry 2015年第5期58卷 753-760页

作者： Wenya He Kelong ai Lehui Lu State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences

X-ray computed tomography(CT) has been widely used as a powerful diagnostic tool in clinics because it can provide high-resolution 3D tomography of the anatomic structure based on the distinctive X-ray absorptions between different tissues. Currently, CT contrast agents are mainly small iodinated molecules, which suffer from drawbacks such as short blood- retention time, nonspecific in vivo biodistribution, and renal toxicity. Utilization of nanoparticles as potential CT contrast agents to overcome the aforementioned issues has advanced rapidly. In this mini review, we introduce current research efforts in the development of nanoparticulate CT contrast agents and discuss the challenges for additional breakthroughs in this field.

关键词： X-ray computed tomography (CT) contrast agents nanoparticles iodine

The behavior of deep convective clouds over the warm pool and connection to the Walker circulation

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Science China Earth Sciences 2018年第11期61卷 1605-1621页

作者： Wenjing SHI Ziniu XIAO Yufei ai Beijing Institute of Applied Meteorology Beijing 100029 China Beijing Goldwind Science & Creation Windpower Equipment Co. Ltd. Xinjiang Goldwind Science & Technology Co. Ltd. Beijing 100176 China State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Laboratory for Climate and Ocean-Atmosphere Studies Department of Atmospheric and Oceanic Sciences School of Physics Peking University Beijing 100871 China

As the deep convective clouds(DCCs) over the western Pacific and Indian Ocean warm pool may play different roles in the climate system, variations in DCC properties over these two sectors are investigated and compared. The DCC intensity and area varies more significantly in the Indian Ocean than the western Pacific sector, while the DCC frequency is comparable in both sectors at the seasonal scale. Although the Indian Ocean sector is strongly dominated by the seasonal evolution, the interannual variations in the two sectors are comparable for all three DCC properties(frequency, intensity, and area). Besides,Walker circulation is closely correlated with the interannual variability of DCCs in both sectors. The Walker circulation strengthens(weakens) as the DCCs shift eastward(westward) over the Indian Ocean sector and westward(eastward) over the western Pacific sector. When more or stronger DCCs occur over the Indian Ocean sector(western Pacific sector), the Walker circulation becomes stronger(weaker) and shifts westward(eastward). Interestingly, the response of the Walker circulation to DCC variability over the warm pool is asymmetry. The asymmetry response of the Walker circulation to the negative and positive DCC anomaly may be related to the non-linearity internal variability of the atmosphere. DCCs over the Indian Ocean sector have a much weaker nonlinear correlation with the Walker circulation than DCCs over the western Pacific sector.

关键词： Satellite data Deep convective clouds Asymmetry response Walker circulation