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Flight dynamics characteristics of canard rotor/wing aircraft in helicopter flight mode

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Chinese Journal of Aeronautics 2019年第7期32卷 1577-1587页

作者： Honggang Gao ao he Zhenghong Gao Yang NA Yangping DENG School of Aeronautics Northwestern Polytechnical University

The aerodynamic layout of the Canard Rotor/Wing(CRW) aircraft in helicopter flight mode differs significantly from that of conventional helicopters. In order to study the flight dynamics characteristics of CRW aircraft in helicopter mode, first, the aerodynamic model of the main rotor system is established based on the blade element theory and wind tunnel test results. The aerodynamic forces and moments of the canard wing, horizontal tail, vertical tail and fuselage are obtained via theoretical analysis and empirical formula. The flight dynamics model of the CRW aircraft in helicopter mode is developed and validated by flight test data. Next, a method of model trimming using an optimization algorithm is proposed. The flight dynamics characteristics of the CRW are investigated by the method of linearized small perturbations via Simulink. The trim results are consistent with the conventional helicopter characteristics, and the results show that with increasing forward flight speed, the canard wing and horizontal tail can provide considerable lift,which reflects the unique characteristics of the CRW aircraft. Finally, mode analysis is implemented for the linearized CRW in helicopter mode. The results demonstrate that the stability of majority modes increases with increasing flight speed. However, one mode that diverges monotonously,and the reason is that the CRW helicopter mode has a large vertical tail compared to the conventional helicopter. The results of the dynamic analysis provide optimization guidance and reference for the overall design of the CRW aircraft in helicopter mode, and the model developed can be used for control system design.

关键词： Canard rotor/wing aircraft Dynamics analysis Flight dynamics helicopter Linearization Model building

Full mode flight dynamics modelling and control of stopped-rotor UAV

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Chinese Journal of Aeronautics 2022年第10期35卷 95-105页

作者： ao he Honggang Gao Shanshan ZHANG Zhenghong Gao Bodi MA Lulu CheN Wei DAI School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China School of Civil Aviation Northwestern Polytechnical UniversityXi'an 710072China

The Stopped-Rotor(SR)UAV combines the advantages of vertical take-off and landing of helicopter and high-speed cruise of fixed-wing *** the same time,it also has a unique aerodynamic layout,which leads to great differences in the control and aerodynamic characteristics of various flight modes,and brings great challenges to the flight dynamics modelling and control in full-mode *** this paper,the flight dynamics modelling and control method of SR UAV in full-mode flight is ***,based on the typical flight profile of SR UAV when performing missions,using the theory and method of fuzzy mathematics,the T-S flight dynamics model of SR UAV in full-mode flight is established by synthesizing the flight dynamics model of each flight ***,an explicit model tracking and parameter adjusting control system based on fuzzy theory is designed to enhance the stability of the inner loop of SR UAV in full-mode flight,which effectively reduces the coupling between axes and improves the control quality of the ***,the outer loop control system is designed by using classical control method,and the control law of SR UAV in full-mode automatic flight is *** simulation results show that the proposed control system design method is feasible and effective,which lays a solid foundation for the subsequent engineering implementation of the SR UAV.

关键词： Full-mode control High-speed helicopter Model building Stopped-rotor aircraft Variable parameter stabilization

Yield potential and stability in super hybrid rice and its production strategies

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Journal of Integrative Agriculture 2017年第5期16卷 1009-1017页

作者： HUANG Min TANG Qi-yuan ao he-jun ZOU Ying-bin Southern Regional Collaborative Innovation Center for Grain and Oil Crops(CICGO) Hunan Agricultural UniversityChangsha 410128P.R.China

China＇s Super Hybrid Rice Breeding Program has made significant progress over the past two decades. In this paper, we reviewed our studies on the yield potential and stability in super hybrid rice and discussed the strategies for super hybrid rice production. The results of our studies show that rice yield potential has been increased by 12% in super hybrid cultivars as compared with ordinary hybrid and inbred cultivars. The higher grain yields in super hybrid rice cultivars are attributed to larger panicle size coupled with higher biomass production or higher harvest index. However, grain yields in super hybrid rice cultivars vary widely among locations depending on soil and climatic factors. Therefore, it is important to tailor target yield to local conditions in super hybrid rice production. The target yield for super hybrid rice production can be determined by the average yield method or the regression model method. Improving soil quality is critical to achieving the target yield in super hybrid rice production. Favorable crop rotations such as rice-oilseed rape and novel soil management practices, such as biochar addition, are effective approaches to improve soil quality. It is needed to develop simplified cultivation tech- nologies for super hybrid rice to meet the changes in socioeconomic environments during the period of transition. There are such technologies as no-tillage direct seeding and mechanized transplanting at high hill density with single seedling per hill.

关键词： mechanized transplanting no-tillage direct seeding super hybrid rice target yield yield potential yield stability

Hydrodynamic Performance and Power Absorption of A Coaxial DoubleBuoy Wave Energy Converter

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China Ocean Engineering 2023年第3期37卷 378-392页

作者： LI De-min DONG Xiao-chen LI Yan-ni HUANG he-ao SHI Hong-da College of Engineering Ocean University of ChinaQingdao 266400China Shandong Provincial Key Laboratory of Ocean Engineering Qingdao 266100China Qingdao Municipal Key Laboratory of Ocean Renewable Energy Ocean University of ChinaQingdao 266100China

As an important wave energy converter(WEC),the double-buoy device has advantages of wider energy absorption band and deeper water adaptability,which attract an increasing number of attentions from *** paper makes an in-depth study on double-buoy WEC,by means of the combination of model experiment and numerical *** Response Amplitude Operator(Rao)and energy capture of the double-buoy under constant power take-off(PTO)damping are investigated in the model test,while the average power output and capture width ratio(CWR)are calculated by the numerical simulation to analyze the influence of the wave condition,PTO,and the geometry parameters of the *** AQWA-Fortran united simulation sy stem,including the secondary developme nt of AQWA software coupled with the flowchart of the Fortran code,models a new dynamic *** viscous damping and hydraulic friction from WEC system are measured from the experimental results,and these values are added to the equation of *** a result,the energy loss is contained in the final numerical model the by united simulation *** the developed numerical model,the optimal period of energy capture is *** power capture reaches the maximum value under the outer buoy's natural *** paper gives the peak value of the energy capture under the linear PTO damping force,and calculates the optimal mass ratio of the device.

关键词： coaxial double-buoy wave energy converter physical model experiment numerical simulation hydrodynamic performance

Relationship Between Grain Yield and Yield Components in Super Hybrid Rice

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Agricultural Sciences in China 2011年第10期10卷 1537-1544页

作者： HUANG Min ZOU Ying-bin JIANG Peng XIA Bing Md Ibrahim ao he-jun College of Agronomy Hunan Agricultural University Changsha 410128 P.R.China

Chinese super hybrid rice breeding project has developed many new varieties with great yield potential. It is controversial which yield component should be emphasized in super hybrid rice production. The present study was conducted to compare super hybrid rice with common hybrid and super inbred rice and analyze contributions of yield components to grain yield of super hybrid rice under experimental conditions, and evaluate relationships between grain yield and yield components of super hybrid rice in farmer’s paddy fields. Field experiments were done in Changsha, Guidong, and Nanxian, Hunan Province, China, from 2007 to 2009. Eight super hybrid varieties, one common hybrid variety, and one super inbred variety were grown in each location and year. Rice production investigation was undertaken in high-yielding （Guidong）, moderate-yielding （Nanxian）, and low-yielding （Ningxiang） regions of Hunan Province, China, in 2009. Grain yield and yield components were measured in both the field experiments and rice production investigation. Super hybrid rice varieties outyielded common hybrid and super inbred varieties across three locations and years. Yield potential has been increased by 11.4% in super hybrid rice varieties compared with common and super inbred varieties. The higher yield of super hybrid varieties was attributed to improvement in panicle size. Panicles per m2 had the highest positive contribution to grain yield with the exception under yield level of 10.0 to 12.0 t ha-1, and was positively related to grain yield in farmer’s field at all of the high-, moderate-, and low-yielding regions. Our study suggests that panicle per m2 ought to be emphasized in super hybrid rice production.

关键词： super hybrid rice yield panicle number panicle size

Polymer Photovoltaic Cells

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复旦学报（自然科学版） 2005年第5期44卷 717-718页

作者： Jianhui Hou Chunhe Yang Erjun Zhou Chang he Zhan＇ ao Tan Youjun he Yongfang Li CAS Key Laboratory of Organic Solids Center for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

Polymer photovoltaic cells (PPVCs) have attracted much attention recently because of its easy fabrication, low cost and possibility to make flexible devices[1]. PPVC is composed of a conjugated polymer/C60blend layer (photosensitive layer) sandwiched between a transparent ITO electrode and a metal *** a light through ITO electrode irradiates on the photosensitive layer, the photons with appropriate energy will be absorbed by the conjugated polymer (CP) and excitons (electron-hole pair) are produced. The excitons move to the interface of CP/C60 where the electrons transfer to the LUMO of C60 and holes leave on the HOMO of the CP. The separated electrons migrate through the C60 network to and are collected by the metal electrode, and the holes migrate through the CP network to and are collected by the ITO electrode, so that the photocurrent and photovoltage are attained.

关键词：光电电池共轭聚合体太阳能电池电极电解液

Neural stem cell transplantation alleviates functional cognitive deficits in a mouse model of tauopathy

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Neural Regeneration Research 2022年第1期17卷 152-162页

作者： he-ao Zhang Chun-Xu Yuan Ke-Fu Liu Qi-Fan Yang Juan Zhao Hui Li Qing-Hu Yang Da Song Zhen-Zhen Quan Hong Qing Key Laboratory of Molecular Medicine and Biotherapy School of Life ScienceBeijing Institute of TechnologyBeijingChina

The mechanisms of the transplantation of neural stem cells(NSCs)in the treatment of Alzheimer’s disease remain poorly *** this study,NSCs were transplanted into the hippocampal CA1 region of the rTg(tau P301L)4510 mouse model,a tauopathy model that is thought to reflect the tau pathology associated with Alzheimer’s *** results revealed that NSC transplantation reduced the abnormal aggregation of tau,resulting in significant improvements in the short-term memory of the tauopathy model *** with wild-type and phosphate-buffered saline(PBS)-treated mice,mice that received NSC transplantations were characterized by changes in the expression of multiple proteins in brain tissue,particularly those related to the regulation of tau aggregation or *** Encyclopedia of Genes and Genomes(KEGG)pathway analysis and Gene Ontology(GO)function analysis revealed that these proteins were primarily enriched in pathways associated with long-term potentiation,neurogenesis,and other neurobiological *** in the expression levels of key proteins were verified by western blot *** data provided clues to improve the understanding of the functional capacity associated with NSC transplantation in Alzheimer’s disease *** study was approved by the Beijing Animal Ethics Association and Ethics Committee of Beijing Institute of Technology(approval ***-BIT-school of life science-2017-M03)in 2017.

关键词： Alzheimer’s disease cell transplantation neural differentiation neural stem cells proteomic analysis short-term memory tauopathy

Platelet derived TGF-β promote the proliferation of hepatocellular carcinoma cells by suppressing the expression of KLF6

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Platelet derived TGF-β promote the proliferation of hepatoc...

Chemical Mechanical Polishing of Ge_(2)Sb_(2)Te_(5) Using Abrasive-Free Solutions of Iron Trichloride

第十一届海峡两岸心血管科学研讨会、2017年全国心脑血管药理学术会议、中国卒中学会第一次新药研讨会

作者： he ao-Di Miao Shuo Ming Zhang-Yin

Aims:Platelets in the primary tumor microenvironment play crucial roles in the regulation of tumor proliferation,metastasis and *** and experimental evidences support that platelets and their extracts influence hepatocellular carcinoma(HCC) growth and *** the mechanism is still not fully *** aim of present study was to elucidate an unperceived mechanism of the proliferative effect of platelet on hepatocellular carcinoma(HCC) cells.

关键词： Platelet derived TGF promote the proliferation of hepatocellular carcinoma cells by suppressing the expression of KLF6

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Chinese Physics Letters 2012年第3期29卷 243-246页

作者： YAN Wei-Xia WANG Liang-Yong ZHANG Ze-Fang he ao-Dong ZHONG Min LIU Wei-Li WU Liang-Cai SONG Zhi-Tang State Key Laboratory of Functional Materials for Informatics Laboratory of NanotechnologyShanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050

Chemical mechanical polishing(CMP)of amorphous Ge_(2)Sb_(2)Te_(5)(GST)is studied using aqueous solutions of iron trichloride(FeCl_(3))as possible abrasive-free *** polishing performance of abrasive-free solutions is compared with abrasive-containing(3wt% colloidal silica)slurry in terms of polishing rate and surface *** experimental results indicate that the abrasive-free solutions have a higher polishing rate and better surface *** order to further investigate the polishing mechanism,post-CMP GST films using the abrasive-free solutions and abrasive-containing slurry are characterized by x-ray photoelectron ***,it is verified that the abrasive-free solutions have no influence on the electrical property of the post-CMP GST films through the resistivity test.

关键词： spectroscopy resistivity verified