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Aeroelastic optimization design for wing with maneuver load uncertainties

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Science China(Technological Sciences) 2010年第4期53卷 3102-3109页

作者： YANG Chao XIAO zhipeng wan ZhiQiang YAN De DAI YuTing School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China

An aeroelastic optimization design methodology for air vehicle considering the uncertainties in maneuver load conditions is presented and applied to a structural design process of low-aspect-ratio wing. An aerodynamic load correction model is developed and used to predict the critical load conditions with the perturbations of theoretical linear aerodynamic forces and experimental aerodynamic forces from wind-tunnel test, when concerning the uncertainties in use of theoretical linear and experimental aerodynamic forces. Three objective functions of critical loads are defined. The load evaluations for three wing sections are investigated in four characteristic maneuvers, and the most critical load conditions are confirmed by using the sequential quadratic programming method. On this basis, the aeroelastic optimization design employing the genetic-gradient hybrid algorithm is conducted, in which the objective is to minimize structural mass subject to the constraints of stress, deformation and flutter speed. The resulting optimal structure is heavier than the one simply based on the theoretical linear or experimental aerodynamic forces. However, it is more robust when encountering the critical load conditions in actual flight due to the consideration of uncertainties in aerodynamic forces in the early design phase, thereby, the risk of structural redesign can be reduced.

关键词： aeroelastic maneuver load uncertainty aerodynamic load correction robust experimental aerodynamic forces

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淋巴细胞活化基因-3敲除(Lag-3-/-)小鼠构建及初步表型分析

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中国实验动物学报 2020年第1期28卷 49-57页

作者：万颖寒慈磊王珏龚慧万志鹏奚骏何敏珠孙瑞林费俭沈如凌上海实验动物研究中心上海201203 模式生物技术联合实验室上海实验动物研究中心上海201203 同济大学生命科学与技术学院上海200092 上海南方模式生物科技股份有限公司上海201318

目的构建淋巴细胞活化基因-3(Lag-3)基因敲除小鼠,初步分析Lag-3基因敲除对小鼠表型影响,为后续Lag-3体内功能研究提供动物模型。方法利用CRISPR/Cas9技术结合受精卵显微注射构建敲除小鼠,通过分子鉴定筛选基因敲除阳性小鼠,利用RT-PCR... 详细信息

目的构建淋巴细胞活化基因-3(Lag-3)基因敲除小鼠,初步分析Lag-3基因敲除对小鼠表型影响,为后续Lag-3体内功能研究提供动物模型。方法利用CRISPR/Cas9技术结合受精卵显微注射构建敲除小鼠,通过分子鉴定筛选基因敲除阳性小鼠,利用RT-PCR和流式检测方法进一步验证Lag-3基因敲除小鼠体内Lag-3基因敲除效果;通过建立Con A诱导的肝损伤模型研究Lag-3基因在体内的功能。结果PCR和产物测序结果显示,获得了exon 2缺失的Lag-3基因敲除小鼠;该基因敲除纯合子小鼠(Lag-3-/-)经刀豆蛋白(Con A)刺激后,小鼠心脏、脾、肺、巨噬细胞和淋巴结中仅能检测到Lag-3 mRNA本底表达信号,小鼠巨噬细胞、脾细胞和淋巴结中仅能检测到非常低数量的Lag-3阳性细胞。表型分析发现,Lag-3基因的缺失显著减少了Con A诱导的小鼠外周血、骨髓和脾CD3+T细胞的数量,减轻了Con A诱发的急性肝损伤情况。结论成功构建Lag-3基因敲除小鼠模型,肝损伤过程中的体内功能研究显示,Lag-3缺失可以显著缓解Con A引发的肝损伤的发生。

关键词： Lag-3 CRISPR/Cas9 基因敲除刀豆蛋白

可重构智能表面辅助的V2I通信系统联合波束赋形算法

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电子与信息学报 2024年第8期46卷 3117-3125页

作者：仲伟志何艺段洪涛万诗晴范振雄朱秋明林志鹏南京航空航天大学电磁频谱空间认知动态系统工业与信息化部重点实验室南京211106 国家无线电监测中心北京100144

为解决基于信道先验知识的联合波束赋形方法受限于多变的车辆与交通基础设施(V2I)通信场景且信道估计开销过大等问题,该文结合环境态势感知,提出一种基于无线传播链路预测的联合波束赋形方法。该方法首先利用射线追踪模拟器构建了可重... 详细信息

为解决基于信道先验知识的联合波束赋形方法受限于多变的车辆与交通基础设施(V2I)通信场景且信道估计开销过大等问题,该文结合环境态势感知,提出一种基于无线传播链路预测的联合波束赋形方法。该方法首先利用射线追踪模拟器构建了可重构智能表面(RIS)辅助的V2I毫米波通信系统模型,通过改变环境态势以获取多样的无线传播链路数据来构建数据集。其次,使用该数据集训练基于机器学习的无线传播链路预测模型。最后,在最大发射功率约束条件下,构建了联合波束赋形问题模型,并基于预测结果采用交替迭代优化方法(AIOA)优化基站波束赋形矩阵和RIS相移矩阵,以实现同步通信车辆用户最小信干噪比(SINR)的最大化。仿真结果验证了该方法的有效性,通过引入非信道先验知识驱动,降低了信道探测开销,提高了该方法在V2I场景中的可行性。

关键词： V2I通信可重构智能表面联合波束赋形环境态势感知信道预测

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高功率大芯径环形光斑可调信号合束器的研究

中国激光 2024年第8期51卷 23-31页

作者：万志强杨瑷碧杨光华于珊胡紫晔唐吉龙魏志鹏长春理工大学高功率半导体激光国家重点实验室吉林长春130022 长春理工大学中山研究院广东中山528437 深圳市杰普特光电股份有限公司广东深圳518110

针对传统高功率光纤激光器焊接不稳定、飞溅量大、难以实现精密焊接的问题,设计了一种光斑可调的信号合束器,首次以50μm/70μm/600μm/620μm/660μm大芯径环形双芯光纤作为输出光纤,基于光束非相干合成技术,通过RSoft软件对合束器进... 详细信息

针对传统高功率光纤激光器焊接不稳定、飞溅量大、难以实现精密焊接的问题,设计了一种光斑可调的信号合束器,首次以50μm/70μm/600μm/620μm/660μm大芯径环形双芯光纤作为输出光纤,基于光束非相干合成技术,通过RSoft软件对合束器进行了模拟仿真,分析了其模场变化情况,设计的合束器满足绝热拉锥以及亮度守恒两个原则,调控拉锥比(TR)使其可以实现中心和外环独立工作。采用套管法将7根25μm/250μm光纤耦合到一起形成熔锥光纤束,再将其与输出光纤进行熔接,制成了高功率大芯径环形光斑可调信号合束器。此光纤合束器的传输效率≥98%,中心光束质量因子(M2)仅为1.76,此时中心端口输出功率为3.036 kW。而后对合束器进行了耐环境测试,合束器在低温与高温下表现出的传输特性良好。将该光斑可调的环形光斑信号合束器应用到激光器中,通过调节中心和外环激光功率,可以在任何温度环境下实现超高速焊接,为激光复合焊接提供了一种新途径。

关键词：激光器光纤合束器熔锥光纤束(TFB) 传输效率光束质量环境可靠性

Wavenumber-4 spectral component extracted from TIMED/SABER observations

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Earth and Planetary Physics 2020年第5期4卷 436-448页

作者： Xing Li WeiXing wan JinBin Cao zhipeng Ren Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China School of Space and Environment Beihang UniversityBeijing 100083China Key Laboratory of Space Environment Monitoring and Information Processing Ministry of Industry and Information TechnologyBeijing 100083China Beijing National Observatory of Space Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China University of the Chinese Academy of Sciences Beijing 100049China

The wavenumber spectral components WN4 at the mesosphere and low thermosphere(MLT)altitudes(70–10 km)and in the latitude range between±45°are obtained from temperature data(T)observed by the Sounding of the Atmosphere using Broadband Emission Radiometry(SABER)instruments on board the National Aeronautics and Space Administration(NASA)’s Thermosphere–Ionosphere–Mesosphere Energetics and Dynamics(TIMED)spacecraft during the 11-year solar period from 2002 to *** analyze in detail these spectral components WNk and obtain the main properties of their vertical profiles and global *** report that all of the wavenumber spectral components WNk occur mainly around 100 km altitude,and that the most prominent component is the wavenumber spectral component WN4 *** these long duration temperature data with results of previous investigations,we have found that the yearly variation of spectral component WN4 is similar to that of the eastward propagating non-migrating diurnal tide with zonal wavenumber 3(DE3)at the low latitudes,and to that of the semi-diurnal tide with zonal wavenumber 2(SE2)at the mid-latitudes:the amplitudes of the A4 are larger during boreal summer and autumn at the low-latitudes;at the mid-latitudes the amplitudes have a weak peak in *** addition,the amplitudes of component WN4 undergo a remarkable short period variation:significant day-to-day variation of the spectral amplitudes A4 occurs primarily in July and September at the *** summary,we conclude that the non-migrating tides DE3 and SE2 are likely to be the origins,at the low-latitudes and the mid-latitudes in the MLT region,respectively,of the observed wavenumber spectral component WN4.

关键词： TIMED observations wavenumber spectral components non-migrating tides short period variation

Simulated wave number 4 structure in equatorial F-region vertical plasma drifts

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Simulated wave number 4 structure in equatorial F-region ver...

A learning-based flexible autonomous motion control method for UAV in dynamic unknown environments

中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： zhipeng Ren,Weixing wan,Jiangang Xiong,and Libo Liu 1 Beijing National Observatory of Space Environment,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing,China. 2 Also at Wuhan Institute of Physics and Mathematics,Chinese Academy of Sciences,Wuhan,China. 3 Also at Graduate School of Chinese Academy of Sciences,Beijing, China.

[1]This article investigates the wave number 4 longitudinal structure in equatorial vertical E×B plasma drifts(V),using the Theoretical Ionospheric Dynamo Model,Institute of Geology and Geophysics,Chinese Academy of Sciences,Version II model and the DE3 tide wind from the Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED)/TIMED Doppler interferometer(TIDI) *** simulate this longitudinal structure and examine its intra-annual variations and the effect of different DE3 tide components and of different current components on *** find that this longitudinal structure shows obvious intra-annual variation,being strongest in northern summer and autumn and weakest in northern *** result is consistent with the intra-annual variation observed by Ren et al.(2009b).Our simulations also suggest that the eastward propagation of the DE3 tide can cause the eastward shift of the wave number 4 structure in *** wave number 4 structures in Vare mainly driven by a zonal wind component of DE3 tide,which contributes much more than the meridional wind component of DE3 tide to the wave number 4 structure in *** the influence of the coupling of ionospheric electric fields along the highly conducting magnetic field lines,the symmetric wind component of DE3 tide plays a more important role in the wave number 4 structure in Vthan the antisymmetric component *** intra-annual variations of the wave number 4 structure in Vare mainly controlled by the symmetric wind component of DE3 tide. Our simulations also suggest that the wave number 4 structures in Vare mainly driven by the Hall current.

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Journal of Systems Engineering and Electronics 2021年第6期32卷 1490-1508页

作者： wan Kaifang LI Bo GAO Xiaoguang HU Zijian YANG zhipeng School of Electronic and Information Northwestern Polytechnical UniversityXi’an 710072China

This paper presents a deep reinforcement learning(DRL)-based motion control method to provide unmanned aerial vehicles(UAVs)with additional flexibility while flying across dynamic unknown environments *** method is applicable in both military and civilian fields such as penetration and *** autonomous motion control problem is addressed through motion planning,action interpretation,trajectory tracking,and vehicle movement within the DRL *** DRL algorithms are presented by combining two difference-amplifying approaches with traditional DRL methods and are used for solving the motion planning *** improved Lyapunov guidance vector field(LGVF)method is used to handle the trajectory-tracking problem and provide guidance control commands for the *** contrast to conventional motion-control approaches,the proposed methods directly map the sensorbased detections and measurements into control signals for the inner loop of the UAV,i.e.,an end-to-end *** training experiment results show that the novel DRL algorithms provide more than a 20%performance improvement over the state-ofthe-art DRL *** testing experiment results demonstrate that the controller based on the novel DRL and LGVF,which is only trained once in a static environment,enables the UAV to fly autonomously in various dynamic unknown ***,the proposed technique provides strong flexibility for the controller.

关键词： autonomous motion control(AMC) deep reinforcement learning(DRL) difference amplify reward shaping

The source of tropospheric tides

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Earth and Planetary Physics 2020年第5期4卷 449-460页

With the method of Hough mode decomposition(HMD),the tidal sources of the three main tidal components,namely,the migrating components DW1(diurnal westward propagating wavenumber 1)and SW2(semidiurnal westward propagating wavenumber 2)and the non-migrating component DE3(diurnal eastward propagating wavenumber 3),at the tropospheric altitudes(1–12 km)and in the latitude range of±60°,were obtained from National Centers for Environmental Prediction(NCEP)Climate Forecast System Reanalysis(CFSR)data during the interval from 1988 to *** analyzed these sources in detail at 6 km and obtained the main properties of their yearly *** DW1 source was found to present a weak seasonal variation in the lower latitudes(about±10°–15°).That is,the amplitudes of the DW1 sources were larger in the summer months than in the winter months,and DW1 presented semi-annual variation near the equator(±10°)such that the DW1 source was larger at the equinoxes than at the *** addition,the SW2 source was symmetric and was stronger in the southern hemisphere than in the northern *** SW2 source presented remarkable annual and semi-annual variation such that the amplitudes were largest during the March equinox months and larger during the June solstice *** contrast,DE3 appeared mainly around the equatorial latitudes within about±30°.The DE3 source presented remarkable semiannual variation that was larger around the solstices than the equinoxes in the southern hemisphere,and it was opposite in the northern *** HMD,we found that the tropospheric tides were primarily dominated by some leading propagating Hough modes,specifically,the(1,1),(2,3),and(3,3)modes;the influences of the other Hough modes were *** consequences of an El Niño–Southern Oscillation modulation of tidal amplitudes for the energy and momentum budgets of the troposphere may now be expected to attract *** summary,the above yearly variations of the main tidal sources and

关键词： tropospheric tides Hough mode decomposition yearly variations

Influence of annual atmospheric tide asymmetry on annual anomalies of the ionospheric mean state

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Earth and Planetary Physics 2020年第5期4卷 429-435页

作者： zhipeng Ren WeiXing wan JianGang Xiong Xing Li Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China Beijing National Observatory of Space Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of the Chinese Academy of SciencesBeijing 100049China School of Space and Environment Beihang UniversityBeijing 100083China Key Laboratory of Space Environment Monitoring and Information Processing Ministry of Industry and Information TechnologyBeijing 100083China

Through respectively adding June tide and December tide at the low boundary of the GCITEM-IGGCAS model (Global CoupledIonosphere–Thermosphere–Electrodynamics Model, Institute of Geology and Geophysics, Chinese Academy of Sciences), we simulate theinfluence of atmospheric tide on the annual anomalies of the zonal mean state of the ionospheric electron density, and report that thetidal influence varies with latitude, altitude, and solar activity level. Compared with the density driven by the December tide, the June tidemainly increases lower ionospheric electron densities (below roughly the height of 200 km), and decreases electron densities in thehigher ionosphere (above the height of 200 km). In the low-latitude ionosphere, tides affect the equatorial ionization anomaly structure(EIA) in the relative difference of electron density, which suggests that tides affect the equatorial vertical E×B plasma drifts. Although thetide-driven annual anomalies do not vary significantly with the solar flux level in the lower ionosphere, in the higher ionosphere theannual anomalies generally decrease with solar activity.

关键词： ionospheric annual anomalies atmospheric tide ionosphere–atmosphere coupling