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Nano Research 2024年第1期17卷 297-306页

作者： Jing Xie zhenjiang Lu yue Feng Jianguo Huang Jindou Hu Aize Hao Yali Cao State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources College of ChemistryXinjiang UniversityUrumqi 830046China

Defect modulation currently plays a decisive role in addressing the poor photoabsorption,sluggish electron hole separation,and high CO_(2)activation barrier in photocatalytic CO_(2)***,hunting for a straightforward strategy to balance the concentration of oxygen vacancy and metal cation defect in one photocatalyst is still a great ***,a bismuth vacancies BiOBr nanosheets(BiOBr-1)on the exposed[001]facets were constructed via an acetic acid molecule modification strategy,which can repair oxygen defect by bismuth vacancy in low-temperature solid-state chemical *** from the formed bismuth defects that can not only broaden light absorption and elevate charge separation efficiency,but also enhance adsorption and activation of CO_(2)molecules,the evolution rates of photocatalytic CO_(2)conversion into CO(71.23μmol·g^(-1)·h^(-1))and CH4(8.90μmol·g^(-1)·h^(-1))attained by BiOBr-1 are superior 7.1 and 11 times to that of plate-like *** photocatalytic mechanisms including adsorption concentration and activation process of CO_(2)are further revealed by the in situ diffuse reflectance infrared flourier transform spectra(DRIFTS).This finding of the existence of distinct defects in ultrathin nanosheets undoubtedly leads to new possibilities for photocatalyst design using two-dimensional materials with high solar-driven photocatalytic activity.

关键词： solid-state synthesis BiOBr metal vacancies photocatalysis carbon dioxide reduction

Virtual sensing method for monitoring vibration of continuously variable configuration structures using long short-term memory networks

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Chinese Journal of Aeronautics 2020年第1期33卷 244-254页

作者： zhenjiang yue Li LIU Teng LONG Yuanchen MA School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Key Laboratory of Dynamics and Control of Flight Vehicle Ministry of EducationBeijing 100081China

Vibration monitoring by virtual sensing methods has been well developed for linear timeinvariant structures with limited ***,few methods are proposed for Time-Varying(TV)structures which are inevitable in aerospace *** core of vibration monitoring for TV structures is to describe the TV structural dynamic characteristics with accuracy and *** paper propose a new method using the Long Short-Term Memory(LSTM)networks for Continuously Variable Configuration Structures(CVCSs),which is an important subclass of TV *** configuration parameters are used to represent the time-varying dynamic characteristics by the‘‘freezing"*** relationship between TV dynamic characteristics and vibration responses is established by LSTM,and can be generalized to estimate the responses with unknown TV processes benefiting from the time translation invariance of LSTM.A numerical example and a liquid-filled pipe experiment are used to test the performance of the proposed *** results demonstrate that the proposed method can accurately estimate the unmeasured responses for CVCSs to reveal the actual characteristics in time-domain and ***,the average one-step estimation time of responses is less than the sampling ***,the proposed method is promising to on-line estimate the important responses of TV structures.

关键词： Data-based method Recurrent neural networks Time-varying structure Vibration monitoring Virtual sensing

A reduced order aerothermodynamic modeling framework for hypersonic vehicles based on surrogate and POD

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Chinese Journal of Aeronautics 2015年第5期28卷 1328-1342页

作者： Chen Xin Liu Li Long Teng yue zhenjiang School of Aerospace Engineering Beijing Institute of Technology Key Laboratory of Dynamics and Control of Flight Vehicle Ministry of Education Beijing Institute of Technology

Aerothermoelasticity is one of the key technologies for hypersonic vehicles. Accurate and efficient computation of the aerothermodynamics is one of the primary challenges for hypersonic aerothermoelastic analysis. Aimed at solving the shortcomings of engineering calculation, compu- tation fluid dynamics （CFD） and experimental investigation, a reduced order modeling （ROM） framework for aerothermodynamics based on CFD predictions using an enhanced algorithm of fast maximin Latin hypercube design is developed. Both proper orthogonal decomposition （POD） and surrogate are considered and compared to construct ROMs. Two surrogate approaches named Kriging and optimized radial basis function （ORBF） are utilized to construct ROMs. Furthermore, an enhanced algorithm of fast maximin Latin hypercube design is proposed, which proves to be helpful to improve the precisions of ROMs. Test results for the three-dimensional aerothermody- namic over a hypersonic surface indicate that： the ROMs precision based on Kriging is better than that by ORBF, ROMs based on Kriging are marginally more accurate than ROMs based on POD- Kriging. In a word, the ROM framework for hypersonic aerothermodynamics has good precision and efficiency.

关键词： Hypersonic vehicles Aerothermodynamic Reduced order model(ROM) Surrogate Proper orthogonaldecomposition (POD)

Adding-Point Strategy for Reduced-Order Hypersonic Aerothermodynamics Modeling Based on Fuzzy Clustering

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Chinese Journal of Mechanical Engineering 2016年第5期29卷 983-991页

作者： CHEN Xin LIU Li ZHOU Sida yue zhenjiang Key Laboratory of Dynamics and Control of Flight Vehicle of Ministry of Education Beijing Institute of Technology School of Aerospace Engineering Beijing Institute of Technology

Reduced order models（ROMs） based on the snapshots on the CFD high-fidelity simulations have been paid great attention recently due to their capability of capturing the features of the complex geometries and flow configurations. To improve the efficiency and precision of the ROMs, it is indispensable to add extra sampling points to the initial snapshots, since the number of sampling points to achieve an adequately accurate ROM is generally unknown in prior, but a large number of initial sampling points reduces the parsimony of the ROMs. A fuzzy-clustering-based adding-point strategy is proposed and the fuzzy clustering acts an indicator of the region in which the precision of ROMs is relatively low. The proposed method is applied to construct the ROMs for the benchmark mathematical examples and a numerical example of hypersonic aerothermodynamics prediction for a typical control surface. The proposed method can achieve a 34.5% improvement on the efficiency than the estimated mean squared error prediction algorithm and shows same-level prediction accuracy.

关键词： reduced order model fuzzy clustering hypersonic aerothermodynamics adding-point strategy

基于自适应采样的高超声速飞行器气动热全局快速预示

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航空学报 2023年第6期44卷 133-150页

作者：杨国涛岳振江刘莉北京理工大学宇航学院北京100081 北京理工大学飞行器动力学与控制教育部重点实验室北京100081

高超声速飞行器热防护系统设计中高精度气动热分析模型使得设计计算成本不断增加,基于数据驱动的气动热环境预示方法受到广泛关注。针对有限高精度模型计算成本下提升全局预示精度的问题,提出一种基于模糊聚类的批量自适应采样方法。根... 详细信息

高超声速飞行器热防护系统设计中高精度气动热分析模型使得设计计算成本不断增加,基于数据驱动的气动热环境预示方法受到广泛关注。针对有限高精度模型计算成本下提升全局预示精度的问题,提出一种基于模糊聚类的批量自适应采样方法。根据预示误差分布特征通过聚类采用超球分割构建采样影响域,兼顾误差较大的重点采样域与全局探索;通过当地误差评分系数加权构建采样拒绝域,减小新增样本冗余;结合maxmin准则在综合确定的重点采样空间中新增样本,提升采样质量,进而实现预示模型全局精度快速提升。数值测试算例表明,所提方法与One-Shot、APSFC、CV-Voronoi方法相比能有效降低所需采样规模,加速提升预示精度。通过类HTV-2飞行器气动热快速预示实例,验证了方法的有效性与工程实用性。

关键词：自适应采样模糊聚类快速预示高超声速气动热

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火箭整流罩锥壳夹层结构不确定性轻量化设计

北京航空航天大学学报 2023年第3期49卷 625-635页

作者：董欣心岳振江王志刘莉北京理工大学宇航学院北京100081

为分析运载火箭整流罩锥壳夹层结构不确定性对结构热稳定性的影响并指导结构的轻量化设计,建立整流罩前锥段夹层圆锥壳模型,并建立温度场模型,据此对圆锥壳开展热稳定性分析,推导力热联合载荷作用下整流罩前锥段夹层结构失稳临界轴压。... 详细信息

为分析运载火箭整流罩锥壳夹层结构不确定性对结构热稳定性的影响并指导结构的轻量化设计,建立整流罩前锥段夹层圆锥壳模型,并建立温度场模型,据此对圆锥壳开展热稳定性分析,推导力热联合载荷作用下整流罩前锥段夹层结构失稳临界轴压。在此基础上,针对主要不确定性因素,开展灵敏度分析并建立区间不确定性优化模型,采用区间可能度方法将其转化为确定性问题,并采用遗传算法-区间分析算法(GA-CIAM)实现结构优化设计。计算结果表明:考虑气动力/热载荷及材料参数不确定性影响,对整流罩前锥段结构开展优化设计,在满足设计要求的前提下,有效实现结构轻量化。

关键词：整流罩锥壳夹层结构热稳定性分析区间不确定性优化轻量化设计

Target parameter estimation for OTFS-integrated radar and communications based on sparse reconstruction preprocessing

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Frontiers of Information Technology & Electronic Engineering 2024年第5期25卷 742-754页

作者： Zhenkai ZHANG Xiaoke SHANG yue XIAO Ocean College Jiangsu University of Science and TechnologyZhenjiang 212003China

Orthogonal time-frequency space(OTFS)is a new modulation technique proposed in recent years for high Doppler wireless *** solve the parameter estimation problem of the OTFS-integrated radar and communications system,we propose a parameter estimation method based on sparse reconstruction preprocessing to reduce the computational effort of the traditional weighted subspace fitting(WSF)***,an OTFS-integrated echo signal model is ***,the echo signal is transformed to the time domain to separate the target angle from the range,and the range and angle of the detected target are coarsely estimated by using the sparse reconstruction ***,the WSF algorithm is used to refine the search with the coarse estimate at the center to obtain an accurate *** simulations demonstrate the effectiveness and superiority of the proposed parameterestimation algorithm.

关键词： Integrated radar and communications system Orthogonal time-frequency space Target parameter estimation Sparse reconstruction Weighted subspace fitting

基于本征正交分解和代理模型的高超声速气动热模型降阶研究

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航空学报 2015年第2期36卷 462-472页

作者：陈鑫刘莉岳振江北京理工大学宇航学院北京100081 北京理工大学飞行器动力学与控制教育部重点实验室北京100081

气动热弹性分析是高超声速飞行器设计的关键技术之一。高超声速飞行器气动热的准确快速预测是气动热弹性分析的重要前提。针对当前气动加热工程计算、数值计算和实验研究均不能很好满足设计要求的问题,采用本征正交分解(POD)与代理模型(... 详细信息

气动热弹性分析是高超声速飞行器设计的关键技术之一。高超声速飞行器气动热的准确快速预测是气动热弹性分析的重要前提。针对当前气动加热工程计算、数值计算和实验研究均不能很好满足设计要求的问题,采用本征正交分解(POD)与代理模型(Surrogate)技术结合的模型降阶(POD-Surrogate)方法,建立了一种快速高效的高超声速气动热降阶模型框架。针对典型高超声速三维翼面气动热预测研究结果表明:当保留的POD基模态个数大于20时,PODKriging方法和POD-RBF(Radial Basis Function)方法的降阶模型得到的翼面温度分布与计算流体力学(CFD)计算温度L∞平均误差分别达到6%和14%,相对均方根误差(NRMSE)平均误差分别达到4%和12%,继续增加POD的基模态并不能提高降阶模型的预测精度;针对高超声速机翼气动热计算,POD-Kriging方法比POD-RBF方法具有更高的精度;针对典型的高超声速三维翼面气动热预测表明:基于POD-Surrogate方法的气动热降阶模型具有较高的精度和效率。

关键词：高超声速气动热本征正交分解代理模型降阶模型

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运载火箭结构工作模态参数辨识研究综述

弹箭与制导学报 2022年第1期42卷 60-70页

作者：马庆港王紫扬康杰岳振江刘莉北京理工大学宇航学院北京100081 北京宇航系统工程研究所北京100076 南京航空航天大学航天学院南京211106

针对运载火箭结构工作模态分析问题,在对国内外研究现状及成果的调研基础上,对运载火箭结构工作模态参数辨识的研究现状及方法进行回顾及介绍。在已有工作基础上,总结了运载火箭结构工作模态参数的特点及辨识的基本流程,获取准确的工作... 详细信息

针对运载火箭结构工作模态分析问题,在对国内外研究现状及成果的调研基础上,对运载火箭结构工作模态参数辨识的研究现状及方法进行回顾及介绍。在已有工作基础上,总结了运载火箭结构工作模态参数的特点及辨识的基本流程,获取准确的工作模态参数对于运载火箭有限元模型修正、自适应控制、实时状态监测等具有重要意义;分析了运载火箭结构工作模态参数辨识的研究趋势和发展方向,主要包括鲁棒辨识算法、模态天地差异性分析、基于在线模态参数辨识的智能控制与决策等,以期为我国相关技术的研究发展和工程应用有所启示。

关键词：运载火箭结构模态参数工作模态辨识

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考虑材料烧蚀的整流罩结构热稳定性优化设计

战术导弹技术 2023年第3期 51-58页

作者：王志岳振江尹莲花陈友伟刘莉北京理工大学宇航学院北京100081 飞行器动力学与控制教育部重点实验室北京100081 北京宇航系统工程研究所北京100076

为提高整流罩设计过程中烧蚀热响应预测及热应力对临界承载能力影响的准确性,提出了一种考虑材料烧蚀的整流罩结构热稳定性优化设计流程。考虑整流罩防护层热传导、热解吸热、热解气体流动及烧蚀后退,结构层热传导,建立热响应分析模型;... 详细信息

为提高整流罩设计过程中烧蚀热响应预测及热应力对临界承载能力影响的准确性,提出了一种考虑材料烧蚀的整流罩结构热稳定性优化设计流程。考虑整流罩防护层热传导、热解吸热、热解气体流动及烧蚀后退,结构层热传导,建立热响应分析模型;应用一阶剪应变理论建立热屈曲平衡方程得到锥壳热稳定性分析模型。对整流罩前锥段进行优化设计,获得了前锥段结构设计参数,减轻了前锥段结构质量。算例结果表明,所提方法可通过精细化分析有效缩减设计冗余,对整流罩结构设计具有指导意义。

关键词：整流罩烧蚀热响应热应力优化设计稳定性热解