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Near-surface wind field characteristics of the desert-oasis transition zone in Dunhuang,China

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Journal of Arid Land 2024年第5期16卷 654-667页

作者： PAN jiapeng ZHANG Kecun AN Zhishan ZHANG yu Key Laboratory of Desert and Desertification&Dunhuang Gobi and Desert Ecology and Environment Research Station Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China

The desert-oasis transition zone(DOTZ)serves as a buffer area between the desert and *** its wind field characteristics is of great significance for the prevention and control of aeolian disasters in the *** this study,we used meteorological data during 2013–2019 from the portable meteorological stations at five sites(site A on the edge of the oasis,sites B,C,and D in the DOTZ,and site O in the desert)in Dunhuang,China to analyze the near-surface wind field characteristics and their causes,as well as to reveal the key role of the DOTZ in oasis *** results showed that the mean wind speed,frequency of sand-driving wind,and directional variability of wind decreased from west to east within the DOTZ,and wind speed was significantly affected by air *** terrain influenced the prevailing winds in the region,mainly from northeast and *** some areas adjacent to the oasis were controlled by southeasterly *** indicated that the near-surface wind field characteristics of the DOTZ were caused by the combined effects of local terrain and surface hydrothermal *** site D,the annual drift potential(DP)was 24.95 vector units(VU),indicating a low wind energy environment,and the resultant drift direction(RDD)showed obvious seasonal ***,the DOTZ played an important buffering role between the desert and *** with the desert,the mean wind speed in the oasis decreased by 64.98%,and the prevailing wind direction was more *** results of this study will be useful in interpreting the aeolian activity of the DOTZ in Dunhuang.

关键词： desert-oasis transition zone near-surface wind field hydrothermal difference sand-driving wind aeolian environment Dunhuang

Group-based multiple pipe routing method for aero-engine focusing on parallel layout

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Frontiers of Mechanical Engineering 2021年第4期16卷 798-813页

作者： Hexiang yuAN jiapeng yu Duo JIA Qiang LIU Hui MA School of Mechanical Engineering and Automation Northeastern UniversityShenyang 110819China Key Laboratory of Vibration and Control of Aero-Propulsion System(Ministry of Education) Northeastern UniversityShenyang 110819China Shenyang Engine Research Institute of AECC Shenyang 110015China School of Information and Control Engineering Liaoning Petrochemical UniversityFushun 113001China

External pipe routing for aero-engine in limited three-dimensional space is a typical nondetermini-stic polynomial hard problem,where the parallel layout of pipes plays an important role in improving the utilization of layout space,facilitating pipe assembly,and *** paper presents an automatic multiple pipe routing method for aero-engine that focuses on parallel *** compressed visibility graph construction algorithm is proposed first to determine rapidly the rough path and interference relationship of the pipes to be *** on these rough paths,the information of pipe grouping and sequencing are obtained according to the difference degree and interference degree,***,a coevolutionary improved differential evolution algorithm,which adopts the coevolutionary strategy,is used to solve multiple pipe layout optimization *** using this algorithm,pipes in the same group share the layout space information with one another,and the optimal layout solution of pipes in this group can be obtained in the same evolutionary ***,to eliminate the minor angle deviation of parallel pipes that would cause assembly stress in actual assembly,an accurate parallelization processing method based on the simulated annealing algorithm is ***,the simulation results on an aero-engine demonstrate the feasibility and effectiveness of the proposed method.

关键词： multiple pipe routing optimization algorithm aero-engine pipe grouping parallel layout

工业制SO_(3)气体浓度实时检测及多元非线性回归建模

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化工进展 2022年第11期41卷 5737-5745页

作者：孔祥旭张玮胡恒于嘉朋张坤徐娜太原理工大学化学工程与技术学院山西太原030024

工业接触法制SO_(3)气体浓度高、腐蚀性强、交叉影响大,高精度实时检测困难,且原料流量与SO_(3)浓度的关系尚不明确,参数调节依赖经验。针对上述问题,采用AO2电化学氧传感器设计了一种工业制SO_(3)气体浓度的实时检测系统,并构建了输入... 详细信息

工业接触法制SO_(3)气体浓度高、腐蚀性强、交叉影响大,高精度实时检测困难,且原料流量与SO_(3)浓度的关系尚不明确,参数调节依赖经验。针对上述问题,采用AO2电化学氧传感器设计了一种工业制SO_(3)气体浓度的实时检测系统,并构建了输入空气、SO_(2)流量与输出SO_(3)浓度的多元非线性回归模型。SO_(3)气体浓度实时检测系统主要包括AO2电化学氧传感器、传感器调理电路、AD620放大电路及ADS1256 A/D转换电路,通过检测SO_(3)发生装置输入空气与输出混合气体中O_(2)浓度的毫伏级变化,间接测量SO_(3)浓度,避免了其他敏感气体的交叉影响,实验结果表明检测系统的检测时间为27s,灵敏度为111mV/%,偏差小于0.18%,稳定性良好,证明了检测系统的有效性;利用响应面法建立了预测SO_(3)浓度的三次多项式非线性回归模型,对该模型进行方差分析后结果显著,测试后均方误差(MSE)为0.0007174,相关系数(R^(2))为0.9929,拟合度好、预测精度高。

关键词：三氧化硫浓度实时检测仪器仪表模型预测

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Material patterning on substrates by manipulation of fluidic behavior

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National Science Review 2019年第4期6卷 758-766页

作者： Yitan Li Hao Wang Henglu Xu Shiting Wu Xuemei Li jiapeng yu Chaoyu Huang Zeyao Zhang Hao Sun Lu Han Meihui Li Anyuan Cao Zhenhai Pan Yan Li Key Laboratory for the Physics and Chemistry of Nanodevices Beijing National Laboratory of Molecular SciencesState Key Laboratory of Rare Earth Materials Chemistry and Applications College of Chemistry and Molecular Engineering Peking University Academy for Advanced Interdisciplinary Studies Peking University College of Engineering Peking University Electron Microscopy Laboratory Peking University Bruker (Beijing) Scientific Technology Co. Ltd. 6. Institute of Engineering ThermophysicsShanghai Jiao Tong University

Patterned materials on substrates are of great importance for a wide variety of applications. In solution-based approaches to material patterning, fluidic flow is inevitable. Here we demonstrate not only the importance of fluidic behavior but also the methodology of engineering the flow pattern to guide the material crystallization and assembly. We show by both experiment and simulation that substrate heating,which is generally used to accelerate evaporation, produces irregular complex vortexes. Instead, a top-heating–bottom-cooling(THBC) set-up offers an inverse temperature gradient and results in a single Marangoni vortex, which is desired for ordered nanomaterial patterning near the contact line. We then realize the fabrication of large-scale patterns of iodide perovskite crystals on different substrates under THBC conditions. We further demonstrate that harnessing the flow behavior is a general strategy with great feasibility to pattern various functional materials ranging from inorganic, organic, hybrid to biological categories on different substrates, presenting great potential for practical applications.

关键词： Marangoni flow temperature gradient large-scale material patterning flexible device contact line

一种集成工程规则和卡箍调整的启发式布管算法

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计算机集成制造系统 2023年第9期29卷 2981-2990页

作者：唐志柳强于嘉鹏马辉贾铎刘媛杰辽宁石油化工大学信息与控制工程学院辽宁抚顺113001 东北大学机械工程与自动化学院辽宁沈阳110819 中国航发集团沈阳发动机研究所辽宁沈阳110015

针对航空发动机外部管路布局规则多且效率低的问题,提出一种集成工程规则和卡箍调整的启发式布管算法。首先,在敷设层面内建立管路端口间的测地线方程,基于测地线建立路径的基准节点;其次,基于工程规则设计启发式搜索策略,快速求解符合... 详细信息

针对航空发动机外部管路布局规则多且效率低的问题,提出一种集成工程规则和卡箍调整的启发式布管算法。首先,在敷设层面内建立管路端口间的测地线方程,基于测地线建立路径的基准节点;其次,基于工程规则设计启发式搜索策略,快速求解符合工程规则的可行路径;在此基础上,为了使多管敷设方案满足双联卡箍约束,通过空间几何方法建立卡箍位姿变换方程,对多管敷设方案进行优化调整,实现基于双联卡箍约束的成束敷设。最后,通过多个敷设算例验证了该算法的可行性和高效性。

关键词：航空发动机管路布局测地线工程规则双联卡箍

Linear-Quadratic Pareto Cooperative Game for Mean-Field Backward Stochastic System

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Journal of Systems Science & Complexity 2024年第3期37卷 947-964页

作者： WANG yu School of Control Science and Engineering Shandong UniversityJinan 250061China

This paper focuses on a Pareto cooperative differential game with a linear mean-field backward stochastic system and a quadratic form cost functional. Based on a weighted sum optimality method, the Pareto game is equivalently converted to an optimal control problem. In the first place,the feedback form of Pareto optimal strategy is derived by virtue of decoupling technology, which is represented by four Riccati equations, a mean-field forward stochastic differential equation(MF-FSDE),and a mean-field backward stochastic differential equation(MF-BSDE). In addition, the corresponding Pareto optimal solution is further obtained. Finally, the author solves a problem in mathematical finance to illustrate the application of the theoretical results.

关键词： Backward stochastic differential equation linear-quadratic control mean-field Pareto optimality

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基于递归循环的层次化爆炸图自动生成方法

机械工程学报 2016年第13期52卷 175-188页

作者：于嘉鹏王健熙东北大学机械工程与自动化学院沈阳110004 中国人民解放军驻沈阳黎明航空发动机公司军事代表室沈阳110043

提出以递归循环和深度优先搜索层次化装配序列的策略自动生成复杂产品层次化爆炸图的方法。为使设计结构符合装配规划的要求,设计了可方便定义子装配体和编辑装配树的装配结构重构功能。为避免重复的干涉检测,研究干涉矩阵合成方法,通... 详细信息

提出以递归循环和深度优先搜索层次化装配序列的策略自动生成复杂产品层次化爆炸图的方法。为使设计结构符合装配规划的要求,设计了可方便定义子装配体和编辑装配树的装配结构重构功能。为避免重复的干涉检测,研究干涉矩阵合成方法,通过对原始装配关系信息的整合,柔性化生成面向层次化结构的装配关系矩阵。为降低大规模序列规划问题的复杂性,将整体规划任务分解为若干个及若干层级子任务,子任务内采用多规则筛选算法,以基于干涉矩阵的几何可行性为前提,并行性、连续性、稳定性和方向性等为优化筛选指标,循环构建序列。提出递归爆炸算法,循环对层次化装配序列进行深度优先搜索,实时计算已爆炸零部件的累积包围盒,从而确定待爆炸零件位移矢量,自动生成间隔均匀有序、结构紧凑且空间层次感强的爆炸图。开发了基于Siemens NX的装配规划系统Auto Assem,以减速器及汽车部件实例验证了方法的有效性。

关键词：装配序列规划层次化爆炸图递归循环扩展干涉矩阵累积包围盒

Topological Stability and Entropy for Certain Set-valued Maps

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Acta Mathematica Sinica,English Series 2024年第4期40卷 962-984页

作者： yu ZHANG yu Jun ZHU School of Mathematical Sciences Xiamen UniversityXiamen 361005P.R.China

In this paper,the dynamics(including shadowing property,expansiveness,topological stability and entropy)of several types of upper semi-continuous set-valued maps are mainly considered from differentiable dynamical systems points of *** is shown that(1)if f is a hyperbolic endomorphism then for eachε>0 there exists a C^(1)-neighborhood U of f such that the induced set-valued map F_(f,U)has theε-shadowing property,and moreover,if f is an expanding endomorphism then there exists a C^(1)-neighborhood U of f such that the induced set-valued map F_(f,U)has the Lipschitz shadowing property;(2)when a set-valued map F is generated by finite expanding endomorphisms,it has the shadowing property,and moreover,if the collection of the generators has no coincidence point then F is expansive and hence is topologically stable;(3)if f is an expanding endomorphism then for eachε>0 there exists a C^(1)-neighborhood U of f such that h(F_(f,U,ε))=h(f);(4)when F is generated by finite expanding endomorphisms with no coincidence point,the entropy formula of F is ***,the dynamics of the set-valued maps based on discontinuous maps on the interval are also considered.

关键词： Set-valued map orbit space hyperbolic endomorphism perturbation shadowing expansiveness topological stability entropy

A new liquid membrane diffusion model for characterizing the adsorption kinetics of europium by using a continuous measurement of adsorption platform

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Nuclear Science and Techniques 2024年第1期35卷 59-72页

作者： Hao-Qi yu Tao yu Jian-Hua Ye State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China CGN Cangnan Nuclear Power Co. Ltd.Cangnan 325800China Jiangxi Province Key Laboratory of Polymer Micro/Nano Manufacturing and Devices East China University of TechnologyNanchang 330013China School of Nuclear Science and Engineering East China University of TechnologyNanchang 330013China

To explore the kinetic adsorption under continuous and nonequilibrium states, an integration of continuous measurement and adsorption platform kinetics method was proposed, which was initially called the ICM-AP kinetics method, and a corresponding kinetic adsorption experimental method was developed. Adsorption experiments of europium(Eu) on Ca-bentonite,Na-bentonite, and the D231 cation exchange resin were performed using the ICM-AP kinetics method and continuous measurements. Because the kinetic experimental results observed in this study were different from those of traditional batch adsorption data, pseudo-first-order or pseudo-second-order kinetic models were unsuitable for fitting the experimental ***, a liquid membrane diffusion(LMD) model was developed based on the assumption of simultaneous adsorption/desorption to discuss the mechanism of kinetic adsorption. The kinetic adsorption mechanism was also studied by using *** results indicated that the proposed adsorption model can fit the experimental data more suitably, and the adsorption/desorption behaviors of Eu on bentonite and the D231 resin were simultaneously observed, suggesting that the adsorption kinetics of Eu(Ⅲ) was mainly dominated by hydrated Eu(Ⅲ) ions on the liquid membrane.

关键词： ICM-AP method LMD model Adsorption mechanism Eu(Ⅲ)