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Structure overset grid method and its applications to simulation of multi-body separation

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Science China(Physics,Mechanics & Astronomy) 2015年第9期58卷 68-75页

作者： zhang hairui FAN JingJing YUAN Wu zhang WeiHua College of Aerospace Science and Engineering National University of Defense Technology China Academy of Lanch Vehicle Technology Supercomputing Center Computer Network Information Center Chinese Academy of Sciences

This paper proposes an automatic structure overset grid method, which utilizes the hole-surface optimization with one-step searching, wall-surface grid oversetting, and dynamic overset grid approaches to achieve the high adaptability of overset grids for complex multi-body aircrafts. Specifically, based on the automatic structure overset grids, the method first solves the coupling of Navier-Stokes(N-S) unsteady flow equation and 6DOF motion equation, and establishes the multi-body collision model. Then, the numerical simulation of unsteady flow for complex aircrafts' multi-body separation, the simulation of multi-body separating trajectory and the separation safety analysis are accomplished. Thus, the method can properly handle practical engineering problems including the wing/drop tank separation, aircraft/mount separation, and cluster bomb projection. Experiments show that our numerical results match well with experimental results, which demonstrates the effectiveness of our methods in solving the multi-body separation problem for aircrafts with complex shapes.

关键词： dynamic overset grids multi-body separations CFD

Optimization of Charging/Battery-Swap Station Location of Electric Vehicles with an Improved Genetic Algorithm-Based Model

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Computer Modeling in Engineering & Sciences 2023年第2期134卷 1177-1194页

作者： Bida zhang Qiang Yan hairui zhang Lin zhang Beijing University of Posts and Telecommunications Beijing100876China PLA Army Academy of Artillery and Air Defense Zhengzhou450000China Beijing Information Science and Technology University Beijing100192China

The joint location planning of charging/battery-swap facilities for electric vehicles is a complex *** the differences between these two modes of power replenishment,we constructed a joint location-planning model to minimize construction and operation costs,user costs,and user satisfaction-related penalty *** designed an improved genetic algorithm that changes the crossover rate using the fitness value,memorizes,and transfers excellent *** addition,the present model addresses the problem of“premature convergence”in conventional genetic algorithms.A simulated example revealed that our proposed model could provide a basis for optimized location planning of charging/battery-swapping facilities at different levels under different charging modes with an improved computing *** example also proved that meeting more demand for power supply of electric vehicles does not necessarily mean increasing the sites of charging/battery-swap ***,optimizing the level and location planning of charging/battery-swap stations can maximize the investment *** proposed model can provide a reference for the government and enterprises to better plan the location of charging/battery-swap ***,it is of both theoretical and practical value.

关键词： Charging/battery-swapping facility genetic algorithm location planning excellent gene cluster

变形翼舵技术在导弹领域的应用需求及技术发展路线

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导弹与航天运载技术（中英文） 2024年第3期 9-13,28页

作者：姚重阳王晓鹏张海瑞雷豹夏艳清华大学国家卓越工程师学院北京100084 中国运载火箭技术研究院北京100076

采用变形翼舵技术可解决导弹对发射平台尺寸强约束问题,改善导弹升阻比及弹道末段机动性能,实现飞行全程气动外形最优,适应多任务作战需求。对国内外变形翼舵技术发展进行了概述,介绍了变形翼舵方案组成,分析了导弹对变形翼舵技术的需求... 详细信息

采用变形翼舵技术可解决导弹对发射平台尺寸强约束问题,改善导弹升阻比及弹道末段机动性能,实现飞行全程气动外形最优,适应多任务作战需求。对国内外变形翼舵技术发展进行了概述,介绍了变形翼舵方案组成,分析了导弹对变形翼舵技术的需求,提出了单次阶跃变形、往复伸缩变形、柔性连续变形三阶段技术发展路线以及各阶段的关键技术,为变形翼舵技术在导弹武器领域的深入研究及应用提供了参考。

关键词：变形翼舵导弹应用需求发展路线关键技术

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Experimental study on the angle of repose of pulverized coal

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Particuology 2010年第5期8卷 482-485页

作者： Wei Wang Jiansheng zhang Shi Yang Hai zhang hairui Yang Guangxi Yue Department of Thermal Engineering Tsinghua University Beijing 100084 PR China

An experimental study on the angle of repose （AoR） of pulverized coal with different particle sizes and different moisture contents （MC） was conducted. Three different measurement methods, free-base piling, fixed-base piling and sliding, were used. The data were analyzed by one-way and two-way analysis of variance. The results showed that the AoRs of pulverized coal with particle sizes smaller than 150 μm were in the range of 30-50°. The characterization of the flowability of pulverized coal was some cohesiveness or true cohesiveness. The increase of MC will increase AoR and thus decrease the flowability of the powder. However, the particle size effect is bifurcated. Below a critical size, the decrease of particle size decreases the flowability; while above the critical size, the decrease of particle size increases the flowability. It was found that the value of the critical size strongly depends on the powder density. Moreover, the AoR dependence on particle size could be linked with the Geldart＇s particle classification. The critical size at the turning point is on the boundary between Group A and Group B in Geldart＇s classification diagram. Based on the experimental results, there is no significant cross interaction between particle size and MC. The AoRs measured by free-base method and fixed-base method are close, but both remarkably smaller than that measured by the sliding method.

关键词： Angle of repose (AoR)Pulverized coalParticle sizeMoisture content

A Phase Readout Method for Wireless Passive Sensor Used in Pressure Measurement System

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Chinese Journal of Electronics 2015年第4期24卷 702-708页

作者： HONG Yingping LIANG Ting ZHENG Tingli zhang hairui LIU Wenyi XIONG Jijun Key Laboratory of Instrumentation Science & Dynamic Measurement Ministry of Education North University of China Science and Technology on Electronic Test & Measurement Laboratory North University of China

A phase difference detection method used for reading the resonant frequency through mutual coupling is designed to meet the pressure measurement in harsh environments, and a testing device of integrated modular by developing the hardware circuits is *** and discussion of the novel theoretical model in the phase readout system is presented, and a pressure test platform based on the phase difference detection is also established, which is to measure the frequency of a LC resonant sensor on the basis of 96% alumina ceramic substrate. The experimental results show that the proposed phase difference readout system presents sweep-frequency detection in the range of 1–100MHz bandwidth, and a high frequency resolution of 0.006 MHz. Sensitivity of the sensor is approximately 0.225 MHz/bar from 1 bar to 2 bar. The accuracy and functionality of the phase readout system have emphasized a wider engineering application range, so that we can make it possible that the wireless passive LC resonant sensor revolves well in practical engineering occasions outside the laboratory environment.

关键词： LC resonant sensor Resonant frequency Phase difference detection Pressure test

Generative API usage code recommendation with parameter concretization

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Science China(Information Sciences) 2019年第9期62卷 51-72页

作者： Chi CHEN Xin PENG Jun SUN Zhenchang XING Xin WANG Yifan ZHAO hairui zhang Wenyun ZHAO School of Computer Science Fudan University Shanghai Key Laboratory of Data Science Fudan University Pillar of Information System Technology and Design Singapore University of Technology and Design Research School of Computer Science Australian National University

Many programming languages and development frameworks have extensive libraries(e.g., JDK and Android libraries) that ease the task of software engineering if used effectively. With numerous library classes and sometimes intricate API(application programming interface) usage constraints, programmers often have difficulty remembering the library APIs and/or using them correctly. This study addresses this problem by developing an engine called DeepAPIRec, which automatically recommends the API usage *** to the existing proposals, our approach distinguishes itself in two ways. First, it is based on a tree-based long short-term memory(LSTM) neural network inspired by recent developments in the machinelearning community. A tree-based LSTM neural network allows us to model and reason about variable-length,preceding and succeeding code contexts, and to make precise predictions. Second, we apply data-flow analysis to generate concrete parameters for the API usage code, which not only allows us to generate complete code recommendations but also improves the accuracy of the learning results according to the tree-based LSTM neural network. Our approach has been implemented for supporting Java programs. Our experimental studies on the JDK library show that at statement-level recommendations, DeepAPIRec can achieve a top-1 accuracy of about 37% and a top-5 accuracy of about 64%, which are significantly better than the existing approaches. Our user study further confirms that DeepAPIRec can help developers to complete a segment of code faster and more accurately as compared to IntelliJ IDEA.

关键词： code recommendation API deep learning data dependency parameter concretization

基于液质联用技术结合化学计量法分析杜仲盐制前后差异性成分

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中草药 2024年第5期55卷 1518-1531页

作者：唐瑞吴杭莎李亚飞赵明方方可儿张海瑞葛卫红杜伟锋浙江中医药大学药学院浙江杭州311402 浙江中医药大学中药炮制技术研究中心浙江杭州311401 浙江中医药大学中药饮片有限公司浙江杭州311401

目的通过超高液相色谱串联三重四级杆飞行时间质谱法(UPLC-Triple-TOF-MS)对杜仲盐制前后成分进行鉴定,分析差异性成分。方法利用UPLC-Triple-TOF/MS检测杜仲中的化学成分,液相采用Waters HSS-T3色谱柱(150 mm×2.1 mm,1.8μm),以0.1%... 详细信息

目的通过超高液相色谱串联三重四级杆飞行时间质谱法(UPLC-Triple-TOF-MS)对杜仲盐制前后成分进行鉴定,分析差异性成分。方法利用UPLC-Triple-TOF/MS检测杜仲中的化学成分,液相采用Waters HSS-T3色谱柱(150 mm×2.1 mm,1.8μm),以0.1%甲酸水溶液-0.1%甲酸乙腈溶液为流动相进行梯度洗脱,体积流量为0.3 mL/min,柱温为50℃;检测波长254 nm;进样量3µL。质谱采用负离子扫描模式采集数据,根据一级准分子离子与二级碎片离子信息进行化合物的分析与鉴定。通过主成分分析(principal component analysis,PCA)和正交偏最小二乘法-判别分析(orthogonal partial least squares-discriminant analysis,OPLS-DA)对杜仲盐制前后进行差异成分分析。结果共解析出杜仲中52种成分,结合OPLSDA筛选出14个影响杜仲盐制前后质量的潜在差异性成分,分别为京尼平苷、绿原酸、杜仲醇、桃叶珊瑚苷、松脂醇二葡萄糖苷、京尼平苷酸、京尼平、eucomoside B、异绿原酸C、teuhircoside硫酸脂、橄榄素二葡萄糖苷、丁香脂素二葡萄糖苷、中脂素二葡萄糖苷和去氢二松柏醇葡萄糖苷。结论建立了杜仲盐制前后化学成分定性分析方法,筛选出盐制前后杜仲质量变化的潜在差异性成分,为杜仲盐制的增效物质基础的研究提供了科学依据,对杜仲质量控制提供更加全面的支撑。

关键词：杜仲盐制 UPLC-Triple-TOF/MS 主成分分析正交偏最小二乘法-判别分析差异性成分京尼平苷绿原酸杜仲醇桃叶珊瑚苷松脂醇二葡萄糖苷京尼平苷酸京尼平 eucomoside B 异绿原酸C teuhircoside硫酸脂橄榄素二葡萄糖苷丁香脂素二葡萄糖苷中脂素二葡萄糖苷去氢二松柏醇葡萄糖苷

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基于动态格栅的湍流风实验模拟方法研究

太阳能学报 2024年第8期45卷 587-594页

作者：金瑞麒武广兴魏永刚张海瑞李新凯刘永前华北电力大学新能源电力系统国家重点实验室北京102206 华北电力大学新能源学院北京102206 中国华能集团清洁能源技术研究院有限公司北京100031

开发一种基于动态格栅的湍流风实验模拟方法和装置,并通过调节格栅运动参数和来流风速,实现对湍流风特征参数的定量调控。实验分别研究罗斯贝数Ro、格栅雷诺数Re_(M)、格栅运动角加速度α、格栅运动周期长度T对湍流参数的影响规律。结... 详细信息

开发一种基于动态格栅的湍流风实验模拟方法和装置,并通过调节格栅运动参数和来流风速,实现对湍流风特征参数的定量调控。实验分别研究罗斯贝数Ro、格栅雷诺数Re_(M)、格栅运动角加速度α、格栅运动周期长度T对湍流参数的影响规律。结果表明,湍流参数仅对罗斯贝数敏感,平均风速与湍流度均随罗斯贝数增加而增大,而湍流积分尺度则呈现先减小后增大的趋势。综合实验工况参数,得到湍流强度可调节范围为0.05~0.39,湍流积分尺度可调节范围为0.15~1.56 m,适用于缩尺比1∶20~1∶1200范围的风电机组模型实验。

关键词：风电风洞湍流动态格栅湍流积分尺度

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多人追逃的协商微分对策最优躲避策略

航天控制 2024年第2期42卷 48-54页

作者：赵燊佳张海瑞梁卓吕瑞涂海峰中国运载火箭技术研究院北京100076

针对夺旗运动中追逃博弈的最优躲避问题,提出了一种多人追逃的协商微分对策最优躲避策略。首先,建立夺旗追逃线性化模型,并对模型进行降阶。其次,考虑能量约束和交汇时刻博弈双方距离的代价函数,构造了哈密顿函数。最后,利用Hamilton-Ja... 详细信息

针对夺旗运动中追逃博弈的最优躲避问题,提出了一种多人追逃的协商微分对策最优躲避策略。首先,建立夺旗追逃线性化模型,并对模型进行降阶。其次,考虑能量约束和交汇时刻博弈双方距离的代价函数,构造了哈密顿函数。最后,利用Hamilton-Jacobi-Isaacs(H-J-I)方程组,求解得到了协商微分对策最优躲避策略。对所设计最优躲避策略进行了“二追一”仿真和多层追捕仿真,结果表明夺旗一方的队员成功夺旗的同时能量消耗最小,验证了本文提出协商微分对策躲避策略的有效性和适用性。

关键词：飞行器制导多人追逃博弈协商微分对策夺旗