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基于机载组合导航数据的雷达探测效能评估方法研究

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弹箭与制导学报 2020年第6期40卷 106-110页

作者：徐琳白瑞阳中国航空研究院北京100029 95910部队甘肃酒泉735018

针对机载雷达探测精度评估过程中数据精度不高、组织实施不便等情况,提出了一种基于惯卫组合导航数据的雷达探测误差测算方法,首先利用坐标系转换将组合导航数据和雷达探测数据统一至同一坐标系下,然后进行统一时空基准下的误差对比分析... 详细信息

针对机载雷达探测精度评估过程中数据精度不高、组织实施不便等情况,提出了一种基于惯卫组合导航数据的雷达探测误差测算方法,首先利用坐标系转换将组合导航数据和雷达探测数据统一至同一坐标系下,然后进行统一时空基准下的误差对比分析,最后在误差分析的基础上,探究速度、高度等因素对雷达探测误差的影响规律。半实物仿真数据表明,文中所提的方法可利用日常训练数据对雷达探测效能进行综合分析,可操作性强,具有一定的参考意义和实用价值。

关键词：组合惯导雷达探测效能规律分析

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Gabor变换在仿真模型验证中的应用

弹箭与制导学报 2014年第4期34卷 187-188,195页

作者：白瑞阳吴晓燕张玉新姚春明空军工程大学防空反导学院西安710051

仿真模型验证是从模型预期使用的角度出发,确定模型和有关数据代表真实世界正确程度的过程,是VV&A工作的重要内容之一。针对传统验证方法不能将仿真数据和试验数据的时频域特性结合起来综合分析的特点,从时频联合分析的思想出发,将Gabo... 详细信息

仿真模型验证是从模型预期使用的角度出发,确定模型和有关数据代表真实世界正确程度的过程,是VV&A工作的重要内容之一。针对传统验证方法不能将仿真数据和试验数据的时频域特性结合起来综合分析的特点,从时频联合分析的思想出发,将Gabor变换引入仿真模型验证中,实现了对仿真数据和试验数据时频域的综合分析。实例分析表明,该方法可以提高模型验证的准确性,具有一定的实用性。

关键词： Gabor变换模型验证 CLIMB方案

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质量矩拦截弹变质心执行机构运动分析

弹箭与制导学报 2015年第3期35卷 47-49,92页

作者：姚春明李小兵吴博文白瑞阳空军工程大学防空反导学院西安710051

质量矩拦截弹通过驱动变质心执行机构改变导弹质心,进而改变其姿态角,从而实现对拦截弹的机动控制。文中从质量矩拦截弹的动力学问题入手,建立了非线性动力学模型,并对变质心执行机构运动情况进行了理论分析及仿真研究,分析研究了引入... 详细信息

质量矩拦截弹通过驱动变质心执行机构改变导弹质心,进而改变其姿态角,从而实现对拦截弹的机动控制。文中从质量矩拦截弹的动力学问题入手,建立了非线性动力学模型,并对变质心执行机构运动情况进行了理论分析及仿真研究,分析研究了引入变质心执行机构对拦截弹带来的转动惯量、力矩和状态耦合的影响情况,对影响拦截弹快速响应以及耦合特性的主要因素进行了分析,并进行仿真验证,为研究质量矩拦截弹的控制律和实际应用打下基础。

关键词：质量矩拦截弹执行机构运动分析

Degradation behaviors of Nabumetone and its metabolite during UV/monochloramine process:Experimental and theoretical study

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Journal of Environmental Sciences 2024年第8期142卷 103-114页

作者： Xiang Tu Yunsong bai Qing Fu Sheng Chang Kunfeng Zhang Yang Pan ruiyang Xiao Yifu Fu Qi Zhang State Key Laboratory of Environmental Criteria and Risk Assessment State Environmental Protection Key Laboratory of Drinking Water Source ProtectionResearch Centre of Lake EnvironmentNational Engineering Laboratory for Lake Pollution Control and Ecological RestorationChinese Research Academy of Environmental SciencesBeijing 100012China School of Environmental Science and Engineering Suzhou University of Science and TechnologySuzhou 215009China Institute of Environmental Engineering School of Metallurgy and EnvironmentCentral South UniversityChangsha 410083China School of Forestry Northeast Forestry UniversityHarbin 150040China

This study investigated degradation behaviors of a nonsteroidal anti-inflammatory drug Nabumetone(NMT)and its major metabolite 6-methoxy-2-naphthylacetic acid(MNA)in the coupling process of ultraviolet and monochloramine(UV/NH2Cl).The second-order rate constants of the contaminants reacting with reactive radicals(HO·,Cl·,Cl_(2)·-,and CO_(3)·^(-))were determined by laser flash photolysis ***·and Cl·contributed predominantly with 52.3%and 21.7%for NMT degradation and 60.8%and 22.3%for MNA *** presence of chlorides retarded the degradation of NMT,while promoted the destruction of MNA,which was ascribed to the photosensitization effects of MNA under UV *** functional theory(DFT)calculations revealed that radical adduct formation(RAF)was dominant pathway for both HO·and Cl·reacting with the contaminants,and hydrogen atom transfer(HAT)preferred to occur on side chains of NMT and *** reacted with NO_(2)·through single electron transfer(SET)with the second-order rate constant calculated to be 5.35×10^(7)(mol/L)^(-1)sec^(-1),and the contribution of NO_(2)·was predicted to be 13.0%of the total rate constant of NMT in pure water,which indicated that NO_(2)·played a nonnegligible role in the degradation of *** acute toxicity and developmental toxicity of NMT were enhanced after UV/NH_(2)Cl treatment,while those of MNA were *** transformation products of both NMT and MNA exhibited higher mutagenicity than their parent *** study provides a deep understanding of the mechanism of radical degradation of NMT and MNA in the treatment of UV/NH2Cl.

关键词： UV/NH_(2)Cl Reactive species Degradation kinetics Reaction mechanism Degradation products

COVID-19 transmission driven by age-group mathematical model in Shijiazhuang City of China

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Infectious Disease Modelling 2023年第4期8卷 1050-1062页

作者： Fengying Wei ruiyang Zhou Zhen Jin Senzhong Huang Zhihang Peng Jinjie Wang Ximing Xu Xinyan Zhang Jun Xu Yao bai Xiaoli Wang Bulai Lu Zhaojun Wang Jianguo Xu School of Mathematics and Statistics Fuzhou UniversityFuzhou350116FujianChina Center for Applied Mathematics of Fujian Province Fuzhou UniversityFuzhou350116FujianChina Key Laboratory of Operations Research and Control of Universities in Fujian Fuzhou UniversityFuzhou350116FujianChina Complex Systems Research Center Shanxi UniversityTaiyuan030006ShanxiChina School of Statistics and Data Science ZhiYing Research Center for Health DataNankai University300071TianjinChina Department of Biostatistics School of Public HealthNanjing Medical UniversityNanjing211166JiangsuChina Nankai Institute of Economics Binhai Development InstituteNankai UniversityTianjin300071China Children's Hospital of Chongqing Medical University Chongqing400010China Jinzhou Center for Disease Control and Prevention Jinzhou121000LiaoningChina School of Statistics and Data Science Nankai UniversityTianjin300071China Xi'an Center for Disease Control and Prevention Xi'an710061ShaanxiChina Beijing Center for Disease Control and Prevention Beijing100013China Suzhou Center for Disease Control and Prevention Suzhou215004JiangsuChina State Key Laboratory of Communicable Disease Prevention and Control National Institute for Communicable Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing102206China Institute of Public Health Nankai UniversityTianjin300071China

Background:A COVID-19 outbreak in the rural areas of Shijiazhuang City was attributed to the complex interactions among vaccination,host,and non-pharmaceutical interventions(NPIs).Herein,we investigated the epidemiological characteristics of all reported symptomatic cases by picking Shijiazhuang City,Hebei Province in Northern China as research *** addition,we established an age-group mathematical model to perform the optimal fitting and to investigate the dynamical profiles under three ***:All reported symptomatic cases of Shijiazhuang epidemic(January 2-February 3,2021)were investigated in our *** cases were classified by gender,age group and location,the distributions were analyzed by epidemiological ***,the reported data from Health Commission of Hebei Province was also analyzed by using an age-group mathematical model by two phases and three ***:Shijiazhuang epidemic caused by SARS-CoV-2 wild strain was recorded with the peak 84 cases out of 868 reported symptomatic cases on January 11,2021,which was implemented with strong NPIs by local government and referred as baseline situation in this *** research results showed that R0 under baseline situation ranged from 4.47 to 7.72,and Rt of Gaocheng Distinct took 3.72 with 95%confidence interval from 3.23 to 4.35 on January 9,the declining tendencies of Rt under baseline situation were kept till February 3,the value of Rt reached below 1 on January 19 and remained low value up to February 3 for Gaocheng District and Shijiazhuang City during Shijiazhuang *** indicated Shijiazhuang epidemic was under control on January ***,if the strong NPIs were kept,but remote isolation operated on January 11 was not implemented as of February 9,then the scale of Shijiazhuang epidemic reached 9,482 cases from age group who were 60 years old and over out of 31,017 symptomatic *** investigation also revealed that Shijiazhuang epidemic reache

关键词： COVID-19 Wild strain Non-pharmaceutical interventions Shijiazhuang epidemic Transmission dynamics

Inversion of Canopy Nitrogen Content in Apple Orchard Based on GF-1 Satellite Image

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遥感科学（中英文版） 2019年第1期7卷 27-38页

作者： Shujing Cao Xicun Zhu Jingling Xiong ruiyang Yu Xueyuan bai uanmao Jiang Dongsheng Gao Guijun Yang College of Resources and Environment Shandong Agricultural University Tai'an 271018 China Key Laboratory of Agricultural Ecology and Environment Shandong Agricultural University Tai'an 271018 China College of Horticulture Science and Engineering Shandong Agricultural University National Apple Engineering and Technology Research Center Tai'an 271018 China National Engineering Research Center for Information Technology in Agriculture Beijing 100097 China

The apple orchard in Qixia City, Yantai City, Shandong Province was used as the research area. The nitrogen content inversion of apple canopy was studied by using the satellite remote sensing images of GF-1. On the basis of GF-1 satellite multispectral image preprocessing, vegetation index was extracted by band math. The nitrogen sensitive vegetation index of apple canopy was selected by correlation analysis of nitrogen content in apple canopy. The best inversion model for the nitrogen content of apple canopy was selected by establishing the regression model of univariate and multivariate factors. The nitrogen content of the canopy of apple orchard in the study area was inverted in space. The results showed that the 6 vegetation indices of RVI, NDVI, EVI, VARI, NPCI and NRI were better correlated with nitrogen content in the vegetation index based on GF-1 satellite multispectral imaging. The best inversion model of nitrogen content in apple canopy layer is the multivariate stepwise regression (MSR) model: Nc = 35.74– 41.978^*NPCI-10.78^*NDVI. The R^2 and RMSE of the model was 0.69 and 1.07. The spatial inversion of nitrogen content in apple orchard canopy was obtained. This study provided theoretical basis and technical support for large-area rapid monitoring of regional fruit tree nutrients.

关键词： GF-1 Nitrogen Content Inversion Apple Tree Canopy

Simulated Reflectance of Apple Trees in Canopy Level Based on the PROSAIL Model and HJ-1A-HSI Data

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遥感科学（中英文版） 2019年第1期7卷 18-26页

作者： Xiaoyan Guo Xicun Zhu Jingling Xiong ruiyang Yu Xueyuan bai Yuanmao Jiang Dongsheng Gao Guijun Yang College of Resources and Environment Shandong Agricultural University Tai’an 271018 China Key Laboratory of Agricultural Ecology and Environment Shandong Agricultural University Tai’an 271018 China College of Horticulture Science and Engineering Shandong Agricultural University National Apple Engineering and Technology Research Center Tai’an 271018 China National Engineering Research Center for Information Technology in Agriculture Beijing 100097 China

Using the PROSAIL radiation transfer model and HJ-1A-HSI data to simulate the canopy reflectivity of apple trees, this study lays the foundation for the inversion of canopy parameters. Taking Qixia City of Yantai City, Shandong Province as the research area, the apple tree was taken as the research object, and the hyperspectral reflectance, LAI and sample GPS of apple canopy were measured in the field. The parameters required for the PROSAIL model were obtained by experimental methods. The model simulates the reflectivity;the HSI image data is preprocessed, and the canopy reflectivity is extracted by GPS coordinates. The PROSAIL model and the HSI image simulated reflectance were fitted to the measured apple canopy reflectivity. The decisive factor (R2) of the simulated reflectance and the measured reflectance of the PROSAIL model was 0.9944, and the relative error (RE%)was 0.1845. The HSI data simulated reflectance and measured reflectance. The coefficient of determination is 0.9714 and the relative error is 0.6202. Both have achieved good fitting effects and can be used for inversion studies of apple canopy parameters.

关键词： Apple Tree PROSAIL Model HJ-1A-HSI Canopy Reflectivity

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生物质快速热解流化床反应器气力进料特性

化工进展 2022年第4期41卷 1742-1749页

作者：许瑞阳白勇司慧刘德财祁项超北京林业大学工学院北京100083 河北省活性炭产业技术研究院河北承德067500

为探究不同工况下热解流化床反应器的气力进料特性,设计并搭建了流化床反应器气力进料冷态试验装置。生物质原料和床料分别采用落叶松颗粒和石英砂颗粒,通过试验测得了本装置的最小流化速度,研究了流化气速、喷动气速、流量比、初始静... 详细信息

为探究不同工况下热解流化床反应器的气力进料特性,设计并搭建了流化床反应器气力进料冷态试验装置。生物质原料和床料分别采用落叶松颗粒和石英砂颗粒,通过试验测得了本装置的最小流化速度,研究了流化气速、喷动气速、流量比、初始静床高、石英砂粒径、落叶松粒径对流化床反应器气力进料特性的影响。试验结果表明:流化气速和喷动气速的增加均会提高进料率;流化气使床料流化并为落叶松颗粒提供进料空间,喷动气为落叶松颗粒提供动能,并平衡一部分床层压力;落叶松与石英砂粒径的增加对进料效果不利;流量比在1.9~2.7范围内进料率高且稳定性好。本文构建了生物质、床料与气体的三相流物理及数学模型,开展试验对模型进行验证,结果表明其预测误差为±13%。

关键词：生物质快速热解流化床气力输送模型

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光致相变型偶氮苯基共聚物的制备及在可逆胶黏剂领域的应用

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高分子材料科学与工程 2023年第9期39卷 144-149页

作者：陈隆旋公丕文穆家慧赵瑞阳白佳玉青岛科技大学化工学院山东青岛266000 沈阳医学院辽宁沈阳110034

光致可逆胶黏剂的设计和开发,在一定程度上解决了传统胶黏剂在分离、回收和修复粘接表面等方面存在的问题。文中设计并合成了一种具有光致相态转换性能的偶氮苯基共聚物(PNY-Azo),其反式构象(固态)和顺式构象(液态)在黏附强度上表现出... 详细信息

光致可逆胶黏剂的设计和开发,在一定程度上解决了传统胶黏剂在分离、回收和修复粘接表面等方面存在的问题。文中设计并合成了一种具有光致相态转换性能的偶氮苯基共聚物(PNY-Azo),其反式构象(固态)和顺式构象(液态)在黏附强度上表现出较大差异,实现了对黏附基材的光控黏附和剥离,可应用于制备光致可逆胶黏剂。通过在共聚物侧链上增加氧原子数量,以此增强了共聚物分子链间的超分子作用(氢键作用)以及共聚物的链间缠结性能,从而有效地提高了PNY-Azo的黏结强度,其反式构象状态下黏结强度最高可达4.59 MPa。

关键词：光响应材料偶氮苯基共聚物固-液转换可逆胶黏剂黏结强度