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一种星载激光测高仪光斑内定位方法

武汉大学学报（信息科学版） 2019年第4期44卷 586-592页

作者：岳春宇孙世君何红艳北京空间机电研究所北京100094 先进光学遥感技术北京市重点实验室北京100094 清华大学精密仪器与机械学系北京100084

提出一种利用铅垂线轨迹法及高程结构信息约束的星载激光测高仪光斑内定位方法。在星载激光测高仪辅助立体摄影测量体制下,以激光回波中包含的高精度高程结构信息作为约束条件,在足印光斑内,配合立体图像匹配生成的数字高程模型,选取定... 详细信息

提出一种利用铅垂线轨迹法及高程结构信息约束的星载激光测高仪光斑内定位方法。在星载激光测高仪辅助立体摄影测量体制下,以激光回波中包含的高精度高程结构信息作为约束条件,在足印光斑内,配合立体图像匹配生成的数字高程模型,选取定位候选点,并通过铅垂线轨迹法优化定位候选点高程值,消除立体图像定位误差引起的高程误差,获取符合高程结构约束的一系列位置的三维坐标。试验结果表明,该方法能够实现大光斑星载激光测高仪足印内的定位,高程定位精度为0.16 m,平面定位精度与立体图像一致。

关键词：星载激光测高仪全波形数据铅垂线轨迹法几何定位高程结构

Parallel Study on Potential and Existing Geographical Distribution of Haloxylon Dominated Desert Vegetation in China

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Chinese Forestry Science and Technology 2006年第2期5卷 46-53页

作者： GUO Quanshui WANG Chunling TAN Deyuan MA Chao WANG Xiangfu HAO Jianxi he hongyan Research Institute of Forest Ecology and Protection Chinese Academy of Forestry Key Laboratory of Forest Ecology and Environment State Forestry Administration Beijing 100091 P. R. China Department of Wildlife Protection State Forestry Administration Beijing 100043 P. R. China College of Bioscience and Biotechnology Beijing Forestry University Beijing 100083 P. R. China Inner Mongolia Forestry Industrial Co. Ltd. Yakeshi 022150 P. R. China

By applying ARC/INFO (NT version) of the GIS software package , we extracted the existing geographicaldistribution ofHaloxylon dominated desertvegetationandproduced athematicmap ofgeographical distribution of theexisting Haloxylon dominated desert vegetation based on the newly published Vegetation Atlas of China;we defined the adaptiveparameter range ofgeographical and climate ofHaloxylon dominated desert vegetation to generate the potential geographical distribution map of Haloxylon dominated desert vegetation with thesupport of GREEN software. We then sliced and compared the existing and thepotential distribution maps. The results show that the potential geographical distribution areas of Haloxylon ammodendron and Haloxylon persicum dominated desert vegetation accord with the existing distribution areas in the administration division, and the topographic types in both the distribution areas are similar. However, the borders of different directions ofthe potential H. ammodendron dominated desert vegetation distribution has surpassed 0.4° to 5.9° of the existing borders. The borders of different directions of the potential H. persicum dominated desert vegetation has surpassed 0.9° to 3.3° of the existing borders. In China, the existing geographical distributionalarea ofH. ammodendron dominated desertvegetation accounts for 9.1% of the potential one in China and the proportion of the existing H. persicum dominated desert vegetation distribution area to the potential areais 34.1%. The result of comparison of the potential and the existing distribution areaof Haloxylon dominated desert vegetation can provide important scientific basisfor the recovery, reconstruction and introduction of Haloxylon dominated desertvegetation.

关键词： Haloxylon ammodendron Haloxylon persicum desert vegetation existent distribution potential distribution

Dynamic Coupling Analysis of Semisubmersible Platform Float-over Method for Docking Case

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Journal of Ocean University of China 2024年第2期23卷 345-357页

作者： DING hongyan QIN Licheng ZHANG Puyang SONG Zhengrong XIE Weiwei State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China Offshore Oil Engineering Co. Ltd.Tianjin 300461China

In this paper,the multi-body coupled dynamic characteristics of a semisubmersible platform and an HYSY 229 barge were ***,coupled hydrodynamic analysis of the HYSY 229 barge and the semisubmersible platform was *** hydrodynamic parameters were obtained using the retardation function method of three-dimensional frequency-domain potential flow *** results of the hydrodynamic analysis were highly consistent with the test findings,verifying the accuracy of the multifloating hydrodynamic coupling analysis,and key hydrodynamic parameters were solved for different water depths and the coupling *** to the obtained results,the hydrodynamic influence was the largest in shallow waters when the coupling effect was ***,the coupled motion equation combined with viscous damping,fender system,and mooring system was established,and the hydrodynamics,floating body motion,and dynamic response of the fender system were *** analysis revealed good agreement among the surge,sway,and yaw motions of the two floating ***,when the wave period reached 10 s,the motion of the two floating bodies showed severe shock,and a relative motion was also ***,excessive constraints should be added between the two floating bodies during construction to ensure construction *** numerical analysis and model test results of the semisubmersible platform and HYSY 229 barge at a water depth of 42 m and sea conditions of 0°,45°,and 90° were in good agreement,and the error was less than 5%.The maximum movement of the HYSY 229 barge reached 2.61 m in the sway direction,whereas that of the semisubmersible platform was 2.11 *** construction,excessive constraints should be added between the two floating bodies to limit their relative movement and ensure construction safety.

关键词： float-over method semisubmersible platform coupling hydrodynamic fender system time-domain analysis

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大数据视角下供应链与组织绩效预测

商业经济研究 2019年第9期 29-31页

作者：贺红燕河北政法职业学院副教授石家庄050000

大数据系统的应用有效提升了供应链管理中对于信息资源的处理水平,供应链的组织绩效也呈现较为明显的提升态势,大数据是破解供应链质量管理系统中"组织黑箱"的核心切入点。本文从大数据技术的主要作用方向出发,分析大数据系统对供应链... 详细信息

大数据系统的应用有效提升了供应链管理中对于信息资源的处理水平,供应链的组织绩效也呈现较为明显的提升态势,大数据是破解供应链质量管理系统中"组织黑箱"的核心切入点。本文从大数据技术的主要作用方向出发,分析大数据系统对供应链企业信息聚合能力和信息萃取水平的影响,采用李克特五点量表对供应链绩效进行测量,通过实证检验证明信息聚合能力与信息萃取水平对供应链绩效产生了显著正向影响,最后根据研究内容提出了对应的理论贡献及实践意义。

关键词：大数据供应链管理信息萃取组织绩效

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“高分四号”卫星观测能力与应用前景分析

航天返回与遥感 2017年第1期38卷 98-106页

作者：王殿中何红艳北京空间机电研究所北京100094

"高分四号"卫星是中国高分辨率对地观测系统重大专项工程中首颗地球同步轨道遥感卫星,也是目前世界上地球同步轨道上第一颗高分辨率遥感卫星,它具有较高空间分辨率、极高时间分辨率、多种谱段选择、广阔的观测范围等特点。为使"高分四号... 详细信息

"高分四号"卫星是中国高分辨率对地观测系统重大专项工程中首颗地球同步轨道遥感卫星,也是目前世界上地球同步轨道上第一颗高分辨率遥感卫星,它具有较高空间分辨率、极高时间分辨率、多种谱段选择、广阔的观测范围等特点。为使"高分四号"卫星充分发挥观测能力,成为灾害监测以及防灾减灾的有效工具,文章对应典型遥感应用,总结归纳出了五种观测模式,分别是凝视模式、跟踪模式、巡航模式、签到模式、夜间模式,并分析给出各种模式下相应的观测策略。文中还以现有国产遥感卫星为例,讨论了影响"高分四号"卫星应用的两种重要因素,即数据连续性和数据稳定性,其中针对巡航模式对数据连续性的潜在影响提出了"高分四号"卫星在轨使用建议,针对数据稳定性提出了一种评价模型。该文对于有关方面应对多种观测需求、合理使用"高分四号"卫星在轨观测能力具有一定参考价值。

关键词： “高分四号”卫星观测能力地球同步轨道高分辨率航天遥感

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一种新的遥感影像清晰度评价方法

中国空间科学技术 2016年第2期36卷 50-57页

作者：谭伟杨秉新何红艳北京空间机电研究所北京100094

针对传统清晰度评价算法很难准确评价遥感卫星影像清晰度的问题,结合工程应用及遥感影像特点提出了一种新的遥感图像清晰度评价算法——自检测灰度梯度函数清晰度评价算法。把评价过程分为目标区域检测和清晰度特征参量提取,为解决遥感... 详细信息

针对传统清晰度评价算法很难准确评价遥感卫星影像清晰度的问题,结合工程应用及遥感影像特点提出了一种新的遥感图像清晰度评价算法——自检测灰度梯度函数清晰度评价算法。把评价过程分为目标区域检测和清晰度特征参量提取,为解决遥感影像数据量大且景物密度与分布特点各异的问题,首先通过检测算子对一幅遥感影像中各区域进行检测来得到景物丰富且边缘明显的目标区域,然后再对目标区域进行灰度预处理并提取目标区域的边缘灰度梯度来评价清晰度。通过三组不同类型影像对该算法进行验证,分别为遥感相机在轨离焦仿真影像和噪声仿真影像,以及在轨型号遥感卫星影像,对比几种传统典型清晰度评价算法和自检测灰度梯度函数的评价效能,结果表明:文中方法满足遥感影像清晰度评价的基本要求,解决了传统算法无法横向比较不同遥感相机影像及不同大小影像清晰度的问题,是一种适合卫星遥感影像清晰度评价的方法。

关键词：清晰度目标区域特征参量预处理影像评估航天遥感

The Influence of Significant Public health Events on Offline Consumption and Its Pathways

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Journal of Systems Science and Systems Engineering 2024年第5期33卷 627-648页

作者： Baile Lu Kewei Zhou Shuai Hao La Ta hongyan Dai Weihua Zhou College of Systems Engineering National University of Defense TechnologyChangsha 410073China Business School Central University of Finance and EconomicsBeijing 100081China Department of Marketing and Operations Management College of BusinessSouthern University of Science and TechnologyShenzhen 518055China School of Management Zhejiang UniversityHangzhou 310058China

In the face of a significant public health event,consumers may either increase their panic buying or decrease their willingness to make *** study focuses on the impact of a significant public health event on offline store sales and consumer consumption,utilizing data from chain convenience stores in hefei and Wuhu during early 2019 and early 2020 in *** a difference-in-differences model,the study investigates the effect of the significant public health event outbreak on weekly store sales,order numbers,and consumer consumption in terms of product quantities,transaction amount,average amount per order,and transaction *** from prior literature that finds hoarding behavior of consumers online,the findings of this paper indicate a significant reduction in stores’offline weekly sales and order numbers,as well as consumers’offline weekly consumption across the four dimensions,as a result of the significant public health event ***,employing a mediation model,the study explores the pathway of population mobility through which the significant public health event adversely affects offline ***,subset analysis is conducted for stores located in different areas and consumers with varying characteristics,revealing that the aforementioned conclusions predominantly apply to stores situated in office areas and residential areas,as well as consumers with either no apparent preference for different product categories or a noticeable preference for food.

关键词： Significant public health event offline consumption population mobility mediating effect

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一种基于量子力学的遥感图像滤波方法研究

红外与激光工程 2016年第A02期45卷 140-144页

作者：张智林栩凌何红艳北京空间机电研究所北京100094 南京理工大学计算机科学与技术学院江苏南京210094

提出了一种基于量子空间的光学遥感图像滤波方法。根据量子力学特性,对量子遥感成像建模。首先进行平移不变小波变换后将图像信息分层,将图像信息转换为量子叠加态信息,然后将图像信息转换成不同量子面,在每个量子面下依据量子计算理论... 详细信息

提出了一种基于量子空间的光学遥感图像滤波方法。根据量子力学特性,对量子遥感成像建模。首先进行平移不变小波变换后将图像信息分层,将图像信息转换为量子叠加态信息,然后将图像信息转换成不同量子面,在每个量子面下依据量子计算理论进行信息的范数优化约束。之后将所有优化后的各个面上的量子信息转换为图像信息,最后进行信息重构。实验证明这种方法能够有效提高图像的质量,图像评价指标均有所提高。与传统滤波方法相比,该方法能够更加有效地对遥感图像进行滤波。

关键词：量子滤波图像处理遥感量子比特

Trends and Age-Period-Cohort Effect on Incidence of Varicella Under Age 35—China,2005-2021

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China CDC weekly 2024年第18期6卷 390-395,I0005页

作者： Guijie Luan hongyan Yao Dapeng Yin Jianjun Liu Department of Education and Training Chinese center for Disease Control and PreventionBeijingChina Hainan Provincial Center for Disease Control and Prevention Haikou CityHainan ProvinceChina Chinese center for Disease Control and Prevention BeijingChina

Summary What is already known about this topic?Varicella is an acute respiratory infectious disease primarily affecting ***,recent studies have indicated an increasing susceptibility to varicella among older age *** is added by this report?The findings demonstrate a significant rise in the incidence rate among individuals aged *** under 20 years old were found to have a higher risk compared to females,whereas males had a lower risk compared to females aged 20-35 years.

关键词： acute respiratory Incidence