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Response to climate warming of winter wheat varieties bred across different eras in the North China Plain

Science China Earth Sciences 2024年

作者： Zhaoyang JIANG Shibo FANG Dong WU Xin LIU Huarong ZHAO Jie GUO Xinru ZHANG yongchao zhu Xuan LI Yingjie WU Dingrong WU State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences College of Resources and Environment Anhui Agricultural University Raoyang National Climate Observatory Meteorological Observation Center China Meteorological Administration Meteorological Data Center Shandong Meteorological Bureau

By the 2000s, the winter wheat regions in the North China Plain had undergone six major variety renewals. It is crucial to know how the winter wheat varieties bred across different eras respond to climate change, especially climate *** 2017 to 2022, we conducted a two-factor, two-level field experiment at Gucheng and Raoyang, with a temperature difference of 1°C existing between the two sites. The experiment used ten winter wheat varieties bred from the 1960s to the2000s and included both fertilization and no fertilization treatments. The experiment aimed to separate the effects of warming and fertilization on the growth and development of the winter wheat varieties, thereby revealing the differences in their responses to warming. All the winter wheat varieties across different eras had higher yields in warmer environments. By separating the effects of warming and fertilization, the rate of yield increase decreased with the breeding eras of varieties due to the impact of warming alone. However, it still increased with the eras due to the combined effects of warming and fertilization. For varieties from the 1980s and 2000s, there is a strong correlation between higher fertility and warmer climate adaptability. Warming has a yield gain effect, significantly amplifying the yield increase under fertilization for the middle and late varieties. Therefore, the average yield increase for varieties from the 2000s reached 67%in warmer environments. Warming has increased the average daily minimum temperature during the winter wheat growing season. It has significantly reduced the number of days below zero degrees Celsius, shortening the overwintering stage and thereby shortening the growth period of winter wheat. However, the effective developmental days (>0°C days) maintained a consistent level. Warming promotes the development of large tillers,increases leaf area and dry matter accumulation, and reduces the ratio of sterile spikelets. The varieties from the 2000s ha

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基于改进人工势场法的内河应急抢险船舶路径规划

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船舶工程 2024年第9期46卷 99-106页

作者：林威于竞宇王静峰朱勇超张琼合肥工业大学土木与水利工程学院合肥230009 安徽建工交通航务集团有限公司合肥230000

针对应急抢险船舶在极端洪涝灾害时的路径规划问题,提出一种改进人工势场法的路径规划算法,实现内河应急抢险船舶的快速精准救援。由于传统人工势场法中存在局部极小点、目标不可达等影响应急抢险船舶救援的安全问题,通过改进斥力势场... 详细信息

针对应急抢险船舶在极端洪涝灾害时的路径规划问题,提出一种改进人工势场法的路径规划算法,实现内河应急抢险船舶的快速精准救援。由于传统人工势场法中存在局部极小点、目标不可达等影响应急抢险船舶救援的安全问题,通过改进斥力势场函数解决了船舶在靠近障碍物的救援点时的目标不可达问题;引入逃逸力避免了局部极小点问题。通过数值仿真试验对比验证,改进后的人工势场法能够帮助应急抢险船舶在复杂的内河航道环境中安全到达救援点。

关键词：应急抢险船舶局部路径规划人工势场法改进斥力势场函数逃逸力

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铝-碳化硅烧结过程及其力学性能的分子动力学研究

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热加工工艺 2024年第2期53卷 126-130页

作者：朱永超李巍牛丽薇李正辉王蕾河南省高速铁路运营维护工程研究中心河南郑州451460 河南省计量科学研究院河南郑州450001

运用分子动力学方法模拟了铝-碳化硅复合体系的烧结过程,对含有不同尺寸碳化硅颗粒的烧结体进行了结构分析和拉伸测试。通过计算金属铝所占体积及其内部孔洞的体积,发现碳化硅颗粒尺寸的增加能够促进复合材料烧结后的致密程度,但过小的... 详细信息

运用分子动力学方法模拟了铝-碳化硅复合体系的烧结过程,对含有不同尺寸碳化硅颗粒的烧结体进行了结构分析和拉伸测试。通过计算金属铝所占体积及其内部孔洞的体积,发现碳化硅颗粒尺寸的增加能够促进复合材料烧结后的致密程度,但过小的增强体反而会增加孔隙率和孔洞尺寸;通过对烧结体原子结构分析和准静态拉伸,发现碳化硅颗粒尺寸的增加能够提高位错密度,但这不能带来拉伸强度的稳步提升,而烧结体的抗拉强度主要取决于其内部最大孔洞的尺寸。在本模拟尺度下,增强体与金属颗粒在尺寸相近时可以得到良好的密实效果和力学性能。

关键词：分子动力学烧结 Al-Si C复合材料力学性能

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用于冬季温室的集热器优化设计

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吉林农业大学学报 2024年第1期46卷 168-174页

作者：李亚楠陈丽梅乔凯高茹朱永超吉林农业大学工程技术学院长春130118

制作新型太阳能平板集热器,使其在我国东北冬季的平均集热效率达到40%~62%。该热量用于温室冬季采暖,选择与集热效率最相关的3个因素,即盖板类型、吸热板结构、保温层材料,进行混合型正交试验设计,并分析所选因素与试验指标间的关系。... 详细信息

制作新型太阳能平板集热器,使其在我国东北冬季的平均集热效率达到40%~62%。该热量用于温室冬季采暖,选择与集热效率最相关的3个因素,即盖板类型、吸热板结构、保温层材料,进行混合型正交试验设计,并分析所选因素与试验指标间的关系。通过极差分析得到当采用双层中空玻璃盖板加反光镜,“V”型吸热板结构及保温材料为聚乙烯板时,集热器的集热性能最好。

关键词：太阳能平板集热器温室混合型正交试验

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基于U-Net、U-Net++和Attention-U-Net网络的遥感影像水体提取

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测绘通报 2024年第8期 26-30页

作者：李振轩黄敏儿高飞陶庭叶吴兆福朱勇超合肥工业大学土木与水利工程学院安徽合肥230009

目前,深度学习在高分辨率遥感影像水体提取方面的应用已成为遥感领域的研究热点。其中基于U-Net网络的算法在水体提取中表现出较好的性能,但鲜有研究对不同U-Net网络算法在水体提取任务中的性能差异进行深入比较。因此,本文选择U-Net、U... 详细信息

目前,深度学习在高分辨率遥感影像水体提取方面的应用已成为遥感领域的研究热点。其中基于U-Net网络的算法在水体提取中表现出较好的性能,但鲜有研究对不同U-Net网络算法在水体提取任务中的性能差异进行深入比较。因此,本文选择U-Net、U-Net++和Attention-U-Net 3种卷积神经网络,基于GID数据集,进行试验与定量分析。结果表明:U-Net++的训练精度最高,其次为U-Net、Attention-U-Net,三者分别为0.912、0.907、0.899;U-Net++的边缘提取能力优于其他两种网络;在分割不同类型水体和区分遥感影像中与水体区域相似的非水体区域上,U-Net++的提取效果显著,U-Net和Attention-U-Net易出现漏提现象,效果欠佳。

关键词：水体提取高分辨率遥感影像 U-Net网络

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Mineral surface modification induced by low energy ion irradiation: Implications for solar-wind exposure effects in lunar soil

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Chinese Journal Of Geochemistry 2014年第4期33卷 351-356页

作者： zhu yongchao FU Xiaohui XU Lin ZHANG Feng ZHENG Yongchun ZOU Yongliao Key Laboratory of Lunar and Deep Space Exploration National Astronomical Observatories Chinese Academy of Sciences University of Chinese Academy of Sciences Space Science Institute Macao University of Science and Technology

We performed ion irradiation on olivine and ilmenite to simulate solar-wind exposure effects in lunar soil. The surface morphology and microstructure after ion irradiation were characterized by field emission scanning electron microscopy. Sputtering erosion significantly modified the surface of irradiated Luobusha olivine grains. All irradiated grains show smooth surface and round shape. The cleavage fractures on the unirradiated olivine surface were widened and deeply etched after He+ irradiation. Both of these are the consequence of ion sputtering erosion. There are no bubbles or voids foundin the irradiated olivine grains, because He+ dose in this study is lower than saturated fluence. Irradiated Panzhihua ilmenite grains are all covered with smooth flakes with the thickness of about 400 nm. The formation of the flakes should be related with helium bubbles and their growth during He+ implantation. Some columnar-shaped particles are found at the surface of irradiated Panzhihua ilmenite. We speculate that these particles should be sulfide because of significantly high sulfur contents.

关键词：低能离子辐照表面改性月球土壤光效果太阳风场发射扫描电子显微镜诱导矿物

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Research on the inversion of elemental abundances from Chang'E-2 X-ray spectrometry data

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Chinese Journal Of Geochemistry 2014年第3期33卷 289-299页

作者： BAN Chao ZHENG Yongchun zhu yongchao ZHANG Feng XU Lin ZOU Yongliao National Astronomical Observatories Chinese Academy of Sciences University of Chinese Academy of Sciences Space Science Institute Macao University of Science and Technology

The elemental abundances of lunar surface are the important clues to study the formation and evolution history of the Moon. In 2010, China's Chang'E-2(CE-2) lunar orbiter carried a set of X-ray spectrometer(XRS) to investigate the elemental abundances of the lunar surface. During CE-2's life span around the Moon, the XRS experienced several events of solar flare. The X-ray solar monitor onboard recorded the spectra of solar X-rays at the same time. In this paper, we introduced the XRS instrument and data product. We analyzed the characteristics of the XRS data. Using the data obtained during an M solar flare event which had occurred on Feb. 16, 2011, we derived the elemental abundances of Mg, Al, Si, Ca and Fe of the lunar surface in the Oceanus Procellarum. Finally, we discussed the factors that influence the accuracy of the inversion.

关键词： X射线光谱元素丰度数据反演月球表面太阳耀斑月球探测器演化历史数据产品

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The ellipsoidal corrections for boundary value problems of deflection of the vertical with ellipsoid boundary

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Geodesy and Geodynamics 2017年第4期8卷 292-296页

作者： Xiangchao Meng Jinhai Yu yongchao zhu Key Laboratory of Computational Geodynamics Chinese Academy of SciencesBeijing 100049 China College of Earth Science University of Chinese Academy of Sciences Beijing 100049 China Beijing Key Laboratory of Urban Spatial Information Engineering Beijing 100038 China

The boundary value problem of deflections of vertical with ellipsoid boundary is studied in the paper. Based on spherical harmonic series, the ellipsoidal corrections for the boundary value problem are derived so that it can be well solved. In addition, an imitation arithmetic is given for examining the accuracies of solutions for the boundary value problem as well as its spherical approximation problem, and the computational results illustrate that the boundary value problem has higher accuracy than its spherical approximation problem if deflection of the vertical are measured on geoid.

关键词： Disturbing potential Deflection of the vertical Ellipsoid Ellipsoidal correction

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呼伦贝尔草原生长季叶绿素荧光的特征及其对气象条件变化的响应

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大气科学学报 2024年第4期47卷 643-652页

作者：张静吴东丽刘达新刘聪朱永超张全军杨大生张世豪金磊中国气象局气象探测中心北京100081 北京象元气象观测技术研究院北京100081 内蒙古自治区鄂温克族自治旗气象局内蒙古鄂温克021100

在2022年生长季内,基于轨道植被观测仪(型号NZD-G1)对呼伦贝尔草原开展了日光诱导叶绿素荧光(Solar-Induce chlorophyll Fluorescence, SIF)的原位观测。相较于归一化植被指数,SIF的低频变化分量同样可以表征植物在生长季内的长势变化,... 详细信息

在2022年生长季内,基于轨道植被观测仪(型号NZD-G1)对呼伦贝尔草原开展了日光诱导叶绿素荧光(Solar-Induce chlorophyll Fluorescence, SIF)的原位观测。相较于归一化植被指数,SIF的低频变化分量同样可以表征植物在生长季内的长势变化,而高频变化可以更清楚地监测植物内光合作用的生理过程,且其高频变化与气象条件密切相关。土壤水含量和SIF的关系是非线性的,当降水持续偏多导致土壤偏涝时,牧草的生理代谢减弱,光合作用减缓(SIF值偏低);当前期降水适量导致土壤湿润,且太阳辐射较强时,SIF值可以持续稳定在较高水平,植物光合作用旺盛,长势良好。而在生长季后期,偏凉的秋雨会显著降低植物的光合作用,且后期难以恢复。

关键词：生态系统光合作用叶绿素荧光降雨土壤水含量

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Influence of misting system on the thermal environment and thermal comfort of seated people in semi-outdoor space in Xi’an,China

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Frontiers of Architectural Research 2024年第3期13卷 668-681页

作者： Xu Xie Zhen Sun Xi zhu Shengkai Zhao Zun Wang yongchao Zhai College of Architecture Xi’an University of Architecture and TechnologyXi’an 710055China State Key Laboratory of Green Building Xi’an University of Architecture and TechnologyXi’an 710055China

In summer,factors such as solar radiation could make semi-outdoor spaces uncomfortable,and the use of misting systems for evaporative cooling is a low-energy improvement *** investigate the impact of misting system on the thermal environment and thermal comfort of seated people improvement,a field study was conducted at a semi-outdoor cafeteria in Xi’*** results indicated that the misting system was capable of reducing the ambient air temperature by 2.4-4.9℃and increasing the relative humidity by 17.1%-17.8%.Participants in misting condition reported lower thermal sensation and higher thermal acceptability,thermal preference,humidity sensation,humidity preference and humidity *** no misting condition,the upper SET*limit acceptable to 80%of the population was 28.5℃.However,in the misting condition,the acceptable percentage of participants in each SET)interval was more than 90%.When SET)was 22.1-23.7℃,the improvement in human thermal comfort through misting system was not *** SET)was 23.7-28.5℃,the misting system significantly improve human thermal ***,two control temperature thresholds of the misting system were provided according to the relationship between 80%,the maximum(89.3%)acceptable percentage and the air temperature,which were 30.1℃and 26.5℃,respectively.

关键词： Misting system Thermal environment Thermal response Acceptable temperature Control strategy

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