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The Crop Journal 2024年第4期12卷 1233-1241页

作者： Na Zhao xiquan wang Jun Ma Xiaohong Li Jufeng Cao Jie Zhou Linmei Wu Peiyi Zhao Weidong Cao Bayannur Academy of Agricultural and Animal Sciences Linhe 015400Inner MongoliaChina College of Agronomy Inner Mongolia Agricultural UniversityHohhot 010019Inner MongoliaChina College of Agriculture Nanjing Agricultural UniversityNanjing 210095JiangsuChina Inner Mongolia Academy of Agricultural&Animal Husbandry Sciences Hohhot 010031Inner MongoliaChina State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China/Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural SciencesBeijing 100081China

In a nine-year field experiment in a wheat-maize-sunflower cropping system in Hetao Irrigation Area,Inner Mongolia,China,organic amendments applied as straw,manure,green manure,and the combination of green manure and straw increased wheat and maize yield,soil aggregate stability,and soil microbial activity in comparison with chemical fertilizer,without changing greenhouse gas emission intensity.

关键词： Green manure Straw Manure Soil organic carbon Soil quality Crop production Diversified cropping

基于空间三维欧拉角估计的靶场外弹道数据处理方法研究

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兵器装备工程学报 2024年第4期45卷 75-81页

作者：杨雪林王西泉张旭斌张见升董斌王艳中国兵器工业试验测试研究院陕西华阴714200

针对雷达测试远程飞行试验获取的外弹道数据在转换至炮位发射坐标系过程中,事后数据处理结果落点距离偏差较大的问题,提出了一种基于空间三维欧拉角的弹道数据处理方法,该方法估计雷达发射坐标系旋转至炮位发射坐标系的空间三维欧拉角,... 详细信息

针对雷达测试远程飞行试验获取的外弹道数据在转换至炮位发射坐标系过程中,事后数据处理结果落点距离偏差较大的问题,提出了一种基于空间三维欧拉角的弹道数据处理方法,该方法估计雷达发射坐标系旋转至炮位发射坐标系的空间三维欧拉角,对雷达发射坐标系进行三轴方向的旋转,使其与炮位发射坐标系三轴指向在空间上方向一致,然后再进行坐标系平移,得到包含地球曲率因素的炮位发射坐标系数据处理结果。将该弹道数据处理方法得到的弹道落点,以及传统平移处理方法得到的弹道落点与真实落点的距离偏差分布情况进行对比分析,结果表明:基于空间三维欧拉角的数据处理落点偏差更小,落点数据精度更高,平均偏差缩小百分比达48.9%。本研究对于弹体的寻找、销毁与回收具有十分重要意义。

关键词：地球曲率欧拉角弹道数据处理坐标系旋转

Effect of urbanization on the winter precipitation distribution in Beijing area

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Science China Earth Sciences 2009年第2期52卷 250-256页

作者： wang xiquan wang ZiFa QI YanBin GUO Hu Nansen-Zhu International Research Center Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Jilin Province Weather Modification Offices Changchun 130062China Beijing Meteorological Bureau Beijing 100089China

According to the urbanization extent of Beijing area, and with 1980 as a turning point, the duration from 1961 to 2000 is divided into two periods: one is defined as the slow urbanization period from 1961 to 1980, and other one as the fast urbanization period from 1981 to 2000. Based on the 40-year’s precipi-tation data of 14 standard weather stations in Beijing area, the effect of urbanization on precipitation distribution is studied. It is found that there has been a noticeable and systematic change of winter precipitation distribution pattern between these two periods in Beijing area: in the slow urbanization period, the precipitation in the southern part of Beijing is more than that in the northern part; but in the fast urbanization period, the precipitation distribution pattern is reverse, i.e. the precipitation in the southern part is less than that in the northern part; But in other seasons, the precipitation distribution pattern did not change remarkably in general. The possible cause resulting in the change of winter precipitation distribution pattern, might be that with urban area extension, the effects of "urban heat island" and "urban dry island" become more and more intensified, and increase hydrometeors evapo-ration below precipitable cloud, and then cause less precipitation received on the ground surface in the downtown and the southern part. It is also noteworthy to further research why the precipitation distri-bution pattern does not change systematically in other seasons except winter after intense urbaniza-tion in Beijing area.

关键词： urbanization urban precipitation urban heat island urban dry island Beijing area

一种基于改进YOLOv7的相机标定特征点检测方法

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兵器装备工程学报 2024年第8期45卷 151-160页

作者：陈松闫国闯马方远王西泉田晓耕西安交通大学复杂服役环境重大装备结构强度与寿命全国重点实验室西安710049 中国兵器工业试验测试研究院西安710116

在基于视觉方法的军事目标检测等技术中,相机的精确标定是进行目标高精度测量的前提,同时也是开展后续图像处理、目标跟踪、三维重建的基础。相机标定的关键在于准确的检测图像中的标定特征点。以当前使用范围较广的棋盘格标定法为对象... 详细信息

在基于视觉方法的军事目标检测等技术中,相机的精确标定是进行目标高精度测量的前提,同时也是开展后续图像处理、目标跟踪、三维重建的基础。相机标定的关键在于准确的检测图像中的标定特征点。以当前使用范围较广的棋盘格标定法为对象,针对受干扰(模糊、重噪声、极端姿态和大镜头失真)的标定图像难以进行特征点提取的问题,提出一种融合改进YOLOv7-tiny深度学习网络和Harris角点检测的相机标定特征点检测算法。针对原始网络在相机标定特征区域检测中的各种问题,引入Gather-and-Distribute信息聚合分发机制替换YOLOv7-tiny的加强特征提取网络(FPN)部分,提高不同层之间特征融合的能力;在主干特征提取部分后加入Biformer注意力机制,提高对小尺寸特征点候选区域的捕捉能力;在Head部分使用改进Efficient Decoupled Head解耦头,在提高精度的同时维持了较低的计算开销。测试结果表明,改进后的YOLOv7-tiny网络对特征点候选区域检测的准确率有显著的提高,达到95.3%,证明了改进后网络的有效性和可行性。

关键词：相机标定深度学习 YOLOv7-tiny 信息聚合分发机制注意力机制 Harris算法

The impact of an urban dry island on the summer heat wave and sultry weather in Beijing City

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Chinese Science Bulletin 2010年第16期55卷 1657-1661页

作者： wang xiquan GONG YanBang Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

This paper studies interdecadal variations of heat waves and sultry weather (HW&SW) in Beijing City by using climatological data gathered from *** general, HW&SW decreased during the 1940s-1970s and increased during the *** variation trends in the number of HW&SW days coincide with air temperature variations, the greatest number of HW&SW days occurred during the 1940s rather than during the much hotter 1990s (which had an average 1.0°C higher air tem-perature than during the 1940s).The synoptic situations of HW&SW and the correlation analysis between HW&SW occurrences and the Western Pacific Subtropical High (WPSH) index seem to indicate that HW&SW days during the 1990s should exceed those during the 1940s;however, that is not the ***-1980s interdecadal variations of the Urban Dry Island (UDI) effect in Beijing City were analyzed in order to explain this inconsistent *** results show that, while the probability of HW&SW occurrences in Beijing City should have been greater due to global warming and increasing summer Urban Heat Island (UHI) intensity, the UDI effect is magnified by rapid *** addition, the physical comfort index is more sensitive to relative humidity under high temperature ***, the occurrence of HW&SW days during the 1990s is partially offset by the enhanced UDI in Beijing City.

关键词：天气闷热城市干岛北京夏季年代际变化

Seasonal variation of the temperature profile and its characteristics within urban roughness sublayer

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Chinese Science Bulletin 2009年第3期54卷 468-473页

作者： wang xiquan wang ZiFa GUO HU Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Beijing Meteorological Bureau Beijing 100089 China

By using conventional micro-meteorological observation data of Beijing Yuetan Park Tower (180 m), the temperature profile of urban boundary layer (UBL), its characteristics and seasonal variation are analyzed. The main results are as follows: (1) In winter, the interdiurnal surface air temperature varia- tion at the surface is not synchronized with that of the upper levels, other than in summer and other seasons, which illuminates the impacts of Beijing’s geographical location, sky view factor and stably stratified nocturnal inversion. (2) Except that the stratification is unstable around noon, the stratifica- tion in the roof layer or above-roof layer is of seasonal variability, which is weak unstable or weak sta- ble in winter or summer respectively. This weak stable stratification possibly inhibits urban pollutant dispersion upwards in summer season. (3) The effect of urban building rooftop on the UBL thermal state has seasonal difference, that is, the rooftop plays the role of heating or cooling the urban roughness sublayer, in summer or winter respectively, which is similar to the effects of the Qing- hai-Tibet Plateau on the atmospheric thermal state.

关键词：城市边界层温度季节变更北京

盐胁迫对食用型向日葵现蕾期叶片光合性能与冠层结构的影响

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中国生态农业学报（中英文） 2024年第1期32卷 141-152页

作者：董睿潇王永庆王鑫博李玉义王希全张宏媛宋佳珅于茹逄焕成王婧北方干旱半干旱耕地高效利用全国重点实验室/中国农业科学院农业资源与农业区划研究所北京100081

为探明不同程度盐胁迫对现蕾期食用型向日葵(下称“食葵”)光合作用的影响,测定分析轻度(全盐量1.00 g∙kg^(−1),LS)、中度(全盐量2.68 g∙kg^(−1),MS)和重度(全盐量4.93 g∙kg^(−1),HS)盐胁迫下,现蕾期食葵不同叶位叶片的光合性能和冠层... 详细信息

为探明不同程度盐胁迫对现蕾期食用型向日葵(下称“食葵”)光合作用的影响,测定分析轻度(全盐量1.00 g∙kg^(−1),LS)、中度(全盐量2.68 g∙kg^(−1),MS)和重度(全盐量4.93 g∙kg^(−1),HS)盐胁迫下,现蕾期食葵不同叶位叶片的光合性能和冠层结构参数。结果表明,盐胁迫降低了食葵叶片的净光合速率(Pn),其中MS和HS处理的Pn最大值较LS分别降低5.09%和38.69%,并减少了具有较高光合速率的叶片数量。盐胁迫降低了食葵顶叶的Pn,MS、HS处理的食葵顶叶Pn最大值较LS分别降低8.08%、14.66%。LS处理的光合速率受到气孔和非气孔双重因素的影响,而MS、HS处理主要受非气孔因素的影响。盐胁迫改变了食葵的株型,LS处理的冠层结构呈宝塔型,而MS和HS处理的冠层结构分别呈平展型和圆柱体型。盐胁迫会减小食葵总叶面积和主要功能叶面积,其中HS处理的总叶面积较LS、MS处理分别降低56.03%、47.74%,HS处理的最大单叶面积较LS、MS处理分别降低38.71%、49.46%;同时HS处理叶倾角最大值与LS、MS处理相比分别提高30.92%、14.59%。总之,盐胁迫会明显降低食葵主要功能叶片的光合性能和叶面积,并使其冠层结构由伸展型向收缩型变化,进而抑制植株正常生长。

关键词：食用型向日葵盐胁迫光合速率冠层结构

维普期刊数据库博看期刊

Foreshowing of the Western Pacific tropical cyclone track to PM10 air pollution episode in the Beijing area

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Chinese Science Bulletin 2009年第5期54卷 830-835页

作者： wang xiquan wang ZiFa YU Tong GONG YanBang Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Beijing Environmental Protection Monitoring Center Beijing 100084 China

By utilizing the air quality monitoring data and the NCEP reanalysis data, the relationship between thePM10 air pollution episode and synoptic situation is analyzed in the Beijing area. It is interesting to findthat PM10 air pollution episode in and around the Beijing area is correlated with the Western Pacifictropical cyclone track to some extent, namely when a tropical cyclone lands southward to the Chang-jiang River, PM10 air pollution episode is not easy to take place generally in the Beijing area; but when atropical cyclone moves northward and finally lands at the Korea Peninsula or the Japanese mainland,and under this condition the Beijing area is generally controlled by weak high or weak low for severaldays, PM10 air pollution episode often takes place in one day or several days. Above findings indicatethat predicting the Western Pacific tropical cyclone track can foretell whether or not PM10 air pollutionepisode takes place in the Beijing area, which can offer a technique for urban air quality prediction andair pollution source management in the Beijing area.

关键词： PM10 空气污染西太平洋热带飓风轨道北京空气质量

Evolutionary processes and sources of high-nitrate haze episodes over Beijing,Spring

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Journal of Environmental Sciences 2017年第4期29卷 142-151页

作者： Ting Yang Yele Sun Wei Zhang Zifa wang Xingang Liu Pingqing Fu xiquan wang State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Aviation Meteorological Center of China Beijing 100021 China State Key Laboratory of Water Environment Simulation School of Environment Beijing Normal University Beijing 100089 China

Rare and consecutive high-nitrate haze pollution episodes were observed in Beijing in spring2012. We present detailed characterization of the sources and evolutionary mechanisms of this haze pollution, and focus on an episode that occurred between 15 and 26 April. Submicron aerosol species were found to be substantially elevated during haze episodes, and nitrates showed the largest increase and occupation（average： 32.2%） in non-refractory submicron particles（NR-PM1）, which did not occur in other seasons as previously reported. The haze episode（HE） was divided into three sub-episodes, HEa, HEb, and HEc. During HEa and HEc, a shallow boundary layer, stagnant meteorological conditions, and high humidity favored the formation of high-nitrate concentrations, which were mainly produced by three different processes —daytime photochemical production, gas-particle partitioning, and nighttime heterogeneous reactions — and the decline in visibility was mainly induced by ***, unlike HEa and HEc, during HEb, the contribution of high nitrates was partly from the transport of haze from the southeast of Beijing — the transport pathway was observed at ~800–1000 m by aerosol Lidar —and the decline in visibility during HEb was primarily caused by PM（2.5）. Our results provide useful information for air quality improvement strategies in Beijing during Spring.

关键词： Haze Nitrate Sources Lidar Aerosol Chemical Speciation Monitor Boundary layer

Observation of Wind Shear during Evening Transition and an Estimation of Submicron Aerosol Concentrations in Beijing Using a Doppler Wind Lidar

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Journal of Meteorological Research 2017年第2期31卷 350-362页

作者： Yong CHEN Junling AN xiquan wang Yele SUN Zifa wang Jing DUAN State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029 Center for Excellence in Urban Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021 Chinese Academy of Meteorological Sciences Beijing 100081

The wind speed and direction measured over six months by a Doppler wind lidar（Windcube-8）were compared with wind cup anemometers mounted on the 325-m Beijing meteorological tower（BMT）.Five mountain–plain wind cases characterized by wind direction shear were selected based on the high-frequency（1.1 s）wind profile of the Windcube-8 and analyzed with 1-h mesoscale surface weather *** analyzed was the relationship between insitu PM_1（aerodynamic diameter≤1μm）concentrations measured at 260 m on BMT and the carrier-to-noise ratio（CNR）of the co-located *** results showed that the 10-min averaged wind speed and direction were highly correlated（R=0.96–0.99）at three matched levels（80,140,and 200 m）.The evening transition duration was1–3 h,with an average wind speed of 1 m s^（–1） at 80 m above the *** addition,there was a zero horizontalwind-speed zone along the wind direction shear line,and in one case,the wind speed was characterized by a Kelvin–Helmholtz gravity *** variability of the PM_1 concentrations was captured by the CNR of the Windcube-8 in a fair weather period without the long-range transport of dust.

关键词： mountain–plain wind wind shear wind lidar PM_1