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基于标准化降水指数的辽宁省大豆需水关键期干旱大气环流成因分析

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气象与环境学报 2024年第1期40卷 54-62页

作者：李菲张淑杰赵春雨胡春丽林蓉房一禾中国气象局沈阳大气环境研究所/辽宁省农业气象灾害重点实验室辽宁沈阳110166 辽宁省气候中心辽宁沈阳110166 东北冷涡研究重点开放实验室辽宁沈阳110166 盘锦国家气候观象台辽宁盘锦124000 辽宁省生态气象和卫星遥感中心辽宁沈阳110166

利用1971—2020年辽宁省54个气象站逐日降水量资料及逐日NCEP/NCAR(美国大气科学研究中心和美国国家环境预报中心)再分析资料,计算了辽宁省各站大豆需水关键期(开花期至结荚期)标准化降水指数,分析了大豆需水关键期典型干旱年份及其大... 详细信息

利用1971—2020年辽宁省54个气象站逐日降水量资料及逐日NCEP/NCAR(美国大气科学研究中心和美国国家环境预报中心)再分析资料,计算了辽宁省各站大豆需水关键期(开花期至结荚期)标准化降水指数,分析了大豆需水关键期典型干旱年份及其大气环流成因。结果表明:副热带西风急流位置异常引发的对流层高低空大气环流的不同配置是造成辽宁省大豆需水关键期不同气候特征干旱年的主要大气环流成因。当大豆需水关键期西风急流位置较常年偏北时易发生高温干旱,辽宁省大豆主产区一致受到较大影响,西风急流位置偏北,辽宁省位于高空急流轴南侧、高空辐散风场中心,西太平洋副热带高压位置阶段性异常偏北控制整个辽宁省,对流层风场贯穿高层至低层的下沉气流配合较差的水汽条件是发生高温干旱的主要大气环流成因;当大豆需水关键期西风急流位置偏南时易发生低温干旱,辽宁省大豆主产区中部和北部受影响较大,西风急流位置偏南,季节进程缓慢,西太平洋副热带高压位置较常年持续偏南、偏西,对流层上层垂直上升运动明显,冷空气活动频繁,但对流层中下层一致的下沉运动配合较差的水汽条件不利于降水产生,导致低温和干旱现象的同时发生。

关键词：大豆需水关键期干旱西风急流西太平洋副热带高压

Simulation and forecasting of fishery weather based on statistical machine learning

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Information Processing in Agriculture 2024年第1期11卷 127-142页

作者： Xueqian Fu chunyu Zhang Fuhao Chang Lingling Han Xiaolong zhao Zhengjie Wang Qiaoyu Ma National Innovation Center for Digital Fishery China Agricultural UniversityBeijingChina Key Laboratory of Smart Farming Technologies for Aquatic Animal and Livestock Ministry of Agriculture and Rural AffairsBeijingChina Beijing Engineering and Technology Research Center for Internet of Things in Agriculture BeijingChina College of Information and Electrical Engineering China Agricultural UniversityBeijingChina

As the new generation of artificial intelligence(AI)continues to evolve,weather big data and statistical machine learning(SML)technologies complement each other and are deeply integrated to significantly improve the processing and forecasting accuracy of fishery *** fishery weather services play a crucial role in fishery production,serving as a great safeguard for economic benefits and personal safety,enabling fishermen to carry out fishery production better,and contributing to the sustainable development of the fishery *** objective of this paper is to offer an understanding of the present state of research and development in SML technology for simulating and forecasting fishery ***,we analyze the current state of research and technical features of SML in weather and summarize the applications of SML in simulation and forecasting of fishery weather,which mainly include three aspects:fishery weather scenario generation,fishery weather forecasting,and fishery extreme weather *** also illustrate the main technical means and principles of SML ***,we summarize the most advanced SML fields and provide an outlook on their application value in the field of fishery weather.

关键词： Fishery weather Statistical machine learning Weather generation Weather forecasting Extreme weather warning

Crop pest image recognition based on the improved ViT method Author links open overlay panel

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Information Processing in Agriculture 2024年第2期11卷 249-259页

作者： Xueqian Fu Qiaoyu Ma Feifei Yang chunyu Zhang Xiaolong zhao Fuhao Chang Lingling Han College of Information and Electrical Engineering China Agricultural UniversityBeijingChina National Innovation Center for Digital Fishery China Agricultural UniversityBeijingChina Key Laboratory of Smart Farming Technologies for Aquatic Animal and Livestock Ministry of Agriculture and Rural AffairsBeijingChina Beijing Engineering and Technology Research Center for Internet of Things in Agriculture BeijingChina

The crop pests and diseases in agriculture is one of the most important reason for the reduction of bulk grain and oil crops and the decline of fruit and vegetable crop quality,which threaten macroeconomic stability and sustainable ***,the recognition method based on manual and instruments has been unable to meet the needs of scientific research and production due to its strong subjectivity and low *** recognition method based on pattern recognition and deep learning can automatically fit image features,and use features to classify and predict *** study introduced the improved Vision Transformer(ViT)method for crop pest image *** them,the region with the most obvious features can be effectively selected by block *** self-attention mechanism of the transformer can better excavate the special solution that is not an obvious lesion *** the experiment,data with 7 classes of examples are used for *** can be illustrated from results that this method has high accuracy and can give full play to the advantages of image processing and recognition technology,accurately judge the crop diseases and pests category,provide method reference for agricultural diseases and pests identification research,and further optimize the crop diseases and pests control work for agricultural workers in need.

关键词： Crop diseases recognition Fruit tree leaf disease Vision Transformer Deep learning Computer Vision

LNG螺旋骨架复合耐超低温柔性管道拉伸性能分析研究

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力学与实践 2024年第3期46卷 511-521页

作者：阎军步宇峰郭峰赵春雨杨志勋宁永庆尹原超大连理工大学工程力学系辽宁大连116024 大连理工大学宁波研究院浙江宁波315016 哈尔滨工程大学机电工程学院哈尔滨150001 大连理工大学海洋科学与技术学院辽宁盘锦124221

LNG螺旋骨架复合耐超低温柔性管道采用了以螺旋骨架支撑,多层复合材料缠绕的非粘接结构形式,这类结构的力学性能分析中涉及到几何大变形、超低温环境、复杂层间接触等难题。传统的柔性管道拉伸理论模型不再适用于这类结构形式。本文针... 详细信息

LNG螺旋骨架复合耐超低温柔性管道采用了以螺旋骨架支撑,多层复合材料缠绕的非粘接结构形式,这类结构的力学性能分析中涉及到几何大变形、超低温环境、复杂层间接触等难题。传统的柔性管道拉伸理论模型不再适用于这类结构形式。本文针对12英寸(1英寸=0.025 4 m)口径的低温柔性管道开展了常、低温拉伸性能实验研究,建立了低温柔性管道的精细数值模型,并通过实验进行了模型修正。基于所建立的数值模型开展了温度、支撑层参数对管道拉伸性能的敏感性分析。结果表明,低温环境下管道的抗拉伸性能提高了12.69%,支撑层螺距增大50%将导致管道的抗拉伸性能降低52.36%。本文的研究为LNG螺旋骨架复合耐超低温柔性管道的设计和优化提供了一定的参考和指导。

关键词： LNG螺旋骨架复合耐超低温柔性管道拉伸性能超低温数值模拟敏感性分析

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辽宁省精细化暴雨洪涝灾害风险评估与预评估

气象科技 2024年第3期52卷 403-414页

作者：敖雪翟晴飞赵春雨周晓宇崔妍李经纬李明倩辽宁省气候中心沈阳110166 辽宁省气象信息中心沈阳110166

基于辽宁省61个国家气象站1961—2020年和998个区域自动气象观测站建站至2020年逐小时、逐日降水资料,分析了辽宁省暴雨洪涝灾害主要致灾因子,计算了暴雨洪涝孕灾环境指标,完成了辽宁省暴雨洪涝灾害危险性评估。结果表明:暴雨洪涝高危... 详细信息

基于辽宁省61个国家气象站1961—2020年和998个区域自动气象观测站建站至2020年逐小时、逐日降水资料,分析了辽宁省暴雨洪涝灾害主要致灾因子,计算了暴雨洪涝孕灾环境指标,完成了辽宁省暴雨洪涝灾害危险性评估。结果表明:暴雨洪涝高危险性地区主要位于丹东;暴雨洪涝灾害人口高风险区主要位于沈阳和大连市区;经济高风险区主要位于大连和盘锦市区;水稻、玉米高风险区主要位于锦州、盘锦和丹东。利用辽宁省无缝隙智能网格预报数据对2022年7月28—29日的暴雨过程灾害风险进行了预评估,发现暴雨灾害危险性高值区域主要分布在朝阳、葫芦岛以及辽宁中部。暴雨灾害可能造成的人口、经济高风险区域主要位于辽宁西部和中部地区;暴雨灾害可能造成的水稻和玉米高风险区主要位于沈阳、铁岭和朝阳北部等地区。预计高风险区主要影响人口约为449万人,经济损失约为1432万元,受影响的水稻面积约为1.028万公顷、玉米面积约为1.798万公顷。通过灾后效果检验,发现预评估模型效果良好,可在实际的暴雨洪涝灾害风险评估业务中使用。

关键词：精细化暴雨洪涝风险预评估辽宁省

Life-Inspired Endogenous Dynamic Behavior of Lipid Droplet-like Microcompartments in Artificial Adipocyte-like Structures

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CCS Chemistry 2021年第11期3卷 2782-2794页

作者： Xiaoliang Wang Yan Huang Youping Lin Haixu Chen Junbo Li chunyu zhao Xiaoman Liu Li Yang Xin Huang MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage School of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbin 150001

Chemical systems that can replicate cellular behaviors are gaining increasing attention and are being used to study various biological ***,a protein-or amylose-based assembly at an oil/water interface was employed to construct a large compartmentalized adipocyte-like structure,and a lipid droplet-like microcompartment(amylose-polymerstabilized 2-ethyl-1-hexanol microcompartment),which exhibits floating behaviors driven by the amylose-polymer micelle solubilization,was introduced inside these adipocyte-like *** the lipase-based catalytic reaction and the external oil composition were controlled and another lipid droplet-like microcompartment(lipase-stabilized tributyrin microcompartment)was introduced,then a series of dynamic behaviors were exhibited by the two types of lipid droplet-like microcompartments,including growth,self-sorting,and fusion within the adipocyte-like ***,it is anticipated that this autonomous generation of hierarchical multicompartments represents a breakthrough compared to the traditional bottom-up strategies,and the artificial life systems we studied could contribute a chemical-based strategy of understanding the process of lipid droplet growth and fusion inside a living adipocyte cell.

关键词： artificial adipocyte-like structures lipid droplet-like microcompartments selfsorting endogenous growth dynamic behavior

翻译研究:从“文化转向”到“多文化转向”——埃德温·根茨勒访谈录(英文)

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外国文学研究 2016年第3期38卷 1-7页

作者：赵春雨上海交通大学外国语学院华东理工大学外国语学院

埃德温·根茨勒是美国著名翻译理论家、马萨诸塞大学阿默斯特分校比较文学系教授兼翻译中心主任,主要研究翻译理论、文学翻译以及后殖民理论,著有《美洲的翻译与身份认同:翻译理论的新方向》(2007)、《当代翻译理论》(1993)等,曾与玛丽... 详细信息

埃德温·根茨勒是美国著名翻译理论家、马萨诸塞大学阿默斯特分校比较文学系教授兼翻译中心主任,主要研究翻译理论、文学翻译以及后殖民理论,著有《美洲的翻译与身份认同:翻译理论的新方向》(2007)、《当代翻译理论》(1993)等,曾与玛丽亚·铁木志科主编《翻译和权力》(2002),与苏珊·巴斯内特主编《翻译论丛》系列丛书。在本次访谈中,根茨勒教授以翻译研究的"文化转向"开始,对其中有关"操纵"、"意识形态"、"译者主体性"等关键问题做了深度分析,并进一步探讨翻译研究与文化研究的关系,以及文化视角翻译研究的发展趋势。根茨勒教授认为,文化视角的翻译研究有"宏观地域倾向"和"微观地域倾向",将会出现更广泛意义的"多文化转向"。

关键词：埃德温·根茨勒翻译研究文化转向多文化转向

Effects of Light and Temperature Factors on Biomass Accumulation of Winter Wheat

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Meteorological and Environmental Research 2013年第8期4卷 41-46页

作者： Pengli Ma Yihao Ma Jinyong Pu chunyu zhao Weitai Wang Key Laboratory of Arid Climatic Change and Disaster Reduction of Gansu Province Institute of Arid MeteorologyChina Meteorological Administration / Key Open Laboratory of Arid Change and Disaster Reduction of CMA Lanzhou Regional Climate Center Binjiang Institute of Nanjing University of Information Tianshui Agrometeorological Experiment Station of Gansu Province Climate Center of Liaoning Meteorological Bureau Xifeng Agrometeorological Experiment Station of Gansu Province

[Objective] The study aimed to discuss the influence of light and temperature factors on biomass accumulation of winter wheat at each growth stage and changes in biomass of each organ. [Method] Based on the observation data from Xifeng Agrometeorological Experiment Station of Gansu Province, including phenophase and yield factors of winter wheat in 1981 -2008, biomass at three-leaves, overwintering, jointing, heading, milky maturity, and maturity stages in 1995 -2008, and meteorological data in 1995 -2008, the variation patterns of the biomass accumulation and the influence of TEP （thermal effectiveness photosynthetically active radiation） on the biomass of winter wheat at every growth stage were ana- lyzed. [Result] The biomass accumulation of winter wheat in the whole growth period presented ＂S＂ curve, with the maximum value from heading to milky maturity stage. Since 1981, TEP from heading to milky maturity stage increased with a rate of 3. 314 MJ/（m2 · a）, and the changing curves of TEP at other stages were like parable curves. TEP from turning green to jointing stage and from milky maturity to maturity stage had a higher value in the 1990s and a lower *** in the 1980s and early 21st century, while that from jointing to heading stage had a lower value in the 1990s but a higher value in the 1980s and early 21st century. There was a significant correlation between TEP at each growth stage and the actual yield. LAI （leaf area index） at each development stage also had a significant correlation with the utilization rate of TEP at corresponding stage. When LAI at jointing and heading stages increased by I, the utilization rate of TEP correspondingly increased by 0. 049 and 0.259 g/MJ respectively. [ Conclusion] The research could provide theoretical references for the scientific planting and management of winter wheat in future. Key words Light and temperature factors; Winter wheat; Biomass; Influence; China

关键词： Light and temperature factors Winter wheat Biomass Influence China

High-repetition-rate and high-power efficient picosecond thin-disk regenerative amplifier

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High Power Laser Science and Engineering 2024年第2期12卷 16-23页

作者： Sizhi Xu Yubo Gao Xing Liu Yewang Chen Deqin Ouyang Junqing zhao Minqiu Liu Xu Wu chunyu Guo Cangtao Zhou Qitao Lue Shuangchen Ruan Key Laboratory of Advanced Optical Precision Manufacturing Technology of Guangdong Higher Education Institutes Sino-German College of Intelligent ManufacturingShenzhen Technology UniversityShenzhenChina Han’s Laser Technology Industry Group Co. Ltd.ShenzhenChina Shenzhen Key Laboratory of Laser Engineering College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhenChina Shenzhen Key Laboratory of Ultraintense Laser and Advanced Material Technology College of Engineering PhysicsShenzhen Technology UniversityShenzhenChina

We present an effective approach to realize a highly efficient,high-power and chirped pulse amplification-free ultrafast ytterbium-doped yttrium aluminum garnet thin-disk regenerative amplifier pumped by a zero-phonon line 969 nm laser *** amplifier delivers an output power exceeding 154 W at a pulse repetition rate of 1 MHz with custom-designed 48 pump *** exceptional thermal management on the thin disk through high-quality bonding,efficient heat dissipation and a fully locked spectrum collectively contributes to achieving a remarkable optical-to-optical efficiency of 61%and a near-diffraction-limit beam quality with an M2 factor of *** the best of our knowledge,this represents the highest conversion efficiency reported in ultrafast thin-disk regenerative ***,the amplifier operates at room temperature and exhibits exceptional stability,with root mean square stability of less than 0.33%.This study significantly represents advances in the field of laser amplification systems,particularly in terms of efficiency and average *** advantageous combination of high efficiency and diffraction limitation positions the thin-disk regenerative amplifier as a promising solution for a wide range of scientific and industrial applications.

关键词： high efficiency high power picosecond laser regenerative amplifier thin-disk laser