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基于气象因子的EEMD-BP方法在电网用电量预测中的应用

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南方能源建设 2024年第1期11卷 122-132页

作者：张震肖莺任永建陈正洪湖北省气象服务中心湖北武汉430205 武汉区域气候中心湖北武汉430205 成都信息工程大学四川成都610225

[目的]随着风能、太阳能等清洁能源快速发展,电力系统的能源结构发生了重大变化,这使得电网安全运行的不确定性增大,也给精准用电量预测带来了新的挑战。电网用电量受众多因子的影响,而气象因子的影响显著,因此,分析气象因子对用电量精... 详细信息

[目的]随着风能、太阳能等清洁能源快速发展,电力系统的能源结构发生了重大变化,这使得电网安全运行的不确定性增大,也给精准用电量预测带来了新的挑战。电网用电量受众多因子的影响,而气象因子的影响显著,因此,分析气象因子对用电量精细化预测的影响显得尤为重要。[方法]利用2017年逐日用电量以及最高气温、平均气温、最低气温、气压、相对湿度、风速等气象数据,采用集合模态经验分解(EEMD)和BP神经网络组合预测方法,探讨气象因子对集合模态经验分解回归模型(EEMD-BP)方法预测用电量的影响。[结果]研究发现,平均气温、最高气温、最低气温、气压和相对湿度与用电量序列经EEMD分解后的低频分量存在较好的相关关系,而与高频分量和周期分量的相关性较弱。[结论]利用BP回归模型预测的用电量与实况误差较大,引进气象因子后,EEMD-BP得出的预测准确率有了明显的提高。研究表明,基于气象因子的EEMD-BP组合预测方法可有效提高用电量预测的准确率,可为完善短期用电量预测方法提供有效的技术支撑。

关键词：集合模态经验分解用电量气象因子精细化预测回归模型

基于气象因素的长江经济带湖北段夏季日最大电力负荷预测

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南方能源建设 2024年第1期11卷 133-142页

作者：王丽娟任永建王俊超欧阳威湖北省气象服务中心湖北武汉430205 中国气象局武汉暴雨研究所暴雨监测预警湖北省重点实验室湖北武汉430205

[目的]利用气候预测模式的气温数据对未来长江经济带湖北段武汉、黄石、宜昌夏季日最大电力负荷进行预测。[方法]基于武汉、黄石、宜昌2008~2019年逐日最大电力负荷数据、同期平均气温、最高气温、最低气温等气象要素资料以及RegCM4区... 详细信息

[目的]利用气候预测模式的气温数据对未来长江经济带湖北段武汉、黄石、宜昌夏季日最大电力负荷进行预测。[方法]基于武汉、黄石、宜昌2008~2019年逐日最大电力负荷数据、同期平均气温、最高气温、最低气温等气象要素资料以及RegCM4区域气候模式预测数据,对3个地区的气象敏感电力负荷特性进行分析。在此基础上,通过回归法和群粒子优化BP神经网络算法,对未来(2020~2096年)日最大电力负荷进行定量滚动预测。[结果]结果表明,夏季平均气温与气象敏感负荷关联度最大。预测武汉和宜昌两地的夏季日最大电力负荷相似,两种预测值较近10 a日最大电力负荷稳步增长,回归预测的增长率要略高于神经网络预测;宜昌增长率比武汉高,最高超过40%。黄石日最大电力负荷的预期值较其他两地呈现出明显不同预测结果。[结论]预测长江经济带的中大型城市夏季日最大电力负荷的变化规律,有助于规划未来所需额外的电网容量。

关键词：长江经济带湖北段气象因素模式预测最大电力负荷神经网络

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移栽期和种植密度对恩施雪茄烟叶品质的影响

中国农学通报 2024年第14期40卷 39-46页

作者：吴栩任永建李金建成丹余君成都信息工程大学大气科学学院成都610225 湖北省气象服务中心武汉430205 湖北省烟草科学研究院武汉430030

为探究移栽期和种植密度对雪茄烟烟叶产量和品质的影响,在恩施崔坝基地展开试验。设置3个移栽期处理(4月20日、4月30日、5月10日)和6个种植密度处理(100 cm×40 cm、100 cm×45 cm、100 cm×50 cm、110 cm×40 cm、110 cm×45 cm、110 c... 详细信息

为探究移栽期和种植密度对雪茄烟烟叶产量和品质的影响,在恩施崔坝基地展开试验。设置3个移栽期处理(4月20日、4月30日、5月10日)和6个种植密度处理(100 cm×40 cm、100 cm×45 cm、100 cm×50 cm、110 cm×40 cm、110 cm×45 cm、110 cm×50 cm),比较不同移栽期的烟株生育期、农艺性状、产量及等级结构、外观质量和感官评吸质量,选择最佳移栽期进行移栽,探究不同种植密度对烟株农艺性状、产量及等级结构的影响。结果表明:随着移栽期的推迟,烟株生育期明显缩短,集中在旺长期,与气温呈明显负相关;随着移栽期的推迟,烟叶的产量和品质均下降。此外,不同种植密度对烟株的生长具有一定影响。随着种植密度的增大,烟株的株高、最大叶长和叶宽整体上先增后减,适当增加行距和减小株距有利于提高产量。综合认为,恩施崔坝基地雪茄烟茄衣品种‘楚雪26号’的最佳移栽期在4月20日—4月30日,110 cm×50 cm的种植密度使烟株的农艺性状表现最好,110 cm×40 cm的种植密度能获得更高的经济效益。

关键词：雪茄烟移栽期种植密度产量品质

A Client Selection Method Based on Loss Function Optimization for Federated Learning

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Computer Modeling in Engineering & Sciences 2023年第10期137卷 1047-1064页

作者： Yan Zeng Siyuan Teng Tian Xiang Jilin Zhang Yuankai Mu yongjian ren Jian Wan School of Computer Science and Technology Hangzhou Dianzi UniversityHangzhou310018China Key Laboratory of Complex System Modeling and Simulation Ministry of EducationHangzhou310018China Zhejiang Engineering Research Center of Data Security Governance Hangzhou310018China Intelligent Robotics Research Center Zhejiang LabHangzhou311100China HDU-ITMO Joint Institute Hangzhou Dianzi UniversityHangzhou310018China

Federated learning is a distributedmachine learningmethod that can solve the increasingly serious problemof data islands and user data privacy,as it allows training data to be kept locally and not shared with other *** trains a globalmodel by aggregating locally-computedmodels of clients rather than their ***,the divergence of local models caused by data heterogeneity of different clients may lead to slow convergence of the global *** this problem,we focus on the client selection with federated learning,which can affect the convergence performance of the global model with the selected local *** propose FedChoice,a client selection method based on loss function optimization,to select appropriate local models to improve the convergence of the global *** firstly sets selected probability for clients with the value of loss function,and the client with high loss will be set higher selected probability,which can make them more likely to participate in ***,it introduces a local control vector and a global control vector to predict the local gradient direction and global gradient direction,respectively,and calculates the gradient correction vector to correct the gradient direction to reduce the cumulative deviationof the local gradient causedby *** experiments to verify the validity of FedChoice on CIFAR-10,CINIC-10,MNIST,EMNITS,and FEMNIST datasets,and the results show that the convergence of FedChoice is significantly improved,compared with FedAvg,FedProx,and FedNova.

关键词： Federated learning model aggregation Non-IID

物化探综合找矿方法在内蒙古喀喇沁旗大西沟萤石矿找矿中的应用

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西北地质 2024年第4期57卷 135-143页

作者：张成信任永健金松魏龙飞王艳超赵寒代小光河北省战略性关键矿产研究协同创新中心河北石家庄050031 中化地质矿山总局地质研究院北京100101

笔者以大西沟热液裂隙充填型萤石矿床为例,结合地质调查,联合应用1∶5万水系沉积物测量、1∶1万土壤地球化学剖面、1∶1万高精度磁测、1∶1万高密度电阻率剖面和1∶1万电阻率剖面综合技术方法开展了萤石找矿勘查的有效性试验研究。结果... 详细信息

笔者以大西沟热液裂隙充填型萤石矿床为例,结合地质调查,联合应用1∶5万水系沉积物测量、1∶1万土壤地球化学剖面、1∶1万高精度磁测、1∶1万高密度电阻率剖面和1∶1万电阻率剖面综合技术方法开展了萤石找矿勘查的有效性试验研究。结果表明:1∶5万水系沉积物测量工作可以缩小找矿目标区域;高精度磁测、高密度电阻率和视电阻率联合剖面物探技术方法相结合可有效地探测控矿断裂浅地表的空间延伸情况及规模;土壤地球化学剖面圈出的高F异常可有效地识别断裂构造的含矿性。将上述物探和化探综合技术方法应用到大西沟矿床外围,探测到控矿构造北西延伸至画匠沟村以北1000 m以上,并在地表发现两处矿化露头。对矿化露头经地表槽探工程揭露,浅地表矿体达工业规模,这为矿山外围深部勘查扩增工作提供了依据。同时该方法组合可为区域热液裂隙充填型萤石矿找矿工作提供一定的借鉴。

关键词：大西沟萤石矿物化探应用

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烟叶日光大棚漂浮育苗气象条件分析

中国农学通报 2024年第17期40卷 89-96页

作者：任恒沈雨夏金杜世晔任永建刘少霞曾繁蕊刘乔湖北省十堰市气象局湖北十堰442000 湖北省烟叶气象服务中心湖北十堰442000 湖北省气象服务中心武汉430000 恩施土家苗族自治州气象局湖北恩施445000

为掌握烟叶苗床期不同生育阶段对气象条件的需求,选取3个不同海拔高度的育苗日光大棚安装小气候站,结合棚外的烟叶生态气象站苗床期间的日照和总辐射量数据,对烟叶生育期叶龄生理指标进行观测,分析了不同海拔高度烟苗苗床期对温、湿、... 详细信息

为掌握烟叶苗床期不同生育阶段对气象条件的需求,选取3个不同海拔高度的育苗日光大棚安装小气候站,结合棚外的烟叶生态气象站苗床期间的日照和总辐射量数据,对烟叶生育期叶龄生理指标进行观测,分析了不同海拔高度烟苗苗床期对温、湿、光的要求。结果表明:影响日光大棚内烟苗生长的生态环境因子表现为气温因子>水分因子>光照因子。育苗期间从播种到出苗需要14~19 d,每长1片真叶需要4 d左右;整个育苗期平均温度为12.0~15.5℃,相对湿度控制在72.4%,营养液平均温度为11.0~15.1℃,育苗期所需活动积温为555.1~640.8℃;日照时数为247.0~293.0 h,总辐射为550.5~686.7 MJ/m^(2)。本文对不同海拔高度烟叶幼苗苗床期对温、湿、光的要求进行了研究总结,为开展烟叶种植全生育期气象服务提供了理论支撑。

关键词：烟叶漂浮育苗气象条件主成分分析

APPLICATION OF STOCHASTIC FINITE ELEMENT METHOD TO STrenGTH AND STABILITY ANALYSIS OF EARTH DAMS

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Acta Mechanica Solida Sinica 1994年第1期7卷 80-86页

作者： yongjian, ren Guoqing, Wang Derong, Wei Jizhong, Shi Zhejiang Univ China

This paper applies the stochastic finite element method to analyse the statistics of stresses in earth dams and assess the safety and reliability of the dams. Formulations of the stochastic finite element method are briefly reviewed and the procedure for assessing dam's strength and stability is described. As an example, a detailed analysis for an actual dam Nululin dam is performed. A practical method for studying built-dams based on the prototype observation data is described.

关键词： Accident prevention Failure (mechanical) Finite element method Random processes Reliability Stability Statistics Strength of materials Stress analysis Structural analysis Water levels

A Possible Abrupt Change in Summer Precipitation over Eastern China around 2009

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Journal of Meteorological Research 2017年第2期31卷 397-408页

作者： yongjian ren Lianchun SONG Zunya WANG Ying XIAO Bing ZHOU College of Atmospheric Science Nanjing University of Information Science & Technology National Climate Center China Meteorological Administration Hubei Key Laboratory for Heavy Rain Monitoring and Warning Research Institute of Heavy RainChina Meteorological Administration

Historical studies have shown that summer rainfall in eastern China undergoes decadal variations,with three apparent changes in the late 1970s,1992,and the late *** present observational study indicates that summer precipitation over eastern China likely underwent a change in the late 2000s,during which the main spatial pattern changed from negative–positive–negative to positive–negative in the meridional *** change in summer precipitation over eastern China may have been associated with circulation anomalies in the middle/upper troposphere.A strong trough over Lake Baikal created a southward flow of cold air during 2009–15,compared with 1999–2008,while the westward recession of the western Pacific subtropical high strengthened the moisture transport to the north,creating conditions that were conducive for more rainfall in the north during this *** phase shift of the Pacific Decadal Oscillation in the late 2000s led to the Pacific–Japan-type teleconnection wave train shifting from negative to positive phases,resulting in varied summer precipitation over eastern China.

关键词： eastern China summer precipitation interdecadal change Pacific–Japan-type teleconnection

Regulation of 2-acetyl-1-pyrroline and grain quality in early-season indica fragrant rice by nitrogen and silicon fertilization under different plantation methods

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Journal of Integrative Agriculture 2024年第2期23卷 511-535页

作者： yongjian Chen Lan Dai Siren Cheng Yong ren Huizi Deng Xinyi Wang Yuzhan Li Xiangru Tang Zaiman Wang Zhaowen Mo State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources College of AgricultureSouth China Agricultural UniversityGuangzhou 510642China Guangxi Key Laboratory of Agricultural Resources Chemistry and Biotechnology Yulin Normal UniversityYulin 537000China Key Laboratory for Conservation and Utilization of Subtropical Bio-Resources Education Department of Guangxi Zhuang Autonomous Region/College of Biology and PharmacyYulin Normal UniversityYulin 537000China Scientific Observing and Experimental Station of Crop Cultivation in South China Ministry of Agriculture and Rural AffairsGuangzhou 510642China Guangzhou Key Laboratory for Science and Technology of Fragrant Rice Guangzhou 510642China Key Laboratory of Key Technology for South Agricultural Machine and Equipment Ministry of Education/College of EngineeringSouth China Agricultural UniversityGuangzhou 510642China

Fragrant rice has a high market value,and it is a popular rice type among consumers owing to its pleasant *** methods,nitrogen(N)fertilizers,and silicon(Si)fertilizers can affect the grain yield and fragrance of fragrant ***,the core commercial rice production attributes,namely the head rice yield(HRY)and 2-acetyl-1-pyrroline(2-AP)content of fragrant rice,under various nitrogen and silicon(N-Si)fertilization levels and different plantation methods remain *** field experiment in this study was performed in the early seasons of 2018 and 2019 with two popular indica fragrant rice cultivars(Yuxiangyouzhan and Xiangyaxiangzhan).They were grown under six N-Si fertilization treatments(combinations of two levels of Si fertilizer,0 kg Si ha^(−1)(Si0)and 150 kg Si ha^(−1)(Si1),and three levels of N fertilizer,0 kg N ha^(−1)(N0),150 kg N ha^(−1)(N1),and 220 kg N ha^(−1)(N2))and three plantation methods(artificial transplanting(AT),mechanical transplanting(MT),and mechanical direct-seeding(MD)).The results showed that the N-Si fertilization treatments and all the plantation methods significantly affected the HRY and 2-AP content and related parameters of the two different fragrant rice *** with the Si0N0 treatment,the N-Si fertilization treatments resulted in higher HRY and 2-AP *** rates of brown rice,milled rice,head rice,and chalky rice of the fragrant rice also improved with the N-Si fertilization *** N-Si fertilization treatments increased the activities of N metabolism enzymes and the accumulation of N and Si in various parts of the fragrant rice,and affected their antioxidant response *** key parameters for the HRY and 2-AP content were assessed by redundancy ***,the structural equation model revealed that the Si and N accumulation levels indirectly affected the HRY by affecting the N metabolism enzyme activity,N use efficiency,and grain quality of fragrant ***,high N

关键词： fragrant rice 2-AP content head rice yield mechanical planting nitrogen silicon