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电力系统中压电网谐振关键元器件评估

中国电力 2024年第2期57卷 127-137页

作者：周子康陶顺薛超凡袁威徐永海新能源电力系统国家重点实验室(华北电力大学) 北京102206

模态分析法可以获得最丰富的谐振信息,现有灵敏度分析方法可以得到每种元器件对谐振影响程度的排序,但无法明确辨别谐振关键元件和谐振电路。首先,通过推导对各参与因子的物理意义进行了解释,归纳了现有的2种灵敏度分析方法;然后,考虑... 详细信息

模态分析法可以获得最丰富的谐振信息,现有灵敏度分析方法可以得到每种元器件对谐振影响程度的排序,但无法明确辨别谐振关键元件和谐振电路。首先,通过推导对各参与因子的物理意义进行了解释,归纳了现有的2种灵敏度分析方法;然后,考虑不同属性元器件取值范围的差异性及逆变器外特性的影响,提出了一种适用于配电网谐振关键元件和电路的识别方法;最后,通过算例分析和PSCAD仿真结果,验证了所得谐振关键元器件的准确性。该方法可以较为准确地识别出系统固有谐振的关键元器件,为研究谐波谐振问题及其抑制、事故调查分析等提供参考。

关键词：模态分析法灵敏度分析谐波谐振谐振关键元件谐振关键电路

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以计算思维为导向的高中地理教学探究与实践

吉林省教育学院学报 2024年第1期40卷 53-58页

作者：曹玉峰周子康韩文东褚言皓深圳市第二十二高级中学(深圳理工大学附属中学)

计算思维将具体问题分解化、抽象化。高中地理教学模式日益强调学生思维的严谨性与逻辑性。将计算思维融入高中地理教学之中,提高教学效率是优化高中地理教学方式重要的探索路径之一。本文将以计算思维为导向,提出高中地理学科教学中计... 详细信息

计算思维将具体问题分解化、抽象化。高中地理教学模式日益强调学生思维的严谨性与逻辑性。将计算思维融入高中地理教学之中,提高教学效率是优化高中地理教学方式重要的探索路径之一。本文将以计算思维为导向,提出高中地理学科教学中计算思维的培养策略,并结合人教版高中地理选择性必修一教材中“地球的运动”相关内容与知识点,以区时的计算作为切入点,阐述高中地理教学过程中如何渗透计算思维,教会学生解决地理学科问题,以期探讨高中地理教学模式的优化与改进。

关键词：计算思维高中地理教学模式

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基于多元国土空间整治情景模拟的生态系统服务功能分区

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农业工程学报 2021年第22期37卷 262-270页

作者：周子康刘殿锋武汉大学资源与环境科学学院武汉430079

生态系统服务功能分区是科学管理生态系统的重要手段。国土空间整治能够通过综合治理闲置、低效和生态退化国土资源,改变国土空间结构与布局,从而对生态系统功能产生影响。现有研究较少关注土地整治措施对未来生态系统服务空间集聚模式... 详细信息

生态系统服务功能分区是科学管理生态系统的重要手段。国土空间整治能够通过综合治理闲置、低效和生态退化国土资源,改变国土空间结构与布局,从而对生态系统功能产生影响。现有研究较少关注土地整治措施对未来生态系统服务空间集聚模式的潜在影响作用,整治措施的生态导向性有待提升。因此,该研究以山东招远市为例,设计了基准情景、废弃矿区修复情景以及城乡建设用地整治情景,定量化预测生态系统服务变化特征,并运用模糊C均值聚类算法开展生态系统功能区划定。结果表明,整治情景下土地利用数量结构变化显著,各生态系统服务能力均有所提升。全域可以划分为生态综合区、生境保育区、固碳释氧区、固碳产粮区、生态维护区5个生态功能区。与基准情景相比,废弃矿区修复情景下各生态功能区60%生态系统服务水平持平,28%处于劣势,仅12%显著提升。城乡建设用地整治则能够显著提升全域自然娱乐能力,总体增长了1.89%。生境保育区的自然娱乐和粮食生产能力平均值分别增加了0.01和0.10,固碳释氧区的生境质量、水源涵养能力分别增长了20.69%和100%。研究表明全面提升生态系统多功能性需要综合开展多元的国土空间整治措施。

关键词：土地利用整治生态系统服务生态功能分区 FCM聚类

Constrained docking control for shipborne UAV SideArm recovery

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Chinese Journal of Aeronautics 2024年第5期37卷 39-59页

作者： zikang SU Zhuolin XING Xuebing LI Chuntao LI Xinwei WANG Honglun WANG College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China School of Engineering and Materials Science Queen Mary University of LondonLondon E14NSUK School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China

In this work,we sought to investigate constrained docking control during shipborne SideArm recovery of an Unmanned Aerial Vehicle(UAV)under preassigned safe docking constraints,rough ocean environments,and different initial *** aim was to solve the UAV tracking-lag problem that manifests when attempting to dock with a rapidly moving SideArm and to improve the accuracy and rapidity of ***,together with the formulations of the shipborne SideArm system and environmental airflows,the affine nonlinear dynamics of the hook was established to reduce tracking ***,echo state network approximators with good approximation capacity and low computational consumption were designed to accurately approximate the UAV’s unknown nonlinear *** feedforward compensation provided by these approximators,a nonlinear-mapping-based constrained docking control law was developed for shipborne SideArm recovery of *** approach to controlling the docking trajectory and the forward docking speed of the UAV can achieve rapid and exact docking with a moving SideArm,without violating the preassigned safe docking-constraint *** under different docking scenarios were used to validate the effectiveness and advantages of the proposed docking-control algorithm.

关键词： SideArm recovery Unmanned aerial vehicle Docking control Nonlinear mapping Echo state network

Study on the dynamic mechanical properties of winding-block axial structure considering short circuit strain rate effect

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High Voltage 2024年第2期9卷 380-390页

作者： Xinyu Wang Ping Wang Jianghai Geng zikang Zhang Fangcheng Lü Shuguo Gao Hebei Provincial Key Laboratory of Power Transmission Equipment Security Defense North China Electric Power UniversityBaodingChina State Grid Hebei Electric Power Research Institute ShijiazhuangChina

Transformers may suffer multiple short-circuit impacts during long-term operation,and axial instability is one of the typical types of serious accidents caused by short-circuit *** axial instability form of the winding-block structure is analysed,and the dynamic solution of the winding short-circuit electromagnetic force is obtained by estab-lishing the three-dimensional magnetic-circuit-force multi-physical field coupling simulation *** influence of strain rate on the cushion block constitutive equation is corrected,and the modified model is verified by short-circuit impact test and quasi-static *** research results show that for 110 kV 31.5 MVA transformers,the maximum electromagnetic axial resultant force of winding is 363.16 kN,and the ultimate tilt force is 1214.2 *** pre-tightening force configuration is accordingly recom-mended to range from 363.16 to 608.28 kN,which is narrowed by 18.49%compared with the static calculation method;Meanwhile,adding a logarithmic strain rate correction term to the classical constitutive equation of the cushion block can achieve a good correction of the stress-strain relationship with the coefficient of determination above 0.99,and the cushion block has a larger elastic modulus under high strain rate *** research results provide an important theoretical reference for the axial stability structure of transformers.

关键词： axial correction structure

组合投资双目标概率准则模型及GASS II算法求解

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计算机工程 2006年第19期32卷 185-187页

作者：周子康杨衡唐万生中国科学院数学与系统科学研究院北京100080 天津大学系统工程研究所天津300072

考虑到中国证券交易的限制规定及现实投资者并非完全理性的决策行为,给出了组合投资收益-损失风险双目标概率准则的整数规划模型。通过证券收益经验分布,应用分层抽样的随机模拟,并结合动态变化算子的遗传算法,构造GASS II遗传模拟混合... 详细信息

考虑到中国证券交易的限制规定及现实投资者并非完全理性的决策行为,给出了组合投资收益-损失风险双目标概率准则的整数规划模型。通过证券收益经验分布,应用分层抽样的随机模拟,并结合动态变化算子的遗传算法,构造GASS II遗传模拟混合算法,进行概率准则模型的优化求解。股票相关性由其秩相关系数给出,算法将秩和区间划分相联系,指导分层抽样。GASS II算法能有效刻画收益分布的“高峰厚尾”,激发遗传算法的隐含并行搜索特性,避免早熟现象,提高寻优效率与精度。最后给出了一个投资组合实证分析算例的收益-损失风险有效前沿。

关键词：组合投资概率准则模型动态遗传算子随机模拟分层抽样

基于分层抽样的模拟禁忌混合智能优化算法TSII

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计算机工程 2006年第9期32卷 175-177页

作者：周子康杨衡唐万生中国科学院数学与系统科学研究院北京100080 天津大学系统工程研究所天津300072

将分层抽样随机模拟与禁忌搜索结合,构造了TS II模拟禁忌混合智能优化算法。随机模拟采用缩减方差、加速收敛的分层抽样技术,保证抽样遍布于整个搜索空间,避免禁忌搜索路径往返重复,克服禁忌搜索对初始解的依赖,算法同时使用禁忌表与希... 详细信息

将分层抽样随机模拟与禁忌搜索结合,构造了TS II模拟禁忌混合智能优化算法。随机模拟采用缩减方差、加速收敛的分层抽样技术,保证抽样遍布于整个搜索空间,避免禁忌搜索路径往返重复,克服禁忌搜索对初始解的依赖,算法同时使用禁忌表与希望表,将分散搜索与集中搜索相结合,增强算法的并行处理能力,提高寻优的效率与精度。Benchmark问题评测结果显示出了该算法的有效性。

关键词：禁忌搜索算法随机模拟分层抽样混合优化算法

Regulation of the multi-emission centers in carbon dots via a bottom-up synthesis approach

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Chinese Chemical Letters 2024年第9期35卷 238-242页

作者： Bohan Zhang Bingzhe Wang Guichuan Xing zikang Tang Songnan Qu Joint Key Laboratory of the Ministry of Education Institute of Applied Physics and Materials EngineeringUniversity of MacaoMacao 999078China

Understanding the luminescence mechanisms and regulating the emission centers of carbon dots(CDs)are important for advancing their related *** this work,we systematically investigate the formation processes of multi-emission centers in CDs synthesized through a bottom-up approach by controlling the solvothermal reaction *** synthesized at a lower temperature(140℃,140-CDs)exhibit smaller particle sizes(3–4 nm)with dominant green–yellow emission,while CDs synthesized at a higher temperature(180℃,180-CDs)exhibit larger particle sizes(8–9 nm)with enhanced red emission and emerging near-infrared(NIR)*** green–yellow emission and red emission originate from the core state and the surface-related state,respectively,and the emissions could be regulated by temperature-controlled dehydration and carbonization *** clear NIR emission center in 180-CDs is attributable to the increased content of radical defects in the cores during the increased dehydration and carbonization processes during higher-temperature solvothermal treatment.

关键词： Carbon dot Photoluminescence Defect state Core state Temperature regulation

Three-dimensional thermohaline structure estimation derived from HY-2 satellite data over the Maritime Silk Road and its applications

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Acta Oceanologica Sinica 2024年第5期43卷 41-53页

作者： Zhiqiang Chen Xidong Wang Xiangyu Wu Yuan Cao zikang He Dakui Wang Jian Chen Key Laboratory of Marine Hazards Forecasting Ministry of Natural ResourcesHohai UniversityNanjing 210024China Laboratory for Regional Oceanography and Numercial Modeling Qingdao Marine Science and Technology CenterQingdao 266061China National Marine Environmental Forecasting Center Ministry of Natural ResourcesBeijing 100081China Beijing Institute of Applied Meteorology Beijing 100029China

Estimated ocean subsurface fields derived from satellite observations provide potential data sources for operational marine environmental monitoring and prediction *** study employs a statistic regression reconstruction method,in combination with domestic autonomous sea surface height and sea surface temperature observations from the Haiyang-2(HY-2)satellite fusion data,to establish an operational quasi-realtime three-dimensional(3D)temperature and salinity products over the Maritime Silk *** products feature a daily temporal resolution and a spatial resolution of 0.25°×0.25°and exhibit stability and *** have demonstrated the accuracy of the reconstructed thermohaline fields in capturing the 3D thermohaline variations through comprehensive statistical evaluations,after comparing them against Argo observations and ocean analysis data from *** results illustrate that the reconstructed fields effectively represent seasonal variations in oceanic subsurface structures,along with structural changes resulting from mesoscale processes,and the upper ocean’s responses to tropical ***,the incorporation of HY-2 satellite observations notably enhances the accuracy of temperature and salinity reconstructions in the Northwest Pacific Ocean and marginally improves salinity reconstruction accuracy in the North Indian Ocean when compared to the World Ocean Atlas 2018 monthly climatology thermohaline *** a result,the reconstructed product holds promise for providing quasi-real-time 3D temperature and salinity field information to facilitate fast decisionmaking during emergencies,and also offers foundational thermohaline fields for operational ocean reanalysis and forecasting *** contributions enhance the safety and stability of ocean subsurface activities and navigation.

关键词： HY-2 satellite observations subsurface structures reconstruction Maritime Silk Road operational thermohaline product