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基于多变量模糊控制的直流微网混合储能策略

高电压技术 2018年第1期44卷 126-135页

作者：李凤婷曾祥军夏令琴新疆大学可再生能源发电与并网技术教育部工程研究中心乌鲁木齐830047 云南电网有限责任公司昆明供电局昆明650000 国网新疆电力公司乌鲁木齐供电公司乌鲁木齐830011

为解决传统模糊控制器未考虑各电气量之间相互影响而导致控制准确性和协调性不足的问题，综合考虑直流微网中的微源出力、负荷需求及储能状态3者关系，提出基于母线电压波动、飞轮及蓄电池储能状态的混合储能调度方案；基于该调度方案... 详细信息

为解决传统模糊控制器未考虑各电气量之间相互影响而导致控制准确性和协调性不足的问题，综合考虑直流微网中的微源出力、负荷需求及储能状态3者关系，提出基于母线电压波动、飞轮及蓄电池储能状态的混合储能调度方案；基于该调度方案设计了考虑电气量间相互影响的多变量模糊控制器：采用带权值相乘方法建立计及电气量间相互影响的模糊关系矩阵，在此基础上对模糊输入量进行修正，建立模糊规则库，并对解模糊结果进行逻辑判断，生成储能系统的充放电控制信号；提出了以直流母线电压波动最小为目标，以瞬时功率平衡、储能装置充放电限制为约束条件的混合储能充放电优化方法。仿真结果表明当直流微网内母线电压波动超过5％时，储能系统可根据飞轮和蓄电池的储能状态，选择合适运行方式快速投入，从而维持直流母线电压的稳定；同时也验证了多变量模糊控制器与混合储能充放电优化方法的可行性和有效性，该研究对于工程实践和理论研究具有一定的参考价值。

关键词：直流微网电压波动混合储能模糊控制逻辑判断线性优化

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微网线路保护综述

电测与仪表 2017年第8期54卷 52-57页

作者：夏令琴李凤婷新疆大学电气工程学院乌鲁木齐830047

含逆变器微源的微网线路故障时,由于逆变器的限流作用,流过逆变器的故障电流被限制在两倍额定电流以内,造成含逆变器微源的微网并、离网模式下故障电流差距较大,使得基于固定值的常规过流保护不适用于微网。基于上述问题,对造成微网线... 详细信息

含逆变器微源的微网线路故障时,由于逆变器的限流作用,流过逆变器的故障电流被限制在两倍额定电流以内,造成含逆变器微源的微网并、离网模式下故障电流差距较大,使得基于固定值的常规过流保护不适用于微网。基于上述问题,对造成微网线路故障电流不确定性的影响因素作出总结,主要有微网运行方式,DG接入退出、布局容量、控制方式,并对它们的影响作了分析。文中着重综合概括了目前国内外微网线路保护研究热点,并按是否依赖通信及保护原理的实现方法做了划分。最后针对目前微网线路保护存在的问题探讨其可能的发展方向。

关键词：微网线路保护逆变器分布式电源

A356铝合金扫描式微弧氧化涂层的成膜过程及耐腐蚀性能

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材料研究学报 2016年第12期30卷 914-920页

作者：夏伶勤韩建民杨莎杨智勇李卫京北京交通大学机械与电子控制工程学院北京100044

采用扫描式微弧氧化(SMAO)技术在A356铝合金表面制备了陶瓷涂层。测定了反应过程中涂层的电压-时间、动力学生长曲线,研究了涂层的显微组织、成分分布,分析涂层的相组成及显微硬度分布,并比较了氧化前后极化曲线的变化。结果表明,在硅... 详细信息

采用扫描式微弧氧化(SMAO)技术在A356铝合金表面制备了陶瓷涂层。测定了反应过程中涂层的电压-时间、动力学生长曲线,研究了涂层的显微组织、成分分布,分析涂层的相组成及显微硬度分布,并比较了氧化前后极化曲线的变化。结果表明,在硅酸盐溶液中获得的涂层主要由α-Al_2O_3、γ-Al_2O_3和莫来石组成,涂层与基体呈现良好的冶金结合。与A356传统式微弧氧化(CMAO)涂层相比,SMAO涂层中α-Al_2O_3含量略多、孔隙率更低,显微硬度更高。此外,两种氧化处理之后,铝合金的耐腐蚀能力均得到显著提高。

关键词：材料失效与防护铝合金扫描式微弧氧化陶瓷膜腐蚀性能

添加K_2ZrF_6对钛合金微弧氧化膜层组织结构的影响

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北京交通大学学报 2013年第2期37卷 114-118页

作者：夏伶勤韩建民李卫京杨智勇北京交通大学机械与电子控制工程学院北京100044

采用交流电源对TA15合金进行微弧氧化处理,研究了在NaAlO2-Na3PO4溶液体系中添加K2ZrF6对膜层组织结构的影响.利用XRD、SEM和EDS等手段分析了膜层的相组成及表面形貌,探讨了添加剂K2ZrF6对成膜速率、膜层结构的影响,借助热震实验研究了... 详细信息

采用交流电源对TA15合金进行微弧氧化处理,研究了在NaAlO2-Na3PO4溶液体系中添加K2ZrF6对膜层组织结构的影响.利用XRD、SEM和EDS等手段分析了膜层的相组成及表面形貌,探讨了添加剂K2ZrF6对成膜速率、膜层结构的影响,借助热震实验研究了陶瓷膜与基体的结合力,并利用热阻隔性能测试评价了不同溶液中所形成膜层的热阻隔效果.加入K2ZrF6后,微弧氧化的成膜速率增加.SEM结果表明:K2ZrF6使膜层表面粗糙度降低,膜层内部缺陷减少.EDS线扫描分析表明:添加K2ZrF6后氧化膜层中出现大量锆元素,且其含量随距膜/基界面距离的增加而增加.XRD结果显示,未添加K2ZrF6溶液制得的膜层主要由Al2TiO5和Rutile-TiO2相组成;而添加K2ZrF6后,膜层中生成了隔热性良好的ZrO2相.热物性相关测试显示:经K2ZrF6调制后的膜层抗热震性能降低,但具有更加优良的热阻隔性能.

关键词：钛合金微弧氧化陶瓷涂层氧化锆

Potential dependence in electrocatalysis: a theoretical perspective

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Science China Chemistry 2025年第1期68卷 21-25页

作者： Leyu Liu Zhaoming xia Zeyu Wang Yinjuan Chen Hai xiao Department of Chemistry Tsinghua University Fundamental Science Center of Rare Earths Ganjiang Innovation Academy Chinese Academy of Sciences Key Laboratory of Advanced Catalytic Materials and Technology Advanced Catalysis and Green Manufacturing Collaborative Innovation Center Changzhou University

Electrocatalysis is a key technology for the new energy era and sustainable development, serving as the interface for interconversion of electrical and chemical energies, which spans a wide spectrum of applications in sustainable energy and environmental engineering. Electrocatalytic reactions including electrochemical CO2reduction reaction （eCO2RR）, hydrogen evolution reaction （HER）, and oxygen evolution/reduction reactions （OER/ORR）, hold essential promise for renewable energy technologies as well as complement the biogeochemical carbon and oxygen cycles.

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Inexact proximal gradient algorithm with random reshuffling for nonsmooth optimization

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Science China(Information Sciences) 2025年第1期68卷 219-237页

作者： xia JIANG Yanyan FANG xianlin ZENG Jian SUN Jie CHEN National Key Lab of Autonomous Intelligent Unmanned Systems School of AutomationBeijing Institute of Technology Beijing Institute of Technology Chongqing Innovation Center School of Electronic and Information Engineering Tongji University

Proximal gradient algorithms are popularly implemented to achieve convex optimization with nonsmooth regularization. Obtaining the exact solution of the proximal operator for nonsmooth regularization is challenging because errors exist in the computation of the gradient; consequently, the design and application of inexact proximal gradient algorithms have attracted considerable attention from researchers. This paper proposes computationally efficient basic and inexact proximal gradient descent algorithms with random reshuffling. The proposed stochastic algorithms take randomly reshuffled data to perform successive gradient descents and implement only one proximal operator after all data pass through. We prove the convergence results of the proposed proximal gradient algorithms under the sampling-without-replacement reshuffling *** computational errors exist in gradients and proximal operations, the proposed inexact proximal gradient algorithms can converge to an optimal solution neighborhood. Finally, we apply the proposed algorithms to compressed sensing and compare their efficiency with some popular algorithms.

关键词： proximal operator random reshuffling inexact computation compressed sensing nonsmooth optimization

Intermolecular reductive coupling of aliphatic ketones with alkynes and alkenes by BCN photocatalysts

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Science China Chemistry 2025年第1期68卷 181-185页

作者： Yanping xia Luyang Sun Jiajia Cheng Sibo Wang Meifang Zheng Xinchen Wang State Key Laboratory of Photocatalysis on Energy and Environment College of Chemistry Fuzhou University

A photocatalytic process was developed for intermolecular reductive coupling of aliphatic ketones with alkynes/alkenes to furnish tertiary alcohols. Mechanistic studies support that boron carbonitrides(BCN) promote the single electron reduction of unactivated aliphatic ketones to generate ketyl radicals with visible light irradiation, which then react with alkynes and alkenes to afford the allylic and aliphatic alcohols, respectively. The heterogeneous photocatalytic system is compatible with diverse substrates including pharmaceutical-related molecules(43 examples) with reusability and scale-up experiments, verifying the complementary synthetic utility of this method to the homogeneous catalysts.

关键词： aliphatic ketones ketyl radical intermolecular cross-coupling tertiary alcohols

成型压力对Ti(C,N)基金属陶瓷微观组织结构和力学性能的影响

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材料与冶金学报 2023年第3期22卷 249-255页

作者：方一航夏伶勤陈光吴韬于湘陈凯敏浙江机电职业技术学院增材制造学院杭州310053 台州学院浙江省工量刃具检测与深加工技术研究重点实验室浙江台州318000

以Ti(C,N)为基体硬质相,Ni和Co为金属黏结相,WC、Mo_(2)C和TaC为第二相碳化物,借助真空热压烧结技术制备了Ti(C,N)基金属陶瓷,探究了成型压力对金属陶瓷物相组成、微观形貌和成分、相对致密度、显微硬度、断裂韧性和抗弯强度的影响.研... 详细信息

以Ti(C,N)为基体硬质相,Ni和Co为金属黏结相,WC、Mo_(2)C和TaC为第二相碳化物,借助真空热压烧结技术制备了Ti(C,N)基金属陶瓷,探究了成型压力对金属陶瓷物相组成、微观形貌和成分、相对致密度、显微硬度、断裂韧性和抗弯强度的影响.研究结果表明:成型压力并未改变金属陶瓷的物相组成,所有试样均展现出典型的芯-环结构;无压成型烧结制备出的金属陶瓷不仅具有典型的黑芯-灰白双环结构,还呈现另一种白芯灰环结构.同时,金属陶瓷的晶粒度得到了细化.力学性能测试结果表明:成型压力达到8 MPa,金属陶瓷的相对致密度、显微硬度、断裂韧性和抗弯强度达到最大值,分别为99.1%,19.39 GPa, 7.84 MPa·m^(1/2)和1 488 MPa.金属陶瓷的断裂模式主要为沿晶断裂,并呈现较多的韧窝和撕裂棱.

关键词： Ti(C,N)基金属陶瓷成型压力微观组织结构芯-环结构力学性能

Prospects on mangrove knowledge services in the smart era: From plant atlas to knowledge graphs

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Science China Earth Sciences 2025年第1期68卷 111-127页

作者： Zhi-Wei HOU Wenlong JING Cheng-Zhi QIN Ji YANG Qing xia xiaoling YIN Key Laboratory of Guangdong for Utilization of Remote Sensing and Geographical Information System Guangdong Open Laboratory of Geospatial Information Technology and Application Guangzhou Institute of Geography Guangdong Academy of Sciences Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou) State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences College of Resources and Environment University of Chinese Academy of Sciences School of Traffic & Transportation Engineering Changsha University of Science and Technology

Mangroves are crucial to the ecological security of the Earth and human well-being. Their management, conservation, and restoration are of great importance and necessitate the support of spatio-temporal information and multidisciplinary knowledge such as biology and ecology. Traditional knowledge services such as plant atlas provide illustrated textual knowledge of mangroves. However, this kind of service is oriented to information retrieval and is incapable of effectively mining and utilizing fragmented knowledge from multi-source heterogeneous data, facing the problem of “massive data, rare knowledge”. Knowledge graphs are capable of extracting, organizing, and fusing the knowledge contained in massive data into semantic networks that can be understood and computed by computers. They provide a solution for the realization of intelligent knowledge services. Focusing on the urgent need for mangrove knowledge acquisition, formal representation, and intelligent services, this paper proposes a research prospect on mangrove knowledge graphs and knowledge services. We first analyze the similarities and differences between various domain-specific concepts of Tupu. On this basis, we define the mangrove knowledge graph as a large-scale knowledge base that integrates multi-disciplinary knowledge and spatio-temporal information with mangrove ecosystems as the core. Then, we propose a research framework for mangrove knowledge services that can realize the transformation from multi-modal data to intelligent knowledge services, including multiple research levels such as ubiquitous data sensing and aggregation, knowledge organization and graph construction, and intelligent mangrove knowledge services. Subsequently, the methods and workflow for constructing mangrove knowledge graphs are introduced. Finally, we discuss the challenges and possible future directions of mangrove knowledge services in the smart era, including the construction of a mangrove knowledge system that integra

关键词： Mangrove Tupu Knowledge graph Multi-modal Knowledge service