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高等数学教学中微课的运用探讨

科教文汇 2019年第26期 49-50页

作者：李宇健盐城幼儿师范高等专科学校

微课教学模式在高等数学教学中的合理应用,不仅可以调动高等院校大学生数学学习的积极性,而且可以为高等数学教学质量的提升提供良好的依据。因此,本文以高等数学为研究背景,阐述了高等数学教学中微课的内涵,分析了高等数学教学中微课... 详细信息

微课教学模式在高等数学教学中的合理应用,不仅可以调动高等院校大学生数学学习的积极性,而且可以为高等数学教学质量的提升提供良好的依据。因此,本文以高等数学为研究背景,阐述了高等数学教学中微课的内涵,分析了高等数学教学中微课的设计方法,并对高等数学教学中微课的运用进行了进一步探究。

关键词：高等数学微课智能移动设备

Boosting the performance of liNi_(0.90)Co_(0.06)Mn_(0.04)O_(2) electrode by uniform li_(3)PO_(4) coating via atomic layer deposition

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Chinese Chemical Letters 2024年第5期35卷 499-503页

作者： Mingjiao Lu Zhixing Wang Gui Luo Huajun Guo Xinhai li Guochun Yan Qihou li Xianglin li Ding Wang Jiexi Wang School of Metallurgy and Environment Central South UniversityChangsha 410083China BASF ShanShan Battery Materials Co. Ltd.Changsha 410006China Engineering Research Center of the Ministry of Education for Advanced Battery Materials Central South UniversityChangsha 410083China Hunan Provincial Key Laboratory of Nonferrous Value-Added Metallurgy Central South UniversityChangsha 410083China School of Physics and Chemistry Hunan First Normal UniversityChangsha 410205China National and Local Joint Engineering Laboratory for lithium-ion Batteries and Materials Preparation Technology Key Laboratory of Advanced Battery Materials of Yunnan ProvinceFaculty of Metallurgical and Energy EngineeringKunming University of Science and TechnologyKunming 650093China

Ultra-high nickel material is considered to be a promising cathode ***,with the increase of nickel content,the interfacial side reactions between the cathode and electrolyte become increasingly ***,an atomically controllable ionic conductor li_(3)PO_(4)(LPO)coating is deposited on the liNi_(0.90)Co_(0.06)Mn_(0.04)O_(2)(NCM9064)based electrode by the atomic layer deposition *** results shows that the LPO coating is uniformly and densely covered on the surface of secondary particles of NCM9064,helping to prevent the direct contact between the electrolyte and cathode during the chargingdischarging *** addition,the coating layer is electrochemically *** a result,the interfacial side reactions during the long cycle are effectively suppressed,and the solid electrolyte interphase layer at the interface is *** electrode with 20 layers of LPO deposition(ALD-LPO-20)exhibits an excellent capacity retention of 81%after 200 cycles in 2.8-4.3 V at 25℃,which is 18%higher than the unmodified material(ALD-LPO-0).Besides,the moderate LPO coating improves the rate capability and high temperature cycling performance of *** study provides a method for the modification of ultra-high nickel cathode materials and corresponding electrodes.

关键词： Ultra-high nickel material liNi_(0.90)Co_(0.06)Mn_(0.04)O_(2) Atomic layer deposition li_(3)PO_(4) Ionic conductor

用户统一管理在郑州轨道信息化建设中的研究与实现

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计算机应用与软件 2019年第6期36卷 101-103,208页

作者：夏景辉秦义展李昱见郑州地铁集团有限公司河南郑州450046

提出一种用于地铁企业的用户统一管理方案,实现了企业信息管理过程中的用户身份库管理、用户授权管理和用户认证管理。通过对地铁企业用户的现状分析、关键需求整理和方案实施,给出用户统一管理的效果分析。实践证明,该方案有效提高了... 详细信息

提出一种用于地铁企业的用户统一管理方案,实现了企业信息管理过程中的用户身份库管理、用户授权管理和用户认证管理。通过对地铁企业用户的现状分析、关键需求整理和方案实施,给出用户统一管理的效果分析。实践证明,该方案有效提高了用户访问快捷性、用户管理科学性、用户授权安全性、用户审计准确性、用户同步及时性,还可以为地铁企业组织架构的频繁调整带来技术保障,同时也为用户信息统计及分析奠定了基础。

关键词：用户统一管理用户认证管理用户授权管理

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基于电池功率的永磁同步电机预测电流控制

国外电子测量技术 2023年第1期42卷 126-131页

作者：张利国厉风李宇剑李航张增财东北石油大学秦皇岛校区秦皇岛066000 东北石油大学大庆163000

纯电动汽车动力电池的荷电状态下降到一定程度时,会出现电池实际输出功率无法满足控制需求的情况。考虑电池功率对电机控制的影响,建立基于电池输出功率的永磁同步电机预测电流控制策略。使用无差拍预测控制预测电流值,进而计算电机期... 详细信息

纯电动汽车动力电池的荷电状态下降到一定程度时,会出现电池实际输出功率无法满足控制需求的情况。考虑电池功率对电机控制的影响,建立基于电池输出功率的永磁同步电机预测电流控制策略。使用无差拍预测控制预测电流值,进而计算电机期望功率。当电机期望功率超出电池功率时,通过降低目标转速和对控制电流限幅的方式降低期望功率值。通过仿真及实验验证,提出的控制策略能够在电池输出功率下降的情况下,降低电机期望功率,使电机能继续正常运转。并且与传统控制策略相比,电机动态响应速度更快,响应时间缩短50%以上,功率波动更小,动态性能明显提升。结果表明,基于电池输出功率的永磁同步电机电流预测控制策略是有效的。

关键词：动力电池永磁同步电机无差拍预测控制功率

Layered niobium carbide enabling excellent kinetics and cycling stability of li-Mg-B-H hydrogen storage material Layered niobium carbide enabling excellent kinetics

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Rare Metals 2024年第3期43卷 1153-1166页

作者： li-Wen Lu Hui Luo Guang-Xu li Yun li Xin-Hua Wang Cun-Ke Huang Zhi-QiangLan Wen-Zheng Zhou Jin Guo Mohammad Ismail Hai-Zhen liu Guangxi Novel Battery Materials Research Center of Engineering Technology Guangxi Colleges and Universities Key Laboratory of Blue Energy and Systems IntegrationSchool of Physical Science and TechnologyGuangxi UniversityNanning530004China State Key Laboratory of Featured Metal Materials and life-Cycle Safety for Composite Structures Nanning530004China School of Mechanical and Electrical Engineering Quzhou College of TechnologyQuzhou324000China Department of Materials Science and Engineering Zhejiang UniversityHangzhou310027China Faculty of Ocean Engineering Technology and Informatics Universiti Malaysia Terengganu21030Kuala NerusTerengganuMalaysia Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin300071China

The li-Mg-B-H composite(2liBH_(4)+MgH_(2))has a high capacity of 11.4 wt%as a hydrogen storage ***,the slow kinetics and poor cycling stability severely restrict its practical *** this work,a layered Nb_(2)C MXene was first synthesized and then introduced to tailor the kinetics and cycling stability of the li-Mg-B-H *** milled 2liH+MgB_(2)composites were initially hydrogenated to obtain the 2liBH_(4)+MgH_(2)*** 2liBH_(4)+MgH_(2)+5wt%Nb_(2)C can release 9.0 wt%H_(2)in 30 min at 400℃,while it is only 2.7 wt%for the undoped 2liBH_(4)+MgH_(2).The dehydrogenation activation energies of MgH_(2)and liBH_(4)are 123 and 154 kJ·mol^(-1)respectively for the 5 wt%Nb_(2)C-doped composite,lower than the undoped composite(164 and 165 kJ·mol^(-1)).The 2liBH_(4)+MgH_(2)+5 wt%Nb_(2)C possesses excellent cycling stability,with the reversible capacity only slightly reduced from 9.4 wt%for the 1st cycle to 9.3 wt%for the 20th ***_(2)C keeps stable in the composite and acts as an efficient catalyst for the li-Mg-B-H *** is believed that both the layered structure and the active Nb element contribu te to the enhanced hydrogen storage performances of the li-Mg-B-H *** work confirms that the Nb_(2)C MXene with layered stru cture has a significant enhancing impact on the li-Mg-B-H hydrogen storage materials,which is different from the bulk NbC.

关键词： Hydrogen storage lithium borohydride Magnesium hydride Nb_(2)C MXene

Hard-carbon hybrid li-ion/metal anode enabled by preferred mesoporous uniform lithium growth mechanism

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Journal of Energy Chemistry 2024年第1期88卷 252-259,I0006页

作者： Fang Yan Yan liu Yuan li Yan Wang Zicen Deng Meng li Zhenwei Zhu Aohan Zhou Ting li Jingyi Qiu Gaoping Cao Shaobo Huang Biyan Wang Hao Zhang School of Chemistry and Biological Engineering University of Science and TechnologyBeijing 100083China Research Institute of Chemical Defense Beijing 100191China College of Physics and Engineering Henan University of Science and TechnologyLuoyang 471023HenanChina National Base for International Science&Technology Cooperation School of ChemistryXiangtan UniversityXiangtan 411105HunanChina Materials and Manufacturing Department Beijing University of TechnologyBeijing 100124China

To achieve high energy density in lithium batteries,the construction of lithium-ion/metal hybrid anodes is a promising *** particular,because of the anisotropy of graphite,hybrid anode formed by graphite/li metal has low transport kinetics and is easy to causes the growth of lithium dendrites and accumulation of dead li,which seriously affects the cycle life of batteries and even causes safety ***,by comparing graphite with two types of hard carbon,it was found that hybrid anode formed by hard carbon and lithium metal,possessing more disordered mesoporous structure and lithophilic groups,presents better *** indicate that the mesoporous structure provides abundant active site and storage space for dead *** the synergistic effect of this structure and lithophilic functional groups(–COOH),the reversibility of hard carbon/lithium metal hybrid anode is maintained,promoting uniform deposition of lithium metal and alleviating formation of lithium *** hybrid anode maintains a 99.5%Coulombic efficiency(CE)after 260 cycles at a specific capacity of 500 m Ah/*** work provides new insights into the hybrid anodes formed by carbon-based materials and lithium metal with high specific energy and fast charging ability.

关键词： Hard carbon/li metal hybrid anode Mesoporous structure Surface oxygen functional group Fast charging lithium batteries

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基于组合凸线性感知器的文本分类模型

北京工业大学学报 2017年第11期43卷 1681-1689页

作者：李玉鑑王曼丽刘兆英北京工业大学信息学部北京100124

针对文本分类问题,从分片线性学习的角度出发,提出了一种文本分类的组合凸线性感知器模型.首先,对文本样本集进行预处理,包括特征选择、特征项赋权等;然后,分别利用生长支持组合凸线性感知器算法(growing support multiconlitron algori... 详细信息

针对文本分类问题,从分片线性学习的角度出发,提出了一种文本分类的组合凸线性感知器模型.首先,对文本样本集进行预处理,包括特征选择、特征项赋权等;然后,分别利用生长支持组合凸线性感知器算法(growing support multiconlitron algorithm,GSMA)和支持组合凸线性感知器算法(support multiconlitron algorithm,SMA)构造组合凸线性感知器,对样本集进行分类.该模型基于支持向量机的最大间隔思想,通过集成线性分类器,实现了对2类数据的划分,具有计算简单、适应能力强的优点.在标准文本数据集上的实验结果表明:该模型所构造的分类器具有良好的文本分类性能,与其他典型文本分类方法的对比也说明了该方法的有效性.

关键词：分片线性分类器组合凸线性感知器文本分类

Research on the utilization of network resources

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Research on the utilization of network resources

2008奥林匹克科学大会

作者： Lei,Qiang~1 You,Kun~2 & li,yujian~3 1 Xian Institute Of Physical Education,China 2 Xi'anShiyou University,China 3 Xi'an Academy Of Fine Arts, China

Introduction The sports community places large demands on the rich network of information ***,it also exists for the purpose of usefully finding and utilizing the sport networks *** purpose of this article is to analyze the reasons causing the lower utilization of sports network resources in China and provide beneficial techniques to utilize these network *** investigation will provide a beneficial reference for developing and constructing the sport network resources within China.

关键词： Research on the utilization of network resources

来源： cnki会议评论

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半自动眉毛识别方法

计算机工程与应用 2011年第31期47卷 201-205页

作者：李玉鑑张夏欢张晨光北京工业大学计算机学院北京100124 海南大学信息科学技术学院海口571737

提出了基于哈希图半监督学习和支持向量机的半自动眉毛识别方法。针对图半监督学习构图时间复杂度过高的缺点,提出了基于哈希图半监督学习的纯眉毛图像半自动提取方法。在纯眉毛图像的基础上通过傅里叶变换和Gabor变换及主成分分析提取... 详细信息

提出了基于哈希图半监督学习和支持向量机的半自动眉毛识别方法。针对图半监督学习构图时间复杂度过高的缺点,提出了基于哈希图半监督学习的纯眉毛图像半自动提取方法。在纯眉毛图像的基础上通过傅里叶变换和Gabor变换及主成分分析提取纯眉毛图像的特征向量,用于支持向量机的训练和识别。在北工大眉毛数据库上,通过眉毛识别实验,分析了图半监督学习和哈希图半监督学习对提取纯眉毛图像速度的影响,并且总结了它们与特征向量和核函数的选择对识别率的影响。

关键词：眉毛识别图半监督学习支持向量机傅里叶变换主成分分析