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Comparative Study of Low-Pass Filter and Phase-Locked Loop Type Speed Filters for Sensorless Control of AC Drives

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CES Transactions on Electrical Machines and Systems 2017年第2期1卷 207-215页

作者： Dong Wang kaiyuan lu Peter Omand Rasmussen Zhenyu Yang Department of Energy Technology Aalborg UniversityAalborgDK-9220Denmark IEEE

High quality speed information is one of the key issues in machine sensorless drives,which often requires proper filtering of the estimated speed.This paper comparatively studies typical low-pass filters(LPF)and phase-locked loop(PLL)type filters with respect to ramp speed reference tracking and steady-state performances,as well as the achievement of adaptive cutoff frequency control.An improved LPF-based filter structure with no ramping and steady-state errors caused by filter parameter quantization effects is proposed,which is suitable for applying LPF for sensorless drives of AC machines,especially when fixed-point digital signal processor is selected e.***.in mass production.Furthermore,the potential of adopting PLL for speed filtering is explored.It is demonstrated that PLL type filters can well maintain the advantages offered by the improved LPF.Moreover,it is found that the PLL type filters exhibit almost linear relationship between the cutoff frequency of the PLL filter and its proportional-integral(PI)gains,which can ease the realization of speed filters with adaptive cutoff frequency for improving the speed transient performance.The proposed filters are verified experimentally.The PLL type filter with adaptive cutoff frequency can provide satisfactory performances under various operating conditions and is therefore recommended.

关键词： Adaptive cutoff frequency low-pass filter machine sensorless drive phase-locked loop speed filter static error

Engineering neuroregenerative microenvironment via aligned hydrogel-assisted magnetic stimulation for complete spinal cord injury repair

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Engineered Regeneration

Engineered Regeneration 2024年第2期5卷 139-152页

作者： Chun-Yi Yang Zhe Meng Zhijun He Pengchao Ma Zhaohui Hou Kunkoo Kim Jingsong lu kaiyuan Yang Guihuai Wang Xiumei Wang State Key Laboratory of New Ceramics and Fine Processing Key Laboratory of Advanced Materials of Ministry of EducationSchool of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Department of Neurosurgery Beijing Tsinghua Changgung HospitalSchool of Clinical MedicineTsinghua UniversityBeijing102218China

Utilizing biomaterials in tissue engineering has shown considerable promise for tissue regeneration,particularly through delivering multimodel cell-regulatory signals,including the material-related signals and extrinsic stimuli.In this research,we developed a magnetic-responsive aligned nanofiber fibrin hydrogel(MAFG),integrating the structured alignment of nanofibers and the pliability of fibrin hydrogel with an external magnetic field.This design aimed to enhance the regenerative response in spinal cord injury treatment.A medium-strength magnetic field,aligned with the spinal cord,was applied to aid motor function recovery in rats with spinal cord injuries.The use of MAFG in this context not only intensified the effect of the magnetic field but also encouraged the activation and differentiation of native neural stem cells.Furthermore,this method effectively steered macrophage polarization towards a beneficial M2 phenotype,addressing immune dysregulation at the injury site.The parallel application of magnetic field stimulation through MAFG in a spinal cord injury model contributed to the concurrent promotion of neurogenesis,angiogenesis,and immunomodulation,resulting in marked improvement in motor function in rats.This investigation underscores the therapeutic potential of magnetic field stimulation and highlights how aligning this stimulation with the spinal cord can significantly enhance the regenerative milieu at the injury site.

关键词： Angiogenesis Neurogenesis Immunomodulation Magnetic-responsive hydrogel Magnetic stimulation

压缩机用内置式永磁同步电机无位置传感器控制

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电工技术学报 2013年第5期28卷 182-187页

作者：黄守道高剑肖磊陆凯元湖南大学电气与信息工程学院长沙410082 奥尔堡大学能源学院

分析了内置式永磁同步电机的数学模型,通过进行数学变形,提出了一种内置式永磁同步电机新的滑模位置观测器模型,模型只与q轴电感有关,而与d轴电感无关。同时采用双滤波器串联的方式来提取反电动势信息,可以实时测量在不同转速下的滤波... 详细信息

分析了内置式永磁同步电机的数学模型,通过进行数学变形,提出了一种内置式永磁同步电机新的滑模位置观测器模型,模型只与q轴电感有关,而与d轴电感无关。同时采用双滤波器串联的方式来提取反电动势信息,可以实时测量在不同转速下的滤波器相移用于角度补偿。在启动部分采用I-F启动策略并实现无冲击切换,以适应压缩机用内置式永磁同步电机在全速度范围内负载不断变化的工况。最后,对本文所提的控制算法进行实验验证,证明了所有控制策略的有效性。

关键词：压缩机内置式永磁同步电机滑模观测器无位置传感器控制

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以依法从严治军要求抓好部队管理工作

武警工程大学学报 2016年第2期32卷 63-67页

作者：鲁开源武警工程大学军事基础教育学院西安710086

针对以依法从严治军要求抓好部队管理工作这一课题，着重从“聚焦强军目标，着眼职能使命抓管理；强化法治思维，依据条令条例抓管理；坚持问题导向，紧盯薄弱环节抓管理；端正根本态度，切实改进作风抓管理”4个方面深入探讨了新形势... 详细信息

针对以依法从严治军要求抓好部队管理工作这一课题，着重从“聚焦强军目标，着眼职能使命抓管理；强化法治思维，依据条令条例抓管理；坚持问题导向，紧盯薄弱环节抓管理；端正根本态度，切实改进作风抓管理”4个方面深入探讨了新形势下部队如何科学施管、严格施管的具体措施。力求通过在这四个方面综合用力，推动部队高标准实现“两个确保”，从而在根本上为落实治军方针奠定坚实基础。

关键词：依法治军部队管理强军目标

乌东德水库库区大坪地滑坡形成机理与稳定性评价

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三峡大学学报（自然科学版） 2024年第2期46卷 55-62页

作者：张凯元邓华锋路永强滕明明王岚刘子俊三峡库区地质灾害教育部重点实验室(三峡大学) 湖北宜昌443002 三峡大学土木与建筑学院湖北宜昌443002 湖北省地质局水文地质工程地质大队湖北宜昌443002 梁山县水务局山东济宁272699

鲹鱼河作为金沙江距离乌东德水电站最近的支流水系,大坪地滑坡是其右岸发育7个滑坡中规模较大的一个,其蓄水之后的稳定性及其后期发展演化趋势对乌东德水电站的安全运行具有重要影响.在野外地质调查研究的基础上,通过岩芯观察和监测资... 详细信息

鲹鱼河作为金沙江距离乌东德水电站最近的支流水系,大坪地滑坡是其右岸发育7个滑坡中规模较大的一个,其蓄水之后的稳定性及其后期发展演化趋势对乌东德水电站的安全运行具有重要影响.在野外地质调查研究的基础上,通过岩芯观察和监测资料分析,对大坪地滑坡的形成机理和与稳定性进行了研究评价,结果表明:滑坡位于喇叭口向斜的南翼近核部,为斜顺向坡~顺向坡结构,该向斜的北翼对滑坡的运动起到了控制作用,限制了其向北延伸,并对大坪地滑坡形成侧向挤压.大坪地滑坡类型为一岩质滑坡,目前表现为蠕动变形,受库水影响滑坡前缘累计变形近2 m,特别是在库水位下降阶段,滑坡变形强烈,表明大坪地滑坡具有动水压型岩质滑坡属性.稳定性计算结果表明,大坪地滑坡在库水位下降工况下,处于极限平衡状态.

关键词：乌东德水电站大坪地滑坡岩土体结构

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洗衣机装配缝隙与阶差测量系统设计

测试技术学报 2024年第4期38卷 378-386页

作者：朱开源陆永华冯强周利华南京航空航天大学机电学院江苏南京210016 国营锦江机械厂四川成都610043

提出一种基于线结构光的缝隙和阶差尺寸测量方法,通过搭建洗衣机表面质量视觉检测平台,采集洗衣机缝隙图像,设计了一种洗衣机缝隙检测算法,在阈值分割、缝隙定位后获取缝隙ROI图像,采用最小二乘法拟合缝隙边缘,利用线结构光传感器进行标... 详细信息

提出一种基于线结构光的缝隙和阶差尺寸测量方法,通过搭建洗衣机表面质量视觉检测平台,采集洗衣机缝隙图像,设计了一种洗衣机缝隙检测算法,在阈值分割、缝隙定位后获取缝隙ROI图像,采用最小二乘法拟合缝隙边缘,利用线结构光传感器进行标定,根据标定结果计算缝隙尺寸;设计了一种洗衣机阶差检测算法,通过阶差位置获取光条图像,在阈值分割、中心线提取后,寻找阶差两侧的特征点,将二维坐标转换为三维坐标计算阶差。试验结果表明:系统缝隙检测误差0.124 mm,阶差检测误差0.170 mm,满足洗衣机缝隙与阶差测量的要求。

关键词：机器视觉线结构光洗衣机装配缝隙缝隙与阶差测量

Theoretical study of broadband near-field optical spectrum of twisted bilayer graphene

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Frontiers of physics 2022年第4期17卷 67-74页

作者： lu Wen Yijun Liu Guoyu luo Xinyu Lv kaiyuan Wang Wang Zhu Lei Wang Zhiqiang Li College of Physics Sichuan UniversityChengdu 610064China National Laboratory of Solid-State Microstructures School of PhysicsNanjing UniversityNanjing 210093China

We theoretically study the broadband near-field optical spectrum of twisted bilayer graphene(TBG)at various twist angles near the magic angle using two different models.The spectrum at low Fermi energy is characterized by a series of peaks that are almost at the same energies as the peaks in the far-field optical conductivity of TBG.When the Fermi energy is near a van Hove singularity,an additional strong peak appears at finite energy in the near-field spectrum,which has no counterpart in the optical conductivity.Based on a detailed calculation of the plasmon dispersion,we show that these spectroscopic features are associated with interband and intraband plasmons,which can provide critical information about the local band structure and plasmonic excitations in TBG.The near-field peaks evolve systematically with the twist angle,so they can serve as fingerprints for identifying the spatial dependent twist angle in TBG samples.Our findings pave the way for future experimental studies of the novel optical properties of TBG in the nanoscale.

关键词： twisted bilayer graphene SNOM broadband near-field optical spectrum,optical conductivity magic angle

A FLASH pipeline for arrayed CRISPR library construction and the gene function discovery of rice receptor-like kinases

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Molecular Plant 2022年第2期15卷 243-257页

作者： kaiyuan Chen Runnan Ke Manman Du Yuqing Yi Yache Chen Xiaochun Wang lu Yao Hao Liu Xin Hou Lizhong Xiong Yinong Yang Kabin Xie National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research(Wuhan) Hubei Hongshan LaboratoryHuazhong Agricultural UniversityNo.1 Shizishan StreetHongshan DistrictWuhan 430070China Hubei Key Laboratory of Plant Pathology Huazhong Agricultural UniversityWuhan 430070China State Key Laboratory of Hybrid Rice College of Life SciencesWuhan UniversityWuhan 430072China Department of Plant Pathology and Environmental Microbiology The Huck Institutes of Life SciencesThe Pennsylvania State UniversityUniversity ParkPA 16802USA Shenzhen Institute of Nutrition and Health Huazhong Agricultural UniversityWuhan 430070China

Clustered regularly interspaced short palindromic repeats(CRISPR)-CRISPR-associated protein 9(Cas9)-mediated gene editing is revolutionizing plant research and crop breeding.Here,we present an effective and streamlined pipeline for arrayed CRISPR library construction and demonstrate it is suitable for small-to large-scale genome editing in plants.This pipeline introduces artificial PCR fragment-length markers for distinguishing guide RNAs(gRNAs)(FLASH),and a group of 12 constructs harboring different FLASH tags are co-transformed into plants each time.The identities of gRNAs in Agrobacterium mixtures and trans-genic plants can therefore be read out by detecting the FLASH tags,a process that requires only conven-tional PCR and gel electrophoresis rather than sequencing.We generated an arrayed CRISPR library target-ing all 1,072 members of the receptor-like kinase(RLK)family in rice.One-shot transformation generated a mutant population that covers gRNAs targeting 955 RLKs,and 74.3%(710/955)of the target genes had three or more independent T0 lines.Our results indicate that the FLASH tags act as bona fide surrogates for the gRNAs and are tightly(92.1%)associated with frameshift mutations in the target genes.In addition,the FLASH pipeline allows for rapid identification of unintended editing events without corresponding T-DNA integrations and generates high-order mutants of closely related RLK genes.Furthermore,we showed that the RLK mutant library enables rapid discovery of defense-related RLK genes.This study introduces an effective pipeline for arrayed CRISPR library construction and provides genome-wide rice RLK mutant resources for functional genomics.

关键词： CRISPR library gene editing high throughput receptor-like kinaserice

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唐东都洛阳圣善寺考

华夏考古 2024年第2期 111-116,138页

作者：卢亚辉中国社会科学院考古研究所北京市100710

依隋唐洛阳城里坊最新考古勘探与发掘成果,结合出土墓葬(志)材料与传统文献,本文推定唐代圣善寺作为神龙政变之后营建的政治景观,只存在于洛阳一处。圣善寺是舍宅为寺或改原有寺庙而成,其所在区域的建筑规模与体量,不能满足功能需求,故... 详细信息

依隋唐洛阳城里坊最新考古勘探与发掘成果,结合出土墓葬(志)材料与传统文献,本文推定唐代圣善寺作为神龙政变之后营建的政治景观,只存在于洛阳一处。圣善寺是舍宅为寺或改原有寺庙而成,其所在区域的建筑规模与体量,不能满足功能需求,故唐中宗建报慈阁,安置佛像,后又基于隋唐洛阳城原有的里坊规划,以50余步为准扩建僧房。营建后的圣善寺成为洛阳东南部一处信仰中心与公共空间,圣善寺的营建导致章善坊内用地性质的改变,最直接的结果是玄宗开元、天宝时期坊内居住者墓志数量的锐减。

关键词：唐洛阳城圣善寺慧范政治景观