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Single neuron network PI control of high reliability linear induction motor for Maglev

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第3期8卷 408-411页

作者： fang you-tong FAN Cheng-zhi College of Electrical Engineering Zhejiang University Hangzhou 310027 China

The paper deals with a new model of linear induction motor (LIM) to improve the reliability of the system. Based on the normal equation circuit of LIM considering the dynamic end effect, an equivalent circuit model with compensation of large end effect is constructed when the end effect force at synchronism is of braking character. The equivalent circuit model is used for secondary-flux oriented control of LIM. Single neuron network PI unit for LIM servo-drive is also discussed. The effectiveness of mathematical model for drive control is verified by simulations.

关键词： Linear induction motor (LIM) Field-oriented control End effect

Inspection-replacement policy of system under predictive maintenance

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第3期8卷 495-500页

作者： LIU Bao-you fang you-tong WEI Jin-xiang WANG Yong-liang Department of Mathematics and Physics Shijiazhuang Railway Institute Shijiazhuang 050043 China College of Electrical Engineering Zhejiang University Hangzhou 310027 China Extrahigh Tension Transmittal and Transformation Company Branch Hebei Electric Power Company Shijiazhuang 050051 China

In general, every system is in one of the three states： normal, abnormal, or failure state. When the system is diagnosed as abnormal state, it needs predictive maintenance, lfthe system fails, an identical new one will replace it. The predictive maintenance cannot make the system ＂as good as new＂. Under these assumptions, the reliability index and the inspection-replacement policy of a system were studied. The explicit expression of the reliability index and the average income rate （i.e., the long-run average income per unit time） are derived by using probability analysis and vector Markov process method. The criterion of feasibility for the optimal inspection-replacement policy under the maximum average income rate is obtained. The numerical example shows the optimal inspection-replacement policy can raise the average income rate when the optimal inspection-replacement policy is feasible.

关键词： lnspection-replacement policy. Inspection and diagnosis. Monotone stochastic process. Reliability index Vector Markov process method

Role of alloying and heat treatment on microstructure and mechanical properties of cast Al-Li alloys:A review

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China Foundry 2024年第5期21卷 445-460页

作者： Guo-hua Wu you-jie Guo fang-zhou Qi Shen Zhang Yi-xiao Wang Xin tong Liang Zhang School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Due to the prominent advantages of low density,high elastic modulus,high specific strength and specific stiffness,cast Al-Li alloys are suitable metallic materials for manufacturing complex large-sized components and are ideal structural materials for aerospace,defense and military *** the basis of the microstructural characteristics of cast Al-Li alloys,exploring the role of alloying and micro-alloying can stabilize their dominant position and further expand their application *** this review,the development progress of cast Al-Li alloys was summarized *** to the latest research highlights,the influence of alloying and heat treatment on the microstructure and mechanical properties was systematically *** potential methods to improve the alloy performance were *** response to the practical engineering requirements of cast Al-Li alloys,the scientific challenges and future research directions were discussed and prospected.

关键词： cast Al-Li alloy alloying microstructure mechanical properties heat treatment

Treatment of multisystem inflammatory syndrome in children

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World Journal of Pediatrics 2024年第4期20卷 325-339页

作者： tong tong Yi-Hua Jin Min Wang fang-Qi Gong Department of Cardiology Children's HospitalZhejiang University School of MedicineNational Clinical Research Center for Child HealthNo.3333 Binsheng RoadHangzhou 310052China

Background Multisystem inflammatory syndrome in children(MIS-C),a relatively uncommon but severe pediatric complication,is associated with coronavirus disease 2019(COVID-19).A variety of treatment approaches,including intravenous immunoglobulins(IVIGs),glucocorticoids(GCs)and biologic agents,such as anakinra and infliximab,have been described for the management of COVID-19-related *** therapy is also ***,a well-developed treatment system has not been established,and many issues remain *** recently published articles related to the treatment of MIS-C have been ***,in this review,we identified relevant articles published recently and summarized the treatment of MIS-C more comprehensively and *** sources We reviewed the literature on the treatment of MIS-C through 20 September *** PubMed/Medline,Web of Science,EMBASE,and Cochrane Library databases were searched with the combination of the terms"multisystem inflammatory syndrome","MIS-C","PIMS-TS","therapy","treatment","drug","IVIG","GCs","intravenous immunoglobulin","corticosteroids","biological agent",and"aspirin".Results The severity of MIS-C varies,and different treatment schemes should be used according to the specific *** research and data collection are vital to better understand the pathophysiology and optimal management of *** MIS-Cis a disease involving multiple systems and has great *** the accumulation of additional experience,we have garnered fresh insights into its treatment ***,there remains a critical need for greater standardization in treatment protocols,alongside the pressing necessity for more robust and meticulously conducted studies to deepen our understanding of these protocols.

关键词： Coronavirus disease 2019-Corticosteroids Intravenous immunoglobulin Multisystem inflammatory syndrome in children-Treatment

Dynamic Location Method for Shallow Ocean Bottom Nodes Using the Levenberg-Marquart Algorithm

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Journal of Ocean University of China 2024年第4期23卷 953-960页

作者： tong Siyou LI Junjie XU Xiugang fang Yunfen WANG Zhongcheng Key Laboratory of Submarine Geosciences and Prospecting Techniques MOEOcean University of ChinaQingdao 266100China Laboratory for Marine Mineral Resources Qingdao Marine Science and Technology CenterQingdao 266237China R&D Center of BGP CNPCZhuozhou 072751China Insitute of Shengli Oilfield SINOPECDongying 257022China

Ocean bottom node(OBN)data acquisition is the main development direction of marine seismic exploration;it is widely promoted,especially in shallow sea ***,the OBN receivers may move several times because they are easily affected by tides,currents,and other factors in the shallow sea environment during long-term *** uncorrected,then the imaging quality of subsequent processing will be *** conventional secondary positioning does not consider the case of multiple movements of the receivers,and the accuracy of secondary positioning is *** first arrival wave of OBN seismic data in shallow ocean mainly comprises refracted *** this study,a nonlinear model is established in accordance with the propagation mechanism of a refracted wave and its relationship with the time interval curve to realize the accurate location of multiple receiver *** addition,the Levenberg-Marquart algorithm is used to reduce the influence of the first arrival pickup error and to automatically detect the receiver movements,identifying the accurate dynamic relocation of the *** simulation and field data show that the proposed method can realize the dynamic location of multiple receiver movements,thereby improving the accuracy of seismic imaging and achieving high practical value.

关键词： OBN dynamic location method Levenberg-Marquart algorithm seismic exploration of shallow sea

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低开关频率选择谐波消除调制的母线波动补偿

浙江大学学报（工学版） 2019年第2期53卷 388-398页

作者：赵硕丰黄晓艳方攸同浙江大学电气工程学院浙江杭州310027

提出基于选择谐波消除脉宽调制(SHEPWM)的补偿策略,用于抑制由直流母线电压波动引起的列车牵引电机电流与转矩波动.根据每一基波周期内的调制脉冲数确定同步处理区间,使用重复预测器对下一处理区间内的直流母线电压波形进行预测.根据预... 详细信息

提出基于选择谐波消除脉宽调制(SHEPWM)的补偿策略,用于抑制由直流母线电压波动引起的列车牵引电机电流与转矩波动.根据每一基波周期内的调制脉冲数确定同步处理区间,使用重复预测器对下一处理区间内的直流母线电压波形进行预测.根据预测的母线电压波形与开关时刻估计下一处理区间内的磁链误差,并相应地调整开关时刻以消除磁链误差.在18 kW永磁体内置式永磁同步电动机(IPMSM)上分别对采用完整的补偿策略、采用近似的处理区间内平均母线电压补偿策略与不采用任何补偿策略的情况进行实验.结果表明提出的补偿策略能显著降低由直流母线电压波动所引起的低次电流谐波和电机转矩波动,且相比近似的处理区间内平均母线电压补偿策略具有更好的电流与转矩波动抑制效果.

关键词：列车牵引直流母线电压波动选择谐波消除脉宽调制(SHEPWM) 重复预测器永磁同步电机(PMSM)

High-efficiency preparation of multifunctional conjugated electrospun graphene doped PVDF/CF yarns for energy harvesting and human movement monitoring in TENG textile

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Nano Research 2024年第5期17卷 4478-4488页

作者： Ting Yang Chengwei Wan Xiaoyu Zhang tong Liu Li Niu Jian fang Yuqing Liu College of Textile and Clothing Engineering Soochow UniversitySuzhou 215123China

Portable power is an effective solution to realize self-powered sensors for wearable devices,promoting future sustainable ***-based triboelectric nanogenerators(M-TENGs)have emerged as a promising technology for harvesting biomechanical energy from human motion owing to their advantages,such as simple structure,lightweight design,and efficient energy ***,the poor durability,low adaptability,and un-washability of two-dimensional membrane materials have largely hindered their application in wearable *** this study,we propose a sheath-core polyvinylidene fluoride(PVDF)/graphene(G)-carbon fiber(CF)yarn fabricated via conjugate electrospinning,comprising a commercial CF core and an electrospun graphene-doped PVDF sheath,which improves the fatigue resistance of electrospun nanofiber films under prolonged friction and keeps a high degree of *** resulting electronic textile,woven with the large-scale electrospun PVDF/G-CF yarn,demonstrates a remarkable power density of 25.5 mW·m^(-2).The tight distribution of PVDF/G nanofibers on the textile surface ensures excellent softness,washability,and ***,the electrospun PVDF/G-CF textile exhibits significant potential in pressure sensing,self-powered operation,and motion detection,making it highly suitable for wearable electronics applications.

关键词： yarn-based triboelectric nanogenerator(TENG) graphene polyvinylidene fluoride(PVDF) conjugated-electrospinning multifunctional

永磁同步电机有限控集模型预测电流控制预测误差分析

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电机与控制学报 2019年第4期23卷 1-7页

作者：李键牛峰黄晓艳方攸同浙江大学电气工程学院杭州310027 河北工业大学省部共建电工装备可靠性与智能化国家重点实验室天津300130

在采用有限控集模型预测电流控制策略的永磁同步电机驱动系统中,预测模型使用的电机参数尤其是定子电感可能与实际值并不匹配,会造成模型预测控制算法存在预测上的误差,进而影响系统稳态控制性能。针对该问题,首先定义了预测误差作为评... 详细信息

在采用有限控集模型预测电流控制策略的永磁同步电机驱动系统中,预测模型使用的电机参数尤其是定子电感可能与实际值并不匹配,会造成模型预测控制算法存在预测上的误差,进而影响系统稳态控制性能。针对该问题,首先定义了预测误差作为评价指标,然后推导出电流预测误差的数学模型,理论分析表明预测模型使用的d、q轴电感值正向偏差和负向偏差对于d、q轴电流预测误差会产生不一样的影响,且负向偏差影响更大。实验结果验证了上述关于电流预测误差的理论分析,同时对相应的电流稳态跟踪误差进行了实验分析,显示出预测误差对于稳态跟踪性能的影响。得到的预测误差数学模型和分析结论能够为模型预测算法预测误差的降低和控制性能的提升提供理论指导。

关键词：有限控集模型预测电流控制永磁同步电机参数误差预测误差

Network Pharmacology and Molecular Docking Analysis of the Mechanisms of Combined Radix Bupleuri(Chai-Hu) and Radix Paeoniae Alba(Bai-Shao) Treatment in the Prevention and Treatment of Alzheimer's Disease

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World Journal of Traditional Chinese Medicine 2024年第2期10卷 254-262页

作者： Zhao-Han Huang Yuan fang Qi Yu tong Wang College of Traditional Chinese Medicine Beijing University of Chinese MedicineBeijingChina Shanghai Center for Women and Children's Health ShanghaiChina

Objective: Radix Bupleuri and Radix Paeoniae Alba are referred to as Chai-Hu and Bai-Shao, respectively, in Chinese. We used molecular docking and network pharmacological approaches to explore the active components of this Chinese herb combination which is commonly used for treating Alzheimer's disease(AD), the Chai-Hu and Bai-Shao pair(CBP). Materials and Methods: The active compounds and action targets of Chai-Hu and Bai-Shao were identified in the Traditional Chinese Medicine Systems Pharmacology database, and the Therapeutic Target Database, Drug Bank, Gen Cards, Dis Ge NET, and Online Mendelian Inheritance in Man databases were used to identify therapeutic targets in patients with AD. To identify a common target of CBP in the treatment of AD, we used the Metascape tool to perform Gene Ontology function enrichment and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses. In addition, CBP-AD protein–protein interaction(PPI) and herb-component-target networks were created using Cytoscape 3.8.2. Molecular docking was verified using Auto Dock tools. Results: We identified 20 active compounds of CBP, 202 active targets, 1,323 disease targets, and 117 active compound disease intersection targets;the PPI network showed that the top eight key targets were AKT1, interleukin(IL) 6, JUN, MAPK1, tumor necrosis factor, TP53, vascular endothelial growth factor, and epidermal growth factor. These act mainly on the fluid shear stress, atherosclerosis, IL-17, hypoxia-inducible factor-1, and nonalcoholic fatty liver disease pathways, among others, which control immune inflammation, cell proliferation, and apoptosis. Based on molecular docking results, the active components of CBP bind well to its key targets. Conclusion: Our results indicated that CBP was effective for treating AD by reducing the expression of inflammatory factors, promoting cell proliferation and differentiation, and preventing nerve cell death and anti-neuronal cell apoptosis.

关键词： Alzheimer's disease Bai-Shao Chai-Hu molecular docking network pharmacology